• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.6
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• pp.50-55
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• 2011

The fluid power products are widely used in current industrial area such as automation of products and equipment assembly, high-tech machine tool, aircraft, train, and etc. As the development of industry is in progress, the development of the fluid power products is demanding and it is required in every industrial area. This research proposed a pneumatic system to evaluate displacement accuracy of the pneumatic actuator without external load and to analyze capability of integration of the valve system. The pneumatic system consisted of a combination of pneumatic actuator, four two-port valves, two three-port valves, two pressure valve, a check valve, two proximity sensors, and a program logic controller (PLC). The position controller is based on the PLC connected with the proximity sensors. The maximum air pressure applied for tests was $49.05N/cm^2$ and the displacement accuracy of a stroke was measured using a dial gauge. The supply- and discharge-side of air pressure and the length of the stroke of the pneumatic cylinder were varied The test of the position control of the pneumatic cylinder was carried out 50 times at each supply- and discharge-side air pressure of 24.53/34.34, 29.43/39.24, 34.34/44.15, and $39.24/49.05N/cm^2$ and replicated three times. The accuracy of the displacement of the pneumatic cylinder stroke increased as the supply- and discharge-side of air pressure increased with the stroke length of 133mm. Also the displacement accuracy increased as the stroke length increased with the fixed supply- and discharge-side of air pressure of the pneumatic cylinder as 34.34 and $44.15N/cm^2$, respectively. The most accurate displacement of the pneumatic cylinder was obtained at the supplyand discharge-side of air pressure of 39.24 and $49.05N/cm^2$, respectively, and strokes of 170 and 190mm.

• Korean Journal of Microbiology
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• v.34 no.4
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• pp.236-242
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• 1998

While bacteriophage P2-P4 system is very useful experimental tool for the study of viral capsid assembly, there is no useful plasmid vector for the DNA manipulation in bacteriophage P2-P4 system. In this study, a new vector plasmid, P4 ash8 (sid71) kmr, was constructed by swapping the non-essential region of P4 DNA for kanamycin resistance(kmr) gene cassette of plasmid pUC4-K. P4 ash8 sid71 was starting material for the construction, since it tends to be maintained as a plasmid in the absence of the helper phage. The total size of this chimera was designed to be packaged into P4 or P2 size heads with induction by P2 infection. The conversion of plasmid P4 ash8 (sid71) kmr to bacteriophage was proved by burst size determination experiment and CsCl buoyant equilibrium density gradient experiment. Integrase destructed P4 derivative, P4 ash8 sid71 kmr intS, was able to be constructed easily by in vitro DNA manipulation of P4 ash8 sid71 kmr. The plasmid stability experiment with P4 ash8 sid71 kmr if/tS showed that the integrase of P4 affects the stable maintenance of plasmid P4 state.

• Gut and Liver
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• v.12 no.6
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• pp.722-727
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• 2018

Background/Aims: Although endoscopic bilateral stent-instent placement is challenging, many recent studies have reported promising outcomes regarding technical success and endoscopic re-intervention. This study aimed to evaluate the technical accessibility of stent-in-stent placement using large cell-type stents in patients with inoperable malignant hilar biliary obstruction. Methods: Forty-three patients with inoperable malignant hilar biliary obstruction from four academic centers were prospectively enrolled from March 2013 to June 2015. Results: Bilateral stent-in-stent placement using two large cell-type stents was successfully performed in 88.4% of the patients (38/43). In four of the five cases with technical failure, the delivery sheath of the second stent became caught in the hook-cross-type vertex of the large cell of the first stent, and subsequent attempts to pass a guidewire and stent assembly through the mesh failed. Functional success was achieved in all cases of technical success. Stent occlusion occurred in 63.2% of the patients (24/38), with a median patient survival of 300 days. The median stent patency was 198 days. The stent patency rate was 82.9%, 63.1%, and 32.1% at 3, 6, and 12 months postoperatively, respectively. Endoscopic re-intervention was performed in 14 patients, whereas 10 underwent percutaneous drainage. Conclusions: Large cell-type stents for endoscopic bilateral stent-in-stent placement had acceptable functional success and stent patency when technically successful. However, the technical difficulty associated with the entanglement of the second stent delivery sheath in the hook-cross-type vertex of the first stent may preclude large cell-type stents from being considered as a dedicated standard tool for stent-in-stent placement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.171-179
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• 2021

This study was a meta-analysis of previous studies that subjected stroke patients to the whole-body vibration exercise, in an attempt to evaluate the effectiveness of such exercise in improving their balance and walking ability. The electronic databases used for literature search were the National Assembly Library, Korean Educational Academic Information (RISS), Korean Academic Information (KISS), and Nuri Media (DBPIA). We also investigated a prior study of the whole-body vibration exercise applied to stroke patients from January 2010 to August 2020. In assessing the quality of the study, the RCT (randomized controls trials) study used the risk of bias 2 (RoB2) tool developed by the Cochrane group. Meta-analysis was performed using R software for statistical computing version 4.0.3. The results of the study confirmed that the overall effect size was 0.40, and the whole-body vibration exercise used had a moderate effect on the balance and gait of stroke patients, the effect size of balance was 0.44, and the effect size of gait was 0.36, showing a positive effect. These results indicated that the whole-body vibration exercise is an effective intervention for stroke patients, and further research is needed.

