The invention is a method for producing reservoir fluids from an underground reservoir through the wellbore. The method includes the steps of intaking the gas phase from the wellbore into the wellbore-contained pump drive, powering the pump drive using the gas pressure of the gas phase in the wellbore, pumping the liquid phase from the wellbore towards the surface by a first pump and exhausting the gas phase from the pump drive towards the surface.

The removal of liquids which accumulate in producing wells is required in order to enhance production from the well and the overall operation of the production system. In particular, liquids removal is necessary for the dewatering of gas wells and the removal of oil from wells where mixed oil and gas exists in the underground reservoir. If the liquids, such as water and/or oil, are not removed, the liquids tend to accumulate and fill or load up the well, which restricts the flow of the gas to the surface. Eventually, the liquids will choke off gas production completely. Therefore, the problem to be overcome is to remove the liquids continually to avoid their accumulation in the well.
One approach to this problem is to use a gas lift system which uses the natural gas pressure in the reservoir to lift the liquids from the well. In a gas lift system, a tubing string is typically located in the well which extends from the surface into the accumulated liquids such that the accumulated liquids may flow into the tubing string. The gas then enters the tubing string from the underground reservoir at chosen intervals along the tubing string to cause the liquids within the tubing string to rise to the surface. A freely moveable plunger or pig may be located in the tubing string to minimize the penetration of the gas through the liquids. Where the gas lift system uses the pressurized gas from the reservoir to transport slugs of the liquid to the surface, a small diameter tubing string for producing the liquids is often required so that the gas pressure and the gas velocity are sufficient to carry the liquids to the surface. However, the requirement for small diameter tubing may significantly restrict the flow of the liquids and reduce the gas production. As well, the gas and the liquids are typically well mixed at the surface, which may cause problems in surface production lines, such as hydrate formation or freezing. Further, gas lift systems have been found to be unsuitable where the downhole gas pressure or the gas velocity is low and thus, the gas is unable to overcome the pressure head of the liquids to carry the liquids to the surface.
Further gas lift systems have been designed which only periodically or intermittently lift the liquids to the surface in a cyclical operation in order to allow the natural gas pressure to develop in the well between the cycles to a critical level necessary to lift the liquids. Examples of such systems include U.S. Pat. No. 2,136,229 issued May 16, 1938 to Baldwin et al, U.S. Pat. No. 4,596,516 issued Jun. 24, 1986 to Scott et al and U.S. Pat. No. 4,465,435 issued Aug. 14, 1984 to Copas. Some of these systems use a timer operated valve, located in the outlet of the tubing containing the liquids. The valve is set to periodically open at a timed interval equal to the time required for the natural gas pressure in the well to recover following the release of such pressure. Other systems use valves sensitive to a predetermined differential pressure between the liquids in the tubing string and the gas to control the periodic opening of the valve to allow lifting of the liquids by the gas.
Other gas lift systems introduce pressurized gas into the well from an outside source in addition to the natural gas from the reservoir, as shown in U.S. Pat. No. 2,132,738 issued Oct. 11, 1938 to Knox. However, the introduction of the pressurized gas into the well to lift the liquids requires the use of a compressor which tends to increase both the cost and complexity of the production apparatus required.
A further approach to the problem of liquid loading is shown in Canadian Patent No. 1,167,760 issued May 22, 1984 to Prather which describes a reciprocating surface pump which is powered by the natural gas pressure from the reservoir. The reciprocating surface pump is connected to a string of sucker rods which are connected to a conventional downhole pump. In essence, the gas from the well is conducted to the surface where is drives the reciprocating surface pump. The reciprocating pump then powers the downhole pump, which pumps the liquids to the surface. Several disadvantages are exhibited by this system. First, the system requires a reciprocating pump at the surface. Second, as the gas is conducted to the surface for powering the reciprocating pump, the reciprocating pump must be designed as a pressure vessel able to withstand the pressure differential between the atmosphere and the downhole pressure. As well, there may be some energy loss as the gas travels from the bottom of the well to the reciprocating surface pump. Third, reciprocation of the sucker rods within the tubing string results in wearing of the tubing string and energy loss due to friction between the sucker rods and the tubing string.
There is therefore a need in the industry for an improved apparatus and method for producing liquids contained in an underground reservoir through a wellbore, which apparatus is powered by the pressure of the gas naturally contained within the reservoir. Further, there is a need for the apparatus to be contained downhole when in operation such that the apparatus creates a mechanical advantage for pumping the liquids towards the surface.

Method for underground-reservoir fluids production with pump drive contained within the wellbore


In a programmable power supply used in a semiconductor test apparatus, high-speed switching of a large current in a current rage or an output relay is enabled. In a MOSFET drive circuit 22 of a switch portion 20 provided in a programmable power supply 10 of a semiconductor test apparatus 1, a capacitor portion 22-12 is charged with electric charges by a current from a light receiving portion 22-12 of a light insulating element 22-1. When an SWA is turned on (SWB is turned off) by changeover of the analog switch portion 22-3, a gate of each MOSFET in the MOSFET portion 21 is charged with the electric charges stored in the capacitor portion 22-12, and enters an ON state. On the other hand, when the SWB of the analog switch portion 22-3 is turned on (SWA is turned off), the gate of the MOSFET is discharged.

1. Field of the Invention
The present invention relates to a MOSFET (Metal Oxide Semiconductor FET (Field Effect Transistor)) drive circuit which drives a MOSFET, a programmable power supply and a semiconductor test apparatus which include this MOSFET drive circuit, and more particularly, the present invention relates to a MOSFET drive circuit which can realize high-speed switching of the MOSFET, a programmable power supply and a semiconductor test apparatus.
2. Description of the Related Art
A programmable power supply used in a semiconductor test apparatus includes a function to measure an electric current consumption of a DUT (Device Under Test) by applying a voltage to the DUT (voltage application current measurement function), a function to measure an output voltage of the DUT by flowing a current in the DUT (current supply voltage measurement function) or the like.
Such a programmable power supply can generally supply a current up to approximately 1 A, but a power supply current of a DUT varies depending on each product class and is as very wide as several-μA to 1 A. Therefore, for example, when measuring a power supply current of a DUT by using the voltage application current measurement function, a measurement range in the programmable power supply must be switched in accordance with a standard value of the power supply current of the DUT as a measurement target in order to increase the accuracy of a measurement result.
FIG. 6 shows a circuit configuration of this conventional programmable power supply.
As shown in the drawing, a programmable power supply 10 of a semiconductor test apparatus 1 includes a DA converter 11, resistors R12 and R13, a differential power amplifier 14, a buffer amplifier 15, a small-current measurement portion 16, and a large-current measurement portion 17 as main structures.
Here, the large-current measurement portion 17 is a part which measures a large current in power supply currents of a DUT 30, and has current detection resistors R17-11 to R17-1n, a potential difference detector 17-2, an AD converter 17-3 and a switch portion 20.
Of these members, the resistor R17-11 is a resistor which constantly flows there through a power supply current, and the resistors R17-12 to 17-1n are flow dividing resistors which enlarge a measurement range. These resistors R17-1 to 17-1n can use the same low resistance value Ra.
The switch portion 20 is a part which performs switching so as to supply a current to the flow dividing resistors R17-12 to R17-1n corresponding to a range which is set at the time of current measurement and, on the other hand, so as not to supply a current to the flow dividing resistors R-12 to R17-1n which do not correspond to this range. As shown in FIG. 7, the switch portion 20 has a MOSFET portion 21 and a MOSFET drive circuit 100.
The MOSFET portion 21 has a structure in which two MOSFETs form a pair. The number of the provided MOSFET portions 21 is the same as that of the flow dividing resistors R17-12 to R17-1n, and a flow dividing branch circuit is constituted by a combination of one flow dividing resistor R17 and the MOSFET portion 21 which determines whether a current is caused to flow through this resistor. Further, the plurality of flow dividing branch circuits are provided and connected with each other in parallel, thereby constituting a flow dividing circuit.
The MOSFET drive circuit 100 is a circuit which drives each MOSFET provided in the MOSFET portion 21, and has a light emitting element 110, a photodiode 120 and an optical MOS 130.
The light emitting element 110 emits light beams upon receiving an input signal from an input side.
The photodiode 120 charges a gate of the MOSFET of the MOSFET portion 21 upon receiving the light beams from the light emitting element 110. As a result, a current is caused to flow through the resistor R17 connected to that charged MOSFET, and a current based on a corresponding range can be measured.
The optical MOS 130 discharges the gate of the MOSFET of the MOSFET portion upon receiving the light beams from the light emitting element 110. As a result, a current is prevented from flowing through the resistor R17 connected to that discharged MOSFET.
It is to be noted that electrical insulation is achieved between the light emitting element 110 and the photodiode 120 and between the light emitting element 110 and the optical MOS 130.
Furthermore, FIG. 8 shows a relationship between a signal (input signal) from the input side of the switch portion 20 and a state of the MOSFET (ON state/OFF state).
First, when the input signal is inputted, the photodiode 120 is turned on, and the optical MOSFET 130 is turned off. As a result, the gate of the MOSFET of the MOSFET portion 21 is charged and turned on.
On the other hand, when the input signal is not inputted, the photodiode 120 is turned off, and the optical MOS 130 is turned on. As a result, the gate of the MOSFET of the MOSFET portion 21 is discharged and turned off.
By switching the signal to be inputted to the input side of the switch portion 20 in this manner, ON/OFF of the MOSFET of the MOSFET portion 21 can be changed over. As a result, a current flows through the flow dividing resistors R17-12 to R17-1n connected to the MOSFET which have entered the ON state, and a current can be measured in a range corresponding to these flow dividing resistors R17-12 to R17-1n (see, e.g., patent reference 1: Japanese Patent Application Laid-open No. 11-006860).
However, in the above-described conventional programmable power supply, a time until charging the gate of the MOSFET is completed after the input signal is inputted or a response time until discharging starts after no input signal is inputted requires a considerable time.
For example, although an output current of the photodiode is used to charge the gate of the MOSFET, since this output current is relatively small, a considerable time is required until charging the MOSFET is completed ("t1" in FIG. 8).
On the other hand, although discharging the gate of the MOSFET is performed by using the optical MOS, discharging the gate of the MOSFET cannot be started before the optical MOS is charged, and hence start of discharging of the MOSFET is delayed for a time which is required to charge the optical MOS ("t2" in FIG. 8).
Specifically, the time until charging the gate of the MOSFET is completed after the input signal is inputted (t1) or the response time until discharging starts after no input signal is inputted (t2) is approximately several-ten μs to several ms.
Such a situation means that switching ON/OFF of the MOSFET is not rapidly carried out, and leads to a problem that a large current cannot be rapidly switched in a current range or an output relay in the programmable power supply or the semiconductor test apparatus.
Thus, as a solution to this problem, connecting many photodiodes can be considered.
According to this solution, since the output current is increased, a charge time of the gate of the MOSFET can be assuredly reduced.
However, connecting the photodiodes as many as the charge time can be greatly reduced increases a circuit area. Therefore, there occurs a new problem that this solution cannot contribute to a reduction in size of the programmable power supply or the like.

