• Title/Summary/Keyword: Review Study

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A Review Study on Major Factors Influencing Chlorine Disappearances in Water Storage Tanks (저수조 내 잔류염소 감소에 미치는 주요 영향 인자에 관한 문헌연구)

  • Noh, Yoorae;Kim, Sang-Hyo;Choi, Sung-Uk;Park, Joonhong
    • Journal of Korean Society of Disaster and Security
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    • v.9 no.2
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    • pp.63-75
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    • 2016
  • For safe water supply, residual chlorine has to be maintained in tap-water above a certain level from drinking water treatment plants to the final tap-water end-point. However, according to the current literature, approximately 30-60% of residual chlorine is being lost during the whole water supply pathways. The losses of residual chlorine may have been attributed to the current tendency for water supply managers to reduce chlorine dosage in drinking water treatment plants, aqueous phase decomposition of residual chlorine in supply pipes, accelerated chlorine decomposition at a high temperature during summer, leakage or losses of residual chlorine from old water supply pipes, and disappearances of residual chlorine in water storage tanks. Because of these, it is difficult to rule out the possibility that residual chlorine concentrations become lower than a regulatory level. In addition, it is concerned that the regulatory satisfaction of residual chlorine in water storage tanks can not always be guaranteed by using the current design method in which only storage capacity and/or hydraulic retention time are simply used as design factors, without considering other physico-chemical processes involved in chlorine disappearances in water storage tank. To circumvent the limitations of the current design method, mathematical models for aqueous chlorine decomposition, sorption of chlorine into wall surface, and mass-transfer into air-phase via evaporation were selected from literature, and residual chlorine reduction behavior in water storage tanks was numerically simulated. The model simulation revealed that the major factors influencing residual chlorine disappearances in water storage tanks are the water quality (organic pollutant concentration) of tap-water entering into a storage tank, the hydraulic dispersion developed by inflow of tap-water into a water storage tank, and sorption capacity onto the wall of a water storage tank. The findings from his work provide useful information in developing novel design and technology for minimizing residual chlorine disappearances in water storage tanks.

Effect of University Students' Perceived Organizational Support and Employment Preparation Activities for their Awareness of Good Job (대학생의 조직지원인식과 취업준비활동이 좋은 일자리 인식에 미치는 영향)

  • Bea, Sung-Sook;Chang, Sug-In
    • Management & Information Systems Review
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    • v.36 no.1
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    • pp.59-80
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    • 2017
  • Due to the recent deepening youth unemployment aftereffect, government, companies and universities seek a youth unemployment resolution method and jobs creating measures. But there are indications that the Good Job the university students prefer are limited and sudden rise of the youth unemployment rate mirrors the situation in Japan 20 years ago. Thus, based on the preceding research, this research attempted to perform comparative analysis on Korean and Japanese university students' employment preparation activities and perceived organizational support affect their Awareness of Good Job. To achieve the goal, 2013 GOMS 5,380 copies provided by Korea Employment Information Service are used in the case of Korea and total 5,636 copies within 256 questionnaires targeted to Japanese university students are used in the case of Japan. The results of analysis are as follows. The effect relationship between the perception of organizational support and awareness of Good Job showed a positive influence both in Korea and Japan. The effect relationship between employment preparation activities and awareness of Good Job showed a meaningful effect in Korea whereas it showed no effect in Japan. In the relationship between activities of employment preparation and awareness of Good Job, moderating effect of gender and major field of study didn't show any effect either in Korea or Japan. The results of this research are as follows. First, because it is verified that the support of university has positive influence on the university students' awareness of Good Job, it seems that universities need to intensify the support for the students' welfare enhancement, education satisfaction and the structural support system. Second, the gap of attitude of employment preparation activities and awareness of Good Job between Korea and Japan occurred due to the levels of social structure, welfare and wage differences in the two countries. Therefore, if measures of policy to resolve the welfare and wage gaps between conglomerates and smaller enterprises are enacted, the awareness of younger generations to the Good Job will show a corresponding effect.

