• Title/Summary/Keyword: 조영효과 평가

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A Study on the Night Thermal-storage Power Service : Sustainability and Energy Security (심야전력제도의 문제점과 개선 방향 : 경제성·환경성·형평성 및 에너지 안보)

  • Cho, Young-Tak;Kim, Chang-Seob
    • Environmental and Resource Economics Review
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    • v.17 no.2
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    • pp.419-455
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    • 2008
  • This paper analyses the Night Thermal-storage Power Service(NTPS) from the perspective of sustainability. It investigates the economic, environmental and social aspects of NTPS, thereby reveals that NTPS triggers the inefficient use of fuel, the increase of carbon dioxide emission and the increase of cross subsidy between consumers. This paper also analyses NTPS from the perspective of energy security. It investigates how NTPS makes LNG demand volatile in winter, thus threatens our energy security. According to the analysis, NTPS directly violates two basic principles of national energy policy; Sustainability and Energy Security. To solve these problems, not only the harmonized adjustment of Heating Oil Tax and Electric Power Rates is needed to curb the rapier increase of NTPS, but also another separate policy is necessary for converting the electric heating system based on NTPS into the one based on Heating Oil.

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A Study on the Relationship between Color and Cardiovascular Parameters (색채 감성에 대한 심혈관 변수 관계성에 대한 연구)

  • Cho, Ayoung;Woo, Jincheol;Lee, Hyunwoo;Jo, Youngho;Whang, Mincheol
    • Science of Emotion and Sensibility
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    • v.20 no.4
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    • pp.127-134
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    • 2017
  • Color is a significant factor for evoking human emotion. Therefore, the effects of color have been analyzed to predict and evaluate human emotion. The purpose of this study was to measure the cardiovascular responses depending on color stimuli in order to observe differences in color-emotions. Images consisting of six colors (red, green, blue, cyan, magenta, yellow) were used as visual stimuli. 26 college or graduate students (13 males) watched the color stimuli on the monitor and scored their subjective emotion while electrocardiogram (ECG) was meausred. The effects of the color on emotion were tested using Kruskal-Wallis test and Mann-Whitney U test. The coherence ratio showed significant differences between green and magenta (p = .004), green and red (p = .006), and green and yellow (p = .004). The significant differences of cardiovascular and emotions were relevant to emotional valence. This study shows significance as an empirical study by indicating that green induces pleasant and red induces unpleasant.

Study of Facial Expression Recognition using Variable-sized Block (가변 크기 블록(Variable-sized Block)을 이용한 얼굴 표정 인식에 관한 연구)

  • Cho, Youngtak;Ryu, Byungyong;Chae, Oksam
    • Convergence Security Journal
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    • v.19 no.1
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    • pp.67-78
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    • 2019
  • Most existing facial expression recognition methods use a uniform grid method that divides the entire facial image into uniform blocks when describing facial features. The problem of this method may include non-face backgrounds, which interferes with discrimination of facial expressions, and the feature of a face included in each block may vary depending on the position, size, and orientation of the face in the input image. In this paper, we propose a variable-size block method which determines the size and position of a block that best represents meaningful facial expression change. As a part of the effort, we propose the way to determine the optimal number, position and size of each block based on the facial feature points. For the evaluation of the proposed method, we generate the facial feature vectors using LDTP and construct a facial expression recognition system based on SVM. Experimental results show that the proposed method is superior to conventional uniform grid based method. Especially, it shows that the proposed method can adapt to the change of the input environment more effectively by showing relatively better performance than exiting methods in the images with large shape and orientation changes.

A Study on the Characteristics of Alkali Silica Sol Grouting Material (알칼리성 실리카졸 지반주입재의 특성에 관한 연구)

  • Cho, Younghun;Kim, Chanki;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
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    • v.12 no.4
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    • pp.17-24
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    • 2011
  • For the purpose of cut off and ground stabilization, water glass chemical grouting method using sodium silicate has problems of weakening durability and ground water pollution because leaching was conducted when the homogel is exposed to the ground water as time elapses. The purpose of this study is to identify the effect of alkali silica sol ground injection materials, it was compared with the sodium silicate ground injection materials using water glasses. For sodium silicate and alkali silica sol by mixing each case is divided into four different specimens were made and tested. The characteristic of alkali silica sol ground injection material was analyzed by unconfined compression test and environmental impact statement of ordinary portland cement and blast furnace slag cement. Alkali silica sol specimens were made mixing A-solution and B-solution in the proportion of one on one. Through this study, alkali silica sol ground injection mixing blast furnace slag cement has excellent strength and environment-friendly.

