• Journal of Institute of Control, Robotics and Systems
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• v.5 no.8
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• pp.889-897
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• 1999

This paper deals with a problem searching a target transfer function to meet the time-domain specifications for feedback system with given plant transfer function. For the Type I system, we first define three forms of transient response to unit step input, which are named by F, M, S-type. These are charaacterized as follows ; F-type has fast initial response and slow approach to the steady sate after reaching at 90% of the steady state value, S-type has slow initial response but fast approach to the steady state, and M-type is denoted by highly smooth response between F-type and S-type. Three prototypes corresponding to each form are proposed, time. For the order $n{\geq}4$, after determining admissible root structures of target characteristic polynomials empirically and expressing such polynomial coefficients by using special parameters ${\gamma}_i$ and $\epsilon$, the optimal prototypes that minimize the integral of the squared of the modified errors(ISME) have been obtained. Since the step responses of these prototypes have almost same wave forms irrespective to the order, the desired settling time or the rise time can be converted into the equibalent time constant $\tau$ and thus it is easy to obtain a target transfer function. It is shown through a design example that the present prototype is very useful for meeting the time-domain specifications and has been compared with different methods with a viewpoint of pertinence.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.27 no.1
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• pp.313-336
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• 2016

The study reviews theoretical and empirical research literature in information needs, seeking and uses in order to search for the most pertinent metatheories for studying information practices of the disadvantaged. The study examines the salient features and main theories/models of each cognitive, affective and social approach in the user-centered paradigm through analyzing prior information practices studies. While analyzing the main features of each cognitive, affective and social approach, the study points out the limitation of research using the cognitive and affective approaches to fail to theorize the relationship between individuals and complex and dynamic socio-cultural contexts in information practices. As an alternative, the study suggests using the social approach as a pertinent metatheory for understanding information practices of the disadvantaged who are entangled with myriad social contexts and issues. In order to verify the pertinence, the study examines the advantages of the social approach through analyzing both the main models related to everyday information practices under social constructionism and the main findings from information practices of the disadvantaged.

• Journal of Periodontal and Implant Science
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• v.34 no.1
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• pp.35-48
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• 2004

Since the occlusal loading is transmitted to the surrounding bone, the success of an implant treatment is closely related to the distribution of the stress on the implant. The finite element analysis method is often used in order to produce a model for dispersion of stress. Assessment of the success of the implant is usually based on the degree of osseointegration which is a bone and implant surface interface. Implant used in this research was designed through the method of shape optimization after the stress on implant was anaylzed by the finite element analysis method. This study was pertinently assessed by a clinical, histologic, histomorphometric analysis after the shape optimized implant was installed on beagle dog tibia. The results are as follows 1. It clinically showed a good result without mobility and imflammatory reaction. 2. Implant was supported by dense bone and bone remodeling showed on the surrounding area of the implant 3. The average percentage of bone-implant contact was 58.1%.The percentage of bone density was 57.6%. Having above results, shape optimized implant showed the pertinence through clinical and histologic aspects. However, to use the shape optimized implant, the further experiment is required for finding problems, improvement.

• Journal of Korean Medical classics
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• v.21 no.2
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• pp.113-124
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• 2008

The main characteristic of 'Idea of Uimul(宜物思想)' lies in specifically laying down rules on the subject of thought, and creating correlated measures and ways based on those grounds. Thus, 'Ui(宜)' emphasizes the pertinence of the measures and ways. By making a detailed analysis, the importance of 'Mul(物)', the subject of thought, the perception of it, the human reaction to it, and the specific principle of the action, can be seen. Ancient Chinese considered Heaven and Earth the largest frame of perception, and perceived all things through it. Heaven and Earth was differentiated from 'Gi'(氣), and the Gi of Heaven and the Gi of Earth interacted with one another in endless motion. "Hwangjenaegyeong(黃帝內經)" considered nature and all things in it through this ideology of 'Correspondence between Heaven and Humanity(天人相應)'. It considered humans to be born from the Gi of Heaven and Earth and to associate with one another under the influence of the Gi of Heaven and Earth. Therefore, in "Hwangjenaegyeong(黃帝內經)", the ideology of 'Correspondence between Heaven and Humanity(天人相應)' is the fundamental frame of Idea of Uimul(宜物思想). On the other hand, the Ui(宜) in Idea of Uimul(宜物思想) indicates the pertinent measures and ways towards a subject, that is, humans acting appropriately according to the laws of Heaven and Earth inside the ideology of 'Correspondence between Heaven and Humanity(天人相應)'. Humans are affected by nature and adapt to it, but they also recognize the laws of nature and strive to wholly protect the human life by versatilely taking adequate measures against the numerous changes of nature.