MOSFET drive circuit, programmable power supply and semiconductor test apparatus


A package-on-package (POP) package in which semiconductor packages are stacked using lead lines rather than conventional solder balls, and a fabricating method thereof are provided. According to the POP package and the fabricating method thereof of the present invention, the POP package is prevented from being short-circuited even when an underlying semiconductor package gets thicker and the POP package can sufficiently withstand deformation caused by post-fabrication warpage.

1. Technical Field
The present invention relates to a package-on-package (POP) package and a fabricating method thereof, and more particularly, to a POP package which is prevented from being short-circuited even when an underlying semiconductor package is thick and which can sufficiently withstand deformation caused by post-fabrication warpage, and a fabricating method thereof.
2. Description of the Related Art
In recent years, as electronic products have been incorporating greater functionality, a number of devices need to be integrated in one substrate, which makes it difficult to achieve the desired compactness of the products. Accordingly, researchers are currently seeking a technique of integrating a number of devices in a limited space.
Mounting several chips in one semiconductor package is well known. Furthermore, a package-on-package (POP) package is well known in which a package is formed on another package.
A conventional POP package will be described with reference to FIG. 15.
A first semiconductor package 10 includes a first substrate 11 with a semiconductor chip (not shown) mounted thereon, a mold 14 for holding the semiconductor chip, and external contact electrodes 12 and solder balls 13 for connection to an external board.
A second semiconductor package 20 includes a second substrate 21 and a semiconductor chip (not shown) mounted thereon, a mold 24 for holding the semiconductor chip, and external contact electrodes 22 and solder balls 23 for connection to the underlying first semiconductor package 10.
The second semiconductor package 20 is stacked on the first semiconductor package 10 and connected thereto through the solder balls 23.
In the case where the first semiconductor package 10 is a multi-chip package (MCP) in which several semiconductor chips are stacked, in accordance with a recent trend, the mold 14 is thick and thus the solder balls connecting the first semiconductor package 10 to the second semiconductor package 20 should be large. Recently, as electronic products get more compact, packages get smaller, making it difficult to secure a sufficient interval between the solder balls. In other words, as the solder balls become larger to accommodate the height of the mold in the lower package, it is difficult to achieve sufficient spacing between the solder balls to prevent shorts between them.
As a result, there is a problem in that the solder balls are short-circuited, as shown in FIG. 16B. That is, the solder balls are desired to be evenly arranged as shown in FIG. 16A, but instead, they are lumped and short-circuited as shown in FIG. 16B.
In addition, a connection between stacked packages using solder balls causes the following problems: A fabricated POP package may be bent due to, for example, hardening or heating as time lapses and, in this case, a difference in warpage between the stacked semiconductor packages may cause disconnection between the packages, as shown in FIGS. 17A and 17B.
Accordingly, there is a need for a method for connection in a POP package which is capable of preventing short-circuits due to compactness of products and allowing a semiconductor package to sufficiently withstand deformation caused by post-fabrication warpage.

POP package and method of fabricating the same


The present invention relates to therapeutic ADCs comprising a drug attached to an anti-cancer antibody or antigen-binding antibody fragment. Preferably the drug is SN-38. More preferably the antibody or fragment thereof binds to Trop-2 and the therapy is used to treat a Trop-2 positive cancer. Most preferably the antibody is hRS7. The ADC is administered to a subject with a cancer in combination with an ABCG2 inhibitor. The combination therapy is effective to treat cancers that are resistant to drug alone and/or to ADC alone.

Resistance of cancer cells to chemotherapy has been a major treatment difficulty for decades and results in approximately 90% of cancer treatment failures (Pluchino et al., 2012, Drug Resistance Updates 15: 98-105). Certain cancers exhibit intrinsic resistance to chemotherapeutic agents, while in others drug resistance develops during the course of therapy (Lippert et al., 2011, Int J Med Sci 8: 245-253; Ricci et al., 2015, J Develop Drugs 4:138). Multiple drug resistance (MDR) is one of the most common ways in which cancer cells develop resistance to chemotherapeutic agents, primarily due to the active drug efflux catalyzed by ATP binding cassette (ABC) transporters (Ricci et al., 2015, J Develop Drugs 4:138). While the ABC transporters comprise a very large superfamily with varied functions, only a few of these transporters appear to be involved in MDR, including ABCB1, ABCC1 and ABCG2 (Ricci et al., 2015, J Develop Drugs 4:138). Of these, the ABCG2 transporter is the predominant one expressed in solid tumors (Ricci et al., 2015, J Develop Drugs 4:138).
While chemotherapy with systemic drug administration has been widely used in cancer treatment, more recently the targeted delivery of drugs in the form of antibody-drug conjugates has improved efficacy and safety of anti-cancer agents. Such ADCs provide targeted delivery of the conjugated drug to cells expressing disease-associated antigens, such as tumor associated antigens (TAAs), while reducing systemic exposure of normal tissues that have lower expression levels or do not express the targeted antigen. Typically, the drug conjugate is released intracellularly after internalization of the ADC, although in some cases extracellular release from the cell-bound ADC may also occur. In either case, tumors may still exhibit intrinsic or developed resistant to the anti-cancer agent, due to the activity of ABC transporters. Thus, despite the notable success in treating diverse cancers, chemotherapeutics, including antibody-drug conjugates (ADCs), lose clinical activity over time, as exemplified by irinotecan (Xu et al, 2002, Ann Oncol 13:1841-51), doxorubicin (Miller et al., 1988, J Clin Oncol 6:880-8), paclitaxel (Orr et al., 2003, Oncogene 22:7280-95), cisplatin (Siddik, 2003, Oncogene 22:7265-79), gemtuzumab ozogamicin (Walter et al., 2007, Blood 109:4168-70), inotuzumab ozogamicin (Takeshita et al., 2009, Br J Haematol 146-34-43), and others (Szakacs et al., 2006, Nat Rev Drug Discov 5:219-34).
The occurrence of drug resistance in cancer cells can result from a variety of factors (Housman et al., 2014, Cancers 6:1769-92), such as decreased uptake of soluble drugs, activation of drug-detoxifying systems, modulation or mutation of drug targets, defective apoptosis pathways, and above all, over-expression of one or more efflux pumps of the ATP-binding cassette (ABC) superfamily (Gottesman et al., 2002, Nat Rev Cancer 2:48-58). The human genome comprises a total of 49 genes in the ABC superfamily (Vasiliou et al., 2009, Hum Genom 3:281-90), each assigned to one of seven subfamilies (A through G) based on the order and sequence homology of the transmembrane (TM) domain and the nucleotide-binding folds (NBFs). To date, ABCB1 (also known as MDR1 or P-gp), ABCC1 (also known as MRP1), and ABCG2 (also known as BCRP, MXR, or ABC-P), account for most studies on MDR (Ambudkar et al., 2003, Oncogene 22:7468-85; Cole, 2014, J Biol Chem 289:30880-8; Doyle and Ross, 2003, Oncogene 22:7340-58).
Members of the ABC superfamily are transmembrane proteins, expressed either as a full- or half-transporter. A full-transporter typically contains two transmembrane (TM) domains and two nucleotide-binding folds (NBFs), with the TM domains participating in substrate recognition and translocation across the membrane, while the cytosolic NBFs provide the driving force for transport via hydrolysis of the bound ATP. By contrast, a half-transporter has only one TM domain and one NBF, and must form either homodimers or heterodimers to be functional. A notable example of a full-transporter is ABCB1, whose substrates include vinca alkaloids, anthracyclines, epipodophyllotoxins, taxanes, irinotecan, and SN-38 (Szakacs et al., 2006, Nat Rev Drug Discov 5:219-34). The five members of the ABCG subfamily are all half-transporters (Vasiliou et al., 2009, Hum Genom 3:281-90), of which ABCG2 has been identified for its role in mediating cellular resistance to SN-38 (Brangi et al., 1999, Cancer Res 59:5938-46; Kawabata et al., 2001, Biochem Biophys Res Commun 280:1216-23), as well as to tyrosine kinase inhibitors (Ozvegy-Laczka et al., 2005, Drug Resist Updat 8:15-26).
With the molecular mechanisms of intrinsic and acquired drug resistance in cancer increasingly being delineated, multiple approaches to circumvent MDR have emerged. For example, the sensitivity of inotuzumab ozogamicin in ABCB1-expressing sublines of Daudi and Raji lymphomas could be restored effectively with PSC-833 (Walter et al., 2007, Blood 109:4168-70), a second-generation modifier of ABCB1 (Twentyman and Bleehan, 1991, Eur J Cancer 27:1639-42). The use of a hydrophilic linker for conjugating DM1 to antibodies also enabled such ADCs to evade ABCB1-mediated resistance (Kovton et al., 2010, Cancer Res 70:2528-37), presumably due to the generation of a cytotoxic metabolite that was better retained by the ABCB1-expressing cells. In addition, targeting detoxifying enzymes, such as glutathione S-transferase, with intracellularly activated prodrugs was found to be promising (Ramsay and Dilda, 2014, Front Pharmacol 5:181). However, the rationale of using inhibitors of ABC transporters to overcome MDR has met little success in clinical trials, which could be in part due to both imperfect inhibitors and inadequate study design. This is being addressed by developing newer agents with greater substrate specificity, higher potency, lower toxicity, and improved pharmacokinetic properties.
Sacituzumab govitecan, hereafter referred to as IMMU-132, is a Trop-2-targeting ADC of SN-38, the active metabolite of irinotecan. IMMU-132 departs from most ADCs in its use of a moderately, not ultratoxic drug, its high drug to antibody ratio (DAR) without impairing target affinity and pharmacokinetics, and its selection of a pH-sensitive, cleavable linker to confer cytotoxicity to both tumor and bystander cells (Cardillo et al., 2011, Clin Cancer Res 17:3157-69; Cardillo et al., 2015, Bioconjugate Chem 26:919-31; Goldenberg et al., 2015, Oncotarget 6:22496-512). This novel ADC is currently in clinical trials for patients with advanced triple-negative breast cancer (Starodub et al., 2015, Clin Cancer Res 21:3870-8), urothelial bladder cancer (Faltas et al., 2016, Clin Genitourinary Cancer 14:e75-9) and other solid cancers. Since these patients were all heavily pretreated with chemotherapy, the presence of acquired resistance with the expression of MDR genes is highly likely, which may affect the therapeutic outcome of IMMU-132. A need exists for improved methods of use of ADCs, such as IMMU-132, to treat tumors that are resistant to chemotherapy.

