로렌츠 다양체상에서 쟈코비안의 비교 정리

양기열,김삼태,김정식 順天大學校 1998 論文集 Vol.17 No.1

본 논문에서는 두 로렌츠 다양체 위에서 자코비안을 정의하고, 각 Ricci 곡률과 평균곡률의 조건이 주어질 때 두 자코비안의 크기를 비교하였으며 이 결과를 이용하여 [9]에서 증명한 Rauch 비교 정리도 간단히 증명 하였다. In this paper, we will define the Jacobian along the unit speed future directed timelike geodesic segment perpendicular to the spacelike submanifold N and present the comparison of Jacobians under assumption on the curvatures such as the extension of the Rauch comparison theorem for timelike geodesics[9].

염색 단판을 이용한 集成 染色 무늬목 開發

안삼근,강형철,안상열,이균필,변희섭 경상대학교 농업생명과학연구원 2002 농업생명과학연구 Vol.36 No.4

본 연구는 집성 염색 무니목 개발을 위하여 사용 가능한 수종과 3종류의 염료를 사용하여 염색시간, 염색온도, 함수율 및 Flitch 제작에 대하여 연구한 결과는 다음과 같다. 실험에 사용한 4수종 중에서 선삭성이 불량한 은수원 사시나무를 제외한 3수종인 소나무와 이태리 포플러, 마티카가 사용 가능한 수종으로 밝혀졌다. Stain은 번지거나 얼룩이 지는 현상, Dylon은 침투 불균일로 부적당하였으나 Fine은 염색상태가 양호하였다. 염색시간은 5시간 이상 되어야 염색정도가 양호하였고, 염색온도는 90℃에서 가장 적당하였으며 생재와 기건재 및 포수재에 대한 영향은 큰 차이가 없었다. Flitch제작에 적당한 함수율은 9%이었다. This study was carried out to develop laminated dyeing wood, for which usable three sixties of trees and 3 kinds of dye stuffs were used to investigate dyeing time, dyeing temperature, moisture content and manufacture of flitch, the results were as follows: Out of four species of trees used in the experiment, it was found that three species, Pinus densiflora, Populus euramercana and Dyrea costulata were usable excluding Populus tomentiglandulosa whose cutting ability was bad. As to influence according to the kind of dye stuff, the Stain of low price could be used as a coloring agent but it was not proper as a dyeing agent due to spreading or staining phenomenon. As Dylon which was generally used to dye textile penetrated them uneven, dyeing only their surface, it was also found improper to be used. On the other hand, the dyed condition was good with Fine. The dyed condition was good when dyeing time was more than 5 hours and it was the most adequate when the temperature was at 90℃. There was no significant difference between their influence on green, dried and saturated wood.-In the manufacture of Flitch, the most appropriate moisture content was 9%.

인천 인현동 호프집 화재 피해자 분석

최정태,안무업,안희철,최영미,정재봉,서정열,유기철,이삼우,박석현,조준휘,김성환,김아진,송근정 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Purpose : This study was conducted to develop field triage, transportation, distribution, and prehospital care at a fire disaster by analyzing the victims of the fore that broke out at a bar in Incheon. Method : We analyzed the cases of the victims of a fire in Incheon in Oct. 1999. We determined the primary care hospital, the arrival time, the burn size, the outcome, and the injury type from the medical records, the concerned organ records, and interviews with concerned persons. Result : The total number of victims was 137: 56 prehospital deaths, 1 hospital death, and 80 survivals. The Pearson correlation coefficient between the burn size and the severity was -0.175. There were 121(89.6%) cases of inhalation injury, 59 (43.7%) cases of flame burns, 66 (48.9%) cases of hypoxic brain damage, and 16 (11.9%) cases involving other types of injury. Conclusion : The causes of death of the fire victims were inhalation injury and hypoxic brain damage due to CO poisoning and other toxic inhalants. We propose the use of a simple triage and rapid treatment(START) system and a reassessment the delayed category in fire disasters.

