• Title/Summary/Keyword: Building materials

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The research about the physical properties and flexural strength changed by Low Temperature Degradation of TZP monolithic all-ceramic crown block to make bio-prosthetic dentistry (치과용 생체보철물 제작을 위한 TZP 단일구조 전부도재관 블럭의 물성과 저온열화 후 굴곡강도에 관한 연구)

  • Lee, Jong-Hwa;Park, Chun-Man;Song, Jae-Sang;Lim, Si-Duk;Kim, Jae-Do;Kim, Byung-Sik;Hwang, In-Whan;Lee, Sung-Kuk
    • Journal of Technologic Dentistry
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    • v.34 no.2
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    • pp.83-93
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    • 2012
  • Purpose: The objective of this study is to find out physical properties and the flexural strength changed by the low temperature degradation of the block which is needed to make bio-prosthetic dentistry which is better than feldspar affiliated ceramic made by building up ceramic powder and also to apply this to the clinical use of zirconia monolithic all-ceramic crown. Methods: Flexural strength of each sample was evaluated before and after the Low Temperature Degradation, and physical properties of the Tetra Zirconia Block containing 3mol % was evaluated as well. The average and standard deviation of each experimental group were came out of the evaluation. Statistical package for social science 18.0 was used for statistics. Results: The average density of the monolithic all-ceramic crown was $6.0280{\pm}0.0147g/cm$, the relative density was 99.01 %. When the sample was sintered at $1480^{\circ}C$ the diameter of average particle was $396.62{\pm}33.71nm$. All the samples had no monolithic peak after XRD evaluation but only had tetragonal peak. There were statistically significant differences in the result of flexural strength of the samples evaluated after and before the low temperature degradation, the flexural strength before the low temperature degradation was $1747.40{\ss}{\acute{A}}$, at the temperature of $130^{\circ}C$ the flexural strength after the low temperature degradation was 1063.99MPa (p<0.001). There was statistically significant difference in the result of strength of 1020.07MPa after the low temperature degradation at the temperature of $200^{\circ}C$ (p<0.001). Conclusion: The block which was made for this evaluation possesses such an excellent strength among dental restorative materials that it is thought to have no problems to use for tetragonal zirconia polycrystal.

Combustion Characteristics of the Quercus variabilis and Zelkova Serrata Dried at Room Temperature (자연 건조된 굴참나무와 느티나무의 연소특성)

  • Chung, Yeong-Jin;Kwon, In-Kyu
    • Journal of Korean Society of Forest Science
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    • v.99 no.1
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    • pp.96-101
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    • 2010
  • One of the restriction of wood as building material is its combustibility. The purpose of this paper is to examine the combustion properties of the quercus variabilis and zelkova serrata which are dried at room temperature and meet the desirable characteristics for use of construction materials. The cone calorimeter (ISO 5660-1) was used to determine the heat release rate (HRR) and fire smoke index, as well as CO production and smoke obscuration. The $HRR_{mean}$ 77.94 kW/$m^2$ of the quercus variabilis at 50 kW/$m^2$ was high in comparison with $HRR_{mean}$ 13.06 kW/$m^2$ for the zelkova serrata. Furthermore, the quercus variabilis has high specific extinction area ($SEA_{mean}$), 41.11 $m^2$/kg compared with $SEA_{mean}$ 9.23 $m^2$/kg of zelkova serrata. Thease results are depend on the density of tested wood species. In addition, the quercus variabilis has high CO production rate compared with that of zelkova serrata. Also, zelkova serrata showed an increase of retardant properties attributed to char formation compared with that of quercus variabilis.

Current Status and Future Directions on the Management of the Korean Standards (KS): Woods, Pulp and Papers (목재 및 펄프·제지 분야 한국산업표준(KS)의 운영현황과 방향)

  • Shin, Hyun-Kyeong;Choi, Yong-Seok;Kim, Keon-Ho;Eom, Chang-Deuk;Park, Joo-Saeng;Shim, Kug-Bo
    • Journal of Korean Society of Forest Science
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    • v.107 no.2
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    • pp.205-217
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    • 2018
  • This study aims to review the standard operation status on wood, pulp and paper industry in Korea according to the industry standardization law which has been revised for strengthening expertise of relevant department and to propose a management strategy of Korean Standards (KS) in figure. Korea Forest Service (KFS) is the responsible department of managing KS on the wood, pulp and paper industry from 2015, and currently opertates three expert committees (wood and wooden construction, wood-based materials, pulp and paper) and wood and paper industry council to review 426 standards. To support an improvement of technical competency and securement of marketability of Korean wood industry, it is about time to review the standards and to develop practical standards since it is managed by specialized department. For this purpose, it is necessary to establish a systematic approach on the management of KS, based on thorough analysis of current KS. To remove possible technical barrier on trade due to the differences of standards between countries, the conformity with international standards is necessary. Also, for sustainability of standard management system, training specialists and building their capability is essential.