This patent is subject to a terminal disclaimer.

Combination of ABCG2 inhibitors with sacituzumab govitecan (IMMU-132) overcomes resistance to SN-38 in Trop-2 expressing cancers


A camera has a lens mount for mounting an interchangeable lens unit. The camera further includes a casing, a chassis provided in the interior of the casing, a button provided to the casing, a lock mechanism (actuated in response to the button) which locks the lens unit in a state the lens unit is mounted on the lens mount, a sensor unit which detects whether the lock mechanism locks the lens unit or not. The sensor unit is disposed in a space provided to the chassis. The camera is provided with an actuator moved in response to the lock mechanism, which penetrates a panel of the chassis so that the actuator can actuate the sensor unit.

The present invention relates to a camera having a lens mount for mounting an interchangeable lens unit.
Generally, a camera (for example, a single reflex lens camera) has a lens mount for mounting an interchangeable lens unit. The lens mount and the lens unit respectively include a mount ring and a joint ring, which are mating with each other.
In order to transmit auto-exposure (AE) signals and auto-focus (AF) signals between the lens unit and a controller provided in a body of the camera, the mount ring is provided with several connector pins, while the joint ring is provided with several receptacles which receive the connector pins. The connector pins are arranged in a circumference (on the mounting ring) with certain intervals. When the lens unit is mounted to the lens mount, the connector pins and receptacles are electrically connected.
Recently, a driving motor (for example, a focusing motor or a zooming motor) is provided to the lens unit. Thus, it is necessary to provide additional connector pins and receptacles used for supplying power to the lens unit.
In order to minimize a space for the connector pins, it is preferred to arrange the connector pins for signal transmission and the connector pins for power supply on a same circumference. However, when a user rotates the lens unit to remove the lens unit from the lens mount, there is a possibility that the connector pins for power supply is unintentionally contact with the receptacles for signal transmission. In such case, power is unintentionally supplied to a circuit in the lens unit (via receptacles for signal transmission), which may damage the circuit.
In order to solve this problem, a recently developed camera is arranged to turn off the power supply when the lens unit is not mounted. In order to detect whether the lens unit is mounted to the lens mount or not, such camera has a sensor provided to a so-called lock-release-button. The button is arranged to release the lock of a lock mechanism (which locks the lens unit mounted to the lens mount) and is pressed while the user removes the lens unit from the lens mount.
However, since the button is generally provided to a front wall of a casing of the camera, the sensor is also located behind the front wall of the casing. Accordingly, if water penetrates into the casing of the camera (through a gap around the button), the sensor may get wet. Thus, there is a possibility that electric parts of the sensor get rusty, causing a faulty continuity.


A bow sighting device according to the present invention includes a laser in electrical communication with a power source to actuate the laser to produce a laser beam. The bow sighting device includes an arrow shaft having forward and rear ends with the laser positioned in the arrow shaft such that the laser beam projects through the forward end. A focusing lens may be positioned at the forward end through which the laser beam passes. The sighting device may include a nock at the rear end and a pushrod configured such that the pushrod urges the power source into connection with the laser when the arrow shaft is placed in ready-to-fire configuration relative to the bow. The bow sighting device simplifies hunting with a compound bow or crossbow by providing a visual indication of exactly where the arrow shaft is aimed.

This invention relates generally to sighting devices and, more particularly, to a bow sighting device for focusing laser light on a target utilizing a laser mounted inside or outside of an arrow shaft.
In 2004, there were 14,283,920 deer hunters in the United States according to the Deer Hunter's Almanac. Of these, 3,183,643 were archery hunters. One reason that more deer hunters do not use compound bows may be the relative complexity of bow hunting equipment as compared to gun hunting equipment. Another reason most deer hunters prefer to use guns is that shots taken with bows often miss their targets, resulting in lost arrows or wounded (not killed) game. Sighting a compound bow during hunting or sighting a crossbow prior to an actual hunt can be a difficult endeavor.
Various devices have been proposed in the art for aiding a bow hunter in sighting or targeting a hunted animal. Sighting accessories may be mounted to the frame or strings of a compound bow for use by the hunter. Crossbows, and more particularly their targeting scopes, may also be "sighted in" by adjusting windage and elevation settings such that the hunter can achieve greater accuracy during a hunt although this is often a trial and error task. Once properly sighted, however, the hunter has confidence that he will hit whatever he is aiming at when he pulls the trigger. Although the prior devices and proposals are assumably effective for their intended purposes, the existing devices do not provide a virtually guaranteed means for targeting and hitting a deer or a sighting target.
Therefore, it would be desirable to have a sighting device that visually identifies exactly what an arrow is aimed at and where it will hit when released. Further, it would be desirable to have a bow sighting device that may be mounted directly in-line with the arrow shaft itself. In addition, it would be desirable to have a bow sighting device with visual identification means for use with compound bows or crossbows.


There is described a combustion method which completely incinerates substances to be burned, particularly non-industrial wastes and industrial wastes, without involvement of generation of harmful substances. Under the combustion method, a portion of or substantially all triplet oxygen molecules involved in combustion are excited to singlet oxygen molecules, and substances to be burned are incinerated in the presence of singlet oxygen. Microwave discharge or photosensitization reaction is employed for exciting triplet oxygen to singlet oxygen.

1. Field of the Invention
The present invention relates to a method for incinerating substances, and more particularly, to a combustion method suitable for incinerating non-industrial wastes and industrial wastes.
2. Description of the Related Art
Incineration of a substance is usually carried out by means of a high-temperature oxidative reaction between oxygen contained in air and the substance, and therefore the presence of oxygen-containing air is indispensable for combustion. Air surrounding the planet has been considered to be formed during the course of a long history of evolution from the Genesis era. The era at which air has become substantially equal in composition to that at the present time, particularly, the time when the oxygen content of air substantially reached its oxygen current level, is not known with certainty. At least in terms of atmospheric composition, it is believed that there is not much difference between air that existed at the time when the human beings emerged and air that exists now. Primitive men should have observed, as one type of natural phenomenon, combustion in such forms as spontaneous ignition typified by a forest fire. Combustion per se is a natural phenomenon which has been well known since time immemorial. Since primitive man mastered fire, which is considered to have taken place far back into the prehistoric period, the techniques for mastering fire have probably been utilized actively, as combustion method, for the sake of our lives.
Although the majority of substances are completely burned during the course of combustion and are converted to stable oxides, some of the substances are incompletely burned and yield various types of volatile, less-volatile, and nonvolatile products. For example, when organic substances, such as ordinary organic compounds, are completely burned, water and carbon dioxides are largely produced. More specifically, when cellulose which is the principal constituent of paper or soybean oil is completely burned, water and carbon dioxides are produced. In contrast, if the cellulose or soybean oil is incompletely burned, various types of unburned substances, e.g., carbon monoxides, aldehyde, and soot are exhausted and a polynuclear aromatic compound, such as pyrene, is produced from the cellulose. Tobacco smoke and exhaust gas from a car are also known to contain various types of products resulting from incomplete combustion.
Unburned products contain substances deleterious to the global environment or human health. Particularly, toxic substances which are also known as environmental hormone and act as endocrine disturbing chemicals, such as dioxin, are produced in an incinerator as a result of incineration of wastes at insufficient temperatures. Serious environmental pollution caused by such toxic substances have recently been considered a global social problem. All the countries of the world, including Japan, are required to take immediately measures against such pollution.
In light of the present situation set forth, the object of the present invention is to provide a combustion method, by which substances to be incinerated, particularly, non-industrial wastes and industrial wastes, are completely burned without involvement of generation of harmful substances.


Aspects of the disclosure provide a bipolar transistor structure with an elevated extrinsic base, and related methods to form the same. A bipolar transistor according to the disclosure may include a collector on a substrate, and a base film on the collector. The base film includes a crystalline region on the collector and a non-crystalline region adjacent the crystalline region. An emitter is on a first portion of the crystalline region of the base film. An elevated extrinsic base is on a second portion of the crystalline region of the base film, and adjacent the emitter.

