• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.6
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• pp.521-537
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• 2012

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2011. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of fluid machinery and fluid flow, thermodynamic cycle, and new and renewable energy. Various topics were presented in the field of fluid machinery and fluid flow. Research issues mainly focused on the rankine cycle in the field of thermodynamic cycle. In the new and renewable energy area, researches were presented on geothermal energy, fuel cell, biogas, reformer, solar water heating system, and metane hydration. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer, nanofluids and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer above liquid helium surface in a cryostat, methane hydrate formation, heat and mass transfer in a liquid desiccant dehumidifier, thermoelectric air-cooling system, heat transfer in multiple slot impinging jet, and heat transfer enhancement by protrusion-in-dimples. In the area of pool boiling and condensing heat transfer, researches on pool boiling of water in low-fin and turbo-B surfaces, pool boiling of R245a, convective boiling two-phase flow in trapezoidal microchannels, condensing of FC-72 on pin-finned surfaces, and natural circulation vertical evaporator were actively performed. In the area of nanofluids, thermal characteristics of heat pipes using water-based MWCNT nanofluids and the thermal conductivity and viscosity were measured. In the area of industrial heat exchangers, researches on fin-tube heat exchangers for waste gas heat recovery and Chevron type plate heat exchanger were implemented. (3) Refrigeration systems with alternative refrigerants such as $CO_2$, hydrocarbons, and mixed refrigerants were studied. Heating performance improvement of heat pump systems were tried applying supplementary components such as a refrigerant heater or a solar collector. The effects of frost growth were studied on the operation characteristic of refrigeration systems and the energy performance of various defrost methods were evaluated. The current situation of the domestic cold storage facilities was analyzed and the future demand was predicted. (4) In building mechanical system fields, a variety of studies were conducted to achieve effective consumption of heat and maximize efficiency of heat in buildings. Various researches were performed to maximize performance of mechanical devices and optimize the operation of HVAC systems. (5) In the fields of architectural environment and energy, diverse purposes of studies were conducted such as indoor environment, building energy, and renewable energy. In particular, renewable energy and building energy-related researches have mainly been studied as reflecting the global interests. In addition, various researches have been performed for reducing cooling load in a building using spot exhaust air, natural ventilation and energy efficiency systems.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.1
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• pp.167-175
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• 2019

To effectively deal with the fire in tunnel which is mostly the vehicle fire, it's more important to suppress the fire at early stage. In urban tunnel, however, accessibility to the scene of fire by the fire fighter is very limited due to severe traffic congestion which causes the difficulty with firefighting activity in timely manner and such a problem would be further worsened in underground road (double-deck tunnel) which has been increasingly extended and deepened. In preparation for the disaster in Korea, the range of life safety facilities for installation is defined based on category of the extension and fire protection referring to risk hazard index which is determined depending on tunnel length and conditions, and particularly to directly deal with the tunnel fire, fire extinguisher, indoor hydrant and sprinkler are designated as the mandatory facilities depending on category. But such fire extinguishing installations are found inappropriate functionally and technically and thus the measure to improve the system needs to be taken. Particularly in a double-deck tunnel which accommodates the traffic in both directions within a single tunnel of which section is divided by intermediate slab, the facility or the system which functions more rapidly and effectively is more than important. This study, thus, is intended to supplement the problems with existing tunnel life safety system (fire extinguishing) and develop the remote-controlled automatic fire extinguishing system which is optimized for a double-deck tunnel. Consequently, the system considering low floor height and extended length as well as indoor hydrant for a wide range of use have been developed together with the performance verification and the process for commercialization before applying to the tunnel is underway now.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2335-2347
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• 2023

As medical facilities are usually built at urban areas, special concrete aggregates and evaluation methods are needed to optimize the design of concrete walls by balancing density, thickness, material composition, cost, and other factors. Carbon treatment rooms require a high radiation shielding requirement, as the neutron yield from carbon therapy is much higher than the neutron yield of protons. In this case study, the maximum carbon energy is 430 MeV/u and the maximum current is 0.27 nA from a hybrid particle therapy system. Hospital or facility construction should consider this requirement to design a special heavy concrete. In this work, magnetite is adopted as the major aggregate. Density is determined mainly by the major aggregate content of magnetite, and a heavy concrete test block was constructed for structural tests. The compressive strength is 35.7 MPa. The density ranges from 3.65 g/cm³ to 4.14 g/cm³, and the iron mass content ranges from 53.78% to 60.38% from the 12 cored sample measurements. It was found that there is a linear relationship between density and iron content, and mixing impurities should be the major reason leading to the nonuniform element and density distribution. The effect of this nonuniformity on radiation shielding properties for a carbon treatment room is investigated by three groups of Monte Carlo simulations. Higher density dominates to reduce shielding thickness. However, a higher content of high-Z elements will weaken the shielding strength, especially at a lower dose rate threshold and vice versa. The weakened side effect of a high iron content on the shielding property is obvious at 2.5 µSv=h. Therefore, we should not blindly pursue high Z content in engineering. If the thickness is constrained to 2 m, then the density can be reduced to 3.3 g/cm³, which will save cost by reducing the magnetite composition with 50.44% iron content. If a higher density of 3.9 g/cm³ with 57.65% iron content is selected for construction, then the thickness of the wall can be reduced to 174.2 cm, which will save space for equipment installation.

