• Journal of Korean Elementary Science Education
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• v.36 no.3
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• pp.219-226
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• 2017

In this study, the reliability and validity of the retrospective pre-post test were analyzed in order to solve the problem of traditional pre-post test including response shift bias. Samples of the study were 162 elementary school students who are studying at the S university gifted education center in Seoul. Before completion of the field trip, we conducted pre test of science-related attitudes. After completion of the field trip, respondents were asked to compare their responses of pre and post science-related attitudes to quantitatively analyze the commonalities and differences of the two tests. To find out more characteristics, qualitative data such as daily records and interview were also gathered and analyzed. The major results of the study are as follows. First, for the paired t-test, there was no statistically significant difference between separate pre-test scores and retrospective pre-test. There was a very high correlation between the separate pre-test scores and the retrospective pre-test. Second, there were significant differences in all seven sub-factors of science-related attitudes between the retrospective pre-test and the post-test. Third, the separate pre-test scores showed a slightly higher tendency than the retrospective pre-test scores. This suggests that the response shift bias appears when it is performed the separate pre-test in affective domain. As a result of the interview, it was found that the evaluation standards of separate pre-test did not match with those of post-test. Forth, internal consistency reliability of the retrospective pre-test was higher than that of the separate pre-test. However, there were significant differences in six factors of science-related attitudes excluding the 'social implications of science' between the separate pre-test and the post-test. Based on these results, the retrospective pre-post test design provides simplicity and convenience to both respondents and investigators, as it is done with one test. The retrospective pre-post test design can be regarded as a valid design for the self-report measurement of affective domain on a single experimental group.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.4
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• pp.1-10
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• 2011

Beating or refining is an energy intensive process in paper industry. In India, most of the paper industries blend long fibered softwood pulps with short fibered hardwood or agro based pulps to get the paper properties of competitive level. Refining characteristics of the blend of pulps is very crucial with respect to freeness and strength properties. This study has been carried out to understand the refining behavior of three hardwood pulps and a softwood pulp. The hardwood and softwood pulps are blended in different proportions in two different ways; a) blending after their separate refining, and b) blending before refining followed by mixed refining of the blended pulps. Freeness of pulp, strength, optical and surface properties of paper along with formation have been determined and compared for both the refining methods. The fiber classification of refined pulps was also carried out to analyze the effect of refining method on fiber morphology. The mixed refining of hardwood and softwood pulps marginally affects the fiber morphology in comparison to separate refining of pulps. The strength and other properties of paper prepared from mixed refining of pulps are either better or comparable than those of separately refined pulps.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.4
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• pp.89-94
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• 2008

Differential pressure flow meters which have a shape of triangular separate bar(TSB) were tested for investigating the flow rate characteristics of the flow meters with varying the temperature of the gas flow. Three kinds of the triangular separate bar flow meters whose aerodynamic angles are different one another are used. The mass flow rate of the flow meters are evaluated using a non-dimensional parameter which includes the gas temperature, exhaust gas pressure and differential pressure at the flow meters, and atmospheric pressure. A burner system which is similar to gas turbine was used for raising the gas flow temperature. The burner system was operated with varying the air/fuel ratio by controlling both the fuel injection rate from the fuel nozzle and air flow rate from a blower. An empirical correlation between the mass flow rate at the TSB flow meter and the non-dimensional parameter was obtained. The empirical correlation showed linear relationship between the mass flow rate and the non-dimensional parameter H. Also, the mass flow rate characteristics at the TSB flow meter was affected by the gas temperature.

• Structural Engineering and Mechanics
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• v.85 no.1
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• pp.119-133
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• 2023

Impact event is the key factor influencing the operational state of the mechanical equipment. Additionally, nonlinear factors existing in the complex mechanical equipment which are currently attracting more and more attention. Therefore, this paper proposes a novel hybrid-separate identification strategy to solve the force identification problem of the nonlinear structure under impact excitation. The 'hybrid' means that the identification strategy contains both l1-norm (sparse) and l2-norm regularization methods. The 'separate' means that the nonlinear response part only generated by nonlinear force needs to be separated from measured response. First, the state-of-the-art two-step iterative shrinkage/thresholding (TwIST) algorithm and sparse representation with the cubic B-spline function are developed to solve established normalized sparse regularization model to identify the accurate impact force and accurate peak value of the nonlinear force. Then, the identified impact force is substituted into the nonlinear response separation equation to obtain the nonlinear response part. Finally, a reduced transfer equation is established and solved by the classical Tikhonove regularization method to obtain the wave profile (variation trend) of the nonlinear force. Numerical and experimental identification results demonstrate that the novel hybrid-separate strategy can accurately and efficiently obtain the nonlinear force and impact force for the nonlinear structure.

• Fire Science and Engineering
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• v.27 no.6
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• pp.97-103
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• 2013

This study analyzes the present public construction ordering system focussing on the legal framework for the fire facilities construction business and investigates the problem of subcontracting, and further reviews why Separate Prime Contracting should be recommended in policy, social, legislative and regulative terms. This study suggests the amendment of Fire Facilities Construction Business Act, with new bill drafting. The result of this study shows the present public construction ordering system has huge disparities between main building construction business and fire facilities construction business, and recommend Separate Prime Contracting should be adopted in the fields of fire facilities construction business. The system of Separate Prime Contracting may secure business entities' responsibility and higher quality of fire facilities, and also result in reasonable construction practices in reasonable costs. This system may also contribute to improve public safety level in fire facilities construction.

