• Nuclear Engineering and Technology
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• v.26 no.3
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• pp.440-452
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• 1994

Nuclear fuel bundles are designed such that the heat flux at a-fuel pin surface should not exceed the critical heat flux (CHF) during normal operation and anticipated transient. Therefore, evaluation of the CHF for fuel bundle is demanded in an exact and reliable manner. One of the major concerns with the current application of CHF correlations is that the CHF based on circular tubes is applied to the fuel bundle subchannel analysis, mainly in terms of the hydraulic diameter with correction factors which may result in a source of possibly large uncertainties in CHF prediction. The hydraulic diameter does not recognize the local properties of fluid nor such effect as the surface curvature; the turbulence action on the convex surface is much more pronounced than that on the concave surface. Even for the tube having concave curvature, the effect of tube diameter on CHF becomes important with decreasing diameter. These facts imply that the convex curvature effect is significant and crucial to the reliable CHF prediction. This paper reviews and discusses analytical and experimental aspects of effect of transverse convex curvature in incompressible turbulent flow and heat transfer, and on CHF. Flow models to quantify this effect are briefly mentioned and future works are recommended.

• Journal of the Korean Geographical Society
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• v.49 no.2
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• pp.113-138
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• 2014

Despite the growing numbers of regional problems (e.g. conflicts between the state and localities, inter-local conflicts, etc.) associated with the state-led developmental projects, the Korean social sciences have been unable to offer satisfying explanations and solutions to the regional problems. This is mainly because the existing works, which have been taken captured by the assumptions of "methodological nationalism", significantly lack the socio-spatial understandings of the state actions and the relations between the state and localities, thereby seeing the issues of regional development mainly in terms of either the economic efficiency defined at the national scale, or the plan rationality of the national bureaucrats. With this problem orientation in mind, this paper aims to explore the ways in which the state and localities are interacting, conflicting and negotiating with one another through the mediation of the state-led developmental projects. Focusing on the developmental processes of Masan Export Processing Zone from the mid-1960s to the early 1970s, it examines the multi-scalar processes through which the state-led industrial complex developmental processes have been influenced by the complex and dynamic interactions among social forces and actors acting at diverse geographical scales (e.g. the global, national, local, urban, etc.). This analysis shows that the regional policies of the Korean developmental state were more heavily influenced by the interactions, contestations, and collaborations among social forces and actors, acting in and through the state, at various geographical scales, rather than by the economic and techno-bureaucratic rationality.

• Journal of the Korean Geographical Society
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• v.39 no.3
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• pp.344-359
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• 2004

This geographical study is to identify the reality of Nokdun island which was once settled and farmed by our ancestor, but currently the island is do facto under Russia's control. Various historical documents including old maps, current large scale maps and satellite images besides field work were used for full analysis. According to historical records, up until Chosun Dynasty, Nokdun island in the lower Tuman river was one of the frontier fortified base crossed the river for the northern defense as well as seasonal farming for the farmer of Kyounghung border area. Even though the island was unjustly lost to Russia by the Beijing Treaty in the late Chosun period, the whole area of Nokdun was occupied and farmed by sole Koreans until the deportation by Stalin was forcibly measured. In these days due to the change of Tumn river channel and new deposition by river it became very difficult to find the original shape of Nokdun island. However, through intensive field works based on historical records, the research team found out the existence of the old wet-dry fields, old rural farmhouse remnants, and small and medium size of millstones that are supporting the reality of the island. Especially, the team traced a mud fortress presumedly built in the early Chosun period. We believe it might allow to allocate the exact location of Nokdun island in near future.

