• Journal of Navigation and Port Research
• /
• v.35 no.8
• /
• pp.631-636
• /
• 2011

Stable power supply to a light mounted on a navigational buoy is indispensable factor because unstable power can lead to fatal marine accident. Despite the difference lies between onshore and offshore environment, as well as the power output characteristics, the PV(Photovoltaic) power generation system is designed by the independent onshore power generation system standards. Furthermore, the capacity of PV power generation system does not take into account the structural characteristics of the buoy in the sea. Therefore, the faulty design makes battery over-discharge owing to lack of the power generation and the battery can not supply stable power to the light. This paper introduces a design method for a power system of the PV powered buoy. The data has been acquired for 3 months period, which includes PV-generated electricity, power consumption and battery voltage from experimental buoy. Further, a power management features of the buoy has been analyzed based on the acquired data. From the analysis of the acquired data, it was evident that PV power generation system produces different electric power output depend on its installed environment - land and sea. Based on the analytical result, a design criterion has been proposed for the power system in the navigational buoy.

• Korean Journal of Construction Engineering and Management
• /
• v.12 no.4
• /
• pp.29-39
• /
• 2011

In Korea, many mixed-used development projects(MXD) in mega project size are currently active. As these mega projects require long-term construction and execution and involve by different subjects in different fields, their completion breeds various problems, such as conflicts among project participants due to their complicated interest relationships and inaccuracy in predicting the economic performance of the projects due to inappropriate facility capacity planning. To solve these problems, it is essential to apply value engineering (VE) at the planning phase of the project, which can result in the best possible cost reduction and improvement of project performance. However, not many projects are actually implementing VE because of the lack of available information, as well as the limitations due to uncertainty in the early period of project execution. Therefore, this study aimed at proposing VE Team Building, Quality Model Performance Indexes, Space Model so as to resolve common mega project problems and overcome VE application limitations at planning stage. The result of this study is expected that the data can be utilized as basic data to apply VE at the planning phase of the large complex projects.

• Journal of Environmental Impact Assessment
• /
• v.25 no.1
• /
• pp.15-24
• /
• 2016

This study was analyzed the distribution tendencies and statuses of development projects for EIA projects. According to the result of this study, in the annual analysis, a number of consultations and areas have shown increasing trend across the board. In the project type analysis, there are development project types; urban development, industrial complex, sport facility installation, resort complex development, road construction, which have a lot of developments. In the cities analysis, a number of consultations were about 53% on the top 5 cities, the areas were focused on 75%, and the development projects were concentrated in the southern distribution of Gyeong-gi province. The development axis, from 2004 to 2006, was C-type, but it was extended to O-type until 2010. Therefore, the development will expand into nature conservation zones and forest areas to the east. The development restriction area will be disappeared gradually because the development density of the surrounding Seoul city is more advanced, and we could predict that may be accelerated conurbation between the neighboring cities. Thus, when the development project is located, it would be reviewed difference in existing development project type, project size, and concentration in each city on the basis of environmental capacity.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.1 no.1
• /
• pp.65-72
• /
• 2003

Adsorption and desorption characteristics of methyl iodide at high temperature conditions up to 25$0^{\circ}C$ by TEDA-impregnated activated carbon and silver-ion exchanged zeolite(AgX-10), which are used for radioiodine retention in nuclear facility, were experimentally evaluated. In the range of temperature from 3$0^{\circ}C$ to 25$0^{\circ}C$, the adsorption capacity of base activated carbon decreased sharply with increasing temperature but that of TEDA-impregnated activated carbon showed higher value even at high temperature ranges. Especially, the residual amount of methyl iodide after desorption on TEDA-AC represented 30% lower value than that on AgX-10. However, it can be used as an adsorbent for the removal of methyl iodide up to 15$0^{\circ}C$ if it is preventing explosion by Ignition. The breakthrough curves of methyl iodide in the fixed bed packed with AgX-10 uP to 40$0^{\circ}C$ were compared upon the effects of bed temperatures, bed depth and input concentration of methyl iodide. Removal mechanism of methyl iodide on AgX-10 was proposed, based on the analysis of by-product gas generated from adsorption reaction.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.24 no.1
• /
• pp.44-52
• /
• 1982

