• Title/Summary/Keyword: Work-function

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Effect of Euonymus alatus and Ulmus clavidiana var japonica on the immune system (화살나무 및 느릅나무 추출물이 면역계세포의 활성에 미치는 영향)

  • Kim, Jong-myeon;Choi, Min-soon;Cho, Jeong-gon;Jung, Young-mee;Park, Tae-wook
    • Korean Journal of Veterinary Research
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    • v.34 no.2
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    • pp.307-313
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    • 1994
  • We have previously shown that crude water extract of Euonymus alatus (EA) had strong prophylactic effect against chemically induced-and tumor cell implanted-cancer, and that the mechanisms responsible for its antitumor effects were due to nonspecific enhancement of the NK cell activities and the cell mediated immunity. However, it was unknown that any components of crude extract did work so, since it consisted of several components. In this paper, we fractionated the crude watar EA-extract into several fraction such as hexane-, ethylether-, ethyl acetate-, n-butanol- and water soluble-fraction, and screened the immune regulating activities of each fraction by the evaluation of lymphokine production and activated lymphocyte proliferation. As a result of the component fraction of EA-extract, it was found that n-butanol fraction was a potent immunostimulator, and the remained water soluble fraction also contained some stimulator, But, other fraction did not showed any remarkable effect. It is therefore suggested that EA-glycosides in n-butanol fraction may be new one of the potent biological response modifiers. The present study was also undertaken in an efforts to investigate the effects of elm-bark(EB, Ulmus clavidiana var japonica), which has been used for curing ulcer and inflammation as a folk medicine without any kind of experimental evidence to support this, on the cellular- and humoral-immune responses, lymphocyte function and NK cell activities in mice. Regardless of time and duration of EB-treatment, Arthus reaction and antibody response to SRBC were not modified by EB, but delayed hypersensitivity to SRBC was significantly enhanced only when EB was treated prior to SRBC-sensitization. EB slightly inhibited the proliferation responses of splenocytes to PHA-stimulation, but it significantly augmented the responses of these cells to S aureus Cowan 1 and Con A-activation, and these effects were manifested only when EB was added at culture initiation. EB did not influence Ig secretion of spleen cells but it significantly augmented the Con A-induced 1L 2 and MIF production of splenocytes. NK cell activities of splenocytes were markedly riled when effector cells were pretreated with EB and this augmentation was dine to the increase of binding affinity of effector cells to target cells and the target cell lytic activities of effector cells. These results led to the conclusion that EB triggers increase of cellular immune responses, such as delayed hypersensitivitiy, lymphokine production and NK cell activities. Also these results suggested that EB contains potent immune stimulants, which may provide the rational basis for their therapeutic use as one of the new biological response modifiers.

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Structure/Property of Adhesives and Adhesion Performance (접착제의 구조물성과 접착특성)

  • Hiroshi Mizumachi
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.29 no.1
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    • pp.73-83
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    • 1997
  • Most of the materials used in various industrial fields and also in our daily life are multi-component materials or composite materials, and it is well known that there are many cases where adhesion between the constituents within the bonded systems plays an important role. There are various types of performance evaluation tests for the bonded materials, among which tests for evaluating the bond performance under various conditions may be regarded as the most interesting ones for those engaged in work related to adhesion. I have studied on the mechanism of adhesion form the rheological standpoint with my colleagues, including some students from Korea, and I am very happy to be able to have a talk on some of our research works. In Japan, the so-called "adhesives" are usually classified into two categories;adhesives and pressure sensitive adhesives (PSA). Adhesives are the materials which solidify after bonding and are after used as the structural adhesives because the adhesive strength is comparatively strong. On the other hand, the pressure sensitive adhesives never solidify and are used as PSA tapes, labels or decals. About the adhesives, we have examined the dependence of adhesive strength(shear, tensile, peel) upon both temperature and rate of deformation, and found out some empirical rules which are applicable to most of the adhesive systems. We have also developed a simplified theory of adhesion, which is deseribed in terms of mechanical equivalent mode1 and a few failure criteria. Although some of the common rules can be accounted for according to this theory, it must be pointed out that a fracture mechanical approach ms inevitable especially in the region where the meehanical relaxation time of the adhesive is extremely large [W. W. Lim and H. Mizumachi]. About the pressure sensitive adhesives, we have studied on the PSA performance (peel, tack, holding power) as a function of both the viscoelastic properties and surface chemical properties of the materials, and found out some rules, and again we have developed a theory which deseribes the mechanism. And in addition, we have studied on the miscibility between linear polymers and oligomers, because PSA is generally manufactured by blending gums and tackifier resins. Many phase diagrams have been found and some of them have been analyzed on thermodynamic basis, and it became evident that the miscibility is a very important factor in PSA [H. J. Kin and H. Mizumachi]. In this presentation, I want to emphasize the fact that the adhesion performance is closely related to the structure/property of the adhesives.adhesives.

