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Comparative Study on Monetary Estimates of Natural Environment and Cultural Relics in Gyeongju National Park (경주국립공원의 문화유적과 자연환경의 가치추정 비교연구)

  • Kang, Kee-Rae;Kim, Dong-Pil;Baek, Jae-Bong
    • Korean Journal of Environment and Ecology
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    • v.26 no.2
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    • pp.273-282
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    • 2012
  • This study has estimated Gyeongju National Park's natural environment and cultural relic value in the same way and then been performed to compare the size of the value. Representative method to measure environmental property is contingent valuation methods, CVM. The variables and estimated models adopted for the calculation were same and the respondents were asked by distinguishing between the amount which they would pay to preserve the natural environment and that which they were willing to pay to preserve the cultural relics. As the result, WTP(Willing to pay), the amount that they were willing to pay to preserve the natural environment of Gyeongju National Park was 17,838 won per person and that to preserve the cultural relics appeared to be 316,248 won per person. Based on this, it was estimated that the value of the natural environment with which Gyeongju National Park provided annual visitors was 47 billion won and that the annual value of the cultural relics was 845.7 billion. If the natural environment and the cultural relics value elements are united, it can be estimated that the natural environment and cultural relic value got at the time of people's first visit to Gyeongju National Park is 334,086 won and that the annual value is 893.4 billion won. In this study, the value of the cultural relics has been estimated 18 times higher than that of the natural environment. This reason was that visitors judged that a total of 66 cultural properties including 11 national treasures, 23 treasures, 13 historic places, one historic sites and scenic spot and 18 local cultural properties, etc. which were distributed in Gyeongju National Park were worth far more than the natural environment. Based on the result of this study, the operating management plan of Gyeongju National Park should include a differentiated operation strategy through consultation with relevant experts by taking into account characteristics of the physical components.

A Dynamic Behavior Evaluation of the Curved Rail according to Lateral Spring Stiffness of Track System (궤도시스템의 횡탄성에 따른 곡선부 레일의 동적거동평가)

  • Kim, Bag-Jin;Choi, Jung-Youl;Chun, Dae-Sung;Eom, Mac;Kang, Yun-Suk;Park, Yong-Gul
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.517-528
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    • 2007
  • Domestic or international existing researches regarding rail damage factors are focused on laying, vehicle conditions, driving speed and driving habits and overlook characteristics of track structure (elasticity, maintenance etc). Also in ballast track, as there is no special lateral spring stiffness of track also called as ballast lateral resistance in concrete track, generally, existing study shows concrete track has 2 time shorter life cycle for rail replacement than ballast track due to abrasion. As a result of domestic concrete track design and operation performance review, concrete track elasticity is lower than track elasticity of ballast track resulting higher damage on rail and tracks. Generally, concrete track has advantage in track elasticity adjustment than ballast track and in case of Europe, in concrete track design, it is recommended to have same or higher performance range of vertical elastic stiffness of ballast track but domestically or internationally review on lateral spring stiffness of track is very minimal. Therefore, through analysis of service line track on site measurement and analysis on performance of maintenance, in this research, dynamic characteristic behaviors of commonly used ballast and concrete track are studied to infer elasticity of service line track and experimentally prove effects of track lateral spring stiffness that influence curved rail damage as well as correlation between track elasticity by track system and rail damage to propose importance of appropriate elastic stiffness level for concrete and ballast track.

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A Clinical Study for Gall Bladder Stones in Children (소아 담석증에 대한 임상적 연구)

  • Eun, Ho Seon;Baek, Seoung Yon;Chung, Ki Sup
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.8 no.2
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    • pp.194-201
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    • 2005
  • Purpose: Gall bladder (GB) stones in children are rarely observed, and so reports of them have been quite limited in Korea. Therefore, we tried to assess the epidemiology and clinical features of children with GB stone diagnosed at Severance Hospital. Methods: A clinical study was performed on 18 patients below 15 years of age diagnosed with GB stone by abdominal ultrasonography or CT scan at Severance hospital from January 1999 to May 2005. Results: Concerning patients' profile, their sex ratio of male to female in total 18 cases was 2 : 1 with the mean age of $6{\pm}4.3years$. 15 patients (83.3%) were asymptomatic. Inducing factors were found in 14 children (77.8%) including ceftriaxone therapy in 6 cases (33.3%), infection in 4 cases (22.2%), spherocytosis in 3 cases (16.7%), Down syndrome and abdominal operation in 1 case (5.6%) respectively. Single stone was found in 13 cases (76.5%) and multiple in 4 cases (23.5%). 15 cases (88.2%) had the stones less than 5 mm in size, and 2 cases (11.8%) between 5 and 10 mm. 17 patients received conservative treatment, and one patient had cholecystectomy due to Meckel diverticulum. Conclusion: In this report, Pediatric GB stones are predominant in male children, without typical symptoms, having inducing factors, single and small. Recently the diagnosis of them has been increased because of the development of imaging study. But the reports for them were still rare in Korea. Therefore the study for them is more necessary to find it's clinical characteristics.

