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ISRN Optics
Volume 2012, Article ID 151092, 3 pages
Plastic Deformation in Profile-Coated Elliptical KB Mirrors
1X-ray Science Division, Argonne National Laboratory, Argonne, IL 60439, USA
2National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
3Synchrotron Soleil, BP 48 Saint-Aubin, 91192 Gif-sur-Yvette, France
4Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
Received 19 July 2012; Accepted 8 August 2012
Academic Editors: K. Hane and S. R. Restaino
Copyright © 2012 Chian Liu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Profile coating has been successfully applied to produce elliptical Kirkpatrick-Baez (KB) mirrors using both cylindrical and flat Si substrates. Previously, focusing widths of 70 nm with 15-keV monochromatic and 80 nm with white beam were achieved using a flat Si substrate. Now, precision elliptical KB mirrors with sub-nm figure errors are produced with both Au and Pt coatings on flat substrates. Recent studies of bare Si-, Au-, and Pt-coated KB mirrors under prolonged synchrotron X-ray radiation and low-temperature vacuum annealing will be discussed in terms of film stress relaxation and Si plastic deformation.
1. Introduction
It has long been recognized that mirror figure can be modified by controlled thin-film deposition [1, 2]. We have developed a profile-coating technique to make ultraprecise elliptical mirrors for X-ray microfocusing [3, 4]. Elliptical KB mirrors with sub-nm figure errors can now be produced using flat Si substrates with only two profile coatings. Sub-100-nm focusing has been demonstrated using a synchrotron X-ray beamline [5]. Nested KB mirrors have also been successfully fabricated [6, 7]. One serious concern of X-ray mirrors is their long-term figure stability. We have noticed changes in mirror figure during prolonged X-ray irradiation when the mirror is too thin and narrow. The observed changes are believed to result from plastic deformation of profile-coated KB mirrors. This plastic deformation is a surprise since in our applications there is very little heat load on each KB mirror and the Si substrate has a brittle-ductile transition of 847°C [8].
The plastic deformation may be related to film stress introduced during coatings. The film stress can be relaxed at temperatures as low as a few hundred degrees C [9]. We found that low-temperature vacuum annealing can cause plastic deformation similar to that introduced by prolonged X-ray radiation in profile-coated KB mirrors. To overcome this plastic deformation, we need to optimize the mirror dimensions to improve mechanical stability and to decrease the film stress.
2. Recent Results of Au- and Pt-Coated KB Mirrors Using Flat Si Substrates
Precision elliptical KB mirrors with sub-nm figure errors have been fabricated with a predicted focal spot of 38.9 nm (FWHM), compared to the diffraction limit of 37.8 nm for a perfect ellipse [10]. On the 34-ID beamline at the Advanced Photon Source of Argonne National Laboratory, an Au-profile-coated KB pair, with dimensions of 70-mm L × 9-mm W × 4.5-mm H and 40-mm L × 10-mm W × 20-mm H, has produced ~0.60 × 0.40 μm2 focused white beams for several years under normal conditions until it was recently subjected to prolonged X-ray radiation continuously with the slits fully open for several days. After this exposure, the KB pair performance degraded so severely that it could no longer be used for microfocusing.
3. Extended Synchrotron Radiation and Low-Temperature Annealing Tests
One of the damaged mirrors, the 70 mm long one, was remeasured using microstitching interferometry. The mirror was coated with a uniform 15 nm thick Cr underlayer and an Au-profiled layer with thicknesses varying from 100 nm in the center to over 6 μm at the ends. The surface profiles before and after the extended X-ray radiation are shown in Figure 1(a). The profiles overlap with each other, but their height difference shows a clear upward, concaved profile change. The maximum deflection at the center of the mirror is ~140 nm. Another similar profile-coated KB mirror was annealed at 350°C for 15 min and measured before and after annealing, with results shown in Figure 1(b). An upward profile change is also evident after the annealing, with a maximum deflection of ~175 nm.
We repeated the same annealing procedure for a bare Si substrate, an Au- and a Pt-profile-coated mirror, with the same dimensions of 70-mm L × 9-mm W × 4.5-mm H. All samples were annealed three times with their surface profiles measured after each annealing and compared to that before each annealing. The maximum deflection results were plotted as shown in Figure 2. After the first annealing, they all had an upward concave profile change, with the Au-coated one changed the most. After the second annealing, the changes were all smaller. For Au-coated and bare Si, the profile change became convex. The third annealing had very little effect for all three samples.
4. Discussions
When flat substrates are used for profile coating of KB mirrors the film stress becomes a significant problem. For mirror application, an ultrasmooth, highly reflective coating is needed, which is often achieved using growth conditions with a low Ar pressure and a low substrate temperature. A large film stress is expected under these conditions [11] and will bend the substrate. For a wafer substrate the curvature change due to film stress is proportional to , where and are the film and the substrate thickness, respectively [12]. When the substrate is relatively thin and narrow, a film stress relaxation [11] can change the surface profile. A high film stress may also induce defect movements in the underlying Si at low activation energies, leading to plastic deformation in the substrate [13, 14]. The film stress relaxation is believed to be due to a diffusive relief of compressive stresses [9]. A film with a lower stress is expected to have a lower stress relaxation. Pt has a relatively smaller thermal expansion coefficient than Au and thus a smaller thermal stress, which may attribute to the observed differences in a smaller stress relaxation (Figure 2). The bare Si substrate also has a surface stress due to a compression of the surface layer during polishing [15, 16]. For chemical-mechanical polished substrates, the surface stress is relatively small and decreases rapidly with annealing. This smaller stress explains the smaller deflection for the bare Si substrate as shown in Figure 2.
The plastic deformation of the profile-coated KB mirrors under prolonged X-ray irradiation may also be due to film stress relaxation. It is known that the dominant absorption mechanism of the X-ray energy is photoionization in a thin surface layer [17]. This surface effect may be sufficient to cause a stress relaxation in the Au film without a noticeable increase in the mirror temperature. The surface photoionization under extended X-ray radiation may cause the same effect in the coated film as observed in low-temperature annealing. To make the mirror more stable, we need to use thicker substrates and decrease the film stress. One may choose coating materials with a smaller film stress, or coat only a strip on the mirror instead of coating the whole surface. Low-temperature annealing before the final corrective coating should also be helpful, even though the annealing temperature is limited by crystallization in the thick film. One may use spherical substrates so that less coating is needed. However, only a small region close to the center line can be coated precisely according to the design parameters due to the spherical shape of the substrate. In this case, a profile-figured substrate would be a much better choice. Currently, a profile-etching technique is under development to make such substrates using a broad beam ion source [18].
