수중폭발에 의한 해중터널의 동적거동

홍관영,이계희,이성로 한국전산구조공학회 2018 한국전산구조공학회논문집 Vol.31 No.5

본 논문에서는 수중폭발(UE: underwater explosion)에 의한 해중터널(SFT: submerged floating tunnel)의 동적거동을 양 해법(explicit)를 이용하는 LS-DYNA에 의한 유한요소해석을 통하여 분석하였다. SFT의 유한요소모델은 원형단면의 강재 라이너에 콘크리트가 채워진 복합재 원형단면으로 고려되었다. 해중터널 시스템의 중앙부 100m 구간은 탄소성재료를 고려 한 솔리드(solid)요소로 상세하게 모델링하였으며, 양측 방향으로 각각 1km 구간에 대해서는 탄성재료를 고려하여 빔(beam) 요소로 이상화하여 모델링하였다. 사선계류시스템은 케이블(cable)요소를 적용하였으며, 수중폭발에 의한 동적거동시 수리동 적질량의 영향을 고려하기 위하여 원형단면에 대한 추가질량을 고려하였다. 또한 부력과 같은 상시하중을 초기조건으로 고려하기 위하여 동적완화해석(dynamic relaxation analysis)를 수행하였다. UE는 부력비(B/W)와 폭발지점으로부터 거리의 변화에 대해서 고려하였으며, 폭발의 규모는 천안함 합동조사보고서(2010)를 참조하여 TNT 360kg로 결정하였다. 수중폭발 해석결과, 폭발지점으로부터 SFT까지 거리는 관입량, 충격압력의 크기와 반비례 관계에 있고, 부력비(B/W)가 커질수록 계류장력도 커짐을 확인하였다. 그러나 사선계류라인의 계류각 변화는 SFT의 수평거동, 관입량, 계류력, 충격압력과의 연관성 을 찾을 수가 없었다. In this paper, to estimate the dynamic behavior of a submerged floating tunnel(SFT) by underwater explosion(UE), the SFT is modeled and analyzed by the explicit structural analysis package LS-DYNA. The section of SFT near to explosion point is modeled to shell and solid elements using elasto-plasticity material model for concrete tubular section and steel lining. And the other parts of the SFT are modeled to elastic beam elements. Also, mooring lines are modeled as tension-only cable elements. Total mass of SFT is including an added mass by hydrodynamic effect. The buoyancy on the SFT is considered in its initial condition using a dynamic relaxation method. The accuracy and the feasibility of the analysis model aree verified by the results of series of free field analysis for UE. And buoyancy ratio(B/W) of SFT, the distance between SFT and an explosion point and the arrangement of mooring line aree considered as main parameters of the explosion analysis. As results of the explosion analysis, the dynamic responses such as the dent deformation by the shock pressure are responded less as more distance between SFT and an explosion point. However, the mooring angle of the diagonal mooring system can not affect the responses such as the horizontal displacement of SFT by the shock pressure.

