• Title/Summary/Keyword: Efficiency Effect

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Effect of an emitting-layer height on a photon extraction efficiency in LED (LED에서 발광층의 높이가 광추출 효율에 미치는 영향)

  • Kwon, Keeyoung
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.1
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    • pp.564-569
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    • 2021
  • In this paper, for the typical LED and the tilted LED, when there is no electrode, when 20% absorption (80% reflection) occurs at the electrode, and when 60% absorption (40% reflection) occurs at the electrode, the effect of the absorption at the electrode and the height of the active region on the photon extraction efficiency and the mean photon path length was investigated, and an appropriate height of the active region was proposed. In a typical LED, as the absorption of the electrode increases, the photon extraction efficiency decreases from 18% to 15% and 13%, and the photon extraction efficiency is highest when the height of the active area is located in the center between the two electrodes. In the tilted LED, as the absorption of the electrode increases, the photon extraction efficiency decreases from 38% to 33% and 25%, and the photon extraction efficiency is highest when the height of the active area is located in the center between the two electrodes. The tilted LED can increase the photon extraction efficiency more than twice than that of a typical LED, where photons are trapped inside the chip due to total reflection.

A Study on Determining Trade Terms for Logistics Efficiency in the Era of Logistics 4.0: Moderated Mediating Effect of Added Value of Traded Goods

  • Chang-Bong Kim;Kyeong-Wook Jeong;Hwa-Jung Hyun
    • Journal of Korea Trade
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    • v.27 no.4
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    • pp.1-18
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    • 2023
  • Purpose - The purpose of this paper is to study how flexibility and mutuality in determining trade terms impact logistics efficiency in the context of relational theory. Additionally, the effect of relational contracts on logistical efficiency relative to the value of the goods being traded is investigated. Design/methodology - According to the relational contract theory, we developed 17 factors utilizing a 7-point Likert scale to measure variables related to flexibility, mutuality, logistics efficiency, and the added value of goods. The survey occurred over four months, and was distributed directly, and via email, phone, and online Google surveys. A total of 403 surveys were collected out of 1,800 distributed, and 380 were analyzed. The principal respondents were import/export companies and members of the Korea International Trade Association and the Korea Small and Medium Business Export-Import Association. The collected data were analyzed using frequency analysis, exploratory factor analysis, and correlation analysis using SPSS ver. 26.0 statistical software, and hypothesis test results were derived using Process Macro ver. 3.5. Findings - This study provides evidence that negotiation flexibility for trade terms affects the efficiency of the logistics process, and the mutuality of such arrangements is shown to be associated with the flexibility and efficiency of logistics processes. Additionally, it has been established that companies whose trade goods possess a low degree of added value may experience increased efficiency in logistics operations if they agree to trade terms that are both flexible and mutually beneficial with their counterparts. Originality/value - This study suggests that in an environment of rapidly shifting global logistics and unpredictable related costs, trade companies may be able to improve logistics efficiency by establishing flexible, mutually beneficial trade terms when entering into contracts. Furthermore, it is suggested that companies dealing in low-value-added products may improve the logistical performance of approaching trade from a perspective of relational contracts.

NUMERICAL STUDY ON THE CLOCKING EFFECT IN A 1.5 STAGE AXIAL TURBINE (1.5단 축류터빈에서의 Clocking 효과에 관한 수치적 연구)