The authors would like to thank M. Wieczorek and J. Attig from Argonne National Laboratory for technical assistance. Work at Argonne was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract no. DE-AC02-06CH11357. G. E. Ice and J. Z. Tischler were supported by the DOE Office ofBasic Energy Sciences, Department of Materials Sciences and Engineering. R. Conley and C. M. Kewish were at Argonne and J. Z. Tischler was at Oak Ridge National Laboratory when this work was done.
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HONG KONG, May 02, 2016 (GLOBE NEWSWIRE) -- Sky Solar Holdings, Ltd. (Nasdaq:SKYS) ("Sky Solar" or the "Company"), a leading global developer, owner and operator of solar parks, today announced that the Company filed its annual report on Form 20-F for the fiscal year ended December 31, 2015 with the Securities and Exchange Commission on May 2, 2016.
The Company's annual report on Form 20-F contains its audited consolidated financial statements and is available on the Company's website at ir.skysolarholdings.com. The Company will provide a hard copy of its annual report free of charge to its shareholders and the holders of its American depositary shares upon request.
About Sky Solar Holdings, Ltd.
Sky Solar is a global independent power producer ("IPP") that develops, owns and operates solar parks and generates revenue primarily by selling electricity. Since its inception, Sky Solar has focused on the downstream solar market and has developed projects in Asia, South America, Europe, North America and Africa. The Company's broad geographic reach and established presence across key solar markets are significant differentiators that provide global opportunities and mitigate country-specific risks. Sky Solar aims to establish operations in select geographies with highly attractive solar radiation, regulatory environments, power pricing, land availability, financial access and overall power market trends. As a result of its focus on the downstream photovoltaic segment, Sky Solar is technology agnostic and is able to customize its solar parks based on local environmental and regulatory requirements. As of December 31, 2015, the Company had developed 273 solar parks with an aggregate capacity of 252.8 MW and owned and operated 128.6 MW of solar parks.
For Additional Information:
Investor Relations:
Victor Kuo
Phone: +86 (10) 6583-7526
Legal Statement

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It appears there is no normal season for farmers anymore.
After suffering through an extremely wet and cold winter last year, which pushed the planting season back because fields were too muddy, this year farmers are facing a new problem: warm, spring-like temperatures in January and February.
At least Jim Ellis, who has spent his entire life on the farm, said that was something new.
Address: 1025 Main St., Shelbyville.
There's a lot of construction going on in the back of the Hucks Store in Simpsonville, where the company has taken over space formerly housing Don Tequilla Restaurant for a significant store expansion.
The building, which is built within the shell of a 1920s edifice that for years housed gas stations and garages owned by Claude Moss and his family, in the next few months will become an estimated 3,000 to 4,000 square feet of retail space to update the store Hucks purchased in 2010.
Shelby engineering firm
wins state's highest honor
The American Council of Engineering Companies of Kentucky awarded Biagi, Chance, Cummins, London, Titzer, Inc. of Shelbyville with the Engineering Excellence 2012 Grand Award – its highest award – for its design of the University of Kentucky's Veterinary Diagnostic Laboratory (formally LDDC).
Contrary to popular belief, good enough can be as good as great.
Everywhere we look we hear powerful messages hammering on the importance of becoming great or successful. Whether it is in our work, parenting, marriage, or physical health, messages come at us from all directions telling us we need to do more to be more successful or better.
Obviously, there is nothing wrong with striving to live and work more productively. Many are able to achieve success in material terms, which is wonderful.
Photo submitted
Raymond J. Evans Jr. in front of the home of Paul David and Georgia Heightchew, which was raised, leveled and repaired after it had split into.
Address: 3244 Taylorsville Road, Shelbyville.
Kentucky unemployment fell
in 2011 but still trails nation
Kentucky's annual unemployment rate declined to 9.5 percent in 2011 from 10.2 percent in 2010, and nonfarm employment gained 21,200 jobs, according the Kentucky Education and Workforce Development Cabinet.
The U.S. annual unemployment rate fell to 8.9 percent in 2011 from 9.6 percent in 2010.
The newest tenant for the Kingbrook Industrial Park in Simpsonville is about ready for the trucks to start rolling in.
That's Brown Jordan International, an outdoor casual furniture company based in Louisville, and in about two weeks it will open in the building off Buck Creek Road that formerly was occupied by Kingbrook Window and Door.
"We're close – I think the move-in date is the second week in March," Brown Jordan President Chris Carmicle said via telephone from Mexico, where he was visiting one of the company's facilities. "We're excited about coming to town."
How much money will it take for you to retire in style? Will $1 million do the trick? How about $5 million? Or perhaps you can get by on less.
If the question leaves you scratching your head, you're not alone. Fewer than half of American workers have estimated how much they'll need to retire, according to the Employee Benefits Research Institute. The biggest risk retirees may face is running out of money while they're alive. It's an all-too-possible scenario, even if you have substantial assets.
If you watch TV or surf the Internet through cable, you have a new provider this week.
Time Warner Cable announced Wednesday that it had completed its acquisition of Insight Communications.
That means that Time Warner now will be the company that provides TV, high-speed Internet and voice services to about 760,000 customers throughout Kentucky, Ohio and Indiana – including those in Shelby County.
Copyright © 2019
The Sentinel-News is your source for local news, sports, events and information in Shelby County and Shelbyville, KY, and the surrounding area.


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Top communication tips for young professionals
Communication skills are a powerful arsenal that a young professional can use to overcome all odds. Learn to communicate using the right strategies for successful presentations, business meetings and during regular work. Read what experts have to say about the proper use of communication.
Communication skills are not limited to the usage of words and phrasing sentences to put your points across so your audience understands you. Communication skills encompass a lot more. They require a combination of words, actions and thoughts so you can dive into the subconscious minds of others.
Let me explain this through an example – Have you noticed how the most gripping commercials that grab the audiences' attention do not focus on specifications of the product that's been advertised. What companies market are not specifications, but the thrill, adventure and emotions. The advertisers capture a persona, a confidence, a mood or an attitude and present it to the audience. It is a tactic where marketing strategists make use of visual communication to attract the subconscious mind of a niche audience.
These powerful advertisements are intuitively more influential than any talk of specifications. The audience relates more to the emotions that these commercials generate – the product translates into a feeling rather than being just a specification. So, what is being marketed is not a commodity, but a whole new class concept – but what is being sold is actually a product. This is an example of perfect communication, which hits its target audience.
