• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.255-261
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• 2019

This trial was conducted to determine the optimal supplementation level of Hermetia illucens (HI) on the growth performance, the apparent total tract retention of nutrients and the economic efficiency in weaning pigs. A total of 192 weaned pigs ($Landrace{\times}Yorkshire{\times}Duroc$; $6.51{\pm}0.15kg$) were randomly allotted to 4 treatments and 6 replicates on the basis of their initial body weight. The dietary treatments included a corn-soybean meal based diet supplemented with 0, 1, 2 or 3% HI. There were no significantly effects between the treatments in phases I, II and overall. But average daily gain was significant and linearly increased when HI was added to the diet in the overall group. Although digestibility of dry matter (DM) was increased by adding HI, digestibility responses were not observed by supplying HI in phase I. Also, all the parameters of economic efficiency were not significantly different according to the level of HI. The results showed that HI had beneficial effects on growth performance and digestibility of dry matter. However, there were no effects on economic efficiency by using HI in weaning pig diets.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.7
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• pp.579-587
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• 2001

This study investigates particle collection characteristics of a cylindrical electrostatic precipitator. Experimental work has been made for the submicron particles. The effects of polarity of discharge electrode wire, particle diameter, gas velocity, gas temperature, and specific corona power on the particle collection efficiency are investigated. The efficiency of negative corona is higher than that of positive corona. as the particle diameter increases, the efficiency is decreased when the diameter is in the range of 0.02-0.6 micron, but is increased for the nanometer particles with diameter smaller than 0.02 micron. The efficiency is increased with increase of specific corona power. As the gas temperature increases, overall collection efficiency is increased for a negative corona, but is deceased for a positive corona.

• Korean Journal of Organic Agriculture
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• v.17 no.1
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• pp.19-33
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• 2009

This paper evaluates the technical efficiency of organic farm management practices and studies its main determinants in Hongdongmyeon of Hongsung county, Chungnam province. The analysis is performed in two stages. First, the efficiency is measured via the nonparametric "Data Envelopment Analysis" (DEA) technique. The DEA models are constructed not only to assess the overall technical efficiency of organic fanning practices but also to evaluate the management efficiencies. In a second stage critical determinants of efficiency are determined using a Tobit model. In this analysis the focus is on technical and socio-economic variables. The analytical results show that technically efficient farms is about 13 percent and the mean technical efficiency is found to be 0.73 indicating that many farms are not operating at an efficient scale.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.6
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• pp.633-640
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• 2000

The effects of structure modification of the vortex finder on the collection efficiency and pressure drop have been investigated. The pressure drop in a cyclone having the two stage vortex finder is higher than that in a conventional cyclone and increases proportionally with the increase of square of gas inlet velocity in both cases. The pressure drop of both conventional cyclone of friction resistance at the boundary layer. The collection efficiency of fine dust has been enhanced by addition of vortex finder in a conventional cyclone and gas inlet velocity showing maximum dust removal efficiency increase to 17 m/s(1.7 times of saltation velocity). Optimum size of two stage vortex finder has been induced to 13 cm I.D$\times$2.6cm Length from the results of overall dust collection efficiency. Previous models were tested for the simulation of collection efficiency of cyclone having two stage vortex finder and the Dietz model predict the similar value with experimental results of the present study.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.729-740
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• 2020

The study examines the efficiency of private sector banks in India with the help of Window DEA (Data Envelopment Analysis) for a period from 2005 to 2017. With a window of three years, the period was divided into 11 windows. The study outcomes show that 59.9% of all private sector banks in India operate at more than 0.9 level of efficiency, and there are only three occasions when banks were operating at the efficiency value between 0.6 to 0.7. Further, the consistency in the efficiency scores of the banks has also been analyzed using an efficiency mapping matrix, and the mean efficiency score of the bank in each window is studied. The score of standard deviation was interpreted accordingly for these banks. Banks that are showing the highest efficiency scores also have a higher variance of efficiency scores. There was no bank identified in the matrix that promises high-efficiency ratings with low variability. The study concludes that the analysis of the efficiency mapping matrix indicates that, as a DMU escalates in the efficiency scores, the standard deviation reflecting the risk in overall efficiency scores also tends to rise. The findings complement the concept of higher risk to higher return or greater efficiency.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.10
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• pp.1340-1347
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• 2010

