• 한국자동차공학회논문집
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• 제9권2호
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• pp.11-18
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• 2001

To clarify the influence of SAC shape of hole-type diesel nozzle on injection characteristics and spray patterns, the injection rate of three nozzle types(standard SAC nozzle, Needle-cut VCO nozzle and VCO nozzle) were measured by Zeuch's method and pictures of the sprays were taken by CCD camera. As the pump speed became higher, the injection characteristics of the three nozzles were different. Injection rate and perssure curves at the high pressure pipe in Needle-cut VCO nozzle were much more similar to the VCO nozzle than those of the SAC nozzle. When the needle was at pre-lift period for all speeds, the spray of the Needle-cut VCO nozzle showed almost the same shape as the SAC type nozzle. There was no differense in spray pattern at the needle full-lift periods.

• 한국분무공학회지
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• 제8권2호
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• pp.24-30
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• 2003

An experimental study was performed to investigate the influence factors of drop formation in electrohydrodynamic atomization. The mode of electrohydrodynamic atomization depended on the various factors such as the flow rate of the liquid, the inner diameter of the nozzle, the distance between the nozzle tip and the ground electrode, the shape of the ground electrode. and the applied high voltage. This work was performed to investigate the experimental analysis for the flow pattern visualization of droplets, and the relationship between voltage application and the behavior of liquid atomization. Uniform drops of different sizes can be obtained at the inception of the spindle mode by charging the flow rate and the electric field. The drop size also decreased when the flow rate was raised for the spindle mode. The whipping motion occurred beyond 7kV and before the corona started to take effect.

• 농업과학연구
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• 제27권2호
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• pp.125-134
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• 2000

This observation was to investigate the influence of raw organic matter incorporated into soil at various rates on hydraulic conductivity and elution of solute throughout soil column. Generally the organic matter content in a practical agricultural field was approximately 3%. However, the application rate of organic matter in the field tends to rapidly increase in these days. Therefore, we raised the application rate of organic matter up to 10% in this investigation. From the experiment, we found that the hydraulic conductivities rapidly decreased with increasing rate of organic matter as well as rapid decrease in total volume of eluent during the same period. And electrical conductivities in the effluent significantly decreased after 2 pore volume, resulting in approaching to the criteria of saline soli. From this we could assume that the organic matter may influence the crop growth in the beginning. However excessive irrigation in the field may cause saturation of soil leading to reduction of soil. Therefore, there must be a management methods in application of organic matter with respect to soil water control.

• 한국정밀공학회지
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• 제8권1호
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• pp.74-83
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• 1991

A study on the Correlation of Orthogonal Cutting Parameter (Cutting speed, Depth of cut, Feed Rate) and Acoustic Emission Signal. It is well known that acoustic emission (AE) is the emission of elastic wave resulting from the deformation and fracture of materials. This study estabished correlation of orthogonal cutting parameter and AE signal, and researched into in-process monitoring of tool wear and failure. The results are as follow; 1. AE RMS was under the influence of cutting speed but hardly influenced by depth of cut and feed rate. 2. AE RMS was under the influence of flank wear. 3. AE count rate increased by increased cutting speed. 4. AE RMS value was rapidly increased in 130 m flank wear.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.1124-1128
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• 2005

The duration of a construction project is not only a key element for taking a new order, but also a strict yardstick to determine certain project successful or not. However, since construction project is basically outdoor job and most of the activities are proceeded out-air, no matter how the schedule plan has been established accurately, actual project proceeds due to the weather condition, beyond anyone's control. In this paper, the functional relationship between work productivity rate and weather elements is suggested by regression analysis. Difference of the relationship and influence of weather due to the seasonal group are also revealed. With these results, by simulating actual weather data and generating weather forecast through historical data, more accurate schedule would be obtained.

• 한국세라믹학회지
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• 제21권3호
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• pp.209-216
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• 1984

The influence of the particle size of quartz and the change of cooling rate to the strength of conventional triaxial porcelain was studied, . The results indicate that 1. The residual quartz content was increased by particle size increasing. And the strength was increased by increas-ing residual quartz content which increased the total stress in the specimen. But the influence of residual quartz was lessened by the extent of crack between quartz particle and glass matrix 2. In order to increase the strength of the body fast cooling is suitable to small quartz particle and slow cooling is suitable to large quartz particle.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 추계학술대회 논문집
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• pp.319-323
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• 2002

Recently, new polishing system which was made by magnetic intelligent compound (MAGIC) was invented and, the study is going on for practical use the analysis of factors, that is, the kind of polishing grain, composition ratio of wheel elements, machining frequency, polishing pressure, which the main influence for polishing efficiency are the first step. In this study, analyzed influence of wheel raw material composition ratio on surface roughness.