허혈 및 재관류후 흰쥐 앞정강근과 가자미근에서 나타나는 미세구조와 SOD 활성의 변화

백두진,안동춘,황규성,김혜주,박철홍,정호삼,조근열 대한체질인류학회 1999 해부·생물인류학 (Anat Biol Anthropol) Vol.12 No.2

에너지 획득방법, 당원의 분포, 모세혈관의 분포 및 미세구조의 차이가 나는 백색근육섬유와 적색근육섬유에서 허혈시간에 따라 나타나는 미세구조의 변화와 SOD의 활성변동을 비교 관찰하여 다음과 같은 결과를 얻었다. 1. 앞정강근에서는 2시간 허혈시 사립체에서 바탕질의 전자밀도가 감소하고 사립체능선이 팽대하였고, 재관류 24시간 경과시에는 근육원섬유사이의 거리가 멀어지고 근육세포질세망의 수조와 종말수조가 팽대하였으며 재관류 72시간 경과시에는 정상대조군과 유사한 소견이 나타났다. 2. 가자미근에서 2시간 허혈시 사립체에서는 사렵체바탕질의 전자밀도가 감소하였으며, 재관류 24 시간 경과시는 근육세포질세망의 수조가 팽대하였고, 재관류 72시간 경과시에는 정상대조군과 유사하였다. 3. 4시간 및 6시간 허혈시 미세구조의 변화는 허혈시간과 재관류 시간경과에 따라 심해져 앞정강근에서는 사립체에서 바탕질의 전자밀도가 감소하고 사렵체능선은 불분명하고 소용돌이소체가 나타났으며 근육원섬유 용해와 곤육원섬유괴사가 관찰되었다. 가자미근에서는 근육원섬유에서 근육미세섬유의 배열과 끝가로막이 불규칙해지고 근육세포질세망의 수조가 팽대하였으며 근육원섬유용해가 나타났다. 4. 앞정강근에서 Cu, Zn-및 Mn-SOD 활성은 미약한 흑은 약한 양성반응을 나타내었고, 가자미근에서는 Cu, Zn-SOD는 미약한 양성반응을, Mn-SOD 는 미약한 혹은 약한 양성반응을 나타내었다. 허혈후 Cu, Zn- 및 Mn-SOD 의 활성은 허혈시간이 길수록 더욱 증가하였다. 5. Cu, Zn- 및 Mn-SOD 활성은 2시간 허혈 및 재관류 24 시간 경과시 약간 증가하였으며 72시간 경과시에는 앞정강근과 가자미근에서 정상대조군과 유사하게 나타났다. 6. 4시간 및 6시간 허혈 및 재관류후 두 근육에서 Cu, Zn- 및 Mn-SOD활성은 증가하였다. 두 근육에서 Mn-SOD의 활성변동은 유사하였으나 Cu, Zn- Mn-SOD의 활성증가는 앞정강근보다 가자미근에서 크게 나타났다. 이상의 결과를 종합하면 허혈 및 재관류 손상은 허혈시간과 재관류시간 경과에 따라 심하게 나타났고 가자미근보다 앞정강근에서 심하게 나타났으며, 손상의 차이는 두 근육에서 나타나는 SOD활성변동과 깊은 연관이 있는 것으로 생각된다. Skeletal muscles are known to have tolerance to ischemia, but a prolonged ischemia can cause damage to muscular tissues. The ischemia-reperfusion injury results from the oxygen free radicals released by leucocytes and formed by the reaction of hypoxanthine and xanthine oxidase. Superoxide dismutase (SOD), one of major antioxidant enzymes occurring in the various tissues of the body metabolizes or scarvanges the oxygen free radicals. Although many studies reported difference in tolerance to ischemia and reperfusion between white and red muscles, some other investigators failed in finding such difference. The present study was performed to examine effects of graded periods of ischemia and reperfusion on the cellular ultrastructure and activity of SOD in white and red muscles. The Sprague-Dawley rats (200~250 g) were used as experimental animals. Under pentobarbita] (50 mg/kg IP) anesthesia, incision was made on lower abdomen and left common iliac artery was occluded by means of a vascular clamp for 2, 4 and 6 hour (hrs). Thereafter, the superficial portion of mid-belly of anterior tibial muscle and soleus muscles were excised at 0, 24 and 72 hrs after onset of reperfusion. The specimens were sectioned into slices, 2 mm in length, 1 mm in width and thickness. Some specimens were prepared for electron microscopic observation and others for determination of SOD activity by using antihuman CU, Zn- and Mn-SOD antibodies. The results obtained were as follows. 1. In anterior tibial muscle, areas with loose electron-density and dilated cristae were observed in the mitochondria immediately after 2 hrs of ischemia, while widened intermyofibrillar spaces and dilated cisternae of sarcoplasmic reticulum were seen after 2 hrs and 24 hrs reperfusion. When subjected to 2 hrs ischemia and 72 hrs reperfusion, no significant change was found in the cellular ultrastructure. 2. In soleus muscle, electron density was loose in the matrix of mitochondria immediately after 2 hrs of ischemia, while cisternae of sarcoplasmic reticulum were dilalated after 2 hrs of ischemia and 24 hrs reperfusion. Following 2 hrs of ischemia and 72 hrs repeifusion, the electron microscopic findings were similar to those of normal rats. 3. The changes in cellular ultrastructure were more prominent in both the 4 hrs and 6 hrs ischemia groups, in which degree of ultrastructural changes were proportional to duration of reperfusion. 4. In anterior tibial muscle, trace or weak immunoreactivities of Cu, Zn- and Mn-SOD were seen, whereas trace immunoreactivity of Cu, Zn-SOD and trace or weak immunoreactivity of Mn-SOD were observed in soleus muscle. 5. The immunoreactivities of CU, Zn- and Mn-SOD were not altered in 2 hrs ischemic and 72 hrs reperfused group, while they were increased slightly in 2 hrs ischemic and 24 hrs reperfused group. 6. In both muscles, the activity of SOD increased following 4 hrs or 6 hrs ischemia and 24 hrs or 72 hrs reperfusion. The changes in immunoreactivity of Mn-SOD were not different between two muscles, whereas immunoreactivity of Cu, Zn-SOD were higher in anterior tibial muscle. Consequently, it is suggested that significant ischemia reperfusion injuries are produced after 4 ~ 6 hrs ishemia followed by 24 hrs or 72 hrs reperfusion, that anterior tibial muscle is more susceptible to ischemic reperfusion injury and that the ischemic-reperfusion injury is closely related with activity of SOD.

