• The Journal of the Acoustical Society of Korea
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• v.31 no.1
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• pp.19-28
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• 2012

The time-domain solution from the Kirchhoff integral equation for an exterior problem is not unique at certain eigen-frequencies associated with the fictitious internal modes as happening in frequency-domain analysis. One of the solution methods is the CHIEF (Combined Helmholtz Integral Equation Formulation) approach, which is based on employing additional zero-pressure constraints at some interior points inside the body. Although this method has been widely used in frequency-domain boundary element method due to its simplicity, it was not used in time-domain analysis. In this work, the CHIEF approach is formulated appropriately for time-domain acoustic boundary element method by constraining the unknown surface pressure distribution at the current time, which was obtained by setting the pressure at the interior point to be zero considering the shortest retarded time between boundary nodes and interior point. Sound radiation of a pulsating sphere was used as a test example. By applying the CHIEF method, the low-order fictitious modes could be damped down satisfactorily, thus solving the non-uniqueness problem. However, it was observed that the instability due to high-order fictitious modes, which were beyond the effective frequency, was increased.

• Korean Security Journal
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• no.33
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• pp.229-260
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• 2012

The purpose of this study is to categorize the past Chiefs of Presidenteal Security Service so far based on their level of expertise and authority so that we can identify some specific reasons as to why some of them are recognized as successful while others are not, and that the categorization will be a guideline to future successful administration. In order to do so, a quantitative research has been implemented through meetings of a group security science expert who has been in security business for substantial amount of time. The result is as following: Authoritative/professional: 2nd Chief of P.S.S. Park, Jong-Gyu, 5th Chief of P.S.S. Jang, Se-Dong, 7th Chief of P.S.S. Lee, Hyeon-Wu, 8th Chief of P.S.S. Choi, Seok-Rip. Authoritative/Non-professional: 1st Chief of P.S.S. Hong, Jong-cheol, 3rd Chief of P.S.S. Cha, Ji-cheol, 6th Chief of P.S.S. Ahn, Hyeon-Tae, 14th Chief of P.S.S. Kim, In-Jong. Non-authoritative/professional: 4th Chief of P.S.S. Jeong, Dong-Ho, 9th Chief of P.S.S. Park, Sang-Beom, 13th Chief of P.S.S. Yom. Sang-Guk. Non-authoritative/Non-professional: 10th Chief of P.S.S. Kim, Gwang-Seok, 11th Chief of P.S.S. Ahn, Ju-Seop, 12th Chief of P.S.S. Kim, Se-Ok. This categorization research on the Chief of P.S.S. suggests that any president, to be a successful one, must choose the Chief of P.S.S. based on his/her expertise in order to secure national security.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2328-2333
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• 2010

A direct boundary element method(DBEM) is widely applied for various acoustic wave problems. But this method has numerically non-unique solutions around the eigenfrequencies of the interior Dirichlet problem for the region enveloped with the acoustic boundary. A CHIEF method had been generally adopted to resolve the non-uniqueness problem and a new technique called ICA-Ring method has been suggested recently. In this paper, the characteristics of two techniques for avoiding the non-uniqueness of DBEM are examined and numerical codes embodying both techniques are developed. Numerical calculations are also carried out for an uniformly pulsating sphere, of which the results are investigated by including the comparisons with theoretical solutions.

• Journal of Digital Convergence
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• v.10 no.10
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• pp.347-352
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• 2012

As medical treatment is developing with technology, the men's average life expectancy is extended. Therefore, primary medical care becomes emphasized in order to reduce the medical expenses in the long term by satisfying individual's life being healthy. The date for this thesis was collected from January 2011 to June 2011. 889 patients who visited the university hospital emergency room and hospitalized in internal medicine, were picked as the research subjects and they were targeted to be recorded the distribution of chief complaint and principal diagnosis of the patients. Also, this record was used to apply to the standard Classification of Diseases(as known as ICD) and the method of detailed classification of the primary medical care(as known as ICPC) to compare each other. In order to analysis, frequency analysis was used to see vital statistics and the cross tabulations were used to see the distribution of chief complaint according to ICD and ICPC. Results of the research were Abdominal pain(17.7%), Dyspnea(13.5%), Fever (12.5%), and Haematemesis (9.8%), and those symptoms represented the 54.5% of overall chief complaints that is treated in primary care. Therefore, it is acceptable to use the classification of the primary medical care at doc-in-a-box. Also, in case of diagnosis of abdominal pain, it is classified to R10 in ICD and 116 patients(18.7%) belonged to it, but according to ICPC, it is subdivided to Epigastric(11.5%) and General(5.8%). ICPC classification, which is focused to primary medical care is more detailed than ICD classification. Because the data that is collected for this thesis is from only one hospital, it is hard to represent to all the cases, but ICPC in emergency medical care, it has more classification available and it can subdivide the patients effectively, so it is meaningful.

