본 연구는 Van Meter & Van Horn의 정책 집행 시스템 모델을 이론 적 틀로 삼아, C대학을 사례로 중국 대학생 혁신창업교육 정책의 집행 효과에 나타나는 차이를 탐구하였다. 연구방법으로는 사례연구를 적용하 였고, 첫째, 문헌 분석을 통해 중국의 관련 정책과 C대학의 정책 집행 문서를 정리함으로써, 이론적 기반과 주요 영향 요인을 도출하였다. 둘 째, 심층 인터뷰를 하여 C대학의 정책 집행 현황을 조사하고, 정책 집행 자, 교수, 학생들의 피드백을 수집함으로써 정책 집행 과정에서 나타나는 핵심 문제를 분석하였다. 연구결과, 중국 대학생 혁신창업교육 정책의 집 행에는 정책 개념의 모호성, 자원의 부족, 다중 조직 간 협력의 어려움, 경직된 행정 체계, 낮은 사회 참여도, 집행자의 소극적 태도 등이 주요 저해 요인으로 작용하고 있음이 확인되었다. 이에 본 연구는 정책 효과 제고를 위해 정책 개념의 명확화, 재정 지원 제도의 구축, 조직 구조의 최적화, 데이터 플랫폼의 마련, 자원 통합 시스템 구축, 교사와 학생 중 심의 실행 방안 등 여섯 가지 개선 방향을 제안하였다. 이러한 연구는 Van Meter & Van Horn 모델의 적용 가능성과 정책 집행에 미치는 구 체적 영향을 실증적으로 분석함으로써, 향후 정책 수립과 집행 과정에 실질적 시사점을 제공한다.
This study analyzed the changes in sodium content across different types of kimchi over various storage periods, distinguishing between solids and seasoning (liquid), to better estimate actual sodium intake and improve the food composition databases. Six types (baechu-kimchi, oi-sobagi, buchu-kimchi, baek-kimchi, dongchimi, and nabak-kimchi) were analyzed using ICP-AES. The results were compared with salinometer readings, food composition databases, and nutrition labels from commercial products. Statistical analyses included the Mann-Whitney U test and the Kruskal-Wallis test (=0.05). The findings showed that the seasoning had significantly higher sodium content than the solids and, except for baechu-kimchi and nabak-kimchi, accounted for more than 50% of the total sodium content. Sodium content varied across kimchi types and changed over storage time. Additionally, sodium content measured by ICP-AES significantly differed from those in the food composition databases and commercial nutrition labels, which often over or under-estimated values. Moreover, sodium content in commercial kimchi products exhibited up to a 581-fold difference between the minimum and maximum values. These results suggest that current databases and labeling systems, which do not distinguish between solids and seasoning, may misrepresent the actual sodium intake. Further research and regulatory measures are needed to improve sodium estimation and consumer guidance.
기후변화로 인해 폭염 기간 증가, 하절기 극고온, 혹한기 극저온 현상이 두드러지면서 도로포장에 소성변형과 포트홀이 빈번하게 발생할 위험이 커지고 있다. 이로 인해 SMA(Stone Mastic Asphalt) 포장의 공용성능을 유지하기가 어렵다. SMA 포장은 골재 간 맞물림이 뛰어나 중차량 교통량이 많은 도로에서 내구성을 높이는 데 유리하지만, 이를 효과적으 로 활용하기 위해서는 혼합물 배합설계와 시공과정에서 다짐 품질을 엄격히 관리해야 한다. 국내 지침에서는 점도가 높은 개질 아스팔트 바인더(6% 이상)를 사용하는 SMA 혼합물이 다짐 시 타이어에 달라붙을 가능성이 커 타이어 롤러의 사용을 제한하고 있다. 그러나 적절한 부착방지제 사용, 타이어 예열, 시공 온도 확보 등을 통해 혼합물 부착 문제가 완화되고, 다짐도와 초기 공용성능을 높인 사례가 점차 보고되고 있다. 이는 타이어 롤러 특유 의 ‘반죽(kneading) 효과’로 인해 기존 철륜(머캐덤·탄뎀) 롤러 대비 하부층까지 균질하게 다져줄 수 있기 때문이다. 따라 서 이상기후 환경에서 SMA 포장의 균열·소성변형을 줄이기 위해서는 다짐도 증가에 따른 적절한 아스팔트 바인더 함량 결정이 필요하다. 더불어 시공 장비 및 혼합물 관리가 유기적으로 개선된다면 SMA 포장의 특성을 살린 적정능력이 발 휘될 수 있을 것이다. 본 연구에서는 SMA 포장 적정능력을 발휘하기 위한 기초연구를 수행하였다. 이를 위해 SMA 포장 시공 시 타이어 롤 러 장비 적용 효과, 혼합물 부착 방지 기술, 아스팔트 바인더 함량 조정 등을 국내·외 시공 사례와 문헌조사를 통해 고찰 하였다. 또한 타이어 롤러의 현장 적용성을 파악하기 위해 시험포장 구간에 대해 소형낙하하중시험(LFWD)을 실시하고, 표면처짐량과 역산 탄성계수를 산출하여 시공 품질 개선 가능성을 확인하였다.
