최근 증가한 상어의 출현빈도 증가는 상어 혼획의 증가와 더불어 상어에 의한 생태계 변화의 정밀 해석의 필요성으로 이어지고 있다. 안정동위원소는 생태학적 현상을 해석하 고 이해하는 데 사용되며, 상어의 이동에 대한 원인과 생태계 내 상어의 위치 및 생태를 이해하는데 도움이 될 수 있다. 본 총론에서는 한국의 상어 연구에서 영양 단계와 먹이 구성을 추정하고 이동 및 서식지 이용 패턴을 추론하기 위한 안정동위원소 기법의 활용을 제안하고자 한다. 연구자들이 이 접근법의 강점과 한계를 이해하는 데 도움을 주기 위해, 탄소 및 질소 안정동위원소의 영양 단계 판별 특성, 그리고 영양 단계 및 먹이 구성 추정을 위한 방법론적 고려 사항에 대한 간략한 개요를 제공하고자 하며 연골어류 특유의 특성에 대한 동위원소 기법의 주의 사항 및 화합물 안정동위원소비를 이용한 최신 연구도 소개한다. 안정동위원소 기법은 위내용물, 유전자, 생지화학적 마커와 공동 활용을 통해 상어 생태학에 대한 기본적인 의문을 해결하는 데 강력한 도구로 활용될 수 있을 것이다.

The world population is rapidly increasing; over the past 40 years, it has risen by 3.3 billion, reaching 7.8 billion people. Globally, Solanaceae plants contribute more than 6.5 million tons of food to the world’s diet, with potatoes being the fourth most produced crop, cultivated in over 300 countries. However, caution is necessary when consuming plants from the Solanaceae family, as they contain toxic substances known as alkaloids. While alkaloids can offer beneficial effects, such as antioxidants, anti-inflammatory compounds, and anti-cancer properties, tolerance to these compounds varies among individuals, meaning even very small amounts can have fatal effects.Among the major crops in the Solanaceae family, potatoes contain solanine and chaconine; tomatoes contain tomatine; and eggplants contain solasonine and solamargine. The concentration of these substances varies depending on the part of the plant, its developmental stage, and its variety. Additionally, levels can increase significantly due to environmental stress. The environment profoundly impacts the synthesis of secondary metabolites related to survival and defense. Research has confirmed that environmental conditions-such as high-temperature cultivation, low-temperature storage, drought and rainfall, strong light, weak light (shade conditions), and excessive fertilizer application-can increase alkaloid synthesis. Therefore, this study reviews research on alkaloids in Solanaceae crops.

This study proposes a method to evaluate the publicity of real-time, demand-responsive, autonomous public-transportation systems. By analyzing real-time data collected based on publicity evaluation indicators suggested in previous research studies, this study seeks to establish a system that objectively assesses the publicity of public transportation. Thus, the introduction of autonomous public transportation systems is expected to contribute to solving problems in underserved transportation areas and enable more sophisticated public transportation operations. We reviewed evaluation indicators proposed in previous studies. Based on this review, publicity evaluation indicators were derived and specific criteria were selected to assess systematically the publicity of autonomous public transportation. An AHP analysis was conducted to assess the relative importance of each indicator by analyzing the importance of the selected indicators. Additionally, to score the indicators, minimum and maximum target values were established, and a method for assigning scores to each indicator was examined. The most important factor in the publicity evaluation of autonomous demand-responsive transport (DRT) was the “success rate of allocation to weak public transportation service areas,” with a significance level p of 0.204. This was analyzed as a key evaluation criterion because of the importance of service provision in areas with low-public-transportation accessibility. Subsequently, “Accessing distance to a virtual station” (p = 0.145) was evaluated as an important factor representing the convenience of the service. “Waiting time after allocation” (p = 0.134) also appeared as an important evaluation factor, as reducing waiting time considerably affected service quality. Conversely, “compliance rate of velocity” yielded the lowest significance (p = 0.017), as speed compliance was typically guaranteed owing to autonomous driving technology. This study proposed a specific evaluation method based on publicity indicators to provide a strategic direction for improving services and enhancing the publicity of autonomous DRT systems. These results can serve as a foundational resource for improving transportation services in underserved areas and for enhancing the overall quality of public transportation services. However, the study’s limitation was its inability to use real-time autonomous public transportation data, relying instead on I-MoD data from Incheon. This limitation constrained the ability to establish universal benchmarks because data from various municipalities were not included. Future research should collect and analyze data from diverse regions to establish more reliable evaluation indicators.

