• Journal of the Korean Geotechnical Society
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• 제25권1호
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• pp.41-54
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• 2009

The purpose of this research is to introduce the new temporary earth retaining wall system using landslide stabilizing piles. This system is a self-supported retaining wall (SSR) without installing supports such as tiebacks, struts and rakers. The SSR is a kind of gravity structures consisting of twin parallel lines of piles driven below excavation level, tied together at head of soldier piles and landslide stabilizing piles by beams. In order to investigate applicability and safety of this system, a series of experimental model tests were carried out and the obtained results are presented and discussed. Furthermore, the measured data from seven different sites on which the SSR was used for excavation were collected and analyzed to investigate the characteristic behavior lateral wall movements associated with urban excavations in Korea. It is observed that lateral wall movements obtained from the experimental model is in good agreement with the general trend observed by in site measurements.

• Journal of the Korean Home Economics Association
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• 제46권9호
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• pp.99-112
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• 2008

The increasing rate of obesity in school aged children has become a conspicuous social phenomenon in Korea. This has been linked to greater economic growth, increasingly westernized dietary habits, and a consumer driven society. Given that obesity can lead to social exclusion or unfavorable attention by other students in a school setting, the design of plus-size garments have become important for effective appearance management skills. This research aimed to establish a somatotype database for obese school boys, aged 10 to 12, in order to develop a sizing system for plus-size upper garments. In order to measure somatotype of average and obese school boys, five categories were recorded; height, obesity, length of trunk, thickness of neck and chest. For obese boys, subcutaneous fat thickness and position of B.P/shoulder point factors were recorded. Obesity factor was subdivided into overall and specific ones, and while the deviation of obese body types was severe compared to the average type. Obese body type showed significantly higher measurements in width, girth, thickness. This is linked to the fact that the frequency ratio of obesity increases with age. Stature and chest were chosen as control dimensions for boys' wear. As crosstabulation of stature(5cm interval) and chest girth(2, 3 and 4cm), and stature(5cm interval)/chest girth(3cm interval) sizing system showed, the most effective cover ratio and adaptability to the data distribution $25{\sim}75$ quartile. Based on the findings, 10 sizes were formulated for average body type, while 18 sizes were formulated for obese type, whose size cover ratios were 48% and 62.9%, respectively. The primary ranges of stature were $145cm{\sim}150cm$, while those of chest girth were $79{\sim}82cm$. Each size was declared as "chest-somatotype{A(average)/O(obesity)-stature". This study proposed a plus-size upper garment sizing systems for obese boys, accompanied with reference measurements for suit, casual wear and underwear. The finding showed that the two systems were totally separate and not overlapping, meaning that plus-size sizing system is essential for obese school boys. The obesity type system had more size and wider range specs.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• 제15권1호
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• pp.245-251
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• 2015

In this paper, we present a design of PWM-controlled driving device for backlights in LED systems. The system can control either the brightness of the entire screen of backlights of LCD driven by LED or illumination or contrast of each partial segment of the entire screen. The PWM-controlled driving device includes the shift register that shifts the series data according to the clock signal prior to the generation of parallel data. It is also is comprised of a number of registers, a number of counters, a number of comparators, and a number of synchronizing gates (producing the PWM-controlled signals). The proposed device for backlights in LED systems can generate the PWM-controlled signal with a high degree of resolution without the increase of clock frequency. It also contains the PWM-controlled circuit that disperses and restrains the quantized noise.

• Quality Improvement in Health Care
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• 제7권2호
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• pp.204-216
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• 2000

Background : There has been a concern that the quality of care provided to end-stage renal disease (ESRD) patients in the United States may not be as good as recommended. This paper illustrates a composite measure to assess, the quality of care received by ESRD patients undergoing in-center hemodialysis by incorporating outcomes for 4 major treatment areas. The 4 treatment areas are: dialysis treatments, anemia control, nutritional management, and blood pressure control. Methods : The major data source for the study was the United States Renal Data System (USRDS) Dialysis Morbidity and Mortality Study Wave 1 (DMMS-1) d Sixteen categories of a composite quality indicator were constructed by combining 4 dichotomous variables (16=2*2*2*2). representing the optimal vs. less than optimal level of outcome for each of the 4 treatment outcome measure respectively. Optimal outcome level for each treatment area was defined based on the recommendation from the National Kidney Foundation: (a) delivered dialysis doses (Kt/V) ${\geq}$ 1.2; (b) hematocrit level ${\geq}$ 30%; (c) serum albumin concentration ${\geq}$ 3.8g/dl ; and (d) blood pressure of <140 / <90mmHg. The 16 quality indicator were ranked according to their relative quality weights, which were estimated from its association with the relative risk of survival, adjusting for patient's baseline severity and dialysis facility characteristics. Results : Out of the entire sample of 2,179 patients, only 229 (10%) meet th recommended outcome levels for all 4 treatment areas. Overall, the study patients were distributed evenly over the 16 quality indicators, indicating a great variation in the quality of ESRD care. It appears that the rank of the 16 quality-indicators is driven by serum albumin concentration, suggesting that serum albumin concentration may be the most powerful predictor of ESRD patient survival among the 4 outcome measures. Conclusion : The developed quality indicator has the advantage of describin a range of care for dialysis patients and thus providing a more complete picture of care as compared to previous studies that have focused on only single or few components of the ESRD care.

