• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.631-632
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• 2005

대부분의 고압송전선은 알루미늄도체와 강심코어로 구성된 ACSR(Aluminum Conductor Steel Reinforced) 계통으로 건설되었다. 강심코어는 고탄소강으로 전선의 하중을 담당하며 알루미늄은 도체로 사용되고 있다. ACSR $410mm^2$ 가공송전의 온도와 전류량, 외기조건(온도, 풍속, 풍향각)과의 관계를 규명하는 것은 송전용량과 승전효율을 증진하는데 필수적이다. 전선온도는 전류량에 따라 직선적으로 변화하며 풍속 0.5 m/s와 태양열의 흡수가 없다고 가정하면 "전선온도($^{\circ}C$) = -0.3143 + 0.077$\times$전류랑(A)"의 관계를 가진다. 전류랑 852A에서 풍속에 따라 전선의 표면부와 강심부의 망사온도차는 감소하였다. 풍속 20m/s에서의 방사온도차는 약 $1.4^{\circ}C$로 나타났다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.6
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• pp.69-74
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• 2023

In this paper we review techniques for building and analyzing wavelets on irregular point sets in one and two dimensions. In particular we focus on subdivision schemes and commutation. Subdivision means the skill that approximates the initial lines or mesh into a tender curve or a curved surface by continuous partitioning operation. The key to generalizing wavelet constructions to non-traditional settings is the use of generalized subdivision. The first generation setting is already connected with subdivision schemes, but they become even more important in the construction of second generation wavelets. Subdivision schemes provide fast algorithms, create a natural multi-resolution structure, and yield the underlying scaling functions and wavelets we seek.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.487-490
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• 2008

Field collected larvae inside the pumpkin fruit in Jinan, Chonbuk Province were kept in the laboratory at $24{\pm}2^{\circ}C$, RH $65{\pm}5%$, and 14L:10D until they pupated and eclosed. Adults were fed with dry-milk based diet. Mating behavior was observed when they were 40 days old in a field cage at dusk in July and October, 2008. Wing vibration in male took place under the light intensity of 200 lux-20 lux, however, most commonly under 30 lux. Mounting between male and female was observed under 150 lux-30 lux after the act of wing vibration, also most frequently under 30 lux. Copulation occurred under 150 lux-20 lux. Females approached face to face to males which had been engaged in wing vibration and the copulation was successful for up to 64%. Copulation never occurred when a female positioned in front or at side of the male that was not engaged in wing vibration.

• Journal of the Korean Graphic Arts Communication Society
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• v.31 no.1
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• pp.1-14
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• 2013

Screen printing is a printing method with flexible plate surface characteristics. In addition, since the appearance of electronics industry the screen printing has been demanding high quality and definition. However, Screen printing is a method for taking ink through mesh opening because screen mesh tends to restrict quality of screen printing. In particular, the biggest problem compared with other printing type is halftone reproduction characteristics. Halftone reproduction characteristics for screen printing depend on screen mesh and opening. Dot losses or dot gains are observed through various types of screen mesh because thread of screen mesh interfere with the movement of the ink. Excessive dot losses or gains can affect the tonal range. Furthermore, this problem can result in other problem such as bad contrast and gray balance. Therefore, it is an important factor to use proper screen mesh for halftone screen printing. However, domestic screen printing industry relies on worker's experience in field rather than depending on objective data although standardized specifications and optimal printing conditions are required for screen printing. For this reason, it is important to stipulate standard condition for domestic screen printing industry. Therefore, it was examined to find tonal range by mesh opening in halftone prints process of screen printing used domestic paper and ink in this study. In addition, TVI(Tone Value Increase) characteristic was observed by comparing to the manuscripts and prints of the dot area ratio. Furthermore, contrast value and gray balance were confirmed for each condition of the printout. Conditions for the proper selection of screen mesh screen for the quality of the prints were also examined, compared with the international standard of screen printing, ISO 12647-5.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.235-242
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• 1985

The mechanics of the walking shrimps is useful to clarify the fishing mechanisms in relation to the fishing gears. The gaiting behaviour concerning step positions and step timings on the flat board and the nettings, 16, 23 and 37mm in mesh size were experimented in the aquarium using video camera from June to October, 1984. It was found that the irregular movements of walking legs in step positions and step patterns were appeared on the nettings more than the flat surface due to the absence of mechanical contact with the substrates. The mean stride length and coefficient of variation of the periods in the walking shrimps on the flat board were significantly different from those values on the nettings, However, the velocity, the period and the ratio of forestroke to backstroke were unsteadily changed with the carapace length, and showed little difference under the four conditions. The mean phase difference on the flat board was greater than those values on the nettings which were decreased, while standard deviation on the flat board was smaller than those values on the nettings which were increased with increasing in mesh size.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.2
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• pp.26-36
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• 1999

