In this study, static and dynamic analyses were conducted on three atypical building models to evaluate the displacement response reduction performance based on the outrigger system installation location in a atypical building that incorporated both tapered and twisted shapes. Three 60-story models were developed with a fixed 3-degree taper and twist angles of 1, 2, and 3 degrees per story. Outrigger systems were installed at 10-story intervals and additionally between the 20th and 40th floor at 1-story intervals. The results indicated that, although there were variations depending on the seismic loads, the displacement response reduction performance was generally most effective when the outriggers were installed in the upper stories (41st to 60th floors) of the analytical models.
본 연구는 골프 레슨자가 인식한 레슨프로의 코칭 행동이 레슨만족 및 지속의사의 영향 관계를 규명하기 위하여 먼저 전문가 사전인터뷰(골프 프로 7명, 골프 전문가 2명)을 통해 사용된 문항을 확인하 였으며, 요인 간 문항 수는 코칭행동 6문항, 레슨만족 4문항, 지속의사 4문항의 선정 절차를 이루었다. 이 에 2024년 6월 1일~12월 23일까지 충청권에 소재한 골프연습장(12개소)를 선정, 표본추출법 (Non-probablity Sampling Method)을 통하여 불성실 답변자 21명을 제외한 총 181명을 SPSS와 AMOS 21.0(ver)을 활용 분석한 결과는 다음과 같다. 첫째, 자율적 코칭행동과 통제적 코칭행동은 레슨 만족에 유 의한 영향을 미치는 것으로 나타났다. 둘째, 자율적 코칭행동과 통제적 코칭행동은 지속의사에 유의한 영 향을 미치는 것으로 나타났다. 셋째, 레슨 만족은 지속의사에 유의한 영향을 미치는 것으로 나타났다. 이를 종합 해보면, 부분적으로 자율적 코칭뿐만 아니라 통제적 코칭에 대한 긍정적인 반응 역시 인식되어야 할 부분이며, 이는 프로의 레슨을 통해 골프 실력 향상의 목적이 분명하기 때문이다. 또한 골프 프로의 인적서 비스에 대한 다양한 평가가 이루어지는 만큼 그 역할의 소명 의식이 강조되는 부분으로 설명할 수 있다.
미·중 기술패권 경쟁 가운데, 첨단 디지털 기술의 공급망과 데이터 수 집, 유출, 조작, 유포 등의 우려가 제기되면서 공급망안보와 데이터안보 가 교차하는 양상이 두드러지기 시작했다. 데이터안보나 공급망안보 각 각에 대한 기존 연구는 있었으나, 이 둘의 교차점에 초점을 맞춘 연구는 드물다. 이 연구에서 다루는 데이터안보 사안들은 정부뿐 아니라 개인이 나 민간 행위자들이 취급하는 데이터들이 국가안보적 사안으로 전환되는 모습을 보인다. 이러한 신흥위협이 공급망위협과 상호작용하며, 국가안보 적 우려로 비화한 사례로 화웨이의 5G, ZPMC 항만 대형 크레인, 미래 자동차의 핵심 기술 라이다, 중국산 DJI 드론 등이 있다. 본 연구는 이러 한 사례들에 대해 국가 차원에서 어떤 대응이 이루어졌는지 탐구하였다. 특히, 관련 이슈들을 안보화하고 대응책을 앞서 제시하고 있는 미국에 초점을 맞추었다. 또한 기존의 안보화 이론을 보완하여 정치경제적 측면 을 추가하였다. 행정명령, 전략서 발간, 연방 예산안 그리고 새로운 전문 기구들의 창설을 통해 신흥 위협에 대처하고 있으며, 그 과정에서 공급 망 재편, 표준, 규범, 규제의 설립을 통해 변화하는 국가의 안보 제공자 로서의 역할을 조명하였다.