• Journal of Radiation Protection and Research
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• v.32 no.1
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• pp.27-34
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• 2007

In this paper, We are evaluated about bio-signal between general workers and nuclear medicine workers which is more radiation exposure relatively. In order to reciprocal evaluated two group, we experimented nuclear medicine workers in Chung-Buk National University Hospital at department of nuclear medicine and worker in Chon-Nam National University Hospital at CT room, general radiographic room, medical recording room, receipt room, general office room. Used of experimental Equipments as follows, for a level of radiation measurement by pocket dosimeter which made by Arrow-Tech company, for heart rate and blood pressure measurement by TONOPORT V which made by GE medical systems company, for heat flux and skin temperature and energy expenditure measurement by Armband senseware 2000 which made by Bodymedia company. Result of experiment obtains as follows: 1) Individual radiation exposure is recorded 3.05 uSv at department of nuclear medicine and order as follows CT room, general radiograpic room, medical recording room, receipt room, general office room. Department of nuclear medicine more 1.5 times than other places. 2) Radiation accumulated dose is not related to Heat flux, Skin temperature, Energy expenditure. 3) Blood pressure is recorded equal to nuclear medical workers, general officer, general people about systolic blood pressure and diastolic blood pressure. Compared to blood pressure between nuclear medical works which is more radiation exposure and other workers was not changed. Consequently, more radiation exposed workers at nuclear medicine field doesn't have hazard.

• Spatial Information Research
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• v.18 no.4
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• pp.23-32
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• 2010

Water mains underground facilities are essential components to make up urban infrastructure. In order to manage these water mains underground facilities systematically and scientifically, GIS (Geographic Information System) had been constructed. For the sake of construction of GIS for water mains underground facilities, an exact underground detection and the construction of DB (Data Base) for buried water mains underground facilities should be preceded. In this study, in order to find out the ways to improve exact detection rate of data, the statistical analysis for the causes of detection raw degradation was done, and standardization methods of detection through a case study were suggested, When water mains underground facilities were measured, the detection of non-metallic water pipes was not carried out. The reason was that the results of detection was uncertain and detection was difficult because the assessment of public measurements was vulnerable. Moreover, due to the absence of standardized operating regulations for detection, systematic surveys weren't conducted. In this study, methods to standardize works over the detection of water mains underground facilities were presented so that we can improve the detection rate when we are doing that. As the proposals to improve detection rate, effective performance assessment over non-metallic pipes were presented, and related issues to supplement work regulations of public survey were described systematically.

• Information Systems Review
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• v.11 no.1
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• pp.49-67
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• 2009

E-mail marketing is the cheapest channel in target marketing. The channel works amazingly well for marketers who know how to use it. The e-mail marketers are able to integrate transactional and behavioral data to improve the targeting content of e-mail marketing campaigns. The cost in e-mail marketing is low and e-mail marketing makes no pollution. But, the e-mail response rate is lower than all the other channels. So, it is very hard for companies to increase their sales volumes, though the companies are ready to execute e-mail marketing campaigns on the side of computer systems. Marketers can send messages easily to target customers compared to other channels. But, the possibility to be read by the customers is low. Normal e-mails are continually devalued by spam mails. This study shows the influence of e-mail marketing to increase sales used by credit cards, on the basis of the real data promoted by A bank, in the Republic of Korea. The analysis on the traits of the respondent can help marketers to target customers. If additional studies on the response prediction model on the basis of traits of potential respondents are done, the targeting method to increase the effectiveness of e-mail marketing will be better structured and organized.

• Korean Journal of Construction Engineering and Management
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• v.12 no.4
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• pp.59-69
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• 2011

Construction works have become larger and more complex, improving productivity by introducing Information Technology (IT) is pursued. In this circumstance, many different kinds of project management system is being introduced, and various IT technologies are applied such as Personal Digital Assistant (PDA), Bar Code, Radio Frequency Identification (RFID), Web Camera, and so on. However, these kinds of technologies might cause reprocessing of information and ineffectiveness of project because of lack of real time information processing technology or separation between construction sites and management offices. Therefore, this research aims to develop Application that can be applied efficiently for construction material management, by understanding problems of former management system with questionnaires and extracting functions with analysis of requirements. This will be possible to input information automatically, to process and check material information in real time, and to identify the location of necessary material. Then, the problem of separation between construction sites and management offices are solved, and as a result, more efficient management of materials in construction sites will become possible.

