• 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.

• Korean journal of food and cookery science
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• v.24 no.4
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• pp.536-541
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• 2008

In order to determine the effects of strawberry powder on the baking quality of cakes, yellow layer cakes were prepared with four freeze-dried strawberry powders substitutes, at levels of 0%, 1%, 2%, 3%, 4% and 5%. Then, the physical properties, baking properties and sensory characteristics of the finished cakes were assessed. The cakes were stored for 6 days at $22^{\circ}C$ and the change in hardness during storage was evaluated. The Viscosity of the doughs, as well as the specific gravity, increased as the amount of strawberry powder in the flour increased. The volume indices of the strawberry powder cakes were less than that of control, but the other indices did not differ from those of the controls. The crust color of the strawberry cakes evidenced a reduction in L. a and b values. The crumb color also evidenced a reduction in the L and b values, but the a values increased. Sensory characteristics were evaluated by 60 students from the Dept. of Food and Biotechnology. Crust color, crumb color, moistness, softness, taste and overall acceptance were measured via a 5-scale acceptance test. The crust color of cakes containing more than 3% strawberry powders and the crumb color of all strawberry cakes evidenced lower scores than the controls. Cakes containing 5% strawberry powders were least acceptable in terms of overall characteristics. Although cakes prepared with flour containing up to 4% strawberry powder were less acceptable than the controls, general sensory scores ranged in an average${\sim}$like range. The incorporation of strawberry power into cakes was shown to increase the overall hardness.

• Korean Journal of Social Welfare
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• v.66 no.4
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• pp.53-75
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• 2014

The current status of Korean social work can be summarized as multiple complexities and ambiguities not only in ideological but in practical aspects. Although they have long been considered as an unique feature of social work as one of representative human service professions, the extent of such complexities are now reaching the culmination enough to raise the questions about the very nature of social work practice. This study aims to analyse such ambiguities and complexities around the field of social work in a systematic ways with the theory of liquid modernization, an creative framework for modern society, coined by Zygmunt Bauman who is now considered as one of the leading sociologist and thinker. The study shows clearly that social work in Korea is nowadays entering the phase of liquid modern society and specific features of liquidity of modern society such as consumerism, privatization, corruption of publicity etc are founded in the areas of social work. To make it worse, social work are thinking about the anachronical response to this flow of liquidity by selecting the strategies useful in solid modern era, not in the liquid one. In this context, the study suggests that social work practice have to prepare to adequate measures to secure its own autonomy and sustain genuine identification from the ruthless melting power of liquid modern society.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.2
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• pp.149-158
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• 1998

The SAR patterns of biological objects contacted with coaxial waveguide antennal has been investigated, in which the biological object was modeled by a homogeneous and four-layered lossy human body. We derived the finite-difference time-domain(FDTD) algorithm and equation of MUR and generalized perfectly matched layer(GPML) ABCs in cylindrical coordination. The coupling between coaxial waveguide antenna and a biological object was analyzed by use of MUR and GPML ABCs in the FDTD method to obtain the absorbed power patterns in the media. The specific absorption rates (SAR) distribution which was corresponding to the temperature distribution was calculated in each region by use of the steady-state response in the FDTD method. The SAR patterns of the FDTD method using MUR absorbing boundary conditions(ABCs) was compared with those of the FDTD method using GPML ABCs. The comparison exhibits that the penetration depth of the SAR patterns using MUR ABCs is deeper than that of the SAR patterns using GPML ABCs because of loss in free space. However, the spread in the lateral directions of the SAR patterns using GPML ABCs is smaller than of the SAR patterns using MUR ABCs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.4
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• pp.819-830
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• 2017

An FM radio based PCL system is a passive radar technique for detecting the multiple moving targets from FM radio signals and tracking the trajectories of the targets by calculating the cross-correlation function of direct-path signal and target echo signals. However, the interference signals are received from a surveillance channel, which is designed to receive the target echo signals. Because of this problem, the target echo signals are masked by the strong interference signals and this makes it difficult to detect the true targets from the cross-correlation function. Adaptive filters are known as effective methods for suppressing the interference signals but there is a problem to present their accurate performances in the PCL system because many literatures used the cross-correlation function and the ratio of input and output power as a measure of the performance analysis. In this paper, a performance analysis method is proposed to evaluate the performance of interference cancellation algorithms. By using the property that each component of the filter weight vector is adjusted to suppress the specific interference signal, a performance measure of the interference signal suppression is defined by a function of adaptive filter weights. Based on the proposed method, we compare the performance of the adaptive filters used in the PCL system. Simulation results show that the proposed method can be very effective for evaluating the performance of interference cancellation algorithms.

• Journal of the Korean Solar Energy Society
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• v.32 no.4
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• pp.24-33
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• 2012