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Domestic and International Experts' Perception of Policy and Direction on STEAM Education (융합인재교육(STEAM)의 정책과 실행 방향에 대한 국내외 전문가들의 인식)

  • Jung, Jaehwa;Jeon, Jaedon;Lee, Hyonyong
    • Journal of Science Education
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    • v.39 no.3
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    • pp.358-375
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    • 2015
  • The purposes of this study were to investigate the value, necessity and legitimacy of STEAM Education and to propose practical approaching methods for STEAM Education to be applicable in Korea through a variety of literature review, case studies and collecting suggestions from domestic and international educational experts. The research questions are as follows: (1) To investigate the perception, understanding and recognitions of domestic and foreign professionals in STEAM education. (2) To analyze policy implications for an improvement in STEAM. The following aspects of STEAM were found to be challenges in our current STEAM policy after analyzing multiple questionnaires with the professionals and case studies including their experiences, understanding, supports and directions of the policy from the governments. The results indicate that (1) there was a lack of precise and conceptual understanding of STEAM in respect to experience. Training sessions for teachers in this field to help transform their perception is necessary. Development of practical programs with an easy access is also required. It is important to get the aims of related educational activities recognized by the professionals and established standards for an evaluation. The experts perceived that a theme-based learning is the most preferred and effective approaching method and the programs that develop creative thinking and learning applicable to practice are required to promote. (2) The results indicate that there was a lack of programs and inducements for supporting outstanding STEAM educators. It is shown that making an appropriate environment for STEAM education takes the first priority before training numbers of teachers unilaterally, thus securing enough budget seems critical. The professionals also emphasize on developing specialized teaching materials that include diverse inter-related subjects such as science technology, engineering, arts and humanities and social science with diverse viewpoints and advanced technology. This work requires a STEAM network for teachers to link up and share their materials, documents and experiences. It is necessary to get corporations, universities, and research centers participated in the network. (3) With respect to direction, it is necessary to propose policy that makes STEAM education ordinary and more practical in the present education system. The professionals have recommended training sessions that help develop creative thinking and amalgamative problem-solving techniques. They require reducing the workload of teachers and changing teachers' perspectives towards STEAM. They further urge a tight cooperation between departments of the government related with STEAM.

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Development of Korean Healthy Eating Index for adults using the Korea National Health and Nutrition Examination Survey data (국민건강영양조사 자료를 이용한 한국 성인의 식생활평가지수 개발)

  • Yook, Sung-Min;Park, Sohee;Moon, Hyun-Kyung;Kim, Kirang;Shim, Jae Eun;Hwang, Ji-Yun
    • Journal of Nutrition and Health
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    • v.48 no.5
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    • pp.419-428
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    • 2015
  • Purpose: The current study was conducted in order to develop the Korean Healthy Eating Index (KHEI) for assessing adherence to national dietary guidelines and comprehensive diet quality of healthy Korean adults using the 5th Korea National Health and Nutrition Examination Survey (KNHANES) data. Methods: The candidate components of KHEI were selected based on literature reviews, dietary guidelines for Korean adults, 2010 Dietary Reference Intakes for Koreans (2010 KDRI), and objectives of HP 2020. The associations between candidate components and risk of obesity, abdominal obesity, and metabolic syndrome were assessed using the 5th KNHANES data. The expert review process was also performed. Results: Diets that meet the food group recommendations per each energy level receive maximum scores for the 9 adequacy components of the index. Scores for amounts between zero and the standard are prorated linearly. For the three moderation components among the total of five, population probability densities were examined when setting the standards for minimum and maximum scores. Maximum scores for the total of 14 components are 100 points and each component has maximum scores of 5 (fruit intakes excluding juice, fruit intake including juice, vegetable intakes excluding Kimchi and pickles, vegetable intake including Kimchi or pickles, ratio of white meat to read meat, whole grains intake, refined grains intake, and percentages of energy intake from carbohydrate) or 10 points (protein foods intake, milk and dairy food intake, having breakfast, sodium intake, percentages of energy intake from empty calorie foods, and percentages of energy intake from fat). The KHEI is a measure of diet quality as specified by the key diet recommendations of the dietary guidelines and 2010 KDRIs. Conclusion: The KHEI will be used as a tool for monitoring diet quality of the Korean population and subpopulations, evaluation of nutrition interventions and research.

