Providing a small-sized acceleration sensor including a vibrator formed of a piezoelectric single crystal, and a weight section connected to the vibrator and supported at a position different from the position of the center of gravity of an assembly of the vibrator and weight section. Two divided electrodes used for detecting an electrical signal are formed on the vibrator and connected to two wiring patterns of the weight section which also functions as a signal detecting substrate, with an anisotropic conductive adhesive. When an acceleration in one direction is applied, an angular moment exerted in the weight section is detected as sliding vibration by the vibrator, and an electrical signal corresponding to the acceleration is output from the electrodes through the wiring patterns.

The present invention relates to an acceleration sensor for detecting an acceleration, and more particularly to an acceleration sensor for detecting an acceleration by sliding vibration, which is exerted when an acceleration is applied, and to an acceleration sensor device constructed by storing this acceleration sensor in a package.
An acceleration sensor is installed in equipment to monitor an abnormal condition of the equipment by detecting an acceleration and vibration of the equipment. For example, the acceleration sensor is used to prevent errors in reading and writing data resulting from vibration and shock in a hard disk drive, to prevent hand shaking in a video camera, to actuate an air bag in a vehicle, etc.
With a reduction in size and an increase in the performance of equipment in which an acceleration sensor is to be installed, there has been a demand for the development of a small-sized, high-performance acceleration sensor capable of being mounted on a surface of the equipment. As such a small-sized acceleration sensor, an acceleration sensor using a piezoelectric element has been conventionally put into practice. Disclosed examples of such an acceleration sensor include an acceleration sensor which detects an acceleration by using a deflection of a piezoelectric single crystal (Japanese Patent Application Laid-Open Nos. 10-206456/1998 and 11-211748/1999) and an acceleration sensor which detects an acceleration by using a deflection of piezoelectric ceramic (Japanese Patent Application Laid-Open No. 6-273439/1994).
Acceleration sensors using the deflection of a piezoelectric single crystal or the deflection of piezoelectric ceramic as mentioned above can improve the detection sensitivity by increasing the deflection to increase the stress. Thus, in order to improve the detection sensitivity for high performance, the mass needs to be increased to produce a larger deflection, causing a problem that the acceleration sensor becomes heavier and larger in size. On the other hand, when the piezoelectric element is made thicker, it does not easily deflect and causes a problem that the detection sensitivity is lowered. Then, in order to improve the detection sensitivity, there have been proposals to make the piezoelectric element thinner, to stick two pieces of extremely thin piezoelectric elements together, etc. However, such proposals are associated with problems that the fabrication process is complicated and the cost is increased.
Therefore, the applicant of the present invention proposed an acceleration sensor capable of detecting an acceleration with good sensitivity by a small-sized structure (Japanese Patent Application Laid-Open No. 2000-97707). This acceleration sensor comprises a vibrator and a weight section which is connected and supported at a position different from the position of the center of gravity of an assembly of the vibrator and weight section, and obtains the magnitude of an applied acceleration by detecting the amount of characteristic (sliding vibration) of the vibrator corresponding to an angular moment exerted in the weight section when the acceleration is applied. The present inventors are pursuing the development and improvement of such an acceleration sensor that has a small-sized structure and a high detection sensitivity without increasing the size of the vibrator to achieve high performance because it detects sliding vibration instead of deflective vibration.
The present invention has been achieved in view of the above-mentioned circumstance, and its object is to provide an acceleration sensor which is an improvement of the acceleration sensor proposed in Japanese Patent Application Laid-Open No. 2000-97707 and capable of realizing a further reduction in size and cost while maintaining high performance.
Another object of the present invention is to provide an acceleration sensor which does not limit sliding vibration of a vibrator for the purpose of preventing a lowering of the detection performance.
Still another object of the present invention is to provide an acceleration sensor capable of improving the connectivity between a vibrator and a weight section.
Yet another object of the present invention is to provide an acceleration sensor device having a package structure capable of storing such an acceleration sensor efficiently without deteriorating its detection performance.
An acceleration sensor of the first aspect of the present invention comprises a vibrator provided with an electrode and subject to a sliding vibration; and a weight section connected to the vibrator and supported at a position different from the position of the center of gravity of an assembly of the vibrator and weight section, wherein the weight section is provided with a wiring pattern connected to the electrode, the vibrator detects an angular moment about the support point as sliding vibration, which is exerted in the weight section when an acceleration is applied, and an electrical signal corresponding to the applied acceleration is output from the electrode through the wiring pattern. In this structure, the weight section is provided with the wiring pattern for drawing an electrical signal corresponding to an acceleration to be detected, and also functions as a signal detecting substrate. Therefore, it is not necessary to newly provide a signal detecting substrate, resulting in a simplified structure and a reduction in the cost.
In an acceleration sensor of the second aspect of the present invention, a detection portion for sliding vibration of the vibrator is divided by electrodes which are a plurality of divided electrode parts. Since the detection portion for sliding vibration of the vibrator is divided into a plurality of parts by the electrodes, the detection section of the vibrator can be divided simply, thereby achieving a reduction in the cost.
In an acceleration sensor of the third aspect of the present invention, the detection portion for sliding vibration of the vibrator is divided by the electrodes which are a plurality of divided electrode parts and by a groove connected to the electrodes. Since the detection portion for sliding vibration of the vibrator is divided into a plurality of parts by the formation of the groove, the detection portion of the vibrator is certainly divided and a number of acceleration sensors are readily manufactured, thereby achieving a reduction in the cost.
In an acceleration sensor of the fourth aspect of the present invention, the vibrator has substantially a rectangular parallelepiped shape, and the groove has a depth of not less than 10% of the thickness of the vibrator. Since the groove is formed to have a depth of not less than 10% of the thickness of the vibrator in the process of dividing the detection portion of the vibrator into a plurality of parts by the formation of the groove, it is possible to achieve not only a reduction in the cost, but also an improvement in the detection sensitivity.
In an acceleration sensor of the fifth aspect of the present invention, a position where the detection portion is divided is a position where a charge distribution by the sliding vibration is substantially zero. Since the detection portion of the vibrator is divided at a position where the angular moment of the weight section is substantially zero, i.e., a position where the charge distribution by the sliding vibration of the vibrator is substantially zero, it is possible to achieve not only a reduction in the cost, but also an improvement in the detection sensitivity.
In an acceleration sensor of the sixth aspect of the present invention, the vibrator and weight section have substantially a rectangular parallelepiped shape, and a length (width) of the vibrator in an acceleration detecting direction is not more than a length (width) of the weight section in the acceleration detecting direction. It is therefore possible to reduce an error signal (crosstalk) generated when an acceleration in a direction different from that of an acceleration to be detected is applied, and to improve the S/N ratio.
In an acceleration sensor of the seventh aspect of the present invention, the weight section has substantially a rectangular parallelepiped shape, and has greater thickness and/or length (width) in an acceleration detecting direction in its portion on one side opposite to the other side connected to the vibrator than in its portion on the other side. In the weight section, since the thickness and/or the width of the portion on the side opposite to the vibrator side including the support position is made greater, it is possible to increase the angular moment of the weight section and improve the detection sensitivity.
In an acceleration sensor of the eighth aspect of the present invention, the weight section is constituted by a plurality of members of different materials. It is therefore possible to select the constituent materials of the weight section so as to increase the angular moment of the weight section and improve the detection sensitivity.
In an acceleration sensor of the ninth aspect of the present invention, the weight section has a higher density in its portion on one side opposite to the other side connected to the vibrator than in its portion on the other side. Since the weight section is constructed by using a high-dense material for the portion on the side opposite to the vibrator side, the angular moment of the weight section is increased, thereby improving the detection sensitivity.
In an acceleration sensor of the tenth aspect of the present invention, the vibrator is bonded to the weight section with an anisotropic conductive adhesive. Since the vibrator and the weight section are bonded together with the anisotropic conductive adhesive, it is possible to prevent a short circuit between the divided electrodes, provide a satisfactory connection between the vibrator and weight section, and achieve conductivity only in a desired direction.
In an acceleration sensor of the eleventh aspect of the present invention, the electrical signal is drawn from one of the divided electrodes of the vibrator, which is closer to the position of the center of gravity. Since an acceleration is not detected by a differential output of both the divided electrodes of the vibrator (a differential electrical signal of both the electrodes), but is detected by only the output (electrical signal) of one of the divided electrodes, which is closer to the position of the center of gravity, the number of patterns to be formed in the detection circuit is reduced, thereby achieving a reduction in the cost.
In an acceleration sensor of the twelfth aspect of the present invention, the thinnest portion of the weight section having a substantially rectangular parallelepiped shape is not located on one side of the position of the vibrator, including the position of the center of gravity. Since the thinnest portion of the weight section is placed on the vibrator or on a position extended from the vibrator in a direction opposite to a direction toward the position of the center of gravity, it is possible to reduce crosstalk and improve the S/N ratio.
If some object is placed in the groove of the vibrator, when an acceleration is applied, reciprocal sliding vibration of the vibrator is limited and the detection performance deteriorates. Therefore, the inside of the groove should be kept in a hollow state. Hence, in an acceleration sensor of the thirteenth aspect of the present invention, the inside of the groove is kept in a hollow state by bonding the vibrator and weight section with an anisotropic conductive film. Besides, in an acceleration sensor of the fourteenth aspect of the present invention, a protruding portion with a width of not less than the width of the groove is formed on the weight section, at a position facing the groove, and the groove is covered with the protruding portion, thereby keeping the inside of the groove in a hollow state. According to the thirteenth and fourteenth aspects, there is no possibility that an adhesive for connecting the vibrator and weight section runs into the groove, thereby easily maintaining the inside of the groove in a hollow state. As a result, reciprocal sliding vibration of the vibrator is not limited and high detection performance is obtained.
In an acceleration sensor of the fifteenth aspect of the present invention, the vibrator and weight section are bonded together with an adhesive, and the groove is filled with a filler whose Young""s modulus is smaller than that of the adhesive. If the inside of the groove is in a hollow state, certainly sliding vibration is not limited. However, the process of producing the hollow state is not easy by any means, and it is also hard to say that the process of connecting the vibrator and weight section with an adhesive while maintaining the hollow state is easy. Even when the groove is filled with some filler, if the hardness of the filler is low, sliding vibration is hardly limited. Therefore, the groove is filled with a filler whose Young""s modulus is smaller than that of an adhesive used for connecting the vibrator and weight section. In this case, it is possible to minimize the deterioration of the detection performance and readily perform the process of connecting the vibrator and weight section with an adhesive.
In an acceleration sensor of the sixteenth aspect of the present invention, the groove has a width greater than the widths of the divided detection portions of the vibrator. Since the width of the groove of the vibrator is made greater than the widths of the respective portions where the electrodes are formed, the bonded area other than the electrodes is increased, thereby improving the resistance to shock.
In an acceleration sensor of the seventeenth aspect of the present invention, the vibrator and the weight section are bonded together with an adhesive, and the area of this bonded face is greater than the area of the electrode and/or the wiring pattern. Since the area of the electrode and/or the wiring pattern is made smaller than the bonded area between the vibrator and weight section, even when the electrode and/or the wiring pattern do not easily stick to the adhesive, the vibrator and weight section can be bonded at portions other than the electrode and wiring pattern, thereby achieving a high bonding strength.
In an acceleration sensor of the eighteenth aspect of the present invention, the weight section has a cavity for storing a part of the vibrator. Since a region of the weight section connected to the vibrator has a cavity structure, even when its portion connected to the vibrator is made thinner so as to improve the detection sensitivity, the weight section is not twisted by an applied acceleration, thereby limiting an increase of crosstalk and improving the resistance to shock.
In an acceleration sensor of the nineteenth aspect of the present invention, the vibrator is a single crystal piezoelectric element. Since a single crystal piezoelectric element is used for the vibrator, it is possible to reduce crosstalk and improve the S/N ratio.
In an acceleration sensor of the twentieth aspect of the present invention, the single crystal piezoelectric element is an X-cut plate of lithium niobate (LibO3). Since the X-cut plate of LiNbO3 which does not have an electromechanical bonding in a thickness direction is used as the vibrator, it is possible to reduce crosstalk and improve the S/N ratio.
An acceleration sensor device of the twenty first aspect of the present invention comprises an acceleration sensor as described above; and a package, including a base provided with a wiring pattern and a cap covering the base, for storing the acceleration sensor therein. Since the acceleration sensor is stored in the package including the base provided with the wiring pattern and the cap, it is possible to readily perform the process of storing the acceleration sensor and to easily construct a circuit for drawing an electrical signal.
An acceleration sensor device of the twenty second aspect of the present invention includes in a package a detection circuit for detecting an acceleration based on an output electrical signal. Since the detection circuit is stored in the package together with an acceleration sensor, it is possible to improve the S/N ratio.
In an acceleration sensor device of the twenty third aspect of the present invention, a part of the weight section is sandwiched by a package. It is therefore possible to readily provide an electrical connection between the weight section and package and to reduce the size of the device.
In an acceleration sensor device of the twenty fourth aspect of the present invention, a part of the weight section and a part of the vibrator are sandwiched by the package. It is therefore possible to readily provide an electrical connection between the weight section and package and to reduce the size of the device.
In an acceleration sensor device of the twenty fifth aspect of the present invention, the part of the weight section sandwiched by the package is a portion located on one side of the position of the vibrator opposite to the other side including the position of the center of gravity. Since the vibrator and the portion of the weight section located on one side of the position of the vibrator opposite to the other side including the position of the center of gravity are sandwiched by the package, even though they are sandwiched by the package, the sandwiched portions are apart from the position of the center of gravity on which an acceleration applies. Therefore, the detection sensitivity is not lowered.
In an acceleration sensor device of the twenty sixth aspect of the present invention, the length of the part of the weight section sandwiched by the package is not more than the length of the vibrator. It is therefore possible to improve the detection sensitivity.
In an acceleration sensor device of the twenty seventh aspect of the present invention, the vibrator has a package-side electrode, the package is provided with a wiring pattern connected to the electrode, the vibrator and package are bonded together with an adhesive, and the area of the bonded face is larger than the area of the electrode and/or the wiring pattern. Therefore, even when the electrode and/or the wiring pattern do not easily stick to the adhesive, the vibrator and package are bonded together at portions other than the electrode and wiring pattern, thereby achieving a high bonding strength.
A method of fabricating an acceleration sensor of the twenty eighth aspect of the present invention comprises the steps of forming a groove in a vibrator; applying a material produced by dissolving a powder in a volatile solvent to the groove; evaporating the volatile solvent; and connecting the vibrator and a weight section with an adhesive. The powder layer functions as a cap to prevent the adhesive from entering the groove, thereby maintaining the inside of the groove in a hollow state.
A method of fabricating an acceleration sensor of the twenty ninth aspect of the present invention comprises the steps of forming a groove in a vibrator; inserting a structural body into the groove; connecting the vibrator and weight section with an adhesive; and removing the structural body. This method can prevent the adhesive from entering the groove and maintain the groove in a hollow state.
The above and further objects and features of the invention will more fully be apparent from the following detailed description with accompanying drawings.

