• Title/Summary/Keyword: Chain of events

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Analyze the parameter uncertainty of SURR model using Bayesian Markov Chain Monte Carlo method with informal likelihood functions

  • Duyen, Nguyen Thi;Nguyen, Duc Hai;Bae, Deg-Hyo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2021.06a
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    • pp.127-127
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    • 2021
  • In order to estimate parameter uncertainty of hydrological models, the consideration of the likelihood functions which provide reliable parameters of model is necessary. In this study, the Bayesian Markov Chain Monte Carlo (MCMC) method with informal likelihood functions is used to analyze the uncertainty of parameters of the SURR model for estimating the hourly streamflow of Gunnam station of Imjin basin, Korea. Three events were used to calibrate and one event was used to validate the posterior distributions of parameters. Moreover, the performance of four informal likelihood functions (Nash-Sutcliffe efficiency, Normalized absolute error, Index of agreement, and Chiew-McMahon efficiency) on uncertainty of parameter is assessed. The indicators used to assess the uncertainty of the streamflow simulation were P-factor (percentage of observed streamflow included in the uncertainty interval) and R-factor (the average width of the uncertainty interval). The results showed that the sensitivities of parameters strongly depend on the likelihood functions and vary for different likelihood functions. The uncertainty bounds illustrated the slight differences from various likelihood functions. This study confirms the importance of the likelihood function selection in the application of Bayesian MCMC to the uncertainty assessment of the SURR model.

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A Risk Management Framework for New Product Development: A Case Study

  • Kasemset, Chompoonoot;Wannagoat, Jaruwan;Wattanutchariya, Wassanai;Tippayawong, Korrakot Y.
    • Industrial Engineering and Management Systems
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    • v.13 no.2
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    • pp.203-209
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    • 2014
  • This research designed and implemented a supply chain risk management platform and applied it to a case study of reduced-fat Lanna pork sausage as a new product development project. The proposed framework has three stages: risk identification, risk assessment, and risk mitigation. Seventeen risk agents with 17 risk events were identified based on SWOT analysis and the Porter Five Forces concept through the process of planning, sourcing, making and delivering, partially captured from the supply chain operations reference model in the first stage. In the second stage, an house of risk (HOR) framework was applied to present the impacts of each risk agent. In the third stage, eight risk agents with high impact were selected to design 21 preventive actions. Finally, three preventive actions with the highest effectiveness to difficulty ratio scores-'sales evaluation of familiar products', 'increasing distribution channels and promotions to improve sales', and 'work flow improvement for work safety'-were then recommended for this new product development.

A Solution for Sourcing Decisions under Supply Capacity Risk (공급능력 리스크를 고려한 최적 구매계획 해법)

  • Jang, Won-Jun;Park, Yang-Byung
    • Journal of Korean Institute of Industrial Engineers
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    • v.42 no.1
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    • pp.38-49
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    • 2016
  • This paper proposes a mathematical model-based solution for sourcing decisions with an objective of minimizing the manufacturer's total cost in the two-echelon supply chain with supply capacity risk. The risk impact is represented by uniform, beta, and triangular distributions. For the mathematical model, the probability vector of normal, risk, and recovery statuses are developed by using the status transition probability matrix and the equations for estimating the supply capacity under risk and recovery statuses are derived for each of the three probability distributions. Those formulas derived are validated using the sampling method. The results of the simulation study on the test problem show that the sourcing decisions using the proposed solution reduce the total cost by 1.6~3.7%, compared with the ones without a consideration of supply capacity risk. The total cost reduction increases approximately in a linear fashion as the probability of risk occurrence or reduction rate of supply capacity due to risk events is increased.

Assessment of the ENSO Impact on Frequency and Spatial Distribution of Rainfall in South Korea (ENSO가 우리나라 강우의 확률빈도와 공간분포에 미치는 영향)

  • Kim, Soo Jun;Kim, Byung Sik;Kim, Hung Soo
    • Journal of Wetlands Research
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    • v.10 no.2
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    • pp.143-153
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    • 2008
  • The purpose of this paper is to evaluate impacts of ENSO on frequency and spatial distribution of rainfall in South Korea. In this paper, First, rainfall data in 60 climate stations were categorized into Warm(El Nino), Cold(La Nina), Normal episodes based on the Cold & Warm Episodes by Season, then 100 years of daily rainfall data were generated for each episodic events(El Nino, La Nina, Normal) using Markov Chain model. Finally, Estimating frequency based flood and comparison for each episodes were conducted. From the results, it shows that there are significant changes in the rainfall frequency and the spatial distribution of rainfall among Warm(EL Nino), Cold(La Nina) and Normal episodes.