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A Study on the Evaluation Method of Close-to-Nature Stream Improvement Works (자연 친화적인 하천 정비사업의 평가방법에 관한 연구)

  • Kim, Seok-Gyu;Kim, Chul
    • Journal of Korea Water Resources Association
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    • v.40 no.7
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    • pp.503-510
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    • 2007
  • In the area of such a nature-friendly stream improvement, it is not established yet which engineering method is suitable for stream environment, due to lack of technology. Therefore, although nature-friendly stream improvement was done with expensive engineering method, the effect has not been fully confirmed, which results from the absence of overall valuation tool of stream improvement. In this regard, it is necessary to develop and apply comprehensive and diverse valuation methods covering stream functions to the analysis of stream improvement. In this study, we collected data from years' of monitoring on the Gyeongcheon river, which is located in Sunchang-eup, Jeollabuk-do and recently underwent an nature-friendly stream improvement work. Based on the data, we developed a series of valuation methods such as stream naturalness evaluation, life cycle evaluation, amenity evaluation, and economic benefit analysis to consider the environmental function of stream from a comprehensive perspective. Stream naturalness evaluation is a quantitative analysis of how natural a stream is, and includes additional valuation items such as ecosystem and water quality for the purpose of overall valuation, unlike existing research focusing on physical elements and structural characteristics of a stream. We developed a method of stream valuation with life cycle assessment to river reorganization project. Amenity evaluation method was developed as a means to analyze residents' satisfaction with stream improvement through questionnaires. Economic benefit analysis was developed as a means to determine the attributes of environmental water supply, ecosystem, river maintenance, and water quality and predict economic benefits using contingent valuation method (CVM) and multi-attribute utility analysis (MAUA) method in order to analyze economic benefits brought in by stream improvement. It is considered that the four methods developed in this study make possible to conduct an overall and quantitative analysis of stream improvement.

Problems and Improvement Measures for the transformation of World Geodetic System (지적공부의 세계측지계 변환에 따른 문제점 및 개선방안)

  • Kim, Geun-Bae;Jeong, Gu-Ha;Jeon, Jeong-Bae
    • Journal of Cadastre & Land InformatiX
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    • v.49 no.2
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    • pp.123-134
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    • 2019
  • The introduction of the world geodetic reference system in cadastral sector can apply the international standardization of cadastral survey and can be the basis for the creation of new industries by merging with other industries based on spatial information. With the introduction of the world geodetic reference system, non-coincidence land may cause problems which are whether the cadastral record and the real estate register are not consistent, etc. This problem infringes on the protection of ownership of citizens suggested in the main purpose of 「Act On The Establishment, Management, Etc. Of Spatial Data」. We have analyzed at overlapping cases between private land and overlapping cases between national and public land and suggested institutional improvement measures to solve problems arising on the site. As a result, it will be necessary to introduce a transformation verification measure by the world geodetic reference system in order to assign a function as a cadastral records to mapping converted to the world geodetic reference system. It is also expected that the legal and institutional basis should be established for alert adjustment and positioning through verification measures. Finally, it is difficult to determine the transformation factor as the co-ordinates of common points also differ because survey results vary by work area. Therefore, it is deemed necessary to consider the requirement to use the cadastral measurement basis by the world geodetic reference system in 2021.

A Study on 3D Visualization Strategy of Cadastral Spatial Information (지적공간정보의 3차원 가시화 방안 연구)

  • Kim, Jae In;Kim, Tae Jung;Bae, Sang Keun;Jeong, Dong Hoon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.spc4_2
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    • pp.413-420
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    • 2014
  • Cadastral spatial information closely related to ownership of people is potentially very valuable information. As 3D cadastre has been actively discussed to reflect realistic living territory and legal relationship in recent years, it is highly expected to be created added value before long using that information. However, in aspect of visualization that performs an important function for decision making by facilitating intuitive thinking about spatial information, systematic solution has not been suggested to visualize the cadastral spatial information on a map with existing 3D spatial information. For that reason, in this paper, visualization method was proposed to integrate the cadastral spatial information with the existing information effectively. Requirements for 3D cadastral spatial information system were drawn based on literature review, and then specific visualization method was established by constructing user scenarios. Research results of this paper are highly expected to be applied to the integration work with the existing 3D information on a spatial information open platform.