Acceleration sensor, acceleration sensor device, and method of fabricating an acceleration sensor


An electrical circuit comprising at least two negative capacitance insulators connected in series, one of the two negative capacitance insulators is biased to generate a negative capacitance. One of the negative capacitance insulators may include an air-gap which is part of a nanoelectromechnical system (NEMS) device and the second negative capacitance insulator includes a ferroelectric material. Both of the negative capacitance insulators may be located between the channel and gate of a field effect transistor. The NEMS device may include a movable electrode, a dielectric and a fixed electrode and arranged so that the movable electrode is attached to at least two points and spaced apart from the dielectric and fixed electrode, and the ferroelectric capacitor is electrically connected to either of the electrodes.

Nanoelectromechanical systems (NEMS) are seen as one of the most promising candidates for next generation extreme low power electronics that can operate as a versatile switch/memory/sensor/display element. The NEMS devices have often been mentioned as one of the most promising candidates in ITRS roadmap for a number of emerging device categories. The effective zero standby power dissipation and low subthreshold swing make it an ideal candidate for a logic switch (NEMFET), its intrinsic hysteresis suggests potential as a non-volatile memory element (NEMM), and its high quality factor and sensitivity to changes in mass/stiffness promise applications as RF resonators or nanobiosensors.
One of the main challenges toward this goal lies in the fabrication difficulties of ultra-scaled NEMS which is required for high density integrated circuits. It is believed that fabricating and operating a NEMS with an airgap below a few nanometers will be extremely challenging due to factors including surface roughness, non-ideal forces and tunneling. A Micro/Nano electromechanical system (M/NEMS) consists of a pair of electrodes one fixed and the other movable separated by an airgap. However, the most difficult challenge inhibiting the integration of these devices in next generation chips has been the reliable scalability of NEMS devices. For example, a low power memory/switch requires sub-1V actuation (Vpi), which can be achieved only if the airgap is scaled to a few nanometer range. Such an extreme scaling poses a difficult fabrication challenge. Moreover, the reduced airgap leads to the introduction of many non-ideal physical effects, such as the tunneling current (for less than 2 nm) which in turn degrades the subtreshold swing (SS) and standby power dissipation, the surface forces (for example, Van der Wall and Casimir) causing stiction, etc. Therefore, although NEMS switches with a 4 nm airgap (sub-1V Vpi) using a pipe-clip structure have been reported, the most advanced devices based on conventional geometry rely on an airgap of 15 nm (with a corresponding pull-in voltage, Vp13V).
Ferroelectric (FE) negative capacitors are known. Recently, Salahuddin and Datta has reported a ferroelectric negative capacitor connected in series with a classical gate oxide transistor in which the gate voltage was amplified and thereby reduced the sub-threshold swing below the 60 mV/decade limit. It is well-known that an FE capacitor is characterized by a negative capacitance around zero charge, but the capacitor by itself cannot be operated at this unstable point. Operation of an FE capacitor around this negative capacitance regime is possible only if the overall system is stabilized by adding a series capacitor. The stability comes from the fact that the charge state of the combined structure is determined by, not the FE alone, but the energetics of the overall structure. An elementary circuit analysis shows that, in the negative capacitance regime, the voltage across the FE capacitor can also be negative, even when a positive voltage is applied across the combined structure. Since the total applied voltage is constant, therefore, the voltage across the remaining series capacitor is higher than the applied voltage. Such voltage amplification is the basis of sub-60 mV/decade operation of the negative capacitance field effect transistor (NCFET) where the gate stack contains the FE film, and the remaining gate and the channel capacitance act as the series capacitor that stabilizes the FE film.
Another problem involves switches, which are the most basic component of integrated circuit (IC) technology. The sub-threshold swing (S) characterizes the switching characteristics of a switch where S=0 mV/decade corresponds to an ideal switch. However, current IC technology relies on field effect transistors (FETs) which are non-ideal in practice. The switching characteristics of a classical FET are far from being ideal and thermodynamics dictate that S cannot be lower than 60 mV/decade. Alternative approaches using devices with gate insulators with negative capacitance (NC) that have S<60 mV/decade such as Ferroelectric-FETs and suspended gate FETs have been developed. However, these approaches have not been able to achieve an ideal switching characteristic of S=0 mV/decade. Moreover, existing approaches of 0 mV/decade are not hysteresis-free. Therefore, improvements are needed in the field.

