• Title/Summary/Keyword: Secondary System

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A Study on the Marker Tracking for Virtual Construction Simulation based Mixed-Reality (융합현실 기반의 가상건설 시뮬레이션을 위한 마커 추적 방식에 관한 연구)

  • Baek, Ji-Woong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.12
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    • pp.660-668
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    • 2018
  • The main object of this study was to find a way to operate the marker for simulating a virtual construction using a MR(mixed reality) device. The secondary object was to find a way to extract the form-data from BIM data, and to represent the virtual object by the MR device. A tiny error of scale causes large errors of length because the architectural objects are very large. The scale was affected by the way that the camera of the MR device recognizes the marker. The method of installing and operating the marker causes length errors in the virtual object in the MR system. The experimental results showed that the error factor of the Virtual object's length was 0.47%. In addition, the distance between the markers can be decided through the results of an experiment for the multi-marker tracking system. The minimum distance between markers should be more than 5 m, and the error of length was approximately 23mm. If the represented virtual object must be less than 20mm in error, the particular mark should be installed within a 5 m radius of it. Based on this research, it is expected that utilization of the MR device will increase for the application of virtual construction simulations to construction sites.

Growth of Tin Dioxide Nanostructures on Chemically Synthesized Graphene Nanosheets (화학적으로 합성된 그래핀 나노시트 위에서의 이산화주석 나노구조물의 성장)

  • Kim, Jong-IL;Kim, Ki-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.5
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    • pp.81-86
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    • 2019
  • Metal oxide/graphene composites have been known as promising functional materials for advanced applications such as high sensitivity gas sensor, and high capacitive secondary battery. In this study, tin dioxide ($SnO_2$) nanostructures were grown on chemically synthesized graphene nanosheets using a two-zone horizontal furnace system. The large area graphene nanosheets were synthesized on Cu foil by thermal chemical vapor deposition system with the methane and hydrogen gas. Chemically synthesized graphene nanosheets were transferred on cleaned $SiO_2$(300 nm)/Si substrate using the PMMA. The $SnO_2$ nanostuctures were grown on graphene nanosheets at $424^{\circ}C$ under 3.1 Torr for 3 hours. Raman spectroscopy was used to estimate the quality of as-synthesized graphene nanosheets and to confirm the phase of as-grown $SnO_2$ nanostructures. The surface morphology of as-grown $SnO_2$ nanostructures on graphene nanosheets was characterized by field-emission scanning electron microscopy (FE-SEM). As the results, the synthesized graphene nanosheets are bi-layers graphene nanosheets, and as-grown tin oxide nanostructures exhibit tin dioxide phase. The morphology of $SnO_2$ nanostructures on graphene nanosheets exhibits complex nanostructures, whereas the surface morphology of $SnO_2$ nanostructures on $SiO_2$(300 nm)/Si substrate exhibits simply nano-dots. The complex nanostructures of $SnO_2$ on graphene nanosheets are attributed to functional groups on graphene surface.

Safety and antifatigue effect of Korean Red Ginseng: a randomized, double-blind, and placebo-controlled clinical trial

  • Zhang, Li;Chen, Xiaoyun;Cheng, Yanqi;Chen, Qilong;Tan, Hongsheng;Son, Dongwook;Chang, Dongpill;Bian, Zhaoxiang;Fang, Hong;Xu, Hongxi
    • Journal of Ginseng Research
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    • v.43 no.4
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    • pp.676-683
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    • 2019
  • Background: Korean Red Ginseng (KRG) is widely used for strengthening the immune system and fighting fatigue, especially in people with deficiency syndrome. However, there is concern that the long-term application or a high dose of KRG can cause "fireness" (上火 in Chinese) because of its "dryness" (燥性 in Chinese). The aim of this study was to assess the safety and efficacy of a 4-week treatment with KRG in participants with deficiency syndrome. Methods: This was a 4-week, randomized, double-blind, placebo-controlled clinical trial. A total of 180 Chinese participants were randomly allocated to three groups: placebo control group, participants were given a placebo, 3.6 g/d; KRG 1.8 g and 3.6 g groups. The primary outcomes were the changes in fireness and safety evaluation (adverse events, laboratory tests, and electrocardiogram). The secondary outcomes were the efficacy of KRG on fatigue, which include the following: traditional Chinese medicine (TCM) symptom scale and fatigue self-assessment scale. Results: Of the 180 patients, 174 completed the full study. After 4 weeks of KRG treatment, the Fire-heat symptoms score including Excess fire-heat score and Deficient fire-heat score showed no significant change as compared with placebo treatment, and no clinically significant changes in any safety parameter were observed. Based on the TCM syndrome score and fatigue self-assessment score, TCM symptoms and fatigue were greatly improved after treatment with KRG, which showed a dose- and time-dependent effect. The total effective rate was also significantly increased in the KRG groups. Conclusion: Our study revealed that KRG has a potent antifatigue effect without significant adverse effects in people with deficiency syndrome. Although a larger sample size and longer treatment may be required for a more definite conclusion, this clinical trial is the first to disprove the common conception of "fireness" related to KRG.

