• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.476-479
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• 2000

In this study, mesh-type PECVD system was suggested to minimize the hydrogen concentration. The main structural difference between the triode system and a conventional system is that a mesh was attached to the substrate holding electrode. We investigated several conditions to compare with conventional PECVD. The main effect of mesh was to minimize the substrate damage by ion bombardment and to enhance the surface reaction to induce hydrogen desorption. It was also found that hydrogen concentration decreased but deposition rate increased as increasing applied dias. Applied DC bias enhanced sputtering process. Intense ion bombardment causes the weakly bonded hydrogen or hydrogen-containing species to leave the growing film and increased adatom mobility. Furthermore, addition of hydrogen gas enhance the surface diffusion of adatom. The structural properties of poly-Si films were analyzed by scanning electron microscopy(SEM).

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.411-416
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• 2016

Existing moving robots has several kinds of moving method; using wheel, jointed leg structure and so on. Wheel type can be operated by DC motor so it is simple and efficient. However, it is not appropriate to pass irregular terrain and obstacle. Leg structure type has an advantage in those cases. Generally, Leg structure is operated by several servo motors attached to each joint. It makes a robot heavier and more complicate due to increase of the degree of freedom. However, by using Theo Jansen Mechanism, one (or more) leg have only single-degree of freedom and can be operated by only one DC motor. So leg structure using Theo Jansen Mechanism will be good choice if robots have to be mass-produced. This paper describes the following a walking robot designed and produced based on Theo Jansen Mechanism, simulating process of Theo Jansen leg structure using Edison m.Sketch and how to solve several of discovered problem of the robot.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.178-187
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• 2000

The tillage operation by rotary implements is widely done in Korea. In the case of rotary implements, the tillage depth control system is one of important implement control systems. A contact type-sensor for measurement of the ground height was designed and fabricated to evaluate the possibility of application of the sensor on the tillage depth control system. Indoor experiments were conducted to obtain static and dynamic detection characteristics of the sensor under various conditions; 1) several moisture contents for four soil samples, 2) two soil surfaces with a designed configuration, 3) four heights of the sensor from the soil surface, 4) five traveling speeds of the carrier on which the sensor was attached, and so on. The experimental results showed the detection characteristics of the sensor sufficient as the ground height sensor of the tillage depth control system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.190-191
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• 2021

This study is conducted to provide a method to estimate the setting time and early age compressive strength using D type durometer.Test results indicated that the use of D type Durometer attached with modified needle, which was designed to secure improved accuracy in setting and compressive strength, enables to estimate setting time and the compressive strength at early age.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.281-285
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• 2001

This study was carried out to improve the performance of heat recovery device attached to exhaust gas flue connected to combustion chamber of greenhouse heating system. Three different units were prepared for the comparison of heat recovery performance; AB-type(control unit) is exactly the same with the typical one fabricated for previous study of analyzing heat recovery performance in greenhouse heating system, other two types(C-type and D-type) modified from the control unit are different in the aspects of airflow direction(U-turn airflow) and pipe arrangement. The results are summarized as follows; 1. In the case of Type-AB, when considering the initial cost and current electricity fee required for system operation, it is expected that one or two years at most would be enough to return the whole cost invested. 2. Type-C and Type-D, basically different with Type-AB in the aspect of airflow pattern, are not sensitive to the change of blower capacity with higher than $25\;m^{3}/min$. Therefore, heat recovery performance was not improved so significantly with the increment of blower capacity. This is assumed to be that air flow resistance in high air capacity reduces the heat exchange rate as well. Never the less, compared with control unit, resultant heat recovery rate in Type-C and Type-D were improved by about 5% and 13%, respectively. 3. Desirable blower capacity for these heat recovery units experimented are expected to be about $25\;m^{3}/min$, and at the proper blower capacity, U-turn airflow units showed better heat recovery performance than control unit. But, without regard to the type of heat recovery unit, it is recommended that comprehensive consideration of system's physical factors such as pipe arrangement density, unit pipe length and pipe thickness, etc., are required for the optimization of heat recovery system in the aspects of not only energy conservation but economic system design.

• Journal of Korean Society on Water Environment
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• v.28 no.6
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• pp.917-922
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• 2012

In order to improve applicability of a microbial fuel cell the laboratory-scaled study has been performed by adopting an air-cathode MFC system with high concentrated anaerobic slugies in this study. The concentrations of microbes are grouped into three types, Type A (TS 1.7%), Type B (TS 1.1%) and Type C (TS 0.51%). The open circuit voltage $(V_{oc})$ characteristics showed that the medium microbes concentration of 1.10% (Type B) kept a constant voltage of 1.0 V for 150 hours, which showed the longest time among three types (Type A and Type C). The discharge charge curves for a closed circuit with $500 \Omega$ also showed that Type B generated a stable discharge voltage of 0.8 V for a longer time as in the open circuit voltage case. This could be explained by the relatively large amount of the attached microbes. Under the $V_{oc}$condition the COD removal efficiency of Type B was found to be low for a long time, but those of Type A and C were found to be high for a short period of time. Therefore, the suspended microbes could decrease the coulombic efficiency. It was concluded that the high $V_{oc}$ was caused by low COD and the $V_{oc}$ became low after the COD removal. The COD reduction resulted in an unstable and low working voltage. From the polarization characteristics Type A was found to show the highest power density of $193\;mW/m^2$ with a fill factor of 0.127 due to the relatively high remaining COD even after the MFC reaction.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.4
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• pp.449-456
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• 2015