• Journal of Korean Society of Transportation
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• v.26 no.3
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• pp.169-178
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• 2008

Level of Service (LOS) is one of ways to evaluate operational conditions. It is very important factor in evaluation especially for the facility of highways. However, some studies proved that ${\upsilon}/c$ ratio and accident rate is appeared like a second function which has a U-form. It means there is a gap between LOS and safety of highway facilities. Therefore, this study presents a method for evaluation of a signalized intersection which is considered both smooth traffic operation (delay) and traffic safety (accident). Firstly, as a result of our research, accident rates and EPDO are decreased when it has a big delay. In that reason, it is necessary to make a new Level of Service included traffic safety. Secondly, this study has developed a negative binominal regression model which is based on the relation between accident patterns and stream. Thirdly, standards of LOS are presented which is originated from calculation between annual delay costs and annual accident cost at each intersection. Lastly, worksheet form is presented as an expression to an estimation step of a signalized intersection with traffic accident prediction model and new LOS.

• Journal of the Korean Dietetic Association
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• v.10 no.3
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• pp.293-299
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• 2004

The purposes of this study were to : a) investigate the current status of contracted hospital food services, b) analyze and clarify various perspectives of contractors and hospitals. Thirty six hospitals and their contractors which were having more than 100 beds located in Seoul, Inchon and Kyungkido, were the subjects of this study. Data were collected through surveys. The survey was conducted during March to April in 2002. Questionnaires were mailed to the 36 directors of dietetic departments of hospitals and 36 managers of contract foodservice management company. Statistical analysis was completed using SPSS Win(11.0) for descriptive analysis, t-test and $x^2$-test. The results of the study can be summarized ; 1. The type of contract considered adequate by directors of dietetic departments and managers of contractors was fee-contract, combined type, followed by profit-and-loss contract. 2. According to the results from analysis on the contract cost per meal considered adequate by directors of dietetic departments and managers, the directors of dietetic department indicated that showing no difference with the current contract cost per meal. However, the managers of contractor indicated that showing significant differences compared with the current contract cost per meal(regular diet p<0.01, therapeutic diet p<0.001). 3. In the composition of contract cost per meal considered adequate, the managers of contracting businesses accounted labor cost (p<0.01) as a major cost, whereas the chiefs of nutrition departments accounted miscellaneous or controllable expense (p<0.001) and VAT (p<0.01) as major costs. 4. The directors of dietetic departments and managers thought that the hospital should be responsible for utility costs. On the other hand, directors of dietetic departments regarded that the contractor and managers thought that the hospital should pay for facility investment cost.

• Journal of radiological science and technology
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• v.31 no.4
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• pp.347-353
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• 2008

This study is to prepare an evaluation standard about personal information protection and security management of a medical institution and to build up a grade standard of evaluation in PACS environment. We built up evaluation index based on 10 detailed items in four big categories (political security, technical security, data management security and physical security) by referring to ISO17799 (BS 7799), HIPPA (Health Insurance and Portability and Accountability Act of 1996) and domestic medical law. We have investigated at the thirty places where medical facility with the extracted security criteria and security evaluation index. Average score of physical security list, one of the big categories, was 18.5/20 (93%) at all medical institutions. Political security score was 18.5/30 (62%), data management security score was 12/20 (60%) and technical security score was 17.5/30 (58%). Therefore, security evaluation score was average 67 in 30 general hospitals, which was 4th level. The results showed that it is necessary to establish evaluation and management standard about personal information protection and security consciousness which are weak in PACS environment.