• Journal of Software Assessment and Valuation
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• v.17 no.2
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• pp.109-116
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• 2021

Traditionally, the engineering field has been dominated by face-to-face education focused on experimental practice, but demand for online learning has soared due to the rapid development of IT technology and Internet communication networks and recent changes in the social environment such as COVID-19. In order for efficient online education to be conducted in the engineering field, where the proportion of experimental practice is relatively high compared to other fields, virtual laboratory practice content that can replace actual experimental practice is very necessary. In this study, we developed a line tracer model and a virtual experimental software to simulate it for efficient online learning of microprocessor applications that are essential not only in the electric and electronic field but also in the overall engineering field where IT convergence takes place. In the developed line tracer model, the user can set various hardware parameter values in the desired form and write the software in assembly language or C language to test the operation on the computer. The developed line tracer virtual experimental software has been used in actual classes to verify its operation, and is expected to be an efficient virtual experimental practice tool in online non-face-to-face classes.

• Journal of Preventive Medicine and Public Health
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• v.32 no.3
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• pp.361-373
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• 1999

Objectives: Receive Operating Characteristic(ROC) curve with the area under the ROC curve(AUC) is one of the most popular indicator to evaluate the criterion validity of the measurement tool. This study was conducted to develop a standardized questionnaire to discriminate workers at high-risk of work-related musculoskeletal disorders using ROC analysis. Methods: The diagnostic results determined by rehabilitation medicine specialists in 370 persons(89 shipyard CAD workers, 113 telephone directory assistant operators, 79 women with occupation, and 89 housewives) were compared with participant's own replies to 'the questionnair on the worker's subjective physical symptoms'(Kwon, 1996). The AUC's from four models with different methods in item selection and weighting were compared with each other. These 4 models were applied to 225 persons, working in an assembly line of motor vehicle, for the purpose of AUC reliability test. Results: In a weighted model with 11 items, the AUC was 0.8155 in the primary study population, and 0.8026 in the secondary study population(p=0.3780). It was superior in the aspects of discriminability, reliability and convenience. A new questionnaire of musculoskeletal disorder could be constructed by this model. Conclusion: A more valid questionnaire with a small number of items and the quantitative weight scores useful for the relative comparisons are the main results of this study. While the absolute reference value applicable to the wide range of populations was not estimated, the basic intent of this study, developing a surveillance fool through quantitative validation of the measures, would serve for the systematic disease prevention activities.

• Journal of KIISE:Computing Practices and Letters
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• v.9 no.4
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• pp.393-409
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• 2003

In this paper, we present a multi-task debugging environment for Qplus-T embedded-system such as internet information appliances. We will propose the structure and functions of a remote multi-task debugging environment supporting environment effective ross-development. And, we are going enhance the communication architecture between the host and target system to provide more efficient cross-development environment. The remote development toolset called Q+Esto consists to several independent support tools: an interactive shell, a remote debugger, a resource monitor, a target manager and a debug agent. Excepting a debug agent, all these support tools reside on the host systems. Using the remote multi-task debugger on the host, the developer can spawn and debug tasks on the target run-time system. It can also be attached to already-running tasks spawned from the application or from interactive shell. Application code can be viewed as C/C++ source, or as assembly-level code. It incorporates a variety of display windows for source, registers, local/global variables, stack frame, memory, event traces and so on. The target manager implements common functions that are shared by Q+Esto tools, e.g., the host-target communication, object file loading, and management of target-resident host tool´s memory pool and target system´s symbol-table, and so on. These functions are called OPEn C APIs and they greatly improve the extensibility of the Q+Esto Toolset. The Q+Esto target manager is responsible for communicating between host and target system. Also, there exist a counterpart on the target system communicating with the host target manager, which is called debug agent. Debug agent is a daemon task on real-time operating systems in the target system. It gets debugging requests from the host tools including debugger via target manager, interprets the requests, executes them and sends the results to the host.