Anterior Thigh Pain Following Minimally Invasive Oblique Lateral Interbody Fusion: Multivariate Analysis from a Prospective Case Series

Sam Yeol Chang,Woo Seok Lee,Sujung Mok,Sung Cheol Park,Hyoungmin Kim,Bong-Soon Chang 대한정형외과학회 2022 Clinics in Orthopedic Surgery Vol.14 No.3

Background: Oblique lateral interbody fusion (OLIF) involves the antepsoas approach and psoas major muscle (PMM) retraction to insert the interbody cage orthogonally. Therefore, OLIF is often associated with postoperative anterior thigh pain (ATP) on the approach side. However, there is limited evidence on the nature and risk factors of ATP following OLIF. Methods: Consecutive patients who planned to undergo minimally invasive OLIF and percutaneous pedicle screw instrumentation for lumbar degenerative diseases were prospectively enrolled. The visual analog scale (VAS) for ATP was recorded, and a pain map was drawn daily from the operation day to postoperative day 7 in all patients. We also prospectively collected the preoperative and intraoperative data to identify the risk factors associated with ATP. Radiologically, the total cross-sectional area (CSA), retraction length, and retraction CSA of PMM were measured from the preoperative T2-weighted axial magnetic resonance imaging scans at the L4–5 intervertebral disc level. The patients were stratified into two groups based on the experience of ATP with a VAS score of ≥ 7 at any time point. Additionally, a binary logistic regression analysis was performed to identify the associated factors. Results: The current prospective study included 92 patients (31 men, 61 women) with a mean age of 70.4 years (range, 56–86 years), who underwent OLIF at our institution. The left-side approach was used in 73 patients (79.3%), while 19 (20.7%) underwent a right-side approach. Sixty-five of the total patients (70.6%) experienced approach-side ATP to any extent during postoperative 0–7 days following OLIF. The mean pain VAS (4.4 ± 2.1) and the prevalence (57.6%) were highest at postoperative 2 days. On postoperative day 7, there were 19 patients (20.7%) who complained of residual ATP with a mean VAS of 2.6 ± 1.8. In the multivariate analysis, the PMM retraction length was significantly associated with ATP of VAS ≥ 7 (adjusted odds ratio, 2.316; p = 0.044). Conclusions: In this study, we prospectively collected and analyzed the ATP and associated factors following OLIF and identified the PMM retraction length as a potential independent risk factor for severe ATP in the immediate postoperative period following OLIF.