본 연구의 목적은 ‘아동학대 예방 및 피해아동 보호 조례’ 비교·분석을 통해 아동학대를 예방하고 피해아동을 보호하기 위한 조례 개정 방안을 제시하는 것이다. 이를 위해 충청북도 및 6개 기초자치단체 조례를 사회 복지조례의 내용적 체계 비교 분석틀에 기초하여 비교·분석하였다. 분석 결과, 충청북도 조례는 적용대상, 재정부담, 벌칙 구성요소에서, 충주시 조례는 권리성, 적용대상, 전달체계, 인력 구성요소에서 가장 체계적이었 다. 조례 개정 방안으로 학대피해아동쉼터 운영 조항을 ‘지정’이 아닌 ‘운영’으로 개정, 단체장의 책무로써 재정적 지원 명시 및 예산 지원 강 행규정으로 변경, 인력의 전문성 강화를 위한 아동학대 전담공무원 임용 및 필수 보직기간 설정을 제시하였다.
This study aims to reduce the use of chloride-based deicers by analyzing their residual quantities on road surfaces. The freezing conditions of road surfaces were quantitatively defined using needles of consistent weight and diameter, and indoor experiments were conducted to observe changes in surface conditions caused by residual deicers under various temperatures. To validate the equipment, a deicer currently used in Korea was applied to granite plates, and the correlation between the application rates and salinity measurements obtained using the SOBO3+ device was analyzed. Subsequently, the device was employed to measure salinity changes over time by assessing the variations in residual deicer quantities on roads with different traffic volumes and application rates. To identify issues in current reapplication methods, the deicer was reapplied at 2-h intervals, and the resulting changes in salinity were monitored. Results of laboratory experiments revealed that the interval for surface state changes decreases with the temperature despite increased deicer usage, and that similar surface change patterns are presented at higher (-2 °C, -4 °C) and lower temperatures (-6 °C, -10 °C). Across all temperatures, the coefficient of determination for the surface-change graph is approximately 0.90. Equipment verification shows that 10% of sodium chloride is underestimated, whereas aqueous calcium chloride is accurately measured and no correlation is indicated between measurement accuracy and road surface temperature. Field experiments confirmed that the deicer dispersion rates increases with the traffic volume. Furthermore, the final salinity increases after the reapplication of the deicer, except in cases of high traffic volume, and that repeated applications with reduced spray amounts are more effective than single applications with higher spray amounts under low traffic conditions. Based on the findings obtained, a plan to reduce deicer usage is proposed. Future research should incorporate additional variables that affect deicer loss and surface condition changes to further refine the results.
This study evaluates adhesion strength under various conditions to ensure adhesion performance during asphalt-pavement maintenance. The adhesion performance of a tack coat varies under various conditions. Therefore, to evaluate its curing behavior, several tests, i.e., evaporation residue rate, tracking, tack-lifter, and shear bond strength tests, were conducted based on the type, amount, and curing time of the tack coat.The result of the evaporation residue rate test shows that, except for the SSC tack coat, RSC-4 and modified tack coats require similar curing times, even though the modified tack coats have a lower moisture content. Additionally, based on the evaporation residue rate, the tracking and track-lifter test results show that approximately 75% curing is required to prevent the loss of the tack coat during asphaltpavement maintenance. After maintenance work is completed, the shear bond strength was measured to evaluate the curing properties of the tack coat. The results show that the amount applied, curing degree, and shear bond strength are proportional, whereas the modified tack coat indicate a significant difference in the strength increase rate depending on the curing degree. Additionally, when dust is attached to the surface of the tack coat, the difference in strength exceeds 20%, depending on the attachment ratio.To achieve the best adhesion performance by the tack coat during maintenance work, the loss of the tack coat should be prevented by implementing the exact curing time determined experimentally, regardless of whether the tack coat is modified, and the surface where the tack coat is applied should be cleaned before application.
