• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.8
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• pp.695-700
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• 2014

In the present study, the melting temperature depression of Sn nanoparticles manufactured using the modified evaporation method was investigated. For this purpose, a modified evaporation method with mass productivity was developed. Using the manufacturing process, Sn nanoparticles of 10 nm size was manufactured in benzyl alcohol solution to prevent oxidation. To examine the morphology and size distribution of the nanonoparticles, a transmission electron microscope was used. The melting temperature of the Sn nanoparticles was measured using a Differential scanning calorimetry (DSC) which can calculate the endothermic energy during the phase changing process and an X-ray photoelectron spectroscopy (XPS) used for observing the manufactured Sn nanoparticle compound. The melting temperature of the Sn nanoparticles was observed to be $129^{\circ}C$, which is $44^{\circ}C$ lower than that of the bulk material. Finally, the melting temperature was compared with the Gibbs Thomson and Lai's equations, which can predict the melting temperature according to the particle size. Based on the experimental results, the melting temperature of the Sn nanoparticles was found to match well with those recommended by the Lai's equation.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.4
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• pp.375-380
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• 1984

A pot experiment was conducted to learn the effect of non-compounded and compounded (with super phosphate) liquid fertilizers made of amino acid fermentation by product and the time of their application on the emergences and yield of orchard grass. Results obtained as follows; 1. The Application of the liquid fertilizers, on seeding day of the orchard grass raised soil pH and salt concentration more than the application on the days before seeding and decreased the number of sprouts of the grass which also lead to a lower yield of the grass compared with the latter. 2. Liquid compound fertilizer, however, tended to reduce the harmful effect on sprouting orchard grass compared with non-compounded liquid fetilizer, particulary in soil of on-lime applied. 3. The application of liquid and liquid compound fetilizers on somewhat acidic bare land a quite ahead of seeding or transplanting crops may not only reduce the effect of the fertilizers, provided the land is free from washing by rain or irrigation water, but also provide better conditions for sprouting and early growth of plant seedings than the use at the pre-seeding or pro-transplanting time.

• Korean Journal of Health Education and Promotion
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• v.9 no.1
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• pp.39-47
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• 1992

This study was surveyed among 1136 respondent of high school girls in seoul from Feb. 6, till Feb. 22, 1992 for the purpose of analysing the smoking of high school girls and its factor. The data was analied by X²-test and Multiple Regression and shows the following. 1. Out of 1,136 respondent, the current smokers were found to be 176, 15.5% and the former smokers were 204, 18.0%. This implies that 23.5% of high school girls seoul have experience smoking. 2. For the first smoking time in both smoking group and former smokers, it shows that the third grade of middle school lead the lists. 36.9% (65) of the smokers and 37.3(75)of former smokers experienced the first smoking at that time. 70.5%(124) of the smoking group have the intention to stop smoking and the first reason of it is health problem, 65.6%(75). 3. For the type of the school the smoking rate rages from 2.7%(7) of literary part in day time to 25.3%(97) of vocational part in evening time and the rate of smoking experience shows from 9.9%(26) literary part in day time to 25.3%(97) of vocational part in evening time. This data show that literary part in day time has the lowst rate while vocational part in eveing time the highest rate. 4. Compared with non smoker group, smoking group and former smoking group spent more money (P<0.001) and felt dissatisfied with school life and didn't have good school records. 5. Smoking group and former smokers have more boy friends than non smoking group and in most cases their boy friend have smoking habits (P<0.001) and it is the same with their gril friend (P<0.001). 6. Compared with non smoker group, smoking group and former smokers lack of their parents' interest (P<0.001). But whether it is strict or free there is little difference among the three group. 7. For smoking group and former smoking group, in most cases their parent, brother and sister tend to smoke and especially their sisters' smoking has much influence on their smoking in comparison with non-smokers. 8. Compared with non-smoker group, smoking group and former smoking group tend to think less of the harm of smoking. In regard with health problem, more smoking group and former smokers think that smoking can relieve the stress (P<0.001), and more non-smokers know that when a pregnant woman smokes, it can cause the lack of supply of Oxygen{P<0.01). 9. Smoking group and former smoking group have more positive attitude towards smoking than non-smokers and tend to agree to their boy and girl friends' smoking(P<0.001).

