Following the implementation of the Act on the Prevention of Light Pollution Due to Artificial Lighting in 2013, local governments designated lighting environment management zones and conducted assessments of the impacts of light pollution on the environment to ensure compliance with acceptable light emission standards. In addition, according to the Act on the Prevention of Light Pollution Due to Artificial Lighting, local governments conduct and manage light pollution assessments every three years. However, measuring and analyzing during nighttime requires a significant amount of time and labor. Therefore, this research aims to improve the current light pollution environmental impact assessment method by utilizing aerial information from satellite data and establishing a database of light pollution assessment methods, thereby laying the foundation for light pollution management. In this study, a reference light source was installed on the ground, and the luminance measurements of the installed reference light source and the advertising light sources on-site were analyzed to derive brightness values for ground light sources using the optical band (R, G, B) values from aerial information derived from satellite images. The analysis produced predictive equations for light pollution from upward lighting and general advertising lighting. When these equations were applied to residential and commercial areas in the lighting environment management area, the results indicated that the predicted rooftop upward lighting prediction brightness exceeded the acceptable standard of light emission of 800 cd/m2 in residential areas, and the advertisement lighting prediction brightness exceeded the standard of 1,000 cd/m2 in commercial areas.

In this study, in order to develop an eco-friendly filtration method that considers the health and safety of the aquatic ecosystem by differentiating it from chemical methods (coagulants, oxidants, etc.), which are mainly used as methods for managing the removal of algae in the algal bloom stage, an effective separation membrane for algae removal was reviewed, an appropriate technology was proposed through field application, and the effect of algae removal was evaluated. The membrane used was applied in the field by constructing an optimal technology through auxiliary facilities with an immersion tubular membrane and a pressurized tubular membrane resistant to adhesive pollutants and algae. As a result, the strong characteristics of Fouling (blocking) by adhesive algae were confirmed, and the effect of removing algae and particulate matter in the immersion type tubular membrane was 99% chlorophyll-a (Chl-a), 99.2% suspended solid (SS), and 96.7% of pressurized tubular membranes, showing excellent effects in removing algae and particulate organic matter. In addition, as a result of field application to eutrophic reservoirs where high-density algae are distributed, it was confirmed that stable operation of algae was possible during the process of filtering, separation, and concentration.

This study developed an unmanned autonomous moving algae collection device (HAMA-bot) to remove high-density algae concentrated in the waterfront of urban agricultural reservoirs, and analyzed the effect of algae removal after field application to medium-sized urban reservoir. The algae reduction effect (Chl-a) of the study site in the reservoir by the HAMA-bot operation showed an average 18.5% higher in the treatment area compared to the control area before operation, while the average reduction of 24% in the treatment area after operation. In addition, the Chl-a removal rate, which directly analyzed the influent and effluent of HAMA-bot, showed a very high level with an average of 96.9% (94.7~99.2%). Currently, it is optimized for urban reservoirs and manufactured on a small scale, but it is a useful tool that can be applied on a large scale to large dams and rivers, and it is considered that the field applicability would be improved with the optimized scale.

This study aims to implement an integrated control system for a micro drill bit grinding machine to increase the processing stability and production efficiency of the equipment. The system consists of a WTGM mechanism, an environmental measurement sensor (RMU device), a control server, and a control client, and collects production statistics and alarm information in real time to enable central monitoring and statistical analysis. Through the control system, managers can check data and solve problems anytime and anywhere, thereby increasing the stability and efficiency of the production process. As a result of the experiment, it showed excellent performance in all evaluation items such as alarm occurrence time, notification time, and event operation time through temperature and humidity sensors, and contributed to productivity improvement through immediate response through e-mail and SNS notification. In conclusion, the implemented system optimizes the operating rate and inventory management of the equipment through real-time monitoring and yield analysis, and it is expected to improve system performance as it can be used as learning material for pattern analysis and deep learning algorithms in the future.

