For the past 70 years, an intense rivalry has persisted on the Korean Peninsula, and North Korea's nuclear and missile threats are becoming increasingly imminent. Facing a shortage of military resources, South Korea has pursued a national defense reform, significantly reducing the number of units and troops while focusing on ground forces. However, North Korea's strategic objective of unifying South Korea through surprise attacks, prompt responses, and combined nuclear and missile assaults remains unchanged. The central issue in this context revolves around determining the appropriate size of the Korean military's standing forces. This study employs the concept of net assessment as a novel method to ascertain the optimal size of the Korean military. Threats, strategic objectives, doctrine, and unit rotations are simultaneously considered from the enemy's perspective. In anticipation of security risks on the Korean Peninsula, an acceptable troop size will be proposed using the net assessment approach to calculate the appropriate standing force size.

In the case of dry storage facilities, slipping of the cask or tip-over are dangerous phenomena. For this reason, in dry storage facilities, measures against slipping and tip-over or related safety evaluations are important. Accidental conditions that can cause cask slippage and tip-over in dry storage facilities include natural phenomena such as floods, tornadoes, tsunamis, typhoons, earthquakes, and artificial phenomena such as airplane crashes. However, among natural phenomena, earthquakes are the most important natural phenomenon that causes tip-over. Also, many people had the stereotype that Korea is an earthquake-safe zone before 2016. However, earthquakes become a major disaster in Korea due to the 2016 Gyeongju earthquake and the 2017 Pohang earthquake, followed by the Goesan earthquake in October 2022. In this paper, seismic analysis was performed based on dry storage facilities including multiple casks. Design variables for the construction of an analysis model for dry storage facilities were investigated, and seismic analysis was performed. To evaluate tip-over accident during earthquake, seismic load was used from 0.2 g PGA to 0.8 g PGA and these earthquakes were followed Design Response Spectrum (DRS) in RG 1.60. The friction coefficient of concrete pad was used from 0.2 to 1.0. As a result of the analysis, tip-over accident could not find in the analysis from 0.2 g to 0.6 g. However, tip-over was appeared at friction coefficients of 0.8 and 1.0 at 0.8 g PGA. Tip-over angular velocity of cask was derived by seismic analysis and was compared with formula and tip-over analysis results. As a result, a generalized dry storage facility analysis model was proposed, and dry storage facility safety evaluation was conducted through seismic analysis. Also, tip-over angular velocity was derived using seismic analysis for tip-over analysis.

본 연구는 경남지역 대나무림에 대한 면적 및 입목축적량 산정과 함께 탄소저장량을 추정하기 위하여 수행되었다. 현재 산림청의 임업통계연보에는 대나무림에 대한 공간정보인 면적만 제시되고 있을 뿐, 입목축적에 대한 정보는 전혀 제공되고 있지 못하다. 따라서 본 연구에서는 최근에 만들어진 대나무 재적표를 활용하여 경남지역의 입목축적량을 계산하고, 여기에 탄소배출계수를 이용하여 탄소저장 량을 계산하였다. 대나무림에 대한 면적은 1/5,000 수치임상도에서 추출하였으며, 입목축적을 산정하기 위해 현지조사한 표준지 자료를 활용하였다. 표준지의 대나무는 개체목 별로 흉고직경과 수고에 재적표를 적용하여 표준지의 재적을 산정하였다. 경남지역 대나무의 공간분포 면적은 총 6,038ha로서, 전국 대나무림(20,262 ha)중 약 30%를 차지하는 것으로 나타났다. 경남지역 중에서는 하동군이 가장 많은 면적인 1,027 ha가 분포하는 것으로 나타났다. 경남지역의 시계열적인 분포면적 변화는 2013년 대비 2022년에 약 20.3% 감소하였으 며, 2019년 대비 약 0.4%가 감소하였다. 경남지역 대나무의 입목축적량은 2022년말 현재 148,510 ㎥인 것으로 계산되었으며, ha당 축적은 약 25 ㎥으로 나타났다. 그리고 경남지역 대나무 숲의 이산화탄소저장량은 287,277 tCO2 이었으며, ha당 저장량은 47.6 tCO2 인 것으로 나타났다.