To analyze the effect of fire in electric-vehicle battery on concrete cement structure. A scenario evaluation was conducted for fire occurrence due to external influences on lithium battery cells used in electric vehicles. Visual inspection was conducted at each stage of the battery fire, and the fire duration and temperature were measured. The battery temperature rise curve and temperature during fire have been examined previously. The stability of a cement structure was evaluated via X-ray diffraction and SEM analyses of the reaction-product changes with respect to temperature. The battery temperature rise curve shows that the battery begins to change at 200 °C–300 °C. However, the general stage of battery damage cannot be readily confirmed from the literature. The current experiment and literature review indicate that battery fire can cause the fire temperature to increase beyond 1000 °C within a few seconds. The reaction product changes structurally in cement from 300 °C or higher. Many voids are generated owing to the decomposition of Ca(OH)2 and C-S-H gel. The temperature of an electric-vehicle fire increases rapidly to 1000 °C or higher within a few seconds. High temperatures change the reaction products in cement structures, thus creating internal voids and cracks and reducing the stability of the structure; therefore, the appropriate countermeasures must be identified.
Occupational therapy aims to restore patients’ functional abilities through rehabilitation, with dressing activities being a critical component in activities of daily living assessments. Clothing is essential for physical protection, psychological stability, and promoting social participation. Despite the significance of dressing activities, research on training apparel incorporating occupational therapy principles remains limited. As a preliminary step in developing apparel for dressing activity training, this study aims to identify essential design elements that facilitate in daily living training and hold potential in occupational therapy. A comprehensive literature review and case analysis were conducted to identify essential clothing design components. The research results are as follows. The design features a pattern with a front-center opening, generous armholes, and ease allowances, along with modular components that enable variable collar and pocket configurations. A designated weight pocket is seamlessly integrated without restricting movement. Fabric selections emphasize human safety, comfort, stability, and durability, providing a soft texture and a broad range of color options within the modular design. Additional details include detachable collar and pocket elements, while trims and accessories are executed with buttons or zippers for closure and utilize Velcro, buckles, buttons, or drawstrings for size adjustments, all available in a variety of colors and sizes. This study highlights the need for modular, userfriendly training apparel that support occupational therapy goals. The findings provide fundamental insights into dressing activity training wear, serving as a foundational resource for future research and clinical applications.
The International Maritime Organization (IMO) is promoting the transition to eco-friendly fuels such as hydrogen and ammonia, with the goal of achieving net-zero greenhouse gas emissions in the shipping sector by 2050. Hydrogen does not emit greenhouse gases, but it must be stored at an extremely low temperature of -253°C when stored as a liquid. 316L stainless steel is mainly used as a tank material to store liquid hydrogen. FCAW (Flux Cored Arc Welding) is known for its excellent weldability with 316L stainless steel, and it is particularly suited for welding thick metals efficiently, making it an ideal choice for storage tank welding. Finite Element Method (FEM) analysis can simulate the thermal and mechanical deformations occurring during welding with high precision, allowing for accurate prediction of deformation patterns and the derivation of optimal welding conditions. This ensures the stability and quality of the structure while reducing costs. In this study, FCAW butt welding was performed on 316L stainless steel, followed by cross-sectional observation and deformation measurement of the weld area. Based on the cross-sectional observation, a 3D FE model was designed, and heat transfer analysis was conducted. Subsequently, thermo-mechanical analysis was carried out to predict welding deformation.
Magnesium alloys, among various non-ferrous metals, are utilized in diverse fields from the automotive industry to aerospace due to their light weight and excellent specific strength. In the previous Part I study, fiber laser BOP experiments were conducted to derive basic welding characteristics and appropriate bu竹 welding conditions. Subsequently, in the Part II experiment, butt welding was performed, and through tensile tests, hardness tests, and cross-sectional observations, it was found that at laser power of 2.0 kW and welding speed of 50 mm/s, 93% of the base metafs tensile strength and 63.4% of its elongation could be achieved. In this Part III experiment, the microstructures of the base metal and the center of the weld were observed in butt-welded specimens. Through this, laser power and welding speed, on the mechanical behavior and microstructure of magnesium alloys were analyzed
Chunyanggyo Bridge is a major bridge located on the access route to the Silla palace in Muncheon (문천), built in the mid-8th century. Based on the excavation report from the Chunyanggyo Bridge site, the findings of this study can be summarized as follows: 1. It can be inferred that water diversion facilities and temporary wooden structures were erected under a strict construction process plan. 2. The installation of railings and eave-like components on the bridge is evident. 3. The structure is designed to divide the span by establishing an intermediate pier, allowing for the assembly of components at intervals of 3 meters. 4. Chunyanggyo Bridge has at least three or more major structural elements along its length. 5. The bridge width was constructed to be narrow, within 6.4 meters, depending on the spacing of the intermediate piers. 6. The Guitile shaped stones (귀틀형 석재) exhibit nine distinct bonding methods, and as they are critical structural materials for Chunyang Bridge, further in-depth research is necessary. 7. The Chinese Zuelbuengyo (절변교) utilizes straight members angled to overcome spans, applying techniques such as joints found in wooden architecture. This serves as a reference in the research aimed at uncovering the original form of Chunyanggyo Bridge. It is believed that the basic structure of at least 3 Zuelbuengyo (절변교) could be realized through the Guitile shaped stones of Chunyanggyo Bridge.
