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Design and Construction of Green Infrastructure-Low Impact Development Experimental Complex for Hydrological cycle (부산대학교 GI·LID 물순환 실증단지 계획 및 구축)

  • Lee, Jae-Hyuk;Yoon, Eui-Hyeok;Jang, Young-Su;Shin, Hyun-Suk
    • Proceedings of the Korea Water Resources Association Conference
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    • 2016.05a
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    • pp.319-319
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    • 2016
  • 최근 급격한 기후변화와 도시화로 인하여 강우량 및 강우강도는 약 20% 증가하고 강우일수는 14% 감소하며 도시 기온이 최대 $3^{\circ}C$까지 증가하는 등의 현실적인 문제가 발생하고 있다. 이로 인한 도시 물순환체계의 파괴는 도시물관리 여건의 악화로 이어지고 특히 불투수면적 증가로 인한 도시 홍수 및 침수의 증가, 잦은 도시 고온 현상, 도시하천의 건천화로 수질 악화를 야기하는 실정이다. 이에 국토의 자연자원을 보전하고 기후변화에 적응하면서 도시의 안전도와 가치를 높이기 위한 물관리 정책은 먼저 물을 순환을 보다 적극적으로 반영하고 통합적인 물관리 체계 확보를 요구한다. 이를 위해서는 발생원 관리를 포함한 소규모 분산관리 체계로 변화하여야 하며 이들 시설에 대한 네트워크화를 통해 기후변화에 강건하고 통합관리쳬계를 구축하는 것이 중요하다. 이를 위해서는 저영향개발(LID, Low Impact Development) 및 그린인프라(GI, Green Infrastructure) 기반의 분산식 빗물관리기법의 도입이 절실하다. 현재 국내에서는 제도적으로 기후변화 대비, 지속가능한 도시환경 구축을 위한 물순환 건전화를 위해 100대 국정화제에 포함시키는 등(2013.2) 도시계획 및 기반시설 설치 LID기법의 법제적 산업적 도입을 추진중에 있으나, LID 기술의 수자원 치수, 이수 및 환경 효율성에 대한 객관적인 정보의 부재, LID 기술에 대한 효율성 검증 및 인증시스템의 부재, LID 기술의 무분별한 국외기술 도입으로 인한 효과 저감, LID 기술의 설계, 시공, 관리를 위한 매뉴얼 및 가이드라인의 부재, LID 기술에 대한 지자체 지원 및 전문가 양성 시스템의 부재 등 복합적인 문제를 안고 있어 GI 및 LID 기술의 적용을 통한 새로운 도시 및 유역차원의 수자원확보와 재해경감기술 패러다임 확보가 용이하지 않다. 이를 위해 본 연구에서는 강우유출수 관리를 위한 LID기술 신뢰도 향상 및 단일화, 표준화된 효율성 검증 기술 개발과 더 나아가서 도시-건축-수자원-도로-조경 등의 종합적인 인프라를 바탕으로 LID기술 통합관리 및 기술 고도화를 위해 부산대학교 GI LID 물순환 실증단지의 계획 및 구축을 수행하였다.

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Correlation Analysis between BMI and Bone Density in Menopause Women (폐경여성의 BMI와 골밀도의 상관관계 분석)

  • Kim, Hyeon-Jin
    • Journal of the Korean Society of Radiology
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    • v.15 no.7
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    • pp.1015-1020
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    • 2021
  • This study retrospectively analyzed the test results of 113 healthy postmenopausal women without special diseases among patients who visited a medical institution in Busan from January 2020 to June 2021. The purpose of the study was to investigate the effect of BMI (Body Mass Index) on bone density in menopause women, the analysis of the lumbar and femur of patients with low weight (BMI<18.5) showed a significant probability (p-value) of 0.000, and the normal weight (18.5≦BMI<23.0) of the femur. In overweight (23.0≦BMI<25.0), the significance probability (p-value) of the lumbar region was 0.021 and the significance probability (p-value) of the femur was 0.034, confirming the correlation. However, in patients with high obesity (30.0≦BMI<40.0), the p-value of the lumbar region was 0.127, and the p-value of the femur was 0.093, indicating that there was no correlation between BMI and bone density.