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A Study on their Health Promotion Behavior Influenced by Primary School Students' Self-concept (초등학생의 자아개념이 건강증진행위에 미치는 영향)

  • Lee, Deog-Weon;Park, Young-Soo
    • The Journal of Korean Society for School & Community Health Education
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    • v.1 no.2
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    • pp.29-48
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    • 2000
  • This study was designed to diagnose the correlations between health promotion behavior and primary school students' demographic characteristics and their self-concept, and also this study was aimed at representing the basic data of proper instruction method and school health program with the respective to primary school students' health promotion behavior through the above things. For this, author selected as 5th, 6th graders, 400 persons at 5 elementary schools located on Kyonggi province. This data utilized ANOVA, multiple regression analysis and correlation analysis by SPSS program. The findings of this study were as follows; First, there showed meaningful differences concerning their health promotion behavior according to students' demographic traits. There were a birth date, living standard, domestic environments etc. as a factors which influenced on their health promotion behavior. With this, from ex-past-facto verification for these variable factors, as their birth date was faster, living standard was higher, domestic environments was better, as their health promotion behavior was more promotive. Second, students' health promotion behavior marked 3.61 among total 5 paint with the respective to its fulfillment degree, their self-concept marked 3.45 among total 5 paint. Their mental health promotion behavior marked 3.71 with the respective to inferior category of health promotion behavior, which was the highest score. In the other hands, their physical health promotion behavior marked 3.71, social health promotion behavior marked 3.45. contrary the disease prevention, first-aid & safety, oral health, health & nutrition(P>.05). Third, there show meaningful difference, in the level of p-value <.001 with the respective to the correlations between primary school students' health promotion behavior and their self-concept, more their self-concept was positive, more their more their whole health promotion behavior(r=.479), the fulfillment degree of physical health promotion behavior(r=.384), mental health promotion behavior(r=.543), social health promotion behavior(r=.372) were high. Fourth, with the respective to the results of difference verification concerning their fulfillment degree of health promotion behavior according to the upper, middle, inferior group of self-concept, there showed statistically meaningful difference, in the level of p-value<.001. In the long run, more their self-concept was positive, more their whole health promotion behavior was high. With this, from the results of $Scheff\acute{e}$ verification, there showed meaning differences among the upper and middle group, upper and inferior group, middle and inferior group. Fifth, self-concept played the role as the most important prognostic factor with the respective to primary school students' health promotion behavior(23.0%), in the other hands, there showed positive weight of 24.0% concerning the fulfillment of whole health promotion behavior by domestic environments(1.0%). From the above results, primary school students' the fulfillment degree of health promotion behavior didn't reach to middle or inferior level. In the other hands, there showed positive effects in the correlations between self-concept and the fulfillment degree of health promotion behavior, and also high self-concept group was much positive considering inferior group in the fulfillment degree of health promotion behavior. Accordingly, more their self-concept was positive, more their fulfillment degree of health promotion behavior was effective. Eventually, in the future, there have to make an efforts to develope positive, substantial programs through their self-concept enhancement etc. in the adequate planning or operation for primary school students' health education and school health program.

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Clinical Analysis of Pleuropneumonectomy for Chronic Inflammatory Lung Disease (만성염증성 폐질환에서 전폐절제술의 임상적 평가)