NEMS devices with series ferroelectric negative capacitor


A processing device of a server executing an application establishes a network connection to a client device having a smart card, detects a program call associated with an authentication of a user of the client device for accessing the application, and determines, based on the program call, whether the smart card is a remote smart card for the server. Responsive to determining that the smart card is the remote smart card, the processing device redirects the program call to the client device via a communication channel of the network connection and authenticates, by the server, the user of the client device in view of data returned by the program call, as if the remote smart card were local to the server.

Smart cards can be used to authenticate a user, for example, when the user logs into a network and/or computing system. Smart cards can provide a strong form of authentication from the use of cryptography-based identification and proof of possession when authenticating the user. Smart card authentication is a two-factor authentication method in that (1) a user presents a smart card, and (2) the user provides a personal identification number (PIN). In the case of smart cards, a malicious person would have to obtain both the smart card of the user and the PIN of the user to impersonate the user.
FIG. 1 is an example of conventional prior art system architecture 100 for authenticating a user 101 via a local smart card 103. A user 101 that attempts to log on to a computer (e.g., computing machine 120) generally enters the user's credentials, which are used to verify the user's identity. For smart card logons, a user's credentials and/or one or more values derived from the user's credentials are contained on the security chip of the smart card 103, which is read by a device, such as a smart card reader. A user 101 can insert a smart card 103 into a smart card reader associated with a computing machine 120, and a Windows® logon service (WINLOGON) 121 prompts the user 101 to enter a PIN (rather than a username and password) as input via a graphical user interface being displayed on the computing machine 120. WINLOGON 121 can reside on the computing machine 120, which is the same computing machine 120 that is coupled to the smart card 103, to authenticate the identity of the user 101 to allow the user 101 to log into an operating system (e.g., Windows® operating system) and/or applications that may be executing on the computing machine 120.
WINLOGON 121 can pass the PIN to an LSA application programming interface (API) 123 to communicate to the Local Security Authority (LSA) 126. The LSA 126 is a protected system process that can authenticate and log users (e.g., user 101) on to the computer (e.g., computing machine 120). The LSA 126 can include a subsystem, Local Security Authority Subsystem Service (LSASS) 127, that is responsible for enforcing the security policy on the system (e.g., computing machine 120). The LSASS 127 can verify users (e.g., user 101) logging on to a computing system 120 (e.g., Windows® computer) or a server. The LSASS 127 can be a process in an operating system (e.g., Windows® operating system).
The LSASS 127 can create an access token for an authenticated user. The PIN can be passed to the LSASS 127, which can generate and return an access token. The access token can be used to impersonate an authenticated user (e.g., user 101).
The logon information to authenticate the user 101 with a domain controller 122 can be stored in an encrypted format on the smart card 103. The smart card 103 can contain a microprocessor and non-volatile memory that stores the user's logon information, private key 108, digital certificate 105 that includes a public key 107, and other private information. A public key infrastructure (PKI) can create secure communications. PKI is asymmetric in that a key pair is used to create the secure communications. A public key 107 of the user 101 can be used to encrypt data and a private key 108 of the user 101 can be used to decrypt data. PKI uses digital certificates (e.g., certificate 105) that include a public key 107 of a user 101 for encrypting data. The public key 107 can be made publicly available to one or more entities (e.g., domain controller 122) for creating secure communications with a respective entity. The private key 108 is not made publicly available, and is kept secret by the owner (e.g., user 101).
The LSA 126 can use the PIN to access the smart card 103. The LSASS 127 can issue one or more program calls (e.g., smart card API calls 124) to the native smart card API 125 (e.g., native Windows® Smart Card (WinSCard) API) to interact with the local smart card 103 to obtain the certificate 105 containing the public key 107 from the smart card 103. The native smart card API 125 (e.g., WinSCard API) is used by applications to interact with smart cards (e.g., smart card 103). The LSASS 127 can pass the PIN to the smart card 103 via the smart card API calls 124 made to the native smart card API 125.
The smart card 103 can confirm that the PIN is valid if the smart card 103 can use the PIN to successfully decrypt the user's logon information that is stored on the smart card 103. If the PIN is valid, the smart card 103 allows the LSASS 127 to obtain the certificate 105 containing the public key 107 that is stored on the smart card 103 via the native smart card API 125. The certificate 105 can be an X.509 (e.g., X509 v3) certificate. In some implementations, if the PIN cannot successfully decrypt the user's logon information for a number of times, for example, because the PIN is incorrect, the smart card 103 is locked.
The LSASS 127 can send the user's certificate 105, which contains the user's public key 107, along with other user information to a domain controller 122 as pre-authentication data in an initial authentication request. The domain controller 122 can validate the certificate 105, extract the public key 107, and use the public key 107 to encrypt a logon session key. The domain controller 122 returns the encrypted logon session key to the computing machine 120. If the computing machine 120 is in possession of the private key 108 of the user 101, the computing machine 120 can use the private key 108 to decrypt the logon session key. The computing machine 120 and the domain controller 122 can use the logon session key in further communications between each other.
This traditional mechanism can only be used for local smart card authentication, where the smart card and authentication server reside on the same computing machine. If the user 101 needs to access an operating system and/or applications on a remote computing machine, the described mechanism cannot provide for remote smart card authentication.
As described above, current solutions utilizing the LSA Subsystem Service (LSASS) do not provide for remote smart card authentication. Remote Desktop Protocol (RDP) is known to be used in a Remote Desktop Services (RDS) environment to authenticate remote smart cards. Remote Desktop Services (RDS) is a Microsoft® component that allows a user to take control over a remote computer or virtual machine over a network connection. A Remote Desktop Session Host (RDSH) server is an RDS component that hosts Windows® based programs or a full Windows® desktop, which remote RDS clients can access. Users can connect to an RDSH server to run programs, to save files, and to use network resources on that server. Remote Desktop Protocol provides a user with a graphical interface to connect to an RDSH server over a network. A smart card can be used to remotely authenticate a user to an RDSH server.
FIG. 2 is an example of conventional prior art RDS system architecture 200 for providing, using RDP, remote smart card authentication to provide a user with access to applications on an RDSH server. Users (e.g., user 201) can connect, via RDS clients (e.g., client device 210) and an RDP connection 240 over network 250, to an RDSH server 230 hosted on a computing system 220 to run applications 231 or full desktops hosted on the RDSH server 230. For example, the applications 231 may include an email application, a word processing application, a spreadsheet application, a presentation application, etc. that may be used by one or more users 201 and client devices 210.
In order to provide RDS, there needs to be the RDP connection 240 between the client device 210 and the RDSH server 230 to allow the client device 210 to access the applications 231 being hosted by the RDSH server 230. For security reasons, the user 201 needs to be authenticated to the RDSH server 230 before logging into an RDP session. Traditionally in a Windows® 2003 environment, a user 201 must first establish the RDP connection 240 between the client device 210 and the RDSH server 230 prior to authenticating with the RDSH server 230. The user 201 can initiate the RDP connection 240 via a graphical user interface (GUI).
Logging into an RDP session using simply a user name and password generally does not provide strong authentication and may not satisfy, for example, a company's security policies. To help strengthen security, there may be a need to replace the traditional mechanism of using a user name and password for logging into an RDP session with a more robust form of authentication, such as remote smart card authentication.
Some traditional technology, such as Network Level Authentication (NLA), can allow the user 201 to be authenticated via the remote smart card 203 before an RDP connection 240 is established. NLA is a technology used in Remote Desktop Services or Remote Desktop connection that requires the connecting user (e.g., user 201) to be authenticated before a session is established with the server (e.g., server 230). NLA uses Credential Security Support Provider protocol (CredSSP), and requires that CredSSP be enabled in a system registry. The operating system of the client device (e.g., client device 210) has a CredSSP client component and the server (e.g., server 230) has a CredSSP server component. NLA delegates the user's credentials from the client through CredSSP client component and prompts the user (e.g., user 201) to authenticate before establishing a session on the server (e.g., server 230). NLA, however, is a limited solution in that NLA does not support other credential providers.

This patent is subject to a terminal disclaimer.


An operating method of a variable resistance memory device including a pre-read step which may include the steps of: reading a first reference cell using a first reference voltage; reading a second reference cell using a second reference voltage; and setting a third reference voltage based on the first and second reference voltages; and a main read step of reading a selected memory cell using the third reference voltage.