Recently, finishing materials at spandrel area, a part of curtain-wall system, are gradually forced to improve thermal insulation performance in order to enhance the building energy efficiency. Also, Building Integrated Photovoltaics(BIPV) systems have been installed in the exterior side of the spandrel area, which is generally composed of windows. Those BIPVs aim to achieve high building energy efficiency and supply the electricity to building. However, if transparent BIPV module is combined with high insulated spandrel, it would reduce the PV efficiency for two major reasons. First, temperature in the air space, located between window layer and finishing layer of the spandrel area, can significantly increase by solar heat gain, because the space has a few air density relative to other spaces in building. Secondly, PV has a characteristics of decreased Voltage(Voc and Vmp) with the increased temperature on the PV cell. For these reasons, this research analyzed a direct interrelation between PV Cell temperature and electricity generation performance under different insulation conditions in the spandrel area. The different insulation conditions under consideration are 1) high insulated spandrel(HIS) 2) low insulated spandrel(LIS) 3) PV stand alone on the ground(SAG). As a result, in case of 1) HIS, PV temperature was increased and thus electricity generation efficiency was decreased more than other cases. To be specific, each cases' maximum temperature indicated that 1) HIS is $83.8^{\circ}C$, 2) LIS is $74.2^{\circ}C$, and 3) SAG is $66.3^{\circ}C$. Also, each cases yield electricity generation like that 1) HIS is 913.3kWh/kWp, 2) LIS is 942.8kWh/kWp, and 3) SAG is 981.3kWh/kWp. These result showed that it is needed for us to seek to the way how the PV Cell temperature would be decreased.

• Journal of Digital Convergence
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• v.14 no.11
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• pp.379-388
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• 2016

This study was aimed at identifying the actual state of workplace violence based on a survey conducted to 876 subway workers in Seoul and determining the relationship between workplace violence and mental health of workers. Data were collected via web site, using a structured questionnaire and for the analysis of the data, a multiple linear regression analysis was carried out by the statistical program SPSS 20.0. According to the results, the perpetrators of violence turned out to be "passengers" in all types of workplace violence: physical violence, verbal violence, sexual harassment and disregard for personality. As for the relationship between workplace violence and the mental health of the workers, statistically significant differences were shown between all the above mentioned workplace violence types and sub-areas of mental health. Also, as for the impact of workplace violence on the mental health of the workers, significant differences were found in physical violence, sexual harassment and disregard for personality, with 8.3 percent of explanatory power. Based on these findings, the study suggests the establishment and the application of customer interaction guidelines to protect subway workers from workplace violence along with specific measures customized for each work environment to prevent violence.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.2
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• pp.165-182
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• 2001

In this paper, we describe a design and implementation of the Wireless Markup Language(WML) compiler to deploy wireless Internet services effectively. The WML compiler translates textual WML decks into binary ones in order to reduce the traffic on wireless links that have relatively low bandwidth to wireline links and mitigate the processing overhead of WML decks on, wireless terminals that have relatively low processing power to fixed workstations. In addition, it takes over the overhead of eXtensible Markup Language(XML) well-formedness and validation processes. The WML compiler consists of the lexical analyzer and parser modules. The granunar for the WML parser module is LALR(1) context-free grammar that is designed based on XML 1.0 and WML 1.2 DTD(Document Type Definition) with the consideration of the Wireless Application Protocol Binary XML grammar. The grammar description is converted into a C program to parse that grammar by using parser generator. Even though the tags in WML will be extended or WML DTD will be upgraded, this approach has the advantage of flexibility because the program is generated by modifying just the changed parts. We have verified the functionality of the WML compiler by using a WML decompiler in the public domain and by using the Nokia WAP Toolkit as a WAP client. To measurethe compressibility gain of the WML compiler, we have tested a large number of textual WML decks and obtained a maximum 85 %. As the effect of compression is reduced when the portion of general textual strings increases relative to one of the tags and attributes in a WML deck, an extended encoding method might be needed for specific applications such as compiling of the WML decks to which the Hyper Text Markup Language document is translated dynamically.

• Food Science and Preservation
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• v.21 no.5
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• pp.668-675
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• 2014

This study investigated the quality characteristics and antioxidant activity of muffins prepared with different amounts (0%, 5%, 10%, and 15%) of aronia powder. The moisture content was higher in the groups that contained aronia powder than in the control muffin. The specific volume of the muffins was lowest in the group with 15% aronia powder added. The lightness and yellowness values decreased, while the redness values increased with increasing amounts of the aronia powder. The hardness of the control group was lower than that of the 10% and 15% treatment groups. The consumer acceptance test revealed no significant differences in the taste and texture of the muffin samples, but the overall acceptability scores were lowest for the muffins with 15% aronia powder added. The substitution of wheat flour for the aronia powder yielded muffins with a higher polyphenol content and total flavonoid content. The antioxidant activity measured via the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, metal chelating effect, and reducing power increased as the concentration of the aronia powder increased. The results showed that up to 10% aronia powder can be incorporated into muffins to meet the sensory quality and functional needs of consumers.

• The KIPS Transactions:PartD
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• v.8D no.1
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• pp.32-43
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• 2001

Due to the limitation of data modeling power and the view update ambiguity, relational view is limitedly used for engineering applications. On the contrary, object-oriented database view would playa vital role in defining custom interface for engineering applications because the above two limitations of the relational view are overcome by the object-oriented view. Above all, engineering application data interface should fully support updates. More specifically, updates against the data interface needs to be unambiguously defined and its semantic behavior should be equal to base schema updates'. For this purpose, we define the notion of update semantic preserving which means that view updates displays the same semantics as base schema. Besides, in order to show the feasibility of this characteristics, specific and concrete algorithms for update preserving updates are presented for a CAD specialized object-oriented database view - MultiView. This paper finds that in order that virtual classes coudld form a schema with 'isa' relationships rather than just a group of classes, the update semantics on the virtual classes should be defined such that the implied meaning of 'isa' relationships between classes are not to be violated. Besides, as its sufficiency conditions, we derived the update semantics and schema constituable conditions of the virtual classes that make view schemas look like base schemas. To my best knowledge, this is the first research that presents the sufficiency conditions by which we could defined object-oriented views as integrated schemas rather than as separate classes.