  • Choi Pil-Jo;Bang Jung-Heui;Kim Si-Ho;Cho Kwang-Jo;Woo Jong-Soo
    • Journal of Chest Surgery
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    • v.39 no.6 s.263
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    • pp.462-469
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    • 2006
  • Background: Pneumonectomy for inflammatory lung disease has been of major concern because of its associated morbidity and mortality, particularly with respect to pleuropneumonectomy. The purpose of this study is to evaluate the surgical outcomes, and identify the risk factors contributing to postoperative complications in patients undergoing pleuropneumonectomy. Material and Method: Ninety-eight patients underwent pneumonectomy for benign inflammatory lung disease were retrospectively analyzed. Pleuropneumonectomy (Group A) was done in 48 patients and standard pneumonectomy (Group B) was done in 50 patients. Clinical characteristics, postoperative complications were examined and compared between 2 groups. In pleuropneumonectomy group, postoperative risk factors affecting morbidity were evaluated. Result: There was one in-hospital death. Twenty-three major postoperative complications occurred in 21 patients (21.4%). The common complications were empyema and bronchopieural fistula (BPF) in 8 (8.4%), re-exploration due to bleeding in 8. At least one postoperative complication occurred in 14 of 48 patients from Group A (29.2%) and in 7 of 50 patients from Group B (14%). In Group A, empyema and BPF encountered in 6 and re-exploration for bleeding in 6 were the most common complication. In univariate analysis, right pneumonectomy, completion pneumonectomy, large amount of blood loss (>1,000 mL), and intrapleural spillage were risk factors contributing to postoperative complications in Group A. In multivariate analysis, intrapleural contamination during operation was a risk factor of postoperative complication. Conclusion: The morbidity and mortality rates of pneumonectomy for chronic inflammatory lung disease are acceptably. However, we confirm that pleuropneumonectomy is a real technical challenge and a high-risk procedure and technically demanding. Meticulous surgical techniques are very important in preventing serious and potentially lethal complications.

Mid-Term Results of Mitral Valve Repair Using a Partial Flexible Band and a Completely Rigid Ring in Patients with Degenerative Mitral Regurgitation (퇴행성 승모판막역류 환자에서 Partial Flexible Band와 Complete Rigid Ring을 이용한 승모판막 성형술의 중기 결과 비교)

  • Kim, Kyung-Hwan;Ahn, Hyuk;Hwang, Ho-Young;Choi, Jin-Ho;Kim, Ki-Bong
    • Journal of Chest Surgery
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    • v.43 no.5
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    • pp.475-481
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    • 2010
  • Background: We evaluated mid-term results of mitral annuloplasty using a flexible band and a completely rigid ring for mitral valve repair in patients with degenerative mitral regurgitation (MR). Material and Method: From January 2004 to September 2008, 71 patients (M:F=36:35, $55{\pm}13$ years) underwent mitral valve repair with mitral annuloplasty for degenerative MR. Ring annuloplasty was done using a Cosgrove-Edwards flexible band (Group I, n=43) or a Carpentier-Edwards classic ring (Group II, n=28). There were no differences in preoperative characteristics of the participants. Average duration of follow-up was 36 months (range: 2~69 mos). Result: There was no in-hospital mortality. Postoperative morbidity, which included atrial fibrillation (n=7) and low cardiac output syndrome (n=5) in groups I and II were similar. There was one late death in group II. The proportion exhibiting freedom from recurrent mitral regurgitation ($\geq$moderate) at 4 years in Groups I and II were, respectively, 94.5 and 91.8%, (p=0.695). Left ventricular ejection fraction decreased in the early postoperative period ($7{\pm}2$ days) and recovered by last follow-up ($25{\pm}16$ mos; p=0.002). The pattern was similar in groups I and II (p=0.905). Re-operation was performed in 3 patients (1 in Group I and 2 in Group II, p=0.316). Four-year event-free survival (free of adverse valve-related events) was 95.2% for Group I and 92.6% for Group II; this difference was not significant, p=0.646). Conclusion: The type of technique used in mitral annuloplasty to repair the mitral valve repair after degenerative MR did not affect mid-term clinical and functional results.

Entry Types and Locational Determinants of North Korean Workers in Cross-border Regions between North Korea and China (중국 대북 접경지역의 북한 노동력 진입 유형과 요인)

