• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.60 no.11
• /
• pp.2083-2087
• /
• 2011

The SiC-$ZrB_2$ composites were produced by subjecting a 40:60 vol.% mixture of zirconium diboride($ZrB_2$) powder and ${\beta}$-silicon carbide (SiC) matrix to spark plasma sintering(SPS). Sintering was carried out for 60sec at $1400^{\circ}C$ (designation as TP145 and TP146), $1500^{\circ}C$(designation as TP155 and TP156) and uniaxial pressure 50MPa, 60MP under argon atmosphere. The physical, electrical, and mechanical properties of the SiC-$ZrB_2$ composites were examined. The relative density of TP145, TP146, TP155 and TP156 were 94.75%, 94.13%, 97.88% and 95.80%, respectively. Reactions between ${\beeta}$-SiC and $ZrB_2$ were not observed via x-ray diffraction (hereafter, XRD) analysis. The flexural strength, 306.23MPa of TP156 was higher than that, 279.42MPa of TP146 at room temperature, but lower than that, 392.30MPa of TP155. The properties of a SiC-$ZrB_2$ composites through SPS under argon atmosphere were positive temperature coefficient resistance (hereafter, PTCR) in the range from $25^{\circ}C$ to $500^{\circ}C$. The electrical resistivities of TP145, TP146, TP155 and TP156 were $6.75{\times}10^{-4}$, $7.22{\times}10^{-4}$, $6.17{\times}10^{-4}$ and $6.71{\times}10^{-4}{\Omega}{\cdot}cm$ at $25^{\circ}C$, respectively. The densification of a SiC-$ZrB_2$ composite through hot pressing depend on the sintering temperature and pressure. However, it is convinced that the densification of a SiC-$ZrB_2$ composite do not depend on sintering pressure under SPS.

• International Commerce and Information Review
• /
• v.1 no.2
• /
• pp.145-165
• /
• 1999

With the rapid spreading of the internet that is based on the development of the information network system, the paradigms of "internet round" and "cyber" are given much weight in the notion of "market." Especially, the cyber shopping for the individuals is developing rapidly creating the new life style, and also in the domestic economy the cases of building and running the cyber shopping malls are increasing. The purpose of this study is to analyse the customers' shopping styles that can be shown when the customers purchase physical goods or digital goods at the B to C EC and find the way to activate the shopping malls by controlling the factors which influence the trade. The result of the study is as follows: First, to analyse the acting style of the customers at the B to C EC, it is searched whether there is any relationship between the purchasing goods, which are divided into physical goods and digital goods. There was a cross analysis between the first factor of the five factors of the purchase decision or delay at the B to C EC and the goods type. The result of the analysis is that the purchase decision factor is different according as what type of goods is purchased. On the other hand, the purchase delay factor has no relation with the goods type. Second, the fact that the cyber shopping activities are quite different according to sexuality, age, academic background, or occupation suggests that these factors are very important to the strategy for the market-specification of the B to C EC marketing construction. The result shown in this study is sure to give great help to figure out the improvement strategies and the market-specialization strategies to accelerate the B to C EC marketing. On the side of the strategies for the improvement of the goods services, more attention should be given to the functional side for the improvement of the reliability of the goods service such as capacity, technique, and quality. And the activities of the customers are so different according to the vital statistics that the way to cope with the changeability properly should be considered.

• Journal of the Korean Wood Science and Technology
• /
• v.23 no.3
• /
• pp.66-72
• /
• 1995

The rate of fixation of the components were evaluated in CCA-Type B and CCFZ-treated radiata pine sapwood by quantitative analysis of solution expressed from the treated wood. The leaching characteristics of radiata pine blocks treated with CCA-Type B and CCFZ were also evaluated by the AWPA standard leaching test. Both fixation and leaching charactersistics of CCA-Type B were compared with CCA-Type C treated wood samples. The rate of CCA-Type B fixation was a little faster than that of CCFZ. However, significant amounts of arsenic was unfixed in the CCA-Type B treated samples and consequently leached. These significant quantities of arsenic liberated from the CCA-Type B treated wood during service may pose some environmental concerns. Arsenic was no longer detectable from CCA-Type C treated samples when fixation was complete, even though the fixation of CCA-Type C was slower in some degree than CCA-Type B. In summary, it could be said that CCFZ was much safer preservative than CCA-Type B by the criterion based on the relative hazard assessed by absolute amount of unfixed element present in the treated wood. Also the decision that CCA preservative has to move from Type B to Type C should be made sooner or later for continuous use of CCA preservative in the future.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.14 no.4
• /
• pp.182-193
• /
• 2011