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The Effect of Uncertain Information on Supply Chain Performance in a Beer Distribution Game-A Case of Meterological Forecast Information (불확실성 정보가 맥주배송게임 기반의 공급사슬 수행도에 미치는 영향 평가 : 기상정보 사례를 중심으로)

  • Lee, Ki-Kwang;Kim, In-Gyum;Ko, Kwang-Kun
    • Journal of Information Technology Applications and Management
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    • v.14 no.4
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    • pp.139-158
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    • 2007
  • Information sharing is key to effective supply chain management. In reality, however, it is impossible to get perfect information. Accordingly, only uncertain information can be accessed in business environment, and thus it is important to deal with the uncertainties of information in managing supply chains. This study adopts meteorological forecast as a typical uncertain information. The meteorological events may affect the demands for various weather-sensitive goods, such as beer, ices, clothes, electricity etc. In this study, a beer distribution game is modified by introducing meterological forecast information provided in a probabilistic format. The behavior patterns of the modified beer supply chains are investigated. for two conditions using the weather forecast with or without an information sharing. A value score is introduced to generalize the well-known performance measures employed in the study of supply chains, i.e.. inventory, backlog, and deviation of orders. The simulation result showed that meterological forecast information used in an information sharing environment was more effective than without information sharing, which emphasizes the synergy of uncertain information added to the information sharing environment.

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A Study on the Application of Block Chain Technology on EVMS (EVMS 업무의 블록체인 기술 적용 방안 연구)

  • Kim, Il-Han;Kwon, Sun-Dong
    • Management & Information Systems Review
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    • v.39 no.2
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    • pp.39-60
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    • 2020
  • Block chain technology is one of the core elements for realizing the 4th industrial revolution, and many efforts have been made by government and companies to provide services based on block chain technology. In this study we analyzed the benefits of block chain technology for EVMS and designed EVMS block chain platform with increased data security and work efficiency for project management data, which are important assets in monitoring progress, foreseeing future events, and managing post-completion. We did the case studies on the benefits of block chain technology and then conducted the survey study on security, reliability, and efficiency of block chain technology, targeting 18 block chain experts and project developers. And then, we interviewed EVMS system operator on the compatibility between block chain technology and EVM Systems. The result of the case studies showed that block chain technology can be applied to financial, logistic, medical, and public services to simplify the insurance claim process and to improve reliability by distributing transaction data storage and applying security·encryption features. Also, our research on the characteristics and necessity of block chain technology in EVMS revealed the improvability of security, reliability, and efficiency of management and distribution of EVMS data. Finally, we designed a network model, a block structure, and a consensus algorithm model and combined them to construct a conceptual block chain model for EVM system. This study has the following contribution. First, we reviewed that the block chain technology is suitable for application in the defense sector and proposed a conceptual model. Second, the effect that can be obtained by applying block chain technology to EVMS was derived, and the possibility of improving the existing business process was derived.

Detection of Pathogenic Viruses in the Atmosphere during Asian Dust Events in Incheon City (인천지역에서 황사 기간 동안 대기 중의 바이러스 검출에 관한 연구)

  • Park, Jeong Woong;Lim, Young Hee;Kyung, Sun Young;An, Chang Hyeok;Lee, Sang Pyo;Jeong, Seong Hwan
    • Tuberculosis and Respiratory Diseases
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    • v.59 no.3
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    • pp.279-285
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    • 2005
  • Background : Ambient particles during Asian dust events are usually less than $10{\mu}m$ in size, and known to be associated with the adverse effects on the general population. There is little evidence linking Asian dust to adverse effects on the airways. In 2002, the authors found that particulate matter during Asian dust events had an effect on the symptoms and pulmonary function of patients with bronchial asthma. An aggravating factor might be that of a viral infection, but this remains unclear. Conversely, it has been speculated that African dust may carry the virus responsible for foot and mouth disease. Asian dust events are also likely to be responsible for transporting viruses, some of which are pathogenic, and common in many environments. Therefore, in this study, air samples were screened for the presence of viruses. Methods : Air samples were collected 20 times each during Asian dust events and under non-dust conditions, for at least 6 hours per sample, using a high volume air sampler (Sibata Model HV500F), with an airflow rate of 500L/min, between April and August 2003, and between April and August 2004. The samples were then screened for the presence of targeted viruses (Influenza A, B, Hog cholera virus, and Aphthovirus) using a polymerase chain reaction method. Results : One Asian dust event occurred between April and August 2003, and 3 between April and August 2004, with a 24 hour average PM10 level of $148.0{\mu}g/m^3$. The 24 hour average PM10 level was $57{\mu}g/m^3$. There was a significant difference in the PM10 concentration between dusty and clear days. No viruses (Influenza virus, Aphthovirus, and Hog cholera virus) were identified in the air samples obtained during the dusty days. Conclusions : Although no virus was detected in this study, further studies will be needed to identify suspected viruses carried during Asian dust events, employing more appropriate virus detection conditions.

