• Title/Summary/Keyword: Causal structure

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Management Plan of Whooper Swan(Cygnus cygnus) Habitat Using Causal Loop Analysis : Focused on Eulsukdo (인과순환구조 분석을 통한 큰고니 서식환경 유지방안 -을숙도를 중심으로-)

  • Choi, Yun Eui;You, Soojin;Kang, Sung-Ryong;Choi, Byoungkoo;Chon, Jinhyung
    • Korean Journal of Environment and Ecology
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    • v.29 no.3
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    • pp.353-367
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    • 2015
  • The goal of this study is to analyze the feedback structure of habitat changes of the Whooper Swan in Eulsukdo using system thinking to suggest a management plan for ecosystem health. Using the causal loop diagrams of population changes between Whooper Swan and other bird species in Eulsukdo, we found that the environmental changes in the roosting and foraging area affect the Whooper Swan's population. The causal loop diagrams of the Whooper Swan's roosting area indicated that the environmental changes (e.g., water level, noise, bird watching, and other experience activities) may influence their population density variation. In addition, the casual loop diagrams of the Whooper Swan's foraging area showed that the Whooper Swan's population was affected by various variables that included area factors such as surface area of freshwater, frozen water, salinity, and density of Scirpus planiculmis. Furthermore, through the integrated causal loop diagram, cumulative discharge of Nakdong estuary weir and building activities were identified as the variables that affect the population of the Whooper Swan. Thus, we selected this area as the strategic point to establish a management plan for the Whooper Swan's habitat. The results of this study will help in decision making of a long-term management plan for sustaining the environmental health of the ecosystem in Eulsukdo.

Systems Thinking for the Crisis and Improvements of Healthcare Delivery System (시스템사고로 본 의료전달체계의 위기와 개선방안)

  • Chung, Yoon;Lim, Jae Min;Lee, Kyun Jick
    • Korean System Dynamics Review
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    • v.17 no.1
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    • pp.5-24
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    • 2016
  • This study structurally analyzes major inefficiency of Korea's healthcare delivery system by utilizing the systems thinking. In particular, the phenomenon of patient's concentrated visits to large hospitals, waste of resource due to competitions between clinics and large hopitals, and the structure of oversupply were visualized using the causal loop diagram. The inefficient structure of healthcare delivery system can be understood more clearly by utilizing the major system archetypes of 'success to the successful', 'tragedy of commons', 'escalation' and 'limits to growth'. This study also finds solution from archetypal structure suggested by Wolstenholme. The inefficient status of healthcare delivery system might be explained by the 'out of control' archetype. In conclusion, the public resources such as the national health insurance need to be acknowledged as the entire achievement. All the participants should cooperate with each other in order to improve the inefficiency of the healthcare delivery system. In addition, the arrangement of incentive system for cooperation, acceleration of health information technology, and development of innovative business models make the sustainable healthcare delivery system.

Crowd Activity Recognition using Optical Flow Orientation Distribution

  • Kim, Jinpyung;Jang, Gyujin;Kim, Gyujin;Kim, Moon-Hyun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.8
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    • pp.2948-2963
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    • 2015
  • In the field of computer vision, visual surveillance systems have recently become an important research topic. Growth in this area is being driven by both the increase in the availability of inexpensive computing devices and image sensors as well as the general inefficiency of manual surveillance and monitoring. In particular, the ultimate goal for many visual surveillance systems is to provide automatic activity recognition for events at a given site. A higher level of understanding of these activities requires certain lower-level computer vision tasks to be performed. So in this paper, we propose an intelligent activity recognition model that uses a structure learning method and a classification method. The structure learning method is provided as a K2-learning algorithm that generates Bayesian networks of causal relationships between sensors for a given activity. The statistical characteristics of the sensor values and the topological characteristics of the generated graphs are learned for each activity, and then a neural network is designed to classify the current activity according to the features extracted from the multiple sensor values that have been collected. Finally, the proposed method is implemented and tested by using PETS2013 benchmark data.

