• 천문학회지
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• 제17권2호
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• pp.115-125
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• 1984

Effect of magnetic field on the thermal instability is studied in the radiatively cooling region behind an interstellar shock of moderate propagation velocity (${\sim}10\;km/sec$). It is shown that the presence of interstellar magnetic field of a few micro gauss is very effective in preventing the thermal instability from building-up density concentration. In the absence of magnetic field, the shock-induced thermal instability amplifies preshock density inhomogeneity by more than an order of magnitude. However, in the presence of magnetic field, the amplified density contrast is shown to be only a factor 2.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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• pp.287-288
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• 2012

DNS is performed to examine the propagation characteristics of stagnating turbulent premixed flames. Results show good agreement with the recently proposed relationship for turbulent burning velocity, $S_T$. It is shown that $S_T$ increases through a thinner flamelet, turbulence production and correlation between fluctuating velocity and buoyancy force respectively for diffusive-thermal, hydrodynamic and Rayleigh-Taylor instability. The mean curvature doesn't have significant effect on $S_T$ at the leading edge.

• Communications for Statistical Applications and Methods
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• 제13권1호
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• pp.167-175
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• 2006

It has long been recognized that cancer is a genetic disease. To find this measures of genetic instability, stain cells with chromosome specific probes using chromosome in-situ hybridization technique is adopted. Even though in-situ hybridization technique is powerful, truncation of nuclei often results in under-representation of chromosome copies in slides due to the sectioning of tissue blocks. Because of this problem we suggest three different methods to analyze the cervical cancer data set. We observe that genetic instability is an increasing function of histology and our suggested model is the best in detecting genetic instability of tumorigenesis processes.

• 대한기계학회논문집
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• 제18권11호
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• pp.3032-3038
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• 1994

The paper discusses a combustion instability phenomena encountered in recent solid rocket motor development efforts at ADD(Agency for Defense Development). It has happened to occur as an irregular burning in development of smokeless propellant rocket motor. Through investigating the spectral analysis of accelerometer and strain gage signals which are recorded in static firing tests and acoustic modal analysis of motor inside cavity with ANSYS, the instability is found to be the second tangential mode.

• Archives of Pharmacal Research
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• 제18권1호
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• pp.31-37
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• 1995

S. pneumoniae (pneumococcus) gene cloning and library construction in E. coli multicopy plasmid has been hampered, in part, by instability problems. In this study, stability of pneumococcus gene library in cosmid vector and pACYC184 was examined. Pneumococcus library in the cosmid vector pHC79 was extermely unstable that most of the recobinant clones were degenerated rapidly. Only 2 out 849 clones were stable and had appropriate insert size. Pneumococcus library in pACYC184 was also so unstable that the pneumococcal inserg and/or part of the vector were deleted. However, the instability problems seemed to be resolved when transcription teminator plasmid was employed for pneumococcus library construction.

• 대한기계학회논문집
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• 제15권6호
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• pp.1948-1966
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• 1991

본 연구에서는 2상 횡유동을 받는 튜브군의 진동 메카니즘을 규명하기 위한 실험계획의 일환으로 실시된 실험으로부터 튜브군의 유체탄성 불안정성 상수에 관해 고찰하였다. 실험은 먼저 p/d=1.47 및 1.32 튜브군에 대해 수행되었는데, 이들 튜브 군의 결과는 참고문헌에 발표하였다. 본 논문은 후속 실험으로 수행된 p/d=1.22인 튜브군을 사용하여 유체탄성 불안정성 상수를 고찰한 참고문헌의 후속논문이다. 실 험은 액체상태로 부터 99% 보이드율(void fraction)까지 변화된 2상 유동에서 튜브가 유체탄성 불안정성 상태에 도달할 때까지 점진적으로 증가하였다.실험결과는 p/d= 1.32 alc 1.47 튜브군의 유체탄성 불안정성 결과들과 종합. 비교되었다.