Communication at work
The main focus behind business communications is to get the attention of the customers, the clients and the consumers. If an analysis of the functioning of a successful organisation is done it is sure to highlight effective use of communication. Every successful launch of a product or a concept is a result of good communication, right from the birth of an idea, to development of a strategy, to the follow ups and the final execution of the initial idea, everything is centred on communication.
Yes, the action happens on the shop floors and manufacturing units, but it is an effect of communication. Concepts, strategies and actions are all linked through communication.
The right communication skills act as a tool that intuitively allows for the following actions –
Exactness of objectives
Good communication is about knowing where to start and where to end. Good communicators use each phase of their communication to get closer to the end they have in mind. There is a purpose behind their communications. If you bring in too much of baggage into your communications then the clarity of the objective is lost.
Good communicators make certain that their communications focus on one subject. Their conversations, their presentations and their emails cover individual issues. This ascertains that their messages are always understood.
To get better results stick to the core issues in your communication. Make the communication crisp and keep it to the point. Keep the language simple and understandable.
Recommended Reading : How to used non-verbal communication
Practical impact
Numbers, figures, data and facts when shared with others are generally ignored, especially during presentations. No one has the time or the will to analyse all the statistics to draw a conclusion. A good communicator weaves all the findings to create a story. The communicator correlates the data with the actual effects it can have/has on the business, inevitably creating a clearer picture of the whole scenario and thereby having a more tangible and persuasive effect on the audience.
Vivid visual communication
Communication is not just verbal and written, it can also be visual. It is, after all, an expression of thoughts and views, and there can be different modes of communicating the same. The introduction of graphics and media in presentations has opened a new vista for communication. Decisions and plans can effectively be communicated through graphic media. Even though there is a high reliance on technology, it is still a communication.
The audience can be better engaged through a graphic representation of your vision. For instance, a demonstration using visuals and animation of how the company's sales can surpass all previous sales by employing the proposed stratagem can be more useful than presenting adjusted data.
Effective communication
Communication whether on a personal level or business related must be effective. What is effective communication? Simply put it is the ability to transmit information in a convincing manner. The industry generally follows the KISS formula, which prescribes that you 'keep it simple, stupid'. This means no pomp and show, just get to the point. While this formula works sometimes, it is not effective all the time. At times you need to give it your all to make the desired impression.
Rewind a little to the point where I had mentioned advertisers using emotions to sell products. The same principle applies to you when you communicate with others. Humans are creatures of emotions – we have a tendency to associate with how things make us feel, rather than with specific details. So, providing mere facts about a service or a product would be less effective than creating an aura that ignites emotions. The audience is more likely to recall the sensations they feel/felt, better than the data. Putting up a show in your communications sometimes gets the desired results – the attention of the audience.
Impressions count
First impressions make a difference, especially when we communicate. The opening line when communicating, whether with a large audience or a small gathering or an individual should have the ability to grab attention. Entice the crowd with a smart quip so they look forward to your presentation, even before it begins to roll.
However, you must learn to alter your communication strategies based on who you will be presenting to. A presentation put up for a marketing team will be grossly different from one put up for a client. Communication is a very important tool and used effectively it can give your presentations the desired direction.
Customise your communications
Follow key communication principles for your business dealings and presentations and you'll never go wrong –


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Asterix At The Olympic Games
Release Date: 25 August 2008 | Certificate: Parental Guidance
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Alafolix (Stephane Rousseau) is a friend of Asterix (Clovis Cornillac) and Obelix (Gerard Depardieu) who has fallen deeply in love with the Greek Princess Irina (Vanessa Hessler). In order to win her hand in marriage Alafolix goes to Greece to compete in the Olympic Games. However magic potions have been banned at the Olympics and Alafolix Asterix and Obelix will have to use all their wits in order to defeat Cesars conniving son Brutus (Benoit Poelvoode).
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Release Date: 25 August 2008
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Firewall Security: Policies, Testing and Performance Evaluation
- Toby Johnston
- 3 years ago
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1 Firewall Security: Policies, Testing and Performance Evaluation Michael R. Lyu and Lorrien K. Y. Lau Department of Computer Science and Engineering The Chinese University of Hong Kong, Shatin, HK Abstract This paper explores the firewall security and performance relationship for distributed systems. Experiments are conducted to set firewall security into seven different levels and to quantify their performance impacts. These firewall security levels are formulated, designed, implemented, and tested phase by phase under an experimental environment in which all performed tests are evaluated and compared. Based on the test results, the impacts of the various firewall security levels on system performance with respect to transaction time and latency are measured and analyzed. It is interesting to note that the intuitive belief about security to performance, i.e. the more security would result in less performance, does not always hold in the firewall testing. The results reveal that the significant impact from enhanced security on performance could only be observed under some particular scenarios and thus their relationships are not necessarily inversely related. We also discuss the tradeoff between security and performance. 1. Introduction Nowadays, large and small companies are seeking ways of doing business on the Internet for global business. Meanwhile, Internet security issues become a hot topic. Companies accessing the Internet are seeking methods of protecting their network sites against external attacks and intrusion. Firewall is one of the best solutions. Setting up a firewall for private network sites in organizations and at home is no longer a too fancy thing. On the other aspect, performance impact may cause major concerns: Is there a significant performance loss while incorporating a secure environment using a firewall for the Internet connection? To what level of security should we expect without sacrificing the network performance? These are the basic questions asked when addressing the design of a secure network. Little research effort is made on this area before. This paper addresses the above queries by performing some security and performance testing on firewall of different security levels. The network security problems may be company security and network access policy problems. To create a realworld environment, a secured firewall system is set up by using the Linux TIS firewall packages with a router, and the objective is to compare the performance impact that a firewall system experiences when it is configured with different security policies and controls. Security and performance tests are designed for security verification and performance measurement under qualitatively different security levels. The firewall is configured into seven different security levels, phase by phase with their corresponding design and implementation. Experiments are conducted for firewall testing on the dedicated LAN, and empirical results are obtained regarding how the firewall performs under different policies of different security levels. Interesting observations about the tradeoff between security and performance are also described. 