• The Journal of Korean Academic Society of Nursing Education
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• v.4 no.2
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• pp.204-219
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• 1998

The use of instructional media in nursing education was investigated using a descriptive research methodology. Data were collected from 199 professors teaching in the areas of Fundamental Nursing (48 subjects), Adult Nursing(56 subjects), Pediatric Nursing(49 subjects), and Community Health Nursing(46 subjects). 120 professors were from 3-year college of nursing and 79 professors were from 4-year college of nursing, Data were analyzed using descriptive statistics (mean, standard deviation), and ANOVA with SPSS $PC^+$ program. The results are as follows. 1) The general attitude of the subjects toward the use of instructional media was positive(mean : 3.75). However, from the ANOVA result the subjects from 4-year college of nursing had more positive attitudes in the areas of media utilization and supply system. Most subjects had high interest in the areas of effectiveness of the media, and media literacy in using instructional media. 2) OHP(mean was 3.76) and VTR(mean was 3.36) were the most used instructional media in nursing education. These media were efficiently supplied by the school. However, other media like CD-ROM, Opaque Projector, and LCD or beam Projector were not sufficiently provided by the school. 3) The main reasons to use instructional media were that the use of media is effective to raise students' attention and learning motivation. 4) Insufficiency of the media and environment to use media were the causes of the lack of using instructional media. 5) The use of PC communication of internet, LCD or beam Projector, and Computer Graphics was low. The reasons were that the subjects did not have enough knowledge and skills to use these media, and there was lack of media or environment. 6) In general, environment to use media of the 3-year college of nursing was worse than that of 4-year college of nursing. However, there was no significant differences between the two groups in the use of media related to their position, and subject. On the basis of the study results professors teaching nursing have positive attitudes to use instructional media but the lack of media supply or facility to use media limited the use of instructional media.

• Asian Journal of Turfgrass Science
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• v.22 no.1
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• pp.1-12
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• 2008

Remote sensing using multispectral radiometry may be a useful tool to detect drought stress in turf. The objective of this research was to investigate the correlation between drought stress and multispectral reflectance (MSR) from the turf canopy. St. Augustinegrass (Stenotaphrum secundatum[Walt.] Kuntze.) cultivars 'Floratam' and 'Palmetto', 'SeaIsle 1' seashore paspalum Paspalum vaginatum Swartz.), 'Empire' zoysiagrass (Zoysia japonica Steud.), and 'Pensacola' bahiagrass (Paspalum notatumFlugge) were established in lysimeters in the University of Florida Envirotron greenhouse facility in Gainesville. Irrigation was applied at 100%, 80%, 60%, or 40% of evapotranspiration (ET). Weekly evaluations included: a) shoot quality, leaf rolling, leaf firing b) soil moisture, chlorophyll content index; c) photosynthesis and d) multispectral reflectance. All the measurements were correlated with MSR data. Drought stress affected the infrared spectral region more than the visible spectral region. Reflectance sensitivity to water content of leaves was higher in the infrared spectral region than in the visible spectral region. Grasses irrigated at 100% and 80% of ET had no differences in normalized difference vegetation indices (NDVI), leaf area index (LAI), and stress indices. Grasses irrigated at 60% and 40% of ET had differences in NDVI, LAI, and stress indices. All measured wavelengths except 710nm were highly correlated (P < 0.0001) with turf visual quality, leaf firing, leaf rolling, soil moisture, chlorophyll content index, and photosynthesis. MSR could detect drought stress from the turf canopy.

• Management & Information Systems Review
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• v.30 no.2
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• pp.57-79
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• 2011

One of the fastest growing sector in tourism industry is MICE industry due to globalization among the countries in various parts including business, politics, and cultural exchange. The objectives of this research can be in two fold: firstly, to evaluate the convention service quality and categorize them into three groups, basic service, performance service and exciting service; secondly, to provide the exciting service as a recovery program to restore customer satisfaction and their intention to reuse when the basic or performance service failure occurs. The results are as follows: among the four dimensions of the service quality, only the availability of information and the employee's performance were effected by the exciting service quality. Secondly, employees's performance can only be effected by the exciting service when customer service factor is included prior to the events. Thirdly, the following dimensions of services were not selected to be effective by the exciting services: conditions of physical facility, related infra-structure, the process of customer service and the program. Fourthly, only the additional services and events were selected to be the effective exciting services for the recovery program.

• Journal of the Korean Geographical Society
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• v.47 no.4
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• pp.606-624
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• 2012

The main objective of this paper is to provide an adequate and comprehensive review of what has been done in South Korea in the field of geospatial analysis and modeling. This review focuses on spatial data analysis and spatial statistics, spatial optimization, and geosimulation among various aspects of the field. It is recognized that geospatial analysis and modeling in South Korea got through the initial stage during the 1990s when computer and analytical cartography and GIS were introduced, moved to the growth stage during the first decade of the $21^{st}$ century when there was a surge of relevant researches, and now is heading for its maturity stage. In spatial data analysis and spatial statistics, various topics have been addressed for spatial point pattern data, areal data, geostatistical data, and spatial interaction data. In spatial optimization, modeling and applications related to facility location problems, districting problems, and routing problems have been mostly researched. Finally, in geosimulation, while most of research has focused on cellular automata, studies on agent-based model and simulation are in beginning stage. Among all these works, some have fostered methodological advances beyond simple applications of the standard techniques.