• 제목/요약/키워드: Depth of focus

검색결과 823건 처리시간 0.027초

A View from the Bottom: Project-Oriented Risk Mining Approach for Overseas Construction Projects

  • Lee, JeeHee;Son, JeongWook;Yi, June-Seong
    • 국제학술발표논문집
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    • The 6th International Conference on Construction Engineering and Project Management
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    • pp.97-100
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    • 2015
  • Analysis of construction tender documents in overseas projects is a very important issue from a risk management point of view. Unfortunately, majority of construction firms are biased by winning contracts without in-depth analysis of tender documents. As a result, many contractors have incurred loss in overseas projects. Although a lot of risk analysis techniques have been introduced, most of them focus project's external unexpected risks such as country conditions and owner's financial standing. However, because those external risks are difficult to control and take preemptive action, we need to concentrate on project inherent risks. Based on this premise, this paper proposes a project-oriented risk mining approach which could detect and extract project risk factors automatically before they are materialized and assess them. This study presents a methodology regarding how to extract potential risks which exist in owner's project requirements and project tender documents using state of the art data analysis method such as text mining, data mining, and information visualization. The project-oriented risk mining approach is expected to effectively reflect project characteristics to the project risk management and could provide construction firms with valuable business intelligence.

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Review on tidal stream energy and blade designs for tropical site conditions and a look at Philippines' future prospects

  • Mark Anthony Rotor;Hamid Hefazi;Nelson Enano, Jr.
    • Ocean Systems Engineering
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    • 제13권3호
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    • pp.247-268
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    • 2023
  • Tidal stream energy extraction remains a site-specific resource due to the "first generation" criteria requiring high-velocity tidal streams. Most studies on tidal energy and turbine blade design heavily focus on installation sites with higher velocity conditions that are non-existent in tropical countries such as the Philippines. To shorten this gap, this review paper tackles tidal turbine design considerations for low-energetic regions such as the tropics. In-depth discussions of operating principles, methods of analysis, and designs of tidal turbine blades are presented. Notable tidal stream projects around the world are also mentioned in the paper. Also, it provides a perspective on the potential of this renewable energy to produce electricity for various sites in the Philippines. Finally, the paper emphasizes the need for new tidal turbine blade designs to be viable in tropical regions, such as the Philippines.

이용자관점에서 본 아이돌보미지원사업의 특성과 개선방안에 관한 기초연구 (A Basic Study on Public Nanny Service Characteristics and Improvement Strategies)

  • 이승미;김선미
    • 대한가정학회지
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    • 제49권4호
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    • pp.51-65
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    • 2011
  • In order to find out better policy strategies for public nanny service, this study tried to find out the characteristics and the major problems of this service based on 24 in-depth interviews and 7 focus group interviews with nannies, beneficiaries, managers, and public agents. Research findings showed that public nanny service was effectively filling the gap between nursery care services and parent's care services(especially who are both working). Also, this service provided tailored support to parents who have urgent or unexpected problems which prohibit them from properly caring their children. Especially this service effectively worked for temporary needs of caring young children. This study proposes these two strategies as follows: First, the beneficiary selection criteria should be updated. Second, the level and types of available time should be raised to fit the diverse needs of parents.

국가바람지도 및 국가지리정보에 의한 국내 해상풍력단지 개발계획의 비교분석 (Review on The Proposed Offshore Wind Farm Projects Using National Wind Atlas and National Geographic Information)

  • 김현구;황효정
    • 한국태양에너지학회 논문집
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    • 제30권5호
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    • pp.44-55
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    • 2010
  • The proposed offshore wind farm projects, i.e., Mooudo offshore, Yeonggwang-Gochang offshore, Saemangeum offshore, Imjado offshore and Gadeokdo-Dadeapo offshore, were compared and analyzed using the Korea National Wind Mapand Wind Farm Suitability Assessment System developed by the Korea Institute of Energy Research. The suitability of the proposed areas was comprehensively assessed using geographic, economic constraints, wave condition and wind resource factors, but the focus of this paper was on the geographic constraints and wave conditions. Imjado had several geographical constraints, despite having a good wind power density, while Saemangeum had a relatively low wave height, shallow water depth, close substation and slow tidal current. It is anticipating that the present comparison and analysis could be used as reference guidelines when selecting and preparing the design of large-scale offshore wind farm in the near future.

Ceramic Stereolithography: Additive Manufacturing for 3D Complex Ceramic Structures

  • Bae, Chang-Jun;Ramachandran, Arathi;Chung, Kyeongwoon;Park, Sujin
    • 한국세라믹학회지
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    • 제54권6호
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    • pp.470-477
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    • 2017
  • Ceramic processing to fabricate 3D complex ceramic structures is crucial for structural, energy, environmental, and biomedical applications. A unique process is ceramic stereolithography, which builds ceramic green objects from CAD files from many thin liquid layers of powder in monomer, which are solidified by polymerization with a UV laser, thereby "writing" the design for each slice. This approach directly writes layers in liquid ceramic suspension and allows one to fabricate ceramic parts and products having more accurate, complex geometries and smooth surfaces. In this paper, both UV curable materials and processes are presented. We focus on the basic material principles associated with free radical polymerization and rheological behavior, cure depth and broadening of cured lines, scattering at ceramic interface and their corresponding simulation. The immediate potentials for ceramic AM to change industry fabrication are also highlighted.

