• Journal of The Korean Association For Science Education
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• v.18 no.2
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• pp.127-136
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• 1998

The purpose of this study was to develop, field test an instrument to assess secondary school students' conceptions of the nature of science. The instrument named Philosophical Perspectives Probe(PPP) is a pool of 24 multiple-choice items that address a wide range of philosophical topics of science. The statements and the choices of this instrument were derived from an analysis of various philosophical positions. The main philosophical systems of the instrument are inductivism, falsificationism, and relativism, respectively. Major distinctions depend on the issues of the criteria of demarcation, patterns of scienctific change, epistemological status of scientific knowledge, and the scientific methods. The researchers also offer teachers a new way of assessing and interpreting their students' conceptions on a wide variety of topics related to the nature of science.

• Culinary science and hospitality research
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• v.16 no.3
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• pp.66-75
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• 2010

The purpose of this study is to examine the competitive positions of five coffee shop brands(i.e., Starbucks, Coffee Bean & Tea Leaf, Hollys, Angelinus, and Tom N Toms) in Korea. For this study, data were gathered from the residents of Seoul, Busan and Daegu from September 22 to October 11, 2009. In order to accomplish the purpose of the study, MDS was utilized to investigate differences in customer's perception of the position of five coffee shop brands. The results of positioning analysis showed that there was competitive relationship between Hollys and Angelinus. Also, the positioning of Tom N Toms was close to Hollys and Angelinus. However, Starbucks, the market leader, and Coffee Bean & Tea Leaf, the market follower, were their own identity in their brands. According to the result of the study, it will be helpful for the marketers who need to establish a marketing strategy. Future studies could include other various variables and more thorough investigation into them.

• Journal of Korean Institute of Industrial Engineers
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• v.26 no.2
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• pp.88-94
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• 2000

For efficient operation, vital hand controls must be easily controlled by the operator from his or her normal working position. The primary working area based on the operator-perceived working comfort was developed to serve as a design guideline to the control panel layout. Six male and four female subjects voluntarily participated in the experiment in which working comfort was measured for two types of controls - knob and lever. The operator-perceived working comfort was examined for the frontal and sagittal distances from the body center and the slope of a work surface. The response surface methodology using a central composite design was employed to develop a prediction model for operator's working comfort on each type of controls. The proposed working areas based on the actual working comfort of an operator avoided the dichotomy that considers only the reachability of control devices, and showed a distinct shape, when compared to the existing normal working areas following the Farley's concept. It was shown that the distance from the body to control devices and the slope of a work surface have a quadratic relationship to the working comfort, and that the most comfortable area for seated tasks is located at the distance of about 2∼4 cm in the sagittal direction and about 42∼43 cm in the frontal direction from the shoulder, respectively. It was also found that the working comfort varies within the working area even at the positions with an equal distance from the body. It is expected that the isocomfort working area generated in the study will be used as a useful guideline for control panel layout.

• Journal of Korea Game Society
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• v.7 no.3
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• pp.89-96
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• 2007

The domestic game industry is diversifying itself in terms of game contents. The existing contents have limits when it comes to satisfy various needs and tastes of users. A scenario which successfully absorbs the players and users of a game may affect the whole game structure. Companies also introduce new contents to seize new customers. Thus, contents are considered more important than the past. Now that companies are able to produce various forms of contents and products out of one specific content, the development of new, user-satisfying contents can affect other fields of the industry. Thus, they are now found in one of the top positions in the business hierarchy. But game developers and experts concentrate more on other factors and environments of games, slowing down the growth of contents development. Therefore, this study focuses more on contents as an essential attribute to game production, especially scenario making. How changing results of a synopsis, as a part of a scenario, affect the preference of game users was the main focus of the study. The result of the study should suggest a positive direction for contents and scenario development.

• Geomechanics and Engineering
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• v.12 no.3
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• pp.361-397
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• 2017

The unloading effect from excavations can cause the deformation of adjacent tunnels, which may seriously influence the operation and safety of those tunnels. However, systematic studies of the deformation characteristics of tunnels located along side excavations are limited, and simplified methods to predict the influence of excavations on tunnels are also rare. In this study, the simulation capability of a finite element method (FEM) considering the small-strain characteristics of soil was verified using a case study. Then, a large number of FEM simulations examining the influence of excavations on adjacent tunnels were conducted. Based on the simulation results, the deformation characteristics of tunnels at different positions and under four deformation modes of the retaining structure were analyzed. The results indicate that the deformation mode of the retaining structure has a significant influence on the deformation of certain tunnels. When the deformation magnitudes of the retaining structures are the same, the influence degree of the excavation on the tunnel increased in this order: from cantilever type to convex type to composite type to kick-in type. In practical projects, the deformation mode of the retaining structure should be optimized according to the tunnel position, and kick-in deformation should be avoided. Furthermore, two methods to predict the influence of excavations on adjacent tunnels are proposed. Design charts, in terms of normalized tunnel deformation contours, can be used to quantitatively estimate the tunnel deformation. The design table of the excavation influence zones can be applied to determine which influence zone the tunnel is located in.

