• Title/Summary/Keyword: a conceptual model

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CONCEPTUAL STRUCTURAL DESIGN AND COMPARATIVE POWER SYSTEM ANALYSIS OF OZONE DYNAMICS INVESTIGATION NANO-SATELLITE (ODIN)

  • Park, Nuri;Hwang, Euidong;Kim, Yeonju;Park, Yeongju;Kang, Deokhun;Kim, Jonghoon;Hong, Ik-seon;Jo, Gyeongbok;Song, Hosub;Min, Kyoung Wook;Yi, Yu
    • Journal of The Korean Astronomical Society
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    • v.54 no.1
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    • pp.9-16
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    • 2021
  • The Ozone Dynamics Investigation Nano-Satellite (ODIN) is a CubeSat design proposed by Chungnam National University as contribution to the CubeSat Competition 2019 sponsored by the Korean Aerospace Research Institute (KARI). The main objectives of ODIN are (1) to observe the polar ozone column density (latitude range of 60° to 80° in both hemispheres) and (2) to investigate the chemical dynamics between stratospheric ozone and ozone depleting substances (ODSs) through spectroscopy of the terrestrial atmosphere. For the operation of ODIN, a highly efficient power system designed for the specific orbit is required. We present the conceptual structural design of ODIN and an analysis of power generation in a sun synchronous orbit (SSO) using two different configurations of 3U solar panels (a deployed model and a non-deployed model). The deployed solar panel model generates 189.7 W through one day which consists of 14 orbit cycles, while the non-deployed solar panel model generates 152.6 W. Both models generate enough power for ODIN and the calculation suggests that the deployed solar panel model can generate slightly more power than the non-deployed solar panel model in a single orbit cycle. We eventually selected the non-deployed solar panel model for our design because of its robustness against vibration during the launch sequence and the capability of stable power generation through a whole day cycle.

Changes in air pollutant emissions from road vehicles due to autonomous driving technology: A conceptual modeling approach

  • Hwang, Ha;Song, Chang-Keun
    • Environmental Engineering Research
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    • v.25 no.3
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    • pp.366-373
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    • 2020
  • The autonomous vehicles (AVs) could make a positive or negative impact on reducing mobile emissions. This study investigated the changes of mobile emissions that could be caused by large-scale adoption of AVs. The factors of road capacity increase and speed limit increase impacts were simulated using a conceptual modeling approach that combines a hypothetical speed-emission function and a traffic demand model using a virtual transportation network. The simulation results show that road capacity increase impact is significant in decreasing mobile emissions until the market share of AVs is less than 80%. If the road capacity increases by 100%, the mobile emissions will decrease by about 30%. On the other hand, driving speed limit increase impact is significant in increasing mobile emissions, and the environmentally desirable speed limit was found at around 95 km/h. If the speed limit increases to 140 km/h, the mobile emissions will increase by about 25%. This is because some vehicles begin to bypass the congested routes at high speeds as speed limit increases. Based on the simulation results, it is clear that the vehicle platooning technology implemented at reasonable speed limit is one of the AV technologies that are encouraging from the environmental point of view.

A Study in the Data Modeling for Archive System Applying RiC (RiC을 적용한 아카이브 시스템 데이터 모델링 연구)

  • Shin, Mira;Kim, Ikhan
    • Journal of Korean Society of Archives and Records Management
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    • v.19 no.1
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    • pp.23-67
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    • 2019
  • Records in Contexts (RiC) is an international archival description standard developed by integrating and normalizing four archival description standards of the International Council of Archives (ICA). RiC has the advantage of diversifying archival description, exposing the context of records, and ensuring data interoperability between disparate systems. In this study, RiC is set up as a key tool in the design of archive systems, and logical data modeling is performed to implement the database. Because of RiC's conceptual model, RiC-CM can be used as a data reference model, and which makes it possible to develop a data model that meets user requirements. Therefore, this study intends to implement these two data models: relational data model, which is widely used as the database on legacy systems, and graphical data model, which can flexibly extend objects around the relationship between information entities.

