The intersection of decreasing resource size and increasing population and its associated demand creates a pressing need to develop products that act as alternatives to solid sawn lumber. Engineered composite lumber is one such alternative. The product described herein utilizes a modified form of sawn lumber as the raw material. The objective of this research was to manufacture, mechanically test, and evaluate a novel type of engineered lumber. Non destructive evaluation of raw materials and finished beams, and final mechanical testing to determine mean strength and stiffness values as per ASTM 5456 were used. The mechanical property data was converted into design values for fiber stress in bending (Fb) and stiffness (MOE). These design values was compared to those published by the U.S. (NDS) for wood construction. Pine logs were reduced into cants and further processed into matched symmetrical trapezoids. Symmetrical trapezoids were then non-destructively evaluated via E-computer and Director, and sorted by results. Next, the sorted trapezoids were matched into pairs and assembled into bowtie beams. Polyvinyl acetate adhesive was used throughout. Stiffness of the manufactured beams was nondestructively evaluated too. Then the beams were mechanically tested. The information from the E-computer was correlated to the strength and stiffness for each beam. The design strength and stiffness was compared to the values of sections of equivalent depth and maximum width as shown in the NDS. Also, non destructive test values were compared and correlated to those from the destructive tests. Finally, the design strength and stiffness values were respectively multiplied by the sectional area or the moment of inertia. This produced a strength efficiency factor and a stiffness efficiency factor. These factors were compared to factors derived from multiplying the design strength or design stiffness values (from the NDS) times the area or the moment of inertia of a rectangular section of equivalent depth and maximum width. It is found that the mechanically efficient bowtie section produced an increased strength and stiffness efficiency as compared to that of solid sawn material.

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IRT, also referred as "modern test theory", offers many advantages over CTT-based methods in test development. Specifically, an IRT information function has the capability to build a test that has the desired precision of measurement for any defined proficiency scale when a sufficient number of test items are available. This feature is extremely useful when the information is used for decision making, for instance, whether an examinee attain certain mastery level. Computerized adaptive testing (CAT) is one of the many examples using IRT information functions in test construction. The purposes of this study were as follows: (1) to examine the consequences of improving the test quality through the addition of more discriminating items with different item formats; (2) to examine the effect of having a test where its difficulty does not align with the ability level of the intended population; (3) to investigate the change in decision consistency and decision accuracy; and (4) to understand changes in expected information when test quality is either improved or degraded, using both empirical and simulated data. Main findings from the study were as follows: (1) increasing the discriminating power of any types of items generally increased the level of information; however, sometimes it could bring adverse effect to the extreme ends of the ability continuum; (2) it was important to have more items that were targeted at the population of interest, otherwise, no matter how good the quality of the items may be, they were of less value in test development when they were not targeted to the distribution of candidate ability or at the cutscores; (3) decision consistency (DC), Kappa statistic, and decision accuracy (DA) increased with better quality items; (4) DC and Kappa were negatively affected when difficulty of the test did not match with the ability of the intended population; however, the effect was less severe if the test was easier than needed; (5) tests with more better quality items lowered false positive (FP) and false negative (FN) rate at the cutscores; (6) when test difficulty did not match with the ability of the target examinees, in general, both FP and FN rates increased; (7) polytomous items tended to yield more information than dichotomously scored items, regardless of the discriminating parameter and difficulty of the item; and (8) the more score categories an item had, the more information it could provide. Findings from this thesis should help testing agencies and practitioners to have better understanding of the item parameters on item and test information functions. This understanding is crucial for the improvement of the item bank quality and ultimately on how to build better tests that could provide more accurate proficiency classifications. However, at the same time, item writers should be conscientious about the fact that the item information function is merely a statistical tool for building a good test, other criteria should also be considered, for example, content balancing and content validity.

This work aims at giving a systematic review of the numerical approaches and obtained results published in recent years. Focus is set on both the recent trends and achievements as well as challenges and open questions. Thesis critically reviews work done in previous thesis related to food packaging material and design, at Blekinge Institute of Technology with the collaboration of Tetra Pak liquid food packaging company. Here, 27 numbers of master’s thesis are critical review all the while using 4 PHD works for referencing.  Focus of these thesis works relates to the mechanics and its sub-branch fracture mechanics. Due to this all the theory related to mechanics and fracture mechanics, which is compulsory to know for understanding is defined initially. Main material which are under consideration throughout the work are PP, LDPE, PET-LDPE, and aluminum foil. As three materials are used in the liquid food packaging which are PE, paper board and aluminum. Uses of this material and there required physical properties are measured. Testing methods which are used to check whether the material meets the required parameters are tensile testing, tear testing, peel testing and shear test.  Also, some methods are used along with these tests to perform the test more precisely, to evaluate and compare result i.e., Nakajima test, Digital image correlation. DIC testing technique is used to compare the results obtained from simulation. It is also understood that DIC method provided the user with increased quality of obtained results.  Most of the topics of discussions have been reviewed for corresponding thesis, displaying the used ideas, theory, applied experimentation and realized conclusions. Using these above it was able to derive a conclusion based on the developed research questions and hypothesis. Defined problems in previous work are studied also solution as a future work is suggested to overcome these problems. Mainly the slippage issue while holding PE in clamps. Furthermore, various development is discussed which is done to introduce new material which is more possible being used in the future.

Context: Testing is an important activity in software development and is typically estimated to account for nearly half of the efforts in the software development cycle. This puts a great demand on improving the artifacts involved in this task such as the test cases and test suites (a collection of test cases).  Objective: When executing test programs, it is typical to record runtime information associated with the test cases in the form of test execution logs or traces. The aim of this work is to explore how this information can be utilized to improve the software testing process. To this end, two main aspects are investigated which are (1) in the context of test case generation and (2) in the context of different optimizations regarding existing test suites. Furthermore, the role of the logs regarding fault localization in connection with improving the existing test suites is investigated. Method: A systematic literature review is conducted to investigate, identify and analyze the existing literature on test case generation and test suite optimization that utilizes the test execution logs. Results: After a rigorous search in six digital databases, 26 primary studies were identified. 5 of the selected papers propose approaches in the context of test data generation, 8 papers suggest test case prioritization (TCP) techniques, 4 papers discuss approaches in test case selection (TCS), and 5 papers propose approaches in test suite minimization (TSM). Furthermore, we identified, 3 papers that discuss fault localization, and one paper that discussed the decomposition of large test cases into smaller single purpose test cases using the logs from previous test executions. Conclusion: The test execution logs are a useful source of information for different testing activities. Regarding test case generation, the main theme observed is the use of genetic algorithms in attempting to generate appropriate test cases when the alternative might have been to use random test data generation methods. When it comes to improving existing test suites several approaches within TCP, TCS and TSM such as similarity-based, modification-based, cluster-based, and search-based were put forward by the authors of the selected primary studies. Furthermore, several fault localization techniques using the logs were suggested.

Research on prejudice has long been skewed by participants’ ability to monitor their reactions on overt measures of such attitudes. Accordingly, researchers created an implicit measure to study prejudice (Greenwald & Banaji, 1995). The Implicit Association Test (IAT) was thus developed. Though the IAT has long been purported as the only ‘true’ measure of participants’ feelings and cognitions, recent research has suggested the measure is not as infallible as once purported (e.g., Smith & Zarate, 1990). The purpose of this study was to integrate existing research on exemplars and how they affect scores on the IAT. Results showed that priming participants with racial exemplars that vary in terms of stereotypicality and valence had little effect on Race-IAT scores. Further, contrary to previous research, significant differences between African American and European American participants on the Race-IAT did emerge.

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