• Journal of the Korean Institute of Intelligent Systems
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• v.5 no.3
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• pp.64-72
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• 1995

This paper proposes how to tune the gains of PI controllers in case of gain change in a process control system. Controllers of PI type have been used in industry and the gains of the controllers have been tuned by expert engineers. It, therefore, takes much time and efforts to tune the controllers. It is more difficult to find gains of multi-loop processes. The tuning method of a fuzzy tuner in this paper is developed based on the assumptions that the PI controllers are of analog type and are tuned off-line, and that the characteristic values must be supplied for the tuner. A Tuner using Fuzzy Logic(FLT1 is capable of showing presentlpast states of a process control system and finding gains of PI controllers. The verfication of the FLT is shown by various experiments.

• Journal of Internet Computing and Services
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• v.2 no.2
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• pp.71-93
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• 2001

Commonly to design a database system. a conceptual database has to be designed and then it is transformed into a logical database schema prior to building a target database system. This paper proposes a method which transforms a Temporal Entity-Relationship Model(TERM) into a Temporal Object-Oriented Model(TOOM) to build an efficient database schema. I formalize the time concept in view of object versioning and specify the constraints required during transformation procedure. The proposed transformation method contributes to getting the logical temporal data from the conceptual temporal events Without any loss of semantics, Compared to other approaches of supporting various properties, this approach is more general and efficient because it is the semantically seamless transformation method by using the orthogonality of types of objects, semantics of relationships and constraints over roles.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.1
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• pp.57-67
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• 2005

Fast scalar multiplication of points on elliptic curve is important for elliptic curve cryptography applications. In order to vary field sizes depending on security situations, the cryptography coprocessors should support variable length finite field arithmetic units. To determine the effective variable length finite field arithmetic architecture, two well-known curve scalar multiplication algorithms were implemented on FPGA. The affine coordinates algorithm must use a hardware division unit, but the projective coordinates algorithm only uses a fast multiplication unit. The former algorithm needs the division hardware. The latter only requires a multiplication hardware, but it need more space to store intermediate results. To make the division unit versatile, we need to add a feedback signal line at every bit position. We proposed a method to mitigate this problem. For multiplication in projective coordinates implementation, we use a widely used digit serial multiplication hardware, which is simpler to be made versatile. We experimented with our implemented ECC coprocessors using variable length finite field arithmetic unit which has the maximum field size 256. On the clock speed 40 MHz, the scalar multiplication time is 6.0 msec for affine implementation while it is 1.15 msec for projective implementation. As a result of the study, we found that the projective coordinates algorithm which does not use the division hardware was faster than the affine coordinate algorithm. In addition, the memory implementation effectiveness relative to logic implementation will have a large influence on the implementation space requirements of the two algorithms.

• Journal of the Korean Geographical Society
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• v.40 no.4 s.109
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• pp.387-401
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• 2005

This research reviews how tourism geography studies in Anglo-American tradition have evolved since 1930s. The purposes of the research are two fold. One is to analyze the change of tourism geographies research trends in terms of research approach and major research themes. The other is to bring out the lessons from the research results for the development of Korean tourism geographies research. For these purposes, the selected papers and texts have been analyzed according to four research approaches: (1) empiricist approach, (2) positivist approach, (3) humanist approach, and (4) critical social theory approach. The major research themes are the explanation of destination through descriptive research in empiricist approach, spatial analysis and evolutionary research in positivist approach, tourist behaviour and place identity in humanist approach, and tourism and consumption in critical social theory approach. It is expected that the development of Anglo-American tourism geographies study will continue in the future because of the growth of tourism industry, the close relation of tourism and geography in nature, and the active contribution of tourism geographers.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.1
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• pp.54-59
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• 2000

This paper presents a control system that uses a fuzzy algorithm in controlling the depth of a model midwater trawl net, and experimental results carried out in the circulating water channel by using a model trawl winch system.The fuzzy controller calculates the length of the warp to be changed, based on the depth error between the desired depth and actual depth of the model trawl net and the ratio of change in the depth error. The error and the error change are calculated every sampling time. Then the control input, i.e. desirable length of the warp, is determined by inference from the linguistic control rules which an experienced captain or navigator uses in controlling the depth of the trawl winch controller and the length of the warp is changed. Two kinds of fuzzy control rules were tested, one was obtained from the actual operations used by a skilled skipper or navigator, and the other was a modified from the former by considering the hydrodynamic characteristics of the model trawl system.Two kinds of fuzzy control were tested, one was obtained fro the actual operations used by a skilled skipper or navigator, and the other was a modified from the former by considering the hydrodynamic characteristics of the model trawl system.The results of these model experiments indicate that the proposed fuzzy controllers rapidly follow the desired depth without steady-state error although the desired depth was given in one step, and show robustness properties against changes in the parameters such as the change of the towing sped. Especially, a modified rule shows smaller depth fluctuations and faster setting times than those obtained by a field oriented rule.