• Journal of the Korean Society for Library and Information Science
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• v.12
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• pp.39-86
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• 1985

The main purpose of the present study is to survey the major iudexing bulletins of national nature in Korea, to define such problem areas as lacunae, duplicates and limitation in coverage in the indexing services currently available in Korea, and to make some suggestions for action for improving the existing indexing services in the light of general principles and the tradition and constraints unique to Korea. The major findings and conclusions reached at this study are summarised as follows: (A) A new indexing bulletin of general nature covering the entire field needs to be created in each of the following fields without an established indexing service available for the outcome of research and development activities in Korea. (1) Philosophy (2) Religion (3) Pure sciences (4) Art (5) Language (6) Literature (7) History (B) A new specialised indexing bulletin needs to be created in each of the following fields where indexing services are heavily utilised but no, or only partial, indexing service is available. (1) Social sciences (a) Statistics (b) Sociology (c) Folklore (d) Military science (2) Pure sciences (a) Mathematics (b) Physics (c) Chemistry (d) Astronomy (e) Geology (f) Mineralogy (g) Life sciences (h) Botany (i) Zoology (3) Applied sciences (a) Medicine (b) Agriculture (c) Civil engineering (d) Architectural engineering (e) Mechanical engineering (f) Electrical engineering (g) Chemical engineering (h) Domestic science (C) Publication of the indexing bulletins suggested in A and B above may be ideally carried on by a qualified and dependable learned society established in the respective fields and designated by the Minister of Education, and should be financially supported from the public fund under the provisions of Art. 27 of the Scientific Research Promotion Act of 1979. (D) The coverage and contents of the four indexing bulletins in the field of banking and financing published by the Library of the Bank of Korea are similar and considerably duplicated. It is, therefore, suggested that the four indexing bulletins are combined in one to form a more comprehensive and efficient bibliographical tool in the field and it is further developed into a general guide to the literature produced in the entire field of economics in Korea by gradually expanding its subject coverage. (E) For the similar reasons stated in D, the Index to the Articles on North Korea and the Catalogue of Theses on North Korea, both publisheds by the Ministry of Unification Library, are suggested to make into one. The Index to the Articles of the Selected North Korean Journals and the Index to the Articles of the North Korean Journals in Microfilm Housed in the Ministry of Unification Library, both published by the same Library, are also suggested to be combined in one. (F) The contents of the Catalogue of the Reports Submitted by Government Officials Who Have Travelled Abroad, published by the National Archives are included in the Index to the Information Materials Related to Government Administration, published by the National Archives. The publication of the former is hardly justified. (G) The contents of the Index to Legal Literature published by the Seoul National University Libraries and those of the Law Section of the Index to Scholastic Works published by the National Central Library are nearly identical. One of the two indexes should cease to be published. (H) Though five indexes are being published in the field of political science and four in the field of public administration, their subject coverage is limited. Naturally, these indexes are little usable to many other researchers in the two fields. A comprehensive index covering all the specialised areas in each field needs to be developed on one or all the existing indexes. (I) It is suggested that the Catalogue of the Scholastic Works on Curricula published by the National Central Library expands its subject coverage to become a more usable and effective index to all the researchers in the field of education. (J) The bimonthly Index to Periodical Articles and the specialised index by subject series published by the National Assembly Library, and the Index to Scholastic Works published by the National Central Library are expected to increase their coverage and frequency of publication to be used more effectively and more efficiently by all users in all fields till the indexing bulletins suggested in this study will fully be available in Korea.

• Bulletin of the Society of Naval Architects of Korea
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• v.27 no.3
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• pp.131-136
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• 1990

