• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.4
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• pp.29-41
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• 2014

The Korean government has purchased land properties alongside any significant water bodies before setting up the buffers to secure water qualities. Since the annual budgets are limited, however, there has always been the issue of which land parcels ought to be given the priority. Therefore, this study aims to develop efficient mechanism for land acquisition priorities in stream corridors that would ultimately be vegetated for riparian buffer zones. The criteria of land acquisition priority were driven through literary review along with experts' advice. The relative weights of their value and priorities for each criterion were computed using the Analytical Hierarchy Process(AHP) method. Major findings of the study are as follows: 1. The decision-making structural model for land acquisition priority focuses mainly on the reduction of non-point source pollutants(NSPs). This fact is highly associated with natural and physical conditions and land use types of surrounding areas. The criteria were classified into two categories-NSPs runoff areas and potential NSPs runoff areas. 2. Land acquisition priority weights derived for NSPs runoff areas and potential NSPs runoff areas were 0.862 and 0.138, respectively. This implicates that much higher priority should be given to the land parcels with NSPs runoff areas. 3. Weights and priorities of sub-criteria suggested from this study include: proximity to the streams(0.460), land cover(0.189), soil permeability(0.117), topographical slope(0.096), proximity to the roads(0.058), land-use types(0.036), visibility to the streams(0.032), and the land price(0.012). This order of importance suggests, as one can expect, that it is better to purchase land parcels that are adjacent to the streams. 4. A standard scoring system including the criteria and weights for land acquisition priority was developed which would likely to allow expedited decision making and easy quantification for priority evaluation due to the utilization of measurable spatial data. Further studies focusing on both point and non-point pollutants and GIS-based spatial analysis and mapping of land acquisition priority are needed.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.364-371
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• 2014

BACKGROUND: To evaluate the impact of rapid temperature change at spring and the early summer seasons in climate change, we have investigated the physiological response and yield of onion in a greenhouse with thermostat control system. METHODS AND RESULTS: Seedlings of onion(cv. Sunshine) were planted on October 30, 2012 and harvested on May 30, 2013. The used treatments(March-April-May) for a rapid temperature change were T0(control): $6.0-10.4-17.2^{\circ}C$, T1: $6.0-5.4(-5)-17.2^{\circ}C$, T2: $6.0-10.4-22.2(+5)^{\circ}C$ and T3: $6.0-5.4(-5)-22.2(+5)^{\circ}C$. Total yields of bulb within the temperature change as high temperature treatment T2 and control treatment T0 were increased significantly(p<0.05), as compared to the low temperature treatment T1. Low temperature conditions significantly (p<0.05) reduced plant height, SPAD reading, crude protein and fiber etc., as compared to the TO and T2. CONCLUSION: The rapid temperature changes were highly affected by low temperature than high temperature. These results suggest that rapid climate change of future could need systematic standard model for physiological characteristics and yields of onion.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.233-238
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• 2020

Although the interest in NBR has been increasing due to the recent developments of the aerospace sector, there are few reports on HNBR's aeronautical oil, particularly evaluations of the accelerated life of harsh factors. In this study, the tensile strength was adopted as a performance evaluation factor to evaluate the accelerated life of HNBR used in the aviation field. The accelerated stress factor affecting the performance-aging characteristics was defined as temperature. The acceleration stress factor was determined to be temperature, and the result of measuring the tensile strength change over time. The sample for the acceleration condition was taken out of the oven for a certain period and left at room temperature for 24 hours. The dumbbell type 3 specimens were manufactured according to the standard specified in KS M 6518 and were measured the tensile strength, a factor in accelerated life evaluations. The activation energy was 0.895, and the shape parameter was 1.152 using the Arrhenius model. The characteristic life obtained from the tensile strength of the HNBR specimen immersed in aviation oil at 20℃ was 272,256 hours; the average life was 258,965 hours, and the B10 life was 38,624 hours.

• Journal of Animal Science and Technology
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• v.50 no.1
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• pp.19-26
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• 2008

Heritability and genetic correlation for growth traits in Duroc pig breed were estimated using Bayesian method via Gibbs sampling. The data set consisted of 3,526 performance records at National Institute of Animal Science. For estimating those parameters using Gibbs sampling, 5,000 cycles of ‘burn-in’ period were discarded among a total of 55,000 samples. Out of the remaining 50,000 samples, 5,000 estimates by each parameter were retained and used for analyses to avoid any correlation among adjacent samples. The growth traits considered in this study were average daily gain at 30kg(ADG1), average daily gain at 90kg(ADG2), backfat thickness(BF), days to 90kg(D90) and feed conversion ratio(FC). The estimated heritabilities and their standard deviation using Gibbs sampler were 0.43±0.04, 0.49±0.038, 0.31±0.040, 0.48±0.039 and 0.62±0.086, respectively. Genetic correlations were －0.02, －0.13, －0.55 and －0.15 between ADG1 with ADG2, BF, D90 and FC, respectively, 0.16, －0.73, －0.32 between ADG2 with BF, D90 and FC respectively, 0.01, －0.08 between BF with D90, FC, respectively, and 0.23 between D90 with FC.