In the microelectronics industry as well as in other industries involving construction of microscopic structures, there is a continued desire to reduce the size of structural features and microelectronic devices and/or to provide a greater amount of circuitry for a given chip size. One type of transistor architecture is the bipolar junction transistor (BJT). A BJT refers to a transistor formed of three adjacent semiconductor regions (respectively known as emitter, base, and collector) with alternating conductivity types (e.g., N-P-N or P-N-P). Conventional approaches to form a BJT on a semiconductor substrate form an extrinsic base on an intrinsic base via conventional epitaxy. Such an approach may cause unacceptably rough surface topography on the top of the extrinsic base in small scale BJTs. Rough surface topography may be associated with subsequent processing and/or performance drawbacks.

Bipolar transistor with elevated extrinsic base and methods to form same


A device for turning a container about a turning axis is provided. The device includes a stationary holding member and two bearing members which are spaced apart along the turning axis on each side of a space for receiving a container, and which are capable of being used for bearing on the container while enabling the rotation of the container about the turning axis relative to the bearing members. The device includes a movable holding member that is mounted onto the stationary holding member so as to rotate about the turning axis, at least one bearing member being supported by the movable holding member while being mounted onto the movable holding member so as to rotate about the drive axis, the or each bearing member supported by the movable holding member not rotating about the turning axis relative to the stationary holding member when the movable holding member rotates about the turning axis relative to the stationary holding member.

A nuclear fuel assembly for Pressurised Water Reactor, "PWR", generally comprises of a bundle of nuclear fuel rods of great length arranged parallel to each other and a frame for holding the rods comprising of a bottom tie plate, a top tie plate, guide tubes being substituted for certain rods of the bundle and interconnecting between them the bottom tie plate and the top tie plate, and spacer grids attached to the guide tubes and distributed between the bottom tie plate and the top tie plate. The rods are held transversely and longitudinally by the spacer grids.
The nuclear fuel assembly has an elongated shape and its length is of the order of several meters, typically about four meters long, with a mass of several hundred kilogrammes, typically of the order of 600 to 800 kg. As a result, operations of handling nuclear fuel assemblies are often difficult.
In light of its use, the nuclear fuel assembly is arranged vertically in a nuclear reactor core, with the bottom tie plate being disposed at the bottom and top tie plate at the top.
During operation, it is possible that one of the fuel rods of the nuclear fuel assembly or the holding frame may be damaged and must be replaced. In addition, the fuel rods are regularly extracted for the purposes of carrying out laboratory examination or for reintegration into the bundle of rods of another fuel assembly for experimental purposes.
Nuclear fuel assemblies are generally designed so as to be able to extract each rod from the frame after the dismantling of one of the tie plates. In general, the extraction of the rod is carried out from the top after the dismantling of the top tie plate. In some cases, for example in the event of breakage of a fuel rod and when the two pieces have to be extracted or when all of the fuel rods must be transferred from a damaged frame to a new frame, it may be necessary to carry out the extraction from the bottom of the assembly after dismantling of the bottom tie plate. In this case, it is necessary to first turn over the nuclear fuel assembly. All these operations are carried out under water in order to avoid exposure to radiation.
FR 2 666 680 discloses a turning assembly comprising of a nuclear fuel assembly container, also called "cell", and a device for turning the container. The container comprises two coaxial trunnions provided on two opposite faces of the container. The turning device comprises of a lifting beam capable of being suspended from a crane, the lifting beam consisting of two columns that are spaced apart in a manner so as to receive between them the container, and two bearing members positioned at the lower ends of the columns and capable of being used for bearing on the trunnions of the container while enabling the rotation of the container about a horizontal turning axis, the turning device further comprising of a drive arm mounted on the lifting beam so as to be rotatable around the turning axis in order to drive the container, supported on the supporting members, in rotation about the turning axis.
However, this turning assembly requires the use of a crane for suspending the lifting beam. The crane is thus monopolised and is no longer available to perform other operations, for example the operations of loading/unloading of nuclear fuel assemblies in the reactor core.
Moreover the turning operations using the lifting beam suspended from the crane are carried out in a maintenance pool over the cells for temporary storage of nuclear fuel assemblies. These cells must therefore be emptied for safety reasons, this necessitates the moving of nuclear fuel assemblies to be undertaken, which is very time intensive, before being able to turn over the nuclear fuel assembly on which repairs and/or replacement of fuel rods and/or of the support frame must be carried out.

Device for turning a container, particularly for nuclear fuel assembly, turning assembly, and nuclear power plant


An extendable tree trimming saw is made easy to handle by providing a foot plate on which to rest the weight of the pole and a winch for raising and lowering the saw. The extendable pole is pivotally connected to the foot plate, preferably through a coil spring or elastomeric mass that aides in holding the pole upright and restoring it to an upright position after a cutting operation.

This invention relates to extendable saws for trimming and pruning trees and similar tasks. Extendable power saws have in general been quite unwieldy, typically requiring an operator to maneuver a heavy chainsaw from the end of a pole. Other types have power units at one end of a pole connected to a saw blade at the other end through internal shafts and gears and are complex and expensive in addition to being unwieldy. The present invention provides for easy lifting and maneuvering of an extendable pruning saw.


When each live performance signal is transferred from one live performance providing apparatus to the next, with the live performance providing apparatuses having the respective connection orders thereof, the live performance signal is mixed with a live performance signal captured by the one apparatus. The end (n-th) live performance providing apparatus mixes a live performance signal captured by itself with the live performance signals mixed by all prior live performance apparatuses, thereby finally providing a complete live performance signal as a concert sound.

1. Field of the Invention
The present invention relates to a method and apparatus for producing and distributing live performance, and a live performance system including a live performance providing apparatus and a live performance management device, in which contents of performance (for example, audio signals resulting from performance) performed by a plurality of players at remote places are transmitted through a network communication and synthesized (mixed) to complete live performance.
2. Description of the Related Art
As communication networks, such as the Internet or a satellite communication, have advanced, a variety of modes of use of the networks have been developed. In the field of music playing, for example, a plurality of players (hereinafter, also referred to as performers) at remote places may play at the same time, and captured sounds may be mixed through the network on a real-time basis to produce a concert (ensemble) sound.
If a plurality of performers attempt to play music in synchronization through the network on a real-time basis, a limitation on transfer capacity of the network and a time delay in signal transfer presents difficulty in achieving synchronization among them. Live performance by performers at remote places through the network is thus difficult.

Method and apparatus for producing and distributing live performance


A shunt has a housing and a base. The base has a first set of electrodes extending across the base. A catheter is connected to the housing. The catheter has a longitudinal length, a proximal end, and a distal end. The catheter has a second set of electrodes extending along the longitudinal length of the catheter. At least two of the electrodes of said first set are electrically connected to two of the electrodes of the second set. The housing including a self sealing, needle penetrable outer housing wall. The system includes a probe assembly that is selectively penetratable through an outer housing wall.

Hydrocephalus is a neurological condition that is caused by the abnormal accumulation of cerebrospinal fluid (CSF) within the ventricles, or cavities, of the brain. CSF is a clear, colorless fluid that is primarily produced by the choroid plexus and surrounds the brain and spinal cord. CSF constantly circulates through the ventricular system of the brain and is ultimately absorbed into the bloodstream. CSF aids in the protection of the brain and spinal cord. Because CSF keeps the brain and spinal cord buoyant, it acts as a protective cushion or "shock absorber" to prevent injuries to the central nervous system.
Hydrocephalus, which affects children and adults, arises when the normal drainage of CSF in the brain is blocked in some way. Such blockage can be caused by a number of factors, including, for example, genetic predisposition, intraventricular or intracranial hemorrhage, infections such as meningitis, head trauma, or the like. Blockage of the flow of CSF consequently creates an imbalance between the amount of CSF produced by the choroid plexus and the rate at which CSF is absorbed into the bloodstream, thereby increasing pressure on the brain, which causes the ventricles to enlarge.
Hydrocephalus is most often treated by surgically inserting a shunt system that diverts the flow of CSF from the ventricle to another area of the body where the CSF can be absorbed as part of the circulatory system. Shunt systems come in a variety of models, and typically share similar functional components. These components include a ventricular catheter which is introduced through a burr hole in the skull and implanted in the patient's ventricle, a drainage catheter that carries the CSF to its ultimate drainage site, and optionally a flow-control mechanism, e.g., shunt valve, that regulates the one-way flow of CSF from the ventricle to the drainage site to maintain normal pressure within the ventricles. The ventricular catheter typically contains multiple holes or apertures positioned along the length of the ventricular catheter to allow the CSF to enter into the shunt system.
Shunting is considered one of the basic neurosurgical procedures, yet it has the highest complication rate. The most common complication with shunting is obstruction of the system. Although obstruction or clogging may occur at any point along the shunt system, it most frequently occurs at the ventricular end of the shunt system. While there are several ways that the ventricular catheter may become blocked or clogged, obstruction is typically caused by growth of tissue, such as the choroid plexus, around the catheter and into the apertures. The apertures of the ventricular catheter can also be obstructed by debris, bacteria, or coagulated blood.
Some of these problems can be treated by backflushing, which is a process that uses the CSF present in the shunt system to remove the obstructing matter. This process can be ineffective, however, due to the small size of the apertures of the ventricular catheter and due to the small amount of flushing liquid available in the shunt system. Other shunt systems have been designed to include a mechanism for flushing the shunt system. For example, some shunt systems include a pumping device within the system which causes fluid in the system to flow with considerable pressure and velocity, thereby flushing the system. As with the process of backflushing, using a built-in mechanism to flush the shunt system can also fail to remove the obstruction due to factors such as the size of the apertures and the degree and extent to which the apertures have been clogged.
Occluded ventricular catheters can also be repaired by cauterizing the catheter to remove blocking tissue, thereby reopening existing apertures that have become occluded. Alternatively, new apertures can be created in the catheter. These repairs, however, may be incapable of removing obstructions from the ventricular catheter depending on the location of the clogged apertures. Additionally, the extent of tissue growth into and around the catheter can also preclude the creation of additional apertures, for example, in situations where the tissue growth covers a substantial portion of the ventricular catheter. Another disadvantage of creating new apertures to repair an occluded ventricular catheter is that this method fails to prevent or reduce the risk of repeated obstructions.
Because attempts at flushing or repairing a blocked ventricular catheter are often futile and ineffective, occlusion is more often treated by replacing the catheter. Although this can be accomplished by removing the obstructed catheter from the ventricle, the growth of the choroid plexus and other tissues around the catheter and into the apertures can hinder removal and replacement of the catheter. Care must be exercised to avoid damage to the choroid plexus, which can cause severe injury to the patient, such as, for example, hemorrhaging. Not only do these procedures pose a significant risk of injury to the patient, they can also be very costly, especially when shunt obstruction is a recurring problem.
Accordingly, there exists a need for a shunt system that minimizes or eliminates the risk of blockage or obstruction of the catheter apertures, and reduces the need for repeated repair and/or replacement.