Process Fault Probability Generation via ARIMA Time Series Modeling of Etch Tool Data

  • Arshad, Muhammad Zeeshan;Nawaz, Javeria;Park, Jin-Su;Shin, Sung-Won;Hong, Sang-Jeen
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.241-241
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    • 2012
  • Semiconductor industry has been taking the advantage of improvements in process technology in order to maintain reduced device geometries and stringent performance specifications. This results in semiconductor manufacturing processes became hundreds in sequence, it is continuously expected to be increased. This may in turn reduce the yield. With a large amount of investment at stake, this motivates tighter process control and fault diagnosis. The continuous improvement in semiconductor industry demands advancements in process control and monitoring to the same degree. Any fault in the process must be detected and classified with a high degree of precision, and it is desired to be diagnosed if possible. The detected abnormality in the system is then classified to locate the source of the variation. The performance of a fault detection system is directly reflected in the yield. Therefore a highly capable fault detection system is always desirable. In this research, time series modeling of the data from an etch equipment has been investigated for the ultimate purpose of fault diagnosis. The tool data consisted of number of different parameters each being recorded at fixed time points. As the data had been collected for a number of runs, it was not synchronized due to variable delays and offsets in data acquisition system and networks. The data was then synchronized using a variant of Dynamic Time Warping (DTW) algorithm. The AutoRegressive Integrated Moving Average (ARIMA) model was then applied on the synchronized data. The ARIMA model combines both the Autoregressive model and the Moving Average model to relate the present value of the time series to its past values. As the new values of parameters are received from the equipment, the model uses them and the previous ones to provide predictions of one step ahead for each parameter. The statistical comparison of these predictions with the actual values, gives us the each parameter's probability of fault, at each time point and (once a run gets finished) for each run. This work will be extended by applying a suitable probability generating function and combining the probabilities of different parameters using Dempster-Shafer Theory (DST). DST provides a way to combine evidence that is available from different sources and gives a joint degree of belief in a hypothesis. This will give us a combined belief of fault in the process with a high precision.

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fMRI evidence of compensatory mechanisms during a verbal working memory task in individuals with alcohol use disorders (알코올 사용 장애자의 언어 작업 기억과 관련된 뇌의 보상 기전: fMRI 연구)

  • Park, Mi-Suk;Son, Seon-Ju;Park, Ji-Eun;Eum, Yeong-Ji;Kim, Suk-Hui;Yu, In-Gyu;Son, Jin-Hun
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2009.05a
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    • pp.101-104
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    • 2009
  • This study investigated compensatory mechanisms in the brain during a verbal working memory task among people with Alcohol Use Disorders (AUD). A total of 21 college male students participated in the study: eleven AUD participants and 10 normal controls. Study participants were asked to complete the Korean version of the Wechsler Adult Intelligence Scale-III (K-WAIS-III) prior to the fMRI experiment. Verbal 0-back and 2-back tasks were used to assess brain activities of the participants' verbal working memory. Brain scanning was performed on Siemens SONATA 1.5T Scanner while participants were performing the 0-back and 2-back tasks. Within the AUD group, participants with greater dependency to alcohol (based on DSM-IV criteria) in the past 1 year showed lower mean score on the 'Similarities' of the K-WAIS-III (r=-0.63, p<0.05, N=11). The more participants experienced alcohol withdrawal symptoms in the past 1 year, the lower the score they received on the K-WAIS-III 'Picture Arrangement' (r=-0.69, p<0.05, n=11). The fMRI regression results showed that individuals who present greater degree of alcohol dependency symptoms are likely to show greater brain activation in the bilateral middle frontal gyri (BA 9) during the verbal working memory task. The degree of alcohol withdrawal symptoms were associated with increased brain activation in the left superior and middle frontal gyri (BA8), left precentral gyrus (BA 6), and left inferior parietal lobule (BA 40). The study findings showed that the degree of alcohol abuse/dependence and withdrawal symptoms were associated with decreased cognitive function and increased activations in brain regions particularly important for abstract reasoning (BA 9), central executive (BA 9), or spatial storage (BA 40) during a working memory task. Therefore, these results could support previous studies suggesting that the neural system of people with ADD may adopt a brain compensatory mechanism to maintain normal level of cognitive functions.

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Implementation of Random Controlling of Convergence Point in VR Image Content Production (VR 영상콘텐츠 제작을 위한 컨버전스 포인트 임의조절 구현)

  • Jin, Hyung Woo;Baek, Gwang Ho;Kim, Mijin
    • Smart Media Journal
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    • v.4 no.4
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    • pp.111-119
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    • 2015
  • As a variety of HMD(Head Mounted Display) has come out, the production of 3D images onto which VR(Virtual Reality) technologies are grafted has been contributed to activating the production of image contents depending on a tangible or immersing type. VR-based image contents have enlarged their applicability across the entertainment industry from animation and game to realistic images. At the same time, the solution development for producing VR image contents has also gained elasticity. However, among those production solutions which have been used until now, fixed stereo camera based photographing has a limit that the binocular disparity of a user is fixed. This does not only restrict a way of expression a producer intends to direct, but also may cause the effect of 3D or space not to be sensed enough as view condition is not considered enough in a user's side. This study is aimed at resolving with skills applying in the latter part of 3D image production the problem that convergence points may be adjusted with restriction, which tends to happen at the time of the production of VR image contents. The later stage of the 3D imaging work analyzes and applies to game engines the significance of adjusting convergence points through the visualization of binocular disparity so that it is available to implement a function that the points could be controlled at random by a user.

