• 대한방사선기술학회지:방사선기술과학
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• 제46권2호
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• pp.99-106
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• 2023

The height of the table should be considered important during computed tomography (CT) examination, but according to previous studies, not all radiology technologists set the table at the patient's center at the examination, which affects the exposure dose and image quality received by the patient. Therefore, this study intends to study the image quality exposure dose according to the height of the table to realize the optimal image quality and dose during the brain CT scan. The head phantom images were acquired using Philips Brilliance iCT 256. When the image was acquired, the table height was adjusted to 815, 865, 915, 965, 1015, and 1030 mm, respectively, and each scan was performed 3 times for each height. For the exposure dose measurement, optically stimulated luminescence dosimeter (OSLD) was attached to the front, side, eye, and thyroid gland of the head phantom. In the signal to noise ratio (SNR) measurement result, The SNR values for each table height were all lower than 915 mm. As a result of exposure dose, the exposure dose on each area increased as the table height decreased. The height of the table has a close relationship with the patient's radiation exposure dose in the CT scan.

• 한국식생활문화학회지
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• 제6권3호
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• pp.265-274
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• 1991

To analyze wedding feast dishes of king and royal prince of Chosun Dynasty (1866, 1906), the author studied historic book Gare Dogam Euigwae, in which the wedding feast dishes of King and Prince in Chosun Dynasty were described. The results obtained from the study were as follows, 1. Dish materials used for wedding ceremony in the year of 1866 was same as that of the year 1749. 2. Dish materials used for wedding ceremony in the year of 1906 was quit different that of the year 1749. 3. Dish materials used for main table(연상(宴床)), second table(좌협상(左挾床)), third table(우협상(右挾床)), and fourth table(면협상(面挾床)) was the same as that of from the year 1651 till 1906. 4. Dish materials used for a small round table(초미(初味)), another table(이미(二味)), and the other table(삼미(三味)) was the same as that of from the year 1749 till 1906. 5. A large boiled beef(대선(大膳)) and a small boiled beef(소선(小膳)) were in the year 1819 and 1906.

• 한국통신학회논문지
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• 제30권4C호
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• pp.247-252
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• 2005

현재 DVD 시스템의 채널에서 디코더는 16비트 입력을 받아 8비트 데이터 심볼을 복원한다. 이러한 DVD용 변조 코드는 주 테이블(main table)과 부 테이블(sub table)로 이루어진 EFMplus 코드를 사용한다. 본 논문에서는 디코더 구현시 필요한 코드 테이블의 크기를 줄이기 위해 EFMplus 코드를 3개의 그룹으로 나눈 후 각 코드의 가지 수를 줄이는 방법을 제안하고 이 코드 테이블을 이용하여 디코더를 구현하였다. 이 방식은 기존의 테이블을 이용하여 디코딩할 때 필요한 코드 수 1376개를 750개로 약 $46\%$정도 감소시켜 EFMplus 코드를 구현할 때 필요한 ROM의 크기를 약 2배 정도 줄였다.

• 대한물리의학회지
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• 제8권3호
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• pp.289-294
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• 2013

PURPOSE: The purpose of this study was to examine differences in erect spinae activities at different height of table during ultrasound therapy in order to propose a optimum work environment. METHODS: Twenty five healthy adult males and females volunteered to participate in this study. EMG signals of both erector spinae(T10, T12, L2, L4) were recorded throught the surface electromyography system at different height of table(45cm, 56.2cm, 67.5cm) during ultrasound therapy work. RESULTS: The higher table heights was, the lower %RVC of the T10, T12, L2, L4 erect spinae at both sides. The left and right T10, T12 and the left L4 showed significant differences. The lower the spinal level was, the higher %RVC of both erect spinae at 45cm, 56.2cm, 67.5cm. The left erect spinae at 56.2cm, right erect spinae at 45cm, 67.5cm showed significant differences. CONCLUSION: The muscle activities of both erect spinae decreased at higher table height and increased lower spinal level. We identified lower table height are risk factor of spine work related musculoskeletal disorders.

• Smart Structures and Systems
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• 제14권6호
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• pp.1055-1079
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• 2014

Substructure shake table testing is a class of real-time hybrid simulation (RTHS). It combines shake table tests of substructures with real-time computational simulation of the remaining part of the structure to assess dynamic response of the entire structure. Unlike in the conventional hybrid simulation, substructure shake table testing imposes acceleration compatibilities at substructure boundaries. However, acceleration tracking of shake tables is extremely challenging, and it is not possible to produce perfect acceleration tracking without time delay. If responses of the experimental substructure have high correlation with ground accelerations, response errors are inevitably induced by the erroneous input acceleration. Feeding the erroneous responses into the RTHS procedure will deteriorate the simulation results. This study presents a set of techniques to enable reliable substructure shake table testing. The developed techniques include compensation techniques for errors induced by imperfect input acceleration of shake tables, model-based actuator delay compensation with state observer, and force correction to eliminate process and measurement noises. These techniques are experimentally investigated through RTHS using a uni-axial shake table and three-story steel frame structure at the Johns Hopkins University. The simulation results showed that substructure shake table testing with the developed compensation techniques provides an accurate and reliable means to simulate the dynamic responses of the entire structure under earthquake excitations.