• Computers and Concrete
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• v.20 no.5
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• pp.605-616
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• 2017

Concrete filled steel tubular (CFST) composite girder is a new type of structures for bridge constructions. The existing design codes cannot be used to predict the thermal stress in the CFST truss girder structures under solar radiation. This study is to develop the temperature gradient curves for predicting thermal stress of the structure based on field and laboratory monitoring data. An in-field testing had been carried out on Ganhaizi Bridge for over two months. Thermal couples were installed at the cross section of the CFST truss girder and the continuous data was collected every 30 minutes. A typical temperature gradient mode was then extracted by comparing temperature distributions at different times. To further verify the temperature gradient mode and investigate the evolution of temperature fields, an outdoor experiment was conducted on a 1:8 scale bridge model, which was installed with both thermal couples and strain gauges. The main factors including solar radiation and ambient temperature on the different positions were studied. Laboratory results were consistent with that from the in-field data and temperature gradient curves were obtained from the in-field and laboratory data. The relationship between the strain difference at top and bottom surfaces of the concrete deck and its corresponding temperature change was also obtained and a method based on curve fitting was proposed to predict the thermal strain under elevated temperature. The thermal stress model for CFST composite girder was derived. By the proposed model, the thermal stress was obtained from the temperature gradient curves. The results using the proposed model were agreed well with that by finite element modelling.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.922-926
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• 2006

A genetic polymorphism study on butyrophilin gene was carried out to explore variability of this gene and to estimate effects of such variability on milk quality traits in crossbred cattle. Polymorphism was unraveled by conducting Hae III PCR-RFLP of this gene. Three genotypes such as AA, BB and AB and two alleles namely A and B were observed in crossbred population. The frequencies of genotypes and alleles were 0.78, 0.17 and 0.04 for AA, AB and BB genotypes, respectively, and 0.87 and 0.13 for A and B alleles, respectively. The nucleotides, which have been substituted from allele A to B, were observed as C to G ($71^{st}$ nucleotide), C to T ($86^{th}$ nucleotide), A to T ($217^{th}$ nucleotide), G to A ($258^{th}$ nucleotide), A to C ($371^{st}$ nucleotide) and C to T ($377^{th}$ nucleotide). The nucleotide substitutions at $71^{st}$, $86^{th}$ and $377^{th}$ position of the fragment were found as silent mutations whereas nucleotide changes at $217^{th}$, $258^{th}$ and $371^{st}$ positions were detected as substitution of amino acid lysine with arginine, valine with isoleucine, and leucine with proline from allele A to B. The genotypes had significant effects ($p{\leq}0.05$) on total milk solid%, fat%, SNF%, while showing nonsignificant impact on total protein%. AA genotype produced highest average yield for all the traits.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.10
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• pp.1261-1267
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• 2010

Milk production traits are important economic traits for dairy cattle. The aim of the present study was to refine the position of previously detected quantitative trait loci (QTL) on bovine chromosome 6 affecting milk production traits in Chinese Holstein dairy cattle. A daughter design with 918 daughters from 8 elite sire families and 14 markers spanning the previously identified QTL region were used in the analysis. We employed a combined linkage and linkage disequilibrium analysis (LDLA) approach with two options for calculating the IBD probabilities, one was based on haplotypes of all 14 markers (named Method 1) and the other based on haplotypes with sliding windows of 5 markers (named Method 2). For milk fat yield, the two methods revealed a highly significant QTL located within a 6.5 cM interval (Method 1) and a 4.0 cM interval (Method 2), respectively. For milk protein yield, a highly significant QTL was detected within a 3.0 cM interval (Method 1) or a 2.5 cM interval (Method 2). These results confirmed the findings of our previous study and other studies, and greatly narrowed down the QTL positions.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.11
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• pp.1507-1510
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• 2012

Quantitative trait loci (QTL) associated with fat deposition traits in pigs are important gene positions in a chromosome that influence meat quality of pork. For QTL study, a three generation resource population was constructed from a cross between Korean native boars and Landrace sows. A total of 240 F2 animals from intercross of F1 were produced. 80 microsatellite markers covering chromosomes 1 to 10 were selected to genotype the resource population. Intervals between adjacent markers were approximately 19 cM. Linkage analysis was performed using CRIMAP software version 2.4 with a FIXED option to obtain the map distances. For QTL analysis, the public web-based software, QTL express (http://www.qtl.cap.ed.ac.uk) was used. Two significant and two suggestive QTL were identified on SSC 6, 7, and 8 as affecting body fat and IMF traits. For QTL affecting IMF, the most significant association was detected between marker sw71 and sw1881 on SSC 6, and a suggestive QTL was identified between sw268 and sw205 on SSC8. These QTL accounted for 26.58% and 12.31% of the phenotypic variance, respectively. A significant QTL affecting IMF was detected at position 105 cM between markers sw71 and sw1881 on SSC 6.

• BMB Reports
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• v.34 no.5
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• pp.402-407
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• 2001

Based on the currently proposed toxicity model for the different Bacillus thuringiensis Cry $\delta$-endotoxins, their pore-forming activity involves the insertion of the ${\alpha}4-{\alpha}5$ helical hairpin into the membrane of the target midgut epithelial cell. In this study, a number of polar or charged residues in helix 4 within domain I of the 65-kDa dipteranactive Cry11A toxin, Lys-123, Tyr-125, Asn-128, Ser-130, Gln-135, Arg-136, Gln-139 and Glu-141, were initially substituted with alanine by using PCR-based directed mutagenesis. All mutant toxins were expressed as cytoplasmic inclusions in Escherichia coli upon induction with IPTG. Similar to the wild-type protoxin inclusion, the solubility of each mutant inclusion in the carbonate buffer, pH 9.0, was relatively low When E. coli cells, expressing each of the mutant proteins, were tested for toxicity against Aedes aegypti mosquito-larvae, toxicity was completely abolished for the alanine substitution of arginine at position 136. However, mutations at the other positions still retained a high level of larvicidal activity Interestingly, further analysis of this critical arginine residue by specific mutagenesis showed that conversions of arginine-136 to aspartate, glutamine, or even to the most conserved residue lysine, also abolished the wild-type activity The results of this study revealed an important determinant in toxin function for the positively charged side chain of arginine-136 in helix 4 of the Cry11A toxin.