• ETRI Journal
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• 제20권4호
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• pp.346-360
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• 1998

It is challenging to parallelize problems with irregular computation and communication. In this paper, we propose an asynchronous algorithm for balancing unpredictable workload on distributed-memory machines. By using an initial workload estimate, we first partition the computations such that the workload is distributed evenly across the processors. In addition, we perform task migrations dynamically for adapting to the evolving workload. To demonstrate the usefulness of our load balancing strategy, we conducted experiments on an IBM SP2 and a Cray T3D. Experimental results show that our task migration strategy can balance unpredictable workload with little overhead. Our code using C and MPI is portable onto other distributed-memory machines.

• 산업경영시스템학회지
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• 제22권50호
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• pp.139-149
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• 1999

The objective of this study was to evaluate the effects of normal veiling reflection on the human visibility during visual tasks. The apparent task luminance and the apparent background luminance contrast were determined by the levels of the normal veiling reflection luminance and the interior illuminance of the visual target. The semantic differential methodology was used for the ergonomic evaluation of the conditions of experiment which were consisted of the apparent task luminance and the apparent background luminance contrast. Twelve subjects (6 male and 6 female) were participated in this study to perform the tasks which were consisted of 40 experimental conditions. And each condition was repeated 4 times.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1997년도 추계학술대회논문집
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• pp.437-440
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• 1997

The association of poor body postures with pains or symptoms of musculoskeletal discorders has been reported by many researchers. An ergonomic evaluation of postural stresses as well as biomechanical stresses is also important especially when a job involves highly repetitive or prolonged poor body postures. The human body is divided into five parts: shoulder/upper arm, lower arm/wrist, back, neck, lower extremities. A work-sampling based macropostural classification system was developed to characterize various postures in this study. Application of the posture classification schema developed in this study to 7 automobile assembly tasks showed that the schema can be used as a tool to didntify the operation and tasks involving highly stressful body postures. This posture classification schema can also be applied as a basis for quantitive evaluating the workload of manual task.

• 한국학교보건학회지
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• 제24권2호
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• pp.141-154
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• 2011

Purpose: The purpose is to provide basic information for establishing improvements on performance-based pay's evaluation method of health teachers. Methods: For subjects, 200 teachers at public elementary schools and 200 health teachers at public elementary schools in Gyeonggi-do were conveniently sampled, and then surveyed through a questionnaire. The questionnaire was to recognize recognition of teachers working under the teacher's performance-based pay system, which was quoted in the questionnaire of Choi ji-hye (2005) and Lee mi-gyeong (2008). Inquiry for the recognition of teachers on evaluation of health teacher's performance-based pay system and improvements on the performance-based pay's evaluation method of health teachers were used after consultation with five incumbent health teachers and a review with the thesis director. Results: The performance-based pay's evaluation method of health teachers has the same method with general teachers in schools, so it is not fair to evaluate the performance of health teachers. The ways to improve the performance-based pay evaluation method of health teachers is as follows: first, the approval on improving 'the number of class hours' which is a detailed item of a teacher's performance evaluation criterion to 'the number of health lesson hours per week and the number of students visiting the school infirmary per week'; second, improving 'life guidance' into 'counseling results of medically-treated students, parents of students and personal hygiene guidance'; third, improving 'a teacher in charge' into 'awarding of points by being recognized as a health teacher in charge of all students and considering the economic situation of the region,; forth, improving 'difficulty of position' into 'the number of health-teacher's annual promotion task items and the treatment number of issuing and receiving of official documents', and improving the 'task difficulty' into 'importance and urgency of emergency patient management, risk level and urgency of infectious diseases and avoiding work in charge' appeared to be more than 90% respectively. Conclusion: The performance-based pay system of teachers being carried out every year should be executed by preparing fair evaluation criteria suitable for task properties and the role of health teachers with different evaluation criteria compared to general teachers.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 추계학술발표회요약집
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• pp.117.1-117
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• 1999

• 수산해양교육연구
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• 제27권1호
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• pp.125-132
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• 2015

The purpose of this study was to search the concept and meaning of performance assessment(PA) in the classroom, and the to proposed some strategies to apply PA. The result of this study was presented below. First, differentiation strategy is necessary in the evaluation goal. Individualization will be an example of differentiation strategy in the evaluation of group goal. Second, various strategies are needed based on the subjects of evaluation. Self-evaluation, peer-evaluation, and small group-evaluation are some examples evaluation for the subjects. Third, there is a need for phase-strategy assessment. For the class associated performance assessment, we have to consider the evaluation activities based on the time likes before (pre), on, and after class. How to select the evaluation task is also one of the key sucess factors for improving the class associated performance assessment.

• 과학교육연구지
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• 제37권1호
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• pp.170-185
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• 2013

본 연구의 목적은 생물 분류 탐구에서 과제 집착의 인지적인 모형을 규명하는 것이다. 이를 위해 생명 과학 탐구에서 과제 집착에 대한 다양한 문헌들을 분석하여 과제 집착에 대한 가설적인 인지적 모형을 고안하였다. 이 후, 고안한 모형의 규명을 위해 과제 집착의 분석을 위한 과제를 개발하고 사고 발성법과 회상적 면접법을 이용하여 연구 참여자의 프로토콜을 수집, 분석함으로써 생물 분류 탐구에서 과제 집착의 인지적 모형을 규명하였다. 연구 결과, 문헌 기반의 모형을 고안하고 프로토콜 분석을 통하여 규명한 과제 집착의 인지적 모형을 크게 과제 집착 유발, 과제 집착 강화, 과제 집착 유지의 세 단계의 과정으로 구성하였다. 과제 집착 유발 단계에서는 과제에 대한 관찰, 과제 관련 경험 표상, 탐구 예비 수행, 목표 평가의 하위과정으로 구성하였다. 과제 집착 강화 단계는 경험 기반 탐구 계획 설정 또는 경험 미기반 탐구 계획 설정, 적극적인 수행 및 소극적인 수행, 탐구 수행중 자기 평가, 가설 검증까지 반복적인 수행의 하위 과정으로 구성하였다. 과제 집착 유지 단계에서는 완료 후 피드백 수행, 자발적인 후속 탐구 수행의 하위 과정으로 구성하였다. 각 단계마다 과제 집착 구성 요소인 자신감, 목표설정, 주의집중이 변화하는 것으로 구성하였다. 위 연구 결과에 의해 생물 분류 탐구에서 과제 집착의 인지적 모형을 통해 생물 분류 탐구에서 과제 집착 향상을 위한 구체적인 교수-학습 전략을 구성하기 위한 기초 정보를 제공할 수 있으며 탐구과정에서 과제 집착의 단계적인 평가와 피드백 제시에 도움이 될 것이다.

