• Title/Summary/Keyword: Evolution strategy

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Evaluating LIMU System Quality with Interval Evidence and Input Uncertainty

  • Xiangyi Zhou;Zhijie Zhou;Xiaoxia Han;Zhichao Ming;Yanshan Bian
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.11
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    • pp.2945-2965
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    • 2023
  • The laser inertial measurement unit is a precision device widely used in rocket navigation system and other equipment, and its quality is directly related to navigation accuracy. In the quality evaluation of laser inertial measurement unit, there is inevitably uncertainty in the index input information. First, the input numerical information is in interval form. Second, the index input grade and the quality evaluation result grade are given according to different national standards. So, it is a key step to transform the interval information input by the index into the data form consistent with the evaluation result grade. In the case of uncertain input, this paper puts forward a method based on probability distribution to solve the problem of asymmetry between the reference grade given by the index and the evaluation result grade when evaluating the quality of laser inertial measurement unit. By mapping the numerical relationship between the designated reference level and the evaluation reference level of the index information under different distributions, the index evidence symmetrical with the evaluation reference level is given. After the uncertain input information is transformed into evidence of interval degree distribution by this method, the information fusion of interval degree distribution evidence is carried out by interval evidential reasoning algorithm, and the evaluation result is obtained by projection covariance matrix adaptive evolution strategy optimization. Taking a five-meter redundant laser inertial measurement unit as an example, the applicability and effectiveness of this method are verified.

Optimization of Single-stage Mixed Refrigerant LNG Process Considering Inherent Explosion Risks (잠재적 폭발 위험성을 고려한 단단 혼합냉매 LNG 공정의 설계 변수 최적화)

  • Kim, Ik Hyun;Dan, Seungkyu;Cho, Seonghyun;Lee, Gibaek;Yoon, En Sup
    • Korean Chemical Engineering Research
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    • v.52 no.4
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    • pp.467-474
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    • 2014
  • Preliminary design in chemical process furnishes economic feasibility through calculation of both mass balance and energy balance and makes it possible to produce a desired product under the given conditions. Through this design stage, the process possesses unchangeable characteristics, since the materials, reactions, unit configuration, and operating conditions were determined. Unique characteristics could be very economic, but it also implies various potential risk factors as well. Therefore, it becomes extremely important to design process considering both economics and safety by integrating process simulation and quantitative risk analysis during preliminary design stage. The target of this study is LNG liquefaction process. By the simulation using Aspen HYSYS and quantitative risk analysis, the design variables of the process were determined in the way to minimize the inherent explosion risks and operating cost. Instead of the optimization tool of Aspen HYSYS, the optimization was performed by using stochastic optimization algorithm (Covariance Matrix Adaptation-Evolution Strategy, CMA-ES) which was implemented through automation between Aspen HYSYS and Matlab. The research obtained that the important variable to enhance inherent safety was the operation pressure of mixed refrigerant. The inherent risk was able to be reduced about 4~18% by increasing the operating cost about 0.5~10%. As the operating cost increases, the absolute value of risk was decreased as expected, but cost-effectiveness of risk reduction had decreased. Integration of process simulation and quantitative risk analysis made it possible to design inherently safe process, and it is expected to be useful in designing the less risky process since risk factors in the process can be numerically monitored during preliminary process design stage.

A Review of Service Innovation Research: A Comparison of Domestic and International Research Papers (서비스혁신 연구 동향: 국내 및 해외 주요 학술지를 중심으로)

