• Title/Summary/Keyword: Reflection Rate

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Photocatalytic Activity of Hierarchical N doped TiO2 Nanostructures

  • Naik, Brundabana;Kim, Sun Mi;Jung, Chan Ho;Park, Jeong Young
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.669-669
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    • 2013
  • Hierarchical N doped TiO2 nanostructured catalyst with micro, meso and macro porosity have been synthesized by a facile self-formation route using ammonia and titanium isopropoxide precursor. The samples were calcined in different calcination temperature ranging from $300^{\circ}C$ to $800^{\circ}C$ at slow heating rate ($5^{\circ}C$/min) and designated as NHPT-300 to NHPT-800. $TiO_2$ nanostructured catalyst have been characterized by physico-chemical and spectroscopy methods to explore the structural, electronic and optical properties. UV-Vis diffuse reflectance spectra confirmed the red shift and band gap narrowing due to the doping of N species in TiO2 nanoporous catalyst. Hierarchical macro porosity with fibrous channel patterning was observed (confirmed from FESEM) and well preserved even after calcination at $800^{\circ}C$, indicating the thermal stability. BET results showed that micro and mesoporosity was lost after $500^{\circ}C$ calcination. The photocatalytic activity has been evaluated for methanol oxidation to formaldehyde in visible light. The enhanced photocatalytic activity is attributed to combined synergetic effect of N doping for visible light absorption, micro and mesoporosity for increase of effective surface area and light harvestation, and hierarchical macroporous fibrous structure for multiple reflection and effective charge transfer.

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Multi-View Wyner-Ziv Video Coding Based on Spatio-temporal Adaptive Estimation (시공간 적응적인 예측에 기초한 다시점 위너-지브 비디오 부호화 기법)

  • Lee, Beom-yong;Kim, Jin-soo
    • The Journal of the Korea Contents Association
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    • v.16 no.6
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    • pp.9-18
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    • 2016
  • This paper proposes a multi-view Wyner-Ziv Video coding scheme based on spatio-temporal adaptive estimation. The proposed algorithm is designed to search for a better estimated block with joint bi-directional motion estimation by introducing weights between temporal and spatial directions, and by classifying effectively the region of interest blocks, which is based on the edge detection and the synthesis, and by selecting the reference estimation block from the effective motion vector analysis. The proposed algorithm exploits the information of a single frame viewpoint and adjacent frame viewpoints, simultaneously and then generates adaptively side information in a variety of closure, and reflection regions to have a better performance. Through several simulations with multi-view video sequences, it is shown that the proposed algorithm performs visual quality improvement as well as bit-rate reduction, compared to the conventional methods.

A Study on the Illuminance Measurement and Improvement of Public Libraries in Daegu City (공공도서관 조도분석 및 개선방안 연구 - 대구지역을 중심으로 -)

  • Yoon, Hee-Yoon
    • Journal of Korean Library and Information Science Society
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    • v.48 no.4
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    • pp.1-20
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    • 2017
  • The most important identity of public library is local public goods that guarantee access and use of knowledge and information of local residents. To justify this, the library must create an optimal lighting environment. Particularly, since the perception rate of information through vision is over 80%, it is necessary to secure proper illuminance. This study measured the illuminance level of public libraries in Daegu. Based on the results, this study suggested a desirable illuminance level for each space and proposed plans to secure and maintain proper illuminance(prospective revision of the KS A 3011, setting the illuminance range for each space of the local government, replacing the existing lighting fixtures with LED, enhance supervision of lighting management, establishment of basic principles for proper lighting and detailed plans for each space of the library, investigation and reflection on users' complaints and satisfaction, etc.)

