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Performance Prediction Model for Public-Private Partnership Projects Considering Stakeholders' Profitability (참여자별 수익성을 고려한 민간투자사업 성과예측 모델)

  • Yeo, Dong Hoon;Yu, Giwon;Lee, Kang-Wook;Han, Seung-Heon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.2
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    • pp.471-480
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    • 2015
  • The market of public-private partnership (PPP) projects has reduced from 9.4 trillion won in 2007 to 4.5 trillion won in 2012. However, the need of PPP projects is brought up by a massive down scale of government financial business. Previous studies regarding PPP projects mostly evaluate profitability from the financial perspective or analyze risk factors as a whole. Although PPP projects generally have complex structure involving diverse stakeholders, such as contractor, financial investor, and special purpose company (SPC) operators, existing studies have rarely considered the different viewpoints of PPP project stakeholders. Therefore, purpose of this study is to develop a structural equation model (SEM) considering the diverse stakeholders of PPP projects. To this end, the authors first reviewed the organizational structure of PPP projects. Next, the identification of the factors affecting project profitability are done via comprehensive literature reviews. After that, we conducted in-depth interviews and questionnaire surveys to reflect stakeholders' perspectives (contractors, financial investors, and SPC operators). As a result, a SEM model is developed to analyze direct and indirect effect on the PPP project performances. Finally, using the analysis results, relevant implications and directions for improvements are discussed. The prediction of the business performance of contractor, financial investor, and SPC operator is expect to be possible through the model developed and supports the strategy deduction that is appropriate for the participants.

Improvement of DeNOx efficiency of SNCR Process with Chemical Additives in Urea Soution (환원제로 우레아를 사용하는 SNCR 공정에서 첨가제 적용에 따른 탈질효율 향상 연구)

  • Yoo, Kyung Seun;Park, Sung Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.10
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    • pp.663-668
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    • 2017
  • Dye waste water generated in the dye industry is categorized as hazardous waste water that requires appropriate treatment. The pilot scale experimental trials were carried out using dye waste water as an effective additive for the selective non-catalytic reduction (SNCR) of NOx in combustion flue gases. The additives were waste liquor obtained from the dye industry and several purification steps were taken to make a standardized reagents. The dye waste water was shown to possess valuable SNCR qualities (at least 87% NOx reduction efficiency) considering its availability as a waste product, which has to be strictly treated, and have little effects on CO removal. The results indicated that the NO removal efficiency increased first and then decreased with increasing temperature within $750-1150^{\circ}C$. The maximum NO reduction efficiency was approximately 87% at the optimal reaction temperature. A more than 10% increase in NO reduction was achieved in the presence of 1000 ppm Na-additives (dye waste water) compared to that without additives. The Na-based additives have also a significant promoting effect on $N_2O$ reduction and within the SNCR temperature window.

Chromosomal Localization of Korean Cattle (Hanwoo) BAC Clones via BAC end Sequence Analysis

  • Chae, Sung-Hwa;Kim, Jae-Woo;Choi, Jae Min;Larkin, Denis M.;Everts-van der Wind, Annelie;Park, Hong-Seog;Yeo, Jung-Sou;Choi, Inho
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.3
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    • pp.316-327
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    • 2007
  • In this study, a Korean native cattle strain (Hanwoo) evidencing high performance in terms of both meat quality and quantity was employed in the generation of 150,000 BAC clones with an average insert size of 140 kb, and corresponding to about a 6X coverage of bovine chromosomal DNA. The BAC clones were pooled in a mini-scale via three rounds of a pooling protocol, and the efficiency of this pooling protocol was evaluated by testing the accuracy of accessibility to the positive clones, via a PCR-based screening method. Two sets of primers designed from each of two known genes were tested, and each yielded 2 or 3 positive clones for each gene, thereby indicating that the BAC library pooling system was appropriate with regard to the accession of the target BAC clones. Analyses of $3.3{\times}10^6$ base pairs obtained from the 7,090 BAC end sequence (BES) showed that 34.88% of the DNA sequence harbored the repetition sequence. Analysis of the 7,090 BES to the $1^{st}$ and $2^{nd}$ generation radiation hybrid map of the cattle genome, using the COMPASS program designed for the construction of a cattle-human comparative mapping, resulted in the localization of a total of 1,374 clones proximal to 339 $1^{st}$ generation markers, and 1,721 clones proximal to 664 $2^{nd}$ generation markers. Collectively, the BAC library and pooling system of the BAC clones from the Korean cattle, coupled with the chromosome-localized BAC clones, will provide us with novel tools for the excavation of desired clones for genome mapping and sequencing, and will also furnish us with additional information regarding breed differences in cattle.