본 연구는 스포츠 전공 대학생의 배경적인 부분을 탐색하고, 전공선택동기가 전공만족 및 진로 결정수준에 어떠한 영향을 미치는지를 규명하기 위해 2023년 9월 1일~2024년 6월 28일까지 210명을 분 석한 결과는 다음과 같다. 첫째, 스포츠 전공 대학생의 전공선택동기는 전공만족에 유의한 영향을 미치는 것으로 나타났다. 둘째, 스포츠전공 대학생의 전공선택동기는 진로결정수준에 유의한 영향을 미치는 것으 로 나타났으며 특히, 외재적 동기는 낮은 수준의 결과를 나타내는 바 주변의 지지에 대한 영향력 향상에 노력이 필요하다. 마지막으로 전공만족은 진로결정수준에 유의한 영향을 미치는 것으로 나타났다. 이를 종 합 해보면, 스포츠 전공자라면 누구나 가지고 있는 분명한 목적을 들어내고자 하는 행동 즉 직업적 삶을 좌우하는 운동 기술, 커뮤니케이션 등 모든 영역 전문성 개발을 위한 노력이 필요하다는 것이다.
This study analyzed IoT-based indoor air quality monitoring data in a cooking room at a high school in Seoul. As a result of measuring the type and concentration change of cooking fumes generated during roasting, frying, and stir-fry, each cooking method showed a different pattern. Some cooking fumes were observed high during the distribution process, not during cooking, and it is necessary to observe and control indoor air quality during the entire process of cooking, storage, and distribution as well as various elements of cooking fumes. Through these results, we propose the addition of an IoT-based real-time indoor air quality monitoring system and ventilation facilities linked to it.
The importance of indoor air quality has significantly increased after the COVID-19 pandemic. This study analyzed the energy consumption of a ventilation system based on various operating methods considering indoor and outdoor conditions. From March to May 2024, experiments were conducted on ventilation systems installed in a hospital in Incheon, comparing the experimental and control groups. The results showed that using the bypass mode in the experimental group reduced total energy consumption by 25.34% compared to the control group. Additionally, utilizing the air-cleaner mode further reduced energy use. This study demonstrates that optimal use of bypass and air-cleaner modes can enhance energy efficiency. Further research is needed to verify long-term applicability under diverse conditions.
With technological and social development, high-rise atypical buildings have emerged. In order to take into account the structural vulnerability due to their high-rise atypical shape, systems such as vibration control system and seismic isolation can be applied. In this study, dynamic behavior characteristics analysis was conducted based on the location of the seismic isolation system installation of the atypical facade shape Tapered and reverse shell structure models. With the installation of Lead Rubber Bearing(LRB), the maximum story drift ratio showed a decrease, but the maximum absolute acceleration showed a phenomenon in which the response was amplified in the middle and low story. LRB1(base isolation system) is the most effective for simultaneous control of the two dynamic responses, but the 46th floor of ‘Nor’ and’ RS’ and the 41st floor of ‘TA’ are considered the most effective installation location of the seismic isolation system in consideration of the burden of the seismic isolation system and the structure stability.
The dome structure is suitable as a roof for large spatial structures because it can maintain the shape without installing columns in the internal space. However, the structure characteristics of the lower and upper structures of the dome structure are different, and damage may occur when an earthquake occurs. Therefore, in this study, mid-story isolation system was applied to the ribbed dome and geodesic dome structures to analyze the seismic response of the lower and upper structures according to the dome shape. As a result of the analysis, the displacement of the ribbed dome increased, but the deformation of the ribbed dome and the response of the lower structure decreased, and the seismic response of the geodesic dome decreased overall. From this result, the effect of the isolator according to the shape of the dome structure was confirmed, and the mid-story isolation is considered effective in reducing the seismic response of the upper and lower structures.
The diagrid structural system has a braced frame that simultaneously resists lateral and vertical loads, and is being applied to many atypical high-rise buildings for aesthetic effects. In this study, a 60-story structure with twisted degrees of 0° to 180° was selected to determine seismic response control performance of twisted high-rise structures whether the diagrid system was applied and according to the reduction of braced frame material quantity. For this purpose, ‘Nor’ model without the diagrid system and the ‘DS’ model with the diagrid system, which was modeled by reducing braced frame member section to 700~400, were modeled. As a result, the 'DS' model showed an seismic response control effect in all Twisted models even when the quantity was reduced, and especially, the Twisted shape model was found to have an superior response control effect compared to the regular structure. In addition, the ‘600DS’ analysis model, which matched the ‘Nor’ model by 99.0% in quantity, showed an increase in seismic response control performance as the rotation angle increased.
