본 연구는 2017년부터 2021년까지 고속도로에서 발생한 약 9,600건의 사고를 분석하여 자율주행 긴급차량의 신속한 대응 능력을 향 상시키고자 하였다. 조사 결과, 2차 사고가 전체 사망자의 16.8%를 차지하며, 이들 중 약 74%가 선행사고와 관련이 있다는 점이 강조 된다. 이러한 통계는 긴급차량의 신속한 대처 능력이 피해를 최소화하는 데 얼마나 중요한지를 보여준다. 연구에서는 사고의 영향권을 정의하고, 이를 기반으로 긴급차량이 보다 안전하고 효율적으로 사고 현장에 접근할 수 있도록 하는 알고리즘을 개발하였다. 실제 교 통사고 데이터를 활용하여 사고 지속 시간과 다양한 변수를 고려한 기초 분석을 실시하였으며, 도로 특성, 사고 종류, 점유 차로 등 여러 요소를 반영하여 대응 기준을 설정했다. 알고리즘은 자율주행 차량이 실시간으로 주변 정보를 수집하고 신속하게 대응 방안을 마련할 수 있도록 설계되었다. 향후 연구에서는 알고리즘의 실제 도로 환경에서의 적용 가능성을 검토하고, 다양한 변수들을 포함한 추가 연구를 통해 성능을 더욱 개선할 계획이다. 이러한 연구 결과는 교통사고로 인한 피해를 줄이는 데 기여하고, 자율주행 기술을 활용하여 2차 사고의 가능성을 감소시키는 데 중요한 역할을 할 것으로 기대된다.

인명 사고, 차량 화재, 자연재해, 돌발상황 등 긴급상황 발생 시 신속한 대응을 위해 영향권을 정확하게 분석하는 것이 필수적이다. 특히 도로망을 중심으로 한 영향권은 해당 도로의 교통량, 통제 차로 수, 사고 처리 시간에 따라 달라지며, 이를 관리하기 위한 대책 이 필요하다. 따라서 본 연구는 향후 도로 관리 대책 및 의사결정을 지원하기 위해 대기행렬이론을 기반으로 긴급상황 영향권을 분석 하였다. 본 연구에서 영향권은 공간적인 개념으로서 사고 발생지점으로부터 해당 도로 진행 방향 기준 후방으로 도로 소통에 영향을 끼치는 거리로 정의하였다. 사고 발생지점, 사고 발생 링크의 교통량, 차로 수 및 통제 차로 수, 사고 발생 및 사고 종료 시점 등의 변수를 입력 데이터로 설정하였고 긴급상황으로 인해 발생하는 대기행렬길이를 파악하기 위해 대기행렬이론을 적용하였다. 돌발상황 정보를 분석하여 사고 지속시간의 범위를 도출하였으며 이를 기반으로 여러 가지 상황별 영향권을 산출하였다. 유스 케이스별 영향권 산출을 통해 교통량, 이용 가능한 차로 수, 사고 지속시간 각각이 영향권과 어떠한 관계가 있는지 확인할 수 있었다. 본 연구에서 설정한 영향권을 통해 실시간 교통 데이터를 활용하여 유사 상황에서의 영향권을 신속히 파악할 수 있다. 이는 교통사고와 같은 긴급 상황 발생 시 신속하고 정확한 영향권 파악으로 현장 대응 및 의사결정 지원 시스템의 효율성을 높이는 데 중요한 역할을 할 것으로 기대된다.

외국인투자유치를 통해서 지역발전과 경제성장을 이루려는 목적으로 도입된 경제자유구역이 2003년 본격적으 로 도입된 지 20년이 넘었다. 그동안 경제자유구역 연구는 주로 정책적인 측면에서 이루어졌다. 경제자유구역에 실제로 투자한 외국인투자가 시각에서 한국의 경제자유구역이 어떻게 받아들여지고 있는가를 정확하게 평가하는 것이 필요하다. 이에 본 연구에서는 인천경제자유구역 송도지구에서 장기간에 걸쳐서 투자와 경영활동을 성공적으 로 수행하고 있는 4개의 외국인투자기업(삼성바이오로직스, 셀트리온, 얀센백신, 아이센스)에 대한 사례분석을 통 해서 경제자유구역에 대한 심도 있는 평가와 경제자유구역 발전을 위한 정책적 시사점을 도출하고 있다. 본 연구 에서는 더닝의 해외직접투자 절충이론 ‘OLI 프레임워크’를 적용하여 사례를 자세히 분석하고, 경제자유구역 관련 정 책적 시사점을 도출하였다. 본 연구 결과 외국인투자가의 다양한 기업특유우위(Ownership specific advantage) 를 확인할 수 있었고, 각 사례 기업이 중요하게 평가한 인천경제자유구역의 다양한 입지특유우위(Location specific advantage)도 파악할 수 있었다. 100% 지분율의 얀센백신 사례에서는 내부화우위(Internalization advantage) 를 확인할 수 있었으며, 소수지분으로 투자한 나머지 사례에서는 한국기업과 파트너가 되어 협력적 투자를 실행한 동기도 확인할 수 있었다. 본 사례연구 결과로 도출된 정책적 시사점은 첫째, 외국인투자유치에서 결정적인 역할을 한 양질의 토지를 확충할 경제자유구역 추가 지정, 둘째, 경제자유구역 내 외국기업 단독 또는 협력 등 다양한 방식의 연구개발 사업에 대한 지원을 확충 등이다.