A Study on the Standardization Method of Wild Seedlings of Abies koreana E.H. Wilson on Mt. Hallasan (한라산 구상나무(Abies koreana E.H. Wilson)의 천연묘 기준화 방안 고찰)

  • Choi, Im Jun;Lee, Jong-Won;Kang, Shin-Ho
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.04a
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    • pp.73-73
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    • 2019
  • 전나무속(Abies Miller, 1754)은 지구상에서 북반구를 중심으로 50여 종이 현존하고 있다. 전나무속은 주로 높은 고도의 산지 또는 수목 한계선 주변에 자연적 분포지를 형성하고 있으며, 국내에는 전나무(A. holophylla), 분비나무(A. nephrolepis) 및 구상나무(A. koreana), 총 3종이 자생하고 있다. 하지만 국내에 자생하는 3종의 경우도 쇠퇴가 급격히 진행되고 있다. 특히 대한민국 특산식물인 한라산의 구상나무는 IUCN Redlist 상의 'Threatened species' category 종으로 등재되어 있을 뿐만 아니라 구상나무 어린 나무(치수)의 수가 급격히 줄어 우리 사회에서 문제가 직면한 '저출산 고령화 사회'와 유사하다고 할 수 있다. 하지만, 구상나무의 어린 나무에 관한 연구가 미비한 실정이다. 게다가 선행연구에서도 어린 나무의 기준이 모호하다. 따라서 본 연구는 구상나무 등 국내 자생하는 구상나무 천연묘의 기준을 정립하여 추후 진행되는 구상나무 등 전나무속 어린 나무에 관한 연구에 표준화를 유도할 수 있을 것으로 기대된다. 우선, 국내.외 소나무과 어린나무에 관한 논문을 정리 및 분석하였고, 구상나무 어린나무가 자생하는 숲의 구조(제주조릿대 등) 및 환경(암석노출도) 등)에 적절한 높이와 아린흔의 갯수를 참고로 기준안을 제시해 보고자 한다. 본 연구의 기준안은 선행연구에서 조사된 구상나무 어린나무 3,138개체의 높이 및 아린흔 갯수를 토대로 구분해볼 수 있었다. 우선, 높이에 대한 기준은 1년생묘(당해묘, 5cm 미만)-유묘(5cm~10cm 미만)-성묘(대묘, 10cm~30cm 미만)-치수(30cm~100cm 미만) cf.전생치수-유목(100cm 이상) 5단계로 구분되었다. 아린흔 갯수에 대한 기준도 또한 1년생묘(1개)-유묘(2개~6개)-성묘(대묘, 7개~15개)-치수(16개~20개) cf.전생치수-유목(21개 이상) 5단계로 구분되었다.

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Evaluation of the pre treatment tank filter media layer in LID technologies (LID 기법 전처리 시설 내 여재층 특성 평가)

  • Choi, Hye Seon;Jeon, Min Su;Geronimo, Franz Kevin;Reyes, Nash Jett;Kim, Lee Hyung
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.367-367
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    • 2022
  • 토지이용의 고도화에 따라 비점오염원 부하는 증가하는 추세이며 기후변화에 따른 강우강도 증가 등으로 지표면에 축적된 고농도의 비점오염물질이 하천으로 유출, 수질오염을 가중시키고 있어 비점오염원 관리가 필요하다. LID 기법은 자연적 기작(mechanisms)과 공정(process)을 이용하여 생태계의 물질순환(물순환 포함)과 에너지 흐름이 원활하도록 조성하는 기법으로, 불투수층면에서 발생되는 강우유출수를 관리 가능하다. LID 시설에는 전처리 시설을 두어 초기 고농도의 입자상 물질을 저감시키고, 강우유출수 저류공간을 통한 유출저감, 첨두유량 등을 저감시킨다. 이러한 전처리 시설에는 유기물질 및 영양소의 생물학적 제거를 위한 미생물 서식공간의 제공 등의 역할을 수행하기 위하여 다양한 여재를 적용하고 있다. 본 연구는 비점오염물질 유입이 LID 기법 전처리 시설 내 여재층의 물리·화학적 및 생물학적 환경을 평가하였다. 3개 시설 모두 100%의 불투수층에서 발생되는 강우유출수를 처리하는 LID 시설을 연구대상으로 선정하였으며, 각각의 전처리 시설에는 자갈, 우드칩, 쇄석 등이 적용되어 있다. 퇴적물의 경우 가장 상부에 존재하는 층으로 퇴적물의 오염물질 농도는 2~10.7배 이상 매우 높게 나타났다. 우드칩의 경우 다른 여재에 비해 높은 함수량과 유기물 함량을 보였으며 이는 우드칩의 수분을 보유하는 능력과 거친 표면공극에 오염물질이 부착되기 때문으로 나타났다. 또한, 같은 무기성 여재인 쇄석과 자갈의 경우 여재 크기의 차이를 보임에도 불구하고 미생물의 군집구성과 함수량의 차이를 보이는 것으로 평가되었다. 유기물의 함량이 낮은 강우유출수의 생물학적 처리능력을 향상시키기 위해서는 유기성 여재가 필요하며, 다공성 무기 멀칭재를 적용하고 하부의 토양은 적정 유기물을 배합하여 질산화 및 탈질화 유도가 가능하도록 설계가 필요한 것으로 분석되었다.