The 81mm mortar barrel is a precision component requiring exact internal diameter measurements, which poses challenges in both machining and inspection using conventional equipment. This study addresses issues related to measurement variability and reprocessing due to inconsistencies in bore measurements along different barrel positions. Using Gage R&R analysis, we identified the limitations of the existing measurement system, particularly its inability to provide consistent and detailed readings along the full barrel length. To resolve these challenges, a revised measuring system was developed and compared with the existing system, showing enhanced accuracy and reduced errors. The improved system was subsequently applied to the barrel machining process, resulting in quality improvements in the final product.

본 연구의 목적은 은유분석 방법을 활용하여 정치교육과 관련한 학교 교육과정의 교과 및 비교과 학습 과정에서 형성된 학생들의 경험적 인식과 욕구가 어떠하며, 학교에서의 정치교육이 그 목표와 가치를 충 분히 실현하고 있는가를 확인하는 것에 있다. 이를 통해 학교 정치교육의 방향을 재고하고, 학생들의 특성 과 눈높이에 맞는 정치교육 교수 설계와 프로그램 개발을 위한 기초자료를 마련하고자 한다. 분석 결과 학교 정치교육에 대한 인식은 ‘일상’, ‘장벽’, ‘겉핥기’, ‘제도’의 네 가지의 범주로 도출되었다. 각 범주는 각각 2개의 주제어를 포함하고 있는데, 먼저 ‘삶’과 ‘상식’은 정치교육을 당연한 ‘일상’으로 받아들인다는 것을 의미하며 긍정적 인식이 다수 포함되었다. 둘째, ‘장벽’이라는 인식은 관련 교과의 내용적 요소에 대 한 ‘어려움’과 ‘중립’의 문제로 인해 원활한 교육이 이루어지지 않았다는 부정적인 인식을 의미한다. 셋째, ‘겉핥기’ 범주는 ‘허울’과 ‘허상’이라는 부정적 의미의 주제를 담고 있는데, 이는 현재 삶에 영향을 줄 만큼 배운 내용이 기억에 남아있지 않아 실속이 없거나 교과서 속의 이상적인 정치와 실제 현실의 정치가 매우 다르다고 느끼는 것을 의미한다. 마지막으로 ‘제도’로 바라 본 관점은 정치교육을 입시와 학업성취의 수단 적 ‘도구’로 바라보는 관점과 정치교육이 실제적 지혜를 쌓는 접근이라기보다 역사적 사실에 대한 개념적 지식 전달에 그치는 암기 위주의 개론 학습이라고 ‘형식’적으로 받아들였다는 것을 의미한다. 이러한 결과 를 바탕으로 하여 교육적, 정책적 시사점을 제시하였다.

In modern society, buildings are becoming more complex, and the population is becoming more densely populated. Such large buildings require a variety of evacuation measures, as there is a high possibility of large-scale human casualties due to increased evacuation distance and evacuation time in the event of a fire. Strobe light and exit sign light are used as important evacuation equipment to provide early warning and evacuation directions. In this thesis, we conducted a fire simulation assuming that a fire occurrence point notification function and a strobe light function were added to equipment such as visual alarms and evacuation guidance, and compared and analyzed the difference in evacuation completion time with existing equipment. The scenarios for the simulation were divided into “general fire situations” and “fire location and evacuation exit guidance situation” and the differences in evacuation completion time in the event of a fire were compared and analyzed for each floor from the 1st floor to the 3rd floor. The maximum travel distance to complete evacuation in the case of a fire on the first floor decreased by 80.6 m and the evacuation completion time decreased by 329.4 seconds, and the maximum travel distance to complete evacuation in the case of a second-floor fire decreased by 28.5 m and the evacuation completion time by 438.8 seconds. During the fire on the third floor, the maximum distance decreased until evacuation was completed to 3.4 m, and the evacuation completion time was reduced by 355.6 seconds. It is expected that if the congestion level of evacuation routes is reduced by utilizing the congestion level of evacuation exits when fire alarm systems and evacuation equipment are activated, the evacuation completion time will be further shortened and evacuations will be carried out quickly and safely.