• Nuclear Engineering and Technology
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• 제45권6호
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• pp.759-766
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• 2013

As passive safety features for nuclear power plants receive increasing attention, various studies have been conducted to develop safety systems for 3rd-generation (GEN-III) nuclear power plants that are driven by passive systems. The Passive Auxiliary Feedwater System (PAFS) is one of several passive safety systems being designed for the Advanced Power Reactor Plus (APR+), and extensive studies are being conducted to complete its design and to verify its feasibility. Because the PAFS removes decay heat from the reactor core under transient and accident conditions, it is necessary to evaluate the heat removal capability of the PAFS under hypothetical accident conditions. The heat removal capability of the PAFS is strongly dependent on the heat transfer at the condensate tube in Passive Condensation Heat Exchanger (PCHX). To evaluate the model of heat transfer coefficient for condensation, the Multi-dimensional Analysis of Reactor Safety (MARS) code is used to simulate the experimental results from PAFS Condensing Heat Removal Assessment Loop (PASCAL). The Shah model, a default model for condensation heat transfer coefficient in the MARS code, under-predicts the experimental data from the PASCAL. To improve the calculation result, The Thome model and the new version of the Shah model are implemented and compared with the experimental data.

• Smart Structures and Systems
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• 제26권2호
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• pp.175-184
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• 2020

Conventional Monte Carlo simulation-based methods for seismic risk assessment of water networks often require excessive computational time costs due to the hydraulic analysis. In this study, an Artificial Neural Network-based surrogate model was proposed to efficiently evaluate the flow-based system reliability of water distribution networks. The surrogate model was constructed with appropriate training parameters through trial-and-error procedures. Furthermore, a deep neural network with hidden layers and neurons was composed for the high-dimensional network. For network training, the input of the neural network was defined as the damage states of the k-dimensional network facilities, and the output was defined as the network system performance. To generate training data, random sampling was performed between earthquake magnitudes of 5.0 and 7.5, and hydraulic analyses were conducted to evaluate network performance. For a hydraulic simulation, EPANET-based MATLAB code was developed, and a pressure-driven analysis approach was adopted to represent an unsteady-state network. To demonstrate the constructed surrogate model, the actual water distribution network of A-city, South Korea, was adopted, and the network map was reconstructed from the geographic information system data. The surrogate model was able to predict network performance within a 3% relative error at trained epicenters in drastically reduced time. In addition, the accuracy of the surrogate model was estimated to within 3% relative error (5% for network performance lower than 0.2) at different epicenters to verify the robustness of the epicenter location. Therefore, it is concluded that ANN-based surrogate model can be utilized as an alternative model for efficient seismic risk assessment to within 5% of relative error.

• Journal of the Korea Institute of Information and Communication Engineering
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• 제25권1호
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• pp.36-43
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• 2021

In this research, the accuracy of YOLO v3 algorithm in object detection during AGV (Automated Guided Vehicle) operation was investigated. First of all, AGV with 2D LiDAR and stereo camera was prepared. AGV was driven along the route scanned with SLAM (Simultaneous Localization and Mapping) using 2D LiDAR while front objects were detected through stereo camera. In order to evaluate the accuracy of YOLO v3 algorithm, recall, AP (Average Precision), and mAP (mean Average Precision) of the algorithm were measured with a degree of machine learning. Experimental results show that mAP, precision, and recall are improved by 10%, 6.8%, and 16.4%, respectively, when YOLO v3 is fitted with 4000 training dataset and 500 testing dataset which were collected through online search and is trained additionally with 1200 dataset collected from the stereo camera on AGV.