• Journal of the Korea Organic Resources Recycling Association
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• v.6 no.2
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• pp.113-129
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• 1998

To suggest the separate collection system of garbage in household, people's disposition was evaluated. It was indicated that garbage be collected daily to minimize the odor which was major nuisance from garbage. However, most people wanted to discharge garbage in two or three days interval, as they did not prefer frequent handling. So, proper size of garbage container was determined as two to three days capacity. In contrast with it, it was major opinion that dicharged garbage should be collected everyday by local government to eliminate the outdoor pollution. Plastic bag was the most popular container, as it could be used instantly. Price of the bag affected on the efficiency of reduction and separate collection of garbage. Low price increased the separate collection and decreased the reduction, while high price introduced the opposite result. So, the dual price system was suggested to enhance both objectives.

• Restorative Dentistry and Endodontics
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• v.43 no.3
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• pp.33.1-33.8
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• 2018

Objectives: This study aimed to investigate the prevalence of a separate distolingual root and to measure the thickness of the buccal cortical bone in mandibular first molars in Koreans using cone-beam computed tomography (CBCT) images. Materials and Methods: High-quality CBCT data from 432 patients were analyzed in this study. The prevalence of a separate distolingual root of the mandibular first molar was investigated. The distance from the distobuccal and distolingual root apices to the outer surface of the buccal cortical bone was measured. We also evaluated the thickness of the buccal cortical bone. Results: The prevalence of a separate distolingual root (2 separate distal roots with 1 canal in each root; 2R2C) was 23.26%. In mandibular first molars with 2R2C, the distance from the distobuccal root apex to the outer surface of the buccal cortical bone was 5.51 mm. Furthermore, the distance from the distolingual root apex to the outer surface of the buccal cortical bone was 12.09 mm. In mandibular first molars with 2R2C morphology, the thickness of the buccal cortical bone at the distobuccal root apex of the mandibular first molar was 3.30 mm. The buccal cortical bone at the distobuccal root apex was significantly thicker in the right side (3.38 mm) than the left side (3.09 mm) (p < 0.05). Conclusions: A separate distolingual root is not rare in mandibular first molars in the Korean population. Anatomic and morphologic knowledge of the mandibular first molar can be useful in treatment planning, including surgical endodontic treatment.

• Journal of the Korean Dietetic Association
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• v.15 no.4
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• pp.397-404
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• 2009

In this study, we examined food intake, sodium intake, and satiety rate for different methods of consuming soup. Healthy young women (n=50) participated in this study. The subjects ate cooked rice and soup using a method that they preferred and then they were assigned into separate intake groups based on how they consumed their rice and soup. One group consisted of women that ate their soup and cooked rice separately (separate intake group, n=30). The second group consisted of the women who mixed the rice and the soup prior to consumption (mixed intake group, n=20). The mixed intake group consumed significantly more food (p<0.001) and sodium (p<0.05) than the separate intake group. Because of the high water content and ease of swallowing for the mixed intake method, the eating rate of the mixed intake group (42.5 g/min) was significantly higher than that of the separate intake group (28.8 g/min) (p<0.01). However, despite consuming 79.5 g more food at lunch, the rates of satiety were not significantly different before and after eating between the mixed intake and separate intake group. Therefore, eating rate, consumption norms and concept of "clean one's bowl" may influence food intake and sodium intake. Although more studies are needed, these data suggest eating cooked rice and soup separately may help to control obesity and hypertension.

• BMB Reports
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• v.41 no.11
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• pp.814-819
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• 2008

Interleukin-32 (IL-32) induces a variety of proinflammatory cytokines and chemokines. The IL-32 transcript was reported originally in activated T cells; subsequently, it was demonstrated to be abundantly expressed in epithelial and endothelial cells upon stimulation with inflammatory cytokines. IL-32 is regulated robustly by other major proinflammatory cytokines, thereby suggesting that IL-32 is crucial to inflammation and immune responses. Recently, an IL-32$\alpha$-affinity column was employed in order to isolate an IL-32 binding protein, neutrophil proteinase 3 (PR3). Proteinase 3 processes a variety of inflammatory cytokines, including TNF$\alpha$, IL-$1{\beta}$, IL-8, and IL-32, thereby enhancing their biological activities. In the current study, we designed four PR3-cleaved IL-32 separate domains, identified by potential PR3 cleavage sites in the IL-32$\alpha$ and $\gamma$ polypeptides. The separate domains of the IL-32 isoforms $\alpha$ and $\gamma$ were more active than the intrinsic $\alpha$ and $\gamma$ isoforms. Interestingly, the N-terminal IL-32 isoform $\gamma$ separate domain evidenced the highest levels of biological activity among the IL-32 separate domains.

• Journal of IKEEE
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• v.16 no.4
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• pp.283-289
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• 2012

In this paper, We proposed Separate Gate Technique(SGT) to improve the switching characteristics of Trench power MOSFET. Low gate-to-drain 전하 (Miller 전하 : Qgd) has to be achieved to improve the switching characteristics of Trench power MOSFET. A thin poly-silicon deposition is processed to form side wall which is used as gate and thus, it has thinner gate compared to the gate of conventional Trench MOSFET. The reduction of the overlapped area between the gate and the drain decreases the overlapped charge, and the performance of the proposed device is compared to the conventional Trench MOSFET using Silvaco T-CAD. Ciss(input capacitance : Cgs+Cgd), Coss(output capacitance : Cgd+Cds) and Crss(reverse recovery capacitance : Cgd) are reduced to 14.3%, 23% and 30% respectively. To confirm the reduction effect of capacitance, the characteristics of inverter circuit is comprised. Consequently, the reverse recovery time is reduced by 28%. The proposed device can be fabricated with convetional processes without any electrical property degradation compare to conventional device.