A Study on the Sustainable Fashion Design by Organic Cotton (오가닉 코튼[Organic Cotton]을 이용한 지속가능한 패션디자인)

  • Kim, Soo-Hyun;Lee, Jae-Jung;Chung, Hyun-Sook
    • Journal of the Korean Society of Costume
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    • v.57 no.2 s.111
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    • pp.115-131
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    • 2007
  • By the turn of the century, our society has been gradually more interested in environmental problems than any other time. Ecological change spurred by industrial pollution is occurring beyond the borders of nations, and has emerged as a global issue. Such change is resulting in exhaustion of natural resources and energy, and serious climatic change. In this study, main focus regarding the process of the fashion product design system was placed on the sustainable fashion design of organic cotton as a positive and alternative suggestion. It is expected that the results of this study contribute to the fashion design planning not only for future generation but also for the present time. This study researched on brands that produced their fashion products using organic cotton. The following cases proved to possess sustainability in their product system. The results of this study can be summarized as follows: Firstly, sustainable design in organic cotton products has been a progressive ere-design in 2000s. It is mainly focus concerned with recycling and re-use of materials to protect environment. It is not chemical dependant and takes a particular care in eliminating waste water and energy in the dyeing process. It is an environmentally sustainable design better than all the other design processes. Secondly, it is a design that cares for the common good of society and the global system of fair trading. The fair trading of organic cotton products induced a change in the structure of production system, while defending human rights. It also gave benefits by promoting development in local society and progress in traditional skills. Not to mention that it contributed to building up the concept of transparency in the global economic system. Lastly, the brands emphasize their social responsibility and management ethics to observe environmental policy which is established to protect our nature and people. Their public information reminds customers of the importance of protecting the environment from diverse pollution. Moreover, they hold social events to promote public awareness for environmental Issues. This study dealt only with the organic cotton, a small subset of the subject of sustainable design. It can be extended and applied to various other sustainable fashion design as a solution for global environmental issues.

『Bonchojeonghwa(本草精華)』, Medical Historical Approach to Bibliographic Notes (『본초정화(本草精華)』의 해제(解題)에 관한 역사학적(醫史學的) 접근)

  • Kim, Hong-Kyoon
    • The Journal of Korean Medical History
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    • v.24 no.2
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    • pp.25-55
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    • 2011
  • The currently existing "Bonchojeonghwa (本草精華)" is a manuscript without the preface and the epilogue, composed of 2 books in 2 volumes. This book is a quintessence of knowledge on science of medicinal ingredients (medicinal phytology I herbal science) as well as an trial of new development in Chosun medical science. I.e. this book includes surprising change representing medical science in Chosun dynasty as a single publication on science of medicinal ingredients. It holds a value essential to clinician as a specialized book in medicinal ingredients, and Includes richer content on medicinal ingredients than any other books published before. In addition, it is away from boring list-up of superfluous knowledge as seen in "Bonchokangmok(本草綱目)" published in China, and well summarizes essential knowledge which can be used within a range of medicines available in Korea. This book has an outstanding structure that can be even used in today's textbook on science of medicinal ingredients, as it has clear theory, system and classification. Because it handles essential learning points prior to prescription to disease, it is possible to configure new prescription and adjustment of medicinal materials. Moreover, this book can play a good role for linguistic study at the time of publication, because it describes many drugs in Hangul in many parts of the book. "Bonchojeonghwa" includes a variety of animals, plants and mineral resources in Korea, like "Bonchokangmok" which was recently listed in UNESCO. As such, it has a significance in natural history as well as pharmacy in Korean Medicine. It has various academic relationships all in biologic & abiologic aspects. It has importance in sharing future biological resources, building up international potential, setting up the standard for biologic species under IMF system, and becoming a base for resource diplomacy. We should not only see it as a book on medicinal ingredients in terms of Oriental Medicine, but also make an prudent approach to it in terms of study strengthening Korea's national competitiveness. After bibliographical reviewing on the features & characteristics of the only existing copy of "Bonchojeonghwa" housed in Kyujanggak(奎章閣) of Seoul National University, the followings are noted. First, "Bonchojeonghwa" is a specialized book on medicinal ingredients voluntarily made by private hands to distribute knowledge on drugs in the desolate situation after Imjinoeran (Japanese Invasion in 1592), without waiting for governmental help. Second, it raised accessibility and practicality by new editing. Third, it classified 990 different kinds of drugs into plant, animal, and mineral at large, and dassified more in detail into 15 'Bu' and 48 'Ryu' at 258 pages. Fourth, the publication of this book is estimated to be around 1625~1633, at the time of Injo's reign in 17th century. Fifth, it contains the existing & up-to-date knowledge at the time of publication, and it is possible to see the supply-demand situation by Hangul descriptions in 149 places in the book. By the fact that there are many linguistic evidences of 17th century, explains well when the book was published.