• Science of Emotion and Sensibility
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• v.8 no.3
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• pp.221-229
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• 2005

This study aimed to understand the sex differences in cognitive behaviors in website design and demonstrate a practical basis for utilizing these differences into more user-centered design concept. Especially, we focused on the sex-different preference according to the information architecture of website navigation. First, We investigated general differences between men and women in cognitive behaviors through various literature studies. According to our investigation, men's cognitive works generally tend to follow a regular sequence and proceed step by step. On the other hand, women's cognitive style is generally characterized by random generation and simultaneous progress. To examine that these differences can be found in use of website navigation, we made an experiment in website design. We designed several test websites that have same contents but different style of navigation structure. A similar number of men and women were chosen for this test and they implemented given tasks. During the test, participants reported their preference on each websites and their implementing time and number of errors were collected. Based on the analysis of test data, it was possible to conclude that male participants' preference for the navigation with a narrow and deep information structure is relatively higher than female participants' preference for the same navigation, On the other hand, female participants have a preference of the navigation with a broad and swallow information structure. The result of study showed that there is a close correlation between the sex differences in preference of navigation types and the general sex differences in cognitive behavior. This finding can be used as a basis for designing the website navigation in which sex differences are reflected.

• Magazine of the Korea Concrete Institute
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• v.6 no.4
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• pp.113-122
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• 1994

To examine the applicabilty of the converter furnace slag from iron-works as concrete aggregate respective concrete furnace slag with contents of 20%. 40%, 60%. 80% were mixed with granulated slag, and the strength and stability tests for these specimens were followed. The slump value of the concrete mixed with converter furnace slag was higher than that of the conventional concrete. Furnace slag and granulated slag was increased as the increase of converter furnace content. The strength of the concrete mixed with converter furnace slag and granulate slag increased as an increase of converter furnace content and age. The expansion rate of the concrete mixed with converter furnace slag and granulated slag increased from 0.007% to 0.19% as the converter furnace content changed from 20% to 80%. From the above results in the strength and expansion rate, the concrete with the converter furnace content of 40% was considered to be recommandable for the stable construction of the concrete. Calculated formulas for tensile strength(${\sigma}_t$) and flexural strength(${\sigma}_f$) from the regression a.nalysis of the correlations among these compressive strength (${\sigma}_c$), tensile strength and flexural strength are as follows. ${\sigma}_t$ = 0.16952${\sigma}_c$ - 4.9313 ${\sigma}_f$ = 0.25727${\sigma}_c$ + 6.0528

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.5
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• pp.13-25
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• 2008

Although competitions for large parks are increasing rapidly across the world, theoretical research and critiques of these competitions are as yet insufficient. The 'International Design Competition for Central Open Space in Multi-functional Administrative City, Korea', a representative competition for large park design, can be a significant resource for examining the contemporary design strategies that go into the design of a large park. In this study, the authors make a framework for analysis by looking at the competition's design guidelines and literatures on 'large parks', and by then analyzing the ten finalists. Four questions that were derived from the framework were: 'what are the approaches to large parks?', 'what is the process of design?', 'what is the sustainability of the park?', and 'what are the relations between city and park?' The results of the study are as follows. First, the design concepts for large parks are primarily site-specific. It is particularly important in ensuring the identity of the large park. Second, it is difficult to find design proposals which satisfy the four main questions sufficiently, and works submitted tend to be visual-oriented, form-oriented, and results-centered. Third, the notion of 'sustainability' in large parks is a comprehensive one which includes various aspects such as ecology, finance, programming, and community. However, the notion remains ambiguous, and plans for operation and management are not concretely proposed. Finally, design proposals for large parks accompany positive relations with the city. Especially, 'productive parks' and 'city self-sufficiency' are very important demands in regards to large parks.