• Title/Summary/Keyword: the nineties

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Inorganic phosphors for LED applications

  • Winkler, Holger;Barnekow, Peter;Benker, Andreas;Petry, Ralf;Tews, Stefan;Vosgroene, Tim
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.56-59
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    • 2009
  • In the nineties the invention of the InGaN blue LED has innovated illumination technology. Currently LCD backlighting and more and more general lighting applications are based on white LEDs comprising of inorganic phosphors and blue emitting InGaN chip. Well established phosphor materials are ortho silicates and garnets like yellow emitting YAG:Ce. In our paper we demonstrate that garnet materials also allow for green light emission for both, general lighting and backlighting LED applications.

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¿México: revolución truncada o democracia intempestiva? El problema: equidad-calidad en la educación básica

  • Mendez-Ramirez, Oswaldo
    • Iberoamérica
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    • v.12 no.2
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    • pp.383-428
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    • 2010
  • To make a critical revision on the inherited social problems throughout the time in Mexico, not always turns out to be easy task, especially when the subject is lent to approach it from diverse perspective, one of them, the educative one. To analyze the low quality of the educative supply is complex subject. One of the maximum profits of institutional revolutionary Mexico was the creation of the Public Education Ministry in 1921. In the post-revolutionary and modern period, the seventies were characterized to be applied to the growth the infrastructure and the fortification of the educative system following the policy of "modernization and development". From the eighties, to lift the quality of the education was considered like one of the specific rules in the strategy of the call "educative revolution". In the nineties, through political programs and agreements, structural changes within the educative system were carried out with the intention to lift the quality of the services. In synthesis, the perspective in the educative policy of Mexico during the last thirty years of century xx, or post-revolutionary period, can be understood, from at least five specific conditions: educative profits in cover, modifications in the educational programs and contents, profits in the political agreements between the agents who take part within the educative system, changes and modifications to the laws applicable to the education, and; the search of the fairness through the compensatory programs. This paper tries to give answer to questions such as: The educative system reflects the ideals of the revolution? The present educative system is the product of a truncated revolution or the fruit of an untimely democracy?

A Study on the Change of Fashion Model's Image with the Changes of the Times (시대에 따른 패션모델의 이미지 변화에 관한 연구)

  • Kim, Myung-Hee;Kim, Sun-Hwa
    • The Research Journal of the Costume Culture
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    • v.16 no.4
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    • pp.735-747
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    • 2008
  • This study was about the fashion model's images during the periods of time. Also, this was to know the model's role and fields they had worked in and to investigate the specializing courses to get advice from their diversities, specialties and activities. The method of the study was used the qualitative analysis from the relative books, theses from university graduates, the related society newsletters, fashion magazines that were printed periodical/non-periodical, and others. As a result, the glamourous image was the most famous in the twenties and thirties, and the elegant image mainly in the forties and fifths. The images were more diverse in the nineties through the girlish images of the sixties, and the sexy image with good health of the seventies and eighties. Baby faces became the ideal of models in the new century. The images of the models become popular and disappear rapidly due to the change of major trend with the change of the society's environment. Under the situation, they must take good care of their images and self-control themselves to keep a positive view of fashion models to the public, and they must have ambition as a fashion icon and make their own exclusive fields in various parts.

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A Study on the Romantic Image in Modern Fashion (현대패션의 로맨틱 이미지에 관한 연구)

  • Kim Young-Hyun;Yang Chieu-Kyung
    • Journal of the Korean Society of Costume
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    • v.55 no.1 s.91
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    • pp.1-12
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    • 2005
  • The modern society which is going through the big turbulence of civilization experiences the lost of humanity and the phenomenon that the standard of our thoughts, like those for good and evil, truth and false is not clear anymore as the technology is being improved. This makes us miss the past when everything is simple and the standards are very clear and being attracted by the metaphorical culture symbolizing something from the past, like memories of youth, fantasies, fairy tales or myths and we are now having a great interest in the joy of life and the affluent life. Influenced by this kind of tendency in modern society, the minimalism, which had the great influence in the nineties, went out of fashion and at last the romantic susceptibility seems to be the trend forming the major mood of the late 20th century - the early 21st century. This study focus is: (1) the theoretical aspects of romantic images such as the concept, the historical tendency and the character are considered. (2) the variety and multiplicity of the romantic images is discussed after the romantic image is classified into four types of retro character, natural character, ethnic character, erotic character according to major trends in our modern. The purpose of this study is to understand the romantic images in modern fashion, by analyzing the fashion trends together with the various features of romantic images.