The Effects of Oral Administration of Deer Antler Extracts on an Osteoporosis-induced Animal Model: A Systematic Review and Meta-analysis (골다공증 유발 동물모델에서 녹용 추출물의 경구 투여 효과: 체계적 문헌고찰 및 메타분석)

  • Lee, Jung Min;Kim, Nam Hoon;Lee, Eun-Jung
    • Journal of Korean Medicine Rehabilitation
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    • v.32 no.2
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    • pp.65-81
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    • 2022
  • Objectives This study aimed to assess the effects of oral administration of deer antler extracts on an osteoporosis-induced animal model. We analyzed the results of using deer antler single extracts on animal models with osteoporosis through a systematic review and meta-analysis. Methods We included osteoporosis studies in animal experiments that administrated deer antler extracts orally. We searched the following 13 databases without a language restriction: PubMed, EMBASE, Cochrane Library, Cumulative Index to Nursing and Allied Health Literature (CINAHL), China National Knowledge Infrastructure (CNKI), Wanfang, Korean Medical Database (KMbase), National Digital Science Library (NDSL), Korean Traditional Knowledge (Koreantk), Oriental Medicine Advanced Searching Integrated System (OASIS), Research Information Sharing Service (RISS), Korea Institute of Science and Technology Information (KISTI), and Koreanstudies Information Service System (KISS). We used Systematic Review Centre for Laboratory Animal Experimentation's risk of bias tool for assessing the methodological quality of the included studies. Results A total of 299 potentially relevant studies were searched and 11 were included for a systematic review. Nine studies used a single deer antler extract. A study compared the effects of single extracts of deer antler and antler glue, while another study compared the effects of three single extracts of deer antler, old antler, and antler glue. For evaluating the intervention effect, bone mineral density (BMD) was measured as the primary outcome, while the histomorphometric indicators of the bone and serum alkaline phosphatase and osteocalcin levels were used as the secondary outcome variables. On conducting a meta-analysis of studies on single deer antler extract, BMD was observed to be significantly increased compared to that in control group (standardized mean difference [SMD]=2.11; 95% confidence interval [CI]=1.58~2.65; Z=7.75; p<0.00001; I2=56%). As a result of meta-analysis, according to the concentration of deer antler, the group with high concentration showed statistically significantly higher BMD than the group with low concentration (SMD=1.28; 95% CI=0.74~1.82; Z=4.63; p<0.00001; I2=9%). Conclusions The research shows that the deer antler extracts have significant anti-osteoporotic effects on the osteoporosis-induced animal model. However the studies included in this research had a high methodological risk of bias. This indicates the requirement of considerable attention in the interpretation of the study results.

Waterbody Detection Using UNet-based Sentinel-1 SAR Image: For the Seom-jin River Basin (UNet기반 Sentinel-1 SAR영상을 이용한 수체탐지: 섬진강유역 대상으로)

  • Lee, Doi;Park, Soryeon;Seo, Dongju;Kim, Jinsoo
    • Korean Journal of Remote Sensing
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    • v.38 no.5_3
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    • pp.901-912
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    • 2022
  • The frequency of disasters is increasing due to global climate change, and unusual heavy rains and rainy seasons are occurring in Korea. Periodic monitoring and rapid detection are important because these weather conditions can lead to drought and flooding, causing secondary damage. Although research using optical images is continuously being conducted to determine the waterbody, there is a limitation in that it is difficult to detect due to the influence of clouds in order to detect floods that accompany heavy rain. Therefore, there is a need for research using synthetic aperture radar (SAR) that can be observed regardless of day or night in all weather. In this study, using Sentinel-1 SAR images that can be collected in near-real time as open data, the UNet model among deep learning algorithms that have recently been used in various fields was applied. In previous studies, waterbody detection studies using SAR images and deep learning algorithms are being conducted, but only a small number of studies have been conducted in Korea. In this study, to determine the applicability of deep learning of SAR images, UNet and the existing algorithm thresholding method were compared, and five indices and Sentinel-2 normalized difference water index (NDWI) were evaluated. As a result of evaluating the accuracy with intersect of union (IoU), it was confirmed that UNet has high accuracy with 0.894 for UNet and 0.699 for threshold method. Through this study, the applicability of deep learning-based SAR images was confirmed, and if high-resolution SAR images and deep learning algorithms are applied, it is expected that periodic and accurate waterbody change detection will be possible in Korea.