  • Park, Jong-Il;Choi, Min-Suk;Baek, Je-Hyun
    • Journal of computational fluids engineering
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    • v.11 no.4 s.35
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    • pp.1-8
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    • 2006
  • Clocking effects of a stator on the performance and internal flow in an UTRC 1.5 stage axial turbine are investigated using a three-dimensional unsteady flow simulation. Six relative positions of two rows of stator are investigated by positioning the second stator being clocked in a step of 1/6 pitch. The relative efficiency benefit of about 1% is obtained depending on the clocking positions. However, internal flows have some different characteristics from that in the previous study at the best and worst efficiency positions, since the first stator wake is mixed out with the rotor wake before arriving at the leading edge of the second stator. Instead of the first stator wake, it is found that the wake interaction of the first stator and rotor has a important role on a relative efficiency variation at each clocking position. The time-averaged local efficiency along the span at the maximum efficiency is more uniform than that at the minimum efficiency. That is, the spanwise efficiency distribution at the minimum efficiency has larger values in mid-span but smaller values near the hub and casing in comparison to those at the maximum efficiency. Moreover, the difference between maximum and minimum instantaneous efficiencies during one period is found to be smaller at the maximum efficiency than at the minimum efficiency.

Numerical Study on the Clocking Effect in a 1.5 Stage Axial Turbine (1.5단 축류 터빈에서의 Clocking 효과에 관한 수치적 연구)

  • Park, Jong-Il;Choi, Min-Suk;Baek, Je-Hyun
    • 유체기계공업학회:학술대회논문집
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    • 2005.12a
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    • pp.473-480
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    • 2005
  • Clocking effects of a stator on the performance and internal flow in an UTRC 1.5 stage axial turbine are investigated using a three-dimensional unsteady flow simulation. Six relative positions of two rows of stator are investigated by positioning the second stator being clocked in a step of 1/6 pitch. The relative efficiency benefit of about 1% is obtained depending on the clocking positions. However, internal flows have some different characteristics from that in the previous study at the best and worst efficiency positions, since be first stator wake is mixed out with the rotor wake before arriving at the leading edge of the second stator. Instead of the first stator wake, it is found that the wake interaction of the first stator and rotor has a important role on a relative efficiency variation at each clocking position. The time-averaged local efficiency along the span at the maximum efficiency is more uniform than that at the minimum efficiency. That is, the spanwise efficiency distribution at the minimum efficiency has larger values in mid-span but smaller values near the hub and casing in comparison to those at the maximum efficiency. Moreover, the difference between maximum and minimum instantaneous efficiencies during one period is found to be smaller at the maximum efficiency than at the minimum efficiency.

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A Study on the Characteristics of Global FDI on China's Balanced Development Strategy : Focusing on Korean FDI Characteristics by Major Cities in China (중국지역균형발전전략에 미치는 글로벌 FDI 특성에 관한 연구 :중국주요도시별 한국FDI 특성을 중심으로)

  • Ryoo, Sung-Woo;Mun, Cheol-Ju
    • Korea Trade Review
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    • v.43 no.4
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    • pp.155-175
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    • 2018
  • This study estimates the technical efficiency and total factor productivity(TFP) of and analyzes the relationship between TFP and exports for Korean manufacturing companies from 2000 to 2016. Specially, TFP is decomposed into Technical Change(TC), Technical Efficiency Change (TEC), and Sale Effect(SE), and compared between large and small enterprises. First, in the case of technical efficiency, the Korean economy has been very vulnerable to external shocks, such as the sharp decline following the 2008 financial crisis. The efficiency of the electronics, automobile, and machinery sectors is low and needs to be improved. In addition, the technological efficiency of large enterprises is higher than that of SMEs in most manufacturing sub-sectors except for non-ferrous metals. In the case of TFP, most changes are due to TC, and the effective combination of labor, capital and the effect of scale have little effect, suggesting that improvement of internal structure is urgent. In addition, volatility due to the impact of the financial crisis in 2008 was much larger in SMEs than in large companies, so external economic impacts are more greater for SMEs than large enterprises. The relationship between TFP decomposition factors and exports shows that TC has a positive effect only on exports of SMEs. Therefore, in order to increase exports, in the case of SMEs, R&D support to promote technological development is needed. In the case of large companies, it is necessary to establish differentiated strategies for each export market, competitor company, and item to link efficiency and scale effect of exports.