2. Methodology The experiments are performed in a security testing LAN in which a firewall is set up as the entry point for all the traffic going in and out of the LAN. Security and performance tests are conducted on the firewall. The firewall is configured with different security levels by using a router and several proxy servers. The details are described as follows Setting up Firewall Policies of Different Security Levels In order to determine the impact from different security controls on network performance, seven different firewall security policies are specified, so as to set up the firewall system for a project qualitative evaluation. The security levels defined in the paper are not based on any published class of security evaluation criteria such as the orange book [1]. However, lower security levels are theoretically and practically less secured than higher security levels. There are four basic components in building a firewall [1]: policy, advanced authentication, packet filtering, and application gateway. We specify a total of seven configurations and security levels of firewall, according to the requirements stated in the corresponding security
2 policies we defined theoretically. Security is considered higher for a higher level. The seven security policies are briefly described in Table 1. Table 1: Summary of the seven firewall security policies Security Policy and Level Main context of policy Deny any permitted Deny any permitted Deny any permitted 2.2. The Test Bed Proxy services installed? No No Other control None Disallow some problem service accesses from outside Ditto Ditto + Deny unauthorized and bad host accesses from outside Ditto Ditto + Restrict outside access to certain port number range only Ditto + Restrict internal access to some Internet services at outside hosts + deny access from hosts identified as intruder No. of screening rules set in the router To test the performance and security for the firewall policies, we establish a security test bed as shown in Figure 1 below. The test bed is consisted of a protected testing LAN of 10Mb throughput with a firewall connected to the Internet through a Cisco router. The firewall server is a PentiumBased PC with 32M RAM installed with Linux operating system and FWTK (Firewall Toolkit) package. The workstations used for the experiments are also running Linux. Users working at the PC communicate with the Internet through the firewall. Note that it is fairly common today to set up a firewall with a Linux box and a router for the protection of an internal network Figure 1: Test bed configuration for firewall testing 2.3. Security Testing Some security checkups and penetration testing are applied in testing the security of the firewall. Penetration test uses techniques designed to defeat and bypass security mechanisms in order to determine the effectiveness of such mechanisms for the network. As a matter of fact, it is difficult to simulate the real attackers behavior to the experimental LAN. However, the vulnerability of a specified firewall setup to certain intrusion or attacks could be checked with network scanning tools or some techniques which the intruders may use for hacking and attacking the firewall. Some scanning tools are used to simulate real network attacks and intrusions on the target system. When a security hole or warning was found in a particular test phase, it would be rectified or eliminated in the next test phase by adding some security controls such as screening rules to discard any questionable traffic. The 7 security levels are progressively defined and tested. The firewall in Level 7 is expected to be the most secured one Performance Testing Performance tests are done on the firewall to measure the relative performance degradation of two types of service, i.e. 'HTTP' and 'FTP' of the firewall. It simulates the real usage of the firewall by directing various loads of FTP and HTTP traffic through the firewall. The data transfer requests would be initiated inside the private network to an outside network server. The firewall performance is evaluated by the performance indicators of latency and total transaction time. Latency is the time required by a system to complete a single transaction from start to finish [4,5]. The data inspection at the firewall would lengthen the time required for data communication, as well as network or transaction latency. Experimentally, this indicator is
3 measured by executing a bunch of transactions sequentially in a single thread and the result is obtained by the taking the elapsed time used for processing each transaction [5]. The total transaction time, on the other hand, refers to the amount of time it takes to open one or more connections in a transaction from the client to the server and to request and download data from the server. Also it is assumed that the variables such as the available network bandwidth and stray noise on the network are consistent and would not create too much variance for most of the results Measurement Procedure FTP and HTTP test scenarios are designed for testing the firewall performance. During the experiments, the clients data download requests issued are passed to the firewall, which is responsible for communicating with outside and processing of data downloading requests. If no proxy service is adopted, the clients bypass the firewall and go directly to the outside network through Network Address Translation (NAT) done by IP Masquerader. Also FTP and HTTP requests could be initiated from clients to outside servers. This is the case when the firewall system is implemented with policies 1 and 2. On the other hand, if the firewall is incorporated with proxy services for data transfer, the FTP and HTTP requests are handled with additional traffic screening. This is the case with the firewall policies 3,4,5,6 and 7. The clients pass the FTP data transfer requests to the FTP proxy gateway running at the firewall and wait for the proxy server to pass the result back to them. As the proxy server becomes the middleman or agent between the service clients and the outside server, extra overhead for traffic handling occurs. Likewise, for HTTP data retrieval requests, the firewall server would act as the HTTP proxy server for all of the clients inside the firewall under the firewall policies 3 to 7. At least 10 trials for each test scenario are executed and 3 or more valid sets of data for each scenario are used for analysis. The starting and ending time in seconds are jotted down right before the data transfer is executed and after it finishes. The total average and minimum values of each transaction were used to calculate the final result of network latency under every firewall security level Experimental Design for HTTP and FTP Session Test Tests are carried out to transfer different amounts of data using HTTP and FTP protocols to see how the firewall performs under different policies. Some simple HTTP session scripts are written to perform HTTP GET protocol requests. The HTTP tests examine the environment of high volume but relatively small data size in a transaction. For FTP session test, bulk data of 5Mb data is attempted in scenario A. Scenario B involves a smaller data size of 1Mb. Besides, we examine the scenarios of low volume of data download and high volume of connections in test scenario C 2.7. Tools Description We employ SAINT [2] and Nessus [3,6] for host attack and scanning. For system security checking and monitoring, COPS [7] and BSB Monitor [8] are adopted. During the performance testing, a tool called "workload" [1,9] together with some shell scripts doing HTTP and FTP data transfers are adopted in synthesizing the desired traffic workload. 