The study on development of easily chewable and swallowable foods for elderly

  • Kim, Soojeong;Joo, Nami
    • Nutrition Research and Practice
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    • v.9 no.4
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    • pp.420-424
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    • 2015
  • BACKGROUND/OBJECTS: When the functions involved in the ingestion of food occurs failure, not only loss of enjoyment of eating, it will be faced with protein-energy malnutrition. Dysmasesis and difficulty of swallowing occurs in various diseases, but it may be a major cause of aging, and elderly people with authoring and dysmasesis and difficulty of swallowing in the aging society is expected to increase rapidly. SUBJECTS/METHODS: In this study, we carried out a survey targeting nutritionists who work in elderly care facilities, and examined characteristics of offering of foods for elderly and the degree of demand of development of easily chewable and swallowable foods for the elderly who can crush foods and take that by their own tongues, and sometimes have difficulty in drinking water and tea. RESULTS: In elderly care facilities, it was found to provide a finely chopped food or ground food that was ground with water in a blender for elderly with dysmasesis. Elderly satisfaction of provided foods is appeared overall low. Results of investigating the applicability of foods for elderly and the reflection will of menus, were showed the highest response rate in a gelification method in molecular gastronomic science technics, and results of investigating the frequent food of the elderly; representative menu of beef, pork, white fish, anchovies and spinach, were showed Korean barbecue beef, hot pepper paste stir fried pork, pan fried white fish, stir fried anchovy, seasoned spinach were the highest offer frequency. CONCLUSIONS: This study will provide the fundamentals of the development of easily chewable and swallowable foods, gelification, for the elderly. The study will also illustrate that, in the elderly, food undergone gelification will reduce the risk of swallowing down to the wrong pipe and improve overall food preference.

Classifying Color Codes Via k-Mean Clustering and L*a*b* Color Model (k-평균 클러스터링과 L*a*b* 칼라 모델에 의한 칼라코드 분류)

  • Yoo, Hyeon-Joong
    • The Journal of the Korea Contents Association
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    • v.7 no.2
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    • pp.109-116
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    • 2007
  • To reduce the effect of color distortions on reading colors, it is more desirable to statistically process as many pixels in the individual color region as possible. This process may require segmentation, which usually requires edge detection. However, edges in color codes can be disconnected due to various distortions such as dark current, color cross, zipper effect, shade and reflection, to name a few. Edge linking is also a difficult process. In this paper, k-means clustering was performed on the images where edge detectors failed segmentation. Experiments were conducted on 311 images taken in different environments with different cameras. The primary and secondary colors were randomly selected for each color code region. While segmentation rate by edge detectors was 89.4%, the proposed method increased it to 99.4%. Color recognition was performed based on hue, a*, and b* components, with the accuracy of 100% for the successfully segmented cases.

A Journey to Action Research in a Clinical Nursing Context (임상간호현장에서의 실행연구 여정)

  • Jang, Keum Seong;Kim, Heeyoung;Kim, Eun A;Kim, Yun Min;Moon, Jeong Eun;Park, Hyunyoung;Song, Mi-Ok;Baek, Myeong
    • Journal of Korean Academy of Nursing Administration
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    • v.19 no.1
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    • pp.95-107
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    • 2013
  • Purpose: The purpose of this study was to examine the effectiveness of Action Research (AR) approach in nursing. Methods: Participants were 64 perioperative nurses recruited from C hospital in Gwangju, Korea. The nurses were engaged in the project through 2 cycles of planning, acting, observing, and reflecting. A mixed-methods design was used to examine changes in participants and their knowledge management practice. Quantitative data were analyzed using SPSS 20.0 program and qualitative reflection data underwent content analysis. Results: During the project, participants developed standardized pre-operative checklists and opened an Internet Cafe to better manage their perioperative nursing information. At the end of the project, there was a significant increase in nurses' knowledge management (p=.015) and the rate of surgical material prescription errors decreased from 8.0% to 2.9%. Core AR project team members' teamwork skills and organizational commitment increased significantly (p=.040, p=.301, respectively). The main themes that emerged from the qualitative data were learning how to solve problems in practice, facilitating team activities through motivation, barriers of large participation, and rewarded efforts and inflated expectations. Conclusion: The AR project contributed to empowering participants to solve local problems. AR is a useful methodology to promote changes in practices and research participants.

Growth and characterization of bulk GaN single crystals by basic ammonothermal method (Basic 암모노써멀 방법에 의한 벌크 GaN 단결정의 성장 및 특성)

  • Shim, Jang Bo;Lee, Young Kuk
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.26 no.2
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    • pp.58-61
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    • 2016
  • Bulk GaN crystals were grown by the basic ammonothermal method. The c-plane GaN templates grown by hydride vapor phase epitaxy were used as seed crystals and sodium metal, amide, and azide were added as a mineralizer. The growth conditions are at temperatures from $500{\sim}600^{\circ}C$ and pressures from 2~3 kbar. The growth rate for the c-axis was increased with increasing the operating pressure. Average dislocation density was measured $1{\times}10^5/cm^2$ by the cathodoluminescence measurement. The full-width at half-maximum of the X-ray diffraction rocking curve for (002) reflection was approximately 270 arcsec for Ga face and 80 arcsec for N face.

