쿰란에센파와 묵시문학

김창선(Chang-Sun Kim) 한국신약학회 2004 신약논단 Vol.11 No.4

주행차량의 공기역학적 주행안전성 평가를 위한 알고리즘 개발연구

김창선(Chang-Sun Kim),김철호(Chul-Ho Kim) 한국자동차공학회 2014 한국자동차공학회 학술대회 및 전시회 Vol.2014 No.11

주행차량의 공기역학적 주행안전성 평가를 위한 알고리즘 개발연구

김창선(Chang-Sun Kim),이승현(Seung-Hyun Lee),김철호(Chul-Ho Kim) 한국자동차공학회 2014 한국자동차공학회 부문종합 학술대회 Vol.2014 No.5

The objectives of vehicle aerodynamic design is on the fuel economy, reduction of the harmful emissions and minimizing vibration and noise and the driving stability of the vehicle. Especially in case of a sedan, aerodynamic driving stability of a vehicle is the main focus, and for this, the proper evaluation of aerodynamic driving stability of a vehicle is required. In this study, we yield the size of moving moment on the body of the vehicle generated by side wind when sedan type vehicle drives on the road and complete a numerical algorithm to evaluate aerodynamic driving stability of a vehicle judging whether such moving moment has a serious impact on vehicle driving stability. The model vehicle for the study is sedan type vehicle shape recommended by SAE. In the study, we yield the pressure drag and the position of C.P. on the body of the vehicle generated when the vehicle drives with side wind using CFD technique. Based on this, we also calculated pitching, rolling and yawing moment of the body of the vehicle generated on the center of gravity, and the result from comparing turning moment values and the size of rotational resistance moment of the body of the vehicle can be used as the basis to judge driving stability such as off-course and rollover of the vehicle. After driving stability of a vehicle when the vehicle drives 100km/h with 15m/s side wind is evaluated using the numerical algorithm drawn from the study, the value of yawing moment is 606N.m, rolling moment -773N.m and pitching moment 84N.m. These values are smaller than each value of rotational resistance moment the model vehicle has, and therefore, the model vehicle’s driving stability is guaranteed when driving 100km/h with 15m/s side wind.

국궁 활쏘기 동작에서의 체중이동과 수행속도, 관절 근력의 관련성

김창선(Chang-Sun Kim) 한국생활환경학회 2020 한국생활환경학회지 Vol.27 No.4

The changes of kinematic factors during archery shooting motion are still unknown in Korean traditional archery. This study investigated to evaluate of kinematic factors and each joint muscle strength during archery shooting motion in Korean traditional archers. Ten men Korean traditional archers were divided into two groups according to the shooting stance; parallel stance group (PSG, n=5) and oblique stance group (OSG, n=5). The 3-phase time of PSG was significantly longer than that of OSG during shooting motion (p<.01). On the other hand, there was no difference between the two groups in body weight movement measured by ground reaction force (NS). In the comparison of joint muscle strengths, dominant arm (draw arm) had significantly higher means in total upper limb muscle (TULS) with shoulder flexion+extension (SFES), shoulder external+internal rotation (SERIRS), total shoulder (TSS), wrist flexion+extension strength (WFES) than non-dominant arm(bow arm), respectively (p<.05, p<.001). As for the correlation between each variable, significant negative correlation was found between highest score and dominant body weight movement in the 3-phase time (p<.01). However, significant correlation was found among bowstring tension and average hand grip strength, non-dominant hand grip (NDhand grip), wrist extension (NWES), and shoulder external rotation strength (NSERS), respectively (p<.01). These results suggest that the muscular strength of joints in the dominant arms is an important factor for Korean traditional archery, and the parallel stance is might more advantageous to shoot than oblique stance.

교번으로 영전압 스위칭 되는 다중공진형 컨버터 토폴로지

김창선(Chang-sun Kim),박효식(Hyo-Sik Park),오용승(Yong-Seung Oh),김희준(Hee-Jun Kim) 전력전자학회 2002 전력전자학술대회 논문집 Vol.- No.-

In the resonant converters which can provide high efficiency and high power density, the resonant voltage stress is about 4 - 5 times the input voltage. it needs the power switch with high ratings This is a reason why the conduction loss is increased in this paper, it proposes the alternately zero voltage switched forward, flyback multi resonant converter topology for reducing the voltage stress using alternately zero voltage switching technique And the proposed AT forward MRC is experimentally considered about the loop gain with HP4194A network analyzer.