Risk factor analysis of additional administration of sedative agent and patient dissatisfaction in intravenous conscious sedation using midazolam for third molar extraction

  • Shin, Dong-Whan;Cho, Jin-Yong;Han, Yoon-Sic;Sim, Hye-Young;Kim, Hee-Sun;Jung, Da-Un;Lee, Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.43 no.4
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    • pp.229-238
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    • 2017
  • Objectives: The primary purpose of this study was to investigate the factors related with additional administration of sedative agent during intravenous conscious sedation (IVS) using midazolam (MDZ). The secondary purpose was to analyze the factors affecting patient satisfaction. Materials and Methods: Clinical data for 124 patients who had undergone surgical extraction of mandibular third molar under IVS using MDZ were retrospectively investigated in this case-control study. The initial dose of MDZ was determined by body mass index (BMI) and weight. In the case of insufficient sedation at the beginning of surgery, additional doses were injected. During surgery, peripheral oxygen saturation, bispectral index score (BIS), heart rate, and blood pressure were monitored and recorded. The predictor variables were sex, age, BMI, sleeping time ratio, dental anxiety, Pederson scale, and initial dose of MDZ. The outcome variables were additional administration of MDZ, observer's assessment of alertness/sedation, intraoperative amnesia, and patient satisfaction. Descriptive statistics were computed, and the P-value was set at 0.05. Results: Most patients had an adequate level of sedation with only the initial dose of MDZ and were satisfied with the treatment under sedation; however, 19 patients needed additional administration, and 13 patients were unsatisfied. In multivariable logistic analysis, lower age (odds ratio [OR], 0.825; P=0.005) and higher dental anxiety (OR, 5.744; P=0.003) were related to additional administration; lower intraoperative amnesia (OR, 0.228; P=0.002) and higher BIS right before MDZ administration (OR, 1.379; P=0.029) had relevance to patient dissatisfaction. Conclusion: The preoperative consideration of age and dental anxiety is necessary for appropriate dose determination of MDZ in the minor oral surgery under IVS. The amnesia about the procedure affects patient satisfaction positively.

A Study on the Development of Creative and Cooperative Learning Spaces for University Libraries in Korea (국내 대학도서관 창의·협력 학습공간 조성에 관한 연구)

  • Jung, Youngmi;Lee, Eun-Ju
    • Journal of Korean Library and Information Science Society
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    • v.51 no.1
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    • pp.201-225
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    • 2020
  • In order to respond to changes in college's educational goals and talents, university libraries need to be transformed into spaces that support creative and collaborative learning. Apart from overseas cases, it is necessary to discuss the development of creative and collaborative learning spaces appropriate to the situation of Korean university libraries. This purpose of this study is to provide an effective guide to university libraries planning to develop creative and cooperative learning spaces. To this end, this study conducted a literature review to define the concept of a creative and collaborative learning space in a university library, collected and analyzed cases of creative and collaborative learning space of Korean university libraries, and proposed a model for developing creative and collaborative learning space for university library. Case collection was carried out through field visits to 12 university libraries. In addition, in-depth interviews were conducted with the staffs in charge of the construction and operation of five university libraries selected in consideration of the operating entity, region, and scale. This study is meaningful in that it intensively researched and analyzed the advanced cases of creative and collaborative learning spaces in Korea to derive suggestions that can be used in the field of domestic university libraries.