  • Ryu, Hyun-Sun
    • Asia pacific journal of information systems
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    • v.24 no.4
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    • pp.577-610
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    • 2014
  • Although service innovation is not a new concept, innovation research in general tends to focus on technological innovation by manufacturing firms. With this view, innovation studies focus on product(e.g., goods) and process(e.g., product systems) innovation, ignoring service innovation and its inherent opportunities. Since major economy has been transformed to service economy, service innovation is considered a new effective way to sustain and gain a competitive advantage. Service innovation is no longer regarded merely as a side activity to product innovation; it has become a main research topic in its own right, accompanied by an increasing focus on services. While the number of service innovation studies has increased dramatically in the past 30 years in international research, few studies have been performed in domestic studies because domestic service innovation research began from the middle of 2000. In addition, there are no comprehensive literature reviews describing the evolution of service innovation research in both international and domestic studies because of the heterogeneities of service industry and multidiscipline characteristics of service innovation studies. To bridge this research gap, the purpose of this paper is to perform an extensive literature review and synthesis to enable a critical review of extant research on service innovation and trace its evolution, which will establish a foundation for further studies. By reviewing 169 articles (136 international papers; 33 domestic papers) published between 2000 and 2014 (in past 15 years), primarily in leading service, innovation and management information systems journals, this study analyzes the progression of service innovation research according to the four aspects such as number of studies, topics, methodologies and target industries. Overall, the view of service innovation has evolved, from a complement of traditional product innovation to a multidimensional, all-encompassing concept that entails several functions, both within and outside the firms. The results showed that domestic research still stays at the formation phase of service innovation studies although international research is in the maturity or multidimensional phase. We found increasing recent activities pertaining to service innovation, resulting from the increasing interest in services innovation across various industries and the links of new topics to the service innovation concept in both international and domestic studies. However, the main focus of service innovation research showed a different propensity between international and domestic studies: the former mainly focuses on a much more diversified pattern, emphasizing the linkages between service innovation and business strategy while the latter mainly focuses on the service innovation process(system) and service design. In addition, there are many case studies in domestic studies while many empirical studies in international studies. Domestic studies should increases the understanding of the interplay between service innovation and product innovation within manufacturing firms. Furthermore, rather than focusing on intrinsic distinctions between service innovation and product innovation, researchers should strive to develop and conceptualize service innovation in domestics studies. The present research also provides useful implications for practitioners. First, this study contributes to expand the current understanding of service innovation research by performing an extensive literature review. Second, tracing and comparing the progression and trends of service innovation research between international and domestic studies, this study showed the similarities and differences between them, which provide practical guidance on future research directions and research agenda. Third, this study performed literature review establishing the analysis system in the initial stage and using them to analyze articles, which is leading to explain the research review of service innovation more systematically and objectively. Finally, this study suggests the domestic researchers their future interests and topics of service innovation research.

An Explorative Study of R&D Priority based on Needs Attributes Model: Case of SMART TV (니즈속성의 중요성과 시급성에 의한 R&D 우선순위 결정에 관한 탐색 연구: SMART TV를 중심으로)

  • Han, Sung-Soo;Choi, Saesol
    • Journal of Korea Technology Innovation Society
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    • v.16 no.3
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    • pp.650-671
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    • 2013
  • Products elicit the consumer's purchasing behavior by satisfying their needs and are cognized as the combination of various needs attributes. Also R&D is referred as a series of technical development activities to meet the consumer's needs attributes. In particular, in the market-oriented R&D era, it could obtain the legitimacy by developing the R&D based on the needs attributes. In this study, we aimed to investigate the priority setting in R&D field, considering consumer's needs attributes. To be concrete, we tried to present the evolutional direction of desirable phased R&D according to 'the importance degree for consumers on the attributes (functions) of the certain products' and 'the urgency degree of technical quality to fulfill its needs'. To achieve this, we targeted SMART TV, the convergence product, which contains the uncertainty in terms of marketability and technological aspect, and analyzed the priority of the R&D in SMART TV field. Based on the result of the analysis, 4-steps product concept (ultra high definition TV, interactive TV, 3D/immersive TV, personalized TV) is derived by analyzing the evolutional direction of R&D in SMART TV field. This finding implies that the success possibilities of product could be enhanced during the process of the evolution of products that have multiple needs attributes, by pursuing the R&D which fulfills the needs attribute first required in the market. In addition, it provides a useful framework to design the R&D roadmap in an aspect of R&D strategy.

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The Determinants of Customer Satisfaction In Electronic Commerce. (전자상거래시 고객만족 결정요인에 관한 연구)

  • Cho, Hyun-Chul;Shim, Gyu-Yul
    • Journal of Global Scholars of Marketing Science
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    • v.7
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    • pp.261-281
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    • 2001
  • As a new environment, the Internet proposes to us the innovative change of our life. With difficulty, we can go after the Internet's potentiality and the growth speed of technology. In the new stream of innovation technology, we can probably feel the fear of tremendous changes, the reverse, also hope to get the opportunity that come out of Internet world. EC(Electronic Commerce) that out of the evolution of Internet technology gets a coporation changes to survive in 21st century. So the corporation must set the strategy to fit a Internet focused society. As one of them, a virtual store is opened on the Internet. Recently, there has been much attention to the Internet shopping mall as a new distribution channel and marketing tool. This study analyzed that the system environment, perceived product risk, easy of order, perceived security risk would have impact on the customer satisfaction in Electronic Commerce. The Purpose of this study is to develope the concept of the determinants of customer satisfaction and to test a theoretical framework that attempts to explain how the perception of satisfaction in Electronic Commerce. The proposed hypotheses were tested internet shopping mall users and the study results show all hypotheses are supported.