12주간의 농어촌 건강증진 운동프로그램 참여가 노인여성의 SFT와 EQ-5D에 미치는 영향

이중철,허안식,주성범 한국스포츠학회 2020 한국스포츠학회지 Vol.18 No.4

본 연구의 목적은 12주간의 농어촌 건강증진 운동프로그램 참여가 노인여성의 SFT와 EQ-5D에 미치는 영향에 대해 분석하여 농어촌 건강증진 운동프로그램의 효과성을 검증하는 것이다. 이를 위해 3개 보건진료소에서 각각 실험군과 대조군을 각각 34명과 17명씩 모집하였으며 2개 진료소는 농어촌 건강증진 운동프로그램을 운영하고 1개 진료소는 통제 군으로 사전사후검사만 실시하였다. 12주간의 농어촌 건강증진 운동프로그램은 스트레칭, 걷기운동 및 근저항 운동으로 구성하여 12주간 적용하였으며, 측정항목으로는 SFT와 EQ-5D로 하였다. 이에 따른 연구결과는 다음과 같다. 실험군의 SFT 항목인 의자에서 일어섰다 앉기, 2분 제자리 걷기 및 의자앉아 앞으로 굽히기와 EQ-5D에서 사전에 비해 사후에 유의한 차이가 나타났다. 이러한 결과를 볼 때, 농어촌 건강증진 운동프로그램은 하지 근력, 근지구력, 하지 유연성, 삶의 질이 긍정적인 영향을 미친다는 것을 알 수 있었다. 이러한 연구결과에 기반하여 상지 근력, 상지 유연성 등 보다 다양한 효과를 나타낼 수 있도록 농어촌 건강증진 운동프로그램으로 발전이 필요할 것으로 생각된다. The purpose of this study was to analyzing the effect of participation in the rural health promotion exercise program for 12 week on SFT and EQ-5D index. Three public health center 51 people each, and only two public health center operated rural health promotion exercise and one public health center only measures SFT and EQ-5D index. The rural health promotion exercise program consisted of stretching, walking exercise, and muscle resistance exercise and the effects on SFT and EQ-5D index were evaluated. The research results are as follows. The experimental group significantly increased standing and sitting in a chair, walking in place for 2 minutes, sitting and bending forward and EQ-5D index. These results it was found that the exercise program operated by the rural health promotion center has a positive effect on lower extremity muscle strength, muscular endurance, lower extremity flexibility, and quality of life. Based on these research results, it is thought that it is necessary to develop into an rural health promotion exercise program for the elderly to exhibit more diverse effects such as upper limb muscle strength and upper limb flexibility.

ON NONNIL-SFT RINGS

Ali Benhissi,Abdelamir Dabbabi Korean Mathematical Society 2023 대한수학회논문집 Vol.38 No.3

The purpose of this paper is to introduce a new class of rings containing the class of SFT-rings and contained in the class of rings with Noetherian prime spectrum. Let A be a commutative ring with unit and I be an ideal of A. We say that I is SFT if there exist an integer k ≥ 1 and a finitely generated ideal F ⊆ I of A such that x^k ∈ F for every x ∈ I. The ring A is said to be nonnil-SFT, if each nonnil-ideal (i.e., not contained in the nilradical of A) is SFT. We investigate the nonnil-SFT variant of some well known theorems on SFT-rings. Also we study the transfer of this property to Nagata's idealization and the amalgamation algebra along an ideal. Many examples are given. In fact, using the amalgamation construction, we give an infinite family of nonnil-SFT rings which are not SFT.

코어 안정화 트레이닝이 노인여성의 SFT체력과 균형능력에 미치는 영향

안순식,안용덕 한국스포츠학회 2016 한국스포츠학회지 Vol.14 No.3

본 연구는 노인여성을 대상으로 코어 안정화 트레이닝을 실시하여 SFT 체력과 균형능력에 미치는 영향을 규명하여 노인들에게 낙상예방과 더불어 적합한 운동 프로그램을 제공하기 위한 연구로 다음과 같은 결론을 얻었다. SFT 체력에 대한 이원반복측정 분산분석 결과에서 측정시기에 따른 주 효과는 상지유연성을 제외한 모든 항목(하지근력, 상지근력, 전신지구력, 민첩성 및 동적평형성, 하지 유연성, 심폐지구력)에서 통계적으로 상승효과를 나타내어 유의한 차이를 보였 고 측정시기와 그룹의 상호작용 효과는 하지근력, 상지근력, 전신지구력, 민첩성 및 동적평형성, 하지 유연성에서 유의한 차이가 있는 것으로 나타났으며, 그룹에 따른 주 효과는 SFT체력의 모든 항목에서 유의한 차이가 없는 것으로 나타났다. 균형능력에 대한 이원반복측정 분산분석 결과에서 측정시기에 따른 주 변화는 NSEO 내-외, 전-후, 움직인 거리, OLREO 내-외, 전-후, 움직인 거리, OLLEO 내-외, 전-후, 움직인 거리에서 통계적으로 유의한 차이를 보여 상승효과가 있는 것으로 나타났고, 측정시기와 그룹간의 상호작용 변화는 NSEO 내-외, 전-후, 움직인 거리, OLREO 내-외, 전-후, 움직인 거리, OLLEO 내-외, 전-후, 움직인 거리에서 유의한 차이가 나타났으며, 그룹에 따른 주 변화는 NSEO 전-후, 움직인 거리, OLREO 내-외, 움직인 거리, OLLEO 전-후, 움직인 거리에서 통계적으로 유의한 차이가 있는 것으로 나타났다. This study conducted core stability training with elderly women to examine its effects on SFT physical training and balance ability and provide good exercise programs for the elderly with fall prevention. The following conclusions were drawn. For two-way repeated ANOVA for SFT physical fitness, the main effect according to the measurement period statistically showed significant difference in all items but upper flexibility(lower strength, upper strength, general endurance, agility and dynamic balance, lower flexibility, and cardiorespiratory endurance) with an increased effect. The interaction effect between measurement period and group had a significant difference in lower strength, upper strength, general endurance, agility and dynamic balance, and lower flexibility. The main effect according to the group had no significant difference in all items of SFT physical fitness. For two-way repeated ANOVA for SFT physical fitness, the main effect according to the measurement period showed a statistically significant difference in med-lat, ant-post, and velocity moment for NSEO, med-lat, ant-post, and velocity moment for OLREO, and med-lat, ant-post, and velocity moment for OLLEO with an increased effect. The interaction effect between measurement period and group had a significant difference in med-lat, ant-post, and velocity moment for NSEO, med-lat, ant-post, and velocity moment for OLREO, and med-lat, ant-post, and velocity moment for OLLEO. The main effect according to the group had a significant difference in ant-post and velocity moment for NSEO, med-lat and velocity moment for OLREO, and ant-post and velocity moment for OLLEO.