본 연구는 RC(철근콘크리트) 기둥과 FRP 콘크리트 기둥의 압축성능을 P-M 상관도를 통해 비교, 분석하였으며, 특히 콘크리 트 압축강도, 보강비, FRP의 탄성계수 변화에 따른 기둥의 거동 특성을 분석하였다. 연구 결과, 고강도 콘크리트(40MPa 이상) 사용 시 FRP 보강 기둥의 성능이 RC 기둥을 상회하며, 균형파괴점이 압축영역으로 이동하여 안정성이 향상됨을 확인하였다. 보강비는 0.010∼ 0.015 범위에서 최적 성능을 발휘하며, 과도한 보강은 오히려 취성파괴 위험을 증가시킬 수 있음을 확인하였다. FRP 물성 선택에 있어 낮은 파괴변형률과 적절한 탄성계수를 가진 재료를 사용하여 균형파괴점을 압축영역에 위치시키는 것이 중요함을 제시하였다. 본 연구 는 FRP 보강 기둥 설계 시 콘크리트 강도, 보강비, FRP 물성을 종합적으로 고려하여 압축성능을 최적화하고 안정성을 확보할 수 있는 방안을 제시하였다. 이러한 결과는 FRP 보강 콘크리트 기둥의 효과적인 설계 및 성능 향상에 기여할 것으로 기대된다.

In this paper, we aim to improve the output quality of a food 3D printer through optimized component design and implementation. Existing 3D printers produce customized outputs according to consumer needs, but have problems with output speed and poor quality. In this paper, we aim to solve this problem through optimized design of unit parts such as the extruder, nozzle, guide, and external case. Fusion 360 was used for element design, and in the performance evaluation of the implemented system, the average precision was 0.06mm, which is higher than the non-repeatable precision of ±0.1㎜ of other products, and the feed speed of the existing system was evaluated to be more than twice as fast, from 70mm/s to 140mm/s. In the future, we plan to continuously research output elements that can produce texture and color and device control methods for convenience.

The Occupational Safety and Health Act (OSHA) aims to maintain and promote the safety and health of workers. Additionally, violations of the act can result in imprisonment or fines, depending on the severity of the offense. This study examines whether the severity of OSHA violations is proportional to the size of the fines imposed. There are 120 items subject to fines, with penalties ranging from a minimum of 50,000 won to a maximum of 30 million won. To assess the severity of these items, pairwise comparisons were conducted, and the results were expressed numerically. In summary, no significant correlation was found between the severity of violations and the amount of the fines. Therefore, this study proposes calculating fines based on the severity of violations. In many small companies, resources (e.g., budget and manpower) are limited. Thus, greater attentions tend to be directed toward addressing items with higher fines. Consequently, aligning the severity of legal violations with the size of the fines may contribute to improving the industrial safety.

췌장암은 진단 시점에 진행된 상태인 경우가 많으며, 이때 항암화학요법이 주요 치료법으로 사용된다. 지난 10여 년간 새 로 운 항 암 화 학 요 법 의 도 입 으 로 전 체 생 존 기 간 이 연장되었음에도 진행된 췌장암의 중앙 생존 기간은 여전히 1년 미만이다. 그러나 임상현장에서는 때때로 진행된 췌장암 환자 중 장기 생존자를 경험하게 되며, 이러한 사례를 분석하면 췌장암에 대한 이해를 높이고 치료 방침 개선에 중요한 실마리를 얻는데 도움이 될 것이다. 우리는 약 5년 동안 생존한 전이성 췌장암 환자를 경험하였고 이 환자의 첫 진단 당시와 진단 후 57개월에 얻은 조직의 단일세포 전사체 분석 결과 비교를 통해 췌장암 진행에 따른 종양 면역 미세환경 변화를 확인하였기에 보고한다.

담관암의 유일한 치료 방법은 수술로, 수술 가능성 평가가 진단 과정에 있어 매우 중요하다. 처음 진단 당시에는 원격 전이가 확인되지 않아 수술적 치료를 계획하던 중 다발성의 폐결절이 새롭게 확인되었던 원위부 총담관암 증례를 문헌고찰과 함께 보고한다. 원발 부위의 원위부 총담관암의 크기 변화는 없어 폐 전이 외의 감별진단이 필요하다고 판단하였다. 최근 COVID-19 감염력이 있던 증례로 수술 생검 결과상 최종적으로 폐 크립토코코스증으로 진단되었다.

