• 한국안전학회지
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• 제20권3호
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• pp.71-77
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• 2005

This study aims to find the safe vent area to prevent a destruction of building by gas explosion in a building. Explosion vessel which used in this experiment is 1/5 scale down model of simple livingroom and its dimension is 100cm in length 60cm in width and 45cm in height. Liquified petroleum gas(LPG) was injected to the vessel to the concentration of 4.5vol%, and injection rate were varied in 1L/min or 4L/min. Gas mixture was ignited by the 10kV electric spark. For analysis the characteristics of vented explosion pressure according to the vent size and vent shape, its size and shape were varied. From the experiment, it was found that explosion pressure in the vented explosion :in affected by the gas injection rate, vent area and vent shape. And the vent area to volume ratio(S/V) to prevent the building destruction by explosion pressure, it is recommended that the design of vent area happened by the explosion should be above 1/500cm in S/V. And if the vent area has complicate structure in same area, vented explosion pressure will be higher than a single vent, and possibility of building destruction will increase. Therefore to effectively vent the explosion pressure for protect a building and residents from the gas explosion hazards, the same vent area should have a singular and constant shape in the cross-sectional area of the vessel.

• 대한기관식도과학회지
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• 제4권1호
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• pp.85-90
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• 1998

The role of the ECP(Eosinophilic cationic protein) is still unknown in the allergic rhinitis. In bronchial asthma, ECP can induce the exposure of the neuropeptidergic nerve to environments destroying the bronchial mucosa, aggravating the bronchial hypersensitivity and delay the mucociliary clearance. In the clinical aspect, we can (md that patients with perennial allergic rhinitis sometimes have sinusitis. The purpose of this article is to evaluate whether mucosal damage by ECP can play a role to develop the sinusitis by delaying the mucociliary clearance, and relationship between long symptom duration of allergic rhinitis and mucociliary clearance. In 32 perennial allergic rhinitis patients, we elucidated there is correlation among ECP presence, mucociliary clearance, sinusitis, and symptom durations. The obtained results were as follows : 1. ECP appeared in all mucosa of each specimen. 2. Mean mucociliary clearance time is 6 mins. 12 sec. in allergic patients with sinusitis, 6 mins. 36 sec in allergic patients without sinusitis. 3. n out of 32 cases have mucosal destruction. 4. Symptom duration is not correlated with the development of sinusitis. This study suggests that ECP may destroy the mucosa in allergic rhinitis and the mucociliary clearance of allergic rhinitis is not related to sinusitis and symptom dotation. Therefore development of sinusitis in allergic rhinitis seems not to be caused by delaying of mucociliary clearance due to mucosal destruction, but by some other factors.

• 한국식품영양학회지
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• 제34권1호
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• pp.26-35
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• 2021

Myrosinases (thioglucosidases) catalyze the hydrolysis of a class of compounds called glucosinolates, of which the aglycones show various biological functions. It is often necessary to minimize the loss of myrosinase activity during thermal processing of cruciferous vegetables. Myrosinase was isolated from a popular spice, white mustard (Sinapis alba), and its thermal inactivation kinetics was investigated. The enzyme was extracted from white mustard seeds and purified by a sequential processes of ammonium sulfate fractionation, Concanavalin A-Sepharose column chromatography, and gel permeation chromatography. At least three isozymes were revealed by Concanavalin A-Sepharose column chromatography. The purity of the major myrosinase was examined by native polyacrylamide gel electrophoresis and on-gel activity staining with methyl red. The molecular weight of the major enzyme was estimated to be 171 kDa. When the consecutive step model was used for the thermal inactivation of the major myrosinase, its inactivation energy was 44.388 kJ/mol for the early stage of destruction and 32.019 kJ/mol for the late stage of destruction. When the distinct two enzymes model was used, the inactivation energy was 77.772 kJ/mol for the labile enzyme and 95.145 kJ/mol for the stable enzyme. The thermal inactivation energies lie within energy range causing nutrient destruction on heating.

• Advances in aircraft and spacecraft science
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• 제9권1호
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• pp.59-68
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• 2022

The physical and mathematical foundations of the heat-shielding composite materials functioning under the conditions of aerodynamic heating of aircraft, as well as under the conditions of the point effect of high-energy radiation are considered. The problem of deformation of a thin shallow shell under the action of a local temperature field is approximately solved. Such problems arise, for example, in the case of local destruction of heat-protective coatings of aircraft shells. Then the aerodynamic heating acts directly on the load-bearing shell of the structure. Its destruction inevitably leads to the death of the entire aircraft. A methodology has been developed for the numerical solution of the entire complex problem on the basis of economical absolutely stable numerical methods. Multiple results of numerical simulation of the thermal state of the locally heated shallow shell under conditions of its thermal destruction at high temperatures have been obtained.

