특수작전부대는 아프간 전쟁과 이라크 전쟁을 겪으면서 합동작전 수행 면 에서 전쟁 승리에 중요한 역할을 수행하였다. 본 연구의 목적은 특수작전 의 발전과정에서 한국군 특수작전을 진단하고, 향후 발전방향을 제시하 는 데 있다. 이를 위해 한미 특수작전을 비교하여 분석하였다. 연구 결과 특수작전은 고대로부터 수행되었으며, 전쟁 승리에 결정적으로 기여하였 다고 평가할 수 있었다. 또한 특수작전의 발전과정을 전쟁양상의 변화와 전쟁의 유형을 기초로 병력중심→화력중심→현대적→첨단화된 특수작전 으로 발전하는 것으로 정립하고, 이를 기초로 미군의 특수작전 발전과정 과 한국군 특수작전의 발전과정을 분석하여 비교하였다. 향후 한국군 특 수작전은 첨단화된 특수작전으로 발전해 가야 하며, 미래 다영역작전을 수행하기 위한 작전수행개념은 정보중심의 네트워크중심전 수행, 조직편 성은 합동특수작전사령부를 평시부터 편성하고 유관기관과의 통합된 조 직 확충, 무기체계는 AI기반의 최첨단 무기체계를 확충할 것을 제안하였 다. 본 연구는 특수작전의 기원과 발전과정에서 한국군 특수작전의 발전 을 연구한 최초의 연구로서 의의가 있다고 본다. 한국군 특수작전은 첨 단화된 특수작전으로 발전하기 위해 본 연구에서 제시한 사항 등이 신속 히 실현되기를 기대한다.

현대 건설산업 분야에서 철근콘크리트는 반영구적인 재료로 인식되어 가장 많이 사용되고 있다. 하지만 콘크리트의 노후화 및 수분 용해 현상 등으로 생긴 균열을 통해 강재의 부식이 발생하게 된다. 이러한 부식은 철근콘크리트의 거동과 구조물의 내구성을 저하시키기 때문에 근본적인 원인인 강재를 대체할 필요가 있다. 최근 건설산업에서 복합재료는 높은 강도, 낮은 중량, 부식에 대한 우 려가 없어 주목받고 있는 재료이다. 복합재료는 섬유와 기지재료로 사용되는 수지에 따라 재료의 특성이 달라지게 되며 이중 탄소섬유 를 활용한 복합재료 CFRP은 복합재료 중 가장 뛰어난 성능을 보여준다. 따라서 본 연구에서는 뛰어난 성능을 보여주는 CFRP와 경제 성을 고려하여 탄소섬유와 유리섬유를 혼합한 CFRP Hybrid를 사용하여 강재의 대체품으로 사용가능성을 확인하고자 한다. 재료의 특 성을 비교하기 위하여 ASTM 규정에 따라 인장시험과 압축시험을 수행하고 반복하중에 대한 저항을 확인하기 위하여 인장반복시험과 압축반복시험을 수행한다. 이때 측정된 응력, 영구변형 등을 그래프로 도식화하고 강재와 비교분석을 진행하였다.

In the seismic evaluation of underground utility tunnels, selecting an analytical method is critical to estimating reasonable seismic responses. In simplified pseudo-static analysis methods widely applied to typical seismic design and evaluation of underground tunnels in practice, it is essential to check whether the methods provide valid results for cut-and-cover tunnels buried in shallow to medium depth. The differences between the two simplified pseudo-static methods are discussed in this study, and the analysis results are compared to those obtained from FLAC models. In addition to the analysis methods, seismic site classification, overburden soil depth, and sectional configuration are considered variables to examine their effects on the seismic response of underground utility tunnels. Based on the analysis results, the characteristics derived from the concepts and details of each simplified model are discussed. Also, general observations are made for the application of simplified analysis methods.