A Study on Design Techniques of Palace Gardens presented in Donggwoldo (동궐도에 보이는 궁궐정원의 조영수법)

  • Chin, Sang-Chul
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.33 no.4
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    • pp.26-37
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    • 2015
  • This paper aims to review all landscaping elements of Donggwoldo by building and identify the palatial garden landscaping characteristics and landscaping methods in a bid to explore landscaping methods applicable for modern-time gardens of Korea through Succession of Tradition. The research methodology was adopted by which the palatial gardens appearing in Donggwoldo were observed according to garden elements to identify their characteristics. Garden elements in Donggwoldo include oddly shaped stones, ponds, buildings and Madang, borders and areas, and trees. Their characteristics were analyzed, and as a result they are outlined as follows. Location : Buildings in Donggwoldo were located in the optimal areas within the Myungdang (the best location), with the building sites being created by transforming the natural topography positively according to the existing topography and uses. Tree planting : The construction of the buildings involved using the existing trees. There were no specific principle and method of planting trees, and no specific criteria for choosing the kind of tree. Symmetrical planting was adopted and its is considered embracing the viewpoint of making gardens based on the expression of Yin and Yang. Strongly symbolical kinds of trees were also adopted. Bangji : it takes a nearly circular shape in palatial gardens, and such shapes represent conceptual and abstract symbols. They were also frequently used as the place of public entertainment. Pavilions : they did not take a certain standard shape. They had diverse shapes, including a triangle, square, pentagon, hexagon, and octagon and cross. Oddly shaped stones : Oddly shapes stones and stone cases were deployed mainly near the bedroom and the crow prince's residence and in the rear garden. Hwagye : it appeared mainly in the back of the bedroom, the crown prince's residence, the princess's residence, and other women's quarters. Chwibyeong : it was installed for the purpose of drawing the natural energy like a natural inlet instead of being the nature-dividing wall. Korea's garden composition method was very different from the Western and Chinese method. Overall, Chosun palatial garden style was characterized by strict and Confucian features, while the garden construction method adopted the Taoism thought. Yet, the gardens had a carefree aspect.

A Clinical Characteristics of Systemic Candidiasis in Neonatal Intensive Care Unit : Comparison with Systemic Bacterial Infection (신생아 집중치료실 입원아에 있어서 전신성 칸디다증의 임상적 특징 : 전신성 세균 감염증과 비교)

  • Lim, Jung Hwa;Park, Kyung Pil;Kim, Jin Kyung;Kim, Heng Mi
    • Clinical and Experimental Pediatrics
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    • v.45 no.7
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    • pp.847-854
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    • 2002
  • Purpose : Long term hospitalized infants in neonatal intensive care units(NICUs) are prone to systemic infection. It is important to differentiate systemic candidiasis from systemic bacterial infection early in the course. Thus, in this study, we have compared clinical characteristics of systemic candidiasis and systemic bacterial infection, in premature low birth weight infants. Methods : Retrospective chart review of the medical records of 20 patients with systemic candidiasis and 23 patients with systemic bacterial infection was performed. Results : Among the risk factors of systemic candidiasis, total parenteral nutrition(TPN), the use of broad spectrum antibiotics, central catheter insertion, endotracheal intubation and the use of H2 blockers were more frequent in neonates with systemic candidiasis than neonates with systemic bacterial infection. Apnea with bradycardia developed more frequently in neonates with systemic candidiasis compared with systemic bacterial infection(75% vs 39%). In laboratory findings at symptom onset, seven cases(35%) of systemic candidal infections and two cases(9%) of systemic bacterial infections showed leukopenia and thrombocytopenia(P=0.03). Blood was the most frequent isolation site of candida and bacteria. Conclusion : In neonates with systemic candidiasis, apnea with bradycardia, pneumonia and thrombocytopenia were prone to develop more frequently. The use of TPN, antibiotics and central catheters was strongly associated with systemic candidiasis. Empirical treatment with antifungal agent should be considered in critically ill neonates with above findings.