• Proceedings of the Korean Society of Crop Science Conference
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.135-135
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• 2017

The Gramene database (http://www.gramene.org) is a powerful online resource for agricultural researchers, plant breeders and educators that provides easy access to reference data, visualizations and analytical tools for conducting cross-species comparisons. Learn the benefits of using Gramene to enrich your lectures, accelerate your research goals, and respond to your organismal community needs. Gramene's genomes portal hosts browsers for 44 complete reference genomes, including crops and model organisms, each displaying functional annotations, gene-trees with orthologous and paralogous gene classification, and whole-genome alignments. SNP and structural diversity data, available for 11 species, are displayed in the context of gene annotation, protein domains and functional consequences on transcript structure (e.g., missense variant). Browsers from multiple species can be viewed simultaneously with links to community-driven organismal databases. Thus, while hosting the underlying data for comparative studies, the portal also provides unified access to diverse plant community resources, and the ability for communities to upload and display private data sets in multiple standard formats. Our BioMart data mining interface enable complex queries and bulk download of sequence, annotation, homology and variation data. Gramene's pathway portal, the Plant Reactome, hosts over 240 pathways curated in rice and inferred in 66 additional plant species by orthology projection. Users may compare pathways across species, query and visualize curated expression data from EMBL-EBI's Expression Atlas in the context of pathways, analyze genome-scale expression data, and conduct pathway enrichment analysis. Our integrated search database and modern user interface leverage these diverse annotations to facilitate finding genes through selecting auto-suggested filters with interactive views of the results.

• Korean Journal of Radiology
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• 제25권6호
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• pp.565-574
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• 2024

Objective: To evaluate the safety and clinical outcomes of the Passeo-18 Lux drug-coated balloon (DCB) in endovascular revascularization procedures under real-world conditions in a Korean population with atherosclerotic disease of the infrainguinal arteries, including below-the-knee (BTK) arteries. Materials and Methods: Eight institutions in the Republic of Korea participated in this prospective, multicenter, single-arm, post-market surveillance study. Two hundred patients with Rutherford class 2-5 peripheral arterial disease and infrainguinal lesions suitable for endovascular treatment were competitively enrolled. Data were collected at baseline, the time of intervention, discharge, and 1-, 6-, 12-, and 24-month follow-up visits. The primary safety endpoint was freedom from major adverse events (MAE) within 6 months (except when limiting the time frame for procedure- or device-related mortality to within 30 days), and the primary effectiveness endpoint was freedom from clinically driven target lesion revascularization (CD-TLR) within 12 months after the procedure. Results: A total of 197 patients with 332 target lesions were analyzed. Two-thirds of the patients had diabetes mellitus, and 41.6% had chronic limb-threatening ischemia. The median target lesion length was 100 mm (interquartile range: 56-133 mm). Of the target lesions, 35.2% were occlusions, and 14.8% were located in the BTK arteries. Rate of freedom from MAE was 97.9% at 6 months, and the rate of freedom from CD-TLR was 95.0% and 92.2% at 12 and 24 months, respectively. Subgroup analysis of 43 patients and 49 target lesions involving the BTK arteries showed rate of freedom from MAE of 92.8% at 6 months and rates of freedom from CD-TLR of 88.8% and 84.4% at 12 and 24 months, respectively. Conclusion: The results of the present study, including the BTK subgroup analysis, showed outcomes comparable to those of other DCB studies, confirming the safety and effectiveness of Passeo-18 Lux DCB in the Korean population.

• International Journal of High-Rise Buildings
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• 제10권4호
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• pp.345-364
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• 2021

Developments in the understanding of fire behaviour for large open-plan spaces typical of tall buildings have been greatly outpaced by the rate at which these buildings are being constructed and their characteristics changed. Numerous high-profile fire-induced failures have highlighted the inadequacy of existing tools and standards for fire engineering when applied to highly-optimised modern tall buildings. With the continued increase in height and complexity of tall buildings, the risk to the occupants from fire-induced structural collapse increases, thus understanding the performance of complex structural systems under fire exposure is imperative. Therefore, an accurate representation of the design fire for open-plan compartments is required for the purposes of design. This will allow for knowledge-driven, quantifiable factors of safety to be used in the design of highly optimised modern tall buildings. In this paper, we review the state-of-the-art experimental research on large open-plan compartment fires from the past three decades. We have assimilated results collected from 37 large-scale compartment fire experiments of the open-plan type conducted from 1993 to 2019, covering a range of compartment and fuel characteristics. Spatial and temporal distributions of the heat fluxes imposed on compartment ceilings are estimated from the data. The complexity of the compartment fire dynamics is highlighted by the large differences in the data collected, which currently complicates the development of engineering tools based on physical models. Despite the large variability, this analysis shows that the orders of magnitude of the thermal exposure are defined by the ratio of flame spread and burnout front velocities (V_S / V_BO), which enables the grouping of open-plan compartment fires into three distinct modes of fire spread. Each mode is found to exhibit a characteristic order of magnitude and temporal distribution of thermal exposure. The results show that the magnitude of the thermal exposure for each mode are not consistent with existing performance-based design models, nevertheless, our analysis offers a new pathway for defining thermal exposure from realistic fire scenarios in large open-plan compartments.