Research about the Influence of Color Communication on Brand Images - based on Industrial Logos (컬러커뮤니케이션이 브랜드 이미지에 미치는 영향에 대한 연구 - 기업 로고를 중심으로)

  • Rhie, Jinny
    • The Journal of the Korea Contents Association
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    • v.12 no.5
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    • pp.154-162
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    • 2012
  • We can expect an effective color marketing to build up a positive industrial image as it is easy for consumer to approach due to the ability of colors to affect human consciousness and sub-consciousness more than any other factor. The purpose of this research is to draw attention to the importance of color communication and to find strategies to elevate the brand image by surveying the degree of influence color communication has when forming a brand image. In order to conduct effective research, we executed theoretical and collaborative analysis through research materials and documents. If you take a look at the outcome of this research, brands that brings credibility and likability to its customers are not brands that uses color communication, but brands that utilize marketing strategies that build up credibility for quite some time. Also, preference over colors are distinctive. It turned out to be that the color of a brand logo that one likes has very little to do with one's favorite color. When people choose a brand, they are choosing the brand not because of the color of the brand logo, but its credibility and likability that the brand offers. It proves that the color of the brand logo has nothing to do with the colors that people prefer. The relationship between the color that consumers prefer and the image and emotional color that forms brand image is negligible. However, since research shows that there was a relationship between the color you prefer and the emotional color that forms brand images, it seems to be important to figure out what color customers prefer rather than the color that shows customers' self image. Unlike existing color communication research, through this research, we would like to know how to utilize the color communication strategically in the forming of brand images and take a look at the relationship between customers' preferences and the image of each brand logo's emotional color.

Commonest Cancers in Pakistan - Findings and Histopathological Perspective from a Premier Surgical Pathology Center in Pakistan

  • Ahmad, Zubair;Idrees, Romana;Fatima, Saira;Uddin, Nasir;Ahmed, Arsalan;Minhas, Khurram;Memon, Aisha;Fatima, Syeda Samia;Arif, Muhammad;Hasan, Sheema;Ahmed, Rashida;Pervez, Shahid;Kayani, Naila
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.1061-1075
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    • 2016
  • Context: There are no recent authoritative data about incidence and prevalence of various types of cancers in Pakistan. Aim: To determine the frequency of malignant tumors seen in our practice and provide a foundation for building a comprehensive cancer care strategy. Materials and Methods: 10,000 successive cases of solid malignant tumors reported in 2014 were included. All cases had formalin fixed, paraffin embedded specimens available and diagnosis was based on histological examination of H&E stained slides plus ancillary studies at the Section of Histopathology, Department of Pathology and Laboratory Medicine, Aga Khan University Hospital, Karachi. The latest WHO classifications were used along with the latest CAP protocols for reporting and the most updated TNM staging. Results: There were 9,492 (94.9%) primary tumors while 508 (5.1%) were metastatic. Some 5,153 (51.5%) were diagnosed in females and 4,847 (48.5%) in males. The commonest malignant tumors in females were breast (32%), esophagus (7%), lymphomas (6.8%), oral cavity (6.7%) and ovary (4.8%), while in males they were oral cavity (13.9%), lymphomas (12.8%), colorectum (7.9%), stomach (6.9%) and esophagus (6.6%). Malignant tumors were most common in the 5th, 6th and 7th decades. About 8% were seen under 20 years of age. Conclusions: Oral cavity and gastrointestinal cancers continue to be extremely common in both genders. Breast and esophageal cancers are prevalent in females. Lung and prostate cancer are less common than in the west. Ovarian cancer was very common but cervix cancer was less so.