High-Temperature Structural-Analysis Model of Process Heat Exchanger for Helium Gas Loop (I) (헬륨가스루프 시험용 공정열교환기에 대한 고온구조해석 모델링 (I))

  • Song, Kee-Nam;Lee, Heong-Yeon;Kim, Yong-Wan;Hong, Seong-Duk;Park, Hong-Yoon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.9
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    • pp.1241-1248
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    • 2010
  • In large-scale production of hydrogen, a PHE (Process Heat Exchanger) is a key component because the heat required to carry out the Sulfur-Iodine chemical reaction that yields hydrogen is transferred from a VHTR (Very High Temperature Reactor) by the PHE. Korea Atomic Energy Research Institute established a helium gas loop for conducting performance test of components that are used in the VHTR. In this study, as a part of high-temperature structural-integrity evaluation of a designed PHE prototype that is scheduled to be tested in the helium gas loop, we carried out high-temperature structural-analysis modeling, thermal analysis, and thermal-expansion analysis for the designed PHE prototype. An appropriate constraint condition is proposed at the end of the in-flow and out-flow pipelines of the primary and secondary coolants and the proposed constraint condition will be applied to the design of the performance-test loop setup for the designed PHE prototype.

Modeling of the Failure Rates and Estimation of the Economical Replacement Time of Water Mains Based on an Individual Pipe Identification Method (개별관로 정의 방법을 이용한 상수관로 파손율 모형화 및 경제적 교체시기의 산정)

  • Park, Su-Wan;Lee, Hyeong-Seok;Bae, Cheol-Ho;Kim, Kyu-Lee
    • Journal of Korea Water Resources Association
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    • v.42 no.7
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    • pp.525-535
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    • 2009
  • In this paper a heuristic method for identifying individual pipes in water pipe networks to determine specific sections of the pipes that need to be replaced due to deterioration. An appropriate minimum pipe length is determined by selecting the pipe length that has the greatest variance of the average cumulative break number slopes among the various pipe lengths used. As a result, the minimum pipe length for the case study water network is determined as 4 m and a total of 39 individual pipe IDs are obtained. The economically optimal replacement times of the individual pipe IDs are estimated by using the threshold break rate of an individual pipe ID and the pipe break trends models for which the General Pipe Break Prediction Model(Park and Loganathan, 2002) that can incorporate the linear, exponential, and in-between of the linear and exponetial failure trends and the ROCOFs based on the modified time scale(Park et al., 2007) are used. The maximum log-likelihoods of the log-linear ROCOF and Weibull ROCOF estimated for the break data of a pipe are compared and the ROCOF that has a greater likelihood is selected for the pipe of interest. The effects of the social costs of a pipe break on the optimal replacement time are also discussed.

Main Features of Leather Armor from the Joseon Dynasty in the National Museum of Korea (국립중앙박물관 소장 조선시대 피갑(皮甲)의 특징에 관한 고찰)

  • Hwang, Jinyoung
    • Conservation Science in Museum
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    • v.20
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    • pp.61-76
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    • 2018
  • The National Museum of Korea conducted conservation treatmenton the armor in its collection for the purposes of public display and appropriate preservation. This was preceded by a literature study on the types and features of the armor in order to collect basic data for secure and accurate conservation treatment. The literature study found that during the Joseon dynasty, armor was named in reflection of precise details including the color, material, status of the wearer, and even the certain parts of a suit of armor. In general, the name of armor includes the details in the order of color, underlying textile, and scale material (e.g., iron, leather). The former part of the name presents the features of the garment and the latter part refers to the material of the scales or the status of the wearer. The study also found that main materials used in armor include textiles, leather, and metal, and armor can be classified by the materials of the scales-e.g., metal armor (鐵甲), leather armor (皮甲), paper armor (紙甲), paper-and-fabric armor (淹心甲), silk armor (緞甲). Joseon-period armor can also be classified into four types according to its structure and the method of wearing, and overcoat(袍)-style armor was the most widely used in the period following the Japanese Invasion of Joseon (1592-1598) through the late nineteenth~early twentieth century. Overcoat-style armor was commonly worn by infantry, and the four examples of armor with leather scales at the National Museum of Korea belong to this category.