3. Analysis of Results 3.1. Security Testing The security testing are summarized in Table 2 below. Table 2: Security testing result in summary Security Level No. of warning and and Policy X vulnerability count(s) As expected that the security level (x + 1) is no less secured than the security level x based on the above results. The firewall setup for policies 4 and 5 is expected to be more or less the same with regards to the extent of security. But as policy 5 would deny everything by default whereas policy 4 would accept anything by default, so policy 5 is supposedly more secure than policy 4 even though the numbers of vulnerabilities found for them are similar. The testing is an attempt to quantify the difference of security between one security level and another. Furthermore, it helps in building up a secured firewall system from one level to another Performance Testing The average total transaction time and latency are found in different test scenarios under the 7 firewall security policies. The HTTP average total transaction time versus the number of connection is shown in Table 3 for tabular results and Figure 2 for graphical display. The
4 latency with the average total HTTP transaction time is shown in Table 4 and Figure 3. For the FTP performance testing, the latency calculated versus the number of connection in test scenario A is shown in Figure 4. Moreover, Figure 5 illustrates the performance test results with respect to the latency found in FTP test scenario B, while Figure 6 shows the performance test results derived in FTP test scenario C. Latency is calculated by the division of the "Total transaction time" with the "number of sequential transaction". Table 3: The average total HTTP transaction times in second A: No. of transaction B: No. of sequential connection A B 1x3 10x3 20x x3 100x3 Cfg Latency in second s x1 x10 x20 x30 x40 x50 x60 x70 x80 x90 x100 No. of transaction cfg4 Figure 3: The average HTTP latency vs the no. of connection under different firewall security levels Cfg Cfg Cfg Cfg Cfg Cfg Note: Cfg x refers to firewall configuration x with security level defined as Level x. TL transaction time in second s 2, , , , , , x1 x30 x60 x90 x120 x150 x180 x210 x240 x270 x300 x no. of connection(s) Figure 2: The HTTP total average transactions time vs the no. of connection Table 4: Latency calculated with average total HTTP transaction time in second Cfg X1 X10 X20 X 30 X 40 X 50 X X70 X80 X90 X100 Total Note: x1 means 1 transaction and 3x 1 connections; x20 means 3x20 connections and so on. Latency in second s x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 Avg No. of connection in a transaction Figure 4: Average latency (calculated with the average total transactions times) vs no. of connection for FTP 5Mb data transfer Latency in second in s Mx1 1Mx2 1Mx3 1Mx4 1Mx5 1Mx6 1Mx7 1Mx8 1Mx9 1Mx10 Size of data X no. of connection Figure 5: Average latency vs the no. of connection in a transaction for FTP 1Mb data cfg2
5 Latency in second s k x k x k x k x k x 40 Size of data (38.9K) x no. of connection(s) Figure 6: Average latency vs no. of connection request for FTP 38.9Kb data transfer 3.3. Analysis and Discussion As shown above, the performance result obtained from HTTP session test (Figures 2 and 3) is somewhat similar to that from test scenario C of FTP testing (Figures 6). The results from scenario A (Figure 4) and B (Figure 5) of FTP testing on firewall are more or less the same with respect to the overall firewall performance. Moreover, the firewall behaves very differently under particular security levels when comparing the results of FTP test scenarios A and B with that of test scenario C and the HTTP test. These interesting results provoke some thoughts on data traffic performance with different sizes and connection requests under different security controls and policies. The test results are discussed below. (a) HTTP session test In the testing of the highvolume connection and small data size file retrieval by using HTTP protocol, the data transfer times for the firewall policies 1, 2 and 3 differ significantly. When comparing the results of firewall security Level 2 with that of Level 3 in Figures 2 and 3, a remarkable increase of latency and processing time with security Level 3 is observed. But when proceeding from Level 3 to 4 or above, no obvious and consistent performance changes are concluded. Some key experimental observations are described below. Observation 1 Slight performance loss, but better security with security Level 2 As expected the firewall of the basic configuration (i.e. the lowest security Level 1) performs the best as shown in Figure 2. It is because no packetfiltering rule is set into the router and the router does very little work outside of routing traffic, so low overhead occurs for the security Level 1. Moreover, the tests show that security Level 2 performs slightly poorer than Level 1 in data transfer by using http protocol. This can be explained by the enhanced security control in Level 2. Cgf5 Observation 2 Significant Performance Degradation with Security Level 3 Furthermore, Figures 2 and 3 show a significant increase of processing time with security Level 3. In security Level 3, the proxy server imposes an overhead, which is comparatively significant to the total processing time and latency. The proxy process running at the firewall analyzes application commands inside data packets and keeps logs. Thus it incurs higher overhead than a simple packet filtering firewall, such as that in security Level 2. Moreover, for each new connection to the Internet, overhead from the proxy process happens. Thus if the number of connection is high the accumulated overhead would be enormous. Consequently, the time for HTTP transfer adds up quickly when the connection number is increased from 1 to 30 in security Level 3. Observation 3 Insignificant the performance impact among security Level 3 to 7 Interestingly, the curves of security Levels 3, 4, 5, 6 and 7 seem to be overlapped with each others, so whether there is a performance gain or loss among them is difficult to conclude. In fact, the firewall security Levels 3 to 7 are mainly implemented by a firewall technology of packet filtering, which is controlled by configuring different screening rules in the router. There is clearly a performance loss when security level proceeds from 1 to 2 and the number of screening rule is increased from 0 to 7. However, when further rules are added to the router, the performance difference is not obvious, even though when the number of screening rule is increased from 17 (Level 3) to 43 (Level 7). This phenomenon could be explained by the way the router parses the screening rules. Normally the router parses the rules in sequential order for a match. The speed of traffic going through the router depends very much on the sequence of rules set in the router. In other words, if the traffic is matched in the sequence of rules earlier, the faster the traffic goes through the router. When we look at the details of screening rules set in the router, the numbers of rule the router parses for FTP traffic under the implementation of firewall policies 3 to 7 are similar. As a result, the overall performance of policies 3 to 7 is very close to each other. Besides, the irregular shape of the performance curves for firewall policies 3 to 7 also suggests that their performance is easily affected by the environmental interference. (b) FTP session test As seen in the test results of scenarios A and B in Figures 4 and 5, the latencies of the 7 security levels do not differ from one another much in value. Similar to the HTTP testing, the latencies in scenario C are increased remarkably since the connection number is 5 or larger, and the latency of firewall configuration 3 is higher. Major observations are described as follows.