This study aimed to manufacture emulsified asphalt for free-heated asphalt mixtures with high solid contents using the high internal phase ratio (HIPR) technique and utilize it as basic research data by evaluating the basic properties. The optimal emulsifier was selected by considering the physical and chemical properties of the emulsifier used in the emulsified asphalt, and the solid content in the emulsified asphalt was increased using the HIPR technique. Emulsified asphalt was produced with solid contents of 90%, 80%, 70%, and 62% (current standard) in emulsified asphalt, and the basic properties of the emulsified asphalt were evaluated for each content. In addition, a free-heated asphalt mixture for the surface layer was produced by applying the emulsified asphalt produced for each content, and the performance was evaluated based on the quality standard items presented in the current guidelines of the Ministry of Land, Infrastructure and Transport. When utilizing the HIPR technique, we could manufacture up to 90% of the asphalt solid content in the emulsified asphalt; however, applying it to unheated asphalt mixtures because of the increase in viscosity was impossible. We determined that it could be applied up to a maximum solid content of 80%. In addition, in the free-heated asphalt mixture test, the ratio of the air void increased as the solids content increased, but the strength decreased. An examination of the fracture surface after the strength test revealed that it was brown, which is a characteristic color of emulsified asphalt. This was because the curing time became insufficient as the solid content increased, resulting in insufficient time for strength development. To ensure the performance of the free-heated asphalt mixture, we observed that the viscosity of emulsified asphalt with a high solid content should be reduced; securing the curing time accordingly was an important factor, and it was determined that additional research is necessary.
한국도로공사에서는 전 세계적인 기후위기 대응에 동참하고, 탄소중립기본법, 탄소중립 녹색성장 기본계획 등 정부의 탄소중립 정책 에 부응하기 위하여 “생애전주기 친환경 대응체계”를 구축하였으며, 이에 도로포장의 생애주기 동안 발생되는 탄소배출량을 산출하기 위한 생애전주기평가(Life Cycle Assessment, LCA)의 필요성이 점차 대두되고 있다. 한국도로공사에서는 매년 고속도로 포장상태 모니터링 데이터를 활용하여 공용성을 예측함으로써 포장 유지관리 전략에 활용하고 있으나 이는 거시적인 측면에서의 포장 공용성 모델로 고속도로 포장의 형식, 재료, 공법 등을 고려한 미시적 측면에서의 공용성 모델 개발 및 개발 절차 정립이 필요할 것으로 판단된다. 따라서, 본 연구에서는 고속도로 장기공용성 관측구간(Long Term Pavement Performance, LTPP) 데이터베이스(DB)를 활용하여 고속도로 JCP 공용성 모델을 개발하기 위한 기초연구를 수행하였다. 본 연구에서는 포장상태지수(Highway Pavement Condition Index, HPCI), 표면손상(Surface Distress, SD), 종단평탄성(International Roughness Index, IRI)를 종속변수로, 각 구간별 누적 교통 및 기후인자를 독립변수로 설정하여 다양한 교통 및 환경 영향인자에 따 른 고속도로 JCP 공용성을 예측하기 위하여 기술통계분석, 상관분석, 분산분석, 다중회귀분석을 수행하였다. 고속도로 JCP 공용성에 대한 다중회귀분석 결과, HPCI 모델의 수정된 R2이 0.614.로 SD 모델(0.413)이나 IRI 모델(0.317)에 비하여 높은 설명력을 보이는 것으로 나타났으며, 개별 모델의 회귀식은 통계적으로 유의한 것으로 나타났다.