• Journal of KSNVE
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• v.8 no.5
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• pp.807-813
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• 1998

Transmission loss of the simple expansion chamber with multiple inlet and outlet ports is obtained. Transfer matrices which represent the relation between the power variables(pressure and velocity) of inlets and outlets depend on the input relatons as well as the acoustic system parameters(i.e. geometry of the chamber, wall admittance, etc.). The analysis has been performed analytically, including the effects of higher order modes for the 2-inlet/1-outlet, 1-inlet/2-outlet and 2-inlet/2-outlet systems. This study yeilds that phase difference between the inlet ports can significantly increase the transmission loss in low frequency range.

• The Journal of the Acoustical Society of Korea
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• v.19 no.1
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• pp.54-60
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• 2000

There are many works to analyze a simple expansion chamber involving higher order modes. These works are classified to mode matching method, velocity potential method and finite element method. Among these methods, mode matching method has good performance at analyzing a concentric expansion chamber. Generally inlet/outlet pipe cross section area is smaller than middle chamber cross section area. So the number of higher order modes of inlet/outlet pipe can be fewer than that of middle chamber. But mode matching method must use the same number of higher order modes at inlet pipe, middle chamber and outlet pipe. Therefore the redundant modes of inlet/outlet pipe makes the computation time of mode matching method longer. In this paper, the new method, which can select number of each higher order modes of inlet pipe, middle chamber and outlet pipe, was suggested. And this method was compared to conventional mode matching method and finite element method in order to demonstrate the accuracy of the new method and to show that the new method can reduce a calculating time.

• Journal of Veterinary Clinics
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• v.28 no.2
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• pp.262-266
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• 2011

A 4-year-old intact male, Maltese dog weighing 2.2 kg was presented for evaluation of tachypnea and hyperthermia. On initial evaluation, the dog was dyspneic, but alert and responsive. Muffled heart sound was noted with auscultation of the right hemithorax. The radiographic findings were consolidation of the right middle lung lobe, pleural effusion, and abdominal fluid accumulation. Thoracic computed tomography confirmed a contrast-enhancing mass within the right middle lung lobe. Surgical exploration of the thoracic cavity was performed using a right fifth intercostal thoracotomy. Examination of the right lung lobe revealed $360^{\circ}C$ torsion of the right middle lung lobe at the level of the hilus, in a clockwise direction. Lung lobectomy was performed using a thoracoabdominal stapling device with 2.5-mm vascular staples. Full-thickness intestinal biopsy by exploratory laparotomy was taken from the jejunum for histological assessment. Histopathologic examination of the full-thickness intestinal biopsy revealed distended lacteal located within the submucosa of the jejunum. Intestinal lymphangiectasia was resolved with prednisone and low fat diets. Subsequent communication with the owner revealed that the patient was in good health 6 months post-discharge.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.397-400
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• 1999

본 연구에서는 기존의 모드적합법의 단점을 개선하여 각 관에 임의의 모드갯수를 선택할 수 있고, 동심관형 단순확장관의 음향특성뿐만 아니라 입$\cdot$출구가 임의의 위치에 있는 경우에도 모드적합법을 적용할 수 있는 방안을 제시한다. 그리고 제시한 방안으로 프로그램을 작성하여, 각각 임의의 모드와 임의의 입$\cdot$출구의 위치를 가지는 원형 소음기의 4단자 정수를 구하고, 이로부터 임의의 입$\cdot$출구 위치에 따른 소음기의 음향특성을 구하여 유한요소법과 비교하여 제안하는 방법의 유용성을 검증하고 고차모드의 영향을 조사하였다.

• The Korean Journal of Archival Studies
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• no.61
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• pp.119-156
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• 2019

The records centers service of public institutions helps efficient work activities of internal users, who actually do the work, and becomes the foundation for strengthening the competitiveness of the institution. Based on QFD technique, one of the quality control techniques, this study was intended to propose a plan to improve the quality of the records center service by analyzing and comparing the quality of the records center service of public institutions. To this end, as a follow-up study of Lee, Su-jin(2018), the research target was expanded to local governments to apply the QFD technique and reconstructed the HoQ based on the results of the expanded QFD application. Moreover, this study suggested measures to improve the quality of service in the records center of public institutions by compiling the implications of comparing the records center service HoQ and prioritizing the technology characteristics of the records center service.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.372-373
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• 2013

• Transactions of the Korean Society of Mechanical Engineers A
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• v.23 no.6 s.165
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• pp.912-921
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• 1999

Shear stress acting on the arterial wall by blood flow is an important hemodynamic factor influencing blocking of blood vessel by thickening of an arterial wall. In order to study the effects of wall elasticity on the wall shear rate distribution in an artery-divergent graft anastomosis, a rigid and a elastic model are manufactured. These models are placed in a pulsatile flow loop, which can generate the desired flow waveform. Flow visualization method using a photochromic dye is used to measure the wall shear rate distribution. The accuracy of measuring technique is verified by comparing the measured wall shear rate in the straight portion of a model with the theoretical solution. Measured wall shear rates depend on the wall elasticity and flow waveform. The mean and maximum shear rate in the elastic model are lower than those in rigid model, and the decreases are more significant near the end of a divergent tube. The reduction of mean and maximum of wall shear rate in an elastic model are up to 17 percent.

• Journal of the Korean Society of Costume
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• v.61 no.10
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• pp.89-103
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• 2011

The purpose of this study is to analyze the effects of dominant brand, the quality variation among brands in the extension product category and the self-construals on consumer's attitude about extension products. The experimental design consist of three-way complex factors and 226 subjects participated for the study. The results showed that when there was fashion brand extension, whether or not there was an existing dominant brand in the extension product category, the quality variation among brands in the extension product category and the types of self-construals had a significant interaction effect on their favorableness and intention to purchase the extension products. Regardless of an existing dominant brand however, the group who had an interdependent self-construal showed higher favorableness and intention to purchase the extension products when the quality variation among brands in the extension product category was lower than when it was high, whereas the group who had an independent self-construal showed no significant difference of the favorableness and intention to purchase the extension products.

• Journal for History of Mathematics
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• v.3 no.1
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• pp.47-70
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• 1986

• Proceedings of Korean Society of Archives and Records Management
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• 2016.10a
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• pp.95-98
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• 2016