• 감성과학
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• 제12권3호
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• pp.279-288
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• 2009

이 연구의 목적은 과제수행에 대하여 주관적 인지부하 요인과 GSR의 각성수준이 어떤 관계를 형성하고 있는지를 검증하는 것이다. 이를 위하여 인지부하 설문지(신체적 노력, 정신적 노력, 지각된 과제난이도, 자기평가, 자료설계의 용이성), 사전-사후검사, GSR에 의한 각성수준을 측정하였다. 사전검사는 학습자의 사전지식 수준을 의미하며, 사후검사는 과제수행의 결과를 의미한다. 이 연구의 분석방법은 사후검사의 결과를 종속변수로 하는 회귀분석이었다. 첫째, 자기보고의 인지부하 요인이 사후검사에 미치는 영향을 분석한 결과에 따르면, 사전검사, 신체적 노력, 지각된 과제난이도가 사후검사에 유의미한 영향을 미치고 있었다. 신체적 노력은 정적관련성을 보이고 있었으나 지각된 과제난이도는 부적관련성을 보이고 있었다. 이 결과는 사전검사의 점수가 높은 사람은 상대적으로 과제난이도를 낮게 지각하는 경향이 있으며 과제해결을 위하여 신중히 노력함으로써 사후검사의 결과가 올라간다는 것을 보여주는 것이다. 둘째, 각성수준에 대한 연구결과에서는 평가단계에서 측정된 각성수준이 사후검사의 점수를 유의미하게 예측하고 있는 것으로 나타났다. 평가단계의 GSR은 과제수행(사후검사)과 부적 관계를 형성하고 있었다. 즉, 평가단계에서 적절한 이완수준을 유지하고 있을 때 사후검사의 결과가 증진된다는 것을 보여주는 것이다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권6호
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• pp.3046-3070
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• 2017

Nowadays, the utilization of multiprocessor environments has been increased due to the increase in time complexity of application programs and decrease in hardware costs. In such architectures during the compilation step, each program is decomposed into the smaller and maybe dependent segments so-called tasks. Precedence constraints, required execution times of the tasks, and communication costs among them are modeled using a directed acyclic graph (DAG) named task-graph. All the tasks in the task-graph must be assigned to a predefined number of processors in such a way that the precedence constraints are preserved, and the program's completion time is minimized, and this is an NP-hard problem from the time-complexity point of view. The results obtained by different approaches are dominated by two major factors; first, which order of tasks should be selected (sequence subproblem), and second, how the selected sequence should be assigned to the processors (assigning subproblem). In this paper, a hybrid proposed approach has been presented, in which two different artificial ant colonies cooperate to solve the multiprocessor task-scheduling problem; one colony to tackle the sequence subproblem, and another to cope with assigning subproblem. The utilization of background knowledge about the problem (different priority measurements of the tasks) has made the proposed approach very robust and efficient. 125 different task-graphs with various shape parameters such as size, communication-to-computation ratio and parallelism have been utilized for a comprehensive evaluation of the proposed approach, and the results show its superiority versus the other conventional methods from the performance point of view.

• Asian Pacific Journal of Cancer Prevention
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• 제17권2호
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• pp.835-838
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• 2016

Background: Lung cancer remains one of the most common cancers in the world, both in terms of new cases (about 13% of total per year) and deaths (nearly one cancer death in five), because of the high case fatality. Errors in lung cancer type or malignant growth determination lead to degraded treatment efficacy, because anticancer strategy depends on tumor morphology. Materials and Methods: We have made an attempt to evaluate effectiveness of machine learning algorithms in the task of lung cancer classification based on gene expression levels. We processed four publicly available data sets. The Dana-Farber Cancer Institute data set contains 203 samples and the task was to classify four cancer types and sound tissue samples. With the University of Michigan data set of 96 samples, the task was to execute a binary classification of adenocarcinoma and non-neoplastic tissues. The University of Toronto data set contains 39 samples and the task was to detect recurrence, while with the Brigham and Women's Hospital data set of 181 samples it was to make a binary classification of malignant pleural mesothelioma and adenocarcinoma. We used the k-nearest neighbor algorithm (k=1, k=5, k=10), naive Bayes classifier with assumption of both a normal distribution of attributes and a distribution through histograms, support vector machine and C4.5 decision tree. Effectiveness of machine learning algorithms was evaluated with the Matthews correlation coefficient. Results: The support vector machine method showed best results among data sets from the Dana-Farber Cancer Institute and Brigham and Women's Hospital. All algorithms with the exception of the C4.5 decision tree showed maximum potential effectiveness in the University of Michigan data set. However, the C4.5 decision tree showed best results for the University of Toronto data set. Conclusions: Machine learning algorithms can be used for lung cancer morphology classification and similar tasks based on gene expression level evaluation.