Physical Properties and Cleaning Ability of New Cleaning Agents Based on 2,2,2-trifluoroethanol (TFEA) (2,2,2-trifluoroethanol (TFEA)를 기초로한 세정제의 물성 및 세정성 영향 연구)

  • Cha, An Jung;Park, Ji Na;Kim, Honggon;Bae, Jae Heum
    • Applied Chemistry for Engineering
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    • v.16 no.4
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    • pp.533-541
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    • 2005
  • Non-aqueous cleaning agents were formulated with 2,2,2-trifluoroethanol (TFEA) and hydrofluoroether (HFE), and their physical properties and cleaning abilities were examined. TFEA-based aqueous cleaning agents were also formulated with nonionic surfactants, hydrotropes and builders, and their cleaning abilities were compared. Possibilities of these cleaning agents as substitutes for CFC-113 and 1,1,1-TCE were finally evaluated. In this work, fluxes, cutting oils, greases, and fluoric oils were selected as model contaminants for cleaning experiments. These contaminants have different properties of water-solubility or hydrophilicity, and fat-solubility or lypophilicity. Cleaning abilities of TFEA-based cleaning agents were analyzed and compared through the measurement of contaminant weight changes as a function of cleaning time, and their possibilities as alternative cleaning agents were evaluated. As a result, it was shown that TFEA and HFE-based non-aqueous cleaning agents have quite a good cleaning power for fluxes and fluorine soils but low one for greases. And TFEA-based agueous cleaning agents which consisted of nonionic surfactants, hydrotrope, and builders were very effective for cleaning fluxes and greases under certain formulation conditions. Thus, it was revealed that the TFEA-based cleaning agents were very effective for cleaning specific contaminants and can be used as substitutes for CFC-113 and 1,1,1-TCE in some industrial applications.

Current Status and Regulation Issues of the Functional Dairy Products in European Countries and the United States of America (기능성 유제품의 생산 현황 및 관리제도 - 미국.유럽을 중심으로 -)

  • Yoon, Sung-Sik;Song, Tae-Suk;Jeon, Sang-Rok;Park, Da-Jeong;Park, Jung-Min;Woon, Jae-Ho;Lim, Kyung-Jong;Kim, Jin-Man
    • Journal of Dairy Science and Biotechnology
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    • v.26 no.2
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    • pp.9-22
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    • 2008
  • This work has been conducted as a part to set up the regulations and the scientific evaluation systems for the functional dairy products with health claims in Korea. Toward this end, current regulations, requirements, and all kinds of provisions related to the functional dairy products overseas were taken into accounts and feasible recommendations of new initiatives on the current regulations as well. By doing so, not only protecting hopefully the innocent consumers from the false labeling statements and fake advertisements, but also eventually to revitalize the stagnated domestic dairy industries. Currently, functional daily products are simply regarded as "Dietary Supplements" in the United States, and subjected to the regulations under the Dietary Supplement Health and Education Act, established m 1994. Manufacturers and sales distributors should notify their products to the FDA, which is in charge of the dietary supplements on nutrition and labeling, in advance when they start marketing a new dietary ingredient or any foods containing it in the States. For EU countries, there exists keen interests about the functional food products between the member countries of the European Union even though the products are categorized into "Food Supplements" similar to those in the United States. Therefore, they maintain a cautious attitude in applying the health claims to the functional food products. On the other hand, under the Japanese health food system, functional foods are qualified to the functional health foods in terms of legal status as long as any traditional foods can meet the legal standards in its effectiveness, safety as well as quality, along with significant scientific evidences related to the products, thus categorized into "Foods for Specified Health Uses and "Foods with Nutrient Function Claims". Through this study, we may have some expectations and potential utilizations as follows: Legal regulations of dietary supplements especially for the dairy products will be implemented by the outcomes of this research and proposed a tentative amendment of functional ingredients for the sake of consumer protection from the false advertisements and overstatement labeling. Current regulations on the animal foods processing and advertisements will be amended and supplemented in order to revitalize the current downturn dairy sales and to harmonize the international Codex recommendations. The results obtained from this study will make the consumers a wise selection of the dairy products with health claims and be utilized for consumer education and advertisement of the functional products as well.

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