본 연구는 로즈마리 다단재배 시 근권부 용적이 어린순 생산성에 미치는 영향을 구명하고자 수행되었다. 정아를 제거한 커먼 로즈마리의 중간부 삽수 10cm를 128공 트레이에 삽목 하여 발근시킨 뒤 125, 200, 550, 750, 1,300 및 2,000mL의 용 기에 이식하여 1, 2년생 삽목묘 어린순의 생육특성과 수량성 을 비교하였다. 1년생 로즈마리의 경우 초기 생육(이식 후 30 일)은 용기 550mL 이상에서 처리 간 뚜렷한 차이가 없었으나, 2년생 로즈마리의 경우 용기가 클수록 생육이 비례하는 경향 을 보였다. 1, 2년생 로즈마리의 지하부 생체중은 용기 550mL 에서 7월 25일 조사 시 각각 6.9g, 24.4g, 11월 24일 조사 시 각 각 10.3g, 24.9g으로 가장 낮았고, 용기 750－2,000mL에서 는 처리 간 차이가 보이지 않았다. 반면 지상부 생체중은 1년 생 로즈마리의 경우 용기가 클수록 증가하다가 1,300mL 이 상에서는 통계적 차이가 없었으며, 2년생 로즈마리 역시 용기 가 클수록 생체중이 유의하게 높았다. 어린순 품질은 1년생 로 즈마리의 경우 용기 2,000mL에서 가장 우수하였으나, 2년생 로즈마리의 경우 시기별 품질 차이를 보였다. 단위 화분당 어 린순 생산성은 1,300mL에서 가장 높았으나, 단위 면적당으 로 환산할 경우 750mL에서 가장 우수하게 관찰되었다. 따라 서 로즈마리 어린순 다단재배를 통한 집약생산에 가장 적합한 용기 크기는 750mL로 판단된다.

By the recent fast growth of e-commerce markets, it has been stimulated to study order picking systems to improve their efficiency in distribution centers. Many companies and researchers have been developed various types of order picking systems and pursued the corresponding optimal operation policies. However, the performances of the systems with the optimal policies often depend on the structures of the centers and the operation environments. Based on a simulation model that mimics a unique zone picking system operated by a real company in the Republic of Korea, this study compares several operation policies and finds the most appropriate order selection rule and worker assignment policy for the system. Under all scenarios considered in this study, simulation results show that it is recommendable to assign more efficient workers to the zones with heavier workload. It also shows that selecting the order with the maximum number of non-repeatedly visited zones from the order list provides the most consistent and stable performances with respect to flow time, makespan, and utilization of the system even under the scenario with the breakdown zones. On the other hand, selecting the order with the minimum ratio of penalty to the number of zones performs the worst in all scenarios considered.

본 연구는 22대 총선에 있어 제3지대 정당인 녹색정의당과 개혁신당, 새로운미래, 조국혁신당의 공천과정을 살펴보는 것을 목적으로 한다. 제3 지대 정당인 새로운미래와 개혁신당은 총선 90일전에 창당되었고, 조국 혁신당은 총선을 한 달 정도 남겨놓고 창당해 비례대표국회의원만 추천 하였다. 특히 제3지대 정당은 거대 양당제도의 구축으로 인해 지역구 국 회의원의 당선 가능성이 낮아 비례대표 국회의원 의석확보에 초점을 맞 추고 있다. 그리고 제3지대 정당의 후보공천 규칙은 유사했으며, 조국혁 신당은 3월3일 창당을 하면서 구체적인 후보자격심사에 대한 규정을 내 놓지는 않았다. 이러한 공천룰에 따라 지역구 후보와 비례대표 후보의 국회입성에 따라 제3지대 정당의 역할론이 대두될 것이다.