본 연구에서는 골프커뮤니티 시설을 이용 중인 이용객을 대상으로 서비스스케이, 긍정적 감정 반응 및 이용 만족이 어떠한 영향 관계가 있는가를 규명하기 위해 2023년 11월 9일 ~ 2024년 6월 17일까 지 242명을 분석한 결과는 다음과 같다. 첫째, 골프 커뮤니티 시설의 서비스스케이프는 긍정적 감정반응에 영향을 미치는 것으로 나타났다. 둘째, 서비스스케이프의 공조환경, 공간배치가 이용 만족에 부분적으로 영 향을 미치며, 이는 제공되는 환경적 수준과 밀접한 관계를 맺으며, 특히 청결한 환경에서 이용하길 원하는 지금의 이용객 성격이 반영된 결과로 판단된다. 마지막으로 긍정적 감정반응은 이용 만족에 유의한 영향을 미치는 것으로 나타났다. 커뮤니티 시설을 이용하는 대부분에 이용객들은 일상, 즉 삶과 밀접한 장소를 선 호하며, 특히 생활권 내 시설 이용에 대한 만족도가 높게 평가되는 만큼 시설에 대한 보수 정비 그리고 운 동환경에 대한 적절한 대비책이 필요하다 판단된다.
High-rise buildings are equipped with TMD (Tuned Mass Damper), a vibration control device that ensure the stability and usability of the building. In this study, the seismic response control performance was evaluated by selecting the design variables of the TMD based on the installation location of the twisted irregular building. To this end, we selected analysis models of 60, 80, and 100 floors with a twist angle of 1 degree per floor, and performed time history analysis by applying historical seismic loads and resonant harmonic loads. The total mass ratio of TMDs was set to 1.0%, and the distributed installation locations of TMDs were selected through mode analysis. The analysis results showed that the top-floor displacement responses of all analysis models increased, but the maximum story drift ratio decreased. In order to secure the seismic response control performance by distributed installation of TMDs in twisted irregular buildings, it is judged that the mass ratio distribution of TMDs will act as a key variable.
중재 시술의 발전으로, 노출된 방사선으로 인한 의료 방사선 중재 시술자에 미치는 건강 위협이 증대됨에 따라 시술 중 방사선 노출을 최소화하기 위한 관심과 노력이 요구되고 있다. 이에 대한췌장담도학회에서는 투시 장비를 이용한 중재 시술 중 의료 방사선 중재 시술자에게 미치는 방사선 노출을 최소화하기 위한 권고안을 개발하였다. 본 권고안은 방사선 차폐, 방사선 투시기와 방사선량의 관리, 방사선 노출 선량 한도 및 감시, 임신과 출산 총 4가지 분야로 나누어 중재 시술자에게 방사선 노출의 위험을 이해하기 위한 지식을 전달하고 실질적으로 수행해야 하는 권고사항을 명확히 제시하여 불필요한 방사선 노출을 피하기 위한 실용적인 접근이 가능하도록 구성되었다. 본 권고안을 통해 의료 방사선 중재시술자의 방사선 노출을 최소화하여 안전하고 효과적인 중재 시술이 이루어질 수 있기를 기대한다.
Since atypical high-rise buildings are vulnerable to gravity loads and seismic loads, various structural systems must be applied to ensure the stability of the structure. In this study, the authors selected a 60-story twisted-shaped structure among atypical high-rise structures as an analytical model to investigate its structural behavior concerning the outrigger system. The structural analyses were performed varying the number of installed layers and the arrangement of the outrigger system, as well as the placement of the mega column, as design variables. The analysis revealed that the most effective position for the outrigger was 0.455H from the top layer, consistent with previous studies. Additionally, connecting outriggers and mega columns significantly reduced the displacement response of the model. From an economic standpoint, it is deemed efficient to connect and install outriggers and mega columns at the structure's ends.
