• Title/Summary/Keyword: lessons learned

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Temporal Change in Radiological Environments on Land after the Fukushima Daiichi Nuclear Power Plant Accident

  • Saito, Kimiaki;Mikami, Satoshi;Andoh, Masaki;Matsuda, Norihiro;Kinase, Sakae;Tsuda, Shuichi;Sato, Tetsuro;Seki, Akiyuki;Sanada, Yukihisa;Wainwright-Murakami, Haruko;Yoshimura, Kazuya;Takemiya, Hiroshi;Takahashi, Junko;Kato, Hiroaki;Onda, Yuichi
    • Journal of Radiation Protection and Research
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    • v.44 no.4
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    • pp.128-148
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    • 2019
  • Massive environmental monitoring has been conducted continuously since the Fukushima Daiichi Nuclear Power accident in March of 2011 by different monitoring methods that have different features together with migration studies of radiocesium in diverse environments. These results have clarified the characteristics of radiological environments and their temporal change around the Fukushima site. At three months after the accident, multiple radionuclides including radiostrontium and plutonium were detected in many locations; and it was confirmed that radiocesium was most important from the viewpoint of long-term exposure. Radiation levels around the Fukushima site have decreased greatly over time. The decreasing trend was found to change variously according to local conditions. The air dose rates in environments related to human living have decreased faster than expected from radioactive decay by a factor of 2-3 on average; those in pure forest have decreased more closely to physical decay. The main causes of air dose rate reduction were judged to be radioactive decay, movement of radiocesium in vertical and horizontal directions, and decontamination. Land-use categories and human activities have significantly affected the reduction tendency. Difference in the air dose rate reduction trends can be explained qualitatively according to the knowledge obtained in radiocesium migration studies; whereas, the quantitative explanation for individual sites is an important future challenge. The ecological half-lives of air dose rates have been evaluated by several researchers, and a short-term half-life within 1 year was commonly observed in the studies. An empirical model for predicting air dose rate distribution was developed based on statistical analysis of an extensive car-borne survey dataset, which enabled the prediction with confidence intervals. Different types of contamination maps were integrated to better quantify the spatial data. The obtained data were used for extended studies such as for identifying the main reactor that caused the contamination of arbitrary regions and developing standard procedures for environmental measurement and sampling. Annual external exposure doses for residents who intended to return to their homes were estimated as within a few millisieverts. Different forms of environmental data and knowledge have been provided for wide spectrum of people. Diverse aspects of lessons learned from the Fukushima accident, including practical ones, must be passed on to future generations.

A Study of BIM-based Construction Management Work Process Development in Design Phase (설계단계의 BIM기반 CM 업무 프로세스 개발에 관한 연구 - 설계관리 업무를 중심으로 -)

  • Lee, Seoyun;Ham, Namhyuk;Kim, Juhyung;Kim, Jaejun
    • Korean Journal of Construction Engineering and Management
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    • v.14 no.6
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    • pp.90-101
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    • 2013
  • A typical construction project involves participation of various parties including clients, contractors, architects, and engineers for its successful completion, and yet has intrinsic differences of interests among the participants during the project execution period. A construction management (CM) services's role is then to resolve these differences of interests among the participants during the project execution, and lead the projects to its successful completion while representing the clients' demands and interests. The use of building information modeling (BIM) is increasing recently among construction projects, and those CM service companies are experiencing difficulties applying BIM. This is because the use of BIM in construction projects suggests a quite new set of operational paradigm. The purpose of this paper is then to review the recent cases of projects which used BIM; to analyze the these projects' processes; to reengineer the design phase process based on the lessons learned from recent BIM application; and to suggest a modified design phase process model that could improve the use of BIM and related coordination operations.

