• Journal of Acupuncture Research
• /
• v.24 no.1
• /
• pp.49-77
• /
• 2007

Objectives: The purpose of this study is to investigate the mechanism and effect of moxa bucket moxibustion. Objectively, to be used as the quantitative data through the measurement of temperature, and to grasp the thermodynamic characteristics of moxa bucket moxibustion. Methods: We have selected of the moxa bucket moxibustion. We make a comparative study of the thermodynamic characteristics of moxa bucket moxibustion. We examined combustion times, temperatures, temperature gradients in each period during a combustion of moxa bucket moxibustion made by oak wood. Results: 1. We can design the moxa bucket moxibustion that it has 57.6$^{\circ}C$ maximum temperature with 7g weight and 10mm height, if we use more weight of moxa or lower the height of moxa, we can observe relatively elavated maximum temperature. We observe the maximum temperature following the measuring position of moxa bucket and we can see higher temperature at the center of the moxa bucket and lower temperature at the side of the moxa bucket. 2. We can design the moxa bucket moxibustion with 5g moxa and 10mm height that it has 0.121 $^{\circ}C$/sec of maximum temperature gradient, and it has relatively high temperature gradient at lower weight and height condition. 3. We can design the moxa bucket moxibustion with 7g moxa and 15mm height that it has 4,135sec of the longest effective temperature combustion time, if we use more weight of moxa or higher height of moxa, we can observe relatively extended effective temperature combustion time. We observe the longest effective combustion time following the measuring position of moxa bucket. We can see higher temperature at the center of the moxa bucket and lower temperature at the side of the moxa bucket.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.12
• /
• pp.167-174
• /
• 2011

This paper described the estimation methods of CO2 emission of vehicles. The important of energy and environment has emerged in the world, and the field of vehicle's development as well. CO2 was particularly the object of emission-regulation that caused of global warming. There are performance comparison methods by driving mileage, International Panel on Climate Change (IPCC) and chemical equation for the combustion of Octane. We took the measurement by getting data through OBD-II port from vehicle covered 5 km on road. We got the diagnosis information, specific mileage and fuel consumption in this experiment. We are able to expect similar CO2 emission by the methods in the normal speed driving. Also, we can make more realistic approach of CO2 emission by the method of estimation by IPCC and chemical equation for the combustion of Octane in rapid acceleration driving.

• Fire Science and Engineering
• /
• v.30 no.3
• /
• pp.48-54
• /
• 2016

Pilotis are support columns that lift a building above the ground. Thus, they can elevate the lowest floor to the secondfloor level and, in Korea, are used to leav a parking area below multifamily housing. However, if there is a fire in the piloti area, the cars and main entrance door are wrapped in flames. Due to the inflammability of the materials, the combustion of the cars and insulation at the ceiling of the pilotis, having a high heat release rate, can quickly destroy the front entrance of the building and spread heat, flames and a poisonous gas to the stairs and elevator pit. Therefore, the fire can quickly spread to the whole building, putting the lives of the residents in danger. This study was an in-depth accidental case study of the "Uijeongbu Fire Accident" that killed 5 residents and injured 139 others. The study identified the relationships between the fire at the piloti structure of multifamily housing and the vulnerability of this structure and its inherent weaknesses.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.30 no.1
• /
• pp.114-123
• /
• 2002

A supersonic rocket plum flowfield of kerosene/liquid-oxygen based propulsion system has been analysed using the Reynolds-averaged Navier-Stokes equations coupled with a 9-species 14-reaction finite-chemistry model. The result were compared with chemically frozen flow solution to investigate the effect of finite-rate chemistry on the plume flowfield. The computations were performed using a commercial CFD software, FLUENT 5. The finite-rate chemistry solution exhibited higher temperature caused by the reactions within the nozzle. All the chemical reactions within the plum were dominated only in the shear layer and behind the barrel shock reflection region where the temperatures are high and the effect of finite-rate chemical reactions on the flowfield was found to be insignificant. However, the present plume computation including the finite-rate chemical reaction within the plume has revealed major reactions occurring in the plum and their reaction mechanisms.

• Journal of the Korean Society of Industry Convergence
• /
• v.17 no.4
• /
• pp.234-244
• /
• 2014

Recently it has been focused that the automobile engine has developed in a strong upward tendency for the use of the high viscosity and poorer quality fuels in achieving the high performance, fuel economy, and emission reduction. Therefore it is not easy to solve the problems between low specific fuel consumption and exhaust emission control at motor cars. In this study, it is designed and used the engine test bed which is installed with turbocharger and intercooler. In addition to equipped using CRDI by controlling injection timing with mapping modulator, it has been tested and analyzed the engine performance, combustion characteristics, and exhaust emission as operating parameters, and they were engine speeds(rpm), injection timing(bTDC), and engine load(%). From the result of an experimental analysis, peak cylinder pressure and the rate of pressure rise were increased, and the location of it was closer toward top dead center according to the increasing of engine speed and load, and with advancing injection timing. The combustion characteristics are effected by fuel injection timing due to be enhanced the mass burned fraction. Using the engine dynamometer for analyzing the engine performance, the engine torque and power have been enhanced according to advancing the fuel injection timing. In analyzing of exhaust emission, there has been a trade-off between PM and NOx with increasing of engine speed and load, and with advanced injection timing. The experimental data are shown that the formation of NOx has increased and PM, vice versa.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.4 no.2
• /
• pp.61-65
• /
• 1971