화재 시나리오에 따른 철근콘크리트 해중터널의 손상도 분석

서지혜,한택희,박우선,한상훈,원덕희,Seo. JiHye,Han. Taek Hee,Park. Woo-Sun,Han. Sang-Hun,Won. Deok Hee 한국방재학회 2014 한국방재학회논문집 Vol.14 No.4

해중터널에 있어서 내화성능은 매우 중요하다. 만약 해중터널에 화재가 발생하였을 경우 온도하중에 의하여 큰 손상이 발생할 것이다. 이러한 국부적인 손상은 시스템 붕괴로 이어질 수 있다. 이러한 이유로 해중 터널의 내화성능은 반드시 정립되어야 한다. 해중터널의 내화성능을 제시하기 위해서는 다양한 화재조건에서 해중터널이 어떠한 손상 및 거동을 보이는지가 검토되어야 한다. 이에 본 논문에서는 다양한 화재 조건에서 해중터널이 어떠한 손상이 발생하는지에 대한 기초 연구를 수행하였다. 기존에 제시된 화재 시나리오를 이용하여 화재를 가정하였으며, 그에 따른 손상정도를 검토하였다. 본 연구는 향후에 해중터널의 내화기준을 수립하는 기초 연구 자료를 사용될 것이다. Fire resistance performance of the SFT (Submerged Floating Tunnel) is important one of the various researches. If fire break out in SFT, it is damaged by thermal loads. The damage of the SFT varies by type of fire. Structure of the SFT is able to collapse partially by fire scale and fire exposure time. For this reason, fire resistance design of the SFT must be suggested. Fire resistance performance of SFT could be investigating for fire resistance design of SFT. Fire condition could be expressed fire curves which are suggested by fire scale and fire exposure time. In this paper, temperature distributions of the SFT were investigated through FE analysis under various fire scenarios. Heat transfer analysis was applied to investigate conduction of heat by fire. And there was to draw the biggest influence fire condition to the SFT from FE analysis results. Also, preliminary study was performed for fire resistance design.

아쿠아로빅이 비만노인여성의 신체구성과 SFT체력 및 대사증후군 위험요인에 미치는 영향

송채훈(Chae-Hoon Song),양창인(Chang-in Yang),고무송(Moo-Song Ko) 한국발육발달학회 2017 한국발육발달학회지 Vol.25 No.2