Growth Model for Korean CM Firms based on 2012 Statistics (CM기업의 단계별 발전 전략 모델: 2012년 실적자료 기반 분석)

  • Jung, Youngsoo;Shin, Dongwoo;Kang, Seunghee;Kim, Namjoon
    • Korean Journal of Construction Engineering and Management
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    • v.15 no.6
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    • pp.92-104
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    • 2014
  • CM services have been increasingly practiced over the two decades in the Korean construction industry, and recent efforts focus on further development in advanced CM capabilities and expansion to overseas market. However, there has been lack of holistic research to investigate current status and future direction of CM industry in Korea. In this context, the purposes of this study are 1) to analyze current status of Korean CM industry in terms of owners, market, CM firms, contracts, and work scopes, 2) to define different types of CM practices, and 3) to propose growth models for Korean CM firms based on the defined CM project types. An extensive literature review and statistical analysis of 2012 CM contracts were performed in order to analyze the CM status. Based on the analyses, ten different CM types are defined, and growth paths of CM firms are illustrated. Implications and lessons learned during the statistical analysis and workshops are briefly introduced as well.

Methodologic Lessons Learned from Multicenter, Randomized, Controlled Clinical Trial of Acupuncture for Hot Flashes in Peri- and Postmenopausal Women (갱년 및 폐경 후 여성의 안면홍조에 대한 침 치료 다기관 임상연구 : 수행보고 및 방법론적 교훈)

  • Kim, Kun-Hyung;Kim, Dong-Il;Hwang, Deok-Sang;Lee, Jin-Moo;Kim, Hyung-Jun;Yoon, Hyun-Min;Jung, Hee-Jung;Kang, Kyung-Won;Lee, Myeong-Soo;Choi, Sun-Mi
    • The Journal of Korean Obstetrics and Gynecology
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    • v.23 no.1
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    • pp.42-52
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    • 2010
  • Purpose: This report aims to administer methodologic issues around recently conducted multicenter study for evaluating the effects of acupuncture on menopusal hot flashes and discuss practical issues for further implementation of acupuncture clinical trial for hot flashes. Methods: Study process were mentioned, and issues related to avoiding risk of bias, designing appropriate control group, optimal outcome measurement, potential different effects of menopausal status on study outcomes, and suggestions for developing future clinical trials are discussed. Results: Shortcomings of our multicenter study include lack of allocation concealment and assessor blinding, subjective outcome measurement, short-term follow-up, and fixed acupuncture regimen despite pragmatic purpose of this study. Improving trial design, using objective or validated outcomes, assessing long-term effects of acupuncture, and individualizing acupuncture regimen are needed in future clinical trials. Conclusion: We expect these practical discussions to enable researchers to plan and develop future well-designed clinical trials for evaluating the effects of acupuncture on hot flashes or other women's health issues.

Enabling reuse driven software development : lessons learned from embedded software industry practice (재사용 기반의 소프트웨어 개발 체계 구축 : 내장형 소프트웨어 영역의 기업 사례)

  • Kim Kang-Tae
    • The KIPS Transactions:PartD
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    • v.13D no.2 s.105
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    • pp.271-278
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    • 2006
  • This paper presents industry feedback and a case of improvement trial on enabling reuse driven software development which is one of several activities to improve software quality and productivity in a company which develops software that are embedded into consumer electronic products. Several case studies will be introduced that are related to software reuse strategies and practices to show how to establish environment for reuse basis in a company, how to apply it to development team and project and how to improve that through trials and errors. To enable reuse-oriented software development in a huge company, integrated and focused approach is needed among technical, management and environmental point of view. We tried to solve that problem in technical field with reuse method, in management filed with reuse metric and in environment field with reuse repository. The characteristics of our software development environment could be summarized as below. The first, embedded software which would not independent to hardware devices and the second, it is very huge company which develops extremely various products by many different organization with different domain characteristics and the third, development lead time is extremely short and many variation models are stems from basic models. We expect that our study would give contribution to industry struggling to solve similar problem for presenting our experience and could be a reference model for enabling software reuse in a real world practically.