In this paper, attaching various damping plates to the cylindrical structure and performing numerical simulations try to study heave RAO and natural period for cylinder. Most of all, we identified heave RAO of the cylinder by simulations of the motion and the wave. And then, we performed numerical simulations by changing the size and shape of heave damping plate attached to the cylinder and reviewed the heave RAO and natural period for each case. The conclusions of this research are as follows. Firstly, the natural period of cylindrical structure is increased by attached to the cylinder with heave damping plate and the heave RAO of cylindrical structure is reduced in the peak period for incident wave by attached to the cylinder with from the size of 1.30D for heave damping plate. Secondly, circular plate has long natural period than Y-type plate in all of these sections. Finally, the motion response spectrum considering the marine environment of Piranema field was identified as the heave motion of cylindrical structure is remarkably reduced with both circular plate and Y-type plate in the peak period for incident wave.

• Journal of the Korea Fashion and Costume Design Association
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• v.7 no.1
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• pp.85-99
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• 2005

This study is to know the blue jean image according to type and its constituting element. and also to analyze image according to the sex of wearers and recognizers, the existence and nonexistence of blue jean affect the wearer's body type. Thirty-six photo stimulus material attached to men and women wearers selected as people of skinny types, average types and fat types, were seen to 1,354 men and women university students and had them measure blue jean image and element of twenty one items. 1, The blue jean image was different according to design type. The broad blue jean was active but it looked fat. The bleached blue jean matched with any clothing. The legs looked long. Painting blue jean seemed o be new, colorful, splendid, The torn blue jean appeared to match with any clothing. And lap seam blue jean was active but the waist seemed as thick image. 2, In the wearer's body type, the jeans image strengthen the wearer's body image. The legs looked long. The fat type appeared high in the item like this; they looked fat. The waist looked thick. It was courageous and casual. It appeared that the fat element appeared as blue jean image of fat type. 3, In the relation of wearer's sex and blue jean image, when the wearers were men, the image was passable. It matched with anyone. It was splendid and refined. The legs appeared long. When the wearers were women, the blue jean image was economic. It had no relation with a fashion. It was active, comfortable, free, casual and fat. The waist looked thick. In image element, activity and fat element appeared as a main element of the blue jean image.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.3
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• pp.153-166
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• 1991

Laver is sea weeds that might have been eaten by Korean people since ancient times. The begining of laver culture is not known exactly, but it appears to be prehistoric age. Some laver culture complexes have been built in southern coastal sea of Korea around 1910. This paper was considered about the origin and development process of Korean laver culture industry by investigating Korean and Asian old books concerned. The results are as follows. 1. According to the Korean old books ralated, the name of laver is classified into 10kinds. Gim and Hae-I were called by Korean. Gim means weeds and Hae-I means the manufactured laver by cutting and drying like paper sheet. Ja-Chae and Hae-Tae are come from Chinese, however they are commonly called by Korean, Japanese and Chinese. Rest six names are come from Chinese botany. 2. As Chinese used laver as medicine for wen, scrofula, fever, vomiting, diarrhoea and. so on, they didn't regard it as foods and took into account an warning by Chinese botany that they could take ill when overeating it. On the other as Korean people have eaten it with pleasure nevertheless the Chinese warning, various foods using laver have been developed. The typical food is rice covering laver sheet. It is also popular to Japanese. 3. Laver culture can be carried out in all coastal seas around Korean peninsula, the best sea area for it is the middle west of south sea. 4. Seopkkoji type is a laver culture method that when branches of tree are put in tidal flat laver sporules are attached and gronm on them. It was begun by Hae-Jak Kun(a group of fishery slaves) on Kwang-Yang bay the most suitable for. laver growth at the beginning of King $Sung-long(1469{\~}1481)$. It is assumed that when Hae-Jak Kun set Oe-Jeon(a sort of fixing fishing gear) to catch tributary fish for king, they could find grown laver attached on Oe-Jeon and invent Seopkkoji type for exclusive laver culture. That was carried out 200 fears earlier than in Japan. Dde-Bal type is more advanced and productive laver culture method with thinly spilt bamboo tied like screen(one end fixed on bottom and other end set free in water), It is assumed that Dde-Bal type was begun in Wan-Do county in King Chull-Jong(1830). All laver culture methods developed were transfered to Japan.

• Journal of the Korean Society of Radiology
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• v.12 no.6
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• pp.769-776
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• 2018

According IEC 60601-1 ed3.1 and IEC 60601-2-45 regulation, diagnostic X-ray equipment should be display to measured and calculated air kerma area product. On the clinical X ray equipment, air kerma area product dosimeter would like to have an evidence for dosimeter accuracy and energy dependency. This study was performed to indirect calibration and energy dependency test for attached type air kerma area product (KAP) dosimeter by RQR standards beam quality. On the RQR5 beam quality, attached KAP dosimeter error showed -7.5%, respectably. On the RQR9 beam quality, attached KAP dosimeter error showed -10.4%, respectably. All RQR beam quality, average absolute error was $8.30%{\pm}2.85%$, respectably. On this study, attached KAP dosimeter was satisfied to IEC 60580 and AAPM TG 190. This calibration method of KAP dosimeter will help to performance maintain for clinical KAP dosimeter.