Recently, estuary reserovoirs have been actively constructed in Korea and also in Japan there are a large number of estuary reservoirs constructed. But most of the estuary reservoirs are located at the downstream of a river where geographical condition is best for the construction of an enclosing dam. And an effective utilization of water from the estuary reservoir seems to be difficult even if estuary reservoirs are considered to be the water resources the most available for their watershed. Studies on estuary reservoirs so far have been mainly concentrated on the physical and engineering problems of the dam construction itself. The purpose of the present study is to review the estuary reservoir planning in connection with the water resources development and to study a basis of the planning. First, the levels of water use in Korea and Japan were compared with those of other countries in the world. And then, some representative reservoirs were selected to study the roles of a reservoir and water-using conditions in the watershed. Based on the study, a survey was given on the relation between a dam construction upstream and an estuary reservoir construction downstream of a river. Finally, a comprehensive examination was made of the bases of estuary reservoir planning. (1) The estuary reservoir planning is deeply related to the plan for water use develo- pment in the watershed. After the upstream water resources were fully developed up to the most, water reso- urces development by an estuary reservoir should be started. (2) If an estuary lake has a capacity big enough, it can store flood discharge of the watershed without any loss and become a basic facility that will bring about the maxi- mum use of water from the watershed. (3) Estuary reservoirs store water used in the upstream watershed, so recycling of water use is attained by the reservoir. Water in the estuary lake is difficult to be fresh water in its long run. Therefore, estuary reservoir should be located at a place where polluted water is purified and refused. All the planning should be based on the assumption that water in the estuary lake is not fresh but polluted after a long time. (4) The estuary lake can only supply water to the lower basin directly. But the upstream area is benefited from the estuary lake by exchange of irrigation water sources between the lower and the upper area. So a large-scale exchange plan between new and existing water resources is important. By constructing estuary reservoirs and the exchange of water sources between upper and lower areas, the reasonable maximum use of water from the whole watershed is at- tained. (5) The big problem coming from the water resources development by an enclosing estuary is salt water intrusion into the lake. To maintain the estuary lake salt-free, multi-purpose use of the lake should be avoided. It is necessary to take such fundamental measures as abolition of back flow operation of gate, and the closing of the fish port and the fish ladder. The results mentioned above were found in this study and these results of this study could be used for the adequate planning of estuary reservoirs in connection with the maximum water use of the watershed.

• Journal of the Korean Dietetic Association
• /
• v.12 no.4
• /
• pp.313-328
• /
• 2006