1. Technical Field
The present invention generally relates to a semiconductor memory device, and more particularly, to a variable resistance memory device and an operating method thereof.
2. Related Art
In general, a semiconductor memory device is classified into a volatile memory device and a nonvolatile memory device. The volatile memory device loses data stored therein when power supply is cut off, but the nonvolatile memory device maintains data stored therein even though power supply is cut off. The nonvolatile memory device may include various types of memory cells.
The nonvolatile memory device may be divided into a flash memory device, a ferroelectric RAM (FRAM) using a ferroelectric capacitor, a magnetic RAM (MRAM) using a tunneling magneto-resistive (TMR) layer, a phase change memory device using chalcogenide alloys and the like, depending on the structure of memory cells. In particular, the phase change memory device is a nonvolatile memory device using phase change based on temperature change, that is, resistance change. For this reason, the phase change memory device is also referred to as a variable resistance memory device.
The phase change memory device includes memory cells formed of a phase change material, for example, a chalcogenide alloy which is a germanium(Ge)-antimony(Sb)-tellurium(Te) mixture (GST) (hereafter, referred to as a GST material). The GST material has an amorphous state having a relatively high resistivity and a crystalline state having a relatively low resistivity. The memory cell of the phase change memory device may store data '0' corresponding to the amorphous state and data '1' corresponding to the crystalline state. The GST material may be heated to program the data corresponding to the amorphous state or the crystalline state into the memory cell of the phase change memory device. For example, the amorphous state or the crystalline state of the GST material may be controlled by adjusting the magnitude of a current for heating the GST material and the application time of the current.
However, as the time elapses after the program operation, resistance drift may occur in the GST material forming the memory cell of the phase change memory device. When the resistance drift occurs, the resistance value of the GST material does not maintain a fixed value, but increases. The resistance change of the GST material may reduce a sensing margin of the memory cell, thereby reducing the reliability of the phase change memory device.

Variable resistance memory device and operating method thereof


A retarding conveyor for cargo such as pallets is disclosed. The conveyor is of the type which can be driven in sections by intermediate rollers, the latter being adjustable into a driving position or an idle position by feelers extending into the path of motion of the cargo. Respective sections of the conveyor comprise at least two parallel uninterrupted traction devices which are deflected at the ends of the section by guide wheels joined together for rotation, supports being provided on the conveyor for supporting the traction devices to carry the cargo and at least one of the guide wheels being driven by an intermediate roller.

The present invention relates to a retarding conveyor for cargo such as pallets, comprising a conveying means which can be driven in sections and carries the cargo, respective sections of the conveying means being driven by intermediate roller means driven by rotating drive means, the intermediate roller means being adjustable into a driving position or an idling position by feelers extending into the path of motion of the cargo.
According to DOS [German Unexamined Laid-Open Application] No. 2,517,015, a roller train for the conveying and stowing of cargo has been known wherein supporting rollers rotatable at right angles to the conveying direction are provided for the carrying and transporting of the cargo. Each supporting roller is associated with an intermediate roller, which latter connects, in the driving position, the supporting roller with the drive means and thus drives the supporting roller. The drive means is fashioned as a chain which is engaged by the intermediate roller with a sprocket wheel, while gear-like wheels can also be arranged for the drive transmission from the intermediate roller to the supporting roller. The intermediate rollers are joined into groups by an adjusting rail so that they can be placed into the driving position or into the idling position by the connected feeler. Thus, several supporting rollers and an identical number of intermediate rollers are provided in each section. Each of these rollers must be supported and/or arranged so that it is readily rotatable and maximally free of servicing or in need of only minimum servicing. Accordingly, for a stow roller train, a high number of such rollers is necessary, which render such a roller train relatively expensive. A stow roller train is also known from U.S. Pat. No. 3,066,788 wherein the supporting rollers of one section are driven in combination by one chain. Between the respective sections one intermediate roller is arranged which can be vertically adjusted, wherein the intermediate roller in the upper position assumes the driving position with contact on the first and last drive wheels of neighboring sections and in the lower position assumes the idling position. The intermediate rollers are constantly driven separately. Although in this stow roller train the number of intermediate rollers is reduced, the number of supporting rollers has been retained. Furthermore, the arrangement of the intermediate roller is unfavorable, since the adjusting force for adjusting the roller into the drive position must also include the contact pressure for producing the frictional connection between the intermediate roller and supporting rollers, i.e. a relatively high contact force is required. The conventional retarding conveyors are consequently voluminous in construction, expensive in servicing, and correspondingly costly in initial investment and upkeep.
Therefore, it is an object of the present invention to simplify a retarding conveyor while retaining the conventional high conveying and stowing volume.
This and the other objects of the present invention are attained by providing that respective sections on the conveying means in a retarding conveyor of the aforementioned type comprise at least two parallel, uninterrupted traction means, which are deflected at the ends of the section by guide wheels joined together for rotation, support means being provided on said conveyor for supporting said traction to carry cargo, and at least one of the guide wheels being driven by intermediate roller means.
An especially uniform movement of the cargo results in a further embodiment of the invention by arranging the feeler, which is fashioned as a pivotably supported roller, between two neighboring sections and by the fact that the feeler in its enforced idling position serves, due to its resting on abutments affixed to the frame, as a support for the cargo.
A high drive transmission is attained according to another feature of the invention by the fact that the traction means of the conveying means and the drive means are constructed as chains, and the intermediate roller, in addition to a sprocket wheel engaging into the drive means, also has a gear wheel which, in the driving position, meshes with a drive gear wheel connected for rotation with a guide wheel.
Advantages obtained by the present invention reside particularly in that the number of the supporting and driving rollers is greatly reduced. Each section requires, in this arrangement, merely the guide wheels for the chain hoists of the conveying means and only one intermediate roller to set the coupled together chain hoists into operation. With the reduced number of rollers, the possible error sources have likewise been drastically decreased. Thereby, such a retarding conveyor is simplified to a high degree as compared to the conventional retarding conveyers with respect to structure as well as function. On the other hand, by an adapted control of the sections, a close conveying sequence and stow density can be attained which correspond to those of the known stow roller trains. Since the chain hoists support the cargo along its entire length, a high acceleration is obtained in addition to a secure positioning of the cargo, and thus a high conveying speed results even at brief conveying periods. The retarding conveyor according to the present invention, therefore, not only represents a simplification of a retarding conveyor, but also offers, in addition to a lesser need for servicing, a high and thus economical exploitation of the stowing space as well as the driving energy.


An enzyme-capture assay (ECA) for rapid identification of Escherichia coli (E. coli) in clinical samples comprising contacting a clinical sample which is suspected to contain E. coli with an immobilized antibody against .beta.-D-glucuronidase which then catalyzes an enzyme substrate to produce a fluorescent product is disclosed.

The isolation of any significant microorganism from a blood culture is an occurrence that requires careful evaluation by clinicians, and prompt action is usually necessary. The incidence of bacteremia and fungemia had been reported to be 3.4-28/1,000 hospital admissions and was estimated to average 10/1,000 (1%) in the United States (1). The five common isolates from blood cultures were Escherichia coli (E. coli), Staphylococcus aureus, Streptococcus pneumoniae, Klebsiella pneumoniae, and Pseudomonas aeruginosa (2). E. coli is the most important gram-negative bacterium in clinical microbiology laboratories. It is isolated frequently from bacteremic episodes (2, 3, 4, 5, 6), either as a pure culture or as part of a mixed culture. The isolation rate of E. coli can be as high as 40% among the gram-negative bacteria found in bacteremia (6). During the period 1991-1992, in one of the inventors' hospital (National Cheng-Kung University Hospital, Tainan, Taiwan), isolates of E. coli accounted for 21.7% of all bacteria causing bloodstream infections (unpublished data). In another study, E. coli is responsible for 28.4% of all isolates from bacteremic episodes in the pediatric department (7). In view of the high incidence and mortality rate (2), a rapid identification method of E. coli in blood specimens is of clinical importance.
The common practice used in hospitals to identify E. coli is to subculture blood specimens at intervals after an incubation period of 12 hours to 2 weeks (3, 8), and at the time when Gram stain is positive or bacterial growth is apparent (e.g. turbidity, gas production or hemolysis). The subculture and identification steps, however, normally take at least 24 hours. In view of the high incidence and high mortality rate of bacteremia caused by E. coli, in addition to the conventional culture protocols, it is plausible, when the growth of gram-negative bacteria is found, to parallelly perform specific assays to rapidly identify E. coli in blood cultures so that relevant treatment can be started earlier than the conventional identification systems.
Since Kilian and B ulow (9) described the activity of a .beta.-D-glucuronidase (GUD) in restricted species belonging to Escherichia, Shigella, and Salmonella in 1976, this property has been widely used for the detection and identification of E. coli (10, 11, 12, 13, 14) in the food and clinical microbiology laboratories. Most reports incorporated 4-methylumbelliferyl-.beta.-D-glucuronide (MUG) as a fluorogenic substrate of GUD in the media. Some other bacteria (Yersinia, Flavobacterium, staphylococci, and streptococci) are also positive for this enzyme (15, 16, 17), and false-positive reactions are sometimes caused by the animal tissues which contain the enzyme. For this reason, an enzyme-capture assay (ECA) for detection of E. coli in oysters was developed (15). Anti-GUD antibodies coated on the microtiter plate were used to capture the enzyme produced by E. coli present in the food samples, followed by the addition of fluorogenic or chromogenic substrates to demonstrate the GUD activities. Under this condition, cross-reactions are only caused by the members of Enterobacteriaceae.
Although the direct incorporation of a fluorogenic substrate of GUD into a culture media is a convenient and fast way to detect E. coli present in specimens, the practice is impossible for blood cultures, due to the deep red color of blood which masks the fluorescence generated by GUD on the substrate. Enzyme-capture assay seems to be a good choice for solving this problem.
Recently, Husson et al. (18) have described an alkaline phosphatase capture test for the identification of E. coli and Shigella species in blood cultures and urine specimens. Although the specificity (96.8%) is high for detecting E. coli from urine specimens, the sensitivity is relatively low (91%) for blood cultures.
It is still in grave need to develop a rapid method for identifying E. coli in clinical samples with sufficiently high sensitivity and specificity to ensure earlier commencement of antimicrobial treatments.

