• Title/Summary/Keyword: Cross-National Effect

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Shape Effect of Inlet Nozzle and Draft Tube on the Performance and Internal Flow of Cross-Flow Hydro Turbine

  • Choi, Young-Do;Son, Sung-Woo
    • Journal of Advanced Marine Engineering and Technology
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    • v.36 no.3
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    • pp.351-357
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    • 2012
  • Small hydropower is a reliable energy technology to be considered for providing clean electricity generation. Producing electrical energy by small hydropower is the most efficient contribution to renewable energy. Cross-flow turbine is adopted primarily because of its simple structure and high possibility of applying to small hydropower. The purpose of this study is to investigate the effect of inlet nozzle shape on the performance and internal flow of a cross-flow turbine for small hydropower by CFD analysis. Moreover, the shape effect of draft tube has been investigated according to modified shapes of the length and the diffuse angle. The results show that relatively narrow and converging inlet nozzle shape gives better effect on the performance of the turbine.

A study on the effect of cross magnetization to the generator parameters and simplified linear model (교차자화 포화효과에 의한 발전기 정수와 간략모델에 미치는 영향에 관한 연구)

  • Kim, Deok-Young;Kwon, Sae-Hyuk
    • Proceedings of the KIEE Conference
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    • 1999.07c
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    • pp.1236-1238
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    • 1999
  • This paper presents an effect of cross magnetization to the generator simplified linear model which is used for multi-machine power systems. The formulae of reactances and time constant with saturation effect are presented. The simulation results show that cross magnetization has an effect which can not be ignored, to the reactances, time constant and eigenvalues in one machine infinite bus system of simplified linear model.

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The Effect of Cross-Model's Product Demonstration and Product Involvement on Attitudes toward the Ad

  • Taemin Kim
    • International Journal of Internet, Broadcasting and Communication
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    • v.15 no.2
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    • pp.254-260
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    • 2023
  • Recently, the cross-model strategy of using male models in advertisements for women's cosmetics has been increasingly utilized. Academics have begun to discuss and study cross-model advertisements, but most of the studies have focused on the effects of the presence of a cross model. We investigated the effects of a crossmodel's product demonstration as an advertising creative strategy on consumer's attitudes toward the ad. We examined the effects of a male model demonstrating the advertised products for women's cosmetics on female consumers' attitudes toward the ad. As a result, we found that when a male model demonstrated a product in a women's product advertisement, consumers' attitudes toward the ad were more positive the higher their product involvement. Therefore, product involvement was found to be a moderating variable in the effect of cross-model product demonstration on attitudes toward the ad. This study contributes to the line of research on the effect of cross-model and product demonstration advertising, providing practical implications for advertising practitioners.

Effect of Air Layer on the Performance of an Open Ducted Cross Flow Turbine

  • Wei, Qingsheng;Chen, Zhenmu;Singh, Patrick Mark;Choi, Young-Do
    • The KSFM Journal of Fluid Machinery
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    • v.18 no.1
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    • pp.11-19
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    • 2015
  • Recently, the cross flow turbines attract more attention for their good performance over a large operating regime at off design point. This study employs a very low head cross flow turbine, which has open inlet duct and has barely been studied before, to investigate the performance of the cross flow turbine with air suction from the rear part of the runner. Unlike conventional cross flow turbines, a draft tube is attached to the outlet of runner to improve the turbine performance. Water level and pressure in the draft tube are monitored to investigate the influence of air suction. Torque at local blade passage of three parts of runner is examined in detail under the conditions of different air suction. Consequently, it is found that with proper air suction in the runner chamber, the water level in the draft tube gradually drops to Stage 2 of the runner and the efficiency of the turbine can be raised by 10%. Overall, the effect of air-layer on the performance of the turbine is considerable.

Analysis of cross magnetizing effect on the generator characteristics (발전기 특성에 미치는 교차자화 포화현상의 영향 해석)

  • Kim, Deok-Young;Rho, Kyu-Min;Kwon, Sae-Hyuk
    • Proceedings of the KIEE Conference
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    • 1998.07c
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    • pp.1224-1227
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    • 1998
  • This paper presents an effect of cross magnetization to the generator characteristics in synchronous machine infinite bus system. Eigenvalues, synchronous torque and damping torque are investigated as the operating condition of the system is changed variously. The simulation results show that cross magnetization has an important effect to the generator characteristics in steady state stability analysis.

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Shear Performance of PUR Adhesive in Cross Laminating of Red Pine

  • Kim, Hyung-Kun;Oh, Jung-Kwon;Jeong, Gi-Young;Yeo, Hwan-Myeong;Lee, Jun-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.41 no.2
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    • pp.158-163
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    • 2013
  • Cross laminated timber (CLT) has been an rising issue as a promising building material replacing steel-concrete in mid story rise construction. But, there was no specific standard for CLT because it had been developed in industrial section. Recently, new draft for requirements of CLT was proposed by EN which suggested to evaluate the performance of adhesive in CLT by the same method as glulam. But, it has been reported that shear performance of cross laminated timber is governed by rolling shear. Therefore, block shear tests were carried out to compare parallel to grain laminating and cross laminating using commercial one component PUR (Poly urethane resin). The result showed that the current glulam standard for evaluating bonding performance is not appropriate for CLT. Beacause shear strength of cross laminating decreased to 1/3 of parallel to grain laminating and this strength was representing shear performance of wood itself not the bond. However, cross laminating showed no significant effect on wood failure. Thus, wood failure can be used as a requirement of CLT bonding. Based on the results, cross laminating effect should be included when evaluating adhesive performance of CLT correctly and should be considered as an important factor.