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The Analysis on Energy Efficiency in the Residential Sector (가정부문 에너지 효율 분석)

  • Na, In-Gang;Lee, Sung-Keun
    • Environmental and Resource Economics Review
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    • v.19 no.1
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    • pp.129-157
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    • 2010
  • This paper is intended to evaluate energy efficiency policy in demand side, to assess the residential sector's energy efficiency policy and to analyze the system of energy efficiency practices. We examined residential energy consumption over the period 1990~2006. The decomposition method in the analysis was a logarithmic mean Divisia index (LMDI) techniques to decompose changes in energy intensity. First of all, the energy use in residential sector was adjusted to correct weather-induced variations in energy consumption, because adjustments for normal weather patterns facilitated inter-temporal comparison of intensity. The analysis on the residential sector shows that the overall energy intensity of the residential sector declined at an average 1.0% per year, while the structure effect increased by 1.8% per year, and the activity effect increased by 0.7% per year. In other words, the decline of floor space, number of household, and appliance ownership per capita has an effect on increase in residential consumption. The improvement in energy efficiency had strong contribution on the decrease of energy consumption. We find that the general results of analysis on residential energy are similar to those of IEA. The energy efficiency policy in residential sector is assessed to obtain some results during 1990~2006. In residential sector, structural variables such population per household, diffusion of appliance and activity factor such as population contributed to the increase of energy consumption while energy intensity effect induced the decrease of energy consumption. These findings are consistent with international trend as well as our prior expectation.

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A Study on the Optimal Conditions of the Biogas Sorting by Using the Polysulfone Membrane (다공성 분리막을 이용한 최적의 Bio-gas 분리인자 도출)

  • Lee, Seung-Won;Jeong, Chang-Hoon;Kim, Jung-Kwon
    • Journal of Environmental Science International
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    • v.20 no.8
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    • pp.1011-1019
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    • 2011
  • The objective of this research is to evaluate optimal conditions of permeability and selectivity on the polysulfone membrane for efficiency of separation of $CH_4$ by checking four factors which are temperature, pressure, gas compositions and gas flow rates. When higher pressure was applied at the input, lower efficiency of recovery of $CH_4$ and higher efficiency of separation of $CH_4$ were shown. It has the tendency to show lower efficiency of recovery of $CH_4$ and higher efficiency of separation of $CH_4$ at the output as higher temperature at input. The lower flow rates make higher efficiency of recovery of $CH_4$ and lower efficiency of separation of $CH_4$. Finally, over 90% efficiency for $CH_4$ separation and recovery conditions are temperature ($-5^{\circ}C$), pressure (8 bar), gas composition rate (6:4) ($CH_4:CO_2$) and gas flow rate ($5\ell$/min). These conditions make higher separation and recovery efficiency such as 90.1% and 92.1%, respectively.

Analysis of Bank Efficiency Between Conventional Banks and Regional Development Banks in Indonesia

  • ABIDIN, Zaenal;PRABANTARIKSO, R.Mahelan;WARDHANI, Rhisya Ayu;ENDRI, Endri
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.1
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    • pp.741-750
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    • 2021
  • The research aims to analyze the level of efficiency by grouping banks during the period 2017 - 2018 into category 1 and category 2 banks and then dividing them as Regional Development Banks (BPD) and Non-BPD Conventional Commercial Banks (BUK) within each category. The research objects are banks within the categories BPD and BUK comprised 18 BPDs and 35 BUKs. The research methodology uses 3 stages, first, using Data Envelopment Analysis (DEA) we measure the level of bank efficiency; second, using the Tobit regression model we evaluate the effect of financial performance on DEA efficiency, and third, using the Mann-Whitney test we determine whether there is a difference in the efficiency of category 1 and 2 banks. The results showed that there was a decrease in the efficiency of category 1 and 2 banks but on average, the efficiency of category 1 banks is higher than category 2 banks. The estimation results of the Tobit regression model show that only the ROA variable affects the efficiency level of category 1 banks, while category 2 banks are influenced by NPL and ROA variables. In the Mann-Whitney test, it was proven that there were differences in efficiency between BUK and BPD in category 1 and 2 banks.