This study was objectively performed to identify dietitians' job in the elderly health-care facilities, to assess facilities and dietitian's demographic characteristics, and to determine performance and importance of dietitian's job including the demand of therapeutic diet development. Survey was conducted by mail and samples were the dietitians working in 376 facilities which capacity is over 50 members from nationwide 583 the elderly health-care facilities. Returned questionnaire was 102 and used for statistic analysis. The distributions of the elderly health-care facilities showed 39 the elderly nursing facilities(38.2%), 32 skilled nursing facilities (32.4%), 13 geriatrics hospital facilities(12.7%) and 9 the elderly cost nursing facilities(8.8%). 60.0 percent of the samples showed its menu price as 1,000 to 1,500 won. A cycle-menu program was in-use at the 79.0% facilities, but only 7.1% facilities have been introduced a selected menu system. 92.9% facilities employed only one dietitian. In the demographic characteristics of dietitian only 14.7% dietitian had a clinical dietitian license and 51.5% of respondents answered at least 1 to 3 months internship program is needed. Job activities of the dietitian in the elderly health-care foodservice were identified as 45 activities with 9 dimensions. Job performance score evaluated dietitian oneself was 4.71 of 7 points. The average importance score that the dietitian evaluated their own job was 5.66 points of 7. The job activities shown higher importance but lower performance were therapeutic diet development for in-patients, menu development suitable for taste of the elderly, and leadership. Job performance score by characteristics of dietitian and their elderly health-care facilities was significantly associated with experience of dietitian in elderly health-care (F=4.480, p<0.05), education of dietitian(F=2.659, p<0.01), number of dietitian(F=2.245, p<0.05), and number of employee in foodservice(F=2.607, p<0.05). Most common diseases of the aged was proved as hypertension(81.7%), diabetes mellitus(71.4%), and dementia(65.0%). The therapeutic diets frequently provided were diabetes mellitus diet, dysphagia diet, low sodium diet, high fiber diet, and high protein diet, in order. For those reasons, dietitian in the elderly health care emphasized that the information about therapeutic diet development such as diabetes mellitus diet, dysphagia diet, low sodium diet and hypertension diet must be continuously developed and provided. The result from this study can be applicable to enlarge and enrich job activities of dietitian in elderly health-care foodservice.

• Nuclear Engineering and Technology
• /
• v.46 no.4
• /
• pp.547-556
• /
• 2014

Korea expects a shortage in storage capacity for spent fuels at reactor sites. Therefore, a need for more metal and/or concrete casks for storage systems is anticipated for either the reactor site or away from the reactor for interim storage. For the purpose of interim storage and transportation, a dual purpose metal cask that can load 21 spent fuel assemblies is being developed by Korea Radioactive Waste Management Corporation (KRMC) in Korea. At first the gamma and neutron flux for the design basis fuel were determined assuming in-core environment (the temperature, pressure, etc. of the moderator, boron, cladding, $UO_2$ pellets) in which the design basis fuel is loaded, as input data. The evaluation simulated burnup up to 45,000 MWD/MTU and decay during ten years of cooling using the SAS2H/OGIGEN-S module of the SCALE5.1 system. The results from the source term evaluation were used as input data for the final shielding evaluation utilizing the MCNP Code, which yielded the effective dose rate. The design of the cask is based on the safety requirements for normal storage conditions under 10 CFR Part 72. A radiation shielding analysis of the metal storage cask optimized for loading 21 design basis fuels was performed for two cases; one for a single cask and the other for a $2{\times}10$ cask array. For the single cask, dose rates at the external surface of the metal cask, 1m and 2m away from the cask surface, were evaluated. For the $2{\times}10$ cask array, dose rates at the center point of the array and at the center of the casks' height were evaluated. The results of the shielding analysis for the single cask show that dose rates were considerably higher at the lower side (from the bottom of the cask to the bottom of the neutron shielding) of the cask, at over 2mSv/hr at the external surface of the cask. However, this is not considered to be a significant issue since additional shielding will be installed at the storage facility. The shielding analysis results for the $2{\times}10$ cask array showed exponential decrease with distance off the sources. The controlled area boundary was calculated to be approximately 280m from the array, with a dose rate of 25mrem/yr. Actual dose rates within the controlled area boundary will be lower than 25mrem/yr, due to the decay of radioactivity of spent fuel in storage.