Purpose. The purpose of this study is to analyze the effects of aquarobic on body composition, SFT, and metabolic syndrome and contribute to health promotion and provision of an effective exercise program for obese elderly women. Methods. 20 obese elderly women were divided into the aquarobic group(n=10) and the control group(n=10) and a 12-week program for them was conducted with them three times per week. body composition was measured by weight and body fat, SFT result was measured by lower strength, upper strength, general endurance, lower flexibility, upper flexibility, agility, and dynamic balance, and metabolic syndrome risk factors were measured by waist girth, blood pressure(systolic, diastolic), and blood(glucose, HDL-C, and TG). Data processing using SPSS 19.0 was made by two-way repeated ANOVA and a difference according to the exercise period by group was measured by the paired-samples t-test. Results. The results are as follows. First, The aquarobic group showed a significant effect by improving in all measurement items of body composition compared with pre-exercise. Second, the auqarobic group showed a significant effect by improving in all measurement items of SFT result except flexibility compare with pre-exercise. Third, the aquarobic group showed a significant effect by improving in all measurement items of metabolic syndrome risk factor except blood pressure(diastolic) compared with pre-exercise. Conclusion. The results suggest that aquarobic had effects on body composition, SFT result, and metabolic syndrome risk factors in obese elderly women. Obese elderly women could assimilate themselves to aquarobic exercise as aquarobic is aerobic and unloaded exercise. Moreover, adding music and rhythm may make them more pleasant and contribute to positive exercise effects. Therefore, aquarobic should be recommended as an effective training method for body composition, SFT results, and metabolic syndrome risk factors in obese elderly women.

기(氣)체조 운동중재가 여성고령자의 혈당, 혈중지질, 체력(SFT) 변화에 미치는 영향

김지선(Ji-Sun Kim) 한국산학기술학회 2017 한국산학기술학회논문지 Vol.18 No.6

본 연구는 기체조 운동중재가 여성고령자의 혈당, 혈중지질, 체력(SFT) 변화에 미치는 영향을 분석하고, 이를 통해 여성고령자들의 건강증진 활동을 위한 기체조 운동중재의 효용성을 규명하는데 목적이 있다. 연구대상은 80세 이상 여성고령자 총 24명을 각각 기체조집단(n=12)과 통제집단(n=12)으로 나누고, 24주간 주5회 1일 60분씩 프로그램을 실시하였다. 자료의 분석은 SPSS WIN 20.0으로 반복측정 변량분석(Repeated Measures ANOVA)을 실시하였으며, 그 결과 첫째, 혈당은 기체조집단이 통제집단 보다 유의하게 낮아진 것으로 나타났다. 둘째, 혈중지질은 기체조집단이 통제집단 보다 중성지방(TG)이 유의하게 감소되었으며, 총콜레스테롤(TC), 고밀도지단백(HDL-C), 저밀도지단백(LDL-C)은 유의한 차이가 나타나지 않았다. 셋째, 체력(SFT)은 기체조집단이 통제집단 보다 하지근력, 하지유연성, 전신지구력 모두 유의하게 높아진 것으로 나타났다. 이러한 결과로 기체조는 여성고령자들의 혈당, 중성지방(TG) 감소와 SFT체력(하지근력, 하지유연성, 전신지구력) 향상에 영향을 미쳐 여성고령자 운동처방 프로그램으로의 효용성을 기대할 수 있다고 사료된다. This study analyzed the influence of Qigong exercise intervention upon a change in glucose, blood lipid, and SFT(senior fitness test) of elderly women and to closely examine the efficacy of a Qigong exercise intervention to promote the health of older women. As research subjects, 24 elderly women aged over 80 were dividedinto Qigong group(n=12) and control group(n=12), respectively, and the program was carried out for 60 minutes per a day, five times per week for 24 weeks. Data were analyzed using SPSS WIN 20.0, repeated measures ANOVA. The Qigong group had a significantly lower glucose level than the control group. Second, the blood lipid and neutral fat(TG) was reduced significantly in the Qigong group than the control group. The total cholesterol(TC), high-density lipoprotein(HDL-C), and low-density lipoprotein(LDL-C) did not show a significant difference. Third, as for SFT, the leg strength, leg flexibility, and total body endurance were significantly higher in the Qigong group than in the control group. Therefore, Qigong has an influence on the reduction in glucose and neutral fat(TG) and upon the improvement in SFT(leg strength, leg flexibility, and total body endurance) of elderly women, and mayshow effectiveness as an exercise prescription program for older women.