선박을 통해 유입되는 마약의 단속 건수와 사례는 그리 많다고 하진 않을 것 이나, 단 한 번의 운반으로도 상당한 양의 마약이 유통될 수 있어 막대한 사회· 경제적 파급력을 초래할 수 있다. 통상 선박을 통해 유입되는 마약의 단속은 마약을 운반 중이라는 혐의가 있 다는 첩보 아래 당해 선박이 우리나라의 영해에 진입한 경우에 관할권을 행사 함으로써 행해진다. 그러나 선박을 통한 마약 운송이 지능화됨에 따라 이른바 ‘던지기 수법’이라는 해상에서 연안국의 관할권이 닿지 않는 영해 이원의 해상 에 마약류를 띄워놓고 거래자가 수거하는 방식이 발생하고 있으며, 이 같은 방 식은 특히 대한해협과 같이 영해 폭이 좁은 공간에서 사용될 여지가 있다. 이같이 지능화되는 해상 마약 거래를 차단하기 위해선, 국제사회와의 적극적 협력을 통해 외국선박에 대한 임검 등이 효과적으로 시행될 수 있어야 하며, 동시에 선주와 선원 등 선박 관계자의 세심한 주의가 필요하다. 그러나 외국선 박의 단속에 관한 국제법은 특히 단속 절차적 측면에서 특별한 요건을 요구하 고 있다. 따라서 해상 마약 단속에 관한 법률의 검토와 개선이 필요하며, 국내 법의 개선에는 국제법적인 고려가 선행되어야 한다. 미국의 경우 국제법을 고려함과 동시에 다소 도발적으로, 혹은 선진적으로 보이는 방법으로 국내법을 정비하여 마약 단속을 위해 노력 중이다. 이에 이 논문은 현행 마약 단속에 관한 국제법의 검토와 함께, 미국의 실행 에서 시사점을 도출하여 국내법적 개선 방안을 제시하고자 하였다. 연구 결과, 국제법상 국가의 관할권(보호주의적 관할권)을 적극적으로 활용 하고, 마약 혐의를 받는 선주와 선박이 취해야 할 행동을 강제화하고, 추가로 외교적 노력을 통해 적극적인 마약 단속을 수행할 방안을 제시하였다.

Background: Child care center teachers are exposed to musculoskeletal injuries caused by repetitive movements at low heights due to the nature of their jobs. Self-myofascial release (SMFR) improves flexibility, pain, and functional performance. Pectoralis minor self-stretching (PMSS) improves muscle flexibility and postural alignment. PMSS has been commonly used to correct a rounded shoulder posture (RSP). Objectives: To examine the shoulder height, muscle tone, muscle stiffness, and muscle elasticity for women child care center teachers with RSP. Design: Randomized study. Methods: The participants were 20 women child care center teachers with RSP. They were randomly assigned two groups: SMFR group (n=10) and PMSS group (n=10). They performed each exercise for 20 min, 3 times a week for 4 weeks. They measured shoulder height, muscle tone, stiffness, and elasticity of upper trapezius before and after exercise. Results: In the shoulder height, there was no significant difference between two groups. There were significant decreases within both groups. In the muscle tone, stiffness, and elasticity, there was no significant difference between two groups and within two groups. Conclusion: SMFR using a hard massage ball and PMSS have a positive effect on posture correction for child care center teacher with RSP.

Background: Treadmill training is an effective intervention method for improving the walking ability of stroke patients, and taping is effective for stabilizing joints. However, taping interventions have not been implemented during treadmill training. Objectives: To examine whether treadmill training with an elastic tape or treadmill training with a non-elastic tape could be more effective in stroke patients. Design: A single blinded, randomized, controlled, comparative study. Methods: 22 stroke patients were randomly allocated to two groups: the elastic group (treadmill gait training with ankle elastic tape on the paretic side) or the non-elastic group (treadmill gait training with non-elastic tape on the paretic side). All participants performed 60 min of comprehensive rehabilitation therapy and treadmill training with an elastic tape or non-elastic tape for 20 min. Results: 10-meter walk test and timed up-and-go test results after training differed significantly from baseline in both groups (P<.05), but significantly larger gains were observed in the elastic group (10-meter walk test, -17.1%; timed up-and-go test, -18.49%; P<.05, respectively). Conclusion: Treadmill gait training with elastic tape on the affected ankle joint might be more effective at improving the walking and balancing abilities of stroke patients.

This study comprehensively investigates three types of graphite materials as potential anodes for potassium-ion batteries. Natural graphite, artificial carbon-coated graphite, and mesocarbon microbeads (MCMB) are examined for their structural characteristics and electrochemical performances. Structural analyses, including HRTEM, XRD, Raman spectroscopy, and laser particle size measurements, reveal distinct features in each graphite type. XRD spectra confirm that all graphites are composed of pure carbon, with high crystallinity and varying crystal sizes. Raman spectroscopy indicates differences in disorder levels, with artificial carbon-coated graphite exhibiting the highest disorder, attributed to its outer carbon coating. Ex-situ Raman and HRTEM techniques on the electrodes reveal their distinct electrochemical behaviors. MCMB stands out with superior stability and capacity retention during prolonged cycling, attributed to its unique spherical particle structure facilitating potassium-ion diffusion. The study suggests that MCMB holds promise for potassium-ion full batteries. In addition, artificial carbon-coated graphite, despite challenges in hindering potassium-ion diffusion, may find applications in commercial potassium-ion battery anodes with suitable coatings. The research contributes valuable insights into potassiumion battery anode materials, offering a significant extension to the current understanding of graphite-based electrode performance.