• The Journal of the Korea Contents Association
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• v.10 no.1
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• pp.334-342
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• 2010

The purpose of this study was to evaluate web-sites related to infant health at day-care centers. A total of 87 web-sites were ultimately selected through Internet search engines, and educare sites. The basis of assessment in which standards and items were amended for the assessment of health information in previously used, and purpose, content, pertinence, accuracy, confidence, utility, authority, interactivity and continuance was assessed. Though the total score were 32 point, mean score was relatively low, 20.39 point. The score of accuracy and authority was relatively low while that of confidence and interactivity was high. As a result, it was revealed that there were no specific infant health related web-site with reliability guaranteed. Therefore, there is a need to develop a web-site providing accurate health information for infant at day-care centers. It is expected that these results can be utilized as a data for developing reliable web-site related infant health.

• Journal of the Korea Convergence Society
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• v.9 no.3
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• pp.61-71
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• 2018

The research analysis will be proceeded with a specific question: The kind of endeavors the ICT providers must focus on within the ICT industry's Schumpeterian pattern of using barriers of knowledge during the rapid technological transformation and pursuing appropriability of guaranteed opportunities. The study was carried out by targeting and conducting empirical observations on the proliferation of technological patent applications made by ICT companies among approximately 5,700 listed North American corporations. The risk of arising cases, in which late-coming non-ICT companies adopt and participate in the technical pertinence and concept derived from the technological advent, will be treated as an independent variable in a survival analysis. Through this analysis, innovative technological attempts and absorption capabilities indicate significance.

• Journal of the Korean Society for Library and Information Science
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• v.8
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• pp.73-101
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• 1981

Retrieval effectiveness is the principal criterion for measuring the performance of an information retrieval system. The effectiveness of a retrieval system depends primarily on the extent to which it can retrieve wanted documents without retrieving unwanted ones. So, ultimately, effectiveness is a function of the relevant and nonrelevant documents retrieved. Consequently, 'relevance' of information to the user's request has become one of the most fundamental concept encountered in the theory of information retrieval. Although there is at present no consensus as to how this notion should be defined, relevance has been widely used as a meaningful quantity and an adequate criterion for measures of the evaluation of retrieval effectiveness. The recall and precision among various parameters based on the 'two-by-two' table (or, contingency table) were major considerations in this paper, because it is assumed that recall and precision are sufficient for the measurement of effectiveness. Accordingly, different concepts of 'relevance' and 'pertinence' of documents to user requests and their proper usages were investigated even though the two terms have unfortunately been used rather loosely in the literature. In addition, a number of variables affecting the recall and precision values were discussed. Some conclusions derived from this study are as follows: Any notion of retrieval effectiveness is based on 'relevance' which itself is extremely difficult to define. Recall and precision are valuable concepts in the study of any information retrieval system. They are, however, not the only criteria by which a system may be judged. The recall-precision curve represents the average performance of any given system, and this may vary quite considerably in particular situations. Therefore, it is possible to some extent to vary the indexing policy, the indexing policy, the indexing language, or the search methodology to improve the performance of the system in terms of recall and precision. The 'inverse relationship' between average recall and precision could be accepted as the 'fundamental law of retrieval', and it should certainly be used as an aid to evaluation. Finally, there is a limit to the performance(in terms of effectiveness) achievable by an information retrieval system. That is : "Perfect retrieval is impossible."