16주 스텝-밴드 운동이 전기·후기 노인의 체구성과 SFT에 미치는 영향

안동수(An, Dong-Su),변용현(Byun, Young-Hyun) 한국체육과학회 2016 한국체육과학회지 Vol.25 No.4

The purpose of this study was to determine the effects of step-band exercise on body composition and SFT(Senior Fitness Test) in the Young-Old(YOA, n=13) and the Old-Old Adults(OOA, n=19). The step-band exercise needed equipments-a steeper and a thera band was performed for 90 minutes, 2 times a week, for 16-week. Body composition, SFT were measured before and after the step-band exercise. To analyze effects of exercise results, Two-way repeated measures ANOVA was carried out by each variable. The statistical significance level was set for α=.05. The results of this study are as follows: First, Body weight, BMI and WHR significantly were decreased in all group after 16-week exercise(p<.05). BFM(body fat mass), %BF were significantly decreased in OOA after 16-week exercise(p<.05). But MM(muscle mass) was statistically increased in OOA(p<.05). Second, there was no significant an interaction related to SFT between a time and a group and the step-band exercise improved all measurements of SFT in all groups(p<.05). There was no significant differences between two groups(p<.05) in Arm curl, 2-Min step, back stretch area. These results suggest that step-band exercise improves body composition and SFT in young- and old-old adults. In this study, the step-band exercise was especially more effective to the OOA than the YOA.

Active Core 운동이 뇌졸중환자의 SFT와 족부압력에 미치는 영향

박기덕(Park, Gi-Duck),윤성덕(Yoon, Seong-Duek) 한국체육과학회 2013 한국체육과학회지 Vol.22 No.5

The purpose of this study is to analyze the effects of active core training using all kinds of tools for 12 weeks on the Senior Fitness Test (SFT) result and foot pressure of patients who receive surgical treatment and drug therapy after a stroke. The subjects of this study were 20 patients at a rehabilitation welfare center for the elderly and they were divided into a training group (11 patients) and a control group (9 patients). The exercise method was proprioceptive exercise aimed at stimulating and training somatic senses and the subjects conducted exercise using a sling on an aero-step. The measurement items included body composition test, SFT, and foot pressure and training effect was examined. The 12-week exercise led to the following result. According to the SFT analysis result, stroke patients" active core training using a togu resulted in significant differences between the training group and the control groupin sitting and standing, raising a dumbbell, walking for six minutes, holding hands behind the back, and 2.44M walking round. There was no significant difference between the training group and the control group in foot pressure analysis. To sum up this study result, trunk stabilization exercise, in other words, active core training using a togu resulted in significant improvement in functional physical strength of stroke patients and therefore it can be said that trunk stabilization exercise has an intervention effect. Although there was no significant difference in foot pressure analysis, foot pressure distribution at the neutral position was seen, which suggests that there was influence on balance. Therefore, the researcher hopes that continuous development and study of rehabilitation programs will be made through more clinical applications.

8주 필라테스 운동이 노인여성의 신체조성, SFT, CRP 및 IL-6에 미치는 영향

김문정,허유섭 한국체육과학회 2024 한국체육과학회지 Vol.33 No.2

The purpose of this study was examine the effects of 8 weeks of pilates exercise on Body Composition, SFT, CRP and IL-6 in Older Women. The subjects were composed of pilates exercise group(PEG, n=8) and control group(CON, n=8). The exercise program was conducted for 8-weeks, twice a week for 60 minutes, with RPE 13-15 intensity, and gradually increased the number of sets and the number of repetitions in consideration of the physical strength of the subject. Here's the result: 1. There was no significant difference in body weight, lean body mass, fat mass, body fat percentage, BMI, and WHR in the change in body composition. 2. In SFT, interactions were seen in the chair stand test, Biceps Curl Test, and 2.44m Up-and-go (p<.05), in PEG (p<.05), and in CON there was no significant difference. The Chair Sit and Reach Test, Back Scratch Test, and 2-minute Step Test did not show any interaction effects. 3. There was no significant difference between CRP and IL-6 in terms of interaction and main effects. Summing up the above results, it was found that the Pilates exercise program performed on elderly women for 8 weeks showed no change in body composition and inflammatory markers, but it had a positive effect on the chair stand test, Biceps Curl Test, and 2.44m up-and-go of SFT. The absence of changes in body composition and inflammatory indicators is thought to be a phenomenon caused by a rather short period of exercise, and it can be suggested that it is necessary to investigate these changes by prolonging the exercise program of the elderly.