PURPOSES : The effect of yellow carpet visibility enhancement was verified and its impact on traffic safety for effective introduction of traffic safety facilities was studied. METHODS : There is currently no scientific evidence demonstrating that yellow carpets improve pedestrian awareness. In this study, the effect of increasing visibility caused by the installation of yellow carpet was verified, and the effect of improving the level of traffic safety was examined through an objective analysis. A drone was used to collect and analyze video data to compare the driving speeds of vehicles passing near yellow carpets at six different sites and diagnose the effects of speed reduction. RESULTS : The results showed that the visibility improvement values before and after the installation of the yellow carpet differed from place to place, but a visibility improvement effect existed in certain cases. In terms of the adequacy of the installation site, the yellow carpet had no deceleration effect on vehicles driving on signalized local streets and collector highways. It was found that there was a speed reduction effect on unsignalized local streets. CONCLUSIONS : To enhance traffic safety promotion, yellow carpets should be placed on unsignalized local streets. It is important to place the yellow carpet in the right place in a proper manner.

The waste secondary battery contains a significant amount of valuable metals, making its recycling highly desirable. However, conventional chemical methods for recycling are environmentally unfriendly and cost-ineffective. Rather than the chemical method, this paper deals with a mechanical method for recovering electrode materials from waste secondary batteries by blowing pressurized air onto the interface area between the electrode and the separator. Especially, in this study, the effective blowing angle were searched by simulating the separation of the electrode material from the separator through 1-way fluid structure interaction analysis based on the Cohesive Zone Modeling technique.

This study was conducted to identify the optimal root zone temperature for paprika cultivation, with an aim to increase the heating and cooling energy efficiency and prepare for extreme weather conditions. The greenhouse air temperature was maintained at 20oC and 25oC during the daytime (12 hours) and at 18oC during the nighttime (12 hours). The plant height did not show any significant differences between the treatment with air temperature and root zone temperature. The root length was highest under an air temperature of 25oC with root zone temperatures of 25oC and 30oC, and it was the lowest at 15oC. The leaf number was the highest when the root zone temperature was adjusted to 25oC and 30oC across all air temperatures. The leaf area increased with higher root zone temperatures, but considering the compactness of the seedlings, a root zone temperature of 25oC was found to be the most effective. The fresh and dry weight of the shoot increased with higher root zone temperatures at an air temperature of 25oC, while the fresh and dry weight of the roots tended to be higher when the root zone temperature was adjusted to 25oC and 30oC across all air temperatures. The compactness was most effective when the root zone temperature was adjusted to 20oC and 25oCC across all air temperatures. Based on the above results, adjusting the root zone temperature to 25oC at an air temperature of 25oC was found to be effective for the early growth of Paprika. The results of this study suggest that not only can growth be promoted through the regulation of root zone temperature, but it also contribute to the establishment of root zone temperature control technology, which can prevent an excessive drop and rise in the root zone temperature.

본 연구는 무안만 조간대의 대형저서생물 군집구조와 퇴적물의 유기물 분포특성과의 관계를 알아보기 위해서 수행되었다. 2019년 8월에 21개 정점에서 퇴적층을 채취하여 입도 및 유기 물 함량(강열감량과 총유기탄소함량)을 분석하였다. 또한 대형저서동물을 분류하고 분포특성을 조사하였다. 조간대 퇴적층의 입도는 무안만 북측 내만이 비교적 조립하였고, 만 입구 주변 은 주로 실트질의 특성을 보였다. 유기물 함량(강열감량과 총유기탄소함량)은 목포 지역 근처 에 위치한 정점 10에서 가장 높았으며, 만의 북측에 위치한 정점 20이 가장 낮았다. 출현한 대형저서동물 중 10% 이상의 점유율을 보인 종은 기수우렁이류(Assiminea sp.), 종밋(Musculista senhousia), 비틀이고둥(Cerithideopsilla cingulata)이었고, 고리버들갯지렁이(Heteromastus filiformis) 4종이었다. 정점 10에서 전체 정점과 비교하여 최대 종수와 밀도를 보였다. 출현종을 토대로 집괴분석과 다차원척도법을 실시한 결과 무안만 조간대는 총 4그룹으로 구분되었다. 상관분석 결과 총유기탄소함량과 생물밀도는 유의한 상관관계(p<0.05)를 보였다. 본 연구결과 에 의해 무안만 조간대에 있어서 대형저서동물 분포는 입도 및 유기물 함량에 따라 다양하게 나타나는 것을 확인할 수 있었다.