System and method for clearing an implanted catheter that is connected to a shunt


A spill resistant fuel supply system (16) for a marine engine (12). The system (16) includes a generally sealed housing (46) in which is disposed a vapor separator (26), a high pressure pump (28) and/or a suction pump (24). The housing (46) prevents fuel that might leak from these components from openly collecting in the marine vessel (10). The housing (46) includes one or more walls (48, 50, 52) formed with included air columns (58) which act as thermal barriers to reduce the amount of heat energy transferred from the outside in. The included air columns (58) are preferably arrayed in side-by-side fashion and closed at both ends to trap air therein.

1. Field of the Invention
This invention relates generally to a fuel system for a marine internal combustion engine, and more particularly toward such a fuel system including a fuel spillage containment device.
2. Related Art
Many watercraft include an internal combustion engine configured to propel the craft through the water. The fuel supply system for such an engine is generally arranged so that fuel is supplied from a tank and delivered to the engine under high pressure. Engines are often placed in an enclosed, poorly ventilated space. The high temperature surrounding a marine fuel system and the inherent vibrations created by close proximity to the engine and jarring boat movement all work against the fuel system to increase the production of fuel vapors. Vapor in the fuel reduces its effectiveness and the efficiency of the pump used to deliver the fuel to the engine. Vapor separators have been developed to address this problem.
In order to limit the distance fuel must be pumped under positive pressure, it is common to locate the vapor separator and high pressure pump very close to the hot engine. Another problem encountered in marine applications is the potential for leaked fuel to collect in the watercraft thereby presenting a fire hazard. The prospect of a fire in a watercraft is considered substantially more serious than a fire in an automobile, due to the fact that fire in a watercraft can force occupants to evacuate into open water. The US Coast Guard has promulgated regulations pertaining to fuel systems used for marine vessels. One such regulation may be found in 33 CFR §183.590, which specifies a current fire test for marine fuel systems. In order to comply with this and other standards, a marine fuel system is required to meet the specified criteria without leaking fuel externally.
Examples of various marine fuel supply systems may be found by reference to U.S. Pat. No. 5,647,331 to Swanson issued Jul. 15, 1997, U.S. Pat. No. 6,032,654 to Kato issued Mar. 7, 2000, and U.S. Pat. No. 6,553,974 to Wickman et al. issued Apr. 29, 2003. Another example may be found by reference to U.S. Pat. No. 7,503,314 to Achor issued Mar. 17, 2009 and assigned to the assignee of the subject invention. The entire disclosure of U.S. Pat. No. 7,503,314 is hereby incorporated by reference and relied upon.
U.S. Pat. No. 5,645,004 to Holland, issued Jul. 8, 1997 and U.S. Pat. No. 6,532,888 to Enik, issued Mar. 18, 2003 describe various containment devices for marine vessels which recognize the issues and concerns associated with fuel spilled in marine applications. U.S. Pat. No. 5,645,004, for example, teaches the construction of an open tray placed near the site of a potential fuel spill. The tray is made of a special absorbent material designed to capture, contain and solidify any leaks or spills that may occur.
There is, nevertheless, a continuing desire to develop new and improved fuel spillage containment devices that may be implemented in hot, jarring marine applications. Such containment devices can preferably accommodate new fuel system installations, as well as retrofit installations in existing fuel systems. A containment device is also preferably relatively inexpensive, easy to manufacture, and easy to install.

Marine fuel system with spill control feature


The invention is a method of treating cancer comprising administering an effective amount of either a composition of three herbal extracts consisting essentially of 30% to 70% by weight Goldenseal, 20% to 40% by weight of Myrtle, and 5% to 20% by weight of Centaurea, or a composition of seven herbal extracts consisting essentially of 3% to 5% by weight Centaurea, 1.5% to 4% by weight Capsicum, 1.5% to 4% by weight Lobelia, 20% to 40% by weight Myrrh, 30% to 50% by weight Echinacea, 15% to 25% by weight Goldenseal, and 3% to 5% by weight Myrtle. The compositions were prepared by separately extracting each herb by mixing the herb in water, ethyl alcohol, or a mixture of water and ethyl ether, boiling and cooling the mixture, allowing the mixture to stand for about two weeks, filtering the mixture to obtain the liquid phase, and combining each of said extracts to obtain said compositions.

There are innumerable drugs which are used to combat a large variety of cancers. However, these drugs are made of individual or combinations of chemicals. While some are effective, many have side effects which prevent their long-term or recurrent use. In addition, there has been an increasing number of effective drugs which can no longer be used due to the resistance by the causative agent.

Natural composition extracted from plants used in the treatment of cancer


The present invention provides compounds of general formula 1 useful as potential phosphodiesterase3 (PDE3) inhibitory agents and a process for the preparation thereof. The derivatives of formula 1 can be employed as therapeutics in human and veterinary medicine, where they can be used, for example, for the treatment and prophylaxis of the following diseases: heart failure, dilated cardiomyopathy, platelet inhibitors, cancer and obstructive pulmonary diseases.

Congestive heart failure (CHF) is a major cause of death in patients with heart disease. Digitalis glycosides (Drug that is extracted from the leaves of the foxglove plant) have been used for the treatment of CHF for more than 200 years (Gheorghiade, M.; Zarowitz, B. J.; Am. J. Cardiol., 1992, 69, 48G). However, application of these agents are limited because of their narrow therapeutic window and their propensity that cause life-threatening arrhythmias (arrhythmogenic liability). Thus digitalis has been replaced by a new class of cardiotonic agents named as a well known PDE3 inhibitor Amrinone and Milrinone, a 2-oxopyridine derivative that has been introduced to the clinic for the treatment of CHF in place of digitalis (Kikura, M.; Levy, J. H.; Int. Anestesiol. Clin., 1995, 33, 21). These PDE inhibitors display a greater safety profile and improved efficacy on patient survival.
Phosphodiesterases are a class of intracellular enzymes responsible for the hydrolysis of cyclic adenosine monophosphate (c-AMP) and cyclic guanosine monophosphate (c-GMP) which are involved in the regulation of important cell functions, such as secretion, contraction, metabolism, and growth (Potter, B. V. L.; Transmembrane Signalling Second Messenger Analogues and Inositol Phosphates. In Comprehensive Medical Chemistry; Hansch, C.; Sammes, P. G.; Taylor, J. B.; Eds. Pergamon Press: Oxford, 1990; pp 102-128). On the basis of structure, and substrate specificity PDE enzymes can be grouped into eleven different families, PDE1 to PDE11 (Beavo, J. A.; Physiol. Rev., 1995, 75, 725).
Each PDE isozyme has a conserved C-terminal catalytic domain and unique N-terminal regulatory domain. These isozymes are found in different tissues and cells of the humans such as smooth muscle, brain, heart, lung, platelets, lymphocytes etc. and in other species (Bender, A. T.; Beavo, J. A.; Pharmacol Rev., 2006, 58, 488). PDE3 and PDE4 are well established in cardiovascular tissues (Nicholson, C. D.; Challiss, R. A. J.; Shahid, M.; Trends Phahrmacol Sci., 1991, 12, 19). Among all subtypes of PDE, PDE3 is predominantly expressed in heart and platelets. Thus PDE3 play an important role in heart and platelet (Palson, J. B.; Strada, S. J.; Annu. Rev. Pharmacol. Toxicol., 1996, 36, 403).
Inhibition of PDE brings about various physiological reactions, for example inhibition of PDE3enhances myocardial contraction, produces vasodilatation, and suppresses platelet aggregation (Abadi, A. H.; Ibrahim, T. M.; Abouzid, K. M.; Lehmann, J.; Tinsley, H. N.; Gary, B. D.; Piazza, G. A.; Bioorg. Med. Chem., 2009, 17, 5974). These are the reasons why PDE3 inhibitors can be used to treat heart failure.
In addition, the PDE3 isozyme is specific for c-AMP and has no effect on c-GMP and calmodulin. Therefore, inhibition of PDE3 isoenzyme in cardiovascular tissues may lead to high levels of c-AMP and consequent inotropic effect.
Recent studies revealing that PDE3, PDE4, and PDE5 isozymes are over expressed in cancerous cells compared with normal cells. Thus inhibition of PDE3 together with other PDE's may lead to inhibition of tumor cell growth and angiogenesis (Cheng J. B.; Grande, J. P.; Exp. Biol. Med., 2007, 232, 38).
Recently, PDE3/4 inhibitors have attracted considerable interest as potential therapeutic agents for diseases including chronic obstructive pulmonary disease (COPD). PDE4 or PDE3 inhibitors alone are unable to inhibit spasmogen-induced contraction of human airway, but in combination act synergistically. While PDE3 inhibitor has been shown to inhibit cough, PDE4 inhibitor may be able to stimulate mucociliary clearance. This diverse spectrum of biological effects has thus implicated PDE3/4 inhibitors as potential therapeutic agents for a range of disease indications including COPD. (Banner, K. H.; Press, N. J.; Br. J. Pharmacol., 2009, 157(6): 892-906.)
The present invention describes the synthesis of novel indolizine based derivatives as inhibitors of phosphodiesterase3 (PDE3). PDE3 inhibitors are useful for the prevention of heart failure and inhibit platelet aggregation.
The following references are examples for the synthesis and biological evaluation of some of the PDE or PDE3 inhibitors. The prior art contain useful information and discussion on the preparation and properties of PDE inhibitors.
U.S. Pat. No. 4,963,561, reported synthesis of novel 1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones having an aryl or heteroaryl group on the 6th position, useful as phosphodiesterase inhibitors, prepared by reacting a 2-amino-5-(aryl or heteroaryl)pyridine-3-carboxylic acid with diphenylphosphorylazide.
US Pat. No. 20070208051, reports PDE3/4 inhibition by novel N-(alkoxyalkyl) carbamoyl substituted 6-phenyl-benzonaphthyridine derivatives.
Recently our publication reported [Ravinder et al Bioorg. Med. Chem. Lett., (2012)] Synthesis and Evaluation of Novel 2-Pyridone Derivatives as Inhibitors of Phospho-diestarase3 (-PDE3): A Target for Heart Failure and Platelet Aggregation.
Wang et al., Bioorg Med Chem Lett., (2012 Feb. 9) reports synthesis and evaluation of Sildenafil analogs against human phosphodiesterase5 (PDE5).

