• Korean Journal of English Language and Linguistics
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• v.3 no.4
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• pp.571-588
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• 2003

The purpose of this study is to investigate into the various ways that the computer technology is used for language testing. Three uses of computer technology are mentioned: 1) computer-adaptive language testing and computer-based language testing, 2) the scoring of performance-based language assessment, and 3) the development and use of psychometric tools for analyzing the scoring results. Although the various uses of computer technology could provide expanded possibilities for language testing development, the developers should be reminded that they are currently subject to indepth research which could support their validity. In this regard, the advantages and limitations of some uses of computer technology for language testing are discussed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.6
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• pp.2139-2151
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• 2014

Embedded system testing, especially long-term reliability testing, of flash memory solutions such as embedded multi-media card, secure digital card and solid-state drive involves strategic decision making related to test sample size to achieve high test coverage. The test sample size is the number of flash memory devices used in a test. Earlier, there were physical limitations on the testing period and the number of test devices that could be used. Hence, decisions regarding the sample size depended on the experience of human testers owing to the absence of well-defined standards. Moreover, a lack of understanding of the importance of the sample size resulted in field defects due to unexpected user scenarios. In worst cases, users finally detected these defects after several years. In this paper, we propose that a large number of potential field defects can be detected if an adequately large test sample size is used to target weak features during long-term reliability testing of flash memory solutions. In general, a larger test sample size yields better results. However, owing to the limited availability of physical resources, there is a limit on the test sample size that can be used. In this paper, we address this problem by proposing a self-adaptive reliability testing scheme to decide the sample size for effective long-term reliability testing.

• Journal of Digital Convergence
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• v.4 no.1
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• pp.43-54
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• 2006

New technologies have turned theories of education engineering into practice and also made education more efficient. One of them is the theory of 'Computer Adaptive Testing(CAT)'. This study is aimed to design and develop a web-based teaming system by making up for the weak points in the existing computer adaptive testing(CAT). The characteristics of the system are as follows: Firstly, tests can be controlled to fit the teachers' purposes by putting in different levels of both questions and samples. Secondly, this system does not test the same number of questions as students with different levels of ability do on a paper test, but a test can be taken according to their level. Thus this system is able to correctly judge learners' ability in a short time.

• Journal of Information Processing Systems
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• v.13 no.4
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• pp.703-715
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• 2017

Mammogram images are sensitive in nature and even a minor change in the environment affects the quality of the images. Due to the lack of expert radiologists, it is difficult to interpret the mammogram images. In this paper an algorithm is proposed for a computer-aided diagnosis system, which is based on the wavelet based adaptive sigmoid function. The cascade feed-forward back propagation technique has been used for training and testing purposes. Due to the poor contrast in digital mammogram images it is difficult to process the images directly. Thus, the images were first processed using the wavelet based adaptive sigmoid function and then the suspicious regions were selected to extract the features. A combination of texture features and gray-level co-occurrence matrix features were extracted and used for training and testing purposes. The system was trained with 150 images, while a total 100 mammogram images were used for testing. A classification accuracy of more than 95% was obtained with our proposed method.

• Physical Therapy Korea
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• v.20 no.4
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• pp.22-31
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• 2013

The aim of the present study was to compare measurement precisions of the Oswestry Back Pain Disability Questionnaire (ODQ) and a computer adaptive testing (CAT) method. The ODQ has been regarded as one of the most reliable condition-specific measure for back pain for decades. Cross-sectional study was carried out with two independent convenient samples from two out-patient rehabilitation clinics for back pain ($n_1=42$) and non-back pain group ($n_2=42$). Participants were asked to fill out the ODQ and CAT of International Classification of Functioning, Disability and Health-Activity Measure (ICF-AM). A series of Rasch analyses were performed to calculate person ability measures. The CAT measures had greater relative precision in discriminating the groups than did the ODQ measure in comparisons of the relative precision. The CAT measure appears to be more effective than did the ODQ measure in terms of measurement precision. By administering test items calibrated in a way, CAT measures using item response theory may promise a means with measurement precision as well as efficiency.

• Physical Therapy Korea
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• v.26 no.3
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• pp.106-114
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• 2019

Background: It is difficult to assess whether community-dwelling frail older adults may remain pre-frail status or improve into a robust state without being directly checked by health care professionals. The health information perceived by older adults is considered to be one of best sources of potential concerns in older adult population. An online measurement system combined with item response theory (IRT) and computer adaptive testing (CAT) methods is likely to become a realistic approach to remotely monitor physical activity status of frail older adults. Objects: This article suggests an approach to provide a precise and efficient means of measuring physical activity levels of community-dwelling frail older adults. Methods: Article reviews were reviewed and summarized. Results: In comparison to the classical test theory (CTT), the IRT method is empirically aimed to focus on the psychometric properties of individual test items in lieu of the test as a whole. These properties allow creating a large item pool that can capture the broad range of physical activity levels. The CAT method administers test items by an algorithm that select items matched to the physical activity levels of the older adults. Conclusion: An online measurement system combined with these two methods would allow adequate physical activity measurement that may be useful to remotely monitor the activity level of community-dwelling frail older adults.

