• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.3
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• pp.259-267
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• 2005

This paper analyzed characteristic of temperature change as well as bottom of tunnel with thermometer according to tunnel length and region during one year. And it measured temperature distribution near tunnel portal. In the paper it was known that tunnel entrance and exit have different characteristic temperature distribution in accordiance with bottom of tunnel per tunnel length. Temperature of tunnel changed from tunnel exit to fifty meter and distribution of tunnel temperature was established uniform regardless of tunnel length. But temperature distribution of tunnel changed in tunnel entrance differ from tunnel exit in the location of one hundred twenty five meter and one hundred fifty meter. Cold air inflowed from tunnel entrance have influenced with the location of one hundred twenty five meter and one hundred fifty meter.

• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.18-23
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• 2006

The influence of the notch length on the stress distribution of mid-bondline and adherend was investigated using elasto-plastic finite element method. The results from the simulation showed that peak stress of mid-bondline decreased markedly as adherend with notch in the middle of lap zone, and the stress in the middle of joint with low stress originally increased evidently. All the peak stresses decreased firstly and increased again as the length of notch increased. The relative higher peak stress appeared at the point near the notch of adherend where might be failed previously during the loading procedure.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.9 s.186
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• pp.127-133
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• 2006

Cold expansion method is used to protect a fatigue fracture from fastener hole in the structure and aerospace industry. Cold expansion is that an oversized tapered mandrel goes through the hole and produces a compressive residual stress as well as plastic deformation around the hole. Here, mandrel shapes are one of the factors which are influenced on the residual stress distribution by cold expansion method. This paper, according to mandrel shapes (diameter of mandrel, length of mandrel and length of taper), we are performed a finite element analysis of residual stress distribution by cold expansion method. From this study, it has been found that diameter of mandrel and length of taper are an important factor which was generated a low compressive residual stress surround of fastener hole by cold expansion method.

• Journal of the Korean Mathematical Society
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• v.40 no.1
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• pp.87-107
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• 2003

In this paper, we consider a discrete time queueing system fed by a superposition of an ON and OFF source with heavy tail ON periods and geometric OFF periods and a D-BMAP (Discrete Batch Markovian Arrival Process). We study the tail behavior of the queue length distribution and both infinite and finite buffer systems are considered. In the infinite buffer case, we show that the asymptotic tail behavior of the queue length of the system is equivalent to that of the same queueing system with the D-BMAP being replaced by a batch renewal process. In the finite buffer case (of buffer size K), we derive upper and lower bounds of the asymptotic behavior of the loss probability as $K\;\longrightarrow\;\infty$.

• Journal of International Academy of Physical Therapy Research
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• v.9 no.3
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• pp.1543-1548
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• 2018

The purpose of this study was to analyze the effects of manual therapy on lower extremity alignment in pelvic malalignment. The subjects were 20 adults with pelvic malalignment. They were divided into two groups: manual therapy group (n=10) and stretching exercise group (n=10). Each group performed the intervention two times per week for 4 weeks. The lower extremity alignment was measured by pelvic deviation, functional leg length inequality, and plantar pressure distribution, which were measured between pre- and post-test. In the result of pelvic deviation, there was a significant difference between the pre- and post-test of the manual therapy group and stretching exercise group. In the result of the functional leg length inequality, there was a significant difference between the pre- and post-test of the manual therapy group. In the result of plantar pressure distribution, there was a significant difference between the pre- and post-test of the manual therapy group. These findings suggest manual therapy improves the pelvic deviation, functional leg length inequality, and plantar pressure distribution in the pelvic malalignment.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.12
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• pp.1588-1595
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• 2000

Natural convection heat transfer in an enclosure with an opening in the right veritcal wall and a heat source at the bottom surface is investigated using a holographic interferometric technique. The effects of the opening length, divider length attached to the top wall, and heater temperature on the temperature distribution are examined. The opening length as well as the divider length greatly affects the degree of inflow and outflow of air. In the case of small opening length, the opening doesnt affect much the upward warm air flow resulting in the symmetric temperature distribution .The upward flow in hindered by the divider resulting in the decrease of heat transfer from the heater region to the upper region. The longest divider shows the highest temperature in the lower region of enclosure. In the case of large opening length, the inward cold flow moves the upward flow to the left direction. Among the cases of different divider length, the case of H(sub)d=0.25H shows the highest temperature in the lower region of enclosure.

• Journal of the Korean Data and Information Science Society
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• v.25 no.1
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• pp.237-244
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• 2014

It is known that the dierence in the length between two location parameters of two random variables is equivalent to the difference in the area between two cumulative distribution functions. In this paper, we suggest two applications by using the difference of distribution functions. The first is that the difference of expectations of a certain function of two continuous random variables such as the differences of two kth moments and two moment generating functions could be defined by using the difference between two univariate distribution functions. The other is that the difference in the volume between two empirical bivariate distribution functions is derived. If their covariance is estimated to be zero, the difference in the volume between two empirical bivariate distribution functions could be defined as the difference in two certain areas.

• Korean Management Science Review
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• v.17 no.3
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• pp.73-95
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• 2000

In Korea, the distribution channel for agricultural products is notorious for its complexity and ineffectiveness. In this sense, the Agricultural Cooperative has tried to clarify the distribution channel and reduce its length. However, there still exist much room for improvements. The Internet shopping mall specific for agricultural product, therefore, is drawing much attention because it can reduce the length of distribution channel drastically and improve effectiveness from the distribution perspective. To test the validity of such Internet-driven shopping mall, we gathered questionnaire data from the Internet based Hannaro Shopping Mall which is run directly by the Agricultural Cooperative. We performed experiments respectively for the two groups of operating personnel and consumers. Experimental results showed that several important factors can be identified which are significant statistically and deemed to have meaningful relationship with performance variables. Our results also showed that the Internet shopping mall has a great potential for improving the effectiveness of the distribution channel of the agricultural products.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1186-1188
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• 1999

When we perform the test related to the power distribution system such as artificial fault test, protective coordination test, distribution automation test in short length test line, Lumped Constant Circuit, a kind of variable impedance, should be attached to the test line in order to make it equivalent to a real line in length electrically. In this paper we designed the positive sequence and zero sequence Lumped Constant Circuit with optimized inductor and resister for the modification of long, 16km, distribution line, when they are attached to the short, 4km, distribution test line.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.4
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• pp.85-93
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• 1996

This study is to make a comparison between the node method and the pipeline method for the analysis of the water distribution systems. For these purposes, the two methods were applied to a pipeline system in series, an artificial distribution network and a real distribution network. The results are as follows. 1. The difference between the results of the two methods was increased with the increase of the hydraulic gradient and the length between two adjacent nodes. 2. When all pipe lengths between two adjacent nodes were larger than 200~300m and have the steep hydraulic gradient, it was found that the results of the two methods showed high differences. 3. The difference between the results of the two methods were negligible in the case of the real distribution system in which only 12% whole pipelines were longer than 30m and the longest pipe length was 850m.