The Impact of the Subscription Economy on the Creation, Consumption and Distribution of the Art Market: Focused on Artnomics Gallery K (구독경제가 미술시장의 창작, 소비, 분배에 미치는 영향 - 아트노믹스 갤러리 K를 중심으로 -)

  • Han, Hyemi;Lee, Jin Woo
    • Korean Association of Arts Management
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    • no.57
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    • pp.33-58
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    • 2021
  • The purpose of this study is to understand the impact of the subscription economy on the contemporary art market in terms of creation, consumption and distribution of artwork. To accomplish the aim of this study, we conducted a case study of Artnomic Gallery K borrowing the theoretical perspective from Alexander(2003)'s Modified Cultural Diamond model. In this paper, we collected data through reviewing the secondary document and conducting in-depth interviews with 10 experts and consumers in the art market. As a result, the subscription economy eases the traditional art trade, which is heavily focused on a small number of market arts, by encouraging artists to create various works. The transition to subscription in the purchase of art contributes to lowering the barriers to entry into the art market by reducing the financial burden on consumers in terms of consumption. In terms of distribution, this founding of this article shows that the experts of Gallery K are the main actors in selecting the works that consumers subscribe to. Therefore, in this study, it is of academic significance to discuss that the filtering effect of the distribution system emphasized by Alexander(2003) is effective even in the art trading system to which a new form of economic activity - the subscription economy - is applied.

Design and Implementation of a Systemic Learner-centered Teaching Method Model - Focusing on H University - (체계적인 학습자 중심의 교수법 모델 개발 및 구현 - H 대학을 중심으로 -)

  • Kim, Sun-Hee;Cho, Young-Sik;Kim, Bo-Young;Han, Yong-Su
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.5
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    • pp.163-173
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    • 2021
  • This study tried to develop and implement a class model that can apply the teaching method that can operate learner-centered classes in university education to the class operation of the entire university, not individuals. For the development of the instructional model, the final model was derived through analysis of prior research, expert review, derivation of instructional model and design principles, pilot operation, primary questionnaire analysis, model and design strategy revision, and secondary questionnaire analysis. Shift_N+1 class consists of 6 models, and each model was divided into 3 parts. It was a preliminary learning using video, a face-to-face class for question-and-answer and in-depth learning on the core content, and feedback and process evaluation for individual student. We have built our own computer system so that we can implement this every week. The teaching method model that can apply the learner-centered curriculum to all classes at the university was standardized. The Shift_N+1 teaching method seeks to maximize the learner-centered learning effect by reflecting the characteristics of the subject, and to improve the quality of education by identifying students' achievements by week.

p-Type Activation of AlGaN-based UV-C Light-Emitting Diodes by Hydrogen Removal using Electrochemical Potentiostatic Activation (전기화학적 정전위 활성화를 사용한 수소 제거에 의한 AlGaN기반의 UV-C 발광 다이오드의 p-형 활성화)

  • Lee, Koh Eun;Choi, Rak Jun;Kumar, Chandra Mohan Manoj;Kang, Hyunwoong;Cho, Jaehee;Lee, June Key
    • Journal of the Microelectronics and Packaging Society
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    • v.28 no.4
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    • pp.85-89
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    • 2021
  • AlGaN-based UV-C light-emitting diodes (LEDs) were applied for p-type activation by electrochemical potentiostatic activation (EPA). The p-type activation efficiency was increased by removing hydrogen atoms through EPA treatment using a neutral Mg-H complex that causes high resistance and low conductivity. A neutral Mg-H complex is decomposed into Mg- and H+ depending on the key parameters of solution, voltage, and time. The improved hole carrier concentration was confirmed by secondary ion mass spectroscopy (SIMS) analysis. This mechanism eventually improved the internal quantum efficiency (IQE), the light extraction efficiency, the leakage current value in the reverse current region, and junction temperature, resulting in better UV-C LED lifetime. For systematic analysis, SIMS, Etamax IQE system, integrating sphere, and current-voltage measurement system were used, and the results were compared with the existing N2-annealing method.