Compared to the prevalence of advertising targeted at teens, our understanding of their vulnerability to advertising has been limited due to the cognitive/developmental view adopted by most previous research. However, cognitive development is not the most significant aspect that differentiates adolescents from adults. Adolescence is when teenagers start to take on more responsibility in defining themselves and become more skilled at using consumption to construct and signal their identity. On one hand, teens have a growing desire to express their unique identity as autonomous and distinctive individuals, separate from their family and differentiated from others. On the other hand, they are nearly obsessed with what others think about them, striving to belong to a group and feeling devastated by signs of disapproval from peers. This conflict between the need for assimilation and the need for differentiation is especially pronounced during adolescence when teenagers increasingly seek the approval of their peers while expressing their uniqueness. As a result, their sense of self is in a constant state of flux. This "shaky" self-identity has been shown in previous research to coincide with low self-esteem, which is associated with a high level of materialism.

Background: Pilates exercises are used for body shape correction because they can achieve correct posture alignment through spinal stabilization. Objects: This study aimed to determine whether the use of reformers increases the effectiveness of Pilates core exercises on body alignment in standing. Methods: The study included 30 women without known diagnoses of musculoskeletal and neurological disorders or cancer. Those who had taken more than 10 Pilates lessons were excluded. The participants were randomly assigned to either the reformer exercise group or the mat exercise group, and interventional Pilates exercises were performed for 60 minutes a day, three times a week, for a total of 8 weeks. Ten movements of the reformer and mat Pilates core exercise programs were included. Exbody® 9100 MOMI musculoskeletal analysis equipment (Exbody Inc.) was used to assess the alignment of the standing posture in the frontal plane. Results: As a result of comparing the differences within and between the groups before and after the intervention using the two-way mixed analysis of variance test, height differences in the head, pelvis, left and right, shoulders, scapulas, knees, and ankles in the frontal plane after the intervention were found in both groups. For example, the left-right symmetry of the body alignment in the standing posture was significantly improved within each group (p < 0.05). However, no significant difference was found between the groups (p > 0.05). Conclusion: Both the reformer and mat Pilates core exercises were effective for standing posture alignment, which has clinical significance. If an exercise program is developed based on the analysis of movements necessary for posture improvement and the target muscles to be strengthened, the same effect can be achieved only with mat exercise without using the reformer equipment at the beginner stage.

Background: Neuromuscular electrical stimulation (NMES) is used for muscle strengthening. While voluntary muscle contraction follows Henneman et al.’s size principle, the NMES-induced muscle training disrespects the neurophysiology, which may lead to unwanted changes (i.e., declined balance ability). Objects: We examined how the balance was affected by abdominal muscle training with the NMES. Methods: Fifteen young adults (10 males and 5 females) aged between 21 and 30 received abdominal muscle strengthening with NMES for 23 minutes. Before and after the training, participants’ balance was measured through one leg standing on a force plate with eyes open or closed. Outcome variables included mean distance (MDIST), root mean square distance (RDIST), total excursion (TOTEX), mean velocity (MVELO), and 95% confidence circle area (AREA) of center of pressure data. Two-way repeated measures analysis of variance was used to test if these outcome variables were associated with time (pre and post) and vision. Results: All outcome variables were not associated with time (p > 0.05). However, all outcome variables were associated with vision (p = 0.0001), and MVELO and TOTEX were 52.4% (45.5 mm/s versus 95.6 mm/s) and 52.4% (364.1 mm versus 764.5 mm) smaller, respectively, in eyes open than eyes closed (F = 55.8, p = 0.0005; F = 55.8, p = 0.0005). Furthermore, there was no interaction between time and vision (F = 0.024, p = 0.877). Conclusion: Despite the different neurophysiology of muscle contraction, abdominal muscle strengthening with NMES did not affect balance.

