• Title/Summary/Keyword: complicated system

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Dispute of Part-Whole Representation in Conceptual Modeling (부분-전체 관계에 관한 개념적 모델링의 논의에 관하여)

  • Kim, Taekyung;Park, Jinsoo;Rho, Sangkyu
    • Journal of Intelligence and Information Systems
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    • v.18 no.4
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    • pp.97-116
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    • 2012
  • Conceptual modeling is an important step for successful system development. It helps system designers and business practitioners share the same view on domain knowledge. If the work is successful, a result of conceptual modeling can be beneficial in increasing productivity and reducing failures. However, the value of conceptual modeling is unlikely to be evaluated uniformly because we are lack of agreement on how to elicit concepts and how to represent those with conceptual modeling constructs. Especially, designing relationships between components, also known as part-whole relationships, have been regarded as complicated work. The recent study, "Representing Part-Whole Relations in Conceptual Modeling : An Empirical Evaluation" (Shanks et al., 2008), published in MIS Quarterly, can be regarded as one of positive efforts. Not only the study is one of few attempts of trying to clarify how to select modeling alternatives in part-whole design, but also it shows results based on an empirical experiment. Shanks et al. argue that there are two modeling alternatives to represent part-whole relationships : an implicit representation and an explicit one. By conducting an experiment, they insist that the explicit representation increases the value of a conceptual model. Moreover, Shanks et al. justify their findings by citing the BWW ontology. Recently, the study from Shanks et al. faces criticism. Allen and March (2012) argue that Shanks et al.'s experiment is lack of validity and reliability since the experimental setting suffers from error-prone and self-defensive design. They point out that the experiment is intentionally fabricated to support the idea, as such that using concrete UML concepts results in positive results in understanding models. Additionally, Allen and March add that the experiment failed to consider boundary conditions; thus reducing credibility. Shanks and Weber (2012) contradict flatly the argument suggested by Allen and March (2012). To defend, they posit the BWW ontology is righteously applied in supporting the research. Moreover, the experiment, they insist, can be fairly acceptable. Therefore, Shanks and Weber argue that Allen and March distort the true value of Shanks et al. by pointing out minor limitations. In this study, we try to investigate the dispute around Shanks et al. in order to answer to the following question : "What is the proper value of the study conducted by Shanks et al.?" More profoundly, we question whether or not using the BWW ontology can be the only viable option of exploring better conceptual modeling methods and procedures. To understand key issues around the dispute, first we reviewed previous studies relating to the BWW ontology. We critically reviewed both of Shanks and Weber and Allen and March. With those findings, we further discuss theories on part-whole (or part-of) relationships that are rarely treated in the dispute. As a result, we found three additional evidences that are not sufficiently covered by the dispute. The main focus of the dispute is on the errors of experimental methods: Shanks et al. did not use Bunge's Ontology properly; the refutation of a paradigm shift is lack of concrete, logical rationale; the conceptualization on part-whole relations should be reformed. Conclusively, Allen and March indicate properly issues that weaken the value of Shanks et al. In general, their criticism is reasonable; however, they do not provide sufficient answers how to anchor future studies on part-whole relationships. We argue that the use of the BWW ontology should be rigorously evaluated by its original philosophical rationales surrounding part-whole existence. Moreover, conceptual modeling on the part-whole phenomena should be investigated with more plentiful lens of alternative theories. The criticism on Shanks et al. should not be regarded as a contradiction on evaluating modeling methods of alternative part-whole representations. To the contrary, it should be viewed as a call for research on usable and useful approaches to increase value of conceptual modeling.

A Dynamic Management Method for FOAF Using RSS and OLAP cube (RSS와 OLAP 큐브를 이용한 FOAF의 동적 관리 기법)