• 대한기계학회논문집A
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• 제31권12호
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• pp.1214-1220
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• 2007

The vertical roller mill, which performs the grinding and partly blending of raw material, is the one of the important machine to produce ordinary portland cement. It has been reported that an unexpected fatigue failure occurred in a table liner in the course of grinding portland cement. The life of table liner is estimated to $4{\times}10^7$ cycles in the design stage, but at the field, when its operating time reaches to $2{\times}10^6{\sim}8{\times}10^6$ cycles, the fracture of table liner begins to be found. The fracture of table liner is initiated from the outside edge of grinding path contacting with the grinding roller. Its maintenance normally take 30 % of the total maintenance costs of the roller mill. Therefore, this study shows the clarification of the reasons occurring the fatal destruction of the table liner by fatigue fracture analysis utilizing fracture mechanics and by the finite element method. And, the results from Goodman diagram illustrate relationship of including information on the transition between tensile and bending fatigue strength in the fatigue characterization of table liner.

• Journal of Korean Biological Nursing Science
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• 제11권1호
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• pp.1-13
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• 2009

Purpose: This study was conducted to evaluate the effects of table tennis program on self efficacy, cardiopulmonary function, serum lipids, catalase activity in the physical disabilities. Method: Physical disabilities were allocated to one of two groups: control group (n=7), experiment group (n=8). The experiment group took table tennis program four times a week for 12 weeks. Self efficacy was measured by questionnaire. Serum lipid profiles, catalase and cardiopulmonary function were checked after the exercise program and compared with pre-exercise data. Result: Self efficacy was significantly higher in the table tennis group. Maximum oxygen consumption and forced vital capacity were significantly increased and heart rate at rest was decreased in the table tennis group. Total cholesterol and triglyceride were decreased in the table tennis group. There was no significant change in catalase activity between two groups. Conclusion: These results indicate that table tennis program has positive effects on the health of the physical disabilities by improving the self efficacy and cardiopulmonary function and serum cholesterol profile.

• 한국가구학회지
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• 제25권4호
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• pp.288-296
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• 2014

The approach of using the structure of the Joseon Dynasty Zen tradition we design a piece of table for outdoor camping is a necessity in modern culture as continuing to develop this research. Analyzing outdoor and camping equipment according to the time change, we focus on the study table for outdoor camping can apply the structure of the elbow. Outdoor supply is also overlaid with the change, while changing in the picnic and camping camp sensibility that was taking advantage of the individuality of each of the general camp. However, it is a surface camp that Korean culture is not to build up the camp culture that has been fixed camp culture of the world in the only development, following the camp trend of European and American. In an attempt to adhere to the trend of Korea currently camped, camping outdoor products that apply the beauty of Korea with a combination of new modern representation tradition and our culture has designed research. I have designed the camp outdoor table based on the contents mentioned above. For the design of this time, it is now possible to use appropriately in accordance with the outdoor environment conditions that are designed to upright seat sharing table in the market tables for camping and to be divided into the seat and upright.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.669-673
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• 2007

In this study, real-time hybrid test using a shaking table for the control performance evaluation of a U-shaped TLCD controlling the response of earthquake-excited building structure is experimentally implemented. In the test, the building structure is used as a numerical part, on which a U-shaped TLCD adopted as an experimental part was installed to reduceits response. At first, the force that is acting between a TLCD and building structure is measured from the load cell attached on shaking table and is fed-back to the computer to control the motion of shaking table. Then, the shaking table is so driven that the error between the interface acceleration computed from the numerical building structure with the excitations of earthquake and the fed-back interface force and that measured from the shaking table. The control efficiency of the TLCD used in this paper is experimentally confirmed by implementing this process of shaking table experiment on real-time.

• 한국정밀공학회지
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• 제27권4호
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• pp.7-13
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• 2010

Linear motors are efficient mechanism that offers high speed and positioning accuracy. By eliminating mechanical transmission mechanisms, much higher speeds and greater acceleration can be achieved without backlash or excessive friction. However, an important disadvantage of linear motor system is its high power loss and heating up of motor and neighboring machine components on operation. Therefore, it is necessary to design moving table with high stiffness, high efficiency and light weight construction. This paper presents the development of moving table using composite material. In order to develop light weight construction of moving table, finite element analysis is performed to find best moving table construction and composite stacking sequence. NASTRAN and MINITAB were used as the optimizer. A prototype for the moving table using composite material was created.