리튬-이온 전지 기술의 발전과 함께 다량의 리튬 사용에 따라 리튬-이온 전지에 대한 수요와 공급의 균형이 무너지고 있으며, 따라서 리튬을 대체할 수 있는 차세대 이차 전지의 개발이 필요해지고 있다. 최근 친환경적이며, 값싸며 안전 하고, 다가의 전자를 활용할 수 있는 아연 이온을 활용하는 수계 아연-이온 전지가 주목받고 있다. 그럼에도 불구하 고 아연-이온 전지에 사용될 수 있는 전류 집전체에 대한 개발 연구는 거의 없으며, 특히 현재 사용되고 있는 금속 기반의 전류 집전체는 그 무게가 무거워 실용적으로 사용되기 힘들다. 본 연구에서는 접착 특성이 매우 우수한 키틴 바인더를 사용하여 집전체 없이 지탱이 가능한 전극을 개발하였으며 아연-이온 전지에서의 그 특성을 평가하였다. 전 극 제조는 전통적인 코팅법과 스핀 코팅법을 사용하여 비교하였으며, 스핀 코팅이 더 균일한 전극 형성과 함께 더 우 수한 배터리 성능을 나타냄을 확인하였다.

Background: Neuromuscular electrical stimulation (NMES) is a physical modality used to activate skeletal muscles for strengthening. While voluntary muscle contraction (VMC) follows the progressive recruitment of motor units in order of size from small to large, NMES-induced muscle contraction occurs in a nonselective and synchronous pattern. Therefore, the outcome of muscle strengthening training using NMES-induced versus voluntary contraction might be different, which might affect balance performance. Objects: We examined how the NMES training affected balance and proprioception. Methods: Forty-four young adults were randomly assigned to NMES and VMC group. All participants performed one-leg standing on a force plate and sat on the Biodex (Biodex R Corp.) to measure balance and ankle proprioception, respectively. All measures were conducted before and after a training session. In NMES group, electric pads were placed on the tibialis anterior, gastrocnemius, and soleus muscles for 20 minutes. In VMC group, co-contraction of the three muscles was conducted. Outcome variables included mean distance, root mean square distance, total excursion, mean velocity, 95% confidence circle area acquired from the center of pressure data, and absolute error of dorsi/plantarflexion. Results: None of outcome variables were associated with group (p > 0.35). However, all but plantarflexion error was associated with time (p < 0.02), and the area and mean velocity were 37.0% and 18.6% lower in post than pre in NMES group, respectively, and 48.9% and 16.7% lower in post than pre in VMC group, respectively. Conclusion: Despite different physiology underlying the NMES-induced versus VMC, both training methods improved balance and ankle joint proprioception.

대용량 화학 및 청정에너지의 운반체인 수소는 석유화학 산업 및 연료전지 등에서 많이 활용되는 중요한 산업용 기체이다. 특히 수소는 주로 증기개질 및 가스화를 통해 화석 연료에서 생성되며 부산물로 이산화탄소가 발생한다. 따라서 고 순도 수소를 얻기 위해서는 이산화탄소를 제거해야 한다. 본 총설에서는 배러 단위[1 Barrer = 10−10 cm3 (STP) × cm / (cm2 × s × cmHg)]로 보고된 이산화탄소로부터 수소를 분리하는 프리스탠딩 고분자 분리막 및 혼합매질 분리막에 초점을 맞추었 다. 최근 보고된 다양한 논문들을 분석하여 분리막의 구조, 형태, 상호 작용 및 제조 방법에 대해 논의하고 구조-물성 관계를 이해하여 향후 더 나은 분리막 소재를 찾는 데 도움이 되고자 한다. 다양한 분리막의 성능 및 특성 검토를 통해 수소/이산화 탄소 분리에 대한 Robeson 성능 한계선을 제시하고, 가교, 혼합 및 열처리 등의 기술을 사용하여 분리 특성을 개선하는 다양 한 혼합매질 분리막에 대해 논의하였다.