정전협정 70주년과 한반도 안보

장삼열 ( Sam Yeol Jang ) 한국군사학회 2023 군사논단 Vol.116 No.-

This year marks the 70th anniversary of the Korean War Armistice. At that time, we expected a peace system, but the armistice system has continued until now. Recendy, the security situation around the Korean Peninsula has changed rapidly. Deepening conflict between the U.S. and China, prolonged war in Ukraine, dose ties between Putin and Kim Jong Un, and breaking the war between Israel and Hamas are all negative for stability on the Korean Peninsula. The Korean Peninsula is developing into a more complex situation due to North Korea’s nuclear development and missile provocations. Since the signing of the Armistice Agreement on the Korean Peninsula, the two Koreas and the international community have made efforts to establish peace. However, the North Korea has dug a tunnel and developed nuclear weapons and missiles while having a peaceful dialogue. There have also been 3,121 North Korean provocations. War was suppressed on the Korean Peninsula because of a strong ROK-U.S. alliance, a combined defense system, and the United Nations Command etc. The lessons of the Korean War and the implications of the 70th anniversary of the Armistice Agreement were studied. Looking at the 70th year of the Post Armistice Agreement, I suggested policy alternatives for security on the Korean Peninsula. It is important to strengthen the ROK-U.S. alliance and combined defense posture, revitalize the UNC, gather public opinions, and correctly inform the Korean War.

국제보훈정책의 현주소와 미래 발전방안

장삼열 ( Sam Yeol Jang ) 한국군사학회 2022 군사논단 Vol.109 No.-

Veteran’s policy is a national act that occurs in the interrelationship between the state and the individual people. The promotion and appreciation of the United Nations veterans in Korean War are in return for their dedication and sacrifice in saving Korea from the crisis of the Korean War in the past. I checked the reality of the international veterans’ policy promoted by the Ministry of Patriots and Veterans Affairs and analyzed using SWOT techniques. Strength are the brand value of ROK and proactive veterans policy. Revitalizing veterans diplomacy and building a security soft power are opportunities. On the other hand, the super-aged veterans and COVID-19 are threats. Therefore, it is necessary to develop international veterans’ policies more actively in line with the era of super-aging veterans. I suggested future-oriented development of international veterans’ policies suitable for the COVID-19 era, shift forward veterans’ paradigm and develop customized programs for each country.

The Use of High-Density Pedicle Screw Construct with Direct Vertebral Derotation of the Lowest Instrumented Vertebra in Selective Thoracic Fusion for Adolescent Idiopathic Scoliosis: Comparison of Two Surgical Strategies

Chang Sam Yeol,Kim Jae Hun,Mok Sujung,장봉순,이춘기,Kim Hyoungmin 대한척추외과학회 2023 Asian Spine Journal Vol.17 No.2