A Study on Changes in Indoor Air Pollution by Educational Activities -Centering on Newly-Established Elementary Schools- (교육활동에 따른 실내오염도 변화에 관한 연구 -신설 초등학교를 중심으로-)

  • Jeon, Seok-Jin
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.6 no.2
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    • pp.66-90
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    • 2007
  • The purpose of this study is to measure and analyze primary causes of indoor air pollution, including carbon dioxide, minute dust, and total volatile organic compounds, for each room before the beginning of a class through the time of discharge after the end of the class in general classrooms, computer rooms, and science rooms of three newly-established schools that opened in 2006, examine properties of indoor air environment in each room by educational activities at school, and determine effective management schemes; the results of this study can be summarized as follows: 1) As for implications for each item found in the mean for each place, since minute dust (PM10) was more likely to occur in time slots full of students' activities, such as a traveling class and a recess, than in the middle of a class and could be expected fully, it is necessary to make a scheme for cleaning in order to reduce minute dust within a room, for example, by usually using a vacuum cleaner indoors. 2) While carbon dioxide was expected to vary with the differences in the amount of breath between higher-graders and lower-graders in a general classroom but showed insignificant difference by grades, showing differences in pollution by four times at a maximum according to the opening of a window as expected, it is necessary to implement artificial or natural ventilation and take a positive measure, for example, by presenting a concrete ventilation scheme, in order to improve indoor air pollution at a room practice. 3) Total volatile organic compounds were found to exceed the standard by more than twice in general classrooms, science rooms, and computer rooms of the schools because of building materials, furnitures including desks and chairs, panels and boards for environment beautification, and items which could be detected even from students' clothes; while a field directly-reading tool was used, obtaining high reliability for the results, it is necessary to apply an analytical method based on process test separately for actual correct measurement if a significantly great amount of total volatile organic compounds appear as compared with other schools due to measuring expenses and consecutive measurements. 4) Since formaldehyde (HCHO) was generally found to exceed the standard in general classrooms, science rooms, and computer rooms, it is necessary to establish and operate a ventilator during a class in a computer room which requires airtightness and a science room in which an organic compound should be used for a class.

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A Study of the correlation between breeding density and the azimuth of cattle sheds affected calf diarrhea disease (송아지 설사에 영향을 미치는 사육밀도 및 축사 방위와의 상관관계에 관한 연구)

  • Lee, Yun-Lyul;Lee, Hak-Rim;Ahn, Jae-Bum;Song, Ji-Ye;Jang, Jae-Jin;Lee, Min-Jae
    • Korean Journal of Veterinary Service
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    • v.30 no.1
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    • pp.133-144
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    • 2007
  • This study was conducted to determine the effective environmental control measures in preventing calf diarrheal disease in farms. It was found that the high numbers of calves in a cow house was directly related with the high incidence rate of diarrheal diseases. When the number of calves was increased in a cow house, it was difficult to reduce the diarrheal diseases of calves. It was revealed that the incidence rates of calf diarrheal disease were dramatically reduced when the delivery house which faced south. The periodical changes of bedding materials seemed beneficial good to control the possible resident infectious agents, including pathogenic viruses and bacteria. The control of the delivery time was important for reduction of calf diarrhea. It was revealed that September and October were the best time as the delivery period. In order to use old cow house as a delivery house, it should be sterilized by the disinfectant and the flame. When the diarrheal feces were removed as soon as possible, the transmission of diarrheal diseases among calves In the same house was reduced. When the diarrheal feces were not disposed, the incidence rate of diarrhea reached up to 50%. When the morbid calves were not quarantined, the incidence rate of diarrhea was 100%. In contrast, when the diseased calves were quarantined from other calves, the incidence rate of diarrhea was reduced, remarkably. The mean recovery time from the diarrhea of the treated calves in the southern cow house was much faster than that in the north cow house. The treatment of calves in a clean and well-ventilated cow house with dry bedding was more effective than that in a cold, wet, and dark house. It could be postulated that the most important environmental factor in the reduction of diarrheal diseases of calves is the blocking of the entry of the infectious agents. The complete sanitation and control of the delivery house in the using farm is more important than building a new cow house, for prevention of calf diarrheal diseases.

A Study on Manufactural Condition of Vegetation Mat for Greening Impermeable Surfaces Using Wood Waste (폐목질 자원을 이용한 인공지반 녹화용 식생기반재의 제조조건에 관한 연구)

  • Kim, Dae-Young;Kim, Mi-Mi
    • Journal of the Korean Wood Science and Technology
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    • v.38 no.3
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    • pp.165-169
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    • 2010
  • The cityward tendency of the population caused the building crowd and the skyscrapers, and destroyed the cityscape and ecosystem of the city. For this reason, many researchers studied to make more green spaces in the city. The roof greening is one of the methods to get the green spaces in the city. There are some problems in this method such as the safety load, growth of the plants on the artificial foundation, and so on. In this study, we evaluated the waste woodchips and the waste papers as a new materials for the artificial foundation. The new artificial foundation was made of the waste woodchips and the waste papers with the different ratio of mixture (woodchips, paper slurry, and fertilizer). The artificial foundation was applied to the planting of three different plants (creeping bentgrass, barley, and wheat). It was found that the growth of the plants with 1% of fertilizer was higher than other conditions. The best making condition of foundation was 40% pulp and 60% woodchips in the germination of all plants.