Level of Awareness of Cervical and Breast Cancer Risk Factors and Safe Practices among College Teachers of Different States in India: Do Awareness Programmes Have an Impact on Adoption of Safe Practices?

  • Shankar, Abhishek;Rath, G.K.;Roy, Shubham;Malik, Abhidha;Bhandari, Ruchir;Kishor, Kunal;Barnwal, Keshav;Upadyaya, Sneha;Srivastava, Vivek;Singh, Rajan
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.3
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    • pp.927-932
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    • 2015
  • Background: Breast and cervical cancers are the most common causes of cancer mortality among women in India, but actually they are largely preventable diseases. Although early detection is the only way to reduce morbidity and mortality, there are limited data on breast and cervical cancer knowledge, safe practices and attitudes of teachers in India. The purpose of this study is to assess the level of awareness and impact of awareness programs in adoption of safe practices in prevention and early detection. Materials and Methods: This assessment was part of a pink chain campaign on cancer awareness. During cancer awareness events in 2011 at various women colleges in different parts in India, a pre-test related to cervical cancer and breast cancer was followed by an awareness program. Post-tests using the same questionnaire were conducted at the end of the interactive session, at 6 months and 1 year. Results: A total of 156 out of 182 teachers participated in the study (overall response rate was 85.7 %). Mean age of the study population was 42.4 years (range- 28-59 yrs). There was a significant increase in level of knowledge regarding cervical and breast cancer at 6 months and this was sustained at 1 year. Adoption of breast self examination (BSE) was significantly more frequent in comparison to CBE, mammography and the Pap test. Magazines and newspapers were sources for knowledge regarding screening tests for breast cancer in more than 60% of teachers where as more than 75% were educated by doctors regarding the Pap test. Post awareness at 6 months and 1 year, there was a significant change in alcohol and smoking habits. Major reasons for not doing screening test were found to be ignorance (50%), lethargic attitude (44.8%) and lack of time (34.6%). Conclusions: Level of knowledge of breast cancer risk factors, symptoms and screening methods was high as compared to cervical cancer. There was a significant increase in level of knowledge regarding cervical and breast cancer at 6 months and this was sustained at 1 year. Adoption of BSE was significantly greater in comparison to CBE, mammography and the Pap test. To inculcate safe practices in lifestyle of people, awareness programmes such as pink chain campaign should be conducted more widely and frequently.

Relaxation Phenomena observed for Single Polymer Chains

  • Watanabe, Kenji;Ohno, Naoto;Nakajima, Ken;Nishi, Toshio
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.341-341
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    • 2006
  • Nanofishing enabled us to stretch a single polymer chain with picking it at its two modified termini using atomic force microscope (AFM). Stress-strain curves obtained to date had been the result on slow pulling events and therefore observed phenomena had been interpreted as quasi-static responses. In this study, we extended the capability of nanofishing to the phenomena far from equilibrium state by giving much faster pulling speeds. We could observe a momental increase entanglement and a successive stress relaxation.

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Design and Implementation of c-Commerce Portal of Small and Medium Enterprises for Marketing (중소기업 마케팅.유통 지원을 위한 협력상거래 포탈 설계 및 구현)

  • 안요찬;서중석
    • Journal of Information Technology Applications and Management
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    • v.11 no.1
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    • pp.175-187
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    • 2004
  • Many companies have integrated their internal processes with the aid of information technology. Now the focus is on interconnecting trading partners. Collaborative commerce (also known as c-Commerce) has a key role. It is not just about making it easier for business to communicate. It is about by breaking down barriers along the entire length of the supply chain. Some c-Commerce links are permanent, others get established when and where they are needed. c-Commerce is helping business in electronic supply chains to improve product delivery while cutting costs, to strengthen relationships and to reduce lead time. In this paper, we propose the concept of collaborative commerce, and design and implement Collaborative Commerce Portal (CCP) system of small and medium enterprise for marketing support. The technical definition of CCP is set of all technical elements can do collaborative commerce between small and medium enterprises with Internet or Internet. The target information of CCP includes usual and unusual information and all other information of companies used as process events. Through this, it enhances efficiency of business processes, core information sharing and marketing activation.

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