Clinical implication of Dendritic Cell Infiltration in Cervical Tuberculous Lymphadenitis (결핵성 경부 림프절염에서 수지상돌기세포의 침윤과 임상양상의 연관성)

  • Jung, Jae Woo;Lee, Young Woo;Choi, Jae Cheol;Yoo, Seung Min;Lee, Hwa Yeon;Lim, Seoung Young;Shin, Jong Wook;Kim, Jae Yoel;Park, In Whn;Kim, Mi Kyung;Choi, Byoung Whui
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.5
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    • pp.523-531
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    • 2006
  • Background : Cervical tuberculous lymphadenopathy is a very common disease with a similar incidence to pulmonary tuberculosis. Dendritic cells play a role of initial antigen presentation of this illness. Nevertheless, the precise role of these antigen-presenting cells according to the clinical features in unclear. The aim of this study was to determine the clinical implication of dendritic cell infiltration in the cervical lymph nodes. Methods : A review of the clinical characteristics was carried out retrospectively based on the clinical records and radiography. Immunohistochemical staining was performed on the available histology specimens of 72 cases using the S-100b polyclonal antibody for dendritic cells. The number of dendritic cells with tuberculous granuloma were determined. A $X^2$ test, unpaired T test and multiple logistic regression analysis were performed. Results : Thirty percent of subjects had previous or concurrent pulmonary TB. Twenty one percent of cases showed a positive reaction on the AFB stain. Within a granuloma, the number of infiltrated dendritic cells was $113.0{\pm}7.0$. The incidence of fever and cough decreased with increasing infiltration of dendritic cells Multivariate regression analysis showed that the infiltration of dendritic cells could significantly contribute to fever. Conclusion : Overall, dendritic cells can control a Mycobacterium tuberculosis infection and modulate the immune response, as well as resolve the clinical manifestations of TB lymphadenopathy.

The Impact of Organizational Internal IT Capability on Agility and Performance: The Moderating Effect of Managerial IT Capability and Top Management Championship (기업 내적 IT 자원이 기업 민첩성과 성과에 미치는 영향: 관리적 IT 능력과 경영진 존재의 조절효과)

  • Kim, Geuna;Kim, Sanghyun
    • Information Systems Review
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    • v.15 no.3
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    • pp.39-69
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    • 2013
  • Business value of information technology has been the biggest interest of all such as practitioners and scholars for decades. Information technology is considered as the driving force or success factor of firm agility. The general assumption is that organizations making considerable efforts in IT investment are more agile than the organizations that are not. However, IT that should help the strategies of the firm that can hinder business or impede agility of the firm occasionally. In other words, it is still unknown if IT helps the agility of the firm or bothers it. Therefore, we note that contrary aspects of IT such as promotion and hindrance of firm agility have been observed frequently and theorize the relationships between them. In other words, we propose a rationale that firms should need to develop superior firm-wide IT capability to manage IT resources successfully in order to realize agility. Thus, this paper theorizes two IT capabilities, including technical IT capability and managerial IT capability as key factors impacting firm agility and firm performance. Further, we operationalize firm agility into two sub-types, including operational adjustment agility and market capitalizing agility. The data from 171 firms was analyzed using PLS approach. The results showed that technical IT capability has positive impact on firm agility and managerial IT capability had positive moderating effects between technical IT capability and firm agility. In addition, it was identified that top management championship positively moderates between agility and firm performance. Finally, it was indicated that firm agility was a very important causal variable of firm performance. Our study provides more exquisite and practical empirical evidences in the relationship between IT capability and firm agility by proposing applicable solution although IT has some contradicting effects on firm agility. Our findings suggest many useful implications to agility related researches in relatively primitive stage and working level officers in organizations.