6 Observation 1 Low volume connection testing vs high volume connection testing As implemented in the experiment, 'lowvolume connection' means 1 to 10 connections, whereas 'highvolume connection' means 10 to 40 connection requests involved in data transfer. When considering the lowvolume connection testing, i.e., the scenario A and B in Figures 4 and 5, the difference of latencies among different security levels is not significant no matter whether the file size is 5M or 1M. For the highvolume connection testing with small data size, i.e., the test scenario C in Figure 6, the performance degrades when the firewall security level proceeds from 1, 2 to 3. Also the latency values found under the firewall Levels 3 to 7 are clearly larger than those under Level 1 and 2. This interesting result found in FTP test scenario C is similar to that found with HTTP protocol tests described previously. To sum up, if the number of connections to the Internet is high and the data size is small, the total accumulated overhead due to the proxy process becomes significant enough when it is compared with the total processing time without overhead. The usage of proxy servers for higher security at the firewall, as implemented in the firewall policies 3 to 7 in FTP test scenario C, would reduce the network performance. On the other hand, if the data size is large and the connection number to the Internet is small, the impact will be small, as seen in security policies 4 to 7. When the transaction time for each connection is comparatively longer, the time overhead added by proxy servers at the firewall becomes comparatively insignificant and unnoticeable. Observation 2 Insignificant performance difference among firewall policies 3 to 7 It is also clear that the performance difference among the firewall policies 3 to 7 is not large in the three FTP test scenarios. Just like the results obtained from HTTP tests, the fluctuations in their performance result curves appear very often in testing the three scenarios of data transfer with FTP protocol. The results imply that the performance difference among security levels due to the overhead of packet filtering for more security is negligible when compared with the outside traffic interference. 4. Conclusion In order to explore the security to performance relationship at firewall, we perform some experiments on a firewall system implemented with 7 proposed firewall policies. The performance of the firewall policies has been quantified and analyzed. In the security testing, the security levels are not only built up qualitatively with different security policies, but also tested and validated by using some network scanning tools. In the performance testing, for the scenarios of data transfer of small data size and high volume of HTTP or FTP connection requests, the firewall shows some performance difference under the implementation of different firewall policies. As seen from the overall testing results, the firewall performance is affected only if the overhead incurred by the enhanced security control is significant when compared with the normal transaction time without the enhanced security control. Performance degradation would not result unless the accumulated overhead incurred from the additional security mechanisms at the firewall outweighs the interference from outside traffic. Besides, it could be concluded that the intuitive belief about the security and performance relationship does not always hold. In other words, the same level of security at firewall could be achieved with different firewall technologies and resulted in different network performance. Therefore, the firewall technology is a major factor for performance evaluation. If frequent connections with data of small size are required in communication, enhanced firewall security would be very likely to bring out some significant performance degradation to the private network. This study enables us to design an optimal firewall technology that could implement a high security control in defending a private network, without incurring a significant performance loss. Acknowledgement The work described in this paper was supported by a grant from the Research Grant Council of the Hong Kong Special Administrative Region (Project No. CUHK4432/99E). References [1] M. Goncalves, "Firewalls", McGrawHill, [2] SAINT at the World Wide Digital Security Inc. [3] The Nessus Project, Renaud Deraison. [4] A. Molitor, "Measuring Firewall Performance", Network System Corporation. [5] C. Kostick and M. Mancuso, "Firewall Performance Analysis Report", August Computer Science Corporation CSC. [6] Vulnerabilities families of the Nessus Project. [7] COPS. [8] BSB Monitor. [9] WORKLOAD in the archives of the firewallperformance mailing list. ftp.greatcircle.com in /pub/firewallsperformance/digest/v01.n011.z.
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Certified McKenzie Clinics
Being a Certified McKenzie Clinic enables providers to brand and promote their practices as using the McKenzie Method. The McKenzie Institute International Faculty and Diploma holders throughout the world are permitted to make application for consideration by the Chief Executive Officer (CEO) to identify their existing clinic as a "Certified McKenzie Clinic." To this effect, a formal written application is made to the CEO outlining such request and confirming compliance with the following:
- The name "Certified McKenzie Clinic" cannot be registered or be exclusive to any one individual clinic.
- Active physiotherapy utilising the McKenzie Method of Mechanical Diagnosis and Therapy must be administered at the Certified McKenzie Clinic. At least one of the therapists in the Certified McKenzie Clinic must hold the qualification of Diploma in Mechanical Diagnosis and Therapy. That therapist must spend a minimum of 50% of their clinical practicing hours at that clinic. Accordingly, there can be no more than two clinics registered to any one Diplomaed MDT therapist. The clinic must have an educational policy and confirm in writing to the CEO that therapists employed within the clinic will be trained in the McKenzie Method, attending as a minimum Parts A to C of the Institute's Education Programme and, where possible, continuing through to the Credentialling or Diploma level.
- The Certified McKenzie Clinic must utilise the range of McKenzie products, i.e., TYOB, TYON and Original McKenzie Rolls, where appropriate.
- The Certified McKenzie Clinic must use the McKenzie assessment and treatment principles for all spinal and extremity patients, where appropriate.
- An annual fee of USD$200 will be payable to the International Office.
"Certified McKenzie Clinics" will be certified for a one year period: 1 April - 31 March in any given year, following which an application can be made to renew certification. Clinic certification and renewal of certification status will be subject to the clinic providing written confirmation that the requirements set out above continue to be met.
Certified McKenzie Clinics are eligible to be listed on the Institute's website. The Diplomaed therapist at the actual clinic must be the person listed within the Certified McKenzie Clinic Directory on the website.
Certified McKenzie Clinics will be authorised by the CEO to state on their letterhead that their clinic is a "Certified McKenzie Clinic," but they will not be permitted to use The McKenzie Institute International logo. A worldwide Register of Certified McKenzie Clinics is maintained by the International office.
Certified McKenzie Clinic DirectoryLooking for a Certified McKenzie Clinic? Search our global Clinic Directory


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An angel told Mary that she was going to have a baby from God.
When it was time for Mary to have her baby, she rode on a donkey to Bethlehem.
Out in the fields near Bethlehem were shepherds, watching their sheep in the night. Angels came to them and told them the Savior baby had been born.
Back in town, in a dirty stable, Jesus was born. He was full of God's perfect love.
With baby Jesus in that stable were a lot of animals.
The Christmas Star guided the wise men (or the Magi) to find Jesus.
The wise men traveled a long, long way to meet Jesus. We think they traveled on camels!
Together, Mary, Joseph, the shepherds and the wise men gathered and worshiped the baby king. We can worship Him, too.
Merry Christmas, Holy Yoga Kiddos!
Much love from your friends Rachel, Christina & Sarah


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We now offer a fun and interactive way to explore membership at Bridge Church – It's Starting Point Newcomers Party! Through Starting Point Newcomers Party you will learn what it means to belong to Bridge Church. This two-hour interactive party is designed to help you find out more about Bridge Church — Who we are, where we're headed, and how you can be a part.
Some of our pastoral team will walk you through our story, our core values, how to make an impact, and how to become a member at Bridge Church. Also during the party you will have a chance to win gift cards from Chick-Fil-A, Starbucks, Tropical Smoothie, and more.
