• Journal of Climate Change Research
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• v.6 no.2
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• pp.121-131
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• 2015

As the temperature has changed by climate change, changes in its own characteristic values of the chemical substance or the movement and distribution of chemicals take place in accordance with the changes of hydrological and meteorological phenomena. Depending on the impact of climate change on the chemical behavior, it is necessary to understand and predict quantitative changes in the dynamics of the environment of pollutants due to climate change in order to predict in advance the occurrence of environmental disasters, and minimize the impact on the life and the environment after the incident. In this study, we have analysed and compared chemical fate models validated by previous studies in terms of model configuration, application size and input/output factors. The potential models applicable to municipal and industrial areas were selected on the basis of characteristic of each model, availability of input parameters and consideration for climate change, identified the problems, and then presented an approach to improve applicability.

• Conservation Science in Museum
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• v.6
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• pp.73-83
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• 2005

To understand the influence of wet cleaning performed in the course of preserving paper items, the change of matter properties by before and after wet cleaning was observed. Specifically, structural and optical qualities and strength were measured. The result showed that wet cleaning caused a substance change in the paper items and particularly weakened the structure material of pigments, Chinese ink, dyes, etc.

• The Korean Journal of Physiology
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• v.24 no.1
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• pp.39-49
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• 1990

It has been reported that bombesin induces contraction of the smooth muscle of the gastrointestinal tract. Thus, the present investigation was undertaken to see an influence of bombesin on electrical activity of the gastric smooth muscle, since electrical activity is associated with contractile activity in the smooth muscle of the stomach. Smooth muscle strips $(5\;{\times}\;1.5\;cm)$ that included the corpus and antrum were prepared from the ventral and dorsal portion of the feline stomach along the greater curvature. Circular muscle strips $(1\;{\times}\;0.3\;cm)$ of the corpus were also obtained. Electrical activity of the corpus and antrum of the muscle strip was monophasically recorded by using Ag-AgCl capillary electrodes placed on the circular muscle layer. Contractile activity of the circular muscle strip was also recorded. The recordings were performed in Krebs-Ringer solution that was continuously aerated with $O_{2}$ containing 5% $Co_{2}$, and kept at $36^{\circ}C$. Dose-related responses of electrical activity and contractility to bombesin was studied after frequency of slow waves and contraction of each strip reached to a steady state. An action of $D-leu^{13}-{\psi}\;(CH_{2}NH)-D-leu^{14}-bombesin,\;D-pro^{2}-D-trp^{7,9}-substance\;P$, tetrodotoxin, hexamethonium, atropine, phentolamine or propranolol on the effect of bombesin was also observed. 1) Bombesin increased frequency of slow waves and contractions dose-dependently at concentrations from $10^{-9}\;M\;to\;3\;{\times}\;10^{-8}\;M$. 2) The bombesin analogue at a concentration of $3\;{\times}\;10^{-7}\;M$ antagonized the effect of bombesin on frequency of slow waves. 3) The effect of bombesin on frequency of slow waves was inhibited by tetrodotoxin $(10^{-6}\;M)$ and hexamethonium $(10^{-3}\;M)$ but unaffected by atropine $(10^{-6}\;M)$, phentolamine $(10^{-5}\;M)$ and propranolol $(10^{-5}\;M)$. 4) The effect of bombesin on frequency of slow waves was blocked by the substance P analogue at a concentration of $10^{-5}\;M$. 5) Substance P at a concentration of $10^{-5}\;M$ failed to change frequency of slow waves. It is concluded from the above results that bombesin increases the frequency of slow waves as well as contractions of the smooth muscle strip from the feline stomach, and the effect of bombesin might be mediated by non-cholinergic or non-adrenergic mechanism at neuromuscular junction. However, enteric nerves that have substance P as a neurotransmitter do not appear to participate in the action of bombesin on frequency of slow waves.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.285-288
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• 2002

옥타데칸[$CH_3$[C $H_2$]$_{l6}$$CH_3$]은 상전이 물질(phase change material)이며, 상전이 물질은 상변화를 통해 주변의 온도가 상승하면 녹으면서 열을 흡수하고, 주변의 온도가 낮아지면 결정화(crystallization)하면서 열을 방출하는 축열ㆍ방열성을 반복적으로 나타내는 에너지 물질(enthalpic substance)이다[1, 2]. 옥타데칸은 메탄계열 탄화수소로서 파라핀류(paraffins)에 해당된다. (중략)략)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.305.2-306
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• 2002