Construction Claims Prediction and Decision Awareness Framework using Artificial Neural Networks and Backward Optimization

  • Hosny, Ossama A.;Elbarkouky, Mohamed M.G.;Elhakeem, Ahmed
    • Journal of Construction Engineering and Project Management
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    • v.5 no.1
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    • pp.11-19
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    • 2015
  • This paper presents optimized artificial neural networks (ANNs) claims prediction and decision awareness framework that guides owner organizations in their pre-bid construction project decisions to minimize claims. The framework is composed of two genetic optimization ANNs models: a Claims Impact Prediction Model (CIPM), and a Decision Awareness Model (DAM). The CIPM is composed of three separate ANNs that predict the cost and time impacts of the possible claims that may arise in a project. The models also predict the expected types of relationship between the owner and the contractor based on their behavioral and technical decisions during the bidding phase of the project. The framework is implemented using actual data from international projects in the Middle East and Egypt (projects owned by either public or private local organizations who hired international prime contractors to deliver the projects). Literature review, interviews with pertinent experts in the Middle East, and lessons learned from several international construction projects in Egypt determined the input decision variables of the CIPM. The ANNs training, which has been implemented in a spreadsheet environment, was optimized using genetic algorithm (GA). Different weights were assigned as variables to the different layers of each ANN and the total square error was used as the objective function to be minimized. Data was collected from thirty-two international construction projects in order to train and test the ANNs of the CIPM, which predicted cost overruns, schedule delays, and relationships between contracting parties. A genetic optimization backward analysis technique was then applied to develop the Decision Awareness Model (DAM). The DAM combined the three artificial neural networks of the CIPM to assist project owners in setting optimum values for their behavioral and technical decision variables. It implements an intelligent user-friendly input interface which helps project owners in visualizing the impact of their decisions on the project's total cost, original duration, and expected owner-contractor relationship. The framework presents a unique and transparent hybrid genetic algorithm-ANNs training and testing method. It has been implemented in a spreadsheet environment using MS Excel$^{(R)}$ and EVOLVERTM V.5.5. It provides projects' owners of a decision-support tool that raises their awareness regarding their pre-bid decisions for a construction project.

FIRST ATLAS DOMESTIC STANDARD PROBLEM (DSP-01) FOR THE CODE ASSESSMENT

  • Kim, Yeon-Sik;Choi, Ki-Yong;Kang, Kyoung-Ho;Park, Hyun-Sik;Cho, Seok;Baek, Won-Pil;Kim, Kyung-Doo;Sim, Suk-K.;Lee, Eo-Hwak;Kim, Se-Yun;Kim, Joo-Sung;Choi, Tong-Soo;Kim, Cheol-Woo;Lee, Suk-Ho;Lee, Sang-Il;Lee, Keo-Hyoung
    • Nuclear Engineering and Technology
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    • v.43 no.1
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    • pp.25-44
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    • 2011
  • KAERI has been operating an integral effect test facility, ATLAS (Advanced Thermal-Hydraulic Test Loop for Accident Simulation), for accident simulations of advanced PWRs. Regarding integral effect tests, a database for major design basis accidents has been accumulated and a Domestic Standard Problem (DSP) exercise using the ATLAS has been proposed and successfully performed. The ATLAS DSP aims at the effective utilization of an integral effect database obtained from the ATLAS, the establishment of a cooperative framework in the domestic nuclear industry, better understanding of thermal hydraulic phenomena, and an investigation of the potential limitations of the existing best-estimate safety analysis codes. For the first ATLAS DSP exercise (DSP-01), integral effect test data for a 100% DVI line break accident of the APR1400 was selected by considering its technical importance and by incorporating comments from participants. Twelve domestic organizations joined in this DSP-01 exercise. Finally, ten of these organizations submitted their calculation results. This ATLAS DSP-01 exercise progressed as an open calculation; the integral effect test data was delivered to the participants prior to the code calculations. The MARS-KS was favored by most participants but the RELAP5/MOD3.3 code was also used by a few participants. This paper presents all the information of the DSP-01 exercise as well as the comparison results between the calculations and the test data. Lessons learned from the first DSP-01 are presented and recommendations for code users as well as for developers are suggested.

