The torsion test was evaluated as a method for determining the shear strength of full-size structural lumber. The evaluation involved an experimental length study, an experimental depth study, and a finite element study. The length study consisted of fifty nominal 2x4 specimens, ten specimens for each length, and ten American Society for Testing and Materials (ASTM) shear blocks. One 14 foot long board yielded one specimen for each length: (a) 21.0", (b) 28.5", (c) 32.0", (d) 35.5", (e) 39.0", and (f) an ASTM D143-94 shear block. The statistical analysis revealed no evidence that the length affected the shear strength. The depth study consisted of fifty specimens, ten specimens for each depth: (a) 2x4, (b) 2x6, (c) 2x8, (d) 2x10, and (e) 2x12. In addition, fifty ASTM shear blocks, one block for each specimen, were tested. The statistical study did not reveal convincing evidence of a depth effect on shear strength, even after accounting for specific gravity and shear span as covariates. Failure modes for the torsion samples involved a longitudinal shear crack at the mid-point of the longest side, which propagated toward the ends of the specimen and through the cross section perpendicular to the growth rings. The finite element model revealed that uniform shear stress occurs within the shear span, which begins and ends a distance of approximately two times the depth plus the grip distance away from each end of the member. In addition, torsion theory verified that the experimental shear failure plane that occurs within the shear span is parallel to the grain and the shear slippage is also parallel to the grain, similar to the known shear failure in specimens subjected to bending loads. Based on the results of this study, the torsion test is the best practical method to determine the pure shear strength of full-size structural lumber, because the test yields 100% shear failures and the specimen is in a state of pure shear stress. / Graduation date: 1998

In 1987, Congress authorized a 5 year $150 million dollar research program called the Strategic Highway Research Program (SHRP). SHRP was divided into four major areas, including the asphalt research program. The asphalt research program was divided into six major research contracts, one such contract, SHRP-003A was called Performance Related Testing and Measuring of Asphalt Aggregate Interaction and Mixtures. Oregon State University performed the portion of this contract related to the development and validation of accelerated test procedures for aging, low temperature cracking, and moisture sensitivity of asphalt-aggreagte mixtures. This thesis contains five independent papers that discuss elements of the development, validation, and or implementation of these accelerated test procedures. In the first paper, the relationship between field performance and laboratory aging properties of asphalt-aggregate mixtures is discussed, including the relative importance of asphalt binder and aggregate type on the amount of aging experience. Based on this work recommended aging procedures are presented to simulate different environmental conditions and pavement age. The second paper makes use of the large body of resilient modulus data conducted as part of the SHRP research effort to compare data obtain in the diametral and the triaxial mode. It is not possible to give a relationship between triaxial and diametral resilient modulus, without describing specimen geometry and other test conditions. The third paper discusses the effect of aging on the thermal cracking properties of asphalt-aggregate mixtures. The temperature at which aging occurs affects the way cold temperature fracture properties change with time. Low temperatures result in quenching of the aging process, while high temperatures result in continued aging. The fourth paper discusses work conducted in association with the Oregon Department of Transportation to extend the environmental conditioning system (ECS) test procedure for moisture assessment to open graded mixtures. Comparison in the ECS of mixtures with and without anti-strip agents added indicates that they don't always decrease moisture damage potential. The final paper presents a discussion of asphalt chemistry and its relationship to asphalt-aggregate mixture performance. Using the SHRP asphalt model, aging and low temperature performance data collected at Oregon State University is explained. / Graduation date: 1995

This thesis covers two topics. The first subject involves tests run on a ultralite reflux tube supplied by Battelle Pacific Northwest Laboratories (PNL). The second topic involves tests to determine the relative wicking rates of several different fabrics. The ultralite reflux tube supplied by PNL was constructed of copper and Nextel 312. It had a 10 mil thick copper evaporator and a 10 mil thick copper condenser end cap. The bulk of the condenser was 2 mil thick copper covered by a one inch diameter Nextel 312 woven hose. A life test was run within the Heat Pipe Test Facility, a chamber used to simulate low earth orbit. The life test lasted for over 800 hours, during which time the reflux tube operated steadily with no drop in performance. At the end of the test the reflux tube was removed and observed. The only noticeable change was a slight discoloration of the Nextel 312 used to cover the condenser. This discoloration was consistent with previously observed phenomenon. The second topic, fabric wicking rate studies were done as a follow up study to the dry uptake tests previously conducted at Oregon State University. The purpose of the tests were to get a relative feel for the ability of different fabrics to wick water. This was achieved using a drop test in which the fabrics were laid out on a bridge connecting two containers. One of the containers was elevated above the other. The fabrics were allowed to wick water from the upper container to the lower container and the rate at which this was accomplished was measured. The fabrics were all able to move significant amounts of water. The stiffer fabrics seemed to perform better. The major transport mechanism was transport between fabric layers and the fabric and the bridge. / Graduation date: 1993

The development of software today, the company has their own test system usually. Because there has a few bugs in the every software. And it will make the damage of company¡¦s property or security of information. We can find the bugs in the software by the test systems. But the few bugs will appear repeatedly even if you have been fixed it. In this time, it will be effective if we use the automatic test systems. They can solve the waste of time and cost. Appearance of the automatic test system has been solved the defect of the test method in the past. In this paper will mention two kind of automatic test systems, one of them is concolic testing, and another is random testing. In the 2009, there had the few of evidence to discuss that the concolic testing was more effective than the random testing, but there wasn¡¦t have the enough demonstration. So I hope to prove that the effectiveness comparison between concolic and random testing by this paper.

In recent year, a lot of scholar try to generate test sets for combinatorial strategy automatically. But these algorithms based on combinatorial strategy don¡¦t consider conflicts of input parameter model. A conflict exists when the result of combining two or more values of different parameter dose not make sense. Thus, invalid sub-combinations may be included in test cases in the test suite, and these are useless to us. Besides, these algorithms all directly generate all test cases once, in other words, it is unable to utilize test cases generated at present to feedback and revise the algorithm, so it is easy to generate useless combinations. So, this paper proposes new test generation algorithm for combinatorial testing based on constraint satisfaction problem(CSP) to solve problem which invalid sub-combinations may be included in test cases, and we can add constraints flexibly during generating test cases to avoid generate useless or repeated combinations. The experimental result indicate that our algorithm perform well, with respect to the amount of time required for test generation, otherwise, we can generate conflict-free test cases directly.

In recent year the research field of the combinatorial testing, which can roughlybe divided into two kinds including pair-wise coverage and multi-wise coverage. a lot of scholar try to use various strategies to generate test data automatically. In order to weight the generated test set, the generated test data must satisfy certain criterion. But these combinatorial strategy neglected the flexibility of using on the practice. Considering software testing from the practice, which often be restricted by the cost. For this reason, how to obtaint the greatest testing benefits under the limited cost must be considered on the parctice. But in the extant combinatorial strategy, there is no flexible use. In other words, we must testing test set totally. Therefore, there is very great restriction to exist on using the test data generated by the extant combinatorial strategy on the practice. So, this paper proposes a flexible combinatorial strategy based on CSP, which allow users to do the most valid testing under the limited cost, which also allow users join the constraints that needs at any time during the testing process, revise the test data that we produced dynamically. The experimental result indicate that our method perform well, it can avoid including the test data whether some users think the interests less or unnecessarier, in order to achive the greatest testing beneifts.Further, we can achive the goal of reducing the quantity of testing data.

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