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Promoted rooting of softwood cuttings of highbush blueberry 'Duke', 'Elizabeth', 'Elliot' (Vaccinium corymbosum L.) as affected by indole-3-butyric acid(IBA) dipping treatment (Indole-3-butyric acid(IBA) 침지처리에 의한 highbush blueberry 'Duke', 'Elizabeth', 'Elliot' (Vaccinium corymbosum L.)의 녹지삽목 발근 촉진)

  • Kang, S.K.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.17 no.1
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    • pp.145-155
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    • 2015
  • To investigate the practicality of a small scale softwood propagation plastic film tent and the rooting promoting effect of indole-3-butyric acid(IBA) for northern highbush blueberry, softwood cuttings of 3 varieties (Duke, Elizabeth, Elliot) were made after dipping in the IBA solutions of 100ppm, 300ppm, 500ppm, 1,000ppm for 2 hour, and 3,000ppm for 20 seconds, respectively. Two-way ANOVA confirmed the significant differences in the percentage of rooting of cutting, longest root length and rooting volume index (RVI) induced by IBA treatment, as well as the percentage of rooting of cutting and RVI among examined varieties. In particular, the highly significant difference was observed in th RVI for IBA treatment. However, there was no interactions between the auxin treatments and varieties. Spontaneous rooting ability (control) depends on the varieties, showing that the lowest rooting ability was observed in the 'Duke' (45%) followed by 'Elliot'(85%) and 'Elizabeth' (90%). In addition, the rooting of the examined 3 varieties were enhanced by both of short time (20sec) dipping treatment of low level solutions, and long time (2hr) dipping treatment of high level solution, with the remarkably promoted rooting of the 'Duke' cuttings.

Minimum Separation Distance Calculation for Small Unmanned Aerial Vehicles using Flight Simulation (비행 시뮬레이션을 이용한 소형 무인항공기의 최소 분리 거리 산출)

  • Junyoung Han
    • Journal of Advanced Navigation Technology
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    • v.28 no.1
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    • pp.15-20
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    • 2024
  • The utilization of small unmanned aerial vehicles (UAVs) has expanded into both military and civilian domains, increasing the necessity for research to ensure operational safety and the efficient utilization of airspace. In this study, the calculation of minimum separation distances for the safe operation of small UAVs at low altitudes was conducted. The determination of minimum separation distances requires a comprehensive analysis of the total system errors associated with small UAVs, necessitating sensitivity analysis to identify key factors contributing to flight technology errors. Flight data for small UAVs were acquired by integrating the control system of an actual small UAV with a flight simulation program. Based on this data, operational scenarios for small UAVs were established, and the minimum separation distances for each scenario were calculated. This research contributes to proposing methods for utilizing calculated minimum separation distances as crucial parameters for ensuring the safe operation of small unmanned aerial vehicles in real-world scenarios.

Technology Trends in CubeSat-Based Space Laser Communication (큐브위성 기반 우주 레이저 통신 기술 동향)

  • Chanil Yeo;Young Soon Heo;Siwoong Park;Hyoung Jun Park
    • Journal of Space Technology and Applications
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    • v.4 no.2
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    • pp.87-104
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    • 2024
  • CubeSats are being utilized in various fields such as Earth observation, space exploration, and verification of space science and technology due to their low cost, short development period, enhanced mission-oriented performance, and ability to perform various missions through constellation and formation flights. Recently, as the availability of CubeSats has increased and their application areas have expanded, the demand for high-speed transmission of large amounts of data obtained by CubeSats has increased unprecedentedly. Laser-based free space optical communication technology is capable of transmitting large amounts of data at high speeds compared to the existing radio communication methods, and provides various advantages such as use of unlicensed spectrum, low cost, low power, high security characteristics, and of use a small communication platform. For this reason, it is suitable as a high-performance communication technology to support CubeSat missions. In this paper, we will present the core components and characteristics of CubeSat-based space laser communication system, and recent research trends, as well as representative technology development results.