누가의 구원사

김창선(Chang-Sun Kim) 한국신약학회 2003 신약논단 Vol.10 No.2

아동의 신체조성과 골염량과의 관계

김창선 ( Chang Sun Kim ),박동호 ( Dong Ho Park ) 한국스포츠정책과학원(구 한국스포츠개발원) 2004 체육과학연구 Vol.15 No.2

사춘기에는 골량이 급격하게 증가하며 근육량, 체지방량 등의 신체구성과 함께 뼈에 있어서도 남녀차가 발생하는 것으로 알려져 있으나, 아동기의 골대사에 대해서는 거의 보고된 바가 없다. 따라서 본 연구의 목적은 사춘기 이전의 특정 연령의 남녀 아동들(남: 16명, 여: 19명)을 대상으로 신체적인 특징과 골대사와의 관계를 규명하고, 신체조성과 골밀도에 대한 성차를 알아보는데 있다. 평균연령 8.9±0.3세의 남녀 아동 35명을 대상으로 골염량 및 체지방량 등 신체조성의 측정은 골염량 측정기(DPX-L, Lunar, US)를 사용하였으며, 골대사 마커로서 소변으로 배출되어지는 피리지노린(Pyr) 및 데옥시피리지노린(Dpy), 칼슘(Ca), 인(P)의 농도를 측정하였다. 그 결과 전신 및 팔, 다리, 요추 등 모든 부위의 골염량은 신장(p<.01) 및 체중(p<.01)과 높은 정적 상관관계를 나타내었다. 체중 요소들과 골염량의 관계는 체지방량과는 모든 부위에서 유의한 상관관계를 나타내지 않았지만, 제지방체중과는 높은 정적 상관관계를 나타내었다(p<.01). 또한, 골염량 및 체중, BMI의 경우는 유의한 남녀차가 없었으나 제지방체중은 남자 아동이 유의하게 높은 수치를 나타내었다(p<0.05). 체지방량 및 체지방율의 경우는 여자아동이 각각 약 12%, 20% 높은 경향을 보였다(N.S.). 이상의 결과를 요약하여 볼 때, 사춘기 이전의 9세 아동들의 뼈에 있어서는 아직 남녀 차이가 나타나지 않지만, 근육량과 체지방량에서는 그 차이가 나타나기 시작하는 시기라고 할 수 있다. 아동기의 체중성장에 있어서는 규칙적인 운동을 통한 근육량의 증가가 골량의 증가에 바람직한 영향을 미치며, 아동의 뼈 건강 향상에 효과적으로 작용할 것으로 기대된다. Although bone mineral content (BMC) is rapidly increased in adolescence, it does not clear in childhood. The purpose of this study was to investigate the relationship between BMC and body composition of childhood as well as sex difference on BMC and body composition. We carried out the measurement of BMC of sixteen boys and nineteen girls (8.90±.3 years old). Total body and L2~4 BMC and body composition were measured by dual energy x-ray absorptionmetry (DPXL; LUNAR, USA), and urinary pyridinoline (Pyr), deoxypyridinoline (Dpy), calcium (Ca), phosphate (P) and creatine (Cre) were measured as the markers of bone metabolic turnover. BMC of all regions showed the positive correlation with physique such as height (p<.01) and weight (p<.01), respectively. Particularly, BMC was strongly related to the lean body mass (LBM)(p<.01), a constituent factor of body weight, but not between the body fat mass (BFM). Although there was no significant sex difference in other parameters including both body weight and height. LBM of boys was approximately 14% higher (p<.05) than that of girls with approximately 20% lower BFM. These results suggest that childhood was very important period because sex difference begins to appear in this prepubertal stage. In addition, the moderate or regular exercise which results in the increase of lean body mass might be an important factor for the bone health of 9 years old children through the increase of BMC.

국내 하지손상의 발생현황에 대한 분석

김창선 ( Chang Sun Kim ),최혁중 ( Hyuk Joong Choi ),김재용 ( Jai Yong Kim ),신상도 ( Sang Do Shin ),고상백 ( Sang Baek Koh ),이국종 ( Kug Jong Lee ),임태호 ( Tai Ho Im ) 대한외상학회 2008 大韓外傷學會誌 Vol.21 No.1

Purpose: We conducted this retrospective epidemiological study to assess the incidence and severity of lower extremity injuries in Korea Methods: For this study, we retrospectively reviewed nationwide lower-extremity injury data compiled from 2001 to 2003 based on the National Injury Database, what included National Health Insurance Corporation (NHIC), Car Insurance, and Industry Insurance data. Data were standardized in terms of demographic characteristics, region, and socioeconomic status by using NHIC data. To assess the degree of the injuries, we used the Modified Abbreviated Injury Scale (MoAIS), what has been changed from the International Classification of Disease-10 (ICD-10) code. By using the Excess Mortality Ratio-adjusted Injury Severity Score (EMR-ISS), we classified the degree of severity into four categories: mild, moderate, severe and critical. Results: From 2001 to 2003, lower extremity injuries increased slightly, with a yearly average of 2,437,335. Insurance data should that lower-extremity injuries were the most common, followed by upper-extremity injuries. Significant difference were seen in the numbers of lower extremity injuries based on gender and age. As for provinces, Seoul and Gyeongi provinces had the highest numbers of cases. Junlabukdo had the highest rate of 55,282 cases per 1 million people for standardized gender and population. The annual incidence of the insured patients with lower extrimity injuries was higher than the employer`s medical insurance contributions to the medical insurance program. Daily cases occur most often in May and June, with the lowest occurrences being in January and February. Conclusion: The result of this study shows that lower extremity injuries comprised common cause of all injuries. In addition, differences associated with gender, location and socioeconomic status were observed. Further studies are needed to find reasons and then this knowledge will allow strategies to prevent the lower extremity injuries.