Constructing a Conceptual Electronic Record Management System Model Based on Eight Indonesian Education Standards to Support School Accountability

  • Nina Oktarina;Murwatiningsih;Hana Netti Purasani;Ahmad Sehabuddin;Edy Suryanto
    • Journal of Information Science Theory and Practice
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    • v.11 no.3
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    • pp.16-28
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    • 2023
  • Record management, especially in schools as an institution's information centre, needs serious attention from government agencies. Under record management policy, there needs to be practical guidance on record management specific to schools. This paper aims to construct a record management model based on the Eight Indonesian Education Standards to support school accountability in Indonesia. The urgency of this paper in filling the gap in the Electronic Record Management System (ERMS) role is primarily to support school accountability. It is important to include educational laws and regulations in Indonesia to be a foundation in archive management, including preparing the ERMS. This study aims to develop a model of record management in schools. The final stage in this research is to find the final model. The final model is a model that experts and practitioners have validated. A total of 30 records managers were selected for the interviews. Furthermore, the trial was carried out in 30 senior high schools. The research sampling consisted of representatives of archive managers at selected schools from five islands in Indonesia (Kalimantan, Java, Papua, Sumatra, and Sulawesi). Our research findings show that conceptual models meet valid criteria and significantly impact archivist performance in better schools. The practical implication is that the archival management model based on national education standards policies contributes to practical archives and records management to support school accountability.

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.

Effectuality of Cleaning Workers' Training and Cleaning Enterprises' Chemical Health Hazard Risk Profiling

  • Suleiman, Abdulqadir M.;Svendsen, Kristin V.H.
    • Safety and Health at Work
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    • v.6 no.4
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    • pp.345-352
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    • 2015
  • Background: Goal-oriented communication of risk of hazards is necessary in order to reduce risk of workers' exposure to chemicals. Adequate training of workers and enterprise priority setting are essential elements. Cleaning enterprises have many challenges and the existing paradigms influence the risk levels of these enterprises. Methods: Information on organization and enterprises' prioritization in training programs was gathered from cleaning enterprises. A measure of enterprises' conceptual level of importance of chemical health hazards and a model for working out the risk index (RI) indicating enterprises' conceptual risk level was established and used to categorize the enterprises. Results: In 72.3% of cases, training takes place concurrently with task performances and in 67.4% experienced workers conduct the trainings. There is disparity between employers' opinion on competence level of the workers and reality. Lower conceptual level of importance was observed for cleaning enterprises of different sizes compared with regional safety delegates and occupational hygienists. Risk index values show no difference in risk level between small and large enterprises. Conclusion: Training of cleaning workers lacks the prerequisite for suitability and effectiveness to counter risks of chemical health hazards. There is dereliction of duty by management in the sector resulting in a lack of competence among the cleaning workers. Instituting acceptable easily attainable safety competence level for cleaners will conduce to risk reduction, and enforcement of attainment of the competence level would be a positive step.

Online-Offline 혼합학습 형태의 Blended Learning에서 지식 창출활동 촉진을 위한 협력적 지식 창출 모형 탐색 : 초.중등교육을 중심으로

  • Park, Seon-A
    • Journal of the Korea Computer Industry Society
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    • v.7 no.5
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    • pp.521-536
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    • 2006
  • The Blended Learning of K-12 education can he complimented to exceed the limits of the traditional face-to-face instructional method and can help learners have experiences with both various interactions and different learning experiences. Specifically, in K-12 education blended learning has a strength in being able to integrate on-line instruction with off-line instruction and actively help learners emerge with a breadth of knowledge gained collaboratively.<중략>For the objective of the study, that is, an investigation by a literature review process, the mode) of the process of collaboratively emerging knowledge as well as the alternative model of the concept can be applied as a developmental research method, which can improve practical procedure, process, and prescription. For overcoming the model and the real situation, this study was applied with Checkland(1999)'s soft system methodology, using$\square$the comparison of the model and real situations$\square$part and$\square$defining the alternatives$\square$of Checkland(1999)'s methods. In conclusion, analyzing the conceptual model and real situation helps in the development of a model which can minimize the discrepancy between the conceptual model and the real situation within K-12 education.