• 한국추진공학회지
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• 제27권1호
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• pp.9-16
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• 2023

본 연구에서는 고체추진기관 내 연소관단열재의 열분해와 삭마를 고려하여 단열재의 열응답을 예측할 수 있는 일차원 해석기법을 개발하였다. 모델링에는 연소관단열재 내부에서 발생하는 열분해로 인한 물성변화, 숯층의 팽창 및 분해가스 이동을 고려하였다. 또한 연소가스로부터의 복사/대류 열유속을 경계조건으로 적용하였으며 단열재 표면에서 발생하는 화학적 삭마속도를 대수식으로 모델링하였다. 해석기법 검증을 위해 열전대가 설치된 시험모터에 대한 해석을 수행하였다. 해석으로 도출된 온도분포는 시험과 유사한 값을 나타냈으며 시험과 예측 열파괴두께의 오차는 0.1 mm 내외였다.

• Tuberculosis and Respiratory Diseases
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• 제39권4호
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• pp.343-347
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• 1992

연구배경 : 한쪽폐의 전체가 파괴되는 경우는 여러 원인이 있을 수 있다. 이중에서 폐결핵으로 인하여 만성적 염증과 섬유화등을 통하여 파괴된 경우 그 좌우 발생빈도에 차이가 있음을 보고 최근 4년간 국립 공주 결핵뱅원 흉부내과에 입원하였던 224명의 환자를 대상으로 하여 조사하였다. 방법 : 입원 당시의 흉부 방사선 소견을 4가지로 분류하고 성별, 연령, 질병기간, 세균학적 검사를 조사하였다. 결과 : 1) 남녀비는 2 : 1이고 연령은 31~40세가 67명 (30%)으로 가장 많았다. 2) 질병기간은 대부분(88%)이 3년 이상 장기간의 병력을 가지고 있었으며, 6~10년 사이가 87명(39%)로 가장 많았다. 3) 객담 검사상 대부분(80%)이 양성이었다. 4) 흉부 방사선 소견상 좌측폐 전체가 파괴되고 우측에 부분적 병변을 가진 경우가 181명(81%)으로 가장 많았으며 우측폐 전체가 파괴되고 좌측에 부분적인 병변을 가진 경우 31명(14%), 좌측 전폐 파괴만 있는 경우 11명(5%) 그리고 우측 전폐 파괴만 있는 경우 1명 이었다. 5) 성별, 연령, 질병기간 그리고 객담 검사와 흉부 방사선 소견 사이에는 뚜렷한 차이점을 발견할 수 없었다. 결론 : 본 조사결과 폐결핵 환자에서 한쪽폐의 전체가 파괴되는 경우 주로 좌측임을 알게 되었다. 이는 폐결핵 자체의 직접전파, 폐결핵 합병증과 그에 따른 2차적 변화, 기관지 결핵 등에 있어서 좌측폐의 파괴가 더 용이하기 때문으로 생각된다. 질병 기간에 따른 소견 및 질병 초기부터의 변화과정에 대하여 더 많은 연구가 필요 하라라 사료된다.

• Journal of Korean Neurosurgical Society
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• 제47권1호
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• pp.11-16
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• 2010

Objective: Abnormalities of the bone are frequently encountered in patients with meningioma, and hyperostosis and endostosis are common bone alterations in these tumors. Extensive bony destruction is very unusual in patients with meningioma. We report six cases of intracranial meningioma associated with an osteolytic lesion of the skull and discuss the underlying mechanisms that may be responsible for bone destruction in patients with meningioma. Methods: Six patients were classified into three groups, severe, moderate and mild, according to the degree of osteolytic bony destruction. The tumor was classified as intracranial or extracranial, depending on its location. We investigated the potential role of matrix metalloproteinase (MMP) in meningioma-associated osteolysis. The levels of MMP expression were determined by gelatin zymography, reverse transcription-quantitative PCR analysis (RT-PCR) and immunohistochemical analysis. Results: Complete surgical removal of the lesion was performed in each patient. Histological examination revealed benign meningioma in four cases, and two cases of atypical meningioma. Patients did not have a poor prognosis except one case of recurred atypical meningioma. Gelatin zymography and RT-PCR detected high levels of MMP-2 in almost all extracranial masses in comparison with the intracranial masses and MMP9 in two. There was no difference in the severity of bone destruction. Immunohistochemical analysis revealed MMP-2 expression in the vicinity of the bone destruction, and a few MMP-9-positive stainings were observed. Conclusion: Osteolysis of the skull in patients with meningiomas might not be indicative of malignant pathological features and poor prognosis. Invasion to the extracranial portion and osteolysis might be associated with MMP-2 expression in meningioma.