This study aims to explore the development and current state of suppressor technology through a review of existing research and case studies, and to propose future directions for further research. Firstly, we analyze domestic and international research topics related to suppressors to determine emerging trends and research needs. Secondly, we investigate the reasons behind the discrepancies in noise reduction data from different studies that utilize identical measurement standards, proposing potential solutions to this issue. Furthermore, we examine key factors influencing suppressor performance, such as the design and shape of suppressors, including the effectiveness of baffle systems, pass-through suppressor technology, and fluid-filled suppressors. Additionally, we delve into the advancements in suppressor materials, assessing their durability, weight reduction, and thermal management capabilities, which are critical to the effectiveness and longevity of suppressors in modern warfare. This research contributes to the understanding of suppressor technology, highlighting the importance of design optimization and material innovation in enhancing both performance and practicality. The findings can guide the development of next-generation suppressors that meet the increasingly complex demands of contemporary combat environments.

Paradental cysts characteristically develop adjacent to the cervical margin on the lateral aspect of a tooth root and result from inflammatory processes within the periodontal pocket. Standard management usually involves cyst enucleation while striving to retain the affected tooth. Recurrence rates are infrequent following complete removal of the lesion. However, intentional replantation becomes necessary in cases with anatomical constraints or accessibility issues. We present the case of a 13-year-old female patient exhibiting delayed eruption of the mandibular left second molar, attributed to a cystic lesion located on the lingual-coronal aspect of the tooth.

본 연구는 COVID-19 팬데믹 상황에서 보건소 간호사로 근무한 경험을 심층적으로 이해하고, 본질을 규명하고자 시도되었다. C도의 3개 군 보건소에서 COVID-19 팬데믹 기간 동안 1년 이상 근무한 경험이 있는 대상자를 연구참여자로 선정하여 Colaizzi가 제안한 현상학적 방법에 따라 분석하였다. 연구결 과 ‘COVID-19에 대한 부정적 감정’, ‘직업적 소명의식 고취’, ‘신종 감염병 대응 체계 구축에 앞장’의 3가 지 주제모음이 도출되었다. 이를 바탕으로 간호사들을 위한 심리적 문제 지원 강화, 편중된 업무의 개선, 전문 인력 지원, 체계적 교육 지원, 적정 수준의 보상체계 마련 등의 필요성을 확인하였다. 따라서 본 연구 결과를 토대로 보건의료 체계 내 주요 인력인 간호사의 지지체계를 마련하고, 효율적인 감염병 대응 전략 을 마련하기 위해 다각도의 관심을 가지고 활발한 논의가 이루어져야 할 것이다.

PURPOSES : This study is to develop an comprehensive validation methodology for autonomous mobility-on-demand system with level 4 automated driving system. METHODS : The proposed method includes the quantitative techniques for validating both automated driving system and center system using each optimal indicators. In addition, a novel method for validating the whole system applying multi-criteria decision methodology is suggested. RESULTS : The relative weights for the vehicle system was higher than the center systems. Moreover, the relative weights of failure rate for validating the vehicle system was the highest, in addition to, a relative weight for accuracy of dynamic routing algorithm within center system was the highest. CONCLUSIONS : The proposed methodology will be applicable to validate the autonomous mobility on demand system quantitatively considering the relative weights for each systems.

본 연구는 초기 성인의 조건부 자아존중감이 열등감에 미치는 영향에서 SNS 상향비교와 SNS 이용동기가 어떠한 역할을 하는지 탐색하고자 하였다. 선행연구를 토대로 각 변인들의 관계에 대한 연구모형을 설정하여, 조절된 매개 효과를 검증하고자 하였다. 이를 위하여 온라인 설문지를 구성한 후, SNS를 이용하는 초기 성인 400명을 대상으로 설문조사를 실시하였으며, 최종적으로 총 351부를 분석에 활용하였다. 본 연구의 주요 결과는 다음과 같다. 첫째, 조건부 자아존중감, SNS 상향비교, SNS 이용동기, 그리고 열등감은 모두 정적 상관을 나타내었다. 둘째, 조건부 자 아존중감이 열등감에 영향을 미쳤으며 SNS 상향비교는 완전 매개하였다. 셋째, SNS 상향비교와 열등감의 관계에서 SNS 이용동기의 조절을 확인하였다. 마지막으로, 조건부자아존중감이 SNS 상향비교를 매개로 열등감에 미치는 간 접효과를 SNS 이용동기의 영향으로 조절하는 것을 확인하였다. 본 연구 결과를 바탕으로 초기 성인이 열등감을 경 험하는 것과 관련하여 심리적이고 정서적인 함의를 제시하였다.