Process for preparation of indolizine based derivatives as potential phosphodiestrase 3 (PDE3) inhibitors

COUNCIL OF SCIENTIFIC & INDUSTRIAL RESEARCH


A method for transferring electrical power in the sea includes generating AC power, guiding, at least partially underwater, the AC power through a cable from a first end of the cable to a second end of the cable, and changing a frequency of the AC power guided through the cable based on a value of power consumption of a load connected to the second end of the cable.

Conventional electrical AC power cable transmission may be limited in distance due to cable properties. Typical maximum AC transmission distance at 50/60 Hz may be between 100 km and 200 km. If longer distances are needed, DC transmission is used. For subsea power, it is useful to reach out farther than 200 km. For arctic areas, hydro carbon reservoirs with step outs up to 600 km from shore are explored. AC power may be used for powering consumers at a subsea exploration site, such as pumps, compressors, motors etc. Therefore, in a conventional system, the DC power transmitted to the sea ground is converted into AC power, in order to be appropriate to power the consumers at the subsea exploration site. However, converting the DC power to an AC power involves large and heavy equipment that poses a number of problems for setting up the exploration site and also increases the costs of the system. When designing a subsea power grid, reliability may be one of the main factors. To increase the reliability of a subsea power grid, it may be useful to limit the complexity and also to limit components with low reliability, such as non-redundant types of components. Only medium voltage distribution technology for AC solution may be reliable. This means that DC power is converted to AC power subsea for subsea DC transmission systems. The DC to AC converting system may be a complex system consisting of a high number of components, and may reduce reliability relative to a subsea AC transmission system.
There may be a need for a method and an arrangement for transferring electrical power in the sea, which facilitates powering of electrical AC power of subsea consumers with step out much longer than today's typical maximum transmission distance of 100-200 km. Benefits may also be provided if this increases the reliability and at the same time reduces the size of the equipment. Further, there may be a need to provide AC consumers with AC power in a simpler manner involving smaller or lighter equipment than a conventional system.

Transferring electrical power for subsea applications


A system for trimming interior walls includes a plurality of elongate boards forming both base boards and fenestration casing boards for mounting on a respective wall along an edge of the wall for forming an attractive edge face of the wall. Each board has a front face with a continuously longitudinally extending groove with the rear face of the board being fastened to the wall by a series of screws at spaced positions along the board with the screws being recessed in the groove. An extruded plastic strip is inserted into the groove along the length of the board so as to cover the groove and the screws therein. The casing boards include an extra fastening connector along the rear of the board at the jamb. Corner pieces are provided which are hollow moldings to cover the ends of the boards with either a groove for a part of the strip or a simulated ridge matching the strip.

Typically base boards, window and door casings and the like are fastened to a wall by finishing nails which then require to be patched with a filler and finish painted over the filler. Thus in most cases the boards are supplied in a prime paint condition so that the finish coat is applied simultaneously over the filler and the prime coat. This requires considerable labor to fill and paint the small holes left by the finish nails. Also it is generally not possible to remove the board for adjustment or to work on the adjacent wall or floor since the nails generally cause splitting of the board and prevent replacement of the board after it is removed.


The present invention relates to an OPCPA apparatus. The OPCPA of the present invention includes an optical pulse stretcher (100) for outputting chirped laser light using odd-order dispersion (third-order dispersion is mainly used). A pump laser (200) outputs pump laser light. An OPA unit (300) receives the pump laser light and the chirped laser light (signal), amplifies the signal using the pump laser light, and generates an idler. An optical signal separation unit (400) separates output light of the OPA unit into the signal, the idler, and remaining light (pump). An optical pulse compressor (600) compensates for pulse chirping caused by odd-order dispersion that is imparted by the optical pulse stretcher, thus temporally compressing the signal and the idler, which overlap each other.