It is well known that shellfish absorb and accumulate heavy metals in the water environment. When the concentration of the heavy metals in the water is above guideline, we find abnormal accumulation of them in the body of shellfish. This study on green oysters is an instance showing the relationship between the abnormal accumulation of heavy metal and industrial wastewaters containing it. The influence of the industrial wastewaters upon shellfish has been discussed from the statistical, physiological, and saprobiensystematic points of view, and the author wants to make clear of the absorption and accumulation mechanism of the heavy metals and physiological situation. This paper deals with the copper-contents in the meat of oysters which were collected in Changhang Bay and Daechun area, the latter being not supposed to be influenced by the water of the Kum River during the period from October 1970 to february 1971. The mean value of the copper contents in oysters caught at the sampling station in the Changhang Bay area is ranged from 851.5 to 143.1mg Cu/kg wet base, and that of Daechun area varied from 13.0 to 27.4mg Cu/kg wet base, so an evident difference is seen at a significance of $0.1\%$. It appears that one of the environmental factors making copper concentrated in the oysters of the Changhang area is due to the copper-contaning slug being discharged into the sea water by the Changhang Ore Refinery.

• Journal of Radiation Protection and Research
• /
• v.38 no.4
• /
• pp.189-193
• /
• 2013

Annual dose on the containment building wall of the interim storage facility at normal condition was calculated to estimate the dose rate transition of the facility of PWR spent nuclear fuel. In this study, source term was generated by ORIGEN-ARP with 4.5 wt% initial enrichment, 45,000 MWd/MTU burnup and 10 years cooling time. Modeling of the storage facility and the containment building and radiation shielding evaluations were conducted by MCNP code depending on the distance between the wall and the facility in the building. In the case of the centralized storage system, the distance required for the annual dose rate limit from 10CFR72 was estimated to be 50 m.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.22 no.3
• /
• pp.81-89
• /
• 2018

In this study, the operating characteristics of a small-scale pulse detonation engine (PDE) were investigated experimentally for application as a small thruster and an igniter. The PDE was constructed using commercial gas tubes with an inner diameter of 4.22 mm. The operating and detonation propagation characteristics of the PDE were investigated over the ranges of equivalence ratios and operating frequencies. Measured detonation speed was close to 10% of the theoretical CJ values at 1 Hz and 5 Hz conditions. However, unstable propagation characteristics were shown at 20 Hz and lean conditions, where the velocity deficit was increased by 20~62%.

• Journal of Aerospace System Engineering
• /
• v.11 no.2
• /
• pp.9-15
• /
• 2017

In order to verify the possiblity of improving the combustion performance of ethanol using zeolite catalyst and the characteristics of nitrogen oxides and carbon monoxide emission, micro gas turbine experiments were performed using catalytic reaction products, ethanol and kerosene as fuels and the results were compared. The thrust of the catalytic reaction product was lower than that of kerosene, but it was improved by 5% on average compared with the use of ethanol. Nitrogen oxides and carbon monoxide emissions of the catalytic reaction products were measured to be very low overall compared to kerosene. As a result, when the ethanol was reformed using the zeolite catalyst, the engine performance could be improved while maintaining the environment friendliness of the ethanol.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.06a
• /
• pp.325-325
• /
• 2008

스크린 프린팅에 의한 압전 후막은 MEMS 공정을 이용하여 마이크로 펌프, 마이크로 벨브, 마이크로 센서, 마이크로 로봇 등 여러 초소형 기계부품에 응용되고 있으며, Sol-Gel, PLD를 이용해 증착된 막 등에 비해 수십${\mu}m$의 비교적 두꺼운 막을 형성시킬 수 있는 장점을 가지고 있다. 그러나 실리콘 기판을 사용하여 스크린 프린팅으로 형성된 압전 후막의 경우, 공정상 바인더를 연소시키는 과정을 거치게 되므로, 밀집된(Dense) 구조를 가지는 막을 만들기가 어렵다. 이로 인해 스크린 프린팅에 의한 후막은 전기적 특성 및 기계적 특성이 떨어지는 경향이 있다. 본 연구에서는 스크린 프린팅에 의한 압전 후막의 밀집된 구조 및 특성을 향상시키기 위해 0.01Pb$(Mg_{1/2}W_{1/2})$O3-0.41Pb$(Ni_{1/3}Nb_{2/3})O_3-0.35PbTiO_3-0.23PbZrO_3$의 powder와 Attrition 밀링 처리된 powder를 비율별로 혼합하여 입자의 크기를 변화시켜 막의 충진 밀도를 향상시켰으며, 열처리 효과를 극대화시키기 위해 RTA(Rapidly Thermal Annealing)를 통해 열처리 하였다. Attrition 밀링에 의한 파우더를 각각 비율별로 100%, 50%, 25%로 혼합하여 만든 압전 세라믹 페이스트는 P-type(100)Si Wafer sample 위에 $1{\mu}m$의 하부전극용($1100^{\circ}C$) Ag 전극을 screen print하여 소결했다. 그리고 다시 전극이 형성된 Si wafer 위에 스크린 프린팅하고, 건조 한 후 RTA로 300초 동안 열처리 한 결과 밀집된 구조를 가지는 압전 후막을 제작 수 있었다.