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Reconnaissance-Strike-Logistics Complex Systems for Future Warfare in the 21st Century (21세기 미래전의 정찰.타격.군수 복합체계)

  • 권태영;이재영
    • Journal of the military operations research society of Korea
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    • v.27 no.1
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    • pp.1-9
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    • 2001
  • In this paper, "a conceptual model of Reconnaissance-Strike-Logistics Complex(RSLC) in future warfare" is proposed. Basic idea of the RSLC model is to combine logistics and the pre-existing Reconnaissance-Strike Complex(RSC) through a C4 network system. That is, the RSLC model consists of reconnaissance, strike, logistics, and C4 network systems. The C4 network system creates new combat power by integrating all the other systems. The RSLC model generates three conceptual complex circles; the RSC, the SLC(Strke-Logistics Complex), and the RSLC circles. The RSC circles describes direct combat behaviors in the battlefield. On the other hand, the SLC circle indicates combat sustainment capabilities. The RSLC circle including the RSC and the SLC circles, can present a more complete combat process. There are two key advantages of the RSLC model. First of all, logistics is considered one of key combat components to form IDA(Information-Decision-Action) cycle for combat decision-making process more completely. Secondly, the capabilities of battlefield awareness which reconnaissance and war-net systems provide, can be applied not only to the strike system in the RSC circle, but also to the logistics system in the SLC circle. Thus, the RSLC model can maximize combat synergy effects by integrating the RSC and the SLC. With a similar logic, this paper develops "A Revised System of Systems with Logistics (RSSL)" which combines "A New system of Systems" and logistics. These tow models proposed here help explain several issues such as logistics environment in future warfare, MOE(Measure of Effectiveness( on logistics performance, and COA(Course of Actions) for decreasing mass and increasing velocity. In particular, velocity in logistics is emphasized.

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Derivation of a Tank Model with a Conceptual Rainfall-Infiltration Process (개념적 강우-침투 과정을 고려한 탱크 모형의 유도)

  • Park, Haen-Nim;Cho, Won-Cheol
    • Journal of Korea Water Resources Association
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    • v.39 no.1 s.162
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    • pp.47-57
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    • 2006
  • This study derives an event-based tank model with a conceptual rainfall-infiltration process, modifying conventional tank models. The model comprises two serial tanks, one parallel tank and an infiltration regulating element. The infiltration process within the element is not represented as a function of only time, but as a function of soil moisture content for three possible cases owing to the relationship between rainfall intensity and infiltration capacity. This study considers the previous soil moisture condition of a watershed by using antecedent precipitation index. Six parameters of the model are identified by using the real coded genetic algorithm. The applicability and validity of the proposed model are assessed for the observed stormwater data from the research basin of the International Hydrological Program, the Pyeongchanggang River basin, Republic of Korea. The results computed streamflows show relatively good agreement with observed ones.

Conceptual Design of Small WIG Craft (소형 위그선 개념 설계)

  • Shin, Myung-Soo;Kim, Yoon-Sik;Lee, Gyeong-Joong;Kang, Kuk-Jin;Park, Young-Ha;Lee, Young-yeon
    • Journal of the Society of Naval Architects of Korea
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    • v.43 no.1 s.145
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    • pp.134-146
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    • 2006
  • This paper presents the primary conceptual design results of twenty-passenger class Wing-In-Ground(WIG) effect craft. As a first step, top level requirements were proposed and principal dimensions were determined. Maximum speed in ground effect condition is 150 km/h with two tons payload including passengers. Total weight is estimated as 8.5 tons with 2 tons of thrust. Hull and airfoil sections were designed and self propulsion tests were performed by radio controlled model. Two planing hull forms with the transom stern were proposed and towing tests were performed. The resistance and running attitude were measured and the feasibility is checked for the prototype hull form of the twenty-passenger class WIG craft. The free running tests show the stable smooth running attitude at designed speed. Also this radio controlled model can take off around 0.15 meter wave height. It can be said that the top level requirement for the twenty passenger class WIG ship is satisfied successfully. The design optimization to increase the transport efficiency and safety will be performed in the near future.