• Journal of Environmental Science International
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• v.14 no.12
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• pp.1119-1127
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• 2005

The management of data on biological diversity is presently complex and confusing. This study was initiated to construct a database so that such data could be stored in a data management, and analysis instrument to correct the problems inherent in the current incoherent storage methods. MySQL was used in DBMS(DataBase Management System), and the program was basically produced using Java technology Also, the program was developed so people could adapt to the requirements that are changing every minute. We hope this was accomplished by modifying easily and quickly the advanced programming technology and patterns. To this end, an effective and flexible database schema was devised to store and analyze diversity databases. Even users with no knowledge of databases should be able to access this management instrument and easily manage the database through the World Wide Web. On a basis of databases stored in this manner, it could become routinely used for various databases using this analysis instrument supplied on the World Wide Web. Supplying the derived results by using a simple table and making results visible using simple charts, researchers could easily adapt these methods to various data analyses. As the diversity data was stored in a database, not in a general file, this study makes the precise, error-free and high -quality storage in a consistent manner. The methods proposed here should also minimize the errors that might appear in each data search, data movement, or data conversion by supplying management instrumentation on the Web. Also, this study was to deduce the various results to the level we required and execute the comparative analysis without the lengthy time necessary to supply the analytical instrument with similar results as provided by various other methods of analysis. The results of this research may be summerized as follows: 1)This study suggests methods of storage by giving consistency to diversity data. 2)This study prepared a suggested foundation for comparative analysis of various data. 3)It may suggest further research, which could lead to more and better standardization of diversity data and to better methods for predicting changes in species diversity.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.12
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• pp.929-935
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• 2010

$(1-x)BaTiO_3-x(Bi_{0.5}Na_{0.5})TiO_3$ ($0.01{\leq}x{\leq}0.10$) ceramics were fabricated with muffled sintering by a modified synthesis process. Their positive temperature coefficient of resistivity (PTCR) characteristics were investigated systematically. All specimen showed a perovskite structure with a tetragonal symmetry. Both the lattice parameter of a and c axes were slightly decreased with increasing $(Bi_{0.5}Na_{0.5})TiO_3$ (BNT) content. Grain growth was achieved when the incorporated BNT was increased to 6 mol% and the inhibition of grain growth is considered to be due to the appearance of Ba vacancy ($V^{"}_{Ba}$) in the $(1-x)BaTiO_3-x(Bi_{0.5}Na_{0.5})TiO_3$ ($0.08{\leq}x$). With 4 mol% BNT addition, room temperature resistivity decreased to $48 \Omega{\cdot}cm$ and a resistivity jump ($\rho_{max}/\rho_{min}$) was as high as $1.1{\times}10^4$, respectively. Curie temperature was also increased to $171^{\circ}C$ with increasing BNT content.

• Journal of Broadcast Engineering
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• v.21 no.6
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• pp.957-964
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• 2016

Acquisition of reliable depth maps is a critical requirement in many applications such as 3D videos and free-viewpoint TV. Depth information can be obtained from the object directly using physical sensors, such as infrared ray (IR) sensors. Recently, Time-of-Flight (ToF) range camera including KINECT depth camera became popular alternatives for dense depth sensing. Although ToF cameras can capture depth information for object in real time, but are noisy and subject to low resolutions. Recently, filter-based depth up-sampling algorithms such as joint bilateral upsampling (JBU) and noise-aware filter for depth up-sampling (NAFDU) have been proposed to get high quality depth information. However, these methods often lead to texture copying in the upsampled depth map. To overcome this limitation, we formulate a convex optimization problem using higher order regularization for depth map upsampling. We decrease the texture copying problem of the upsampled depth map by using edge weighting term that chosen by the edge information. Experimental results have shown that our scheme produced more reliable depth maps compared with previous methods.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.19
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• pp.191-223
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• 2003

Electronic commerce and the Internet offer unprecedented opportunities. The explosive expansion of the use of the Internet makes it possible for businesses to expand their markets and render services. Global transaction costs are easy to cut off using Internet and transaction speed is faster than before. Where cyberspace is not free from claims, Offline transaction can lead to problems and disputes the same is for cyberspace transactions. However ADR is not meet for the online transaction for speed, cost and open network system, ODR methods to resolve electronic commerce conflicts is crucial for building confidence and permitting access to justice in an online business environment. The use of the Internet and the network in dispute resolution has an impact on the types of communication implied in the relevant processes such as automated negotiation, online mediation and online arbitration and involves new technological issues such as the integrity and confidentiality of data and communication used to transmit and store data. Among the ODR systems Online Arbitration is currently binding both parties disputed and can achieve the aim of dispute award the same as the traditional arbitration. Arbitration is based on the New York Convention 1958, Arbitration Model law 1985 and national Arbitration Act that are founded on territorial area and rested on arbitration agreement, constitution of the arbitral tribunal, due process, final and binding award and enforcement of the arbitration award. To compare with this issues Online arbitration has unnecessarily legal unstability and risk. ODR is the burgeoning field and has created a new issues. All such issues which have been debated in the ADR are composed with ODR. But these are not limited Some of issues are further complicated by the nature of the online environment such as confidentiality and principle of parties. It is true that online arbitration should comply with legal provisions, but which is impossible to adhere of the law. Flexible translation and functional equivalence of legal provisions are needed for acceptance of electronic commerce disputes. Finally electronic commerce now takes place on the Internet, it is inevitable that the commercial world wants access to dispute resolution process that best suits the new commercial environment. ODR methods are processing for development and legal issues are considered by both national and international authorities. Introduction of new Conventions or amend Convention and Model law of ODR comes near.