To study the effects of ${\alpha}$-galactosidase (${\alpha}$-Gal) supplementation on performance and energy metabolism, 216 Arbor Acres male broilers were placed in 36 cages of 6 birds each and allotted to 4 diets for 42 d, with 0-21 d as starter period and 22-42 d as grower period. The 4 diets were based on corn non-dehulled soybean meal in a $2{\times}2$ factorial arrangement, with 2 levels of ${\alpha}$-Gal (0 vs. 60 U/kg feed) and 2 levels of ME (normal metabolizable energy (NME) and low metabolizable energy (LME)). Bird performance was obtained at 21 and 42 d of age with samples of feces collected for nutrient digestibility from 19-21 d and 40-42 d. At 21 and 42 d, 1 bird from 6 cages of each treatment was killed to determine liver weight, intestinal pH and chyme viscosity. With the addition of ${\alpha}$-Gal the 42 d body weight (BW) and 0-42 d average daily gain (ADG) were significantly improved (p<0.05). Average daily feed intake (ADFI) of birds fed the LME diet was significantly increased compared to those fed the NME diet during starter (p<0.01) and grower (p<0.05) periods and overall (p<0.01). There was an interaction of ${\alpha}-Gal{\times}ME$ on 0-21 d ADFI (p<0.01). Supplementation of ${\alpha}$-Gal significantly improved (p<0.01) feed efficiency during the grower period and overall. Feed efficiency of birds fed the LME diet was significantly decreased (p<0.05) compared to those fed the NME diet during the starter period and overall. With the addition of ${\alpha}$-Gal apparent metabolizable energy (AME) was improved (p<0.01) by 2.1% and 1.8% during starter and grower periods, respectively. There was a main effect (p<0.05) of ${\alpha}$-Gal on the digestion of neutral detergent fiber (NDF) during the starter period and crude protein (CP), NDF and acid detergent fiber (ADF) during the grower period. With the addition of ${\alpha}$-Gal, the relative weight of liver was reduced (p<0.01) during the two phases. The duodenal and jejunal pH were significantly decreased (p<0.01) with the supplementation of ${\alpha}$at the two phases. ${\alpha}$-Gal addition reduced (p<0.01) chyme viscosity of the ileum during the starter and grower periods. Overall, ${\alpha}$-Gal showed a major effect on nutrient efficiency, improved ADG and feed efficiency, whereas LME decreased feed efficiency. The incorporation of ${\alpha}$-Gal into a LME diet could at least partially offset ME deficiency of non-dehulled soybean meal.

• Safety and Health at Work
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• v.8 no.3
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• pp.296-305
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• 2017

Background: Surfactant-containing water sprays are commonly used in coal mines to collect dust. This study investigates the dust collection performance of different surfactant types for a range of coal dust particle sizes and charges. Methods: Bituminous coal dust aerosol was generated in a wind tunnel. The charge of the aerosol was either left unaltered, charge-neutralized with a neutralizer, or positively- or negatively-charged using a diffusion charger after the particles were neutralized. An anionic, cationic, or nonionic surfactant spray or a plain water spray was used to remove the particles from the air flow. Some particles were captured while passing through spray section, whereas remaining particles were charge-separated using an electrostatic classifier. Particle size and concentration of the charge-separated particles were measured using an aerodynamic particle sizer. Measurements were made with the spray on and off to calculate overall collection efficiencies (integrated across all charge levels) and efficiencies of particles with specific charge levels. Results: The diameter of the tested coal dust aerosol was $0.89{\mu}m{\pm}1.45$ [geometric $mean{\pm}geometric$ standard deviations (SD)]. Respirable particle mass was collected with $75.5{\pm}5.9%$ ($mean{\pm}SD$) efficiency overall. Collection efficiency was correlated with particle size. Surfactant type significantly impacted collection efficiency: charged particle collection by nonionic surfactant sprays was greater than or equal to collection by other sprays, especially for weakly-charged aerosols. Particle charge strength was significantly correlated with collection efficiency. Conclusion: Surfactant type affects charged particle spray collection efficiency. Nonionic surfactant sprays performed well in coal dust capture in many of the tested conditions.