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A Study of Development and Implementation of Problem-based Learning Program in Communication Curriculum of Nursing Education (문제중심 학습방법을 적용한 의사소통론 교과목 개발 및 적용)

  • Hyun, Myung-Sun;Kang, In-Ae;Kong, Seong-Sook
    • The Journal of Korean Academic Society of Nursing Education
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    • v.9 no.1
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    • pp.144-154
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    • 2003
  • Recently, in the academic disciplines critical thinking has been emphasized as the new evolution in education. Problem-based learning is suggested as the evolutionary learning method in developing critical thinking. In the nursing education, PBL is offered as an appropriate teaching method to prepare nurse student for professional. PBL is a student-centered learning strategy aimed at developing critical thinking, motivating self-directed study and attaining autonomy. The purpose of this study was to develop the communication curriculum of nursing education based on PBL and implementing of it. PBL module was developed focused on five communication situations. And learning strategies to facilitate the learning process and the guided questions to stimulate student inquiry were also developed. This PBL education was conducted for six students in the master's course during the 14 weeks from March, 2000 to June, 2000. The outcomes of the PBL education were examined based on the content analysis of the students reflective journal. As a result, it was found that students experienced the effect of it focused on self-oriented, group-oriented, and practice-oriented domain. In the self-oriented domain, the findings indicate that there were 5 kinds of concepts including 'motivation for self-directed study', 'transition toward certainty in knowledge acquisition', 'attempt to apply their prior knowledge into new situation', 'enhancement of self-image in real situation', 'self-growth with self reflection'. In the group-oriented domain, there were 3 kinds of concepts including 'cognitive work in group', 'perception of co-responsibility in attaining learning objectives', 'socialization with group members'. In the practice-oriented domain, there were 3 kinds of concepts including 'linkage theoretical knowledge with real situation', 'attempt to apply in real situation', 'development problem solving skill in real situation'. In conclusion, PBL had a significant effect on self, group, and clinical domain. And assessing PBL outcomes is challenging because standardized instrument do not develop yet. So the findings of this study can suggest the basic data for examining the PBL outcome.

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Infrared Medium-Deep Survey: Overview

  • Im, Myungshin;Pak, Soojong;Park, Won-Kee;Kim, Ji Hoon;Kim, Jae-Woo;Lee, Seong-Kook J.;Karouzos, Marios;Jeon, Yiseul;Choi, Changsu;Jun, Hyunsung;Kim, Dohyeong;Hong, Jueun;Kim, Duho;Hyun, Minhee;Yoon, Yongmin;Taak, Yoon Chan;Kim, Yongjung;Baek, Giseon;Jeong, Hyeonju;Lim, Juhee;Kim, Eunbin;Choi, Nahyun;Lee, Hye-In;Bae, K.M.;Chang, Seunghyuk
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.68.1-68.1
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    • 2013
  • Infrared Medium-Deep Survey is a near-infrared imaging survey geared toward understanding the formation and the evolution of quasars and galaxies at high redshift, and studying transient and time-variable objects such as gamma-ray bursts, supernovae, and young stellar objects. The survey uses a multi-tier structure, with deep imaging survey of 100 $deg^2$ using UKIRT to the depth of 23 AB mag, and a shallower imaging of interesting sources using the CQUEAN camera on the 2.1m telescope at McDonald observatory. This talk will give an overview of the survey strategy, the instrument development, and science highlights. The science highlights will include the discovery of high redshift quasars, high redshift galaxy clusters, GRBs, and other interesting sources. At the end of the talk, we will also present the future prospects of our study.

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Decentralization from Al-Qaida central among Salafi-jihadist groups, Boko Haram and the Islamic States (살라피 지하디스트의 탈-알카에다 중심화와 보코하람, IS에 대한 분석연구)