  • Lee, Sung-Cheol;Lee, Yong-Hee;Kim, Boo-Heon
    • Journal of the Economic Geographical Society of Korea
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    • v.22 no.4
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    • pp.438-457
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    • 2019
  • The main purpose of this paper is to identify the entry types and locational determinants of North Korean workers in cross-border regions between North Korea and China. More specifically, the paper has attempted to divide the entry type of them in the regions into two; 1) entry via transactions between Chinese traders with North Korea and North Korea trade companies, and 2) entry via transactions between Korean-Chinese middlemen and North Korean trade companies. Also, it has analyzed main factors of their locational determinants in the spatial contexts of the regions. There have been changes in two perspectives in terms of the entry paths and types of them in accordance with the transformation of characteristics of United Nations sanction against North Korea from 'call-upon' to 'decide' after UN Security Council Resolution 2094 in 2013. Firstly, main agents who have dealing with North Korean trade companies which have right to dispatch North Korean workers have been changed from Chinese traders into Korean-Chinese brokers who are specialized in the introduction of North Korean workers with one-stop service from visa administrative to labor managements. Secondly, there has been a transfer of North Korean workers in the regions from formal to informal workers who has been admitted into China with a short stay or a tourist visa, and then remained illegally to be employed in China. Therefore, as demands on service which is able to guarantee the security of North Korean informal workers and their managements have increased, Korean-Chinese brokers have been stimulated in the regions after the operation of real international sanctions against overseas North Korean workers. In addition, the main factors of their locational determinants in cross-border regions between North Korea and China are could be analyzed in three perspectives; 1) an increase in real wages in accordance with the reform of the Chinese social insurance system after 2011, 2) the structural vulnerability of labor markets in the regions, 3) the utilization of stable and manageable workers.

Fate of Heavy Metals in Activated Sludge: Sorption of Heavy Metal ions by Nocardia amarae

  • Kim, Dong-wook
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 1998.10a
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    • pp.2-4
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    • 1998
  • Proliferation of Nocardia amarae cells in activated sludge has often been associated with the generation of nuisance foams. Despite intense research activities in recent years to examine the causes and control of Nocardia foaming in activated sludge, the foaming continued to persist throughout the activated sludge treatment plants in United States. In addition to causing various operational problems to treatment processes, the presence of Nocardia may have secondary effects on the fate of heavy metals that are not well known. For example, for treatment plants facing more stringent metal removal requirements, potential metal removal by Nocardia cells in foaming activated sludge would be a welcome secondary effect. In contrast, with new viosolid disposal regulations in place (Code o( Federal Regulation No. 503), higher concentration of metals in biosolids from foaming activated sludge could create management problems. The goal of this research was to investigate the metal sorption property of Nocardia amarae cells grown in batch reactors and in chemostat reactors. Specific surface area and metal sorption characteristics of N. amarae cells harvested at various growth stages were compared. Three metals examined in this study were copper, cadmium and nickel. Nocardia amarae strain (SRWTP isolate) used in this study was obtained from the University of California at Berkeley. The pure culture was grown in 4L batch reactor containing mineral salt medium with sodium acetate as the sole carbon source. In order to quantify the sorption of heavy metal ions to N amarae cell surfaces, cells from the batch reactor were harvested, washed, and suspended in 30mL centrifuge tubes. Metal sorption studies were conducted at pH 7.0 and ionlc strength of 10-2M. The sorption Isotherm showed that the cells harvested from the stationary and endogenous growth phase exhibited significantly higher metal sorption capacity than the cells from the exponential phase. The sequence of preferential uptake of metals by N. amarae cells was Cu>Cd>Ni. The specific surFace area of Nocardia cells was determined by a dye adsorption method. N.amarae cells growing at ewponential phase had significantly less specific surface area than that of stationary phase, indicating that the lower metal sorption capacity of Nocardia cells growing at exponential phase may be due to the lower specific surface area. The growth conditions of Nocardia cells in continuous culture affect their cell surface properties, thereby governing the adsorption capacity of heavy metal. The comparison of dye sorption isotherms for Nocardia cells growing at various growth rates revealed that the cell surface area increased with increasing sludge age, indicating that the cell surface area is highly dependent on the steady-state growth rate. The highest specific surface area of 199m21g was obtained from N.amarae cell harvested at 0.33 day-1 of growth rate. This result suggests that growth condition not only alters the structure of Nocardia cell wall but also affects the surface area, thus yielding more binding sites of metal removal. After reaching the steady-state condition at dilution rate, metal adsorption isotherms were used to determine the equilibrium distributions of metals between aqueous and Nocardia cell surfaces. The metal sorption capacity of Nocardia biomass harvested from 0.33 day-1 of growth rate was significantly higher than that of cells harvested from 0.5- and 1-day-1 operation, indicatng that N.amarae cells with a lower growth rate have higher sorpion capacity. This result was in close agreement with the trend observed from the batch study. To evaluate the effect of Nocardia cells on the metal binding capacity of activated sludge, specific surface area and metal sorption capacity of the mixture of Nocardia pure cultures and activated sludge biomass were determined by a series of batch experiments. The higher levels of Nocardia cells in the Nocardia-activated sludge samples resulted in the higher specific surface area, explaining the higher metal sorption sites by the mixed luquor samples containing greater amounts on Nocardia cells. The effect of Nocardia cells on the metal sorption capacity of activated sludge was evaluated by spiking an activated sludge sample with various amounts of pre culture Nocardia cells. The results of the Langmuir isotherm model fitted to the metal sorption by various mixtures of Nocardia and activated sludge indicated that the mixture containing higher Nocardia levels had higher metal adsorption capacity than the mixture containing lower Nocardia levels. At Nocardia levels above 100mg/g VSS, the metal sorption capacity of activate sludge increased proportionally with the amount of Noeardia cells present in the mixed liquor, indicating that the presence of Nocardia may increase the viosorption capacity of activated sludge.