The directed energy deposited (DED) alloys show higher hardness values than the welded alloys due to the finer microstructure following the high cooling rate. However, defects such as microcracks, pores, and the residual stress are remained within the DED alloy. These defects deteriorate the wear behavior so post-processing such as heat treatment and hot isostatic pressing (HIP) are applied to DED alloys to reduce the defects. HIP was chosen in this study because the high pressure and temperature uniformly reduced the defects. The HIP is processed at 1150°C under 100 MPa for 4 hours. After HIP, microcracks are disappeared and porosity is reduced by 86.9%. Carbides are spherodized due to the interdiffusion of Cr and C between the dendrite and interdendrite region. After HIP, the nanohardness (GPa) of carbides increased from 11.1 to 12, and the Co matrix decreased from 8.8 to 7.9. Vickers hardness (HV) decreased by 18.9 % after HIP. The dislocation density (10-2/m2) decreased from 7.34 to 0.34 and the residual stress (MPa) changed from tensile 79 to a compressive -246 by HIP. This study indicates that HIP is effective in reducing defects, and the HIP DED Stellite 6 exhibits a higher HV than welded Stellite 6.
본 연구에서는 강합성라멘교의 벽체 배면 철근 커플러 적용 여부에 따른 두 실험체를 제작하여 하 중가력 실험을 수행하였다. 그 결과 공법에 적용된 주요 기술에 대한 구조적 안전성 및 적정성을 확인 하였으며, 실험체는 설계 내하력 대비 충분한 안전성을 확보하고 있음이 확인되었다. 또한, 경간장 17.3m, 교폭 3.0m, 높이 3.25m의 실험체에 대한 정적성능실험 및 동특성 측정 실험을 수행하였으며, 그 결과 설계 내하력 대비 충분한 안전성을 확보하고 있는 것으로 나타났다.
In this study, we investigated the dynamic characteristics of three irregular building models to analyze the effectiveness of displacement response control with Tuned Mass Damper (TMD) installation in twisted irregular buildings. The three irregular models were developed with a fixed angle of twist per story at one degree, subjected to three historical seismic loads and resonant harmonic loads. By designing TMDs with linear and dashpot attributes, we varied the total mass ratio of the installed TMDs from 0.00625% to 1.0%, encompassing a total of 10 values. Two TMDs were installed at the center of the top story of the analysis model in both X and Y directions to evaluate displacement response control performance based on TMD installation. Our findings suggest that the top displacement response control performance was most effective when a 1.0% TMD was installed at the top layer of the analysis model.
Pepper cultivation requires a great amount of manual labor, especially for varieties needing support stakes to prevent them bending or breaking in heavy winds or rain. In Korea, it is recommended to secure support stakes and string lines carefully, so as to minimize the risk of damage caused by typhoons. The harvesting of peppers is a labor-intensive process with low rates of mechanization.The removal of stakes is particularly time-consuming during mechanical harvesting, and lodging is a major issue during cultivation and mechanical harvesting. Given increased mechanization during pepper harvesting, it is important to consider these issues when undertaking variety development and cultivation method improvements. Further research and development are required to improve cultivation practices and develop pepper varieties that are more resistant to lodging. Therefore, this study aimed to investigate the impact of different cultivation methods on pepper lodging, thus broadening our knowledge on the desirable architecture of pepper plants required for lodging tolerance.
The term ‘lodging’ in agriculture is usually used when the crops fall from their upright position before harvesting. Various factors may be responsible, including inherent weaknesses in the stem, resulting from low lignin content or small root systems.Weather, such as strong winds or rains, will also likely increase lodging. Insect or disease damage can also weaken the plants, and cultural practices, such as fertilization, irrigation, and cultivation techniques, may increase the risk. Most of the research studies on lodging have been undertaken on cereal crops, but this is also an issue with many vegetable crops, and especially those that require mechanized harvesting. In this review, the issue of lodging in solanaceous vegetable crops is discussed, with an emphasis on the key risk factors and potential areas for future research that can identify damage mitigation strategies.