"Starting Point was the perfect first step to becoming an Active Member of Bridge Church. From spending time with the Pastors, to learning about volunteer opportunities to serve, Starting Point helped me build a clear path in my Spiritual Journey." – Jared Fabac | Bridge Church Member
Starting Point Newcomers Party:
VA Beach: Monday, January 28, 2019 – 6:45 PM to 8:45 PM
Greenbrier: TBD
NOTE: Childcare and snacks are provided
Next Steps:: Click the appropriate button below to register for your party


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Boston's cobbled, windy streets are tough enough for bicyclers during the city's warm weather months, but sprinkle in some snow, and the already treacherous endeavor becomes that much more risky.
BostonBiker.org summed up the winter experience by saying "in the winter the sidewalks and bike paths become a hellish nightmare of ice and snow. It's really not worth it to even think about riding on them."
That means that the two options are to skip biking entirely and find another way of getting around, or risking life and limb in the bike or car lanes.
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"This speaks to priorities of the city," Ken Carlson, chair of the Somerville Bike Committee told Metro."Minneapolis is the number two city in the country to bike and they get far more snow than we do. It would be nice to have more proactive cleaning of bike lanes from the city. Last year, bike lanes were non-existent. They basically disappear during snowy conditions and the days and weeks after."
According to the Boston Cyclist Safety Report, most of the bike accidents occur during the warmer months, and tend to be bike versus vehicle incidents. Between 2010 and 2012, most of the collisions took place in "favorable weather." But the number of people willing to bike also declines during the winter.
Experts and advocates have a laid out suggestions and strategies for those brave enough to try their luck on the pothole-riddled, slush-covered, black ice-laden roads. Having the proper brakes, tires and handling skills make the difference between getting to a destination versus wiping out.
Related: Pregnant teen dies after shoveling
"The bike lanes often aren't cleared as well as the car lanes,"said Becca Wolfson of the Boston Cyclist Union. "Bikers have to be ready to take the car lanes, which means they need to be extra vigilant. The brakes aren't there to stop you, they're there to slow you down, so it's a lot safer to go slower during the winter months."
Other small details, like checking if your brakes are frozen before riding, riding in a straight line, and sitting on the seat to keep a lower center of gravity are common suggestions meant to ensure rider safety. Taking the time to practice riding in winter conditions on weekends and during the non-rush hour hours also helps familiarize bikers with navigating black ice, potholes and other obstacles.
"Potholes are probably the biggest concern," Wolfson said. "They have the potential to do the most damage. Luckily, the city is pretty good at responding to reports of potholes through their 311 program and the SeeClickFix app."
Both Wolfson and Carlson said that the bridges over the Charles River are the most hazardous routes they and their fellow riders encounter.
"Crossing the Charles River on the Mass Ave bridge or the Longfellow Bridge are critical conduits of biker traffic and those are places that need a lot of attention," Carlson said.
"The Mass Ave bridge was pretty much never clear last year," Wolfson said. "It's a tight squeeze and can be overwhelming, but it is doable if you are prepared."


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Jean-Eric Vergne will have to dig into his own pockets after Valencia. The rookie Frenchman was given a ten-position grid drop for Silverstone after oddly jinking before crashing into Caterham's Hei...
The rookie Frenchman was given a ten-position grid drop for Silverstone after oddly jinking before crashing into Caterham's Heikki Kovalainen on Sunday and then speeding back to the pits with a disintegrating Toro Rosso.
The incident caused the race director to call a safety car period, whilst stewards ruled that a EUR 25,000 fine was also in order for Vergne due to "the serious nature" of the indiscretion.
"What he did was not acceptable and it was his fault," former Toro Rosso team co-owner Gerhard Berger told Austrian Servus TV on Wednesday.
Christian Horner, the boss of Red Bull's senior team, said it is likely 22-year-old Vergne will have to pay the fine himself.
"If it's the driver's fault, he has to pay the money," the Briton, who works closely with Vergne's boss Dr Helmut Marko, said.
"But if, for example, a driver is too fast in the pitlane because his limiter is not working properly, then probably the team will pay the fine.
"Jean-Eric will probably have to reach into his own pockets for this one," added Horner.
The French publication Business Book GP 2012 lists Vergne's estimated 2012 salary at EUR 400,000.


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Financial Intermediation and Equity Investment with Costly Monitoring
Di Giorgio, Giorgio (1999) Financial Intermediation and Equity Investment with Costly Monitoring. [Working Paper]. p. 18. Economics Working Papers (No. 410).
PDF (Full text)
Download (58kB)
Official URL: http://www.econ.upf.edu/docs/papers/downloads/410....
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This paper studies the efficiency of equilibria in a productive OLG economy where the process of financial intermediation is characterized by costly state verification. Both competitive equilibria and Constrained Pareto Optimal allocations are characterized. It is shown that market outcomes can be socially inefficient, even when a weaker notion than Pareto optimality is considered.
|Item Type:
|Report / Paper (Working Paper)
|Research documents and activity classification:
|Working Papers > Non-Refereed Working Papers / of national relevance only
|Department of Business and Management
|Additional Information:
|The latest version of this paper has been published in "International Review of Economics & Finance", Elsevier, vol. 11(1), pages 27-43, April 2002
|Uncontrolled Keywords:
|Financial Intermediation, Costly State Verification, Constrained Pareto Optimality
|MIUR Scientific Area:
|Area 13 - Economics and Statistics > SECS-P/01 Political Economy
|Deposited by:
|Maria Teresa Nisticò
|Date Deposited:
|23 Nov 2010 08:10
|Last Modified:
|21 Apr 2015 23:13
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Sunday, 28 August 2011
Tirupati Darshan by walking through the 7 Hills...
7 comments:
Good to go through your experience of visiting Balaji Mandir. I feel the Q system is mismanaged totally. Usually with computer tagging Sheegra dharsan should take max 1 hour, sudharshan dharsan 2 hours and general 3 hours. We find there is no difference in Sheegra dharasan and free darshan of late. The entry too is not regulated at all.ReplyDelete
Hey Puneet.......... nice to hear you had a nice experience..........good write up.........ReplyDelete
TIRUPATI TIRUMALA LORD BALAJI DARSHAN / SEVA / ADVANCE BOOKING / INTERNET BOOKING DETAILS CONTACT email@example.com FOR COMPLETE INFORMATION AND LATEST UPDATES, UR COMPLETE TIRUPATI DARSHAN GUIDE.ReplyDelete
Is there any special line for persons came on foot..ReplyDelete
Should take any darshanam tickets..
- Anonymous17 May 2015 at 06:43
I also had very good darshan recently.ReplyDelete
Thanks for whay you shared.may.lord blesss all of us.