Building Green Entrepreneurship: A Journey of Environmental Awareness to Green Entrepreneurs in Thailand

  • Tesprasit, Kornthong;Aksharanandana, Pakatip;Kanchanavibhu, Athikom
    • Journal of Information Technology Applications and Management
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    • 제27권5호
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    • pp.35-47
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    • 2020
  • Global waste has become a global issue and we can see the new trend of discovery businesses established to focus on solving the waste problem using new renewable energy technology and the circular economy business model. This paper aims to study factors that impact green entrepreneurship in Thailand, such as environmental concern, organizational environment, founder demographics, education background, entrepreneurship awareness, as well as external factors of a business. The study analyzes the data from three qualitative in-depth interviews with green entrepreneur founders who started the businesses in polymer up-cycling, waste management, and renewable energy. The study finds overseas educational background to be one of the key main drivers for the entrepreneurial courage to decide to pursue a new business venture. By having the exposure toward the different culture, three entrepreneurs hands-on experiential learning through three key drivers who are composed of the can-do attitude, the willingness to be self-employed, and the way of seeking for the freedom to express their passions.

Color Cosmetics Market's Segmentation for Korean New Seniors

  • Baek, Kyoung Jin
    • 한국의류학회지
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    • 제44권6호
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    • pp.1189-1204
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    • 2020
  • Population aging and longevity have compelled major worldwide consumer markets to focus on senior citizens who exhibit a desire to nurture their appearance and obtain related products such as cosmetics. This trend signals an increasing need for in-depth research on elderly consumers in the color cosmetics market. This study identified the characteristics of seniors in the pre-elderly stage ("new seniors") based on their lifestyle and market segments. It employed online surveys with participants consisting of pre-elderly Korean women born between 1955 and 1963 who reside in the greater Seoul and Gyeonggi area. The study used SPSS 23.0 for factor analysis, reliability verification, cluster analysis, ANOVA, Duncan's test, and cross-analysis. The results show that new seniors could be classified into four groups based on lifestyle: Prime Seniors, Potential Seniors, Rational Seniors, and Slump Seniors. Each group has distinct characteristics. The findings suggest that the senior market requires further segmentation and is no longer a single uniform market. This study also confirms that the lifestyles of the elderly is an instrumental variable for their segmentation.

Data Mining Research on Maehwado Painting Poetry in the Early Joseon Dynasty

  • Haeyoung Park;Younghoon An
    • Journal of Information Processing Systems
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    • 제19권4호
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    • pp.474-482
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    • 2023
  • Data mining is a technique for extracting valuable information from vast amounts of data by analyzing statistical and mathematical operations, rules, and relationships. In this study, we employed data mining technology to analyze the data concerning the painting poetry of Maehwado (plum blossom paintings) from the early Joseon Dynasty. The data was extracted from the Hanguk Munjip Chonggan (Korean Literary Collections in Classical Chinese) in the Hanguk Gojeon Jonghap database (Korea Classics DB). Using computer information processing techniques, we carried out web scraping and classification of the painting poetry from the Hanguk Munjip Chonggan. Subsequently, we narrowed down our focus to the painting poetry specifically related to Maehwado in the early Joseon Dynasty. Based on this, refined dataset, we conducted an in-depth analysis and interpretation of the text data at the syllable corpus level. As a result, we found a direct correlation between the corpus statistics for each syllable in Maehwado painting poetry and the symbolic meaning of plum blossoms.

마이크로 레이저 평면빔을 이용한 마이크로채널 내에서의 Micro-LIF 측정 (Micro-LIF Measurement in a Micro-channel Using an Micro Laser Light Sheet)

  • 윤상열;김재민;김수헌;김경천
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.1540-1545
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    • 2004
  • Measurement of concentration fields in a micro-channel is the crucial technology in the area of Lab-on-a-chip to be used for various bio-chemical applications. It is wel-known that the only possible way to measure the concentration field in the micro-channel is using micro-LIF(Laser Induced Fluorescence) method. However, an accurate concentration field at a given cross plane in a micro-channel has not been made so far due to the limit of light illumination. The present study demonstrates a novel method to provide an ultra thin laser sheet beam having 5 microns thickness by a micro focus laser line generator. Nile Blue A was used as fluorescent dye for LIF measurement. The laser sheet beam illuminates an exact plane of concentration measurement in the micro-channel to increase the signal to noise ratio and reduce the depth uncertainty considerably.

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음향방출을 이용한 버 유형 분류 (Burr Classification Using Acoustic Emission)

  • 김필재;이성환
    • 한국정밀공학회지
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    • 제19권2호
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    • pp.133-139
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    • 2002
  • A number of experimental studies on burr formation in face milling operations have been pursued. They usually focus on machining parameters such as depth of cut, leed rate, spindle speed and in-plane exit angle. But it if difficult to set the correlation between burrs and the parameters on burr when such parameters are considered at the same time. Therefore, in this paper, acoustic emission (AE) is considered as an alternate way to predict burr types regardless of machining conditions. AE signals during face milling were sampled and processed, then fed into an artificial neural network to classify burr types \\\"on-line\\\".\\\".uot;.