• Journal of Korean Port Research
• /
• v.13 no.2
• /
• pp.333-350
• /
• 1999

Today freeway is thought to be a very important transportation facility carrying tremendous traffic flow as the main corridor within the area of between the areas. However freeway is experiencing severe congestion and accidents by increased entrance ramp flow especially at peak time period. Ramp meters on the freeway entrance ramps that supply traffic to the freeway in a measured or appropriately regulated amount are needed for alleviating freeway congestion. Because ramp meters can be operated to discharge traffic at a measured or regulated rate thus maintaining more uniform speed on the mainline section maximizing the throughput to the freeway within the capacity of a downstream bottleneck and reducing the congestion related accidents. Thus the objectives in this study were to analyze the traffic characteristics on the freeway I-94 with ramp metering system before/after ITS technology in Detroit (Michigan) area compare shifts of the traffic characteristics on the freeway I-94 before/after ITS technology and finally suggest a better ramp metering strategy for the freeway system The following results were obtained: i)Flow occupancies and speeds on the mainline merge section of freeway were shown to be a big difference depending on the peak periods areas and directions based on the distribution of traffic flow characteristics on the freeway. ii)Reduced speed was shown to be more than 5 mph and ramp flow was also shown to be more than 240 vph at peak periods if there was the ramp metering system constructed on the freeway. iii)Ramp metering system was shown to be optimally operated on the freeway if ramp flow could be maximized within the range of over 900 vph and reduced occupancy could be also maximized by no more than 2 percent at peak periods. iv)The average flows on the freeway after the ITS technology were shown to be a decrease of over 20% depending on the peak periods areas and directions when compared with those flow on the freeway before the ITS technology. over 20% depending on the peak periods areas and directions when compared with those speeds on the freeway before the ITS technology. vi)The average metering rates on the freeway after the ITS technology were shown to be an increase of over 10% depending on the peak periods areas and directions when compared with those metering rates on the freeway before the ITS technology.

• Clean Technology
• /
• v.13 no.2
• /
• pp.151-158
• /
• 2007

An experimental study to investigate the condensing heat transfer characteristics of small diameter horizontal double pipe heat exchangers with R-22 and R-410A was performed. Experimental facility was constructed to calculate and observe HTC(heat transfer coefficients), flow patterns and pressure drop. The main components include a liquid pump, an evaporator, a condenser(test section), a sight-glass, pressure taps and measurement apparatus. Two pipes of different diameters are tested; One 5.35 mm ID 0.5 mm thick, the other 3.36 mm ID 0.7 mm thick. The mass flow rate ranged from 200 to $500\;ks/m^2{\cdot}s$ and heating capacity were form 1.0 to 2.4 kW. The flow patterns of R-22 and R-410A were observed with a high speed camera through the sight-glass. The tests revealed that HTC of R-410A was higher than that of R-22 by maximum 5%. Annular pattern was observed for the most cases but stratified flow was also detected when x<0.2. The pressure drop in 3.36 mm ID pipe was higher than that of 5.35 mm by $30{\sim}50%$. Comparing with previous correlations such as Shah, Fujii and Soliman's, Fujii' showed the best good agreement with my data with a maximum deviation of 40%.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.6
• /
• pp.201-209
• /
• 2012

This study was conducted in order to empirically analyze factors affecting the quality of life in the elder resulting from the use of elderly leisure facilities in the community. For this purpose, we surveyed the elder using the senior health town of Gwang-ju Metropolitan City to see whether the quality of life in the elder is influenced by factors such as facilities' environment within the health town, the capacity for the staff and instructors, and the elders' satisfaction with programs. The results of this study are expected to provide practical solutions for enhancing the quality of life in senior users. The survey was performed with 1,038 elders aged over 60 who were using the senior health town of Gwang-ju Metropolitan City by using a self-administered questionnaire and being interviewed with surveyors. The period of the survey was from the 10th to 15th of December, 2010. According to the results of this study, variables affecting the elders' quality of life were academic qualification (B= .074, p<0.05), instructors satisfaction (B=.172, p<0.001), staff satisfaction (B=.104, p<0.01), and facilities and environment satisfaction (B=.217, p<0.001). That is, the lower academic background they have, the higher instructors', staff's, facilities and environment's satisfaction are, the quality of life in the elder was positively affected. In particular, facilities and environment's satisfaction show a relatively high effect and this suggests the necessity to modernize cultural and leisurely facilities in community for senior citizens and create pleasant environment in order to improve the quality of life in the elder.