• Spatial Information Research
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• v.1 no.1
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• pp.17-28
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• 1993

In order to minimize vectorizing tasks, which require huge reso¬urces and time and to support the census mapping effectively, the geographic information databases structure has been studied. The steps of the new approach are as follows. : Step 1, Scanning the maps of the whole country and storing the image data in raster format. Step 2, Vectorizing the data of specific items for Census operation such as Enume¬ration District, and then linking to attribute data in the text format. Step 3, Designing the database with a Tile and Multi-layer structure to make a continuous map logically. Step 4, Implement Censlls Mapping System(CMS) for efficient mapping and retrieving. As a consequence of this study, the cost, manpower and time effectiveness was proved and it was confirmed to produce lIseful and high-qual ified maps for the Census. In the future, this system wi II be able to provide many organizations and individuals with the various data based on geographical statistical information.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.827-836
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• 2015

This study aims to research the Kisho Kurokawa's architectural concepts, that are comprised of complex theories system, for globalization of Korea. Kurokawa's architectural concepts are composed by Metabolism, Metamorphosis and Symbiosis. And intermediate zone, ambiguity, multivalence are theories that work as media in changing process levels to three main concepts and these are used as media of Metamorphosis which embody Symbiosis. Metabolism include concepts of Metamorphosis and Symbiosis. Symbiosis is comprise of concepts of Metabolism and Metamorphosis, and is a ultimate goal of these three main concepts. Metamorphosis works as a medium in changing process levels from Metabolism to Symbiosis.

• Journal of The Korean Association For Science Education
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• v.36 no.1
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• pp.29-43
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• 2016

There have been much efforts to reconstruct the science curriculum focusing on Disciplinary Core Ideas(DCI) in many countries such as America and Europe, the most practical effort has been to design a curriculum with learning progressions(LPs). LPs describe stepwise how students can systematically move toward the understanding of more sophisticated ideas or scientific activities and explain in succession the process of understanding the ideas while the students learn. In this study, a LP for ecosystems has been developed, and the developed LP is then evaluated accordingly. The Ecosystem is one of the DCI of the life science in Next Generation Science Standards(NGSS). The development process of the LP was set at step 4(Development, Assessment, Analysis, and Amendment), and developed through an iterative process of sequences. As a result of analyzing the developed LP, an assessment based on the LP provides reliable information to identifying student ability. This study proposes the development process of the LP and its methodological aspects to use Core Achievement Standards, Ordered Multiple-Choice items and the Rasch model. In addition, using the empirically proven LP suggests a way of strengthening curriculum linked to educational content, teaching methods and assessment. Utilizing the proposed development process in this study will be to present the standard into the direction of becoming part of the curriculum. Currently, the state of domestic research for the LP is still lacking. This study determined the development process of the LP and the need to conduct future research on the LPs.

• Journal of Information Management
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• v.5 no.3
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• pp.57-66
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• 1972

시스팀 설계(設計)는 지극히 복잡한 일련의 선택(選擇)으로 이루어져 있거니와, 어느 한가지 결정사항(決定事項)도 이미 내려졌거나 장차 내려질 여타의 결정(決定)들과 완전히 절연된 것은 없다. 문헌정보(文獻情報) 시스팀의 설계(設計)를 위한 시스팀 접근법(接近法)에 있어서는, 시스팀의 작업능력(作業能力), 성능(性能), 비용(費用) 및 기타 특징요인(特徵要因)을 감안하여 설계과정(設計過程)에 이루어질 제선택(諸選擇)과 이들 선택(選擇)에 내포된 세부사항(細部事項)에 대하여 세밀한 검토가 가해져야 한다. 이 보문(報文)의 저자(著者)들은 다음과 같이 6단계(段階)로 된 하나의 체계적 설계절차(設計節次)를 창도하고 있다. 1) 고정설계인자(固定設計因子)의 확인, 2) 가변설계인자(可變設計因子)의 확인, 3) 각(各) 가변설계인자(可變設計因子)에 내포된 제임의요소(諸任意要素)의 확인, 4) 제임의요소(諸任意要素) 가운데서 하나를 선택할 때 그 선택에 영향을 주는 요소(要素)의 확인, 5) 제임의요소(諸任意要素) 가운데서 하나를 선택할 때 그 선택으로 인하여 영향을 받는 요소(要素)의 확인, 및 6) 설계과정(設計過程)에서 내려야 할 제결정(諸決定)의 최적순서(最適順序) 및 결정과정(決定過程) 그 자체의 본질(本質)을 파악하기 위하여, 상술한 바 제단계(諸段階)를 통해서 밝혀진 전체 상황(狀況)에 대하여 논리적(論理的) 분석(分析)을 가(加)함.

• Korean journal of communication and information
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• v.81
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• pp.189-224
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• 2017

The case of 'Paik Jong-moon's Taped Conversation,' has presented "an important and serious challenge to the freedom of the press and democracy" in South Korea. Nevertheless, this case has not been reported by the mainstream news media. It has also been forgotten without a proper fact-finding or investigation by regulatory agencies, like The Foundation for Broadcast Culture, The Korea Communications Commission, or The National Assembly. This study aims to examine why the above has happened through in-depth interviews of reporters and TV producers, senior journalists, former and incumbent commissioners of the broadcasting regulatory agencies, and experts of the industry, as well as literature research. Here, I present three answers. First, I found two reasons the mainstream press has ignored this incident. 1) It serves for political interests instead of reporting truth. 2) Public broadcasters' watchdog role has been neutralized. Second, regulatory agencies like The Foundation for Broadcast Culture, The Korea Communications Commission and The National Assembly are ruled by political tribalism. The ruling party's members of the National Assembly and these agencies were reluctant to investigate allegations surrounding Paik Jong-moon, such as illegal dismissals, illegal intervention in programming or production, illegal recruitment and illegal business deals. That's because they considered CEO Paik an ally. Using their majority power, they have rejected the request from opposition-affiliated commissioners or from opposition lawmakers to investigate the allegations. Third, there were no alternative forces within the public broadcasters to unveil the truth. In conclusion, the legal and institutional shake-up of corporate governance is urgently needed for public broadcasters and broadcasting regulatory agencies.