Research on Lighting Performance Evaluation for Different Curvature Reflection Rate in Residential Space (주거공간 내 광선반 곡률 형태에 따른 채광성능평가 연구)

  • Oh, Sangwon;Lee, Heangwoo;Kim, Yongseong;Seo, Janghoo
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.6
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    • pp.328-336
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    • 2015
  • Currently, 22% of the total energy consumption of buildings in Korea is used for lighting. Light-shelves have garnered attention as a way to reduce consumption, but there are few studies on the types of curve and curvature, which limits the improvement of light-shelf performance and its design. This study constructed a test bed of actual residential types to evaluate the performance. Outcomes of light usage, according to variables of light-shelves, were used as indicators of performance evaluation. The results are as follows:1) Performance evaluation was conducted on flat-type light-shelves to verify performance of curvature-shelves, which are movable with a width of 200 mm, and the most ideal angle and specification per solar term are calculated. 2) The (-) shaped curvature contributed to a reduction in energy consumption and an improvement of evenness. 3) In case of light-shelves with (-) shaped curvature, an increased angle not exceeding $80^{\circ}$ of the arc contributed to an improvement of light penetration. 4) Appropriate specifications of curved light-shelves include movable types with widths of 200 mm, and angle ranges of $20^{\circ}{\sim}60^{\circ}$. 5) Light energy consumption of a movable light-shelf with curvature and width of 200 mm were reduced by 17% and 7.8% compared to a $0^{\circ}$ fixed and a movable light-shelf, respectively.

Evaluations of Mn-Ni-Co type thermistor thin film for thermal infrared sensing element (열형 적외선 센싱소자용 Mn-Ni-Co계 써미스터 박막 특성 평가)

  • 전민석;최덕균
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.13 no.6
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    • pp.297-303
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    • 2003
  • Mn-Ni-Co type thin films were prepared at various conditions by a rf magnetron sputtering system. At the condition. or substrate temperature of $300^{\circ}C$ and $Ar/O_2$= 10/0, a cubic spinel phase was obtained. When oxygen was included in process gas, a cubic spinel phase was not formed even after the thermal annealing at $900^{\circ}C$. The thermistor thin film had no other elements except Mn, Ni and Co. The infrared reflection spectra of the thermistor thin films showed that the films had somewhat high reflectance for incoming infrared ray with some angle. The etch rate of the thermistor thin films was about 63nm/min at a condition of DI water : $HNO_3$: HCl = 60 : 30 : 10 vol%. The B constant and temperature coefficient of resistance of the thermistor thin films were 3500 K and -3.95 %/K, respectively. The voltage responsivity of the thermistor thin film infrared sensor was 108.5 V/W and its noise equivalent power and specific detectivity were $5.1\times 10^{-7}$ W/$Hz^{-1/2}$ and $0.2\times 10^6$cm $Hz^{1/2}$/W, respectively.

A Study on the Optimization of Semantic Relation of Author Keywords in Humanities, Social Sciences, and Art and Sport of the Korea Citation Index (KCI) (한국학술지인용색인(KCI)의 인문학, 사회과학, 예술체육 분야 저자키워드의 의미적 관계 유형 최적화 연구)

  • Ko, Young Man;Song, Min-Sun;Lee, Seung-Jun
    • Journal of the Korean Society for Library and Information Science
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    • v.49 no.1
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    • pp.45-67
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    • 2015
  • The purpose of this study is to analyse the semantic relations of terms in STNet, a structured terminology dictionary based on author keywords of humanities, social sciences, and art and sport in the Korea Citation Index (KCI) and to describe the procedure for optimizing the relation types and specifying the name of relationships. The results indicate that four logical criteria, such as creating new names for relationships or limitation of typing the relationship by the appearance frequency of same type, consideration of direction of relationship, reflection to accept the existing name of relationships, are required for the optimization of the typing and naming the relationships. We applied these criteria to the relationships in the class "real person" of STNet and the result shows that 1,135 out of 1,743 uncertain relationships such as RT, RT_X or RT_Y are specified and clarified. This rate of optimization with ca. 65% represents the usefulness of the criteria applicable to the cases of database construction and retrieval.