The Derived Concentration Guideline Level (DCGL) is required to release the facility from the nuclear safety act at the stage of site restoration of the decommissioning nuclear power plant. In order to evaluate DCGL, there are various requirements, and among them, the selection of input parameters based on the application scenario is the main task. Especially, it is important to select input parameters that reflect site characteristics, and at this time, a single deterministic value or a probabilistic distribution can be applied. If it is inappropriate to apply a particular single value, it may be reasonable to apply various distributions, and the RESRAD code provides for evaluation using probabilistic methods. Therefore, this study aims to analyze the difference between the application of the deterministic method and the application of the probabilistic method to the area and thickness of the contaminated zone among the site characteristics data. This study analyzed the thickness and area of the contaminated zone, and in the case of thickness, the deterministic method was applied by changing the thickness at regular intervals from the minimum depth considered by MARSSIM to the thickness of the unsaturated zone identified in previous research data. In addition, a probabilistic analysis was performed by applying a distribution to the thickness of contaminated zone. Second, for the area of the contaminated zone, the dose was evaluated for each area in consideration of the areas to be considered when deriving Area Factor (AF), and the resulting change in DCGL was observed. As a result, the DCGL tends to decrease as the thickness increases, and it seems to be saturated when the thickness exceeds a certain thickness. Therefore, It was confirmed that the level of saturated values is similar to that of entering a probabilistic distribution, and in the case of a parameter that is reasonable to enter as a distribution rather than as a single value, it is sufficiently conservative to perform a probabilistic evaluation. In the case of area change, the DCGL evaluation result showed that the DCGL increased as the scale decreased. The magnitude of the change varies depending on the characteristics of each radionuclide, and in the case of radionuclides where external exposure gamma rays have a major exposure effect, the change is relatively small. It can be seen that the change in DCGL according to the area has the same tendency as the AF applicable to the survey unit for small survey units applied in the final status survey.

Deep disposal facility for High-Level radioactive Waste (HLW) uses a multi-barrier system to prevent the leakage of radionuclide. As a part of the engineered barrier, bentonite is primarily considered as the main buffering material. This is due to the adsorption and swelling properties of the bentonite, which are expected to effectively impede leakage of the radionuclide. In many cases, adsorption is generally regarded as occurring only within the buffer zone. However, several research has been conducted to explore the possibility of bentonite intrusion into the Excavation- Damaged Zone (EDZ) generated during excavation processes, because of the swelling properties of the bentonite. Generally, for host rock near the deep disposal facility such as granite, groundwater flows through the fracture network. Therefore, analysis of the characteristics of the fracture network is essential for predicting the behavior of radionuclide in groundwater. Accordingly, the bentonite intrusion into the fracture network is critical for safety assessment of the deep disposal facility. To analyze this, hydro-geochemical model was established utilizing COMSOL Multiphysics and PHREEQC, observing changes of the behavior of U (VI) along fracture network due to the swelling of bentonite. Modeling was conducted with progressively changing intrusion depth of the bentonite. According to the results, the behavior of U (VI) exhibited significant changes depending on the connectivity of the fractures. Based on the distribution characteristics of the fracture network, heterogeneous groundwater flow was observed. U (VI) was transported through the preferential pathway, which indicates high connectivity, due to the rapid groundwater flow. Notably, when changing the intrusion depth of bentonite, significant differences in behavior of U (VI) were observed in the 0-20 cm case. In contrast, as the intrusion depth increased, it was observed that differences became less evident. These results indicate that changes in the properties of fracture network in EDZ due to the swelling of bentonite significantly influence the behavior of U (VI).