Developing Korean Learning Contents Using Augmented Reality (증강현실을 활용한 한국어 학습 콘텐츠 개발)

  • Park, Eunha;Jeon, Jinwoo
    • The Journal of the Korea Contents Association
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    • v.13 no.4
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    • pp.459-468
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    • 2013
  • With advancements in augmented reality technology, attempts to apply it in various fields have increased. With advancements in information technology and a growth in the number of Korean learners in Korea and abroad, there is a growing demand for state-of-the-art Korean learning contents. Because the Korean learning contents developed using augmented reality have been found insufficient, this paper investigates ways to develop better contents. This paper proposes ways to develop learning contents that can increase learners' interest in learning and lead to academic achievement, because the methods of education in Korea are limited to textbook learning and learning through the media. Because of the structure of fairytales and the educational lessons that can be learned from them, Korean learning contents are developed using fairytales. Additionally, Korean contents are designed to implement augmented reality technology, and learners need only have computers, webcams, and markers to make use of it. In consideration of Korean learners who do not have access to augmented reality technology, this paper clarifies that there should be a harmony between existing and new Korean learning contents. On the basis of this study, further studies on Korean education exploring the role of augmented reality should be conducted so that Korean learning contents that use diverse types of augmented reality technology can be will developed.

Success Factors of German Mittelstand as a Role Model for Korean Exporting SMEs (한국 수출중소기업 롤 모델로서 독일 미텔슈탄트의 성공요인 분석)

  • Hong, Song-Hon
    • International Commerce and Information Review
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    • v.15 no.4
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    • pp.341-366
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    • 2013
  • The term, Mittelstand, has no exact english translation for the definition, but, today, Mittelstand refers to small and medium-sized enterprises(SME), mostly family-owned firms in Germany. The Mittelstand is called the backbone of the German economy because it drove the economic miracle after World War II. During the global recession and the euro zone's debt crisis in recent years, in which european businesses have faced the near-collapse of competitiveness particularly in manufacturing, the German exports are booming and exceeded exports of China in 2012. Most importantly, the Germany economic performance has been widely attributed to the strength of the Mittelstand. Many of countries, even some leading public companies are seeking to emulate the success of the Mittelstand. Investors evaluate that many of Germany's investable "hidden champions" are Mittelstand companies. The purpose of this study is to present some of answers to the following questions: Firstly, what makes the German Mittelstand so successful? Secondly, what does the success of the German Mittelstand mean for the Korean SMEs in global competitiveness? Thirdly, what Korean government has to do improve the global competitiveness of the Korean SMEs? Some discussions in this study mention the managerial implications for Korean exporting SMEs particularly in manufacturing. Several factors that account for the success of the German Mittelstand are technological excellence and the tradition of family-owned management, concentration on niche market and globalization, and institutional supports. There are some of important lessons to be learned from the German Mittelstand. If the purposes of Korean SMEs want to remain in the sustainable competitive advantage and withstand unforeseen economic turbulences in the future, they must be able to meet the followings: 1) Technology that meets the global standard or exceeding it 2) Competitiveness in price in the global market 3) Active involvement in the globalization process, utilizing various entry modes Innovative products at globally competitive price are a crucial point for Korean exporting SMEs to achieve their competitive edge over others in the target markets abroad. It is time for Korean SMEs to cultivate a core competence in manufacturing in order to position Korea as a global manufacturing hub with SMEs leading.

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The Development of Risk Management Process Model during Bidding Phase for Success of Oversea Construction Projects (성공적 해외건설사업을 위한 입찰단계의 리스크 관리 프로세스 모델 개발 - 발전 플랜트 EPC 사업을 중심으로 -)

  • Seo, Jae-Pil;Ryu, Han-Guk;Son, Bo-Sik;Choi, Yoon-Ki
    • Korean Journal of Construction Engineering and Management
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    • v.17 no.4
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    • pp.76-86
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    • 2016
  • Recently, the Contracts of International Construction Business has been decreased from the beginning of 2015 in Korea, although it has been steadily increased until 2014. This trend could be caused by Low-Price Contracts, the lack of Know-how and experience in operating, the poor management of Claims and Low-Profitability in Business. It has been recognized that the qualitative improvement of Business Contacts are necessary for successful Projects. In the Bidding Process, therefore, Experience data as In-House Data and Lessons Learned for projects should be strategically involved to assure riskless offers. Accordingly the Proposal Process are needed to be organized and enhanced by including processes for risks review about technical, marketing and commercial part during the bidding. This paper proposes a Risk Management Process model during Bidding Phase, using Risk Evaluation Method through the project life-cycle. The Concept of Model is to define CSF (Critical Success Factor) in the bidding process and Risk Factors are linked to CSF and Organization based on RAM (Responsibility assignment matrix).