  • Kim, Eun-Young
    • Korean Security Journal
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    • no.41
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    • pp.185-212
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    • 2014
  • This research examines the decentralization of al-Qaida and other Salafi-jihadist terrorist groups, which is a subject of intense debate in the West. Especially, this study focused on investigating the status and evolution of al Qa'ida and other two Salafi-jihadist groups, Boko Haram and the Islamic States. These terrorist groups are currently considered as the most active Salafi-jihadist terrorist groups leading today's decentralization from Al-Qaida central terrorism network. This study also aims to examine the contemporary threats posed by the two extremely violent jihadist terrorist groups and these groups's terrorist networks. In order to achieve the purpose of this study, this study conducted content analyses with a wide range of documents reporting about Salafi-jihadist terrorists groups. Also this study utilized GTD data set drwan from START centner to provide descriptive analyses regarding IS and Boko Haram's activities and threats. On the basis of analyses, this study argues that recently the threats posed by core al Qaida has been severely weakened. Further, the broader Salafi-jihadist movement has become more decentralized among four tiers: first, core al Qaida in Pakistan; second, formal al Qa'ida affiliated groups that have sworn allegiance to core al Qaida; a number of Salafi-jihadist groups that have committed to establishing an extremist Islamic emirate without sworn allegiance to al Qaida; third, individual followers and networks inspired by al Qaida and other Salafi-jihadist groups. In concusion and discussion, this study highlights the need for a long-term engagement counter terrorism strategy against Salifi-jihadist terrorists groups on behalf of the peace and security of the world society.

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A Study on the Images of the Korean Presidents in the 2000s via Stamps -Focusing on Korean President Moo-hyun Roh, Myung-bak Lee, Geun-hye Park, Jae-in Moon- (우표를 통해 본 2000년대 한국 대통령의 휴먼이미지 연구 -노무현, 이명박, 박근혜, 문재인 대통령을 중심으로-)

  • Kim, Mi-Ri;Jang, Seong-Ho
    • The Journal of the Korea Contents Association
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    • v.20 no.10
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    • pp.738-749
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    • 2020
  • The stamp commemorating the inauguration of a president is the smallest historical symbol that contains a nation's vision and wishes of the times. The stamp itself is just a collection of images but contains the meaning of the highest leader's perceived image at the time through their face and a symbol. This paper regarded presidential inauguration commemorative stamps in the context of advertisement or promotional materials to structurally analyze the images of the political leaders embedded in stamps utilizing 'semiology' theory, which is considered to be a useful method of advertisement. In accordance with social and cultural changes, the 2000s, when the changes in the presidential inauguration stamp was most distinctively noticeable, was set as the time frame. Only the presidential inauguration commemorative stamps of Moo-hyun Roh, Myung-bak Lee, Geun-hye Park, and Jae-in Moon were selected for this study. In order to interpret the image, a semiotic structure was applied to reconstruct the meaning of the image of the political leaders. Since this can lead to subjective judgment in image analysis, it attempted to find the truth through comprehensive interpretation and approach it from the social and cultural contexts, not a static approach. In this paper, the images of the Korean political leaders in the 2000s shown on stamps are no longer influenced by traditional political factors such as political parties, political ideologies, and regional origins due to the evolution of democracy. This study derives the characteristics of the images of independent and characteristic leaders centered on a person according to the situations and social phenomena of the times.

Efficacy of Antiepileptic Drug on the Benign Childhood Epilepsy with Centro-Temporal Spikes (중심-측두엽 극파를 보이는 양성 소아 간질 환자에서 항경련제 투여의 유효성)

  • Oh, Mee Hye;Kim, Soo Young;Seo, Won Hee;Pee, Dae Hun;Choi, Byung Min;Eun, Baik-Lin
    • Clinical and Experimental Pediatrics
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    • v.46 no.9
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    • pp.893-897
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    • 2003
  • Purpose : Benign childhood epilepsy with centrotemporal spikes(BECT) is characterized by an excellent prognosis. Therefore, the necessity for the use of antiepileptic drugs is controversial. The object of this study is to know about the long-term follow-up of BECT, comparing daily treatment with antiepileptic drug(AED) versus no medication. Methods : We retrospectively studied 56 cases of BECTs, examined at Pediatric Neurology Clinic, Korea University Medical Center as reference study time, August 2002. Thirty-eight patients didn't have mediation(group I), while eighteen patients received one or two AED(group II). We evaluated demographics, clinical manifestations at diagnosis, EEG findings and clinical courses in groups I & II. Results : There was no significant differences of sex, age, seizure frequency, seizure type, seizure onset time, family history and EEG findings between group I & II. The reasons to start AED were : parents' anxiety(three cases), frequent seizure(12 cases) and daytime seizure(three cases). There was no evolution of status epilepticus and no difficulty in school performance. Conclusion : AED treatment was of no advantage and long-term prognosis was good regardless of treatment strategy. So it is advisable not to choose AED as the first line of therapy, provided that the patient himself/herself or the family understands the benign nature of BECT.