Study on Utilization of Heterosis in Layer Chicken (산란계종의 잡잡강세리용에 관한 연구)

  • 오봉국;여정수;이정구;이문연
    • Korean Journal of Poultry Science
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    • v.7 no.2
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    • pp.28-36
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    • 1980
  • This study was carried out to estimate combining abilitie or economic traits in layer chickens. The data used in this study were the record of 10 single crosses produced by half diallel cross of 5 lines of Single Comb White Leghorns, such as A, B, C, K and S lines. Total 720 progenies of the crosses were reared at the Poultry Breeding Farm, College of Agriculture, Seoul National University from Feb. 1979 to August, 1980. Combining abilities were estimated by Grilling's mathematical model for the traits; age the first egg, total egg number, egg weight and body weight. The results attained from the studies were summarized as follows; In estimate of combining ability, an age at first egg of BS cross was largely due to significiantly higher general combining ability (G. C. A.) effect of B and S strains than Cand K strains in G. C. A. effect, and to specific combining ability (S. C. A) effect of B and S-trains. AB and BS crosses showed the highest egg Production. AB cross performance was result from high G.C.A. effect of A ana B strains. BS cross performance was result from high G. C. A. effect of B and high S. C. A. effect of BS cross. Specific combining ability effect in egg. weight was not statiscally significiant, but S strain showed high G. C. A. effect. A and B strains in body weight showed significantly low C. C. A. effect. From the above results, BS cross in an age at first egg, AB and BS crosses in egg Production, S strain in egg weight and AB cross in body weight were superior to other strains or crosses.

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Plasmonic Color Filter with Robustness Against Cross Talk for Compact Imaging Applications

  • Cho, Hyo Jong;Do, Yun Seon
    • Current Optics and Photonics
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    • v.4 no.1
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    • pp.16-22
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    • 2020
  • In high resolution imaging devices, smaller aperture in the color filter causes cross talk which provides incorrect information. Plasmonic color filters (PCFs) have been reported as an alternative of the conventional color resist based-color filter (CRCF) and many studies on PCFs demonstrated the filtering function by PCFs with a sub-micron size. In this work, we investigated the cross talk performance of PCFs compared to CRCFs. The effect of cross talk over distance from the filter were measured for each filter. Despite poorer spectral filtering characteristics, PCFs were more robust against cross talk than CRCFs. Also, the further away from the filter, the more cross talk appeared. As a result, PCFs showed less cross talk than CRCFs at about 82% of the results measured at a distance of 2~10 ㎛. This study will help to make practical use of PCFs in high-resolution imaging applications.

A Panel Analysis on the Cross Border E-commerce Trade: Evidence from ASEAN Countries

  • HE, Yugang;WANG, Jingnan
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.2
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    • pp.95-104
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    • 2019
  • Along with the economic globalization and network generalization, this provides a good opportunity to the development of cross-border e-commerce trade. Based on this background, this paper sets ASEAN countries as an example to exploit the determinants of cross-border e-commerce trade including the export and the import, respectively. The panel data from the year of 1998 to 2016 will be employed to estimate the relationship between cross-border e-commerce trade and relevant variables under the dynamic ordinary least squares and the error correction model. The findings of this paper show that there is a long-run relationship between cross-border e-commerce trade and relevant variables. Generally speaking, the GDP(+) and real exchange rate(-export & +import) have an effect on cross-border e-commerce trade. However, the population (+) and the terms of trade (-) only have an effect on cross-border e-commerce import. The empirical evidences show that the GDP and the real exchange rate always affect the development of cross-border e-commerce trade. Therefore, all ASEAN countries should try their best to develop the economic growth and focus on the exchange rate regime so as to meet the need of cross-border e-commerce trade development.

Effect of Plasticizer and Cross-Linking Agent on the Physical Properties of Protein Films

  • Lee, Myoung-Suk;Lee, Se-Hee;Ma, Yu-Hyun;Park, Sang-Kyu;Bae, Dong-Ho;Ha, Sang-Do;Song, Kyung-Bin
    • Preventive Nutrition and Food Science
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    • v.10 no.1
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    • pp.88-91
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    • 2005
  • To improve the physical properties of protein films, various plasticizers and cross-linking agents were used in the preparation of the films. For zein film, 3% polypropylene glycol with 3% glycerol was the best plasticizer, while 2.5% glycerol was the most suitable for soy protein isolate (SPI) film in terms of tensile strength (TS), % elongation, and water vapor permeability (WVP). Formaldehyde, glutaraldehyde, glyoxal, and cinnamaldehyde as cross-linking agents of protein films were used to further improve the physical properties of the films. All aldehydes used as cross-linking agent in this study improved TS of zein and SPI films. In particular, cinnamaldehyde was the best cross-linking agent due to its safety in foods. These results suggest that appropriate use of plasticizer and cross-linking agent like cinnamaldehyde should improve the physical properties of protein films for use in food packaging.