Safety Evaluation of the Settlement Amount of the Bridge Earthwork Transition Area Using the Ground Penetrating Radar in the Soft Ground Section (연약지반 구간에서 지표투과레이더 활용한 교량 접속부 침하량 안전 평가)

  • Jung, Gukyoung;Jo, Youngkyun;Kim, Sungrae
    • Journal of the Korean GEO-environmental Society
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    • v.23 no.8
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    • pp.17-22
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    • 2022
  • To reduce the bump of bridge/earthwork transition area caused by the settlement of the soft ground during public use, the road agencies have been continuously overlay or repavement at those areas. In this study, the vehicle-mounted ground penetrating radar with 1GHz air-coupled antenna was used to estimate the settlement amount of those areas for nine bridges built in the soft ground. Results shows that it is possible to effectively measure the thickness of pavement up to a depth of 1 m on an asphalt road with ground penetrating radar technology that can inspect under the road surface. Distinctively deformation of the road surface, the variation in the thickness of the pavement measured at bridge/earth transition areas is equivalent to a minimum of 50 mm and a maximum of 600 mm, and there is a risk of cavity in the ground. The difference in the increased pavement thickness is 50~250 mm for each bridge connection, which may cause the differential settlement. In this study, by using the result of the ground penetration radar, a plan for improving drivability and maintenance of the settlement is suggested and applied to the field.

Exploring the Flexural Bond Strength of Polymer-Cement Composition in Crack Repair Applications (균열 보수용 폴리머 시멘트 복합체의 휨접착강도에 관한 연구)

  • Jo, Young-Kug
    • Journal of the Korea Institute of Building Construction
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    • v.24 no.1
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    • pp.23-34
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    • 2024
  • This research aims to assess the flexural bonding efficacy of polymer-cement composites(PCCs) in mending cracks within reinforced concrete(RC) structures. The study involved infilling PCCs into cement mortar cracks of varying dimensions, followed by evaluations of enhancements in flexural adhesion and strength. The findings indicate that the flexural bond performance of PCCs in crack repair is influenced by the cement type, polymer dispersion, and the polymer-to-binder ratio. Specifically, the use of ultra-high early strength cement combined with silica fume resulted in an up to 19.0% improvement in flexural bond strength compared to the application of ordinary Portland cement with silica fume. It was observed that the augmentation in flexural strength of cement mortar filled with PCCs was significantly more dependent on the depth of the crack rather than the width. Furthermore, PCCs not only acted as repair agents but also as reinforcement materials, enhancing the flexural strength to a certain extent. Consequently, this study concludes that PCCs formulated with ultra-high early strength cement, various polymer dispersions, silica fume, and a high polymer-to-binder ratio ranging from 60% to 80% are highly effective as maintenance materials for crack filling in practical settings.

The Impact of Entrepreneurial Self-Efficacy on the Entrepreneurial Intention of Preliminary Social Entrepreneurs and General Entrepreneurs: The Moderating Effect of Social Support (사회적기업 및 일반기업 예비 창업가의 창업효능감이 창업의도에 미치는 영향: 사회적 지지의 조절효과)

  • Cho, Young bohk;Son, Jin Hyun;Jung, Ki Bum;Lee, Na Young
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.13 no.1
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    • pp.89-104
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    • 2018
  • The purpose of this study is to examine the relation between entrepreneurial self-efficacy and entrepreneurial intention, and analyze how social support gained through social relations influences on the relation between entrepreneurial self-efficacy and entrepreneurial intention. This study outcome is as in the following. First, both general corporate and preliminary social entrepreneur are to examine that entrepreneurial self-efficacy positively influences the entrepreneurial intention. Second, in the case of the social support, it didn't influence on preliminary general corporate. And only feedback support and instrument support are related to influence on preliminary social entrepreneur among social supports. This study shall have a significance in using the result of previous studies that entrepreneurial self-efficacy influences on entrepreneurial intention by looking into moderating effect of social support, classifying general corporate and preliminary social entrepreneur who have the entrepreneurial intention.