Background: Theoretically, balance is affected by the height of center of mass (COM) during quiet standing. However, no one examined this in humans with variables derived from the center of pressure (COP). Objects: We have conducted balance experiment to measure COP data during quiet standing, in order to examine how the COP measures were affected by the height of COM, vision, floor conditions, and gender. Methods: Twenty individuals stood still with feet together and arms at sides for 30 seconds on a force plate. Trials were acquired with three COM heights: 1% increased or decreased, and not changed, with two vision conditions: eyes closed (EC) and eyes open (EO), and with two floor conditions: unstable (foam pad) and stable (force plate) floor. Outcome variables included the mean distance, root mean square distance, total excursion, mean velocity, and 95% confidence circle area. Results: All outcome variables were associated with the COM height (p < 0.0005), vision (p < 0.0005), and floor condition (p < 0.003). The mean velocity and 95% confidence circle area were 5.7% and 21.8% greater, respectively, in raised COM than in lowered COM (24.6 versus 23.2 mm/s; 1,013.4 versus 832.3 mm2). However, there were no interactions between the COM height and vision condition (p > 0.096), and between the COM height and floor condition (p > 0.183) for all outcome variables. Furthermore, there was no gender difference in all outcome variables (p > 0.186). Conclusion: Balance was affected by the change of COM height induced by a weight belt in human. However, the effect was not affected by vision or floor condition. Our results should inform the design of balance exercise program to improve the outcome of the balance training.

Morphology control of a graphene nanosheet (GNS) is important for graphene-based battery electrodes to exhibit the increased practical surface area and the enhanced ion diffusion into the nanosheets. Nevertheless, it is very difficult to minutely control the shape of graphene nanosheets based on the conventional GNS suspension methods. In this work, we fabricated wrinkle textures of free-standing GNS for large area using Langmuir–Schaefer technique. The wrinkles are oriented vertically to the direction of the monolayer compression. The textured structure of GNS was obtained by cross-deposition of each layer with controlling the orientation of the wrinkle direction. These wrinkles can cause Li-ion to diffuse into the voids created by them and raise the specific surface area between the GNSs. Consequently, as a prospective anode for Li-ion battery, the wrinkled GNS multilayer, exhibits the high specific capacity of ~ 740 mAh g− 1 at 100 mA g−1 and the great power capability with ~ 404 mAh g− 1 being delivered even at 2 A g− 1. Furthermore, outstanding cycle performance of the wrinkled GNS multilayer is achieved over 200 cycles at 300 mA g−1 with high Coulombic efficiency of ~ 96%.

Background: Prolonged standing during work causes a lower extremity pain and disorders. Patellofemoral pain syndrome (PFPS) is one of the common diagnoses of the knee pain. Although the etiology of PFPS is not completely understood, it is considered to be multifactorial. Objects: The purpose of this study was to investigate difference in strength of knee muscles, quadriceps:hamstring muscles strength ratio (Q:H ratio), asymmetry ratio of knee muscles strength and dorsiflexion range of motion (ROM) between standing workers with and without PFPS. Methods: Twenty-eight standing workers with PFPS and 26 age-, height-, and weightmatched standing workers without PFPS participated in this study. A tension sensor measured knee muscle strength, and motion sensor measured dorsiflexion ROM. The asymmetry ratio of knee muscles was calculated by a specific formula using the knee muscles strength of the dominant side and the sound side. An independent t-test was used to identify significant differences in the strength, ROM, Q:H ratio, and asymmetry ratio between the PFPS and normal groups. Results: The standing worker with PFPS have significantly lower dorsiflexion ROM (p < 0.000) and higher asymmetry ratio of the hamstring muscles strength (p < 0.000) compare to the standing worker without PFPS. No significant differences were seen in the strength of quadriceps muscle and hamstring muscles, Q:H ratio, and asymmetry ratio of quadriceps muscle strength. Conclusion: There was a significant difference in the asymmetry ratio of the isometric hamstring muscle strength. This finding suggests that the asymmetry ratio of isometric hamstring muscle strength may be more important than measuring only the hamstring muscle strength of the PFPS side. Furthermore, the results of this study showed a significant difference in dorsiflexion ROM between the standing industrial workers with and without PFPS. Dorsiflexion ROM and isometric hamstring muscle strength should be considered when evaluating the subjects with PFPS.