In response to the growing demand for high-performance lithium-ion batteries, this study investigates the crucial role of different carbon sources in enhancing the electrochemical performance of lithium iron phosphate ( LiFePO4) cathode materials. Lithium iron phosphate ( LiFePO4) suffers from drawbacks, such as low electronic conductivity and low lithium-ion diffusion coefficient, which hinder its industrial development. Carbon is a common surface coating material for LiFePO4, and the source, coating method, coating amount, and incorporation method of carbon have a significant impact on the performance of LiFePO4 materials. In this work, iron phosphate was used as the iron and phosphorus source, and lithium carbonate was used as the lithium source. Glucose, phenolic resin, ascorbic acid, and starch were employed as carbon sources. Ethanol was utilized as a dispersing agent, and ball milling was employed to obtain the LiFePO4 precursor. Carbon-coated LiFePO4 cathode materials were synthesized using the carbothermal reduction method, and the effects of different carbon sources on the structure and electrochemical performance of LiFePO4 materials were systematically investigated. The results showed that, compared to other carbon sources, LiFePO4 prepared with glucose as the carbon source not only had a higher discharge specific capacity but also better rate cycle performance. Within a voltage range of 2.5–4.2 V, the initial discharge specific capacities at 0.1, 0.5, and 1 C rates were 154.6, 145.6, and 137.6 mAh/g, respectively. After 20 cycles at a 1 C rate, the capacity retention rate was 98.7%, demonstrating excellent electrochemical performance.

목적: 본 연구는 4가지 다른 프리즘 종류와 크기에 따른 측정 시 발생하는 오차를 수치화하고, 특히 낱개 프리즘을 사용할 때 발생하는 기울임에 의한 오차를 비교하고자 한다. 방법 : 각 4가지 유형의 프리즘 렌즈 수평 프리즘 바(H), 수직 프리즘 바(V), 낱개 프리즘(I), 프레넬 프리즘(F) 에 대해 4개씩 제품을 준비하여 실험을 진행했다. 1 m 거리에서 총 4번 같은 방향으로 측정했으며, H, V, I는 7가 지 프리즘(Δ), 프레넬 프리즘은 3가지 프리즘 크기를 측정하여 발생하는 오차를 비교하였다. 또한 낱개 프리즘의 경우 방향 오차로 인한 오차를 비교하기 위해 1, 3 및 5도를 측정하였고, 수평 방향으로 8가지 프리즘, 수직 방향 으로 6가지 프리즘 크기에 따른 오차를 비교했다. 결과 : 수평 방향에서 프리즘 렌즈를 측정한 결과, H와 I가 가장 오차가 적었으며 두 렌즈 간 차이는 크지 않았 다. F는 12 Δ에서 유의한 오차가 나타났으며(p<0.010), 20 Δ에서 V의 오차가 높아져 F와의 차이가 없었다. 수직 방향에서는 프리즘 크기가 작을수록 H와 V 사이에 차이가 없었으나, 16 및 20 Δ부터 H와 V에서 유의한 오차가 나타났다(p<0.010). I를 수평 및 수직 방향으로 3가지 각도로 기울였을 때, 2 Δ에서는 수평 및 수직 방향 모두에서 차이가 없었다. 그러나 4~20 Δ까지 프리즘 크기가 커질수록 수평 및 수직 방향 모두에서 기울기가 증가함에 따라 유의한 차이가 나타났다(p<0.010). 결론 : 본 연구의 결과에 따르면, 프레넬 프리즘에서 가장 많은 오차가 발생한 반면, 낱개 프리즘에서 가장 적은 오차가 나타났다. 프리즘 바는 수평 및 수직 방향으로 나누어져 있어 사용 목적에 맞게 정확히 사용해야 한다. 프 리즘 크기가 커질수록 측정 각도를 주의해야 하며, 임상에서는 오차가 적은 낱개 프리즘을 사용하는 것을 권장 한다.