Evaluation of Stability in the Purified Wood Vinegar and Its Hair Growth Effect (목초액의 안정성 및 모발 성장 촉진 효과)

  • Cho, Young-Ho;Lee, Ju-Yeon;Lee, Jong-Hwa;Cho, Jae-Su;Lee, Gye-Won
    • Journal of Life Science
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    • v.19 no.10
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    • pp.1389-1395
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    • 2009
  • Generally, it takes a long time to purify wood vinegar, and it contains toxic compounds such as tar, methanol, phenol and benzopyrene. To reduce the toxicity of wood vinegar itself, we have developed a new purification method of wood vinegar using an oxidation-cohesion reaction and distillation with an active carbon. We have investigated the physico-chemical change (pH, specific gravity, refractive index and dissolved tar), the change of amount of toxic compounds (carbonyl group, phenol, benzopyrene and residual solvents) and organic acids (formic acid (FA), acetic acid (AA), propionic acid (PA)) of the purified wood vinegar under the long term and accelerated storage conditions. Also, we have evaluated the effect of the purified wood vinegar on hair growth using an alopecia model of C57BL/6 mice. As a result, we could find out that the purified wood vinegar was stable and remained without decay under the storage conditions and benzopyrene, a carcinogenic agent, was not detected in the purified wood vinegar. After topical treatment of the purified wood vinegar solution or minoxidil (MXD) for 2 weeks to dorsal skin, the hair regrowth of the mice accelerated faster than that of the control, with no clinical signs. In conclusion, we could suggest a guideline for quality control of process to reduce the toxic compounds in wood vinegar and it might be a useful hair growth promoter in the treatment of baldness or alopecia.

Evaluation of Inflammatory Disease in the Nasal Cavity and Paranasal Sinuses using CT in Dogs and Cats (개와 고양이에서 컴퓨터단층촬영술을 이용한 비강의 염증성 질병 평가)

  • Choi, Ho-Jung;Lee, Ki-Ja;Park, Seong-Jun;Jeong, Seong-Mok;Song, Kun-Ho;Lee, Young-Won
    • Journal of Veterinary Clinics
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    • v.27 no.1
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    • pp.42-45
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    • 2010
  • Inflammatory sinonasal disease was diagnosed in five dogs and two cats with clinical signs of nasal discharge and epistaxis. Survey radiography and CT were performed in all of patients. CT scan of the rostral cranium was performed with a thickness of 2 or 5 mm. Nasal cytology and culture from nasal smear were performed immediately after CT examination. Remarkable increase of opacity in the nasal cavities and frontal sinuses was observed in only 3 cases. On CT images, the cavitating lesions were isodense in nasal cavity (7 cases), frontal sinuses (3 cases), and nasopharynx (2 cases) with destruction of the nasal septum (4 cases), maxillary turbinates (5 cases), maxilla (3 cases), and hard palate (3 cases). The lesions were enhanced after intravenous contrast administration in 5 cases and were not enhanced in 2 cases. Inflammatory cells were observed in nasal cytology. Most of the cultures from nasal smear were bacteria. CT is useful to diagnose sinonasal disease and is more accurate in demonstrating the extent and character of lesions of nasal cavity than radiography.

4-week dose range finding toxicity test of Magnoliae Flos extract in Sprague-Dawley rats (Sprague-Dawley 랫드를 이용한 신이 추출물의 4주 반복 용량 결정 독성시험)

  • Park, Ju-Hyoung;Ahn, Eun-Kyung;Park, Kitae;Hwang, Min Hee;Cho, Young-Rak;Lee, Dong-Ryung;Choi, Bong-Keun;Oh, Joa Sub
    • Journal of Applied Biological Chemistry
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    • v.65 no.1
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    • pp.43-48
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    • 2022
  • Medicinal herb demonstrated in many pharmacological effects and recognized to be safe has been used for a long time. However, side effects including safety of medicinal herb have not been identified yet. The aim of the study was to estimate safety evaluation of Magnoliae Flos used for the treatment of pain, rhinitis, and pneumonia in Korea, China and Japan through four-week dose range finding toxicity test in male and female Sprague-Dawley rats. Magnoliae Flos was orally administered to male and female SD rats once a day for 28 days at 1,500 and 3,000 mg/kg. The safety evaluation was determined to examine clinical signs, mortality, body weight, food intake, hematology, serum biochemistry and relative organ weights and there were no significant changes related toxicity. Consequently, these findings indicates that Magnoliae Flos did not show any side effects including toxicity in dose range finding toxicity test and the no observed adverse effect level for Magnoliae Flos was estimated as more than 3,000 mg/kg.