• 대한족부족관절학회지
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• 제14권2호
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• pp.119-122
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• 2010

Purpose: One of the main contributors to proximal fifth metatarsal fracture is ankle inversion and the incidence of recurrence may increase in patients with ankle instability. So, the authors confirmed the patients of proximal fifth metatarsal fracture with ankle instability by checking the history and magnetic resonance imaging (MRI) and assessed the value of MRI as therapeutic prognosis and clinical indicators for prevention of recurrence. Materials and Methods: Patients with proximal fifth metatarsal fractures visited our hospital during recent five years were reviewed. 35 patients with suspected damage by ankle inversion had been identified a history of ankle instability and checked the hindfoot malalignment through hindfoot alignment view and MRI was performed prospectively. The patients was devided to three groups on the location of fracture site and the groups were compared each other. Results: The mean time from injury to checking MRI was 10.7 days. There was no structural abnormality and was no significant difference according to the location of fracture. The patients with history of ankle inversion were 31(88.6%) and the patients with history of chronic or recurrent injury were 22 patients (62.9%). The lesion of MRI related to lateral ankle instability were identified in all patients. Conclusion: This study noted a high incidence of lateral ankle instability that was identified by MRI in the patients of proximal fifth metatarsal fracture. Aggressive treatment for lateral ankle instability should be needed for complications as proximal fifth metatarsal fracture to reduce the recurrence and occurrence.

• The Journal of Korean Physical Therapy
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• 제23권4호
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• pp.15-22
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• 2011

Purpose: The purpose of this study was to investigate the relationship between hip abductor muscle strength and lumbar instability in patients with chronic low back pain. Methods: Fifty-two female patients were recruited for this study. The patients' history was recorded and was used to determine the general characteristics of the female complaints. The women were additionally examined to determine whether the level of pain was characteristic of patients with chronic lumbar instability. The following tests were also carried out in the subjects during the examination: 1) the prone instability test. 2) the test for aberrant movement patterns during lumbar flexion test. 3) the straight leg raising test. 4) posterior-to-anterior mobility test, and 5) the test for age and strength of the hip abductor muscle following assessment of the dominant side. In particular, hip abductor muscle strength was evaluated using a dynamometer. Results: The test results showed that the number of positive responses for the five types of lumbar instability tests performed, was significantly related to the strength of the hip abductor muscle. The average hip abductor muscle strength in total subjects was $72.89{\pm}7.66N$, whereas the average hip abductor muscle strength in subjects who showed positive responses to more than four out of the five tests, was $44.70{\pm}5.79N$. Conclusion: The results demonstrated that the hip abductor muscle strength and lumbar instability were negatively correlated. The lower was the strength of the hip abductor muscle, the higher was the possibility of lumbar instability.

• 대한기계학회논문집A
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• 제35권10호
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• pp.1205-1210
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• 2011

척추 불안정성은 요통과 관련되어 있다고 알려져 있다. 하지만 척추 불안정성과 관련된 임상적 연구가 충분하지 않아서 불안정성의 정의가 정량적으로 확립되어 있지 않다. 또한 추간판 퇴행 및 손상, 인대 결손, 협부 결손 등이 불안정성을 발생시키는 요인으로 알려져 있으나, 척추 불안정성에 미치는 영향이 명확하게 분석되어 있지 않다. 본 연구에서는 요추 단분절의 3 차원 유한요소 모델을 이용하여 인대 결손과 협부 결손이 단독 또는 복합적으로 척추 불안정성에 미치는 영향을 정량적으로 분석하였다. 여기서 굽힘 및 신전 시 척추의 시상각과 전위거리가 척추 불안정성을 나타내는 지표라고 가정하였다. 본 연구의 결과는 척추 불안정성의 원인과 기전을 이해하는데 도움이 될 수 있을 것이다.

• Clinics in Shoulder and Elbow
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• 제19권3호
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• pp.155-162
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• 2016

Background: The study aimed to determine the type of capsular insertion and the extent of capsular elongation in anterior shoulder instability by quantitatively evaluating their computed tomography arthrographic (CTA) findings, and to investigate the correlation of these parameters with surgical outcomes. Methods: We retrospectively reviewed 71 patients who underwent CTA and arthroscopic capsulolabral reconstruction for anterior shoulder instability between April 2004 and August 2008. The control group comprised 72 patients diagnosed as isolated type II superior labrum anterior to posterior (SLAP) lesion during the period. Among the 143 patients, 71 were examined with follow-up CTA at an average 13.8 months after surgery. It was measured the capsular length and cross-sectional area at two distinct capsular regions: the 4 and 5 o'clock position of the capsule. Results: With regards to the incidence of the type of anterior capsular insertion, type I was more common in the control group, whereas type III more common than in the instability group. Anterior capsular length and cross-sectional area were significantly greater in the instability group than in the control group. Among patients of the instability group, the number of dislocations and the presence of anterior labroligamentous periosteal sleeve avulsion lesion were significantly associated with anterior capsular redundancy. Postoperatively, recurrence was found in 3 patients (4.2%) and their postoperative capsular length and cross-sectional area were greater than those of patients without recurrence. Conclusions: Capsular insertion type and capsular redundancy derived through CTA may serve as important parameters for the management of anterior shoulder instability.