Raman characteristics of various minerals constituting natural rocks collected from uranium deposits in Okcheon metamorphic zone in Korea are presented. Micro-Raman spectra were measured using a confocal Raman microscope (Renishaw in Via Basis). The focal length of the spectrometer was 250 mm, and a 1800 lines/mm grating was installed. The outlet of the spectrometer was equipped with a CCD (1,024256 pixel) operating at -70°C. Three objective lenses were installed, and each magnification was 10, 50, and 100 times. The diameter of the laser beam passing through the objective lens and incident on the sample surface was approximately 2 m. The laser beam power at 532 nm was 1.6 mW on the sample surface. Raman signal scattered backward from the sample surface was transmitted to the spectrometer through the same objective lens. To accurately determine the Raman peak position of the sample, a Raman peak at 520.5 cm-1 measured on a silicon wafer was used as a reference position. Since quartz, calcite, and muscovite minerals are widely distributed throughout the rock, it is easy to observe with an optical microscope, so there is no difficulty in measuring the Raman spectrum. However, it is difficult to identify the uraninite scattered in micrometer sizes only with a Raman microscope. In this case, the location of uraninite was first confirmed using SEM-EDS, and then the sample was transferred to the Raman microscope to measure the Raman spectrum. In particular, a qualitative analysis of the oxidation and lattice conditions of natural uraninite was attempted by comparing the Raman properties of a micrometer-sized natural uraninite and a laboratory-synthesized UO2 pellet. Significantly different T2g/2LO Raman intensity ratio was observed in the two samples, which indicates that there are defects in the lattice structure of natural uraninite. In addition, no uranyl mineral phases were observed due to the deterioration of natural uraninite. This result suggests that the uranium deposit is maintained in a reduced state. Rutile is also scattered in micrometer-sizes, similar to uraninite. The Raman spectrum of rutile is similar in shape to that of uraninite, making them confused. The Raman spectral differences between these two minerals were compared in detail.

Long-term climate and surface environment changes can influence the geological subsurface environment evolution. In this context, a fluid flow pathway developing and connection possibility can be increased between the near-surface zone and deep depth underground. Thus, it is necessary to identify and prepare for the overall fluid flow at the entire geological system to minimize uncertainty on the spent nuclear fuel (SNF) disposal safety. The fluid flow outside the subsurface environment is initially penetrated through the surface and then the unsaturated area. Thus, the previously proved reports, POSIVA in Finland, suggested that sequential research about the fluid infiltration experiment (INEX) and the investigation is necessary. Characterizing the unsaturated zone can help predict changes and ensure the safety of SNFs according to geological long-term evolution. For example, the INEX test was conducted at the upper part of ONKALO, about 50 to 100 m depth, to understand the geochemical evolution of the groundwater through the unsaturated zone, to evaluate the main flow of groundwater that can approach the SNF disposal reservoir, and to estimate the decreasing progress of the buffering capacity along the pathway through the deep geological disposal. In the present study, a preliminary test was performed in the UNsaturated-zone In-situ Test (UNIT) facility near the KAERI underground research tunnel to design and establish a methodology for infiltration experiments consistent with the regional characteristics. The results represented the methodological application is possible for characterizing unsaturated-zone to perform infiltration experiments. The scale of the experiment will be expanded sequentially, and continuous research will be conducted for the next application.

The microstructure and mechanical properties of the heat-affected zone welded using the GTAW process on SDSS material used in offshore structures were analyzed. The chemical composition of the specimen material was analyzed using XRF. The microstructure of the heat-affected zone where the plate was welded was examined by SEM, and the ferrite volume fraction was assessed using the point count method of ASTM E562. A lot of ferrite was formed in the overheated weldment region, and In the weld cap where the cooling rate was fast, ferrite was not converted back to austenite and the microstructure was not uniform. From the ferrite phase fraction, it was shown that it can be applied to the pitting resistance equivalent numbers through changes in mechanical properties according to welding conditions.

This study used optical and scanning electron microscopy to analyze the surface oxidation phenomenon that accompanies a γ'-precipitate free zone in a directional solidified CM247LC high temperature creep specimen. Surface oxidation occurs on nickel-based superalloy gas turbine blades due to high temperature during use. Among the superalloy components, Al and Cr are greatly affected by diffusion and movement, and Al is a major component of the surface oxidation products. This out-diffusion of Al was accompanied by γ' (Ni3Al) deficiency in the matrix, and formed a γ'-precipitate free zone at the boundary of the surface oxide layer. Among the components of CM247LC, Cr and Al related to surface oxidation consist of 8 % and 5.6 %, respectively. When Al, the main component of the γ' precipitation phase, diffused out to the surface, a high content of Cr was observed in these PFZs. This is because the PFZ is made of a high Cr γ phase. Surface oxidation of DS CM247LC was observed in high temperature creep specimens, and γ'-rafting occurred due to stress applied to the creep specimens. However, the stress states applied to the grip and gauge length of the creep specimen were different, and accordingly, different γ'-rafting patterns were observed. Such surface oxidation and PFZ and γ'-rafting are shown to affect CM247LC creep lifetime. Mapping the microstructure and composition of major components such as Al and Cr and their role in surface oxidation, revealed in this study, will be utilized in the development of alloys to improve creep life.