Researchers have examined how individuals' preferred ways of comparing achievements differ according to their mindset. However, studies investigating the concomitant impact of such differences on individuals' happiness are relatively scant. Using a variety of scenarios, the present study examined how fixed-mindset and growth-mindset individuals' different achievement-comparison styles (more than others, less than others, better than before, and worse than before) affected their subjective happiness. A total of 880 participants were recruited. Fixed-mindset individuals felt happy when they felt they achieved more than others and unhappy when they felt the opposite, but were not influenced significantly when their achievement was better or worse than before. Conversely, growth-mindset individuals felt happy when their achievement was better than before but unhappy when it was the opposite, without being influenced significantly by achieving more or less than others. This study examined mindset, achievement comparison, and subjective happiness comprehensively, which, to date, have only been examined independently.

Drug-induced liver injury (DILI) is considered to be a significant cause of drug wastage. To mitigate clinical DILI risks, assessing drugs using human liver models is crucial since animal studies may fall short due to species-specific liver pathway variations. Cell-based preclinical hepatotoxicity testing is often pertinent. In the present study, cells from a human liver cancer line (HepG2 and HepaRG) were cultured in both formats of 2D and 3D spheroids to explore their responses to drugs. Liver-specific marker expressions across cell lines and culture formats were also examined to assess disparities in DILI marker expressions. After treating each cell with the drugs, cytotoxicity and liver injury markers aspartate aminotransferase and alanine aminotransferase were increased. In addition, liver specific markers albumin and urea decreased in a drug concentration-dependent manner. These findings were consistent with drug sensitivity. Additionally, mRNA expression levels of cytochrome P450 enzymes (CYPs) involved in hepatocellular drug metabolism were compared following treatment with enzyme inducers. CYP1A2 and CYP2C9 were not epxressed in HepG2 cells. HepaRG cells exhibited significantly increased expression of CYP1A2, 2C9, and 3A4 post-treatment. Notably, enzyme expression was notably higher in 3D cultures than in 2D cultures. Collectively, these findings suggest that HepaRG cells and 3D cultures hold promise for evaluating DILI during early-stage drug development.

This study evaluates the analytical performance of a newly developed miniaturized disposable U-tube for an automated blood viscometer and compares it to conventional viscometers. Whole blood viscosity (WBV), essential for circulatory function, exhibits non-Newtonian behavior, posing challenges for measurement at low shear rates. The blood viscometer, based on a scanning capillary tube method, used disposable U-tubes to measure viscosities across a shear rate range of 1s⁻¹ to 1,000s⁻¹. Precision evaluation showed stable coefficients of variation (CV) across different viscosity levels. Repeatability assessment indicated consistent CV values, demonstrating the reliability of the device. The agreement with the LV-III Brookfield viscometer and MCR 92 Rheometer was analyzed using Bland-Altman plots, which revealed minor systematic biases and consistent differences across the measurement range. Correlation analysis using Passing-Bablok regression showed high correlation coefficients (R > 0.96) with regression slopes close to 1. The newly developed miniaturized disposable U-tube exhibits excellent precision, reliable repeatability, and high correlation with established methods, enhancing laboratory productivity and offering potential for clinical applications. Further studies with human blood samples are recommended to confirm its clinical applicability.

Wall-embedded ventilators, which are commonly used for ventilation of buildings, greatly damage the aesthetics of the building due to pollutants such as dust and grease sticking to the fan and gaps of the ventilator as the period of use increases. For this aesthetic reason, it is often installed in a place that is not easily visible to people, and if the ventilation fan is not properly arranged and installed, it is difficult to maintain indoor air in an optimal state. In this study, the effect of the arrangement of ventilators on indoor ventilation performance was investigated. Comparisons were made between the case where three ventilators were concentrated and the case where they were spaced apart at regular intervals. It was found that the ventilation performance was different depending on the location where the ventilators were installed.

In the past, aviation technology developed from wood to alloys to composite materials. Propellers have also evolved from wood to composite materials for modern small aircraft. In this context, research is needed on a three-blade composite propeller based on the Rotax 912 engine, which is widely used in Korea. In this study, the goal is to select the optimal propeller pitch angle by investigating noise changes according to changes in blade angle and engine 4000RPM of three types of three-blade propellers different from each propeller manufacturer. By comparing the noise of the three types of propellers most commonly used in Korea and suggesting the minimum noise blade angle for each propeller, we aim to help aircraft operators select propellers and resolve noise complaints around airfields.

