• Carbon letters
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• v.8 no.4
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• pp.299-306
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• 2007

Four stream- activated carbons were prepared by carbonizing apricot stones at $600^{\circ}C$ followed by gasification with steam at $950^{\circ}C$ to burn-off's=17, 32, 49 and 65%. The textural parameters of these activated carbons were determined from nitrogen adsorption results at 77 K. The total pore volume and the mean pore radius increased with the increase of % burn-off whereas the surface area increased with the increase of burn- off from 17 to 32 and further to 49%. Further increase of burn-off to 65% was associated with a considerable decrease in surface area as a result of pronounced pore widening due to pore erosion. The surface pH values of the carbons investigated range between 7.1 and 8.2. The adsorption of oxamyl onto the activated carbon followed pseudo-second order kinetics and the equilibrium adsorption isotherms fitted Langmuir adsorption model. The adsorption of oxamyl proved to be of the physical type and took place in non-micropores. The amount of oxamyl adsorbed expressed as $q_m$ depends to a large extent to the surface area located in non-micropores $S^{\propto}\;_n$, where a straight line relationship passing through the origin was obtained.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.9
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• pp.104-113
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• 1994

We have fabricated n-p-n HBTs using 3-inchAlgaAs/GaAs hetero structure epi-wafers grown by MBE. DC and AC characteristics of HBT devices were measured and analyzed. For HBT epi-structure, Al composition of emitter was graded in the region between emitter cap and emitter. And base layer was designed with concentration of 1${\times}10^{19}/cm^{3}$ and thickness of 50nm, and Be was used as the p-type dopant. Principal processes for device fabrication consist of photolithography using i-line stepper, wet mesa etching, and lift-off of each ohmic metal. The PECVD SiN film was used as the inslator for the metal interconnection. HBT device with emitter size of 3${\times}10{\mu}m^{2}$ resulted in cut-off frequency of 35GHz, maximum oscillation frequency of 21GHz, and current gain of 60. The distribution of the ideality factor of collector and base current was very uniform, and the average values of off-set voltage and current was very uniform, and the average values of off-set voltage and current gain were 0.32V and 32 within a 3-inch wafer.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.499-505
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• 2017

Photoisomerizing molecules which can transform their structure by the light irradiation have great deal for the application of photo-switching devices. And azobenzene is the representive type of the photoisomerizing molecules. It can transform their trans- structures into cis- structure as the light for certain wave lengths they receive. This property shows the potential of ON/OFF switching functionalization which can be used into the nano scale photo switch. Furthermore, many studies are interested in the organic linkers that connect the azobenzene and metal electrodes. We used S, $CH_2S$, $(CH_2)_4S$ as the linker to watch the influence of linkers for electronic properties. So We suggest a photoswitching device based on the vertical junction using the first-principles calculations with density functional theory and non-equilibrium Greens function (NEGF). By analyzing the electronic structure and tunneling current caused by the structural difference of the system between cis- and trans- azobenzene, the difference in switching mechanism, ON/OFF ratio and transmission will be watched as the linker changes. And finally We will suggest which linker would be the better for the optimal device architecture which can achieve high control of the ON/OFF photocurrent ratio. This result will show the potential of azobenzene-based photoswitch and provide the critical insight in constructing the optimal device architecture.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.11
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• pp.1527-1576
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• 2002

Quick Response based Mass-Customization can be produced and distributed customized goods and services on mass basis in apparel e-business. Because consumers can: t touch and feel the apparel products in e-business, they tend to have the negative buying behavior. The purpose of this study is to investigate the differences of consumer's texture sensibility of apparel products based on marketing channels (on-line/off-line). Two types of questionnaires for on-line and of f-line were used to assess consumer sensibility on apparel fabric. The 8 swatches were selected in regard to the previous literatures. 205 questionnaires for each type (on-line/off-line) were distributed. Statistical devices were t-test, mean and standard deviation with SPSS10.0. The result of this study was showed that there were partially significant differences on consumers' texture sensibility on apparel products between on-line and off-line. Under on-line environment, consumers perceived corduroy as warm, strong, and sandy. taffeta as warm, sandy, and glossy, denim as sandy, and warm, organza as sandy, and thin, satin as sandy, dense, and modern, chiffon as sandy, and flat, velvet as warm, and soft, single jersey as warm, soft, and comfortable. Therefore, apparel firms cooperating based Mass-Customization in e-business have to pay attention to the differences on consumers’ texture sensibility of on-line apparel products from those of off-line.