Study Design: This study was a retrospective case series.Purpose: This study was designed to determine whether direct vertebral rotation (DVR) of the lowest instrumented vertebra (LIV) using a high-density (HD) construct can reduce fusion segments without increasing adverse outcomes in selective thoracic fusion (STF) for adolescent idiopathic scoliosis (AIS).Overview of Literature: LIV DVR is used to maximize spontaneous lumbar curve correction and reduce adverse outcomes during STF for AIS. However, evidence is limited on whether LIV DVR can allow a proximally located LIV and reduce fusion segments without increasing adverse outcomes.Methods: We reviewed consecutive patients with Lenke 1 AIS who underwent STF from 2000 to 2017. The patients were divided into two groups based on the surgical strategy used: low-density (LD) construct without DVR of the LIV (LD group) versus HD construct with DVR of the LIV (HD group). We collected data on the patient’s demographic characteristics, skeletal maturity, operative data, and measured radiological parameters in the preoperative and final follow-up radiographs. The occurrence of adding-on (AO) and coronal decompensation was also determined.Results: In this study, 72 patients (five males and 67 females) with a mean age of 14.1±2.3 years were included. No significant differences in the demographics, skeletal maturity, and Lenke type distribution were observed between the two groups; however, the follow-up duration was significantly longer in the LD group (64.3±25.7 months vs. 40.7±22.2 months, p <0.001). The HD group had significantly shorter fusion segments (7.1±1.3 vs. 8.5±1.2, p <0.001) and a more proximal LIV level (12.1±0.9 vs. 12.7±1.0, p =0.009). In the radiological measurements, the improvement of LIV+1 rotation (Nash–Moe scale) was significantly larger in the HD group (0.53±0.51 vs. 0.21±0.41, p =0.008). AO and decompensation occurred in 7 (9.7%) and 4 (5.6%) patients in the HD and LD groups, respectively, without any significant difference between the two groups.Conclusions: In this study, the HD group had a significantly shorter fusion level and a more proximal LIV than the LD group; however, the two groups had similar curve correction and adverse radiological outcome rates.

한국의 국제평화활동 30주년 평가와 발전방안

장삼열 ( Sam Yeol Jang ) 한국군사학회 2021 군사논단 Vol.105 No.-

It has been 30 years since the Korean military began international peace operations. This paper analyzed the results and lessons learned of the Korean military's international peace operations over the past 30 years and suggested ways to develop Korea's peace operations. The United Nations is actively engaged in peacekeeping operations for global peace. The UN changed its Force Generation policy and PCRS in 2015 to ensure rapid and dynamic mission performance. Recently, amid the shrinking of international peace operations due to the threat of COVID-19 pandemic, it is developing new concepts and contents of peace operations. The ROK government has sent more than 56,800 troops over the 30 years. The ROK military has established a forbidden tower for peace operations as well as enhancing the status of the country through exemplary UN PKO, Multi-national Forces Peace operations(MNF PO) and Defense Cooperation Activities(DCA). The Korean military has accumulated practical experience, created a model for civil-affairs operations, and achieved extension of diplomatic power. However, there are many things to develop, such as changing the paradigm of the deployment policy, improving organizations related to overseas dispatch, and overhauling related laws. In particular, it is time to prepare for international peace operations in line with the Post COVID-19 era.

학술논문 : 국가 Power-Image를 통해 본 남북한 군사적 갈등 사례 연구

장삼열 ( Sam Yeol Jang ) 한국군사학회 2012 군사논단 Vol.71 No.-

The current study is aimed at preparing the future North Korea policy and the adequate plan based on the political lessons we learned from numerous South-North Korea military conflicts and negotiations. Currently the North is struggling domestically to maintain its hereditary regime, while at the same time suffering from the heavy pressure of international sanctions, primarily from those of the United States. It is more than likely that the North Korea will try another military provocation to the South in an attempt to break through its current political deadlock. The current study analyzed these four cases: The Blue House Raid and the USS Pueblo Incident in 1968, the Axe Murder Incident in Panmunjon on August 18th, 1976, the Rangoon bombing in October, 1983, the Torpedo Attack on the ROK Ship Cheonan in 2010. Analyzed by the DIME+L method, which means approaching the issue by applying the Richard Cottam`s Power-Image Theory in addition to Leadership. The North Korea has been, by participating in non-aggressive negotiations and attempting military provocations at the same time, utilizing both tough and soft strategies for the survival of its regime and a breakthrough for its domestic and foreign deadlock. In the process the South has failed to respond proactive against the North`s military provocations and maintained nothing more than its feeble reactions against them. As a result, the North`s already tough national image has toughened even more, and the South has lost most of its remaining national prestige. The practical strategies and political proposals to regain the South`s distorted national image and effectively counter the North`s future military provocations are needed more than ever. First, it is necessary to strengthen the South`s power-image by preparing a proactive strategy against a possible military provocation by the North Korea and also giving proactive responses in case of the North`s provocation. Second, mid-term and long-term negotiation strategy towards the North should be developed and pushed forward coherently. Third, a close international collaboration system with the international community needs to be pursued. Fourth, as strategy against the DPRK utilizing China as a leverage needs to be developed.