Effective Leadership in Public Organizations: The Impact of Organizational Structure in Asian Countries

  • Valero, Jesus N.
    • Journal of Contemporary Eastern Asia
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    • v.14 no.2
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    • pp.69-79
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    • 2015
  • Among public organizations, does variation in organizational structure explain variation in public managers' leadership styles (e.g., transformational and transactional leadership)? The study of leadership in public organizations is increasingly an area of scholarly interest partly sparked by movements to reform public organizations, particularly in the context of emergency management. There is, for example, a need for effective leadership that can help organizations respond to disasters (Kapucu et al. 2010; Van Wart and Kapucu 2011; Stern 2013). There are numerous documented cases where the lack of leadership skills has been linked to major social and economic losses as a result of poor disaster response (e.g., Hurricane Katrina in the U.S.). Yet, leadership is a complex concept and numerous theoretical frameworks have been developed to help explain it (Van Wart 2005). Practically speaking, the existence of different theories of leadership suggests that public managers can decide to exercise various styles of leadership. The style of leadership that a public manager exhibits matters because some styles are perceived to be more effective than others (Trottier et al. 2008). While the effects of leadership have been extensively studied, antecedents or predictors of leadership style have received little scholarly attention (Wright and Pandey 2009; Nielsen and Cleal 2011). The purpose of this research note then is to explore the potential causal relationship between the structure of an organization and the ability of a public manager to exercise transformational leadership in the context of emergency management in two Asian countries: South Korea and Japan. This research note consists of three main sections. The following section explores the relationship between leadership and organizational structure. The second section examines how certain concepts of leadership and organizational structure were applied in two case studies of disaster response. The final section presents some directions for future research.

A Study on the Philosophical Analysis Model and its Methodological Application of Information Systems Research.Evaluation - A Critical Realist Approach - (정보체계 탐구.평가의 철학적 분석 모델과 그 방법론적 활용: 비판 실재론적 접근)

  • Ko, Chang-Taek
    • The Journal of Information Systems
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    • v.16 no.4
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    • pp.131-155
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    • 2007
  • The purpose of this thesis is to study on the philosophical analysis model and its methodological application of information systems research evaluation from critical realist perspective. Fist of all, I examine ontological epistemological methodological assertions of critical realism. Because the philosophy of critical realism is an opportunity for information systems study. I examine Dobson and Mutch's critical realist perspective on actors-structure model. I suggest a critical realist actors-praxis-structure model. This model provides the potential for a new approach to social investigations in its provision of an ontology for the analytical separation of structure and agency. Of most importance might be the incorporation of non-humans into the analysis of social interaction and of technology into the elaboration of structures. I also examine Tsoukas's critical realistic meta-theory of management. I suggest a critical realist IS management model. This model elucidate the nature of management and delineate the scope of applicability of various perspectives on management. The causal powers of management reside in the real domain and, taken together, their logics are contradictory, the effects of their contradictory composition are contingent upon prevailing contingencies. I analyze Carlsson's theory of design knowledge. His framework builds on that the aim of IS design science research is to develop practical knowledge for the design and realization of different classes of IS initiatives, where IS are viewed as socio-technical systems and not just IT artefacts. The framework proposes that the output of IS design science research is practical IS design knowledge in the form of field-tested and grounded technological rules. The IS design knowledge is developed through an IS design science research cycle. In conclusion, I think that IS actors-praxis-structure model, meta-theoretical IS management model, and IS design knowledge model according to critical realistic approach are very useful for IS research evaluation. Nevertheless, important problems are left not resolved.

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Strategic Implications of Dynamic Causal Structure of Hype Cycle for the Sustainable Growth of Advanced IT (Hype Cycle의 동태적 인과구조와 첨단 IT의 지속가능성장을 위한 전략적 시사점)

  • Kim, Sang-Wook
    • Journal of Korea Society of Industrial Information Systems
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    • v.16 no.5
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    • pp.185-196
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    • 2011
  • In order to draw some strategic implications for the sustainable growth of emerging technologies this paper attempts to dynamics underlying the 'hype cycle' ever occurring in course of coevolution of technology and society. Particularly, a series of basic questions in the context of sustainability are explored to answer by simulating the hype system structure: What makes hype cycle occur? how to enhance the tapering level at the final stage of coevolution? what are the key policy leverages and when is the right time for the policy intervention? This study perhaps give some insights not necessarily to the academics but also to the practitioners and policy makers.