Free-standing hybridized electrode consisting of double-walled carbon nanotubes (DWNTs) and activated carbon have been fabricated for flexible supercapacitor applications. The xanthan-gum, used in our methodology, showed high ability in dispersing the strongly bundled DWNTs, and was then effectively converted to activated carbon with large surface area via chemical activation. The homogeneously dispersed DWNTs within xanthan-gum derived activated carbon acted as both electrical path and mechanical support of electrode material. The hybridized film from highly dispersed DWNTs and activated carbon was mechanically strong, has high electrical conductivity, and exhibited high specific capacitance of 141.5 F/g at the current density of 100 mV/s. Our hybridized film is highly promising as electrode material for flexible supercapacitors in wearable device.

Background: The longitudinal arch is important for individuals with pes planus. The toe spread out exercise (TSO) has been widely used to continuously support the longitudinal arch by increasing the abductor hallucis (AbdH) muscle activation. However, the AbdH muscle is commonly lack of the sufficient activation during the TSO especially in individuals with pes planus. Objects: This study was performed to investigate the effect of arch support on the muscle activity and strength of the AbdH during TSO in standing position in individuals with pes planus. Methods: Twenty subjects with pes planus between 20 and 30 years of age participated in this study. The muscle activity and strength of the AbdH were measured using surface EMG system and the Smart KEMA tensiometer system. The AbdH muscle was evaluated during TSO between individuals with and without longitudinal arch support in standing position. The longitudinal arch was supported by using the insole. The paired t-test was used. The level of statistical significance was set at α = 0.05. Results: The muscle activity and strength of the AbdH during TSO with arch support in standing position was significantly greater than that without arch support. Conclusion: The muscle activity and strength of the AbdH during TSO in standing position can be influenced by the longitudinal arch support in individuals with pes planus. The AbdH strengthening during TSO in standing with arch support can be recommended especially in individuals with pes planus in the clinical settings.

Background: The range of pelvic tilt is one of modifiable risk factors in preventing the lower back pain. Objects: The purpose of this study were to compare the range of pelvic tilt motion by testing position and sex. Methods: One hundred five young adults (61 females and 44 males) agreed to participate in measuring the anterior and posterior pelvic tilt with the PALM (Palpation Meter) in sitting and standing. The range of pelvic tilt motion was defined as the difference between the pelvic anterior and posterior tilt angles. Results: In general, the anterior pelvic tilt was greater (p < 0.01) in standing than in sitting and the posterior pelvic tilt was lesser (p < 0.01) in sitting than in standing. The anterior pelvic tilt in sitting and standing was greater (p < 0.01) in the females than in the males. However, the effect of sex on the posterior pelvic tilt was only significant in sitting (p < 0.01), but not in standing (p = 0.78). The range of pelvic tilt was greater (p = 0.03) in sitting but not significantly (p = 0.07) affected by the sex. Conclusion: The pelvic tilt motion in these young adults showed large variability and further studies are needed to understand better its relationship to the prevalence of the lower back disorders.