PURPOSES : Recently, increasing number of local governments are introducing on-demand public transportation service in real time to improve the management efficiency of public transportation. In preparation for the autonomous driving era, the “autonomous public transportation mobility on-demand service in real time” is being developed in the public transportation sector to introduce on-demand public transportation. For this service to become the public transportation of the future, it must receive publicity. Therefore, in this study, indicators were selected to evaluate the publicity of the autonomous public transportation mobility on-demand service in real time, and a survey was conducted among the general public to examine the validity of the indicators. METHODS : To secure the publicity of on-demand public transportation in real time, the goal of the service was first set. Second, the keywords of the service were analyzed to define the publicity requirements of this service. Based on the analyzed keywords and definition of publicity, service indicator types were classified, and the indicators were defined by type. A user satisfaction survey was conducted on the final selected indicators to improve the degree of completion of indicator development. The user survey was conducted by presenting selected publicity indicators to respondents responding on a five-point scale to determine whether each indicator could satisfactorily evaluate publicity. RESULTS : When examining various previous research cases and the contents required for autonomous public transportation mobility on-demand service in real time, the required items of publicity indicators were found to be “safety” in terms of “autonomous driving” and “convenience” in terms of “demand response.” Publicity indicators were developed according to these three items. Thirty-one indicators were developed, and a satisfaction survey was conducted on the general public for each indicator. In the survey, most of the indicators scored 3.5 points or higher, indicating that the indicators were generally well defined. Users gave the highest score to “fairness” among the three items, and “reasonable fairness” was found to be a necessary item as a publicity indicator. CONCLUSIONS : In this study, evaluation indicators were selected to secure the publicity of autonomous public transportation mobility on-demand service in real time, and a satisfaction survey was conducted for each indicator. Most of the indicators showed a score of 3.5 or higher, indicating that they were generally well defined. However, this study has a limitation in that it surveys the general population. In future, experts should be included in the survey to increase the degree of completeness of the public indicators.

In assessing the seismic safety of nuclear power plants, it is essential to analyze the structures using the observed ground motion. In particular, spatial variation in which the characteristics of the ground motion record differ may occur if the location is different within the site and even if the same earthquake is experienced. This study analyzed the spatial variation characteristics of the ground motion observed at the structure and site using the earthquake records measured at the Hamaoka nuclear power plant. Even if they were located on the same floor within the same unit, there was a difference in response depending on the location. In addition, amplification was observed in Unit 5 compared to other units, which was due to the rock layer having a slower shear wave velocity than the surrounding bedrock. Significant differences were also found in the records of the structure’s foundation and the free-field surface. Based on these results, the necessity of considering spatial variation in the observed records was suggested.

본 연구는 찰스 쉴러(Charles Sheeler 1883-1965)의 주택실내회화(1926-34)에 나타난 미국적 모더니즘에 대한 연구이다. 쉴러는 1910년대부터 지속적인 관심을 두고 있었던 미국의 오래된 건물을 소재로 한 주택실내회화 5점을 제작했다. 본 연구는 당시 쉴러가 현대화·산업화를 주제로 한 작품을 통해 새로운 미국 미술의 선구자로서 인정받았음에도 불구하고, 오래된 주택의 실내를 화폭에 담고자 한 까닭은 무엇인지에 대한 의문으로부터 시작되었다. 이에 따라 쉴러의 주택실내회화가 지니고 있는 표현적 특성과 독자적인 의미를 밝히고, 보다 다양한 측면에서 그의 예술관을 고찰해보고자 한다. 쉴러는 주택실내회화를 통해 일루전과 추상의 결합을 시도하였다. 그는 입체주의의 특성을 자신만의 고유한 회화적 정체성으로 승화하기 위해 끊임없이 탐구했다. 또한 쉴러는 사진 활동을 하며 습득한 다양한 기법과 구성 방식, 사실 묘사의 기능을 강 화하면서도 카메라 시각으로 보는 추상적 구도와 형태를 회화로 재구성하였다. 그는 주택실내회화를 그릴 때 회화의 비매개적이고 환영주의적인 측면과 추상성을 결합하기 위해서 사진 작업을 활용한 것이다. 사진은 재현을 강화하기 위한 수단으로 사용했지만, 사진기의 각도와 렌즈의 조작에 의해 대상을 추상화할 수 있는 사진의 방법을 회화에 응용함으로써 새로운 효과를 창출해냈다. 쉴러의 주택실내회화에 나타난 일루전과 추상의 결합은 갑작스러운 것이 아니라, 그가 지속해서 연구한 결과물이자 점차적으로 미국 모더니즘으로 고취시킨 것이다. 쉴러는 기계문명을 찬미하는 이미지와 다른 자신의 주택실내 이미지를 통해 또 다른 미국의 대표적인 이미지로 승화시켰고 이것은 모더니즘 양식에 기초하여 추상적 가치를 시각적으로 구현했다는 점에서 독자적 가치를 지니고 있음을 확인할 수 있었다.

