• 한국안전학회지
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• 제11권1호
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• pp.75-83
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• 1996

This paper was concerned with pool fire about many used kerosene and diesel oil. In order to know the thermal effects of kerosene and diesel oil, temperature change in the pool fire of these fuels were obtained as a variation of combustion time and the tank's height and diameter by using the data acquisition system, And fuel combustion velocity were derived as a function of the diameter and wall thickness of tanks and combustion time. As a result, when the tank's height was 15㎝, the greater diameter the higher temperature rising regardless of tank's wall thickness and fuels. But, when the tank's height is 30㎝, temperature rising was not higher than 15㎝. Also, temperature rising in the pool fire of kerosene much higher than diesel oil. Kerosene's combustion velocity was about two times faster than diesel oil. And, kerosene's combustion velocity was increased according to the increasing of tank's diameter and combustion time. But, diesel oil's combustion velocity was a little increased or not. Surrounding temperature change of tank with the pool fire was obtained temperature distribution of 0∼35℃ according to the change of tank's diameter and distance from the tank's wall.

• International Journal of Air-Conditioning and Refrigeration
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• 제17권3호
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• pp.81-87
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• 2009

The effect of oil on convective boiling of R-123 in an enhanced tube bundle is experimentally investigated at $26.7^{\circ}C$ saturation temperature. The enhanced tube had pores (0.23 mm diameter) and connecting gaps (0.07 mm width), which had been optimized using pure R-123. The effects of oil concentration (0 to 5%), heat flux (10 to $40\;kW/m^2$), mass velocity (8 to $26\;kg/m2^s$) and vapor quality are investigated. The oil significantly reduces the bundle boiling heat transfer coefficient. With 1% oil, the reduction is approximately 35%. Further addition of oil further reduces the heat transfer coefficient. The data are also compared with the pool boiling counterpart. The reduction in the heat transfer coefficient is smaller in a bundle (convective boiling) than in a pool (single-tube pool boiling), with larger difference at a smaller heat flux. Similar to pure R-123 case, the effects of mass velocity and vapor quality are negligible for the convective boiling of R-123/oil mixture.

• 설비공학논문집
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• 제18권3호
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• pp.254-261
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• 2006

The effect of enhanced geometry (pore diameter, gap width) is investigated on the pool boiling of R-123/oil mixture for the enhanced tubes having pores with connecting gaps. Tubes with different pore diameters (and corresponding gap widths) are specially made. Significant heat transfer degradation by oil is observed for the present enhanced tubes. At 5% oil concentration, the degradation is 26 to 49% for $T_{sat}=4.4^{\circ}C$. The degradation increases 50 to 67% for $T_{sat}=26.7^{\circ}C$. The heat transfer degradation is significant even with small amount of oil (20 to 38% degradation at 1% oil concentration for $T_{sat}=4.4^{\circ}C$), probably due to the accumulation of oil in sub-tunnels. The pore size (or gap width) has a significant effect on the heat transfer degradation. The maximum degradation is observed for $d_p$ = 0.20 mm tube at $T_{sat}=4.4^{\circ}C$, and for $d_p$=0.23 mm tube at $T_{sat}=26.7^{\circ}C$. The minimum degradation is observed for $d_p$=0.27 mm tube for both saturation temperatures. It appears that the oil removal is facilitated for the larger pore diameter (along with larger gap) tube. The highest heat transfer coefficient with oil is obtained for $d_p$ =0.23 mm tube, which yielded the highest heat transfer coefficient for pure R-123. The heat transfer degradation increases as the heat flux decreases.

• 설비공학논문집
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• 제22권10호
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• pp.704-709
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• 2010

The effect of oil on flow boiling of R-123 in a plain tube bundles was experimentally investigated for a range of quality and heat flux. It is shown that the heat transfer coefficient decreased as the oil concentration increased. Comparison with the previous pool boiling data reveals that the reduction of heat transfer coefficient by oil is more pronounced in pool boiling, and the difference increased with the increase of oil concentration and heat flux. Within the experimental range, the variation of mass flux or quality has negligible effect on the heat transfer coefficient.

• 대한안전경영과학회지
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• 제13권2호
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• pp.157-167
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• 2011

Currently, interest on physical distribution is increasing due to burden of oil cost increases as oil price rises day by day. As interest grows, there are number of studies have been conducting on saving the cost of distribution. On the other hand, number of study on service of distribution is insufficient. Actually, subject of service of physical distribution have been studied by number of survey organizations, research organizations and mass media. Although, configuration for each organization is different from each other and it is hard to measure objective satisfactory factor of customers. This means needs for constructing standardized measuring tool as well as research on measuring service quality of distribution is not active. Therefore, this research is to compare and analyze compatibility of service quality measuring using SERVQUAL and SERVPERF and trying to clarify differences affected by importance service quality by each level to actual service quality. Also, this research is to make basic and standardized measuring model to improve quality of physical distribution especially using analysis of service quality and customer satisfaction of pallet pool service which contributes rationalization of distribution and reduce the cost by standardizing specification and size of pallet, allowing sharing of pallet. To conduct this research, case study of a company A is used where it is in a pallet pool business. Using this example, the goal is to give help on pallet pool business a strategic exercise if the business by point out major factors that affect customer satisfaction by collecting customer assessment along with examination of SERVQUAL and SERVPERF in measuring service quality if pallet pool service.