본 연구는 복싱 잽 동작 시 제자리 스텝의 사용이 운동역학적 요인들에 미치는 영향을 분석 하는데 목적이 있었다. 이를 위해 최근 1년간 근골격계에 상해가 없었던 오른손잡이 스탠스 유형의 대학교 복싱 선수 8명(나이: 20.38±0.52 yrs, 신장: 172.38±5.80 cm 체중: 63.45±8.56 kg, 경력 6.00±1.07 yrs)이 실험에 참여하였다. 잽 동작 시 제자리 스텝 사용이 운동역학적 요인들에 미치는 영향을 검증하기 위하여 대응표본 t-test(α = .05) 통계방법을 사용하였으며 다음과 같은 결과를 도출하였다. 첫째, W.S(with-step) 가 N.S(non-step) 보다 더 큰 충격력을 나타내었고, 근육의 활성도는 낮은 것으로 분석되었다. 둘째 W.S가 인체 분절의 전방의 속도의 영향을 미쳐서 골반과 발 분절이 더 빠르게 이동하는 것으로 분석되었다. 셋째, W.S는 골반의 회전 움직임이 더 빠른 것으로 나타났다. 넷째, W.S는 N.S보다 상대적으 로 오른발과 왼발에 의해서 발생된 전방의 지면반발력이 더 큰 것으로 분석되었다. 이를 통해서 복싱 잽 동작 시 제자리 스텝의 사용은 지면반발력을 증가시켜 인체 분절의 이동 속도와 회전 움직임에 영향을 미 치는 것으로 나타났다. 따라서 더 빠르고 민첩한 움직임을 가능케 하여 상대적으로 적은 근육의 사용으로도 더 큰 충격력을 내는 것으로 확인되었다. 그러므로 복싱의 잽 동작 시 효율적으로 상대방에게 큰 충격력 을 전달하기 위해서는 제자리 스텝을 동반하는 것이 효과적으로 분석된다.

As the importance of three-dimensiona (3D) nano patterns and structures has recently emerged, interest in the study of 3D structures of block copolymers has increased. However, most existing studies on block copolymer 3D patterns on substrates are limited to simple 3D structures such as a multi-layered forms. In this study, we propose an experimental method for realizing free-standing 3D block copolymer patterns on substrates using an e-beam lithographic template and film transfer method. The block copolymer 3D structure formed in wide hole templates are similar to simple multi-layered structures; however, as the width of the hole template become narrower, more complex block copolymer 3D structures are formed in which the upper and lower layer structures are interconnected. Furthermore, we introduce a method to fabricate novel block copolymer structures in which the 2D planar structures are connected to 3D complex structures. Proposed 3D block copolymer fabrication method provides a framework for generation of unconventional 3D structures of block copolymer, which can be useful for next generation 3D devices.

Background: Stroke patients require arm movement exercising for various stimulations in standing position for various stimulations rather than in a sitting position because they require integrated skillful movements, such as stretching, holding, and controlling. Objective: This study was conducted to provide foundational clinical data about lower limb global synkinesis in stroke patients using arm movements in a standing position. Design: Randomized controlled trial. Methods: The subjects were divided into a control group (n = 10) and an experimental group (n = 10), and a pre-test was conducted to evaluate leg global synkinesis (GS) and balance. Intervention method is stretching an arm to hold a ball, repeating supination and pronation of the hand only while maintaining the arm extended as much as possible, repeating shoulder abduction and adduction while holding the pegboard. This was followed by a three-week intervention during which re-measurement was conducted in the same way as was done for the pre-test. Results: The control group showed a significant difference in GS and balance during plantar flexion (p<.05), and the experimental group showed a significant difference in GS and balance during all movements (p<.05, p<.01, respectively). There was a significant difference in GS and balance between the two groups during dorsiflexion (p<.05, p<.01, respectively). Conclusion: The findings demonstrate that human arm movements in a standing position can reduce GS in the affected limb, and balance can be improved by stimulating the surrounding tissues of the affected limb and changing them positively.