  • Sohn, Jong-Soo;Chung, In-Jeong
    • Journal of Intelligence and Information Systems
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    • v.17 no.2
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    • pp.39-60
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    • 2011
  • Since the introduction of web 2.0 technology, social network service has been recognized as the foundation of an important future information technology. The advent of web 2.0 has led to the change of content creators. In the existing web, content creators are service providers, whereas they have changed into service users in the recent web. Users share experiences with other users improving contents quality, thereby it has increased the importance of social network. As a result, diverse forms of social network service have been emerged from relations and experiences of users. Social network is a network to construct and express social relations among people who share interests and activities. Today's social network service has not merely confined itself to showing user interactions, but it has also developed into a level in which content generation and evaluation are interacting with each other. As the volume of contents generated from social network service and the number of connections between users have drastically increased, the social network extraction method becomes more complicated. Consequently the following problems for the social network extraction arise. First problem lies in insufficiency of representational power of object in the social network. Second problem is incapability of expressional power in the diverse connections among users. Third problem is the difficulty of creating dynamic change in the social network due to change in user interests. And lastly, lack of method capable of integrating and processing data efficiently in the heterogeneous distributed computing environment. The first and last problems can be solved by using FOAF, a tool for describing ontology-based user profiles for construction of social network. However, solving second and third problems require a novel technology to reflect dynamic change of user interests and relations. In this paper, we propose a novel method to overcome the above problems of existing social network extraction method by applying FOAF (a tool for describing user profiles) and RSS (a literary web work publishing mechanism) to OLAP system in order to dynamically innovate and manage FOAF. We employed data interoperability which is an important characteristic of FOAF in this paper. Next we used RSS to reflect such changes as time flow and user interests. RSS, a tool for literary web work, provides standard vocabulary for distribution at web sites and contents in the form of RDF/XML. In this paper, we collect personal information and relations of users by utilizing FOAF. We also collect user contents by utilizing RSS. Finally, collected data is inserted into the database by star schema. The system we proposed in this paper generates OLAP cube using data in the database. 'Dynamic FOAF Management Algorithm' processes generated OLAP cube. Dynamic FOAF Management Algorithm consists of two functions: one is find_id_interest() and the other is find_relation (). Find_id_interest() is used to extract user interests during the input period, and find-relation() extracts users matching user interests. Finally, the proposed system reconstructs FOAF by reflecting extracted relationships and interests of users. For the justification of the suggested idea, we showed the implemented result together with its analysis. We used C# language and MS-SQL database, and input FOAF and RSS as data collected from livejournal.com. The implemented result shows that foaf : interest of users has reached an average of 19 percent increase for four weeks. In proportion to the increased foaf : interest change, the number of foaf : knows of users has grown an average of 9 percent for four weeks. As we use FOAF and RSS as basic data which have a wide support in web 2.0 and social network service, we have a definite advantage in utilizing user data distributed in the diverse web sites and services regardless of language and types of computer. By using suggested method in this paper, we can provide better services coping with the rapid change of user interests with the automatic application of FOAF.

Calculation of Water Level Variations and Extreme Waves in Busan Harbor due to Storm Surges (고조로 인한 부산항 해수면 변화 및 극한파랑의 산정)

  • Whang Ho-Dong;Lee Joong-Woo;Kwon So-Hyun;Yang Sang-Yong;Gum Dong-Ho
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2004.11a
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    • pp.227-234
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    • 2004
  • Recently huge typhoons had attacked to the coastal waters in Korea and caused disastrous casualties in those area. There are some discussions on correction to the design parameters for the coastal structures. Wave transformation computations with the extreme waves are of value in planning and constructing engineering works, especially in coastal regions. Prediction of typhoon surge elevations is based primarily on the use of a numerical model in this study, since it is difficult to study these events in real time or with use of physical models. Wave prediction with a two dimensional numerical model for a site with complicated coastal lines and structures at the period of typhoon 'Maemi' is discussed. In order to input parameters for the extreme wave conditions, we analyzed the observed and predicted typhoon data. Finally we applied the model discussed above to the storm surge and extreme wave problem at Busan Harbor, the southeast coast of Korea. Effects of water level variation and transformation of the extreme waves in relation with the flooding in coastal waters interested are analyzed. We then mack an attempt to presen a basic hazard map for the corresponding site.

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Features and Cost Reduction Effect of High Pressure LNG Pipeline Network (고압 LNG 배관망의 특성 및 비용절감 효과)

  • Kim, Ho-Yeon;Hong, Young-Soo;Noh, Joo-Young;Eom, Yun-Seong;Kim, Cheol-Man
    • Journal of Energy Engineering
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    • v.17 no.3
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    • pp.139-144
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    • 2008
  • Recently due to march as the high oil price, It is necessary for Korea to grope a plan, which is to increase the energy efficiency of existing facilities as well as to develop overseas gas and oil resources. With this point, this work carried out to approach the high pressure LNG pipeline network of Inchon receiving terminal with Newton method as corrective flowrate. We found that the high pressure network mainly depends on FCVs(Flow Control Valves). The high pressure pump showed the maximum efficiency at the FCVs of 50% opening and could discharge LNG only above the LNG head of 1,500m from a system curve obtained. The operating cost of pumps was estimated from their operating points. We compared the operating cost under normal operation with the operating cost under maximum efficiency. Especially, we obtained the day savings of a year as wells as the hour savings of a day. From the results, the high pressure network win be able to reduce the operating cost of 138 million wons in a year. This means that a pump can reduce the operating cost of 9,823 thousands won. Consequently, this work could find the operating features of the pumps under the complicated high pressure LNG network and the savings effect of the pump operating cost. Also, the results will be able to macroscopically contribute the heightening of national energy competitiveness as well as to microscopically contribute the future effective operation of LNG receiving terminal.