The spatial variation characteristics of seismic motions at the nuclear power plant's site and structures were analyzed using earthquake records obtained at the Fukushima nuclear power plant during the Great East Japan Earthquake. The ground responses amplified as they approached the soil surface from the lower rock surface, and the amplification occurred intensively at about 50 m near the ground. Due to the soil layer's nonlinear characteristics caused by the strong seismic motion, the ground's natural frequency derived from the response spectrum ratio appeared to be smaller than that calculated from the shear wave velocity profile. The spatial variation of the peak ground acceleration at the ground surface of the power plant site showed a significant difference of about 0.6 g at the maximum. As a result of comparing the response spectrums at the basement of the structure with the design response spectrum, there was a large variability by each power plant unit. The difference was more significant in the Fukushima Daiichi site record, which showed larger peak ground acceleration at the surface. The earthquake motions input to the basement of the structure amplified according to the structure's height. The natural frequency obtained from the recorded results was lower than that indicated in the previous research. Also, the floor response spectrum change according to the location at the same height was investigated. The vertical response on the foundation surface showed a significant difference in spectral acceleration depending on the location. The amplified response in the structure showed a different variability depending on the type of structure and the target frequency.

After the manual shutdown of the Wolseong nuclear power plant due to an earthquake in Gyeongju in 2016, anxiety about the earthquake safety of nuclear power plants has become a major social issue. The shear wall structure used as a major structural element in nuclear power plants is widely used as a major structural member because of its high resistance to horizontal loads such as earthquakes. However, due to the complexity of the structure, it is challenging to predict the dynamic characteristics of the structure. In this study, a three-story shear wall structure is fabricated, and the in-structure response characteristics of the shear wall structure are evaluated through shaking table tests. The test is performed using the Gyeongju earthquake that occurred in 2016, and the response characteristics due to the domestic earthquake are evaluated.

원자력시설 SPRA 방법으로서 기기 사이 부분 종속 관계를 정확하게 고려하기 위하여 샘플링기반접근법이 개발된 바 있다. 그러나 이는 샘플링 기반 방법이므로 정확한 지진 리스크 산정을 위하여 많은 수의 샘플을 추출해야 하는 단점이 있다. 이에 따라 본 연구에서 는 기존 방법을 개선하기 위한 효과적인 방법을 제안한다. 본 연구에서 제안한 방법의 주요한 특징은 다음과 같다. 기존 샘플링방법인 몬테카를로샘플링(MCS) 방법을 대신하여 다차원에서 효과적인 샘플링이 가능한 라틴하이퍼큐브샘플링(LHS) 방법을 샘플링기반 SPRA에 도입한다. 또한, 기존 지진세기 세분화 정도를 최종 지진 리스크 결과와 연계하여 결정한다. 제안된 방법이 결합된 샘플링기반 SPRA 접근법을 실제 원전 예제에 적용한 결과, 제안된 방법이 기존의 방법과 비교하여 결과 정확도에 있어서 거의 비슷하나 총 샘플 추출수 기준에서 효율성을 약 2배 가량 높이 것을 확인하였다. 또한, 샘플링 개수가 적은 영역에서 LHS 기반 방법이 MCS 기반 방법보다는 해의 정확도를 높이는 것을 확인할 수 있었다.

A powder mixture of 70 wt% Al2O3 and 30 wt% hydroxyapatite (HA) is sintered at 1300 ℃ or 1350 ℃ for 2 h at normal pressure. An MgF2-added composition to make HA into fluorapatite (FA) is also prepared for comparison. The samples without MgF2 show α & β-tricalcium phosphates (TCPs) and Al2O3 phases with no HA at either of the sintering temperatures. In the case of 1,350 ℃, a CaAl4O7 phase is also found. Densification values are 69 and 78 %, and strengths are 156 and 104MPa for 1,300 and 1,350 ℃, respectively. Because the decomposition of HA produces a H2O vapor, fewer large pores of 5-6 μm form at 1,300 ℃. The MgF2-added samples show FA and Al2O3 phases with no TCP. Densification values are 79 and 87%, and strengths are 104 and 143 MPa for 1,300 and 1,350 ℃, respectively. No large pores are observed, and the grain size of FA (1-2 μm) is bigger than that of TCP (0.7 μm ≥) in the samples without MgF2. The resulting TCP/Al2O3 and FA/Al2O3 composites fabricated in situ exhibit strengths 6-10 times higher than monolithic TCP and HA.