• Applied Microscopy
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• v.35 no.3
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• pp.153-163
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• 2005

This experiment was performed to evaluate the morphological responses of the gastric chief cells of the mouse, inoculated with Ehrlich carcinoma cells in the inguinal area, following administration of BCG (Bacillus Calmette-Guerin). Healthy adult ICR mice weighing 25 gm each were divided into normal and experimental groups (experimental control group and BCG treated group). In the experimental groups, each mouse was inoculated with $1x10^7$ Ehrlich carcinoma cells subcutaneously in the inguinal area. From next day after inoculations, 0.2 mL of saline or BCG (0.5 mL/25 g B.W.: $0.03{\times}10^8{\sim}0.32{\times}10^8$ CFU) were injected subcutaneously to the animals every other day, respectively. The day following the last injection, each mouse was sacrificed. Pieces of the tissue were taken from the stomach, prefixed with 2.5% glutaraldehyde-1.5% paraformaldehyde solution, followed by post-fixation with 1% osmium tetroxide solution. The ultrathin sections were stained with uranyl acetate and lead citrate. The size of zymogen granule and the size of the mitochondrion of the gastric chief cells were observed and calculated. In the BCG treated group, most chief cells did not show any difference in ultrastructure, except that myelin figures were more frequently observed, in comparison with that of nornmal control group. The size of zymogen granule in the gastric chief cells of normal control, experimental control and BCG-treated groups were $0.98({\pm}0.108){\mu}m,\;1.05({\pm}0.092){\mu}m\;and\;0.93({\pm}0.053){\mu}m$, respectively. And the mitochondrial size of the gastric chief cells of normal control, experimental control and BCG-treated groups were $0.80({\pm}0.130){\mu}m,\;0.83({\pm}0.143){\mu}m\;and\;0.72({\pm}0.078){\mu}m$, respectively. From the above results, it was concluded that BCG may slightly suppress function of the gastric chief cells.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.4
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• pp.253-268
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• 1993

The author studied on the 109 cases of ameloblastoma which had been diagnosed with biopsy during the period of 1962 to 1992 at the Kyungpook National University Hospital, Kyemyung University Hospital, Youngnam University Hospital, Catholic Medical School Hospital, Pusan National University and Maryknoll Hospital. This study contains the statistical analysis of the treatment method according to the clinicopathological findings such as sex, age, location, chief complaints, duration, radiographic findings, size and recurrence. The results were as follows : 1. The incidence rate was 59.7% in male and 40.3% in female. 2. At the time of diagnosis, the age of the patients ranged from 9 to 69 years(average 31.4years). The cases of 72.4% were in the 2nd, 3rd, and 4th decades of life. 3. The majority of cases occurred in the mandible 88.9%, especially in the mandiblar angle area 57.8%. 4. The most prevalent chief complaints was swelling 58.7%. 5. As regards duration, the cases less than 1 year appeared 49.5% and average duration is 31.34months. 6. Unilocular type showed 43.1% and multilocular type appeared 56.9%. 7. Conservative treatment was performed 39.4% and radical treatment was employed 60.6%. 8. There were variations of lesional sizes between 2.0cm and 15cm(average 6.26cm). 9. The recurrence rate is 29.4%. 10. The frequency of treatment was not in association with sexes, locations, chief complaints and sizes. 11. Radical treatment was performed more frequently in cases of older age group(above 20 years old), multilocular cases, above average duration(31.34 months) group and recurrent cases (P<0.05).

• Korean Journal of Occupational Health Nursing
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• v.19 no.2
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• pp.140-149
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• 2010

Purpose: The purpose of this study was to explore the coping process of chief Executive Nurses(CENs) Who Had Experienced Unexpected Dismissal.The research question was "would you tell me about your experience of sudden dismissal?" Method: The methodology of collecting and analyzing data used in this study followed the ground theory of Strauss and Corbin (1998). Data were collected through in-depth interviews with open-ended questions about the subjects' coping experiences, which were audio-taped and transcribed. The survey was conducted between April and May, 2007. The subjects of this study were 5 CENs. Result: The results of the study are as follows. Core category of This Study was "Battling unsupported against the overwhelming reality." The participants had to face the most unexpected reality of being laid off. Their emotional/psychological response were betrayal, powerlessness, lonesomeness, sorrow, and hopelessness. They felt like a general who is facing overwhelming enemy in a war. The coping process was found to have four stages: shocked stage, resisting stage, negotiating stage and reflecting and transcending stage. Conclusion: The result of this study suggested that ceaseless exertion and cooperation at organizational and individual levels are needed to establish stable status and power of nursing departments and CENs in hospitals.