• Clinical and Experimental Emergency Medicine
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• v.5 no.4
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• pp.264-271
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• 2018

Objective For patients with acute myocardial infarction (AMI), symptoms assessed by emergency medical services (EMS) providers have a critical role in prehospital treatment decisions. The purpose of this study was to evaluate the diagnostic accuracy of EMS provider-assessed cardiac symptoms of AMI. Methods Patients transported by EMS to 4 study hospitals from 2008 to 2012 were included. Using EMS and administrative emergency department databases, patients were stratified according to the presence of EMS-assessed cardiac symptoms and emergency department diagnosis of AMI. Cardiac symptoms were defined as chest pain, dyspnea, palpitations, and syncope. Disproportionate stratified sampling was used, and medical records of sampled patients were reviewed to identify an actual diagnosis of AMI. Using inverse probability weighting, verification bias-corrected diagnostic performance was estimated. Results Overall, 92,353 patients were enrolled in the study. Of these, 13,971 (15.1%) complained of cardiac symptoms to EMS providers. A total of 775 patients were sampled for hospital record review. The sensitivity, specificity, positive predictive value, and negative predictive value of EMS provider-assessed cardiac symptoms for the final diagnosis of AMI was 73.3% (95% confidence interval [CI], 70.8 to 75.7), 85.3% (95% CI, 85.3 to 85.4), 3.9% (95% CI, 3.6 to 4.2), and 99.7% (95% CI, 99.7 to 99.8), respectively. Conclusion We found that EMS provider-assessed cardiac symptoms had moderate sensitivity and high specificity for diagnosis of AMI. EMS policymakers can use these data to evaluate the pertinence of specific prehospital treatment of AMI.

• Advances in aircraft and spacecraft science
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• v.10 no.3
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• pp.223-243
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• 2023

There is a burgeoning demand for minimizing the mass of satellites because of its direct impact on reducing launch-to-orbit cost. This must be done without compromising the structure's efficiency. The present paper introduces a relatively low-cost and easily implementable approach for optimizing structural mass to a maximum natural frequency. The natural frequencies of the satellite are of utmost pertinence to the application requirements, as the sensitive electronic instrumentation and onboard computers should not be affected by the vibrations of the satellite structure. This methodology is applied to a realistic model of Al-Azhar University micro-satellite in partnership with the Egyptian Space Agency. The procedure used in structural design can be summarized in two steps. The first step is to select the most favorable primary structural configuration among several different candidate variants. The nominated variant is selected as the one scoring maximum relative dynamic stiffness. The second step is to use perforation patterns reduce the overall mass of structural elements in the selected variant without changing the weight. The results of the presented procedure demonstrate that the mass reduction percentage was found to be 39% when compared to the unperforated configuration that had the same plate thickness. The findings of this study challenge the commonly accepted notion that isogrid perforations are the most effective means of achieving the goal of reducing mass while maintaining stiffness. Rather, the study highlights the potential benefits of exploring a wider range of perforation unit cells during the design process. The study revealed that rectangular perforation patterns had the lowest efficiency in terms of modal stiffness, while triangular patterns resulted in the highest efficiency. These results suggest that there may be significant gains to be made by considering a broader range of perforation shapes and configurations in the design of lightweight structures.

• Nuclear Engineering and Technology
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• v.56 no.2
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• pp.389-401
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• 2024

In recent decades, numerous instances of blockages have been reported in coastal nuclear power plants globally, leading to serious safety accidents such as power reduction, manual or automatic power loss, or shutdown of nuclear power units. Loss or shortage of cooling water may compromise the reliability of the cooling water system, thus threatening the operational safety of power plants and resulting in revenue reduction. This study provides a comprehensive review of the current state of cooling water system safety in coastal nuclear power plants worldwide and the common challenges they face, as well as the relevant research on cooling water system safety issues. The research overview and progress in investigation methods, outbreak mechanisms, prevention and control measures, and practical cases of blockages were summarized. Despite existing research, there are still many shortcomings regarding the pertinence, comprehensiveness and prospects of related research, and many problems urgently need to be solved. The most fundamental concern involves understanding the list of potential risks of blockages and their spatially distributed effects in surrounding waters. Furthermore, knowledge of the biological cycles and ecological habits of key organisms is essential for implementing risk prevention and control and for building a scientific and effective monitoring system.