• Journal of Korea Port Economic Association
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• v.24 no.4
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• pp.47-70
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• 2008

The purpose of this study is to estimate total factor productivity(TFP) growth by stochastic frontier function and to grasp contributing factors of its growth rate by decomposing the total factor productivity into efficiency change, technical progress, scale change, and allocation change. Annual growth rate of total factor productivity for 1990-2003 is 0.019 (1.9%), higher than that of overall industry (0.010). The main component of TFP growth is not efficiency change but technical progress. Contributing factors of total factor productivity growth are change of allocation efficiency in port industry, technical progress in sea-transportation industry, and change of scale efficiency in transportation-equipment industry. The change of total factor productivity shows a decreasing trend since late in the 1990s. The annual technical efficiency of port-logistics industry is less than that of overall industry. Capital elasticity for output (0.391) is higher than labor elasticity (0.227), but scale economy of port-logistics industry is 0.618, which is far from optimal scale economy.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.3
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• pp.383-387
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• 1994

Six heifers each of $F_1$, $F_2$, $F_3$, $F_4$ H. Friesian $\times$ Sahjwal halfbreds and pure Sahiwal with overall average initial age and live weight of $315.6{\pm}134.8 days$ and $143.8{\pm}48.5kg$, respectively were used for this study. The under trial animals were fed according to N.R.C. (1978). The overall average age at maturity, first conception and first calving was $563.8{\pm}116.8$, $675.8{\pm}135.6$ and $956.8{\pm}149.8days$ with live weights as $302.2{\pm}58.6$, $342.6{\pm}41.5$ and $433.9{\pm}38.1kg$, respectively. The overall 305 days and total milk yield for 1st lactation was $2,729.0{\pm}669.3$ and $2,992.7{\pm}377.5litre$ while the FCM (at 4%) was $2,934.2{\pm}410.8litre$. The lactation length was $336.6{\pm}69.6days$. The fat and solids not fat contents were $4.5{\pm}0.2$ and $8.2{\pm}0.3percent$, respectively. The milk production in Sahiwal cows was significantly lower than crossbred cows. The services per conception were $2.5{\pm}1.3$. The overall per head per day consumption of DM, TCP and ME was $10.9{\pm}1.2kg$, $1,399{\pm}199gm$ and $22.6{\pm}2.4 M.Cal.$, respectively. The overall milk producing efficiency for the production of one litre of FCM was $1.12{\pm}0.15kg$ of DM, $142.2{\pm}17.76gm$ of TCP and $2.31{\pm}0.27M.Cal.$ of energy while the feeding cost was Rs. $1.46{\pm}0.22$ per litre of FCM produced. The feeding cost per litre FCM was significantly higher in Sahiwal and $F_2$ than in other genetic groups.

• Journal of Korea Port Economic Association
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• v.31 no.4
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• pp.39-52
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• 2015

The purpose of this paper is to empirically examine whether there are significant relations among rankings of cross-efficiency, web accessibility, and website evaluation. For this purpose, the study uses the KWAH-4 method developed by the Web Accessibility Laboratory in Korea, website evaluation method developed by the Business Development Bank of Canada (BDC), and the cross-efficiency model for 13 Asian container seaports including Korean, Chinese, and Japanese main ports in 3 years (2009, 2010, and 2013) using data for two cases: three inputs (depth, total area, and number of crane) and one output (TEU) in the first case and three inputs and two outputs (TEU and BDC overall score) in the second case. The main empirical results are as follows. First, the ranking orders of cross-efficiency, web accessibility, and website evaluation overall scores are not significantly correlated with each other. Second, if the BDC overall score is included in the output element, the correlation results are improved. However, the correlation coefficient is still low. The container port policy planners should introduce and consider the web accessibility and website evaluation scores when evaluating an efficiency-increasing plan for Korea's main container ports.