Electrolytes - Quality at Point of Use

  • Heider U.;Jungnitz M.;Oesten R.
    • 한국전기화학회:학술대회논문집
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    • 1998.12a
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    • pp.153-166
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    • 1998
  • Lithium ion Batteries commercially available since the early nineties in Japan are going to be more and more important for portable electronic devices and even EV applications. Today several companies around the world are working hard to join to market for Lithium secondary batteries. Based on the growing interest for commercial use of batteries also the materials have to be reviewed in order to meet large scale production needs. The requirements especially for electrolytes for lithium batteries are extremely high. The solvents and the lithium salts should be of highest purity. So the supply of these chemicals including packaging, transportation and storage but also the handling in production are critical items in this field. Frolic impurities are very critical for LiPF6 based electrolytes. The influence of water is tremendous. But also the other protic impurities like alcoholes are playing an Important role for the electrolyte quality. The reaction of these species with LiPF6 leads to formation of HF which further reacts with cathode materials (spinel) and anode. To understand the role of the protic impurities more clearly the electrolyte was doped with such compounds and was analyzed for protic impurities and HF. These results which directly show the relation between impurities and quality will be presented and discussed. In addition several investigations on different packaging materials as well as methods to analyze and handle the sensititive material will be addressed. These questions which are only partly discussed in literature so far and never been investigated systematically cover some of the key parameters for understanding of the battery chemicals. This investigation and understanding however is of major importance for scientist and engineers in the field of Lithium ion and Lithium polymer batteries.

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Independent Component Analysis(ICA) of Sleep Waves (수면파형의 독립성분분석)

  • Lee, Il-Keun
    • Sleep Medicine and Psychophysiology
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    • v.8 no.1
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    • pp.67-71
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    • 2001
  • Independent Component Analysis (ICA) is a blind source separation method using unsupervised learning and mutual information theory created in the late eighties and developed in the nineties. It has already succeeded in separating eye movement artifacts from human scalp EEG recording. Several characteristic sleep waves such as sleep spindle, K-complex, and positive occipital sharp transient of sleep (POSTS) can be recorded during sleep EEG recording. They are used as stage determining factors of sleep staging and might be reflections of unknown neural sources during sleep. We applied the ICA method to sleep EEG for sleep waves separation. Eighteen channel scalp longitudinal bipolar montage was used for the EEG recording. With the sampling rate of 256Hz, digital EEG data were converted into 18 by n matrix which was used as a original data matrix X. Independent source matrix U (18 by n) was obtained by independent component analysis method ($U=W{\timex}X$, where W is an 18 by 18 matrix obtained by ICA procedures). ICA was applied to the original EEG containing sleep spindle, K-complex, and POSTS. Among the 18 independent components, those containing characteristic shape of sleep waves could be identified. Each independent component was reconstructed into original montage by the product of inverse matrix of W (inv(W)) and U. The reconstructed EEG might be a separation of sleep waves without other components of original EEG matrix X. This result (might) demonstrates that characteristic sleep waves may be separated from original EEG of unknown mixed neural origins by the Independent Component Analysis (ICA) method.

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Effect of Surface Ozone on Vegetation in Korea - Preliminary Study on Early Foliage of Robinia pseudo-acacia - (한국의 지면 오존이 식생에 미치는 영향에 관한 연구 - 아까시나무 조기낙엽 현상과 관련성 검토 예비 연구 -)

  • Cho, Seog-Yeon
    • Journal of Korean Society for Atmospheric Environment
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    • v.23 no.1
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    • pp.29-38
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    • 2007
  • Recently, the tropospheric ozone has gained a global attention for its adverse effect on vegetation as well as its contribution to the global warming. Although a number of studies have been carried out for the urban ozone, the effect of ozone on vegetation is still largely unknown in Korea. The present work aimed at performing the first evaluation of forest damage by ozone using the national air monitoring data from the year 2000 to the year 2005. Moreover, it also explored the relevance of adverse effect of ozone to the recent events on leaf chlorosis of black locust, Robinia pseudo-acacia, leading to early foliage widely observed in Korea since 2001. In the nineties, forest damages caused by ozone such as leaf chlorosis occurred in Europe and North America and led to invoke comprehensive field and laboratory studies. As a result, AOT40, implying the accumulated dose over a threshold 40 ppb, was developed to assess the forest damage by ozone. 19 air monitoring stations were selected across Korea to calculate AOT40 from the year 2000 to the year 2005. The calculated AOT40 generally increased during April and May and reached the maximum after May. The increase of AOT40 diminished substantially from the mid-June as the rainy season started. The calculated AOT40 in the nine rural sites from the year 2002 to th ε year 2005 ranged from 6.8 to 29.4 ppm-hr. And all the AOT40 at th ε year 2005 exceeded the critical value of 10 ppm-hr for forest damage. Morevoer the calculated AOT40 of Korea appeared higher than the AOT40 of Europe in the year 2004/2005 and comparable to the AOT40 of China in the year 2000. Despite the high levels of the calculated AOT40 since the year 2001 and the consistency of time of seasons between high AOT40 values and occurrence of chlorosis of black locust, further studies are required to conclude that the chlorosis of black locust occurred from the year 2001 to the year 2005 were resulted from a damage by ozone.