In recent studies on cefodizime, it may potentially have the capability of stimulating chemotactic activity of neutrophils and monocytes as well as the strong immuno-modulator. In turn, infection can result in a drastic change of mediators. which lead to initiate an immune response in an indirect way. With this backgrounds, we have studied to see if cefodizime can be a potential substance to induce an immunological function in dendritic cells and peritoneal macrophages. (omitted)

• Journal of environmental and Sanitary engineering
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• v.14 no.4
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• pp.41-49
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• 1999

The water treatment by was performed to remove VOC and organic substances in the multi-stage ozone contactor. Ozone is mainly utilized to change the chemical structures of organic substance, of which finally has the purpose to degrad them. The removal efficiency of VOC has 20~60% at the ozone concentration of 3 ppm, in case of trichloroethylene, its efficiency is reduced by 85% at the ozone contact time of 8 min. Design factors such as the number of stage, ozone concentration, zone contact time are determined for optimal treatment in the multi-stage contactor.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 1994.06a
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• pp.29-39
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• 1994

A review on sweetener has been conducted. Enzymes are utilized preferentially to break-down or synthesize stevioside, MGGR and oligo-saccharides. these result in change or modification of the functions of sweetener. Originally, the sweetener was used to obtain energy, add sweet taste and for rheological properties. Recently, the physiological functions of the sweetener have been studied considerably. As the oligo-sacchride is found to function as substance of physiological activities, more researh will be carried out using enzyme to discover new functions of sweetener.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.23 no.2
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• pp.109-124
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• 2010

Objectives : The aim of this study is to investigate the antiallergic effects of YTT on allergic rhinitis by regulation of peroxisome proliferator-activated receptor gamma (PPAR-$\gamma$). Methods : The thirty rats were divided into three groups : normal group, control (allergic rhinitis elicited) group, sample (Yeotaectonggi-tang treated after allergic rhinitis elicitation) group. To induce allergic rhinitis in control group and sample group, rats were sensitized intraperitoneally with 0.1% ovalbumin(OVA) solution 3 times at intervals of 1 week. Then intranasal sensitization was performed by diffusing 0.1% ovalbumin(OVA) solution 3 times at intervals of 2 days. After that time rats in sample group were oral administration treated by YTT for 7days. The change of the amounts of eosinophil, substance P, MIP-2, PPAR-$\gamma$, IL-4, iNOS were observed in each group. we used the statistical method of ANOVA test(p<0.05). Results : The number of eosinophil in sample group noticeably decreased than control group. And the decrease of substance P and MIP-2 positive reaction were observed in mucosa. YTT inhibited IL-4 and iNOS production, mucus secretion, activation of mast cells and fibrosis remodeling by regulation of PPAR-$\gamma$ activation. Conclusion : According to the above results, it is considered that YTT mitigated mucosa damage on the mice model with allergic rhinitis by regulation of PPAR-$\gamma$.

• Journal of the Korean Chemical Society
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• v.51 no.1
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• pp.65-72
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• 2007

The purpose of this study was to examine the 7th national science curriculum (chemistry domain) regarding the meanings of ‘mulgil' (Korean), the particulate nature of matter, and the state of matter. It was found that the term of ‘mulgil' was being used vaguely as representing material, matter, or substance without clear definition. This was problematic by reason that it could hinder students from having the concept of substance. Regarding the particulate nature of matter, molecule was introduced as a basic unit of matter at grade 7, prior to atom and ion, which were introduced at grade 9 and 10, respectively. It is necessary to reconsider the sequence of each particle concept to provide students with more consistent and comprehensive understanding of structure of matter. In the case of change of state, key concepts such as conservation of matter or reversibility were omitted in the curriculum document, and explanations based on various aspects of particles were somewhat insufficient. The concept of matter is fundamental to chemistry, and we must recognize it as a concept that needs to be taught clearly. Implications for curriculum revision were discussed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.881-883
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• 2005

In case is below length 100nm of gate, various kinds problem can be happened with by threshold voltage change of device, occurrence of leakage current by tunneling because thickness of oxide by 1.5nm low scaling is done and doping concentration is increased. SiO$_2$ dielectric substance can not be used for gate insulator because is expected that tunneling current become 1A/cm$^2$ in 1.5nm thickness low. In this paper, devised double gate MOSFET(DGMOSFET) to decrease effect of leakage current by this tunneling. Therefore, could decrease effect of these leakage current in thickness 1nm low of SiO$_2$ dielectric substance. But, very big gate insulator of permittivity should be developed for develop device of nano scale.