A Valuation for Gas Hydrate R&D Project Using Fuzzy Real Options Model (퍼지실물옵션모형을 이용한 가스하이드레이트 R&D 사업의 가치평가)

  • Yun, Ga-Hye;Heo, Eunnyeong
    • Environmental and Resource Economics Review
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    • v.18 no.2
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    • pp.217-239
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    • 2009
  • As gas hydrate is recently emerging as a new energy source to solve environmental and exhaustion problems caused by fossil energy, Korea is working on a gas hydrate development project under a 10-year plan from 2005 to 2014. Gas hydrate is expected to have a big effect on the economy and society of Korea, which is largely depending on energy imports besides water energy and atomic energy. However, it is uncertain whether the project will produce successful results. Thus, it is very important to improve its validity and to propose effective execution strategies by evaluating the value of the project in advance. Thus, this study intended to include new information, which had not been evaluated in existing methods, and to reduce biases or errors in value evaluation results by applying a fuzzy risk analysis to the real option model in order to evaluate the value of a gas hydrate development project. It is advantageous that the real option model based on the fuzzy risk analysis modelizes the vagueness and inexactness of intangible element judgment into an appropriate language scale so as to evaluate these elements clearly and integrate them with estimated financial performance results. The application of the fuzzy risk analysis makes it possible to conduct an analysis by dissolving a decision-making issue with complicated and various attributes into several simplified problems. With the continuing high oil prices and today's demand of clean energy, the necessity of energy resources and technology development projects keeps growing. Amid this situation, it is expected that these study results will contribute to proposing a guideline not only for gas hydrate projects but also for policy decision-making related to future energy industries.

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Impact Assessment of Sea_Level Rise based on Coastal Vulnerability Index (연안 취약성 지수를 활용한 해수면 상승 영향평가 방안 연구)

  • Lee, Haemi;Kang, Tae soon;Cho, Kwangwoo
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.27 no.5
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    • pp.304-314
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    • 2015
  • We have reviewed the current status of coastal vulnerability index(CVI) to be guided into an appropriate CVI development for Korean coast and applied a methodology into the east coast of Korea to quantify coastal vulnerability by future sea_level rise. The CVIs reviewed includes USGS CVI, sea_level rise CVI, compound CVI, and multi scale CVI. The USGS CVI, expressed into the external forcing of sea_level rise, wave and tide, and adaptive capacity of morphology, erosion and slope, is adopted here for CVI quantification. The range of CVI is 1.826~22.361 with a mean of 7.085 for present condition and increases into 2.887~30.619 with a mean of 12.361 for the year of 2100(1 m sea_level rise). The index "VERY HIGH" is currently 8.57% of the coast and occupies 35.56% in 2100. The pattern of CVI change by sea_level rise is different to different local areas, and Gangneung, Yangyang and Goseong show the highest increase. The land use pattern in the "VERY HIGH" index is dominated by both human system of housing complex, road, cropland, etc, and natural system of sand, wetland, forestry, etc., which suggests existing land utilization should be reframed in the era of climate change. Though CVI approach is highly efficient to deal with a large set of climate scenarios entailed in climate impact assessment due to uncertainties, we also propose three_level assessment for the application of CVI methodology in the site specific adaptation such as first screening assessment by CVI, second scoping assessment by impact model, and final risk quantification with the result of impact model.