Structure Determination of Nano-crystalline, $BaTiO_3$, using Precession Electron Diffraction (세차전자회절을 이용한 $BaTiO_3$ 나노 결정의 구조분석)

  • Song, Kyung;Kim, Youn-Joong;Kwon, Ki-Hyun;Kim, Jin-Gyu;Moon, Sun-Min;Cho, Nam-Hee
    • Applied Microscopy
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    • v.39 no.4
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    • pp.341-348
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    • 2009
  • The crystal structure of nano-crystalline, $BaTiO_3$, with the average particle size of 100 nm was investigated using electron diffraction techniques. We characterized the precession electron diffraction system and then carried out the structure determination using precession electron diffraction and conventional selected area electron diffraction. As a result, it was revealed that $BaTiO_3$ nano-crystalline exist as a mixture of tetragonal structure and cubic structure by precession electron diffraction technique. In addition, it could be turned out that $BaTiO_3$ nano-crystalline is a core-shell structure consisted of a tetragonal phased core and a cubic phased surface layer by theoretical calculation. The thickness of the cubic surface layer was approximately 8.5 nm and the lattice parameters of cubic and tetragonal phases were a=3.999${\AA}$ and a=3.999${\AA}$, c=4.022${\AA}$, respectively. Finally, it is expected that precession electron diffraction is more useful technique for structure determination of complicated nano-crystalline materials because of its higher spatial resolution and minimization of dynamical scattering effect.

Developing Evaluation Criteria for Enterprise UX (엔터프라이즈 UX를 위한 평가 기준 개발)

  • Jung, Tae-Won;Yoon, So-Yeon;Nam, You-Seon;Seong, Da-In;Yoon, Yea-Jin;Lee, Min-Ho;Song, Sa-Kwang;Ha, Kwang-Soo
    • The Journal of the Korea Contents Association
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    • v.20 no.4
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    • pp.99-110
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    • 2020
  • Recently, as User Experience (UX) is considered as an important concept in the service design process of various fields, securing usability of Enterprise UX, UX developed for professional users, is acknowledged as an essential factor to increase work efficiency. The interface of Enterprise UX is complex and technically difficult for it is targeted for professional users. Thus, creating problems with complicated planning and relatively insufficient concerns regarding usability due to emphasis on development efficiency. It is necessary to consider various methods of usability, regarding further improvement is arduous in aspects of development and the cost. Therefore, this study aims to define the concept and specificity of Enterprise UX to improve usability and system effectively, and verify the main factors that reduce the usability of Enterprise UX. The evaluation of the research enterprise service, RDP (Research Data Platform), was conducted to establish and verify hypothesis. Furthermore, an independent evaluation standard for Enterprise UX is proposed after testing speculating factors that lower the usability of Enterprise UX. It is expected to utilize the Enterprise UX usability criteria defined through this study as a base data in enhancing usability and in designing Enterprise S/W.

Development of a Simulator for Optimizing Semiconductor Manufacturing Incorporating Internet of Things (사물인터넷을 접목한 반도체 소자 공정 최적화 시뮬레이터 개발)

  • Dang, Hyun Shik;Jo, Dong Hee;Kim, Jong Seo;Jung, Taeho
    • Journal of the Korea Society for Simulation
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    • v.26 no.4
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    • pp.35-41
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    • 2017
  • With the advances in Internet over Things, the demand in diverse electronic devices such as mobile phones and sensors has been rapidly increasing and boosting up the researches on those products. Semiconductor materials, devices, and fabrication processes are becoming more diverse and complicated, which accompanies finding parameters for an optimal fabrication process. In order to find the parameters, a process simulation before fabrication or a real-time process control system during fabrication can be used, but they lack incorporating the feedback from post-fabrication data and compatibility with older equipment. In this research, we have developed an artificial intelligence based simulator, which finds parameters for an optimal process and controls process equipment. In order to apply the control concept to all the equipment in a fabrication sequence, we have developed a prototype for a manipulator which can be installed over an existing buttons and knobs in the equipment and controls the equipment communicating with the AI over the Internet. The AI is based on the deep learning to find process parameters that will produce a device having target electrical characteristics. The proposed simulator can control existing equipment via the Internet to fabricate devices with desired performance and, therefore, it will help engineers to develop new devices efficiently and effectively.