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Prognostic Value and Histologic Correlation of Sonography in Childhood Nephrotic Syndrome (신증후군 환아에서 신장초음파의 예후적 가치 및 조직검사와의 상관관계에 대한 연구)

  • Cheon Hae-Won;Yoo Kee-Hwan;Hong Young-Sook
    • Childhood Kidney Diseases
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    • v.2 no.1
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    • pp.26-33
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    • 1998
  • This retrospective study was designed to evaluate the prognostic value and histologic correlation of sonography in childhood nephrotic syndrome. Sixty-nine patients with proteinuria over 2g per day at the time of presentation who were treated at the Korea University Hospital were included in this review. They were 1 to 15 years old(mean age, 7.8 years) with 49 males and 20 females. In each patient an ultrasound examination was done using SPA 1000(Diasonics, C.A., U.S.A.) on admission. Tissue specimens were obtained from 46 patients. The paraffin-embedded specimens were reviewed with special reference to interstitial edema, interstitial fibrosis, tubular atrophy, global sclerosis or inflammatory cell infiltrates. Biopsy proven renal disease were minimal change disease(n=20), focal segmental glomerulosclerosis(n=7), membranous glomerulonephritis(n=2), membranoproliferative glomerulonephritis(n=1), $Henoch-Sch\"{o}nlein$ purpura nephritis(n=6), IgA nephropathy(n=5), poststreptococcal glomerulonephritis(n=2), systemic lupus erythematosus(n=1) and Alport syndrome(n=2). There was a significant relationship between increased cortical echogenicity and global sclerosis or tubular atrophy(P<0.05). But no significant relationship was found between increased cortical echogenicity and interstitial fibrosis, interstitial edema, or inflammatory cell infiltration. In biopsy-proven primary nephrotic syndrome(n=30), no significant relationship was found between the increased conical echogenicity and the interstitial edema, interstitial fibrosis, global sclerosis, tubular atrophy or inflammatory cell infiltration. But there was a significant relationship between increased cortical echogenicity and resistance to corticosteroid (P<0.05). These results suggest that increased cortical echogenicity may be due to tubular atrophy or global sclerosis in patients with proteinuria and may be an effective indicator of resistance to corticosteroid in primary nephrotic syndrome.(J Korean Soc of Pediatr Nephrol 2:26-33, 1998)

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A Study on the Legal Explanation and Cases of Remedies for Breach of Contract by the Buyer under CISG (CISG하에서 매수인의 계약위반에 대한 매도인의 구제수단에 관한 고찰 - CISG 제3편 제3장 제3절(제61조 내지 제65조)의 규정해석과 판결례를 중심으로 -)

  • Shim, Chong-Seok
    • International Commerce and Information Review
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    • v.14 no.3
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    • pp.231-251
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    • 2012
  • The remedies available to a seller that has suffered a breach of contract by the buyer are addressed in Section III of Chapter III of Part III. The first provision in the section, 61, catalogues those remedies and authorizes an aggrieved seller to resort to them. The remaining provisions of the section address particular remedies or prerequisites to remedies. The subject matter of the current section remedies for breach of contract by the buyer obviously parallels that of Section III of Chapter II of Part III remedies for breach of contract by the seller. Many individual provisions within these sections form matched pairs. Thus 61, which catalogs the seller's remedies, which catalogs the buyer's remedies. Other provisions in the current section that have analogues in the section on buyer's remedies include 62, seller's right to require buyer's performance 63, seller's right to fix an additional period for buyer to perform and 64, seller right to avoid the contract. As was the case with the provisions on buyers' remedies, the articles governing sellers' remedies operate in conjunction with a variety of provisions outside the current section. Thus the seller's right to require performance by the buyer is subject to the rule in 28 relieving a court from the obligation to order specific performance in circumstances in which it would not do so under its own law. The authorization in 61 for a seller to claim damages for a buyer's breach operates in connection with 74-76, which specify how damages are to be measured. 49, stating when an aggrieved seller can avoid the contract, is part of a network of provisions that address avoidance, including the definition of fundamental breach, the requirement of notice of avoidance, provisions governing avoidance in certain special circumstances, measures of damages available only if the contract has been avoided and the provisions of Section V of Part III, Chapter V on effects of avoidance.

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