Network Connecting Structure and Contextual Meanings of Chungbuk Innovation Projects Based on the Amalgamation of Social Network Analysis and System Dynamics Approaches (SNA와 SD 방법론을 활용한 충북 지역혁신사업의 네트워크 연결구조와 함의)

  • Lee, Mi-Ra;Hong, Seong-Ho;Park, Ju-Hye;Lee, Man-Hyung
    • Korean System Dynamics Review
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    • v.10 no.2
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    • pp.103-120
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    • 2009
  • Using various data derived from the regional innovation projects in the IT and BT-sectors within Chungbuk Province, this study tries to observe formation processes of network connecting structure and their spill-over effects. Considering the dynamic nature of key issues, it applies both social network analysis and causal loop methods. After a series of simulation exercises, we find that so-called extroverted regional innovation projects, that is, ones financially supported by the central government, reveal a higher tendency in the centrality, heavily depending on a handful of well reputed organizations. It is quite similar to the reinforcing mechanism, resulting in the rich-get-richer and the poor-get-poorer. Compared with the existing documents, nonetheless, it shows relatively weak in the mechanism strength, implying the fact that regional innovation projects have significantly contributed to ameliorating the unequal distribution of innovation organizations within Chungbuk Province. On the other hand, this study concludes that all the brokerage organizations related to the regional innovation projects have settled in Chungbuk Province. Whereas the Capital Region-based organizations present a higher tendency in the knowledge-network, it seems that the regional innovation projects have significantly contributed to upgrading direct and indirect competitiveness of the local organizations.

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Covariance Structure Analysis on the Impact of Job Stress, Psychological Factors and Sleep Quality on Fatigue Symptoms among Fire Fighters (소방공무원의 직무스트레스, 사회심리적 요인 및 수면의 질이 피로수준에 미치는 영향에 대한 공분산 구조분석)

  • Lee, Hyun-Joo
    • Journal of Digital Contents Society
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    • v.19 no.3
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    • pp.489-496
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    • 2018
  • This article is to examine the influence of occupational stress, socio-psychological factors and quality of sleep on fatigue symptoms from firefighters in fire service. The correlation coefficients were obtained by a tool of Pearson analysis, and covariance structure analysis was performed on the factors affecting the level of fatigue symptoms. This result suggests that the level of firefighters' fatigue symptoms in fire service. has a causal effect with occupational stress, socio-psychological factors and quality of sleep. Therefore, it is necessary to improve the work environment and to increase organizational support to deal with firefighters' fatigue in fire service.

The Controversy on the Conceptual Foundation of Space-Time Geometry (시공간 기하학의 개념적 기초에 대한 논쟁)

  • Yang, Kyoung-Eun
    • Journal for History of Mathematics
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    • v.22 no.3
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    • pp.273-292
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    • 2009
  • According to historical commentators such as Newton and Einstein, bodily behaviors are causally explained by the geometrical structure of space-time whose existence analogous to that of material substance. This essay challenges this conventional wisdom of interpreting space-time geometry within both Newtonian and Einsteinian physics. By tracing recent historical studies on the interpretation of space-time geometry, I defends that space-time structure is a by-product of a more fundamental fact, the laws of motion. From this perspective, I will argue that the causal properties of space-time cannot provide an adequate account of the theory-change from Newtoninan to Einsteinian physics.

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Signal transfduction pathways for infection structure formation in the rice blast fungus, Magnaporthe grisea

  • Lee, Yong-Hwan;Khang, Chang-Hyun
    • Proceedings of the Botanical Society of Korea Conference
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    • 1999.07a
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    • pp.41-44
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    • 1999
  • Magnaporthe grisea (Hebert) Barr (anamorph: Pyricularia grisea) is a typical heterothallic Ascomycete and the causal agent of rice blast, one of the most destructive diseases on rice (Oryza sativa L.) worldwide. The interactions between cells of the pathogen and those of the host involve a complex of biological influences which can lead to blast disease. The early stages of infection process in particular may be viewed as a sequence of discrete and critical events. These include conidial attachment, gemination, and the formation of an appressorium, a dome-shaped and melanized infection structure. Disruption of this process at any point will result in failure of the pathogen to colonize host tissues. This may offer a new avenue for developing innovative crop protection strategies. To recognize and capture such opportunities, understanding the very bases of the pathogenesis at the cellular and molecular level is prerequisite. Much has been learned about environmental cues and endogenous signaling systems for the early infection-related morphogenesis in M. grisea during last several years. The study of signal transduction system in phytopathogenic filamentous fungi offers distinct advantages over traditional mammalian systems. Mammalian systems often contain multiple copies of important genes active in the same tissue under the same physiological processes. Functional redundancy, alternate gene splicing, and specilized isoforms make defining the role of any single gene difficult. Fungi and animals are closely related kingdoms [3], so inferences between these organisms are often justified. For many genes, fungi frequently possess only a single copy, thus phenotype can be attributed directly to the mutation or deletion of any particular gene of interest.

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