• 보건행정학회지
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• 제26권3호
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• pp.226-232
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• 2016

Background: This study was conducted to analyze the influence of socioeconomic characteristics of community on the food insecurity under the control of personal socioeconomic factors which may be influence to the food security. Methods: Food insecurity and individual socioeconomic characteristics were obtained from 2012 community health survey. Socioeconomic characteristics of communities were extracted from the data of Statistics Korea and local governments. Personal socioeconomic factors were sex, age, educational status, job, and monthly family income. Socioeconomic characteristics of communities were administrative district (urban vs. rural), senior population rate, degree of financial self reliance, degree of financial independence, portion of welfare budget, number of welfare facilities, and unemployment rate. We analysed the relationships between the food insecurity and socioeconomic characteristics of community using multi-level analysis under the control of personal characteristics. Results: On personal level age, sex, education status, and monthly family income were related with food insecurity. On community level administrative district (urban vs. rural), degree of financial independence, unemployment rate, and proportion of welfare budget among local general government accounts were related to individual food insecurity. Rural area, district with low levels of financial independence, low portion of welfare budget, and greater unemployment rate showed a higher level of food insecurity. Conclusion: To reduce the level of food insecurity in a community it is necessary to decrease the unemployment rate, in addition to providing support from the central government by increasing the proportion of the welfare budget so that both factors contribute to raising the degree of financial independence.

• 한국식생활문화학회지
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• 제16권5호
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• pp.483-491
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• 2001

Traditional Korean beverage can be divided into Jang, Gahl Soo, Mi Su, Soo Jung Gwa, Shick Hae, Tahng, Hwa Chae, Sook Su, and Tea according to ingredients and how it is proccessed. The purpose of this study was to investigate the Korean beverage percetpion and to analyze the factors (sociodemographic factors and life-style related factors) which influence percetpion of Korean beverage. Questionnaries were hand delivered to 2,200 subject residing in Seoul and 1,884 questionnaris were collected : resulting in 84% response rate. Statistical data analysis was completed using SAS Package program for the analysis of covariance(ANOCOVA).The results are as follows: (a) Survey on Korean beverage perception showed that the recognition rates of ShickHae(58.4%), Cition Tea(53.5%), Sung Nung(48.7%) and Soo Jung Gwa(40.8%) were high, whereas those for Tahng, Jang, and Gahl Soo were low.(b) About 40% of respondents performing 4 kinds of Korean traditional ceremony a year The percentage that reported they purchased Korean beverages was 44.0%, higher than the 38.5% that answered they made Korean beverage at home.(c) In analyzing the factors which influence beverage perception, the sociodemographic factors variously influenced perception rate depending on beverage. Age and sex had influenced on perception rate of Shick Hae and Donggulre Tea. Income level influenced on the perception rate of Sung Nung and Citron Tea. Sociodemograhpic factors like senior over 50s, female and extended family size had positive influence on the perception rate.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권3호
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• pp.1-14
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• 2014

It is necessary to decide the pumping rate and pumping well location together with the capture zone in order to determine an appropriate groundwater remediation strategy to manage the contaminated groundwater. The relationship between the capture zone and the drawdown radius of influence ($ROI_s$) was considered. $ROI_{cs}$ is defined as the distance where the criteria of drawdown is cs meter from pumping well in this paper. A method to decide the required pumping rate for the remediation of contaminated groundwater in order to create appropriate $ROI_{cs}$ is suggested by using the Theis equation (1935) and Cooper-Jacob equation (1946). It was shown in this study that $ROI_{cs}$ is in proportion to the pumping rate and the criteria of drawdown, which decides $ROI_{cs}$, is inversely proportional to Ti value (transmissivity ${\times}$ hydraulic gradient). The pumping rate which creates the required $ROI_{cs}$ could be planned through the relationship between the $ROI_{cs}$ and pumping rates ($ROI_{cs}$-Q curve) of the field sites 1, 2 and 3. If the drawdown is investigated along with Ti value and pumping rate at a specific site where pump and treat remediation is planned, it is expected that the required criteria of drawdown can be evaluated by using the relationship between the cs and Ti (cs-Ti curve).