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A Study on Perception on Development about Han River Citizen Parks according to Leisure Constraints (여가제약에 따른 한강시민공원 여가공간개발에 대한 인식연구)

  • Kim, Hyeon-Jee;Lee, Yong-Hak;Kang, Eun-Jee;Kim, Yong-Geun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.42 no.5
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    • pp.52-63
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    • 2014
  • This is the study on users' perception gap about the effects of leisure space development of the Han River Citizen Park according to leisure constraints and was to identify leisure constraints expressed when using Han River Citizen Park and identify perception on positive and negative impacts according to use behavior characteristics of Han River Citizen Park and leisure space development. In order to compare and analyze the perception gap about the leisure space development of Han River Citizen Park users according to leisure constraints, we classified information and resources, economic affordability, free time on leisure activities in Han River Citizen Park into high influence group and low influence group and did an in-depth analysis. The results are as follows. First, Han River Citizen Park has the nature of neighborhood use with little influence on leisure constraints such as jogging and marathon, biking etc. including walking and relaxation and was a place to visit for simple exercises. Second, in the effects according to leisure space development of Han River Citizen Park, affordable leisure activity costs and ease of access were evaluated the most highly and congestion due to increasing users, increase in administrative operating budget and management personnel were concerned the most. Third, the leisure constraints in Han River Citizen Park were affected in the order of free time, economic affordability, information and resources. There were also perception gaps in congestion due to an increase in administrative operating budget and management personnel, increase in users including improvement of various leisure opportunities and leisure levels, encouragement of pride and attachment for Han river, affordable leisure activity costs depending on the degree of the influence of leisure constraints. Therefore, this study can be said to have the meaning in that we could identify leisure constraints affecting Han River Citizen Park users and resulting perception in leisure space development and revealed that the degree of the influence of leisure constraints varies in the use behavior of leisure space development of Han River Citizen Park and perception of positive and negative development impact. In addition, in order to resolve leisure complaints according to leisure constraints, we studied the need of accompaniment of leisure space operation and management system, development of various customized programs, introduction of recreational space and facilities prioritizing public interest rather than private interest with public relations and information delivery about leisure space of Han River Citizen Park.

An Analysis of Process-oriented Design in the Invited Entries of International Competition for the Master Plan of the Yongsan Park, Korea (용산공원 설계 국제공모 출품작에 나타난 프로세스적 설계 분석)

  • So, Jin;Sung, Jong-Sang;Pae, Jeong-Hann
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.2
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    • pp.11-26
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    • 2013
  • Designing large parks such as Yongsan Park requires the open-ended process-oriented design approach in complex layers rather than the conventional self-completed master plan method. This study aims to examine the characteristics of process-oriented design in the eight invited entries of "International Competition for the Master Plan of the Yongsan Park, Korea"(2012). For this purpose, it analyzed each entry according to three criteria: objects of process-oriented approach, time factor and its features of phasing plan, and presentation method of the process. This analysis can not only critically review the current level of the process-centered design methodology but also suggest strategic future directions for Yongsan Park. The objects of process-oriented design in the eight works were order of physical space development, restoration process of ecosystem, recovering process of publicity, and economic operation and management. Main considerations in the objects were connections to adjacent urban fabrics, links to regional green and water system, reuse of existing buildings and infrastructures in the site. The temporal criteria of the phasing plan had two aspects. One was planning a certain time and period, and the other was just establishing an order of phases. Most of the presentation method of process was the phasing plan, but some of the entries suggested a scenario plan. The eight works of "International Competition for the Master Plan of Yongsan Park" did not attempt process-oriented designs entirely and completely. Rather, they tried to introduce the phasing plan as part of a process-centered design. Also, they took an eclectic approach between master plan and process-oriented design instead of rejecting the conventional master plan approach.