Numerical Design of Double Quantum Coherence Filter for the Detection of Myo-Inositol In vivo (인체 내 myo-Inositol 검출을 위한 수치해석적 이중양자 필터 디자인)

  • Lee, Yun-Jung;Jung, Jin-Young;Noh, Hyung-Joon;Yu, Ung-Sik;Kim, Hyeon-Jin
    • Investigative Magnetic Resonance Imaging
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    • v.13 no.2
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    • pp.117-126
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    • 2009
  • Purpose : A numerical method of designing a multiple quantum filter (MQF) is presented for the optimum detection of myo-inositol (mI), an important brain metabolite, by using in vivo proton nuclear magnetic resonance spectroscopy ($^1$-HMRS). Materials and Methods : Starting from the characterization of the metabolite, the filter design includes the optimization of the sequence parameters such as the two echo times (TEs), the mixing time (TM), and the flip angle and offset frequency of the 3rd $90^{\circ}$ pulse which converts multiple quantum coherences (MQCs) back into single quantum coherences (SQCs). The optimized filter was then tested both in phantom and in human brains. Results : The results demonstrate that the proposed MQF can improve the signal-to-background ratio of the target metabolite by a factor of more than three by effectively suppressing the signal from the background metabolites. Conclusion : By incorporating a numerical method into the design of MQFs in $^1$-HMRS the spectral integrity of a target metabolite, in particular, with a complicated spin system can be substantially enhanced.

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A Fast Flight-path Generation Algorithm for Virtual Colonoscopy System (가상 대장 내시경 시스템을 위한 고속 경로 생성 알고리즘)

  • 강동구;이재연;나종범
    • Journal of Biomedical Engineering Research
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    • v.24 no.2
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    • pp.77-82
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    • 2003
  • Virtual colonoscopy is a non-invasive computerized procedure to detect polyps by examining the colon from a CT data set. To fly through the inside of colons. the extraction of a suitable flight-path is necessary to Provide the viewpoint and view direction of a virtual camera. However. manual path extraction by Picking Points is a very time-consuming and difficult task due 1,c, the long and complex shape of colon. Also, existing automatic methods are computationally complex. and tend to generate an improper and/or discontinuous path for complicated regions. In this paper, we propose a fast flight-path generation algorithm using the distance and order maps. The order map Provides all Possible directions of a path. The distance map assigns the Euclidean distance value from each inside voxel to the nearest background voxel. By jointly using these two maps. we can obtain a proper centerline regardless of thickness and curvature of an object. Also, we Propose a simple smoothing technique that guarantees not to collide with the surface of an object. The phantom and real colon data are used for experiments. Experimental results show that for a set of human colon data, the proposed algorithm can provide a smoothened and connected flight-path within a minute on an 800MHz PC. And it is proved that the obtained flight-Path provides successive volume-rendered images satisfactory for virtual navigation.

Stress Distribution on Construction Joint of Prestressed Concrete bridge Members with Tendon Couplers (텐던커플러를 사용한 프리스트레스트 콘크리트 교량부재의 이음부 응력분포 특성)

  • 오병환;채성태;김병석;이만섭
    • Journal of the Korea Concrete Institute
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    • v.13 no.1
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    • pp.1-8
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    • 2001
  • Recently, prestressed concrete(PSC) bridge structures with many repetitive spans have been widely constructed using the segmental construction method in many countries. In these segmentally constructed PSC bridges, there exist many construction joints which is required coupling of tendons or overlapping of tendons to introduce continuous prestress through several spans of bridges. The purpose of this paper is to investigate in detail the complicated stress distributions around the tendon coupled joints in prestressed concrete girders. To this end, a comprehensive experimental program has been set up and a series of specimens have been tested to identify the effects of tendon coupling. The present study indicates that the longitudinal and transverse stress distributions of PSC girders with tendon couplers are quite different from those of PSC girders without tendon couplers. It is seen that the longitudinal compressive stresses introduced by prestressing are greatly reduced around coupled joints according to tendon coupling ratios. The large reduction of compressive stresses around the coupled joints may cause deleterious cracking problems in PSC girder bridges due to tensile stresses arising from live loads, shrinkage and temperature effects. The analysis results by finite element method correlate very well with test results observed complex strain distributions of tendon coupled members. It is expected that the results of this paper will provide a good basis for realistic design guideline around tendon coupled joints in PSC girder bridges.