• Journal of the Korean Applied Science and Technology
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• v.37 no.4
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• pp.906-914
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• 2020

To investigate the usefulness of natural plants, physicochemical characteristics, functional components and physiological activities of dodder(Cuscuta australis R.Brown) were experimented. The extraction of dodder was carried out at 60℃ in shaking bath with 10 times of distilled water for three hours. Harmful metals such as lead, cadmium and arsenic were not detected, but the content of mercury from dodder was 0.0004ppm in acceptable standards. The extraction yield was 23.45%, total content of phenolics equivalent to gallic acid was 699.8 mg/100g and total content of flavonoid equivalent to naringin was 373.8 mg/100g. 28 kinds of free amino acids were detected with the contents of 252mg/100g in the dodder extract, and the contents of anserine and sarcosine were analysed highest in all amino acids. From the comparison of physiological activities of dodder extract with those of ascorbic acid, total reducing power, electron donating ability based on DPPH radical scavenging and ferric reducing antioxidant power was equivalent to 88%, 56% and 40%, respectively, of ascorbic acid. The nitrite scavenging activity of dodder extract was 78% of ascorbic acid on pH 1.5, but the antioxidant index of dodder on perilla oil was about 4 times greater than that of ascorbic acid.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.2
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• pp.215-223
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• 2018

Intracellular $Ca^{2+}$ mobilization is closely linked with the initiation of salivary secretion in parotid acinar cells. Reactive oxygen species (ROS) are known to be related to a variety of oxidative stress-induced cellular disorders and believed to be involved in salivary impairments. In this study, we investigated the underlying mechanism of hydrogen peroxide ($H_2O_2$) on cytosolic $Ca^{2+}$ accumulation in mouse parotid acinar cells. Intracellular $Ca^{2+}$ levels were slowly elevated when $1mM\;H_2O_2$ was perfused in the presence of normal extracellular $Ca^{2+}$. In a $Ca^{2+}-free$ medium, $1mM\;H_2O_2$ still enhanced the intracellular $Ca^{2+}$ level. $Ca^{2+}$ entry tested using manganese quenching technique was not affected by perfusion of $1mM\;H_2O_2$. On the other hand, $10mM\;H_2O_2$ induced more rapid $Ca^{2+}$ accumulation and facilitated $Ca^{2+}$ entry from extracellular fluid. $Ca^{2+}$ refill into intracellular $Ca^{2+}$ store and inositol 1,4,5-trisphosphate ($1{\mu}M$)-induced $Ca^{2+}$ release from $Ca^{2+}$ store was not affected by $1mM\;H_2O_2$ in permeabilized cells. $Ca^{2+}$ efflux through plasma membrane $Ca^{2+}-ATPase$ (PMCA) was markedly blocked by $1mM\;H_2O_2$ in thapsigargin-treated intact acinar cells. Antioxidants, either catalase or dithiothreitol, completely protected $H_2O_2-induced$ $Ca^{2+}$ accumulation through PMCA inactivation. From the above results, we suggest that excessive production of $H_2O_2$ under pathological conditions may lead to cytosolic $Ca^{2+}$ accumulation and that the primary mechanism of $H_2O_2-induced$ $Ca^{2+}$ accumulation is likely to inhibit $Ca^{2+}$ efflux through PMCA rather than mobilize $Ca^{2+}$ ions from extracellular medium or intracellular stores in mouse parotid acinar cells.

• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.301-308
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• 2009

This paper studied the scheme to realize the manifesto as the method of resolving the side effects after the introduction of the superintendent's election system, a direct election by local residents, in order to implement participative democracy in the educational field. When the superintendent's election system playing an important role in protecting the identity of a state is intruded by the political logic, ideology or factional interest, it leads to the educational crisis such as the damaged independence of the policy and the like. The local educational autonomous system is the institutional arrangement to secure the independence and neutrality of education based on morality and guarantee the democratization and decentralization of educational administration. The scheme to resolve the corrupt aspect of the election of the superintendent is to lead election to the policy-based election. This paper presents the scheme to realize the manifesto movement of the superintendent's electoral campaign to resolve this side effect. All political agents and candidates should be allowed to make free access to diverse information to draw up the manifesto and raise the reliability of the manifesto itself, be guaranteed neutrality, speciality, objectiveness, fairness and the like. In particular, it can be seen that the core task is whether citizens can be involved in the manifesto movement through a shift in their thinking about educational autonomy.