Executive safety leadership is essential to prevent accidents in the workplace. However, will safety be secured by emphasizing only executive safety leadership to workers? In this study, the impact of executive safety leadership on the workplace hazard level was analyzed by adding the supervisor's safety role as a mediating variable. This paper shows that executive safety leadership has no direct effect on workplace hazard levels. However, executive safety leadership was found to have a significant impact on the supervisor safety role, and the supervisor safety role was found to lower the hazard levels in the workplace. In summary, executive safety leadership was found to reduce the hazard levels in the workplace through the full mediating effect of the supervisor safety role. Based on these research results, this study seeks to present the following recommendations to the government and management: The government should ensure that a workplace safety and health system is established by strengthening the effects of other mediating factors, such as strengthening the role of supervisors who are actually responsible for workplace safety and health. Executives must grant supervisors actual authority and responsibility to properly perform their safety roles and establish personnel and performance evaluation systems.

본 연구는 보강 콘크리트로 철근 대신 복합재료를 사용한 구조물의 설계에 대하여 다양한 파라미터 연구를 수행하여 철근콘크리트 대비 강점을 비교, 분석하였다. FRP 콘크리트는 ACI 440.1R-15를 적 용하였으며, 철근콘크리트 설계는 KDS 14(2021)의 최신 규정을 적용하여 다양한 파라미터 연구를 수 행하였다. 파라미터 변수로 콘크리트 밑단에서 철근의 중심까지의 거리, 보강량, FRP의 탄성계수 및 극한 변형률의 4개로 설정하여 다음과 같은 결론을 얻었다. (1) FRP의 탄성계수와 극한 변형률이 클 수록 FRP 콘크리트의 휨성능이 우수하지만, 극한 응력이 동일할 때 극한 변형률보다 탄성계수를 크게 하는 것이 유리하며, 보강량이 작을수록 유리한 것으로 분석되었다. (2) FRP 콘크리트가 인장지배 단 면이나 변화구간 일 때 극한 변형률 증가에 휨성능이 비례해서 증가하지만 압축지배 단면일 경우에는 극한 변형률이 증가해도 휨성능은 증가하지 않는다. (3) FRP 콘크리트의 휨성능은 FRP의 탄성계수와 극한 변형률을 적절하게 조절하여 선택함으로서 최적의 성능을 나타낼 수 있다. (4) 또한, FRP 콘크리 트는 최소 피복두께가 필요하지 않아 추가적인 휨성능이 17~33% 증진 효과가 나타났다.

Garlic mustard (Alliaria petiolata) is a species that has devastated the United States and Canada. It is known to play a role in destroying the ecosystem. In this study, the domestic distribution of garlic mustard was confirmed and a detailed distribution map was created for the Samcheok region, where the largest population has been established in South Korea. This study investigated the growth environment, life cycle, and population dynamics of the species in the Samcheok region. Garlic mustard was found in a total of 301 locations in Samcheok, with a total distribution area of 2,957 square meters. Annual plants germinated in mid-April, overwintered in rosette form, underwent vegetative growth from April 10 to April 24 the following year, and flowered from April 24 to May 7. Individuals producing seeds began to die off from June. Both annual and biennial individuals showed a trend of increasing and then decreasing in number around April 27 (118 days). Garlic mustard grew well under favorable light conditions in early spring. They showed less growth on leaf litter, short distance from roads, lower altitude, deciduous broad-leaved forest of middle and lower parts of the slope and forest edge. Without proper control measures in the Samcheok region, it is likely to spread more rapidly in deciduous broad-leaved forests along hiking trails in the Galyasan Mountains. In particular, it is more likely to extend to oak community where light enters the site during flowering than to pine community where there is less light in the site.