Whose Science is More Scientific? The Role of Science in WTO Trade Disputes

  • Kim, Inkyoung;Brazil, Steve
    • Analyses & Alternatives
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    • v.2 no.1
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    • pp.31-69
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    • 2018
  • This study examines the role of science in resolving trade disputes. After the Great East Japan Earthquake of 11 March 2011 that not only jeopardized the people of Japan, but also put the safety of an entire region at risk, the Republic of Korea (Korea) has imposed import bans as well as increased testing and certification requirements for radioactive material on Japanese food products. Japan has challenged these restrictions at the World Trade Organizations Dispute Settlement Body (DSB). This study aims to explain how international trade agreements and previous DSB rulings have dealt with different scientific viewpoints provided by confronting parties. In doing so, it will contrast the viewpoints espoused by Korean and Japanese representatives, and then analyzes the most similar case studies previously ruled on by the DSB, including the case of beef hormones and the case of genetically modified crops including biotech corn, both between the United States and the European Communities (EC). This study finds that science is largely subordinate to national interests in the case of state decision-making within the dispute settlement processes, and science has largely been relegated to a supportive role. Due to the ambiguity and lack of truly decisive decisions in the Appellate Body in science-based trade disputes, this study concludes that the Appellate Body avoids taking a firm scientific position in cases where science is still inconclusive in any capacity. Due to the panel's unwillingness to establish expert review boards as it has the power to do, instead favoring an individual-based system so that all viewpoints can be heard, it has also developed a system with its own unique weaknesses. Similar to any court of law in which each opposing party defends its own interests, each side brings whatever scientific evidence it can to defend its position, incentivizing them to disregard scientific conclusions unfavorable to their position. With so many questions that can arise, combined with the problems of evolving science, questions of risk, and social concerns in democratic society, it is no wonder that the panel views scientific information provided by the experts as secondary to the legal and procedural issues. Despite being ruled against the EC on legal issues in two previous cases, the EC essentially won both times because the panel did not address whether its science was correct or not. This failure to conclusively resolve a debate over whose science is more scientific enabled the EC to simply fix the procedural issues, while continuing to enforce trade restrictions based on their scientific evidence. Based on the analysis of the two cases of disputes, Korea may also find itself guilty of imposing an unwarranted moratorium on Japan's fish exports, only to subsequently pass new restrictions on labelling and certification requirements because Japan may have much scientific evidence at its disposal. However, Korea might be able to create enough uncertainty in the panel to force them to rule exclusively on the legal issues of the case. This will then equip Korea, like the EC in the past, with a way of working around the ruling, by changing whatever legal procedure they need to while maintaining some, if not most, of its restrictions when the panel fails to address its case on scientific grounds.

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A Study on the Incidence of Side Effects according to the Number of Beams in Intensity-modulated Radiation Therapy for Prostate Cancer using 15 MV (15 MV를 이용한 전립샘암 세기조절 방사선치료 시 빔의 개수에 따른 부작용 발생률에 관한 연구)

  • Joo-Ah Lee
    • Journal of the Korean Society of Radiology
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    • v.17 no.3
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    • pp.481-487
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    • 2023
  • In this study, we analyzed the incidence of side effects of photoneutron dose according to the number of beams during intensity-modulated radiotherapy of prostate cancer using 15 MV. The radiation treatment plan design for intensity-modulated radiation therapy for prostate cancer was established with a prescription dose of 220 cGy per dose and a total of 7260 cGy for 33 treatments. The linear accelerator used in the experiment is Varian's True Beam STx (Varian, USA). Photoneutron dose was generated by using 15 MV energy in the planning target volume (PTV). The treatment plan was designed with IMRT 5, 7, and 9 portals using the Eclipse System (Varian Ver 10.0, USA). An optically stimulated luminescence albedo neutron dosimeter (Landauer Inc., USA) was used to measure photoneutron dose. IMRT 5 portals, 1.7 per 1,000, 7 portals, 1.8 per 1,000, 9 portals, 2.0 per 1,000 were calculated as the probability of experiencing side effects on the thyroid gland due to photoneutron dose. This study studies the risk of secondary radiation exposure dose that can occur during intensity-modulated radiation therapy, and it is considered that it will be used as useful data in relation to stochastic effects in the future.