• Journal of the Korean Geotechnical Society
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• v.16 no.3
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• pp.47-55
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• 2000

본 연구에서는, 유전자 알고리즘을 이용한 piled raft 기초의 최적설계 기법을 제시하였다. 최적설계에 사용한 목적함수는 구조물의 사용한계에 해당하는 부등침하량과 piled raft 기초의 시고비용 차원에서의 말뚝과 raft의 총 중량으로 하였다. 유전자 알고리즘은 다읜의 적자생존의 법칙을 따르는 자연진화 법칙을 바탕으로 한 최적화 기법이다. 본 연구에서는 piled raft 기초의 해석방법으로 Clancy(1993)가 제시한 "hybrid" 해석방법을 사용하였으며, 유전자 알고리즘기법은 Goldberg(1989)가 제시한 단순 유전자 알고리즘(SGA)을 적용하였다. 또한 유전자 알고리즘을 이용한 최적설계기법의 유효성을 평가하기 위해 설계예제 및 매개변수변화연구를 통해 piled raft 기초시스템의 중요 설계인자들에 대한 분석을 수행하였다. 매개변수변화연구로부터 말뚝의 길이와 raft의 두께가 증가할수록 piled raft 기초시스템의 전체 중량은 일정한 값에 점차적으로 수렴하였으며, 지반의 강정, raft의 두께 말뚝의 길이 및 강성이 증가할수록 말뚝의 최적위치는 raft의 중앙에 집중되는 경향으로 나타났다.경향으로 나타났다.

• The Journal of the Acoustical Society of Korea
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• v.12 no.4
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• pp.21-31
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• 1993

불규칙한 기하구조 및 기하학적 특이점들을 갖는 방사체에 의해 형성되는 음장을 예측하는 작업은 매우 어려운 일이다. 이러한 종류의 문제를 해결하기 위하여는 Seybert에 의해 제창된 내, 외부를 연성하여 해석하는 경계요소법에 의한 해석이 유용하다고 여겨지고 있다. 본 연구에서는 연성경계요소법을 재 구성하여 예제로서 얇은 벽면을 갖는 개방된 관에서 방사되는 음장을 선택한 후, 이 방법의 신뢰성, 적용성 및 오차에 대한 해석을 해?ㄴ다. 외부 방사 문제에 있어서의 비유일성문제는 소외 CHIEF 기법을 도입하여 해결하였다. 두 개의 마이크로폰을 사용하여 신호처리를 통한 실험 결과와 본 경계요소법에 의한 결과는 서로 잘 일치하였다. 한편 경계면에 몹시 가까운 지점에서의 음장을 예측할 때의 오차 해석을 수행한 결과, 예측 오차가 10% 이내에서 유지되려면 경계요소법의 가장 짧은 변의 길이가 예측점과 벽면 사이의 거리보다 최소한 10배 이상은 커야함을 알아내었다. 이 기법은 기하학적인 특이점을 포함하는 각종 음향 문제에 매우 유효 적절한 방법으로 생각된다.

• Korean Journal of Heritage: History & Science
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• v.46 no.2
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• pp.166-185
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• 2013

After analyzing the location, arrangement, inner structure, and form of the hunting pit in the Bronze Age, this paper sets up three types and talks about types of hunting pits. After analyzing the types of the hunting pit, three types of hunting pits are derived: mountain district - large group's arrangement - long oval - I II type(A), mountain district - arrangement in a line - oval - I type(B), flat area - arrangement in a line - oval - I III type(C). Literature, the ways in hunting pits, the purpose of the installations, and the characters are studied and compared with those of the anthropological cases. Even though hunting pits of types A and B are constructed to hide and get protein and bone of animals for breeding, there are differences in the ways in hunting and characters. Type of A seems to be constructed only for occupation that is the standardized hunting method on a small works. However, type B is the chasing method to hunt as a group and it has various purposes including main occupation. For example, it is for improving the war skills by practicing the hunting strategies and cooperating with the people. In addition, it is for getting a sacrifice for god. The type C hunting pit is estimated that it plays a role to protect themselves from invasion. It's inferred that there are many purposes for military defense and protection of people or animals within the village. It is the reason why the construction is spread in hunting pit including various purposes in the Bronze age that originates in social and economical specialization like the increase in agricultural productivity and appearance of a chief.