Changes of Contents and Formats of Science Texbooks of North Koean Secondary School in the Eighties and Nineties -Mainly in the Field of Chemistry- (80년대와 90년대 북한 고등중학교 과학 교과서의 체제와 내용 변화-화학 분야를 중심으로-)

  • Noh, Suk Goo
    • Journal of the Korean Chemical Society
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    • v.44 no.4
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    • pp.363-375
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    • 2000
  • In this study, the changes of contents and formats of science textbooks of North Korean sec-oery much and the quality of papers in the textbooks became worse. The changes of ratios of contents were as follows. While the ratio of 'Chemical Change' was increased especially in the contents of 'Acids and Bases' and 'Oxidation and Reduction', the ratios of'EIements and Compounds' and 'Structure of theMaterials' were decreased. The ratio or 'Science-Technology-Society' which hasbeen stressed very much recently in the science education was low in the eighties, and the ratio is even lower in the nincties. 0n the basis of these facts,it can be concluded that the world-wide recent trends in science education hardly affected North Korean science education.

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Profile of Lung Cancer in Kuwait

  • El-Basmy, Amani;Al-Mohannadi, Shihab;Al-Awadi, Ahmed
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.6181-6184
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    • 2013
  • Background: Lung cancer is the most frequent cancer in males and the fourth most frequent site in females, worldwide. This study is the first to explore the profile of lung cancer in Kuwait. Materials and Methods: Cases of primary lung cancer (Kuwaiti) in Kuwait cancer Registry (KCR) were grouped in 4 periods (10 years each) from 1970-2009. Epidemiological measures; age standardized incidence rate (ASIR) with 95% confidence intervals (CI), Standardized rate ratio (SRR) and Cumulative risk and Forecasting to year 2020-2029 used for analysis. Results: Between years, 2000-2009 lung cancer ranked the 4th and the 9th most frequent cancer in males and females respectively. M:F ratio 1:3. Mean age at diagnosis (95%CI) was 65.2 (63.9-66.4) years. The estimated risk of developing lung cancer before the age of 75 years in males is 1.8% (1/56), and 0.6 (1/167) in females. The ASIR for male cases was 11.7, 17.1, 17.0, 14.0 cases/100,000 population in the seventies, eighties, nineties and in 2000-2009 respectively. Female ASIR was 2.3, 8.4, 5.1, 4.4 cases/100,000 population in the same duration. Lung cancer is the leading cause cancer death in males 168 (14.2%) and the fifth cause of death due to cancer in females accounting for 6.1% of all cancer deaths. The ASMR (95%CI) was 8.1 (6.6-10.0) deaths/100,000 population and 2.8 (1.3-4.3) deaths/100,000 population in males and females respectively. The estimated Mortality to incidence Ratio was 0.6. Conclusions: The incidence of lung cancer between years 2000-2009 is not different from that reported in the seventies. KCR is expecting the number of lung cancer cases to increase.

An Analysis on the Re-visitation Choice of Rural Leisure - Focused on Buraemi, Daraengi, Byucgari region - (농촌여가 시장의 재방문 선택요인 분석 -부래미, 다랭이, 볏가리지역을 대상으로-)

  • Yun, Hee-Jeong;Im, Seung-Bin
    • Journal of Korean Society of Rural Planning
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    • v.14 no.2
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    • pp.33-42
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    • 2008
  • Recently, rural leisure by urban dwellers has been recognized as a catalyst for regional development or restoration. The federal government implemented several regional planning policies attempting to address this phenomenon in the late nineties. However, most of these policies focused on supply-centered planning, which caused a diverse set of problems relating to the sustainability and economic validity of the planning. Instead, this study focuses on the re-visitation one of the demand variables, with the intention of analyzing the character of rural leisure demand and its re-visitation choice attributes. For these reasons, this study investigates the character of current rural leisure demand, and develops functional equations about urban people who visit rural areas, using logit model. The results of this study can be summarized as follow: Urban people are visiting rural areas from nearby cities or metropolitan areas that are within 3 hours driving distance, and over 80% of rural visitors are one-day visitors. Therefore, most of their visitation activities should be understood as rural leisure, including rural tourism. In addition, the likelihood of the rural tourist to make a return visit is influenced by their transportation means, product purchasing, staying period and travel time. The results of such rural leisure demand can provide information for regional planning strategies, such as selection of target market, type of market segments, improvement of recognition level, activity program price, facility and space planning, produce sale and connection with tour site.