Evaluation of Information Technology Impact on State-owned Commercial Banks' Efficiency: The Case of Bangladesh

  • BEGUM, Shakera;BATEN, Md. Azizul;ALI, Rahmat
    • Asian Journal of Business Environment
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    • v.12 no.1
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    • pp.1-9
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    • 2022
  • Purpose: This study measures the effect of Information Technology (IT) on both cost and profit efficiency of State-owned Commercial Banks (SOCBs) in Bangladesh. Research design, data and methodology: Yearly Non-IT and IT data are collected from the annual report of SOCBs of Bangladesh from 2008 to 2017. Variable Return to Scale (VRS) cost Data Envelopment Analysis (DEA) and Profit DEA are employed to measure the efficiency of SOCBs and Ordinary Least Square (OLS) is used to investigate the impacts of ICT components on operating cost and profit efficiency for SOCBs. Results: The average cost efficiency (74.4%) was noticed higher than the average profit efficiency (20.6%) for SOCBs. SOCBs were more affordable and less profitable for both cost and profit efficiency. Rupali bank was the most cost efficient while Sonali bank was the most profit efficient. IT Investment and IT personnel expenses were positively significant for cost efficiency. IT income, IT personnel, IT personnel expenses, ATM expenses, and Credit card expenses were negatively significant for profit efficiency. Conclusion: The further studies can combine DEA with machine learning algorithms to study the impact of IT on banks' performances. The results could aid government to remove the hindrance of progress in Bangladesh.

Influence of Kaolinite Clay Supplementation on Growth Performance and Digestive Function in Finishing Calf-fed Holstein Steers

  • Ortiz, Jose;Montano, Martin;Plascencia, Alejandro;Salinas, Jaime;Torrentera, Noemi;Zinn, Richard A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.11
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    • pp.1569-1575
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    • 2016
  • Two experiments were conducted to examine the influence of kaolinite clay supplementation (0%, 1%, or 2% diet dry matter [DM] basis) on characteristics of digestion (Trial 1) and growth performance (Trial 2) in calf-fed Holstein steers fed a finishing diet. In Trial 1, 6 Holstein steers ($539{\pm}15kg$) with ruminal and duodenal cannulas were used to evaluate treatment effects on characteristics of digestion. Kaolinite clay supplementation decreased total tract DM digestion (linear effect, p<0.01) without effects ($p{\geq}0.10$) on site and extent of digestion of organic matter, neutral detergent fiber, starch and N, or ruminal microbial efficiency. There were no treatment effects on ruminal pH, volatile fatty acids molar proportions or estimated methane production. In Trial 2, 108 Holstein steers ($132.4{\pm}5.6kg$) were used in a 308-d study to evaluate growth performance and carcass characteristics. There were no treatment effects (p>0.10) on average daily gain (ADG) and gain efficiency (ADG/dry matter intake). Kaolinite supplementation tended (linear effect, p = 0.08) to increase dietary net energy (NE) during the initial 112-d period. However, the overall (308-d) effect of supplementation dietary NE was not appreciable (p>0.20). However, due to the inertness of kaolinite, itself, the ratio of observed-to-expected dietary NE increased with kaolinite supplementation. This effect was more pronounced (linear effect, $p{\leq}0.03$) during the initial 224 d of the study. Overall (308 d), kaolinite supplementation tended to increase (linear effect, p = 0.07) dietary NE by 3% over expected. Kaolinite supplementation did not affect carcass weight, yield grade, longissimus area, kidney, pelvic and heart fat, and quality grade, but decreased (linear effect, p = 0.01) dressing percentage. It is concluded that kaolinite supplementation up to 2% of diet DM may enhance energetic efficiency of calf-fed Holstein steers in a manner independent of changes in characteristics of ruminal and total tract digestion.