여러해 전부터 선박의 생산실적이나 생산성 관련 자료를 기록하고 보완하는 작업을 꾸준히 개선토록 노력해온 결과중 중요한 것 하나는, 선박의 여러 가지 설계 검토과정에서 충분히 활용할 수 있는 함축성 있고 믿을만한 형태의 생산정보를 제공해줄 수 있게 되었다는 것이라고 말 할 수 있겠다. 이러한 자료들은 생산계획상 각 단계(stage)에서의 작업량, 예상재료비와 인건비의 산출등이 포함될 수 있으며, 선박이나 해상구조물의 전반적인 설계방법론(design methodology)을 개선코자 한다면 ''생산지향적 설계(Design for Production)''의 근간이 되는 선박건조전략(build strategy), 구매정책(purchasing policy)과 생산기술(production technology)에 대한 폭넓은 지식이 한데 어우러져야 한다. 최근에는 CIMS의 일부분에서 보는 바와 같은 경영관리, 설계 및 생산지원 시스템의 도입으로 이와 같은 설계 프로세스의 추진을 가능케하고 있다. 이와 병행하여 설계를 지원하기 위한 전산기술, 특히 대화형 화상처리기술(interactive graphics)의 발달은 설계자가 선박의 형상이나 구조 배치를 여러 가지로 변화시켜 가면서 눈으로 즉시 확인할 수 있도록 설계자의 능력을 배가시키는데 크게 기여하고 있다. 여러 가지의 설계안(alternative design arrangement)을 신속히 만들어내고 이를 즉시 검토 평가할 수 있는 능력을 초기설계 단계에서 가질 수 있다면 이는 분명히 큰 장점일 것이며, 더구나 설계초기 단계에 생산관련인자를 설계에서 고려할 수 있다면 이는 더욱 두드러진 발전일 것이다. 생산공법과 관련생산 비용을 정확히 반영한 각 가지의 설계안을 짧은 시간내에 검토하고 생산소요 비용을 산출하여 비교함으로써, 수주계약단계에서 실제적인 생산공법과 신뢰성있는 생산실적자료를 기준으로 하여 총 건조비(total production cost)를 최소로 하는 최적의 설계를 선택할 수 있도록 해 줄 것이다. 이제 이와 같은 새로운 설계도구(design tool)를 제공해 주므로써 초기설계에 각종 생산관련 정보나 지식 및 실적자료가 반영가능토록 발전되었다. 본 논문은 영국의 뉴카슬대학교(Univ. of Newcastle upon Type)에서 위에 언급한 특징들을 반영하여 새로운 선박구조 설계 방법을 개발한 연구결과를 보여주고 있다. 본 선계연구는 5단계로 구분되는데; (1) 컴퓨터 그라픽스를 이용하고 생산정보 데이타베이스와 연결시켜 구조형상(geometry)을 정의하고 구조부재 칫수(scantling) 계산/결정 (2) 블럭 분할(block division) 및 강재 배치(panel arrangement)의 확정을 위해 생산기술 및 건조방식에 대한 정보 제공 (3) 상기 (1) 및 (2)를 활용하여 아래 각 생산 단계에서의 생산작업 분석(work content assessment) a) 생산 준비 단계(Preparation) b) 가공 조립 단계(Fabrication/Assembly) c) 탑재 단계(Erection) (4) 각각의 설계(안)에 대하여 재료비(material cost), 인건비(labour cost) 및 오버헤드 비용(overhead cost)을 산출키 위한 조선소의 생산시설 및 각종 품셈 정보 (5) 총 건조 비용(total production cost)을 산출하여 각각의 설계안을 비교 검토. 본 설계 방식을 산적화물선(Bulk Carrier) 설계에 적용하여 구조배치(structural geometry), 표준화의 정도(levels of standardisation), 구조생산공법(structural topology) 등의 변화에 따른 설계 결과의 민감도를 분석(sensitivity studies)하였다. 전산장비는 설계자의 대화형 접근을 용이하도록 하기 위해 VAX의 화상 처리장치를 이용하여 각 설계안에 대한 구조형상과 작업분석, 건조비 현황 등을 제시할 수 있도록 하였다. 결론적으로 본 연구는 설계초기 단계에서 상세한 건조비 모델(detailed production cost model)을 대화형 화상 처리방법에 접합시켜 이를 이용하여 여러가지 설계안의 도출과 비교검토를 신속히 처리할 수 있도록 함은 물론, 각종 생산 실적정보를 초기설계에 반영하는 최초의 시도라고 믿으며, 생산지향적(Design for Production) 최적설계분야의 발전에 많은 도움이 되기를 기대해 마지 않는다. 참고로 본 시스템의 설계 적용결과를 부록에 요약 소개하며, 상세한 내용은 참고문헌 [4] 또는 [7]을 참조 요망한다.

• The Korean Journal of Archival Studies
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• no.23
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• pp.141-178
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• 2010

The Administration of Labor was responsible for the technical and practical functions like policy-making of labor matters and implementing the relevant laws. However, there has been a few record transferred to the National Archives to help find out the labor policy-making process. This is one of the typical examples that shows the discontinuity and unbalance, and disorderly filing of the administrative records in Korea. Naturally it is almost impossible to retrieve the appropriate content through the records file-name. Users should be at the trouble to compare the record items and their content one by one. For the re-organization of the Administration of Labor' records, this research suggests the four-level analysis of functions of the Administration. The Administration of Labor' survived records could be linked to each level function. And the publication of the 'Records Abstract Catalog' providing users with more information about the records would pave the way for easier access to the records. In addition, it also suggests the logical re-filing of the survived records of which we cannot find the order or sequence. This re-organization of the survived records would help to establish the acquisition and appraisal policy of the labor records as well as the new way of description and finding tool hereafter. Drawing up labor history map is a starting point for the acquisition strategy of the labor records, which could allow users to gain systematic access on the survived records. Of course, extensive investigation and research on the survived records is a prerequisite for the map. It would be required to research on the survived records of the other government agencies, including economic-social area ministries and investigation agencies and the National Assembly as well. It is also needed to arrange and typify the significant incidents and activities on thematic and periodic frames in the labor history. If possible to understand or connect the survived records and these accomplishments comprehensively, it would be of great help for the acquisition of the labor records and the related oral records projects.