Generally, Optical Parametric Chirped Pulse Amplification (OPCPA) is used to amplify an ultrashort mode-locked laser source existing in a band ranging from several femtoseconds (fs; 10−15 seconds) to several hundreds of femtoseconds. OPCPA is a new optical amplification technique of combining conventional Chirped Pulse Amplification (CPA) technology with the concept of Optical Parametric Amplification (OPA), and is laser amplification technology which has recently been actively researched.
In a conventional OPCPA apparatus, an antiparallel diffraction grating structure of applying long-wavelength preceding-type chirping (positive chirping by the antiparallelism of a grating pair) is first applied to an optical pulse stretcher, and a parallel diffraction grating structure of applying short-wavelength preceding-type chirping after amplification has been performed (negative chirping by the parallelism of a grating pair) is applied to an optical pulse compressor, so that the temporal stretch of a pulse occurring in the optical pulse stretcher is compensated for.
Such an OPCPA apparatus is described in detail with reference to FIGS. 1 to 4.
FIG. 1a is a simple diagram of a conventional OPCPA apparatus, and FIG. 1b is a detailed diagram showing the construction of the OPCPA apparatus of FIG. 1a.
Referring to FIGS. 1a and 1b, the conventional OPCPA apparatus includes an optical pulse stretcher 10, a pump-injection dichroic mirror 80, a pump laser 20, an Optical Parametric Amplification (OPA) unit 30, a pump-removal dichroic mirror 40, a beam dumper 50, and an optical pulse compressor 60.
The optical pulse stretcher 10 temporally stretches laser light by varying the optical path of the laser light for each frequency. That is, the optical pulse stretcher 10 stretches the pulse length (pulse duration) of the output light of an ultrashort laser from an original band of several femtoseconds (fs; 10−15 seconds)/several tens of picoseconds (ps; 10−12 seconds) to a stretch band of several hundreds of picoseconds (ps; 10−12 seconds)/several nanoseconds (ns; 10−9 seconds) (in relation to this technology, refer to relevant CPA technology devised to realize efficient optical amplification and to avoid damage to optical parts).
The optical pulse stretcher used in this case and provided in the previous stage of the amplification stage applies dispersion according to wavelength, and stretches the temporal length of a pulse (temporal pulse duration) as a result of the spatial dispersion (optical path length difference), which is referred to as pulse chirping.
In the present specification, the output light of the optical pulse stretcher 10 is briefly referred to as a 'signal'.
In the conventional OPCPA apparatus, light passes through the above optical pulse stretcher, and thus a temporally chirped signal (long wavelength precedes short wavelength) is output, as shown in FIG. 4.
The pump laser 20 is a device for supplying pump laser light (also briefly referred to as a 'pump').
The pump-injection dichroic mirror 80 is a device for receiving the pump and the signal, and transmitting the pump and the signal to a subsequent stage (OPA unit).
The OPA unit 30 amplifies the signal using the pump, and generates an idler. Accordingly, the pump itself is attenuated to a corresponding degree by energy conservation.
Then, the output light of the OPA unit includes the pump, the amplified signal and the idler.
Optical parametric amplification is classified into collinear phase matching and noncollinear phase matching according to the phase matching configuration between the pump and the signal. When a design condition is selected properly in the noncollinear phase matching configuration, a gain bandwidth broader than that of the collinear phase matching can be obtained. Accordingly, at the time of performing broadband Optical Parametric Amplification (broadband OPA), noncollinear phase matching is generally used. In this case, since it is difficult to subsequently use an idler due to angular dispersion according to wavelength, the idler is removed using a beam dumper.
The pump-removal dichroic mirror 40 separates the output light of the OPA unit 30 into a signal and remaining light (idler and pump), and varies the optical paths thereof.
For example, the pump-removal dichroic mirror 40 reflects the signal, passes the idler and the pump therethrough, and removes the passed idler and pump using the beam dumper 50.
Generally, since the output light, emitted from the ultrashort laser oscillator itself, has a very small amount of energy per pulse, the output light is amplified through several stages of amplification (OPA) means.
In this case, the amplification means includes pump lasers 21 and 22, OPA units 31 and 32, pump-removal dichroic mirrors 41 and 42, and beam dumpers 51 and 52. The amplification means is provided in a plural number, and thus a signal having a desired intensity can be obtained.
As described above, when the amplification of the signal to the desired intensity is performed, temporal compression is finally performed using the optical pulse compressor 60.
Reference numerals 71 to 74 are beam path changing mirrors for changing the paths of light (beam).
FIGS. 2a to 2d are diagrams showing the construction of the optical pulse stretcher of the conventional OPCPA apparatus, FIG. 2a illustrating an antiparallel diffraction grating structure (refraction type), FIG. 2b illustrating an antiparallel diffraction grating structure (reflection type), and FIGS. 2c and 2d illustrating the plan view and side view of an antiparallel diffraction grating structure (Offner—triplet type).
First, referring to FIG. 2a, the refraction-type diffraction grating structure includes two diffraction gratings (respectively designated as 'first diffraction grating' and 'second diffraction grating') 111 and 112, two lenses 113 and 114, and a single roof mirror 115.
The roof mirror 115 functions to reflect incident light at a changed height.
The optical path thereof is described. After light is incident on and diffracted from the first diffraction grating 111, the diffracted light passes through the two lenses 113 and 114 and is incident on and diffracted from the second diffraction grating 112. The diffracted light is incident on the roof mirror 115, and is reflected from the roof mirror 115 at a changed height. The reflected light is incident on the beam path changing mirror 71 through the second diffraction grating 112, the two lenses 114 and 113, and the first diffraction grating 111.
In this case, a corresponding separation distance (that is, a corresponding separation distance between gratings which has same chirping power, in parallel grating structure) is represented by 2f−s1−s2, where f denotes the focal distance of the lenses 113 and 114, and s1 and s2 denote the distances between the lens 113 and the diffraction grating 111 and between the lens 114 and the diffraction grating 112, respectively.
In the refraction-type antiparallel diffraction grating structure of FIG. 2a, the following problems may occur. That is, in the refraction-type antiparallel diffraction grating structure including the lenses 113 and 114, chromatic aberration caused by the lenses, etc. may occur.
In order to solve the problem of chromatic aberration caused by the lenses, the reflection-type antiparallel diffraction grating structure of FIG. 2b has been devised.
Referring to FIG. 2b, the reflection-type antiparallel diffraction grating structure includes two diffraction gratings (respectively designated as 'first diffraction grating' and 'second diffraction grating') 121 and 122, two cylinder mirrors 123 and 124, and a single roof prism 125.
The roof prism 125 performs the same function as the roof mirror of FIG. 2a.
The optical path thereof is described. After light is incident on and diffracted from the first diffraction grating 121, the diffracted light is incident on and diffracted from the second diffraction grating 122 through the two cylinder mirrors 123 and 124. The diffracted light is incident on the roof prism 125. The incident light is reflected from the roof prism 125 at a changed height, and the reflected light is incident on the beam path changing mirror 71 through the second diffraction grating 122, the cylinder mirrors 124 and 123, and the first diffraction grating 121.
In this case, a corresponding separation distance is represented by 2f−s1−s2, where f denotes the focal distance of the cylinder mirrors 123 and 124, and s1 and s2 denote the distances between the cylinder mirror 123 and the diffraction grating 121, and between the cylinder mirror 124 and the diffraction grating 122.
The reflection-type antiparallel diffraction grating structure of FIG. 2b may have the following problem. Specifically, a problem of aberration (such as astigmatism and coma) caused by the incline of the two cylinder mirrors relative to the optical axis occurs.
In order to solve the above problem, an Offner-triplet structure of FIG. 2c (plan view) and FIG. 2d (side view) has been devised.
Referring to FIGS. 2c and 2d, the Offner-triplet structure includes a single diffraction grating 131, two spherical mirrors (respectively designated as 'first spherical mirror' and 'second spherical mirror') 132 and 133 having different sizes, and a single roof prism 134.
In the above construction, the roof prism 134 performs the same function as the roof mirror of FIG. 2a.
The second spherical mirror 133 is larger than the first spherical mirror 132.
The optical path of the Offner-triplet structure is described. After light is incident on and diffracted from the diffraction grating 131, the diffracted light is incident on and reflected from the second spherical mirror 133. After the reflected light is incident on and reflected from the first spherical mirror 132, the reflected light is incident on and reflected from the second spherical mirror 133 again. The reflected light is incident on and diffracted from the diffraction grating 131 again, and the diffracted light is incident on the roof prism 134. The incident light is reflected from the roof prism 134 at a changed height. The reflected light passes through the diffraction grating 131, the second spherical mirror 133, and the first spherical mirror 132, and is then output through the second spherical mirror 133 and the diffraction grating 131.
In this case, a corresponding separation distance is represented by 2(R−s), where R denotes the radius of curvature of the second spherical mirror 133, and s denotes the distance from the second spherical mirror 133 to the diffraction grating 131.
FIG. 2e is a graph showing signal chirping performed through the antiparallel diffraction grating structure in the conventional optical pulse stretcher.
FIG. 2e illustrates the results of computer simulation of the signal chirping generated by a typical optical pulse stretcher. In the simulation with the Offner-triplet structure of FIGS. 2c and 2d, parameters for the diffraction gratings are set as follows. That is, first-order diffraction is used, the number of grooves of the diffraction grating is set to 1740 lines/mm, the angle of incidence is set to 62.8°, the angle of diffraction is set to 70.8°, and a corresponding separation distance is set to 530 mm.
As a result, the signal having an 8 nm spectrum ranging from 1050 nm to 1058 nm) centered on a wavelength of 1054 nm is stretched by about 800 ps. Such a value (800 ps) is the value obtained by dividing an optical path-length difference by the speed of light, where the optical path-length difference is 240 mm, and the speed of light is three hundred thousand km/s.
For reference, laser light having passed through the optical pulse stretcher has a pulse structure which is temporally stretched according to wavelength. In this case, the reason an optical pulse is temporally stretched according to wavelength is described below. That is, ultrashort laser light includes laser light having different wavelength components. Accordingly, as light passes through the diffraction grating structure for respective wavelength components, the light travel distance thereof varies, and consequently an optical pulse is temporally stretched due to the difference between the temporal delays of respective wavelength components, attributable to the variation in light travel distance.
FIG. 3a is a diagram showing the construction of the optical pulse compressor of the conventional OPCPA apparatus.
Referring to FIG. 3a, the parallel diffraction grating structure includes two diffraction gratings 141 and 142 having a parallel arrangement, and a single roof mirror 143 for reflecting incident light at a changed height.
The optical path thereof is described below. After light is incident on and diffracted from the first diffraction grating 141, the diffracted light is incident on and diffracted from the second diffraction grating 142. The diffracted light is incident on the roof mirror 143, and is reflected from the roof mirror 143 at a changed height. The reflected light is output through the second diffraction grating 142 and the first diffraction grating 141.
In this case, the corresponding separation distance can be represented by the distance between the two diffraction gratings 141 and 142.
FIG. 3b is a graph showing signal chirping performed by a parallel diffraction grating structure in the conventional optical pulse compressor.
FIG. 3b illustrates the results of computer simulation of the signal chirping structure generated in a typical optical pulse compressor. In the parallel diffraction grating structure of FIG. 3b, parameters for diffraction gratings are set as follows. That is, −1st-order diffraction is used, the number of grooves of each diffraction grating is set to 850 lines/mm, the angle of incidence is set to 5.0°, the angle of diffraction is set to 79.4°, and a corresponding separation distance is set to 692 mm.
As a result, a signal having an 8 nm spectrum centered on a wavelength of 1054 nm is temporally stretched by about 800 ps. In this case, the optical path-length difference is about 240 mm.
Further, such an optical pulse compressor can temporally compress the signal, which has an 8 nm spectrum centered on a wavelength of 1054 nm and which has been temporally stretched by a typical optical pulse stretcher by about 800 ps, to the original state thereof.
Next, the operation and effects of the conventional OPCPA apparatus are described below.
First, an original signal passes through the optical pulse stretcher 10 having the construction of FIGS. 2a to 2d, so that a temporally stretched waveform, in which a long wavelength precedes a short wavelength, is output (refer to FIG. 4).
The output light (signal) of the optical pulse stretcher 10 is incident on a first pump-injection dichroic mirror 81 through the beam path changing mirrors 71 and 72, and the pump light output from the first pump laser 21 is also incident on the first pump-injection dichroic mirror 81.
Both the signal and pump are incident on the first OPA unit 31. In the first OPA unit 31, as the signal is amplified using the pump, an idler is generated, and the pump itself is attenuated.
Consequently, the output light of the first OPA unit 31 includes the pump, the amplified signal, and the idler.
The output light is incident on the first pump-removal dichroic mirror 41, and is separated into the amplified signal and remaining light (pump and idler). That is, both the attenuated pump and the idler pass through the first pump-removal dichroic mirror 41 and are removed by the first beam dumper 51, and the amplified signal is reflected from the first pump-removal dichroic mirror 41.
If the amplified signal succeeds in reaching the level of aimed intensity or more, the amplified signal is incident on the optical pulse compressor 60, otherwise, it undergoes the above process again (process from the pump-injection dichroic mirror to the beam dumper).
That is, if the signal (amplified signal) reflected from the first pump-removal dichroic mirror 41 fails in reaching the level of aimed intensity or more, the signal is incident on the other pump-injection dichroic mirror (second pump-injection dichroic mirror) 82, and the pump generated from the second pump laser 22 is also incident on the second pump-injection dichroic mirror 82. Thereafter, the signal and the pump pass through the second OPA unit 32, the second pump-removal dichroic mirror 42, and the second beam dumper 52. The above process is repeated until the above signal is amplified to a predetermined intensity or more.
Finally, the amplified signal is incident on the optical pulse compressor 60, and the optical pulse compressor 60 temporally compresses the amplified signal.
However, the conventional OPCPA apparatus has the following problems.
That is, the conventional OPCPA apparatus forms a linear pulse chirping structure using second-order dispersion (Group Velocity Dispersion: GVD). However, such a structure is problematic in that, since the second-order dispersion terms in the signal and idler, which are the output light of the OPA unit, have the same magnitude and have opposite signs, compensation for pulse chirping is difficult in the optical pulse compressor. Therefore, an idler having energy intensity roughly equal to that of the amplified signal cannot be generally utilized, and must be discarded.
For a detailed description of dispersion, reference may be made to FIG. 7.