This study focused on improving the solubility of silodosin, a drug poorly soluble in water, by utilizing solid dispersions. Three types of dispersions were examined and compared against the drug powder: surface-attached (SA), solvent-wetted (SW), and solvent-evaporated (SE). Polyvinyl alcohol (PVA) was identified as the most effective polymer in enhancing solubility. These dispersions were prepared using spray-drying techniques with silodosin and PVA as the polymer, employing solvents such as water, ethanol, and a water-acetone mix. The physicochemical properties and solubility of the dispersions were evaluated. The surface-attached dispersions featured the polymer on a crystalline drug surface, the solvent-wetted dispersions had the amorphous drug on the polymer, and the solvent-evaporated dispersions produced nearly round particles with both components amorphous. Testing revealed that the order of improved solubility was: solvent-evaporated, solvent-wetted, and surface-attached. The results demonstrated that the preparation method of the solid dispersions significantly impacted their physicochemical properties and solubility enhancement.

There are two primary sludge drying methods such as the direct heating microwave method and the indirect heating steam one. In this study, the drying treatment facility at sewage treatment plant A applied both of these drying methods. The research aimed to investigate the optimal operation approach for the drying facility, considering the input sludge and the moisture content data after the drying process. Moisture content and removal rate data were executed at the research facility from January 2016 to December 2018. First, the microwave, a direct heating drying method, performed intensive drying only on the outer surface of the sludge by directly applying heat to the sludge using far infrared rays, so effective sludge drying was not achieved. On the other hand, the steam method of the indirect heating method used steam from a gas boiler to maximize the utilization of the heat transfer area and reduce energy of the dryer, resulting in an effective sludge drying efficiency. The sludge moisture content brought into the sludge drying facility was about 80%, but the moisture content of the sludge that went through the drying facility was less than 10% of the design standard. Therefore, the steam method of the indirect heating method is more effective than the microwave method of the previous direct heating method and is more effective for maintenance It has proven that it is an efficient method of operating construction facilities.

This study aims to compare six observational methods for assessing arm- and hand-intensive tasks, based on literature review. The comparison was conducted in viewpoints of body regions, force/external load, motion repetition, other factors including static posture, coupling, duration/break, pace, temperature, precision task, and final risk or exposure level. The number of risk factors assessed was more, and assessment procedure was more complex than the observational methods for assessing whole-body postural loads such as Ovako Working Posture Analysis System(OWAS), Rapid Upper Limb Assessment(RULA), and Rapid Entire Body Assessment(REBA). Due to these, the intra- and inter-reliabilities were not high. A past study showed that while Hand Arm Risk Assessment Method(HARM) identified the smallest proportion of the work tasks as high risk, Strain Index(SI) and Quick Exposure Check(QEC) hand/wrist were the most rigorous with classifying most work tasks as high risk. This study showed that depending on the observational technique compared, the evaluation factors, risk or exposure level, and evaluation results were different, making it necessary to select a technique appropriate for the characteristics of the work being assessed.

최근 우리나라에서 벌채와 산사태의 연관성에 대한 논란이나 숲가꾸기의 효과에 대한 의문이 제기되면서 산림관리에 대한 중요성이 더욱 강조되고 있다. 그러나 국내에서 이를 뒷받침하기 위한 정량적 평가자료는 부족한 실정이다. 이러한 배경을 바탕으로 이 연구는 수목 뿌리의 토양보강 효과에 대한 정량적 평가를 위한 연구주제와 방향성을 제언하고자 계량서지학적 분석을 이용하여 최근 30년(1990-2019)간의 국제·국내 관련 논문의 연구동 향을 비교·분석하였다. 그 결과, 국제 연구논문의 게재 편수는 증가 추세를 보였으며, 학문 분야와 연구영역이 다양화되어 있음이 확인되었다. 연구영역의 경우 수목 뿌리의 토양보강 메커니즘 규명(제1연구영역), 임분 조건에 따른 토양보강 효과 추정(제2연구영역), 수목 뿌리의 토양보강 효과를 고려한 사면안정성 평가(제3연구영역) 및 계안안정성 평가(제4연구영역)로 구분되었다. 이처럼 국외에서는 산사태 방지에 있어 산림생태계의 구조와 기능이 중요한 요소로 인식되었던 것으로 판단되었다. 반면, 국내 학술지는 제1연구영역과 제3연구영역만이 출현하여 상대적으로 기초적인 수준으로 확인되었다. 따라서 기후변화로 다변화되는 산림생태계의 산사태 방지 효과에 대한 정량적 평가를 위해서는 향후 다양한 수종뿐만 아니라 생육조건, 교란 이후 토양보강 효과의 변화를 규명하기 위한 제2연구영역과 관련된 연구가 활발히 수행되어야 할 필요가 있을 것으로 판단되었다.