Enzyme-capture assay (ECA) for the identification of Escherichia coli in clinical samples

Food Industry Research and Development Institute


A method of detecting an overcoating rubber flowed in a space between a core member and a securing metal fitting of a polymer insulator having the core member, the overcoating arranged around the core member and the securing metal fitting fixed to at least one end of the core member, is disclosed. The method includes the steps of: applying a torque in a circumferential direction to the securing metal fitting, after forming the overcoating rubber but before fixing the securing metal fitting to the core member; deforming an index provided on a surface of the overcoating; and detecting whether the overcoating rubber is existent or not in the space between the securing metal member and the core member in response to a deforming extent indicated by the index.

1. Field of the Invention
The present invention relates to a method of detecting an overcoating rubber flowed in a space between a core member and a securing metal fitting of a polymer insulator having the core member, the overcoating arranged around the core member and the securing metal fitting fixed to at least one end of the core member.
2. Description of the Related Art
Generally, there is known a polymer insulator comprising a core member, overcoating arranged around the core member, and securing metal fitting fixed to at least one end of the core member. In order to keep a seal performance between the securing metal fitting and the overcoating, when such a polymer insulator is manufactured, the applicant proposed, in Japanese Patent Application No. 9-56297, a method of manufacturing the polymer insulator, in which an overcoating rubber for forming the overcoating is formed under a condition such that the securing metal fitting is set to the core member without being fixed, the securing metal fitting and the overcoating rubber are preliminarily cured, and the securing metal fitting is clamped to the core member.
In the manufacturing method mentioned above, since the securing metal fitting is simply set to the core member, in the case of forming the overcoating rubber, a V-packing is arranged in the space between the core member and the securing metal fitting, thereby preventing a flow of the overcoating rubber into the space. However, if the overcoating rubber should flow into the space between the core member and the securing metal fitting, the tensile strength of the polymer insulator is decreased. Therefore, it is necessary to detect whether the overcoating rubber has flowed into the space or not by a non-destructive manner.
As a non-destructive detection methods, there are X-rays, an ultrasonic flaw detection method, a method using acoustic emission, and so on. However, in the case of detecting whether or not the overcoating rubber which is flowed into the space between the core member and the securing metal fitting, as existent, it is not possible to detect the overcoating rubber in the space by the method of using X-ray, the ultrasonic flaw detection method and the method of using acoustic emission.

Method of detecting overcoating rubber flowed in space between core member and securing metal fitting of polymer insulator


A method and apparatus for printing and scoring media in a printing system. In one embodiment a scoring pattern is based upon input by the user on a graphical user interface. The system typically incorporates a controller that drives a scoring printer having a scoring head with one or more pins or wires that impact the surface of media and weaken the media. By creating a predetermined pattern of impacts, the media is weakened along a region or line for subsequent separation.

Printers have been equipped with cutting devices so that a printed media can be cut at the end of the printing operation without removing the media from the printer. A typical system involves passing a rotary or fixed cutting blade across the media after the printing operation has been completed. Examples of these systems are disclosed in U.S. Pat. Nos. 5,363,123, 5,881,624, 5,296,872, and 5,882,128. These systems are designed to cut along a straight line across the media after the printing operation. However, if a user wishes to cut a line that is curved or angular, or cut out a closed shape from the media, these systems are inadequate. The user must cut the media in a separate operation after removing the media. U.S. Pat. No. 6,117,061 discloses system for printing upon removable portions of a two-dimensional media sheet. The removable portions are removed after printing and folded into three-dimensional shapes. This system, however, requires that the media be first scored or perforated before it is inserted into the printer, so that the removable portions can be removed from the media after printing.
What the prior-art systems lack is a means integrated with the printer that allows complex shapes to be cut or scored into the media as part of the printing operation.

Hewlett-Packard Development Company, LP.


A conveyor system (10) with an overhead rail (11) has trolleys (12) with an upper drive wheel (13) and lower bucking rollers (15,16) of which at least one is fitted with a spring (17) to provide the necessary traction between drive wheel (13) and rail (11) along sloping paths. The rail (11) has a first unvarying thickness in its horizontal sections (20) and a second thickness, greater than the first, in its sloping sections (21), while the radiused sections (22,23) between horizontal sections (20) and sloping sections (21) have a variable thickness sized to hold substantially constant the compression of the spring (17) along the entire radiused sections (22,23) and in particular, at a value substantially equal to that provided by the spring along the sloping sections (21).

In the art of internal transportation in factories, there are often used self-powered industrial material handling systems, which consist of a suspended monorail on which run powered trolleys powered through an electric distribution line arranged along the rail.
The trolleys usually have a drive wheel above the monorail and bucking rollers placed below it. Traction is thus assured by the adherence of the powered upper wheel on the monorail. This adherence is usually sufficient for movement on the level or along slight rises due to the weight of the trolley itself including the load carried by it and pulling down on the drive wheel.
For sloping sections with relatively steep slopes there have been proposed lower bucking rollers equipped with a pressure means such as a spring-loaded system that pushes the rollers toward the rail so as to increase the adherence or traction of the drive wheel on the rail as described for example in Italian patent No. 202,807 in the name of FATA European Group.
The use of bucking rollers, however, causes problems due to variations in the compression of the pressure means in the curved and radiused sections between sections with different slopes. The bucking rollers are usually two in number and are positioned along the chords of the curved sections. Hence if they are inside a curve they tend to draw away the powered wheel and if they are on the outside they draw near it. Consequently, in the former case, the springs are more compressed and in the latter case they are less compressed slope variations.
To prevent these compression differences from causing excessive and deleterious variations in traction, there have been proposed various solutions which, however, suffer from several drawbacks.
For example, there have been proposed thrust springs with a length much greater than the extension caused by variations in the rail curvature so that the resulting thrust variation is as limited as possible. A solution of this type, however, suffers from the size of the springs, which penalizes the compactness of the trolley design and requires greater spacing of the loads from the rail, which thus must be placed in a higher position. To obviate at least partially the problem, there have been used linkages and transmissions added to the bucking system or springs with several concentric stages with an increase in complexity and hence cost of the trolley, introducing also greater probability of breakdown.
Thrust means for the bucking wheels having substantially constant operation have the further disadvantage of supplying the same friction necessary for rising travel even during travel on horizontal sections where the weight of the trolley would be sufficient to ensure adherence of the drive wheel. This uselessly stresses the mechanical parts of the trolley and increases wear on the rolling members and the rail.
The general object of the present invention therefore is to obviate the drawbacks mentioned above by proving a conveyor system of the self-powered type which, while it can have trolleys of limited size and complexity, allow the use of ascending and descending ramps with relatively steep slopes without additional movement means and without introducing disadvantages for level travel.

Material conveyor system comprising powered trolleys on an overhead rail, the rail having varying thickness curved rail sections to maintain a constant spring compression on a roller during traversal of grades


An indication to replicate, for a second storage resource, a volume that is stored at a first storage resource may be received. A snapshot of the volume that is stored at the second storage resource may be identified. Data with operations to data blocks of the volume may be identified. A sequence number range, containing one or more sequence numbers, associated with the snapshot of the volume that is stored at the second resource may be received. Furthermore, a portion of the data associated with the operations to the data blocks of the volume based on the sequence number range that is associated with the snapshot of the volume that is stored at the second resource may be received to replicate the volume at the second storage resource.

Data replication is a process to copy data from a source storage system to a target storage system. For example, the data may correspond to a volume of data that is present at the source storage system and is transmitted to the target storage system for storage at the target storage system. The volume may be represented by multiple snapshots that represent data of the volume at a particular point in time. To replicate a volume that is represented by multiple snapshots, each of the snapshots from the source storage system may be transmitted to the target storage system and subsequently stored at the target storage system.

Efficient volume replication in a storage system


A wheel assembly for a baby carriage is provided comprising two wheels mounted on opposing ends of a shaft supported by a shaft holder fixed at an end of a supporting rod of a baby carriage. The shaft is coupled to the two wheels and a combining disc is secured to the shaft by small projections inserted within an annular groove formed in the shaft. A cap covers a recessed aperture of each wheel and is pressed inwardly to compress the combining disc for disengagement of the combining disc from the shaft and the wheel from the shaft.

1. Field of the Invention
This invention pertains to wheel assemblies for baby carriages.
2. Prior Art
A conventional or prior art wheel assembly for baby carriages is shown in FIGS. 4-6 and includes a wheel assembly consisting of two wheels 8, 8' supported on a shaft holder 9 which is fixed pivotally at one end of a supporting rod 10. A shaft 7 is inserted through the wheels 8, 8' and the shaft holder 9 between both wheels 8, 8' and then is inserted through a combining disc 72 which has an engaging groove 71 for a pulling ring 73 insert for preventing removal of the wheel 8. A cap 74 is provided to enclose and cover the assemblage.
The prior art wheels 8, 8' may be assembled or disassembled by means of the pulling ring 73 engaging the groove 71 or being pressed down to prevent disengagement from the groove 71.
However, this conventional or prior art wheel assembly is considered to have the following disadvantages:
1. Such prior art wheel assemblies have a plurality of complicated component combinations such as a combining disc having a cylindrical portion 75 and an annular hook 76 as well as wheels having ridges 77 which increases the cost for these structures.
2. In such prior art structures, the pulling ring and the shaft are made of metal which is liable to rust owing to an extended period of use in an external environment or to a defective original anti-rust treatment which results in the pulling ring being operatively defective causing difficulty in disassembling the wheel.
3. Provision of the combining disc dictates that the shaft holes of the two wheels are of different size, which results in higher manufacturing costs.