Thanks for sharing information about Tirupati Balaji Temple. Located just 4 hours away from Bnagalore city, Tirupati (Thirupathi) boasts of being the location of one of the most affluent temples of India. Also, check out other tourist place near Bangalore and plan your vacation.ReplyDelete
Excellent info. We planned based on your details. Have recorded our trip here https://oursimplejourneys.wordpress.com/2015/11/15/tirumala-by-foot-a-trip-diary/ReplyDelete


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Establishing an emergency fund is essential for creating a strong foundation for your finances. Without some savings, even the smallest emergency will leave you in dire straits.
You will want to have about 1 month of living expenses in this fund before you do almost anything else financially. If you are just starting out, it is impossible to be prepared for everything, so you may have to rely on help from your parents or take credit card loans if something really big comes up. As you continue to save and work on your finances, you will become more and more able to absorb small emergencies without having to worry about where the money is going to come from.
Gradually you will build you emergency fund up to either 6 months of expenses, or however large you feel comfortable with. The goal is that should you become unexpectedly unemployed or encounter an emergency expense you will not have to sweat it. One good rule of thumb is to save enough to carry you through however long you believe you may reasonably be unemployed if you lose your job. On average this may be about 6 to 8 months, but it may be longer or shorter depending on your individual situation.
Your emergency funds must be accessible within a few days, but need not be instantly available. Most of the time, you will have at least a couple of days to come up with the money. For immediate payment, you can use credit cards or perhaps take a short term loan from a friend. It is often be better if your emergency savings are not immediately available they are not so you won't be tempted to spend these funds. This also typically allows you to earn a better interest rate.
Emergency funds should be held in a separate savings account and not intermingled with funds for other purposes. You don't want to spend these funds on anything that is not a true emergency, so a separate account will keep your accounting 100% accurate.
An online bank will work well for this purpose because they pay higher interest rates, and the instant availability of a bank branch is unnecessary for these funds. If you need the funds, you simply send an electronic funds transfer to your checking account or to pay off your credit card.
By establishing an emergency fund, you stabilize your finances and minimize the financial pain caused by life's unexpected events. If you take this important financial step, you will sleep better at night, and be better able to cope with emergencies if and when they occur.


text: Today i will probally send off for 2 airport extreme cards. I cannot afford the basestation yet (have to wait untill next month when i have the money). But i was wondering if it is possible to share files with both the machines even though i do not have the base station?


text:
Alternative Titles
English: Love You Only
Synonyms: ラブユーオンリー
Japanese: ラブユーオンリー
Type: Manga
Volumes: 1
Chapters: 5
Status: Finished
Published: Mar 2000
Genres: Yaoi
Authors: Agawa, Kouko (Story & Art)
Serialization: None
Score: 6.561 (scored by 121 users)
1 indicates a weighted score. Please note that 'Not yet published' titles are excluded.
Ranked: N/A2
2 based on the top manga page. Please note that 'R18+' titles are excluded.
Popularity: #19093
Members: 213
Favorites: 1


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No – you're panicking that there's only 2 weeks left until Christmas.
Every year I tell myself that I'm going to be more organised and that I'm going to all the Christmas shopping done before the 1st December. I never ever do and this year is no exception, and it's even harder with looming wedding invoices slowly building up and the most expensive time of year. I struggle with Christmas presents; it's a mix of wanting to not just spend money for the sake of spending it and not knowing what to get. But, ther'es one thing I'm really good at buying for; dogs and their dog obsessed humans.
So, here's what you will find in both mine and Rufus' Christmas stockings this year


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Wedding Fayre Cancelled
Published Wed 15th February, 2012 by Loughborough Town Hall
The Wedding Fayre due to take place at Loughborough Town Hall on 26 February has been cancelled at short notice by the fayre promoter Pickled Ginger.
"We are very disappointed with Pickled Ginger's decision," said Town Hall Manager Nigel Strong. "The company had hired our venue for the fayre and we had fulfilled all our contractual obligations in support of the event. With just 12 days notice they have decided to cancel without giving any satisfactory explanation. This is extremely frustrating, as now there is not enough time available to put in place any alternative arrangements which might have enabled the Fayre to take place. Loughborough Town Hall would like to apologise unreservedly to our customers, stall holders and suppliers for any disappointment, but unfortunately the situation has been beyond the venue's control."
Last Updated, Mon 27th February 17:34


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We offer tailored content, making it easier to find what you're looking for. If you're unsure, contact the UQ Student Centre for more information.
To be eligible for admission to a UQ program, you need to satisfy all entry requirements. These include:
Some programs have limited places available and competition for admission is high. It is possible that you may meet minimum entry requirements, but not be offered a place.
Completing Queensland Year 12 (or equivalent) is a basic requirement for most undergraduate programs.
Prerequisites are the assumed knowledge requirements for a program. At a minimum, these are usually Queensland Year 12 authority subjects, or interstate or international equivalents.
You must successfully complete a program's prerequisites to be considered for admission. If you're interested in completing a dual program, you must satisfy the subject prerequisites for both programs.
Some programs also have recommended (non-compulsory) knowledge areas. We make these recommendations to ensure you are in the best possible position to understand program material.
If you are not currently studying Year 12 (or equivalent), your application will be assessed to determine whether you have successfully studied the required prerequisites.
Once you have completed Queensland Year 12 (or equivalent) and satisfied a program's prerequisites, the next thing you need to do is achieve a minimum entry score for admission.
If you're currently studying Year 12 (or equivalent) in Australia or New Zealand, you must achieve the required OP, QLD Rank or ATAR score for your preferred UQ program.
If you're currently completing your senior schooling overseas, you must achieve the minimum international entry score (PDF, 355KB) for your preferred UQ program.
If you aren't a current school leaver, your application will be considered on an individual basis.
We can consider any study you have completed after high school. If you are eligible for entry, you may also be able to apply for admission with credit.
International students must demonstrate English-language proficiency for admission. The minimum standards for proficiency are:
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Learn more about English language requirements
Some programs use more than subject prerequisites and entry scores.
The Bachelor of Music (Honours), for example, asks applicants to audition.
Please carefully check each program you are interested in studying for specific application requirements. These will be listed under "Program Details".
If you're currently studying Year 12 (either in Australia or offshore) or the International Baccalaureate (IB) in Australia, submit your application online through the Queensland Tertiary Admissions Centre (QTAC).Apply to QTAC
If you're an international student not currently studying Year 12 or the International Baccalaureate (IB) in Australia, submit your application directly to UQ.
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