• Journal of Korea Multimedia Society
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• v.5 no.6
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• pp.638-645
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• 2002

One of the potential advantages of computer-based instruction is individualization of instruction. However, this goal has not been fully realized in practice, due largely to limitations of natural language understanding and to combinatorial explosion. It is nonetheless possible to develop CAT(Computer- based Adaptive Testing) Programs which can adapt to students, depending on their performance, by adjusting the length of computer-based tests. The number of questions can be significantly reduced for many individuals, while mastery and nonmastery decisions remain highly accurate. In this paper, We design and implement a Diagnosis System using SPRT(Sequential Probability Ratio Testing). This system supports multimedia object, client/server environment, indvidual feedback, multi-SPRT and maintain student model for individualization of instruction. besides, this system measures coefficient alpha of each problem.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.12
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• pp.1447-1457
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• 1999

본 논문에서는 일반적인 네트워크에서 적응력 있는(adaptive) 분산형 시스템 레벨 결함 진단을 위한 분할 기법을 제안한다. 적응력 있는 분산형 시스템 레벨 결함 진단 기법에서는 시스템의 형상이 변경될 때마다 시험 할당 알고리즘이 수행되므로 적응력 없는 결함 진단 기법에 비하여 결함 감지를 위한 시험의 갯수를 줄일 수 있다. 기존의 시험 할당 알고리즘들은 전체 시스템을 대상으로 하는 비분할(non-partitioning) 방식을 이용하였는데, 이 기법은 불필요한 과다한 메시지를 생성한다. 본 논문에서는 전체 시스템을 이중 연결 요소(biconnected component) 단위로 분할한 후, 시험 할당은 각 이중 연결 요소 내에서 수행한다. 이중 연결 요소의 관절점(articulation point)의 특성을 이용하여 각 시험 할당에 필요한 노드의 수를 줄임으로서, 비분할 기법들에 비해 초기 시험 할당에 필요한 메시지의 수를 감소시켰다. 또한 결함이 발생한 경우나 복구가 완료된 경우의 시험 재 할당은 직접 영향을 받는 이중 연결 요소내로 국지화(localize) 시켰다. 본 논문의 시스템 레벨 결함 진단 기법의 정확성을 증명하였으며, 기존 비분할 방식의 시스템 레벨 결함 진단 기법과의 성능 분석을 수행하였다.Abstract We propose an adaptive distributed system-level diagnosis using partitioning method in arbitrary network topologies. In an adaptive distributed system-level diagnosis, testing assignment algorithm is performed whenever the system configuration is changed to reduce the number of tests in the system. Existing testing assignment algorithms adopt a non-partitioning approach covering the whole system, so they incur unnecessary extra message traffic and time. In our method, the whole system is partitioned into biconnected components, and testing assignment is performed within each biconnected component. By exploiting the property of an articulation point of a biconnected component, initial testing assignment of our method performs better than non-partitioning approach by reducing the number of nodes involved in testing assignment. It also localizes the testing reassignment caused by system reconfiguration within the related biconnected components. We show that our system-level diagnosis method is correct and analyze the performance of our method compared with the previous non-partitioning ones.

• The Journal of Korean Association of Computer Education
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• v.4 no.2
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• pp.21-29
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• 2001

The purpose of this study is to design and implementation of the Web-based Individual Computerized Adaptive Testing(CAT) system. The Web-based Individual CAT is a kind of test system to present a set of the problems divided into basic level, intermediate level and advanced level according to the saved results after doing a diagnostic test related to each unit. The diagnostic test is done to pull out the necessary items which learners have to study. The strong points of the web-based computerized adaptive testing system are to reduce the problems of distributed teachers and to have the effect of individual learning by using this system.

• The Journal of Korean Association of Computer Education
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• v.9 no.2
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• pp.69-78
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• 2006

Educational evaluation is not the work to rank learners hierarchically, but the thing to increase the educational effectiveness by solving a learner's problem and improving the education process from the proper evaluation. The conventional evaluation systems have measured a learner's recognition level by dichotomy. Although they support the evaluation depending on a learner's academic ability and supply the feedback for wrong selection, it is insufficient to take out study-motive and give the establishment for a guidance point of learning. In this paper, we propose the web-based individual adaptive testing system in considering partial score for a learner. Our system are effective to estimate the ability of learner by considering partial score in detail and offer an feedback study from the self-diagnosis function for a learning results.