In this paper, the novel scheme of OAM performance management function is proposed to supply the most of network resources and reliable services by processing data having various QoS(quality of service) in the view of cell loss and cell delay of ATM networks Also, the special fields of OAM cell are defined in order to improve correlate control, operation, and management technique between networks which is required to flexibility and precision control as detecting the performance information of the variable networks periodically. The proposed OAM function, the input/output function of cell, and the interface function of the accessory device which is likely to the memory/CPU are designed to ASIC. The designed chip is carried out the back-end simulation using Verilog-XL simulator of Cadence. In result, it is able to performs an accurate control in $2{\mu}s$.

• Journal of Technologic Dentistry
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• v.42 no.2
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• pp.91-98
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• 2020

Purpose: This study is to compare the flexural strength and modulus by inserting a mesh and stick type fiberglass reinforcement into resin specimens. Methods: Wax specimens (length 64 mm, width 39 mm, thickness 5 mm) are prepared according to ISO 20795-1:2013. Mesh type and stick type glass fiber reinforcements were prepared. The prepared wax specimens were used plaster and flask for investment. The flask was separated and the wax was removed. The heat curing resin was injected into the flask, and then a mesh type and stick type fiberglass reinforcement were inserted. The prepared resin specimen was cut into three equal parts (length 64 mm, width 10 mm, thickness 3.3 mm). The mesh type glass fiber reinforcement (MT group) and the stick type glass fiber reinforcement (ST group) were classified into two groups. The prepared specimen was measured using a universal testing machine (UTM). The data were analyzed by Mann-Whitney U test, and the significance level was set to 0.05. Results: In the flexural strength, the ST group was higher than the MT group, and there was a significant difference between the two groups (p<0.05). In the flexural modulus, the ST group was higher than the MT group, and there was a significant difference between the two groups (p<0.05). Conclusion: The stick-type glass fiber inreased the flexural strength than the mesh-type glass fiber reinforcement.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.3
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• pp.46-52
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• 2008

BGP is an exterior routing protocol which exchanges routing information between ASs in ISP or large networks. It is necessary for the BGP to provide traffic enforcement among ASs, for an End-to-End traffic engineering capability in the Internet. However, traditional BGP-4 is lack of end-to-end traffic engineering capability because the policy-based routing affects the traffic only between directly-connected neighbor ASs. This paper proposes an extended BGP routing algorithm to achieve an End-to-End traffic engineering capability. This new method does not require an additional BGP message type, nor change a structure of existing routing table. It only extended the operation of UPDATE message with AS_PATH attribute, which is well-known mandatory. Simulation shows that the new BGP algorithm improves the packet delay and packet loss without the problem of backward compatibility.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.3 s.30
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• pp.79-89
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• 2004

Despite of a huge amount of GIS data were distributed in the private sectors, they were gradually decayed due to lack of the legal preparation or civilian data distribution channels. In order to solve these problems this study was mainly focused on the civilian GIS data distribution and demonstrated a proposed direction through the requested questionnaire and analysis of the civilian enterprises and public sectors for the favorable civilian GIS distribution flow. The implementation of the civilian GIS data distribution center(provisional name) was proposed fir the civilian GIS distribution flow because of the fact that civilian sectors were seriously requested to build and to operate the civilian GIS distribution organization through the result of the requested questionnaire. The requested questionnaire items were selected as the civilian enterprises distribution, data implementation and management, low and regulations, NGIS distribution network business, and civilian GIS distribution renter build to activate and to participate civilian GIS distribution. Therefore, three implementation models and three implementation operation were proposed to guide a roll of the civilian GIS data distribution center and the distribution boundaries.

• Korean Journal of Materials Research
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• v.9 no.9
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• pp.913-918
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• 1999

As an alternative evaluation method of electromagnetic shielding properties, the material parameters are considered in determining the qualitative value of shielding effectiveness. The specimens are metallized nylon fabrics with the thickness of about 0.1 mm and the electrical conductivities in the range from 6.4$\times$10~2.4$\times$10(sup)5 mhos/m. On the basis of shielding theory, the shielding effectiveness (which is a sum of reflection loss and absorption loss) has been determined from the material parameters of the barrier sheets. For the conductive fabrics, the dominant shield mechanism is predicted to be reflection loss, which shows an increasing function of electrical conductivity. Comparing these theoretical value with the directly measured surface impedances, the error range is found to be within 10 dB, which demonstrates that the proposed material-parameters method can be a convenient way to determine the electromagnetic shielding properties.