• Journal of Distribution Science
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• v.15 no.6
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• pp.5-12
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• 2017

Purpose - This study is to investigate the effects of consumption values of retailers on the importance of store attributes, and to determine the influence on the consumption values of consumers who shop at complex shopping malls on the empirical and functional attributes in those malls as well as on the influence of on/off-line channels. Research design, data, and methodology - With 344 surveyed questionnaires, this study was conducted by using SPSS 22.0 to verify the reliability and validity of the measured variables. Structural equation model (SEM) was employed as a statistical method for the hypotheses test of this study. Results - The results showed that hedonic value has more influence on the importance of empirical attribute than that of functional attribute in shopping malls. In addition, practical value has more influence on functional attributes than empirical properties of shopping malls. However, these relationships showed the difference in on/off-line channels. As for off-line channels, consumers' consumption values were more influential on empirical attributes, while functional attributes were more important in on-line channels Conclusions - This study analyzed the influence on the importance of the consumption values in store attributes, and the effects of each channel with suggesting practical implications.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.6
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• pp.575-579
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• 2004

Package reliability test was conducted to investigate the effect of solder paste composition at BGA Package. It was found that the shape and size of the phase form are affected by the processing parameters. The material have used to fill in the via was Sn/36Pb/2Ag and Sn/0.75Cu type solder paste. Sn/36Pb/2Ag and Sn/0.75Cu paste were fabricated on Tape-BGA substrates by screen printing process, and via ball mount data were characterized with variations of dwell time of 85 seconds at reflow peak temperature at 22$0^{\circ}C$ or 24$0^{\circ}C$. The test condition was MRT 30 $^{\circ}C$/60 %RH/96 HR. Failures formed of a ball-off in solder paste process were observed by using a Optical Microscope and SEM(Scanning Electron Microscope). It was concluded that intermetallic layer growth played important roles in increasing solder fatigue strength for addition of Ag composition. The degradation of shear strength of solder composition is discussed.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.4
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• pp.444-451
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• 2009

The price increase of natural resources and the worldwide growth of LNG demand led to save the waste of Boil-Off Gas evaporating from cargo tanks of LNG carriers during navigation. As one of the efforts, a BOG reliquefaction system with BOG-to-BOG heat exchanging method was newly devised. This study was also discussed on the process details such as some features and advantages including comparisons with conventional BOG reliquefaction system, non BOG-BOG heat exchange type. The thermodynamic analysis for the system were also performed. Through the cycle simulation, the process efficiency of the BOG reliquefaction system BOG-BOG heat exchange was estimated to be increased up to 21%.

• Journal of the Korean Society of Food Culture
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• v.37 no.2
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• pp.109-118
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• 2022

This study was undertaken to compare meal skipping, snacking, and weight perceptions between students on-campus living alone and off-campus living with parents, in an urban college in the United States. The self-report survey was completed by 219 college students (on-campus=100, off-campus=119) between April and May 2012. Two-thirds (67%) of the respondents skipped at least one meal in the past week, and most participants showed strong desires to lose weight despite their normal/under-weight status. Significant differences between the two groups were obtained for the reason to skip a meal and the type of snack consumed. Compared to on-campus students, significantly higher values were obtained for off-campus students for choosing 'no time to prepare' as a meal skipping reason for lunch and dinner, and 'sweets' as a preferred snack. In addition to the group comparison, multiple regression results indicate that the body mass index (BMI) positively correlates with meal skipping and snacking frequencies. Younger students and female students were determined to have a higher frequency of meal skipping and morning snacking. Future research is required to study the dietary factors associated with living arrangements, to help college students develop healthy eating habits.

• Animal cells and systems
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• v.3 no.2
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• pp.149-151
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• 1999

It has been suggested that the bush warbler (Cettia diphone borealis) uses different song types in various situations. We analyzed song features and conducted playback experiments in order to reveal the function of songs of the bush warbler. Two song types were identified. The short song type has a shorter song duration than that of normal song types and consists of only one or two syllables. Due to its short syllable and low amplitude of the whistle portion, we were able to discriminate the short song type (S song type). from the normal song type (N song Type). In the playback experiments, bush warblers sang high rates of short song type for the first three minutes after playback. After 6 minutes of playback, males changed to singing normal songs. These results suggest that the short song of the bush warbler may function to threaten or drive off intruding males.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.12
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• pp.897-901
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• 2010

A silencer has been widely used for the purpose of suppressing the noises propagated from duct of air conditioning system. The absorption type silencer is usually applied to reduce the noise with high frequency bandwidth. On the order hand, the resonance type silencer is applied to reduce the noise with low-middle frequency bandwidth. The insertion loss of silencer is measured in the reverberation room. The cut-off frequency of reverberation room is 100 Hz. The insertion loss of absorption type silencer is more larger than that for resonance type silencer regardless of changing the flow velocity.