고령 여성의 근육량과 골밀도, 기초체력과의 관련성

김창선(Chang-Sun Kim) 한국생활환경학회 2015 한국생활환경학회지 Vol.22 No.1

Several studies have shown that decreased muscle weight is a risk factor of elderly disease. The aim of the present study is to evaluate the relation between muscle weight and bone mineral density and physical fitness in elderly women. Seventy three elderly women(aged 67.5 ± 3.6 yrs) were evaluated and divided according to their muscle weight level in quartiles. Subjects were divided as follows: Quartile 1 (Q1; <32.9 kg; n=18), Quartile 2 (Q2; ≥33.0 and <35.6 kg; n=18), Quartile 3 (Q3; ≥35.7 and <37.0 kg; n=18), Quartile 4 (Q4; ≥37.2 kg; n=19). Body composition, bone mineral density(BMD) and basal physical fitness were compared between four groups according to muscle weight levels. Body muscle weight was measured by using body composition analyzer(Inbody720, Biospace, Korea) and BMD of the total body was also measured by using dual energy X-ray absorptiometry(DEXA). Pearson"s correlation coefficient and level of significance were used to evaluate the correlations between measurements. There were significant differences for height and weight according to quartiles of muscle weight level, respectively(p<.001), and BMI and %BF also significantly increased in the order of Q1, Q2, Q3, and Q4 group(p<.001). BMD of Q2, Q3, and Q4 group were significantly higher than that of Q1 group(p<.001), BMC of Q3, and Q4 group were significantly higher than that of Q2 group(p<.001) and that of Q2 group were also higher than that of Q1 group(p<.001), Most of basal physical fitness showed no significant differences among quartiles of muscle weight level(NS). Age was negatively correlated with total BMD, T??score and total BMC, respectively(p<.05), and height, weight, BMI and muscle weight showed a positive correlations with most of BMD and BMC, respectively(p<.05, p<.01). A negative correlation was found between weight and 2min walking and chair sit & reach, respectively(p<.05), and BMI showed negative correlations with back scratch and one leg stand, respectively(p<.05). %BF was negatively correlated with chair sit & reach and one leg stand, respectively(p<.05, p<.01). These results suggest that decrease of muscle weight result in reducing of BMD, and osteoporosis is occur by this reducing of BMD in elderly women. Moreover, the keep of muscle weight through the maintain body composition such as weight and BMI is beneficial to maintain BMD of elderly women.

트레드밀 운동이 고혈압 흰쥐의 골대사에 미치는 영향

김창선(Chang-Sun Kim) 한국생활환경학회 2012 한국생활환경학회지 Vol.19 No.5

There have been many researches that studied the influence of exercise on secondary bone loss by hypertension. However, the researches still have a little question. For a better understanding between exercise and bone mineral density (BMD), the purpose of this study was to examine the effects of treadmill exercise on bone metabolic turnover in Spontaneously Hypertension Rats(SHR). Six-week-old male, fourteen SHR, and seven Wister-Kyoto (WKY) rats were investigated on bone status including BMD and biomechanical markers from serum. After a week of stabilization, the rats were randomly divided into three groups: WKY control group (n=7, WKY), SHR control group (n=7, SC) and SHR treadmill exercise group (n=7, SE). Treadmill exercise training was performed at 20m/min, 60min/day, 5days/week for 16 weeks. All that rats were fed an commercial standard lab chow and allowed free access to tap water. At the end of the experimental period, the rats were sacrificed with blood drawn and femur were removed for analysis of BMD by dual energy x-ray absorptionmetry (DEXA). In SC group, blood pressure showed significant higher (p〈.001) than that of WKY group with a lower BMD(p〈.05), BMC(p〈.01), bone mass(p〈.01), serum Ca(p〈.01) and adjusted Ca(p〈.01). In SE group, blood pressure was significantly decreased (p〈.001), there was no change in BMD, BMC and bone mass as well as serum bone metabolic markers compared with SC group. Blood pressure was negatively correlated with all femur bone indexes and serum Ca concentration(p〈.01), and there was a positive correlation between femur bone indexes and serum Ca concentration(p〈.01). Results indicated that although SHR showed characteristics of osteoporosis, and treadmill exercise training improves blood pressure but does not prevent bone loss.