Comparison of Korean and Japanese Female College Students' Obesity Recognition and Life Style (한·일 여대생들의 비만에 대한 인식 및 생활패턴 비교)

  • Kim, Mi-Ok;Sawano, Kayoko
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.5
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    • pp.699-708
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    • 2010
  • This study looked into the obesity status, recognition of obesity, attitude towards obesity, eating and exercise habits, and lifestyles of Korean (n=101) and Japanese (n=123) female college students. All students were 21-years-of age, with an average height of 161 cm and the average weight of 54 kg. Korean female students responded that obesity complicated friendships, and hindered study and exercise. Japanese students did not express these opinions. Both Korean and Japanese students tended to over-consume their favorite food. Korean students ate breakfast about 24.8% everyday, while 48% of Japanese students did; both regularly ate dinner. Snack preference was mainly biscuits. The factor most influencing eating habits were TV advertisement for Korean students (57.4%) and parents for Japanese students (47.2%). Once-weekly exercise was done regularly by 34.7% of Korean students but only 20.3% of Japanese students. The main reason for Korean students to exercise was weight reduction (53.5%), while 78.2% did not exercise because it was tiring. Korean and Japanese students had similar life styles, although stress relief in Korean students was sought through conversations with friends and by reading books or listening to music for Japanese students.

Imaging Findings of Pneumothorax Caused by Bronchial Cartilage Hypoplasia in a Dog (개에서 기관지 연골 저형성에 의해 발생한 기흉의 영상학적 진단 증례)

  • Kim, Su-yeon;Kim, Seong-soo;Lee, Jeo-soon;Yun, Soo-kyung;Oh, Hyun-jung;Shon, Jung-min;Kim, Bo-eun;Kim, Wan-hee;Yoon, Jung-hee;Choi, Min-cheol
    • Journal of Veterinary Clinics
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    • v.32 no.5
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    • pp.469-472
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    • 2015
  • A 10-year-old, castrated poodle dog presented with a cough for 2 weeks, and the cough initially developed since very young age. On radiographs, pneumothorax was noticed by characteristics of radiolucent area without pulmonary markings along the thoracic wall and diaphragm, retracted lung lobes from the thoracic wall and severely decreased volume of the left cranial lung lobe with disconnected bronchus. Computed tomography (CT) findings identified several pulmonary air-filled cysts and collapsed lung with abnormal shape and non-tapered end of bronchus, bronchioles at the accessory lobe and left cranial lobe. Also, pneumothorax, pneumomediastinum and subcutaneous emphysema were found. Imaging diagnosis was the spontaneous pneumothorax caused by ruptured emphysematous bullae associated with congenital bronchial cartilage abnormality or bronchial tree malformation. On surgery, hypoplasia of the left cranial lobe, right middle lobe, and accessory lobe with a bulla where air was leaking was identified. The accessory lobe was partially resected and bronchial cartilage hypoplasia was confirmed by histopathologic examination.

Evaluating of the Effectiveness of RTK Surveying Performance Based on Low-cost Multi-Channel GNSS Positioning Modules (다채널 저가 GNSS 측위 모듈기반 RTK 측량의 효용성 평가)

  • Kim, Chi-Hun;Oh, Seong-Jong;Lee, Yong-Chang
    • Journal of Cadastre & Land InformatiX
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    • v.52 no.2
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    • pp.53-65
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    • 2022
  • According to the advancement of the GNSS satellite positioning system, the module of hardware and operation software reflecting accuracy and economical efficiency is implemented in the user sector including the multi-channel GNSS receiver, the multi-frequency external antenna and the mobile app (App) base public positioning analysis software etc., and the multichannel GNSS RTK positioning of the active configuration method (DIY, Do it yourself) is possible according to the purpose of user. Especially, as the infrastructure of multi-GNSS satellite is expanded and the potential of expansion of utilization according to various modules is highlighted, interest in the utilization of multi-channel low-cost GNSS receiver module is gradually increasing. The purpose of this study is to review the multi-channel low-cost GNSS receivers that are appearing in the mass market in various forms and to analyze the utilization plan of the "address information facility investigation project" of the Ministry of Public Administration and Security by constructing the multi-channel low-cost GNSS positioning module based RTK survey system (hereinafter referred to as "multi-channel GNSS RTK module positioning system"). For this purpose, we constructed a low-cost "multi-channel GNSS RTK module positioning system" by combining related modules such as U-blox's F9P chipset, antenna, Ntrip transmission of GNSS observation data and RTK positioning analysis app through smartphone. Kinematic positioning was performed for circular trajectories, and static positioning was performed for address information facilities. The results of comparative analysis with the Static positioning performance of the geodetic receivers were obtained with 5 fixed points in the experimental site, and the good static surveying performance was obtained with the standard deviation of average ±1.2cm. In addition, the results of the test point for the outline of the circular structure in the orthogonal image composed of the drone image analysis and the Kinematic positioning trajectory of the low cost RTK GNSS receiver showed that the trajectory was very close to the standard deviation of average ±2.5cm. Especially, as a result of applying it to address information facilities, it was possible to verify the utility of spatial information construction at low cost compared to expensive commercial geodetic receivers, so it is expected that various utilization of "multi-channel GNSS RTK module positioning system"