In order to compare the spatio-temporal variation pattern of sea surface temperature (SST) in Korea's Southern areas of the sea according to a regional scale, this study has selected the winter and summer seasons for 31 years (1980~2010) in a period aspect and selected three areas of the sea such as the Western areas of the sea (region B) and Eastern areas of the sea (region C) around Jeju Island in addition to overall Southern areas of the sea (region A) in regional aspect. The regression analysis was applied to find out a temporal variation pattern of SST, and the weighted mean center (WMC) of SST as well as analysis of a standard deviational ellipse (SDE) was respectively applied. As a result of regression analysis of SST, it showed a rising long-term trend for all two seasons in three regions. However, though the average SST for 31 years was all similar in three regions in the summer season, the region C appeared more highly than region B in the winter season. The spatial variation pattern of SST for two seasons showed that it is respectively different from each other in three regions. The spatial variation pattern of SST appeared as E-W direction in region A, SE-NW direction in region B and SW-NE direction in region C. In addition, the relationship between the location of the WMC of SST and the average SST showed correlation in regions A and B in the winter season, whereas it appeared that there is no correlation in region C. Accordingly, it can be known that the regional scale should be considered in case of analysis of spatio-temporal variation patterns of SST.

• Journal of Powder Materials
• /
• v.20 no.5
• /
• pp.366-370
• /
• 2013

The effects of $B_4C$ on the mechanical properties of WC/Ni-Si hardmetal were analyzed using sintered bodies comprising WC(70-x wt.%), Ni (28.5 wt.%), Si (1.5 wt.%), and $B_4C$ (x wt.%), where $$0{\leq_-}x{\leq_-}1.2$$ wt.%. Samples were prepared by a combination of mechanical milling and liquid-phase sintering. Phase and microstructure characterizations were conducted using X-ray diffractometry, scanning electron microscopy, and electron probe X-ray micro analysis. The mechanical properties of the sintered bodies were evaluated by measuring their hardness and transverse rupture strength. The addition of $B_4C$ improved the sinterability of the hardmetals. With increasing $B_4C$ content, their hardness increased, but their transverse rupture strength decreased. The changes of sinterability and mechanical properties were attributed to the alloying reaction between $B_4C$ and the binder metal (Ni, Si).

• Korean Journal of Soil Science and Fertilizer
• /
• v.34 no.5
• /
• pp.311-315
• /
• 2001

In order to improve a soil test-based fertilization model for nitrogen, the Mitscherlich-Baule-Spillman equation modified by Bray and his coworkers was introduced and tested for its possibility of application. The coefficients $C_1$ and $C_2$ in the equation A were calculated by applying 10 pot experimental results done by the National Institute of Agricultural Sciences and Technology. Then, a regression(B) between C_1 and x, the fertilizer level was estimated. log(Ymax-Y) = logYmax-$C_1x-C_2b$ (A) where Ymax : maximum yield. Y : yield without or with a limited amount of fertilizer applied, x : application level of fertilizer, b : content of a nutrient in soil, $C_1$ and $C_2$ : coefficients of x and b, respectively. log(0.05)=$-C_1x-C_2b$ (B) Fertilizer requirement calculated by the equation B was significantly correlated with the real level of fertilizer applied for 95 percentage of the maximum yield. A more extensive and precise study on $C_1$ and $C_2$ in the equation A in expected to improve significantly the fitness of soil analysis to the fertilizer recommendation.

• Journal of Animal Science and Technology
• /
• v.49 no.5
• /
• pp.549-558
• /
• 2007