A system for stabilization of a shoreline includes a plurality of stakes and a flexible sheet switchable between an open configuration and a folded configuration. The sheet has a first edge and a second edge, and each edge includes a channel in which an anchoring rope runs through. An organic material is disposed in a body region of the flexible sheet when the sheet is in the folded configuration. The first edge and second edge are secured to the plurality of stakes by the anchoring ropes.

The present invention relates generally to a method and system for creating and restoring eroded shorelines, and for further sustaining transplanted and indigenous plants and vegetation thereon, and for providing filtration for the affected body of water.
Shorelines surrounding many bodies of water have become unhealthy in recent years. The unhealthy nature of shorelines, such as shorelines surrounding ponds and lakes have suffered due to many reasons such as residential and commercial development, increased amounts of runoff dues to non-permeable surfaces, loss and removal of native shoreline vegetation, and many other reasons.
Unhealthy shorelines often result in deteriorating water conditions that are harmful to aquatic life. Absent healthy shorelines, silt, nitrates, phosphates, and other soluble and particulate matter are often able to flow unrestricted in bodies of water. These bodies of water may fill with silt and particulate matter, which may damage the ecosystem for aquatic life. Aquatic ecosystems may also be damaged, or otherwise altered form a healthy state, increasing algae growth and other invasive plants and aquatic life to flourish. The result is often an unhealthy body of water that not only disrupts or destroys naturally occurring aquatic ecosystems, but also disrupts recreation and other uses of these altered bodies of water.
Commonly owned U.S. Pat. No. 8,070,387 discloses one apparatus and method for shoreline stabilization, restoration and runoff filtration, the entire content of which is incorporated by reference herein.
There remains a need in the art for improved methods and systems for shoreline stabilization and management.
Without limiting the scope of the invention, a brief summary of some of the claimed embodiments of the invention is set forth below.

Shoreline stabilization, restoration, and runoff filtration


An impregnated electric wound capacitor has a dielectric consisting of synthetic foils which are wound with paper tapes. The synthetic foils are impregnated with mineral oil and swell such that a residual impregnation gap remains between dielectric and the paper tapes. The existance of such a residual impregnation gap assures that re-impregnation will occur after the capacitor is subjected to temperature changes during operation or after a gas pocket develops due to a partial blow-out.

1. Field of the Invention
The present invention relates to impregnated electric wound capacitors.
2. Description of the Prior Art
Impregnated electric wound capacitors are known in the art, such as German Auslegeschrift 18 15 478, which have a dielectric consisting of swollen polypropylene foils impregnated with mineral oil and whose electrodes consist of paper tapes metalized on both sides and arranged in the field-free space. The polypropylene foils of the capacitor generally exhibit a minimum swelling of 0.3 .mu.m. The swelling of the foils is accordingly dimensioned in such a manner that practically no residual impregnation gap is present in the winding after the swelling is completed.
The absence of a residual impregnation gap means that re-impregnation of the winding is no longer assured after the winding is subjected to stresses of various types. Such stresses may be the result the temperature changes during operation, or a gas pocket which may arise due to a partial blow-out. These stresses produce hollow spaces in the winding at which partial discharges can occur when no impregnation agent can penetrate into the hollow spaces to re-impregnate the polyproplylene foils. Moreover, a particular problem arises in connection with increased temperature, because the pressure in the winding can increase to such an extent that the foils or the paper tapes may rip, thereby destroying the capacitor.


Novel blends of algin, TKP and guar gum are disclosed. The blends are useful in commercial gum applications where thickening, suspending, emulsifying, stabilizing, film-forming, and gel-forming properties are needed. They are particularly useful in the paper industry.

Algin is a water-soluble polysaccharide found in all species of Phaeophyceae, brown algae. The generic term algin designates the derivatives of alginic acid chemically extracted from Phaeophyceae. The derivatives of alginic acid include varied soluble salts (e.g., sodium alginate) and salts of ethers (e.g., propylene glycol alginate); these derivatives, i.e., algin, are stored in their dry-powdered form. Algin is used in commercial gum applications for its thickening, suspending, emulsifying, stabilizing, adhesive, film-forming, and gel-forming properties.
Tamarind kernal powder is a commercially available product made by husking and milling the seed kernels of the tree Tamarindus indica Linn.
Guar gum is a commercially available product which is essentially the endosperm of the plant Cyanaposis tetragonolobus, family Leguminosae. Guar gum is used extensively as an additive in paper manufacturing as an aid in fiber-fiber bonding. Guar gum is also used as a flocculating agent in the mining industry since it flocculates clays, carbonates, hydroxides and silica.


Equipment-holder bar (10) associated with a rolling mill stand (11) for the positioning and successive clamping in position of at least a guide box (12) to guide rolled stock in relation to a specific rolling pass defined by rolling rolls (47), the bar (10) comprising a slider (18) able to move lengthwise in both directions on a stationary body (13) solidly fitted to a frame (15) of the rolling mill stand (11), the slider (18) being positioned lengthwise by positioner means (37) consisting of an outer sleeve (21) associated with a rotary positioner shaft (31) set in rotation by a suitable motor, the stationary body (13) and the slider (18) including reciprocal guide means (16-17), the stationary body (13) and the slider (18) comprising lower guide means (16a-17a) and downstream inclined guide means (16b-17b) and also upper movable guide means (38), the stationary body (13) including a lengthwise lodgement seat (22) for the positioner means (37) and a part (45) extending upstream of the seat (22) and containing an inclined surface (39) cooperating with the upper movable guide means (38), the slider (18) including a movable body (40) associated with fork means (19) and with the positioner means (37), the movable body (40) comprising an inclined surface (41) cooperating with the upper movable guide means (38), the upper movable guide means (38) being driven perpendicularly by a hydraulic actuator (35) so as to displace reciprocally and clamp the stationary body (13) and the slider (18).

This invention concerns an equipment-holder bar for a rolling mill stand.
The equipment-holder bar according to the invention is fitted advantageously to rolling mill stands so as to position correctly and to clamp in a desired position the equipment and particularly, but not only, a guide box fitted upstream and possibly also downstream of a rolling mill stand so as to guide the rolled stock.
This equipment-holder bar is installed in cooperation with the specific rolling pass defined by the rolling rolls.
The rolling mill stands of the state of the art entail a series of problems linked to the fact that they have to align and guide the rolled stock being fed so as to ensure the correct rolling of the rolled stock.
In particular, a guide box for the rolled stock is fitted for this purpose upstream of the rolling mill stand and has precisely the task of aligning and guiding the rolled stock immediately upstream of the specific rolling pass defined by the rolling rolls.
These guide boxes for the rolled stock can also be fitted downstream of the rolling mill stand. They entail the problem, however, that they have to be positioned first on the rolling mill stand and thereafter have to be clamped in that position so that they cannot be displaced.
In view of the present high rolling speeds the positioning has to be very accurate; at the present time these guide boxes for the rolled stock are installed on carriages able to run crosswise to the inlet of the rolling mill stand in one direction or the other.
These movable carriages are generally driven by a screw associated with a motor, which is actuated to achieve a millimetric alignment of the rolled stock in relation to the rolling pass.
These positioner carriages include clamping means, which are actuated when the guide box for the rolled stock has been aligned with the rolling pass.
This positioning and clamping system, however, has been found unsatisfactory inasmuch as the carriage undergoes very strong and continuous stresses during the passage of the rolled stock travelling at a high speed even greater than 100 meters per second.
Moreover, the rolled stock being fed, if it is not well aligned, damages the inlet of the guide box.
Furthermore, these stresses entail very strong vibrations and noises which create problems for the apparatus itself and for the surrounding environment.
Besides, owing to the high temperature of the rolled stock being fed, the guide box is cooled continuously with a great flow of water; this cooling water and the scale which becomes detached from the rolled stock passing through are deposited on the screw that adjusts and moves the movable carriage bearing the guide box, thus involving a set of problems due to wear, incorrect functioning, breakages, etc.
So as to obviate these problems, embodiments have been disclosed in which attempts have been made to stiffen the structure of the carriage bearing the guide box for the rolled stock and to reduce the infiltrations of water, scale and other debris into the inside of the carriage by closing the carriage at its upper and lower sides.

Equipment-holder bar for a rolling mill stand


An air flow direction adjusting device of an air-conditioning apparatus includes: a base member including attachment shafts; air flow direction adjusting members individually attached to the attachment shafts such that the air flow direction adjusting members are allowed to rotate; and a link plate configured to rotate the air flow direction adjusting members in an interlocked manner. At least one of the air flow direction adjusting members includes a rotation shaft attachment portion attached to the corresponding one of the attachment shafts, a link plate engagement portion to be engaged with the link plate, and an operation member attachment portion to which a manual operation member for manually adjusting orientation of the air flow direction adjusting members is attached. The manual operation member is not attached to at least one of the air flow direction adjusting members.

A known air flow direction adjusting device includes a plurality of air flow direction adjusting members disposed at an air outlet of an air-conditioning apparatus so as to change the direction of air flow blowing from the air outlet of the air-conditioning apparatus. For example, an air flow direction adjusting device of Patent Literature 1 includes an air flow direction adjusting member with a movable operation unit and an air flow direction adjusting member with no movable operation unit. Orientations of these air flow direction adjusting members are adjusted by operating the movable operation unit, and thereby, the direction of air blowing from the air outlet of the air-conditioning apparatus is adjusted.

Wind direction adjusting device of air-conditioning apparatus and air-conditioning apparatus


There is shown and described a bottle having an integral, retractable funnel at the top or opening thereof. The retractable funnel is disposed within the bottle in normal operation but is extended from the bottle opening during a refill operation.