• 대한설비공학회지:설비저널
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• 제12권4호
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• pp.240-251
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• 1983

The municipal government of Daejeon, Korea set up a plan to retrofit solar energy to the existing swimming pool. The pool was constructed in 1980, and meets the requirements of International standard. It will be used for the 1986 Asian Games and the 1988 Seoul Olymipics. The roof structure of the existing pool is to be modified to accomodate trickle solar collectors. In addition, various energy conserving ideas will be applied to the existing building structure. For the prevention of over heating of collectors on the roof, natural air convection scheme will be adopted within the collector system. Natural convection of passive type heating would be also adopted for the space heating of the pool when the system is idle. At present, the pool can be utilized only for two months a year without auxilairy heating. With oil heating, the energy cost would be too high for the normal operation. When this project completed in March 1984, it would be expected to be openable for seven months a year without a significan amount of auxiliary heating. In this project, two dimensional numerical analysis technic have been used to analyse the characterisitics of thermal performance of the swimming pool system. An experimental tat verification of the theoretical analysis have been also attempted.

• 연구논문집
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• 통권24호
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• pp.41-48
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• 1994

This experimental study deals with the extinguishiment characteristics of an oil pool flame using the water spray. The water through the six different atomizers is ejected over the freely burning pool flame in the quiescent surrounding air. Injection direction is vertical to the surface of oil in a small tank with a diameter of 100mm and a height of 10mm. In order to estimate quantitatively the extinction, the burning rate as well as the effective water flux are measured. The effective water flux is the amount of the water which reach the pool from the nozzle. The burning rate with the water spray increases until the injection pressure increases to reach some value, which gives the maximum burning rate, while the effective water flux without the flame decreases or does not change according to increasing of the injection pressure. This maximum burning rate is greater than 2.5 times of burning rate of the fire without the water spray. As a matter of the extinguishiment, it is found that the water drops of which size is too small can not extinguish the fire because too small drops does not reach the fuel surface.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.121-127
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• 2012

Whine noise in engine oil pump system was issued in developing an engine. Generally, A noise of engine oil pump largely are classified two cases. The first one is a gearing noise caused by relative motion of inner rotor and outer rotor. The other is fluid pulsation noise caused by oil pressure fluctuation. The aim of the paper is to identify a noise mechanism in engine oil pump and improve its Noise. Also, it suggests to the guide line on the design of oil pump.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.479-482
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• 2003

In this study, the solubilization of dense nonaqueous phase liquid (DNAPL) using oil-based emulsion was investigated for aquifer remediation. The micro-sized oil emulsion has large surface areas and buoyancy force, therefore it can be effective in treating DNAPL pool of the aquifer without downward migration of DNAPLs. The emulsion was prepared using silicone oil and mechanical homogenization. And the prepared emulsion had micro-sized similar distribution: 99 % in number and 80 % in volume were less than 10${\mu}{\textrm}{m}$. As target pollutants, trichloroethylene and 1, 2 dichlorobenzene were selected. All of used DNAPLs were solubilized successfully in oil-based emulsion. Even at low oil percentage, emulsion showed good solubility against pollutants. Therefore, the remediation using oil-based emulsion was considered as an effective alternative in dealing with DNAPLs of the aquifer.

• 동굴
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• 제85호
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• pp.28-34
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• 2008

For trying to frontal attack of new solution by fusion of technical tasks and conditions with it's solving methods of the essential tasks of marine resource development and environmental conservation in addition with elements of electronic high-technologies, the magnetic oil spill adsorbent of Mag-Sorbent* has been prepared and proposed to dispose oil spill from the marine disaster for preventing oil pollution by using them and their system with sequentially circular collection of oil spill mag-sorbent powder and fabrics on the electronic equipment like as barge robot for the scheme of sustainable development of environment-friendly technology. Because of recent marine accident occurred at Tae-An cost and earthquake in Sichuan province were very large scale accident of disaster to prevent and manage of them. So, it was verified from the experiment of electronic demonstrator that the skimmer system of oil spill mag-sorbent powder and fabrics prepared was very effective and useful technique to collect oil spill samples on the water surface specially at the closed space of underground cave. At this point, the barge-based electronic remote control was very useful system operating easily on the marine fields but also water level at the small pool to skim it with the environment-friendly system of the disposing marine disaster and preventing oil pollution using magnetic adsorbents of Mag-Sorbent*.