C4B and BAT2, assigned to the SLA class III region, were recently reported on relation with human diseases. The primers for RT-PCR and RACE-PCR for CDS analysis of these genes of pig were designed by aligning the CDSs of humans and mice from GenBank. After we amplified and sequenced with these primers and cDNAs, the full-length CDSs of pig were determined. The CDS lengths of C4B and BAT2 were shown as 5226 bp and 6501 bp. In addition, the identities of nucleotide sequences with human and mouse were 76% to 87%, and the identities of amino acids were 72% to 90%. After we carried out the alignment with determined CDSs in this study and pig genomic sequences from GenBank, the primers for cSNP detection in genome were designed in intron regions that flanked one or more exons. Then, we amplified and directly sequenced with genomic DNAs of six pig breeds. Four cSNPs from C4B and three 3 cSNPs from BAT2 were identified. In addition, amino acid substitution occurred in six cSNP positions except for C4248T of C4B. By the Multiplex-ARMS method, we genotyped seven cSNPs with DNA samples used for direct sequencing. We verified that this result was the same as that analyzed using direct sequencing. To demonstrate recrudescence, we performed both direct sequencing and Multiplex-ARMS on two randomly selected DNA samples. The genotype of each sample showed the same result from both methods. Therefore, seven cSNPs were identified from C4B and BAT2 and could be used as the basic data for haplotype analysis of SLA class III region. Moreover, the Multiplex-ARMS method should be powerful for genotyping of genes assigned to the whole SLA region for the xenograft study.

• Journal of Distribution Science
• /
• v.21 no.12
• /
• pp.91-102
• /
• 2023

Purpose: This study analyzed the structural relationship between interaction quality and relationship satisfaction, towards providing managerial implications for effective relationship management in the B2B market. Research design, data and methodology: The following survey was conducted only if respondents had used the airline's B2C more than twice. A total of 398 copies were collected and empirical analysis was conducted using AMOS 18.0 and PASW 18.0. Results: The flexibility, quickness, and fairness that make up the interaction quality in airline B2C have been shown to have a significant impact on trust, relationship performance and relationship satisfaction. Conclusions: Usefulness, quickness, and fairness, which are sub-variables of airline B2C mutual quality, have a positive effect on trust. In addition, trust was found to have a positive effect on relationship performance and relationship satisfaction. We draw implications for the importance of interaction quality in order to strengthen and sustain relationships with users in the airline B2C distribution market. In addition, in order to build meaningful relationship performance and relationship satisfaction, interaction quality and trust level should be examined first, and interaction quality improvement should be the top goal.

• Asian-Australasian Journal of Animal Sciences
• /
• v.26 no.2
• /
• pp.163-170
• /
• 2013

In order to analyze the genetic diversity and phylogenetic status of the Korean Chikso breed, we determined sequences of mtDNA cytochrome b (cyt b) gene and performed phylogenetic analysis using 239 individuals from 5 Chikso populations. Five non-synonymous mutations of a total of 15 polymorphic sites were identified among 239 cyt b coding sequences. Thirteen haplotypes were defined, and haplotype diversity was 0.4709 ranging from 0.2577 to 0.6114. Thirty-five haplotypes (C1-C35) were classified among 9 Asia and 3 European breeds. C2 was a major haplotype that contained 206 sequences (64.6%) from all breeds used. C3-C13 haplotypes were Chikso-specific haplotypes. C1 and C2 haplotypes contained 80.5% of cyt b sequences of Hanwoo, Yanbian, Zaosheng and JB breeds. In phylogenetic analyses, the Chikso breed was contained into B. taurus lineage and was genetically more closely related to two Chinese breeds than to Korean brown cattle, Hanwoo. These results suggest that Chikso and Hanwoo have a genetic difference based on the mtDNA cyt b gene as well as their coat color, sufficient for classification as a separate breed.

• Journal of Korean Society of Forest Science
• /
• v.99 no.6
• /
• pp.808-815
• /
• 2010

This study is to give informations about management Situations and investment returns to someone who will newly cultivate schizandra or expand area of culture. This study used IRR, B/C Ratio and NPV for beneficial analysis. We surveyed fifty one among schizandra cultivation farmhouses in chief producing districts Gangwon Inje, Gyeongbuk Munkyung, Kyungnam Sancheong and Jeonnam Whasoon in Korea from May till September in 2009. So this study surveyed about inputted labors and materials, land price and etc. by working process to calculate producing and operating cost. Fruits of schizandra are sold from 5,000 won to 6,000 won per kg at locals. And IRR(Internal Rate of Returns), B/C Ratio and incomes ratio is calculated by three senarios 5,000 won, 5,500 won and 6,000 won per kg at locals. Discount rate is 3.00%. As the result of this study IRRs are -16.00%, -6.91%, 0.40% one after another and B/C Ratios are 0.81, 0.89, 0.97 one after another. And schizandra cultivation isn't profitable. When price of schizandra fruits is 6,200 won per kg, IRR is 3.00% and B/C Ratio is 1.00. Therefore, if price of schizandra fruits is over 6,200 won per kg, we judge that it is profitable. And income ratio is 23.9% on 6,200 won per kg.