1. Field of the Invention
This invention is directed to refillable bottles, in general, and to such bottles having integrally formed funnels associated with the openings thereof, in particular.
2. Prior Art
There are many known consumer utilizations of bottles which are refillable from other sources. For example, many cleaning solutions come in large containers for easy handling and storage. Smaller containers, e.g. bottles, are used in the every day use or application of the materials. For example, window cleaner or spray in the form of a liquid is stored in large containers having a size of a gallon or more. The ordinary applicator may contain a half pint or the like wherein the container is relatively easily handled by the user. Therefore, a large supply source is maintained for supplying the useful product but the actual applicator is maintained small for ready utilization.
When the applicator device is emptied, it is refilled from the storage container. However, in most cases the applicator bottle has a relatively small opening and/or neck at the top thereof. On the other hand, the storage container may have a much larger opening. Even if the storage container has an opening of substantially the same size and configuration as the applicator bottle opening, a significant chance of spillage occurs. In point of fact, spillage frequently occurs even though significant care and dexterity are exercised by the user. In the alternative, a funnel may be utilized in the refill operation. However, this has the disadvantage of requiring that a funnel be obtained or that the funnel have the appropriate size and configuration to accomodate both the refillable applicator bottle and the refill source container. The usual difficulties and problems which are encountered are well known to those in the art. In addition, where caustic chemicals are to be refilled, care must be given to thorough cleaning of the funnel prior to use.


A process and apparatus for fluidized catalytic cracking (FCC) with cooling of FCC catalyst during regeneration in a baffled heat exchanger attached to the regenerator. The heat exchanger has a vertical baffle defining an inlet and an outlet side. Lift gas added to the outlet side induces flow from the regenerator, around the baffle and back to the regenerator. A symmetrical design, with reversing flow can equalize wear on heat exchanger tubes and permit selected cooling if the heat exchanger outlet is near the regenerated catalyst outlet.

1. Field of the Invention
The invention relates to fluidized catalytic cracking and heat exchangers.
2. Description of Related Art
In the fluidized catalytic cracking (FCC) process, catalyst, having a particle size and color resembling table salt and pepper, circulates between a cracking reactor and a catalyst regenerator. In the reactor, hydrocarbon feed contacts a source of hot, regenerated catalyst. The hot catalyst vaporizes and cracks the feed at 425.degree. C.-600.degree. C., usually 460.degree. C.-560.degree. C. The cracking reaction deposits carbonaceous hydrocarbons or coke on the catalyst, thereby deactivating the catalyst. The cracked products are separated from the coked catalyst. The coked catalyst is stripped of volatiles, usually with steam, in a catalyst stripper and the stripped catalyst is then regenerated. The catalyst regenerator burns coke from the catalyst with oxygen containing gas, usually air. Decoking restores catalyst activity and simultaneously heats the catalyst to, e.g., 500.degree. C.-900.degree. C., usually 600.degree. C.-750.degree. C. This heated catalyst is recycled to the cracking reactor to crack more fresh feed. Flue gas formed by burning coke in the regenerator may be treated for removal of particulates and for conversion of carbon monoxide, after which the flue gas is normally discharged into the atmosphere.
Catalytic cracking has undergone progressive development since the 40s. The trend of development of the fluid catalytic cracking (FCC) process has been to all riser cracking and use of zeolite catalysts. A good overview of the importance of the FCC process, and its continuous advancement, is reported in Fluid Catalytic Cracking Report, Amos A. Avidan, Michael Edwards and Hartley Owen, as reported in the Jan. 8, 1990 edition of the Oil & Gas Journal.
Modern catalytic cracking units use active zeolite catalyst to crack the heavy hydrocarbon feed to lighter, more valuable products. Instead of dense bed cracking, with a hydrocarbon residence time of 20-60 seconds, less contact time is needed. Conversion of feed can now be achieved in less time and more selectively in a dilute phase, riser reactor.
Although reactor residence time has continued to decrease, the height of the reactors has not decreased proportionally. The need for a somewhat vertical design, to accommodate the great height of the riser reactor, and the need to have a unit which is compact, efficient, and has a small "footprint" has caused considerable evolution in the design of FCC units, which evolution is reported to a limited extent in the Jan. 8, 1990 Oil & Gas Journal article. One modern, compact FCC design is the Kellogg Ultra Orthoflow converter, Model F, which is shown in FIG. 1 of this patent application, and also shown as FIG. 17 of the Jan. 8, 1990 Oil & Gas Journal article discussed above. The unit uses a regenerator consisting of a bubbling dense bed of catalyst. The regenerator has an external heat exchanger, which allows the unit to process heavy crudes, or those containing large amounts of Conradson Carbon Residue material, without overheating.
Such cooling of the catalyst regenerator is ancient art. In the 40's, many FCC regenerators had external catalyst coolers. With better unit design, and more active catalyst, the units ran "heat balanced" and did not require catalyst coolers. Today FCC units are being pushed to crack heavier and heavier feeds, which contain large amounts of CCR, so once again catalyst coolers are needed to permit heat balanced operation.
Coolers are now usually connected to the bubbling dense bed of catalyst in the regenerator, as in the Kellogg HOC design. These bubbling dense beds regenerate catalyst and store it until recycled to the riser reactor. Not all regenerators use bubbling dense bed as the primary means of removing carbon from spent catalyst.
The "High Efficiency Regenerator" (H.E.R.) design uses a fast fluidized bed for most of the coke combustion, and a dilute phase transport riser for some CO combustion. Regenerated catalyst is collected in a bubbling dense bed for reuse, and for recycle to the coke combustor. Such a design makes more efficient use of the catalyst, in that the coke combustor is all highly active, unlike bubbling dense bed regenerators, which are troubled with stagnant beds (due to poor catalyst flow patterns) and regeneration gas bypassing (due to the formation of large bubbles within the bubbling dense bed). The H.E.R. design uses a turbulent fluidized bed, or a fast fluidized bed, which allows use of less catalyst than is required in a bubbling dense bed regeneration design.
H.E.R. units have, like bubbling bed units, been pushed to deal with the increased carbon burning duties associated with cracking heavy crudes. The operation of these units has been modified to try to maintain heat balanced operation, either by limiting the heat release during regeneration (partial CO combustion mode) or by removing heat via heat exchange.
A partial combustion route to limiting heat release is disclosed in U.S. Pat. No. 4,849,091, which is incorporated herein by reference. Such an approach allows some of the heat release to be shifted to a downstream CO boiler. This takes some of the load from the regenerator, but is not an option at some refineries, or does not take enough heat from the regenerator. Thus many regenerators now run too hot, and some type of heat exchange is needed.
Adding heat exchangers to both bubbling bed and H.E.R. regenerators is reported in many patents.
In U.S. Pat. No. 4,439,533, incorporated by reference, a backmixed heat exchanger is added to the bubbling dense bed of catalyst. There are no slide valves, or elaborate catalyst supply and return lines to the heat exchanger, rather the heat exchanger is closely coupled, and in open fluid communication with the bubbling dense bed. The backmixed heat exchanger looks something like a thimble. Adjusting the amount of gas added to the "thimble" containing the heat exchange tubes allows some control of catalyst circulation and of heat exchange. Cooling fluid, usually water, passes through a tube bundle in the thimble. Cooled catalyst returns to the bubbling dense bed regenerator using the same opening as the entering catalyst.
In U.S. Pat. No. 4,434,245, incorporated by reference, a flow through heat exchanger is disclosed for use with a high efficiency regenerator. There is a hot catalyst inlet in the bubbling dense bed, and a cooled catalyst outlet in the coke combustor or FFB region. This approach requires a significant amount of hardware modifications, slide valves, and a fluidizing air outlet from the upper portion of the heat exchanger to the dilute phase region above the bubbling dense bed.
In U.S. Pat. No. 4,578,366 a flow through heat exchanger is used. Fluidizing gas in the heat exchanger supports combustion in the coke combustor. Catalyst slide valves regulate the flow of hot regenerated catalyst from the dense bed to the heat exchanger.
In U.S. Pat. No. 4,595,567 a flow through heat exchanger is used with heat pipes. Catalyst slide valves regulate the flow of hot regenerated catalyst from the bubbling dense bed into the heat exchanger.
In U.S. Pat. No. 4,430,302 a fast fluidized bed regenerator (without catalyst recycle) has looped heat exchange coils in the fast fluidized bed. Looped coils, formed from 11/2 or 2" 304H stainless steel were suspended in multiple banks in the bed. Such an approach will remove a lot of heat, but requires a lot of custom work and is hard to control. To avoid thermal shock refiners like to have heat exchange fluid flowing all the time through the tubes. Heat removal goes on all the time, even during startup when heat input rather heat removal is needed.
I reviewed this extensive art on coolers in regenerators but found nothing that was completely satisfactory. They either cost too much, or removed too little or too much heat, and/or were hard to control.
The flow through, dense phase, down flow exchanger is efficient in terms of heat removal and controllability, but requires separate catalyst inlets and returns, slide valves, and a lot of space. Capital costs are fairly high.
The dense phase back-mixed exchanger avoids some of the plumbing costs. It has only a single connection to the regenerator for solids entry and exit. This reduces the cost to install it, and reduces efficiency to about 60% of a flow through exchanger. The same opening is used for solids entry and exit, and the traffic jam restricts catalyst traffic.
I wanted to avoid use of slide valves to control catalyst flow to the regenerator. These can cost more than $1,000,000 each and are usually used in pairs to permit servicing.
I wanted to avoid coils within the regenerator. Cooling coils should always be full of coolant (to avoid thermal shock and damage to the tubes). Coils full of coolant remove heat even during startup, when the unit requires heating, not cooling. There is concern too that coils may interfere with fluidization within the regenerator.
I wanted a reliable and efficient way to remove heat from a regenerator during normal operation, which could be isolated during startup, while achieving efficient heat removal during normal operation. It was my goal to retain the mechanical simplicity and low cost of a backmixed, dense phase heat exchanger, but improve its efficiency to something approaching that of a flow through heat exchanger.
A baffling improvement provided the key to obtaining the performance of a flow through exchanger in a backmixed exchanger. Using a baffle also allowed frequent or periodic reversal of flow patterns through the regenerator, which can extend the life of the heat exchanger tubes. With proper design, I was also able to selectively cool either the catalyst which would be returned to the reactor, or the bulk of the catalyst in the regenerator.