Apparatus for spectrum-doubled optical parametric chirped pulse amplification (OPCPA) using third-order dispersion chirping

Korea Advanced Institute of Science and Technology


An RFID tag formed on an original includes a storage unit which stores data representing, e.g., the number of times of scan of the original and the generation from a parent original, and a transmitter/receiver which transmits and receives the data by radio. A read/write circuit receives data from an RFID tag of an original by radio. On the basis of the received data, read of the original is controlled. While the original is being read, the received data is edited in accordance with the control. The read/write circuit transmits and writes the edited data in the RFID tag.

Recently, a small-sized IC chip containing a radio device called an RFID (Radio Frequency Identification) tag and a memory is attracting attention. The RFID tag is also called an IC tag or mu-chip, and a very small square chip of 0.04 mm side has been announced as a non-rewritable ROM type chip.
Conventionally, a copying apparatus which copies an original having this RFID tag is known (Japanese Patent Laid-Open No. 2002-337426). This reference proposes a technique by which user ID information is input from an operation unit of the copying machine, and written in the RFID tag on an original. In this way, data of a person who copied this original can be stored in the RFID tag and managed.
It is sometimes desirable to limit image read depending on the type of original. For example, a method of limiting scan of an original by forming a watermark on the original is known. In this method, however, the watermark is reflected on all read images. This is inconvenient. Therefore, there are needs of more convenient and flexible techniques allowing image read at least a predetermined number of times.
Also, in some cases a certain parent original is copied to form a child original and this child original is copied to form a grandchild original. When copying is thus repeated over a number of generations, the image deteriorates. Accordingly, it is desirable to avoid, by some means, to repeat image read or copying over a number of generations to such an extent that the image quality of the original is no longer maintainable.

Image reading/forming apparatus and method


A headphone device includes a sound amplifying member, a connecting member and a fixing member. The sound amplifying member includes a first speaker and a second speaker for outputting a sound. The connecting member is interconnected between the first speaker and the second speaker and made of first flexible material. The connecting member is flexibly wound around the first speaker and the second speaker. The fixing member is coupled to the sound amplifying member for securing the connecting member thereon after the connecting member is wound around the first speaker and the second speaker.

Nowadays, portable media players such as portable CD players, MP3 players and the like become popular in modern societies due to some advantages such as small size, light weightiness and easy portability. On account of their portability, the users can use such portable media players everywhere they are. In order to hear songs from the portable media player, some accessories such as earphones are indispensable. Since the structure of the earphones may influence the tone quality and the portability of the portable media player, it is important to select suitable earphones matching the portable media player.
Generally, the earphone devices offered by the manufacturers of the portable CD players or the MP3 players are plain earplug types, which have plain sound isolation and plain tone quality. When this earplug type earphone device is used, the volume of the portable CD player or the MP3 player is unconsciously turned up to a high level because the noisy sounds in the surroundings are not effectively isolated. After exposure to such a noisy environment for a long term, the user is readily suffered from hearing loss. For a purpose of protecting from hearing loss, a headphone device having ear muffs is additionally purchased. The headphone device is usually divided into two categories: a vertical headphone device that arches over the head and a horizontal headphone device that rests on the ears. The vertical headphone device that arches over the head is both bulky and cumbersome for the portable use in the portable CD player or the MP3 player. Whereas, the horizontal headphone device that rests on the ears includes a pair of supporting members for supporting the speaker units. According the user's demand, the horizontal headphone device is attached to the rear head of a user as the supporting members rest on the ears. Typically, the vertical headphone device that arches over the head has a rigid hoop structure, and is therefore not feasible for portability or storage. Whereas, the horizontal headphone device that rests on the ears is advantageous for portability or storage because no rigid hoop structure is used. In comparison with the earplug type earphone device, however, the horizontal headphone device is unsatisfactory in portability or storage because the overall volume of the horizontal headphone device is increased and the two speaker units are distant from each other.
For a purpose of solving the drawbacks described above, as shown in FIG. 1(a), an improved headphone device is disclosed in U.S. Pat. No. 6,385,325 B1, which is hereby fully incorporated by reference. Referring to FIG. 1(a), the headphone device 1 comprises a rigid hoop structure 11, a first supporting member 12, a second supporting member 13, a first speaker unit 14 and a second speaker unit 15. The hoop structure 11 is rotatable about a first fulcrum portion 111 in the direction indicated by the arrow A. The first supporting member 12 and the second supporting member 13 are coupled with the hoop structure 11. When the headphone device 1 is attached to the rear head of a user, the first supporting member 12 and the second supporting member 13 rest on the user's ears. The first speaker unit 14 and the second speaker unit 15 are supported by the first supporting member 12 and the second supporting member 13, respectively. The first supporting member 12 and the second supporting member 13 are rotatable about a second fulcrum portion 121 and a third fulcrum portion 131, respectively, in the direction indicated by the arrow B. For collapsing the headphone device 1, the first fulcrum portion 111 of the hoop structure 11, the second fulcrum portion 121 of the first supporting member 12 and the third fulcrum portion 131 of the second supporting member 13 are cooperatively operated. First of all, as shown in FIG. 1(b), the first supporting member 12 and the second supporting member 13 are rotated in the direction indicated by the arrow B about the second fulcrum portion 121 and the third fulcrum portion 131, respectively, so that the first speaker unit 14 and the second speaker unit 15 along with the supporting member 12 and the second supporting member 13 approach toward the hoop structure 11. Then, the hoop structure 11 is rotated in the direction indicated by the arrow A, so that the first speaker unit 14 and the second speaker unit 15 approach each other. Afterwards, the first speaker unit 14 and the second speaker unit 15 are housed in a region surrounded by the first supporting member 12, the second supporting member 13 and the hoop structure 11, as can be seen in FIG. 1(c).
Although the headphone device of FIG. 1 is storable when collapsed to a compact size, this headphone device still has some drawbacks. For example, since the hoop structure 11 is made of rigid material, the compact size is not satisfied. As shown in FIG. 1(c), due to the rigid hoop structure 11, there is still large space between the first speaker unit 14 and the second speaker unit 15. Therefore, there is a need to collapse the headphone device to a reduced size. In addition, the first fulcrum portion 111, the second fulcrum portion 121 and the third fulcrum portion 131 are readily loosened after many rotating and collapsing cycles. Under this circumstance, the headphone device fails to be well collapsed.
In views of the above-described disadvantages resulted from the prior art, the applicant keeps on carving unflaggingly to develop a headphone device according to the present invention through wholehearted experience and research.


A method for manufacturing a structure having an air gap includes following steps. A plurality of patterns is formed in a pattern region of a substrate. A sacrificial layer is formed on the substrate, and a top surface of the sacrificial layer is lower than a top surface of the patterns to expose a plurality of upper portions of the patterns. A hard mask layer is formed to cover the sacrificial layer and the upper portions of the patterns. An etching-back process is performed to the hard mask layer to expose the sacrificial layer outside the pattern region, and the hard mask layer remaining inside the pattern region seals the opening between the upper portions of the patterns. The sacrificial layer is removed to form an air gap between the two adjacent patterns.

1. Field of the Invention
The invention relates to a method for manufacturing a semiconductor device, and particularly relates to a method for manufacturing a structure having an air gap.
2. Description of Related Art
Currently, a structure having an air gap in semiconductor devices is developed to prevent electrical interference among the components.
Below, a non-volatile memory device is used as an example for description. In general, the conventional non-volatile memory device is formed of a stacked gate structure including a floating gate and a control gate formed of doped polysilicon. The floating gate is located between the control gate and the substrate and is in a floating state, while the control gate is connected with a word line. In addition, the non-volatile memory device further includes a tunneling dielectric layer and an inter-gate dielectric layer, which are respectively located between the substrate and the floating gate and between the floating gate and the control gate.
Due to the tendency of improving the integration of the devices, the size of the devices is reduced based on a design rule. Under such a circumstance, in order to prevent the increase of a resistor-capacitor (RC) delay and increase of a coupling interference between the floating gates to increase a gate coupling rate, an air gap is formed within the stacked gate structure to solve these issues.
However, as the integration of the device increases, the non-volatile memory device manufactured with the conventional method for manufacturing the non-volatile memory may have a lower air-gap ratio, and are thus unable to effectively reduce the RC delay and solve the issue of coupling interference between the floating gates.

Method for manufacturing structure having air gap


A method for issuing non-fungible tokens based on time-context data to be used for supporting transactions of historical time slots includes steps of: (a) an NFT platform server, in response to acquiring a specific intention, determining whether at least one specific issuance condition for at least one specific token corresponding to at least one specific historical time slot is satisfied; and (b) the NFT platform server, in response to determining that the specific issuance condition is satisfied, transmitting a specific transaction indicating that an issuance of the specific token is valid to at least part of nodes included in the blockchain network, to thereby update the nodes in the blockchain network and thus enable the issuance of the specific token corresponding to the specific historical time slot.

An NFT which stands for Non-Fungible Token is similar to cryptocurrency like a bitcoin in that it is also digital information recorded in a blockchain network. However, a characteristic of 'non-fungible', i.e., a characteristic of 'irreplaceable', is the main distinguishing feature between the two. In other words, for general cryptocurrencies such as the bitcoin, any amount is exchangeable given that it is of the same amount, since each individual coin does not have any differentiated feature. In contrast, the NFT, having characteristics of rarity and uniqueness, cannot be exchanged with each other.
By using such characteristics, the NFT is usually used for making transactions easier in fields where scarcity and uniqueness are important considerations such as art. However, usages of the NFT have several disadvantages, such as not being able to protect a copyright of an original author. That is, current NFT algorithms cannot prevent a person who is not the original author from obtaining undue profits by making and selling NFTs without a permission. Also, a purchase of the NFT does not necessarily guarantee an ownership of the purchased work but merely an obtainment of a proof of originality, therefore there are potential legal problems due to such discrepancies.
Therefore, it is preferable to use the NFT for purposes other than trading works of art. But, other than some usages in gaming, there appears to be no prominent usage in other fields.

Method for issuing and transacting non-fungible tokens based on time-context data to be used for supporting transactions of historical time slots, and server using the same