• 전기화학회지
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• 제2권4호
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• pp.183-189
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• 1999

원자력 시설의 가동 및 유지보수 중에 중$\cdot$저준위 방사성폐기물로 다량 생성되는 폐 유기이온교환수지를 상온의 수용 상 내에서 분해 처리하는 공정을 개발할 목적으로, 전기화학적으로 생성되는 Ag(II)를 매개산화제로 사용하여 양이온 및 음이온교환수지의 분해 연구를 수행하였다. Ag(II) 매개산화 공정에서 제어 가능한 인자인 전류, 온도 및 전해질 농도가 이온교환수지의 분해거동에 미치는 영향을 고찰하였다. 양이온교환수지는 거의 대부분 $CO_2$로 분해되었으며, 전류밀도가 감소할수록 전류효율이 증가됨을 보인 반면에 양극전해질로 사용된 질산의 농도 및 온도가 증가하더라도 분해거동에는 영향을 미치지 않았다. 양이온교환수지와는 달리 음이온교환수지의 분해시에는 온도와 무관하게 약 $10\%$ 정도가 CO로 분해되었고, $CO_2$로의 분해효율은 온도에 의존하는 경향을 보였으며, $60^{\circ}C$ 이상에서 효과적으로 분해가 가능하였다.

• 대순사상논총
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• 제20권
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• pp.169-191
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• 2009

The Four Tenets of Daesoon thought are the Creative conjunction of the virtues of Eum and Yang, the Harmonious union of divine beings and human beings, the Resolution of grievances for the mutual beneficence of all life and the Realization of the Dao in the world. This article compares the concepts of the "Creative conjunction of the virtues of Eum and Yang", the "Harmonious union of divine beings and human beings" and the "Resolution of grievances for the mutual beneficence of all life" with "EumYangDaeDaeRon", "ShinMyonKiDeok", the Theory of Mutual Giving Life / Mutual Destruction (SangSaeng/SangGeukRon) of the Book of Changes and analyzes their common and different points. The conclusion is that Daesoon thought and the philosophy of the Book of Changes share common fundamental standpoints. However, the Daesoon thought defines the world of SeonCheon (the state before the Heaven and Earth have been created) as Mutual Giving Life (SangSaeng), and the world of HuCheon (the state after the Heaven and Earth have been created) as Mutual Destruction (SangGeuk). According to Daesoon thought the Mutual Destruction (SangGeuk) is seen as negative, while according to the philosophy of the Book of Changes the Theory of Mutual Giving Live/Mutual Destruction (SangSaeng/SangGeukRon) is viewed as a positive relationship of EumYangDaeDae. This is a point of difference between the Daesoon thought and the philosophy of the Book of Changes. According to EumYangDaeDae relationship theory the contradictory "other" is viewed not as an enemy, but as a necessary element that assures one's existence. When Buddhism and Christianity first came to existence, they did not belong to a main stream. Later, through continuous theorization and systematization they became generally accepted religions. The case of Confucianism was not much different. During Song dynasty in China Buddhism has contributed to the systematization and establishment of Neo-Confucianism; in the middle of 20th century the Confucian scholars of Hong Kong and Taiwan interpreted and defined Confucianism a new in the light of Western philosophy. Thus the "Modern Neo-Confucianism" came to existence. That's why the history of Confucianism is also called "the history of advancing and developing a concept". From this point of view the critical acceptance of some elements of Confucian, Buddhist, Taoist etc. traditions, as well as modern philosophy, by Daesoon, in order to achieve the systematization of Daesoon thought, is a very important process. As a part of this process, this essay explains the Daesoon thought from the point of view of the Book of Changes, which may be said to present the original East-Asian view of the world. Daesoon's emphasis of human dignity, the equality of sexes, the critics the hierarchical society etc. are rather "modern" and should be examined from the point of view of social science. Besides, leaving the boundaries of "modern philosophy", the concepts of "Harmonious union of divine beings and human beings", viewing the universe as one organism etc. should be approached from the point of view of Post-Modernism.

• Advances in Traditional Medicine
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• 제5권4호
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• pp.251-261
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• 2005

Rheumatoid arthritis (RA) is an autoimmune/inflammatory disorder with a complex genetic component. RA is characterized by chronic inflammation of the synovial membrane in the joint, which leads to the progressive destruction of articular cartilage, ligament and bone. Several cytokines such as tumor necrosis $factor-{\alpha}\;TNF-{\alpha}\;and\;interleukin-1{\beta}\;(IL-1{\beta})$ and interleukin-6 (IL-6) have been implicated in the pathological mechanisms of synovial tissue proliferation, joint destruction and programmed cell death in rheumatoid joint. Genome wide screening of subjects suffering from autoimmune diseases especially arthritis revealed linkage to inflammatory molecules like $TNF-{\alpha},\;IL-1{\beta}$ and IL-6, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor-kappaB $(NF-{\kappa}B)$ and human leucocyte antigen/major histocompatibility complex (HLA/MHC) locus. The status of the pharmacological mechanism of herbal drugs in the light of genome wide screening results has been discussed to reinforce the therapeutic potential and the pharmacological basis of the herbal drugs.