FCC process and apparatus for cooling FCC catalyst during regeneration


A linear electrodynamic machine is disclosed having non-axisymmetric, interdigitating interfaces between moving and fixed magnetic circuit elements. The moving magnet elements may be of permanent magnet or electromagnetic construction, and in one embodiment constitute low reluctance elements moving relative to fixed energizing and output coils. Magnetic elements on a reciprocating plunger couple to fixed elements of a magnetic circuit in an interdigitating manner. Alternators and motors with non-axisymmetric, interdigitating interfaces are disclosed.

1. Field Of The Invention
The present invention relates to linearly reciprocating electrodynamic motors and alternators, and more particularly to linearly reciprocating electrodynamic motors and alternators having non-axisymmetric, interdigitating interfaces between moving and fixed magnetic circuit elements.
2. Description of the Prior Art
It is known in the art that moving flux fields in proximity to iron laminations surrounded by conductive coils will induce an electric field in, and corresponding voltage across, the conductive coils as a result of flux variations within the laminations, such as occurs in what are commonly known as alternators. Similarly, it is known that varying electrical current in conducting coils can be used to produce varying flux fields that are in turn used to produce mechanical movement (such as rotation or linear motion) of an appropriate magnetic member in proximity to the varying flux fields, such as occurs in what are commonly known as motors.
Alternators and motors in which the principal motion is along a single axis or line often are referred to as "linear" alternators and motors. Various applications for such linear alternators and motors are known in the art.
One application for a linear alternator is to be coupled to the piston of a Stirling engine. It is known to provide for hermetic sealing of high-pressure Stirling engines by incorporating a power conversion device, such as a linear electric alternator driven by the engine piston, within the pressure vessel. Such linear alternators are directly actuated by the reciprocation of the piston in order to avoid any intermediate linkages and the attendant need for lubrication, since lubricants typically must not be used within the pressure vessel of a Stirling engine.
In the past, such linear alternators have been constructed in substantially axisymmetric form, such that their operation was independent of the angular position of the plunger. This has been required with the commonly-used fluid-film, typically gas, bearings between the reciprocating plunger/piston and fixed supports. Such bearings require extremely close clearance fits, which are difficult in any shape, but are most readily achieved in circular form. Such axisymmetry to the piston/plunger typically precludes any non-sliding connections, it being unrestrained except to one axis and thereby allowing movement such as rotation. Sliding contacts are to be avoided in most applications for such machines in that rubbing surfaces would tend to prematurely wear out, and the desired long service life would not be achieved.
Electrically, this tends to constrain the moving magnetic flux generators on the plunger to be constructed of permanent magnets, typically in the form of annular rings or the like, requiring no electrical energization to create the moving magnetic flux fields. In such prior machines, the plunger typically must be round in section, and as a result permanent magnets must be specially shaped to fit such circular shape. In addition, for a given stroke and magnetic strength, the perimeter of the magnet ring usually is the limiting feature dimension for determining output power, forcing machines of large power output to be large in diameter, to the detriment of mass and structural rigidity.
With reference to FIG. 1, a typical permanent magnet linear alternator/motor machine of conventional design will be described.
As shown in the cross-sectional view of FIG. 1, all components are substantially axisymmetric around the indicated center axis. Four rings of permanent magnet material 1a and 1b are axially arrayed in cylindrical plunger assembly 8. Plunger assembly 8 comprises magnet rings 1a, and 1b, spacer ring(s) 2 of material with low magnetic permeability, and piston 7. Magnet rings 1a and 1b are spaced in axially-adjacent pairs of opposite magnetic polarity as illustrated, and the axial extent of each ring is substantially equal to the reciprocation stroke of plunger assembly 8. At the mid-stroke position of plunger assembly 8, the magnet ring pairs 1a and 1b are centered in gaps in a toroidal flux path defined by inner and outer radial magnetically-permeable lamination plates 4' and 4, respectively. A coil of electrically-conductive wire 5 is wound inside magnetically-permeable plates 4 that comprise part of the toroidal flux circuit. Plunger assembly 8 is supported and positioned for reciprocation by a sliding bearing 9 in support frame 6.
In operation, plunger assembly 8 moves alternately to either end of its stroke, bringing alternately the upper and lower members of each magnet ring pair 1a/1b into alignment with the gap in the toroidal, magnetically-permeable path defined by inner and outer radial lamination plates 4' and 4. Coil 5 thus is alternately surrounded (and linked with) a reversing magnetic flux in lamination plates 4' and 4. This flux induces alternating voltage in coil 5 according to known electromagnetic principles. When an electrical load is attached to the ends of coil 5, a current is enabled to flow, producing power.
Alternatively, an alternating electric current can be passed through coil 5, inducing a reversing magnetic flux in laminations 4 and 4', thereby causing plunger magnet rings 1a/1b to align alternately with the lamination flux direction. Since axially adjacent magnet rings 1a and 1b are of opposite polarity, reciprocation of plunger assembly 8 results as rings la having polarity which reinforces the flux in laminations 4 and 4' alternately align and then are expelled in favor of opposite-polarity rings 1b when the electrically-induced flux reverses, and vice versa.
The end result of such prior art machines is, however, that, in the case of an alternator, the alternator and its bearings typically constitute more than half the size and weight, and up to half the cost of a Stirling engine and linear alternator assembly. Similar disadvantages result when such prior machines are configured to be operative as a linear motor.

Clever Fellows Innovation Consortium, Inc.


This invention relates to an improved automatic document feeder which may be used, for example, on an image forming apparatus. The apparatus in accordance with the invention includes a final document detecting circuit which detects whether a document sent from an original setting device onto an original mounting device is the final document of a set. A normal end detecting device detects whether all of the image forming steps have been completed normally as to the final document of the set. A controlling device moves the final document to be discharged outside of the automatic document feeder after all of the image forming steps have been finished normally on the final document. The controlling device is activated based on signals from the final document detecting device and the normal end detecting device. The control circuit allows documents other than the final document to be moved outside of the image forming device before all of the image forming steps have been completed normally.

1. Field of the Invention
The present invention relates to an automatic document feeder used in a copier or other image forming apparatus for feeding documents automatically.
2. Description of the Related Art
Hitherto, for example, in a copier, instead of having an operator place the documents one by one on the original platen glass, an automatic document feeder (ADF) is known for feeding the documents automatically onto the original platen glass. The known ADF is used by having the operator set the documents on the original tray, automatically feeding the documents one by one to the platen glass, executing copying by scanning each document with the optical system, and then sending out the documents automatically from above the original platen glass.
In such ADFs, a high speed mode can be selected in certain models. That is, after feeding the documents onto the original platen glass as mentioned above, the optical system scans the original from the home position and moves to the rear end of the original, and then returns to the home position. In this process, in order to copy as quickly as possible, high speed copying is realized by sending out the original when the optical system has finished scanning, without waiting until the optical system returns to the home position.
This document feeding timing for high speed operation is also the same for the final document.
However, when the final document is immediately discharged outside right after scanning, as described above, there may be a jamming, for example, while the paper on which the image has been transferred is being conveyed to the thermal fixing unit.
In such a case, the final document, once discharged outside, must be put back onto the original platen glass by the operator. This procedure is not only troublesome, but may involve the risk of returning a wrong document to the platen glass.

Automatic document feeder for feeding documents based on signals from a final document detecting device and a normal end detecting device


An airfoil configured for low speed performance in an unmanned aerial vehicle includes an upper surface having an upper surface portion with a top local surface angle magnitude of less than 5 degrees at a subsection of a chord and a lower surface having a lower surface portion with a bottom local surface angle magnitude of less than 5 degrees at the subsection of the chord. The chord is defined by a line starting at a leading edge of the airfoil and extending to a trailing edge of the airfoil.

Some aircraft designs, particularly unmanned aerial vehicles, use complex wing or airfoil shapes for improved low-speed performance. These airfoils often exhibit severe stall properties that prevent the aircraft from operating over a full range of conditions. Further, these complex shapes are difficult to manufacture, have limited internal volume, and may not be conducive to attaching external components, such as trailing edge flaps.
A side view of a prior art airfoil 10 is illustrated in FIG. 1. The airfoil 10 has an upper surface 12 and a lower surface 14. In order to achieve good performance at low airspeeds, the airfoil 10 is characterized by a complex curvature that increases both structural weight and manufacturing complexity. The thin trailing edge 16 makes it difficult or impossible to integrate trailing edge flaps. The thin profile and high camber reduces interior volume and correspondingly reduces fuel storage capacity. The high camber also increases the difficulty of including the structural components necessary for integrating a deployable (folding) wing into an airframe.

Low speed airfoil design for aerodynamic improved performance of UAVs