• Journal of Korea Technology Innovation Society
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• v.19 no.3
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• pp.439-464
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• 2016

The technical regulation and conformity assessment procedure of our country on ICT equipments is currently required to have more innovation due to the request of main trade countries, the second phase conclusion of MRA, necessity of expansion of conformity assessment service market and demand of manufacturers. The world's leading advanced countries have already proceeded with innovation based on privatization plan. According to the comparative analysis of the level, it turned out that Japan obtained the highest level of privatization while South Korea ranked the lowest level. According to the research result of examination and certification ability of private institutions of our country, it turned out that our country is expected to have possibility of achieving higher level of privatization than that of the present. Moreover, according to the questionnaire survey conducted to the persons concerned regarding privatization direction, they gave positive response to all the indicated survey contents of privatization direction in terms of "delegation of certification services to private sectors (contracting-out)", "transformation of EMC into private voluntary standard" and "changeover of conformity assessment agent". However, from the view of acceptance and conflict model, it is estimated that starting from "delegation of certification services to private sectors (contracting-out)" seems to be the most advisable plan. Also, prior to privatization, it is required to improve relevant systems such as certification examiner system.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.1
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• pp.36-44
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• 2007

This paper presented a hybrid ternary encoding scheme using 3-valued logic. It can adapt to the delay-insensitive(DI) model. We designed an asynchronous wrapper for the hybrid ternary encoding scheme to communicate with various asynchronous encoding schemes. It reduced about 50% of transmission lines and power consumption compared with the conventional 1-of-4 and ternary encoding scheme. The proposed wrappers were designed and simulated using the $0.18-{\mu}m$ standard CMOS technology. As a result, the asynchronous wrapper operated over 2 GHz communicating with a system bus. Moreover, the power dissipation of the system bus adapted the hybrid ternary encoding logic decreases 65%, 43%, and 36% of the dual-rail, 1-of-4, and ternary encoding scheme, respectively. The proposed data encoding scheme and the wrapper circuit can be useful for asynchronous high-speed and low-power asynchronous interface.

• Journal of the Korean Geotechnical Society
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• v.32 no.12
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• pp.79-91
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• 2016

Geosynthetic-reinforced and Pile-supported (GRPS) embankment method is widely used to construct structures on soft ground due to restraining residual settlement and their rapid construction. However, effect of cyclic loading has not been established although some countries suggest design methods through many studies. In this paper, cyclic loading tests were conducted to analyze dynamic load transfer characteristics of pile-supported embankment reinforced with geosynthetics. A series of 3 case full scale model tests which were non-reinforced, one-layer-reinforced, two-layer reinforced with geosynthetics were performed on piled embankments. In these series of tests, the height of embankment and pile spacing were selected according to EBGEO (2010) standard in Germany. As a result of the vertical load parts on the pile and on the geosynthetic reinforcement measured separately, cyclic loads transferred by only arching effect decreased with strength geosynthetic-reinforced case. However, final loads on the pile showed no differences among the cases. These results conflict with previous studies that reinforcement with geosynthetics increases transfer load concentrated on piles. In addition, it is observed that the load transferred to pile decreases at the beginning of cycle number due to reduction of arching effected by cyclic loading. Based on these results, transferred mechanism for cyclic load on GRPS system has been presented.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.769-774
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• 1993

Defatted rice bran was microparticulated using fluidized bed opposed jet mill and air-classified at different air classifying wheel speed (ACWS) in Turboplex classifier. The median particle size and the standard deviation decreased, and concomitantly the specific surface area increased generally with increasing ACWS. The protein, fat and ash contents of the recovered rice bran increased with ACWS. The contents of minerals; magnesium, zinc, iron and manganese; increased positively with ACWS. The phytic acid content, however, was slightly higher at middle ACWS. The dietary fiber content was highest in the ACWS 15,000 rpm fraction showing 31.47%. Higher ACWS resulted in lighter colored powder. The water holding capacity (WHC) showed the maximum value at ACWS 12,000 rpm and decreased with increasing ACWS, while the oil holding capacity (OHC) increased with ACWS. The rheological property of the microparticulated rice bran/water suspension fitted to the linear model. The yield stress and viscosity of the suspension increased with ACWS. The shape of microparticulated rice bran at ACWS 21,000 rpm was spherical, and the median particle size was $3.7{\mu}m$. When cake was prepared with substitution of microparticulated rice bran at 5%, the cake height and volume increased remarkably.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.138-147
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• 2020

The construction field is one of the most representative job creation businesses, but it has been pointed out that the overall quality of the jobs is low because of the nature of the order-made production industry, such as unstable employment structure, aging workforce, etc.. Accordingly, the government plans to implement the "prevailing wage system" that guarantees a minimum wage for construction site workers. In reality, however, only a market wage could be used for a construction cost estimation because there was no standard for the prevailing wage. A comparative analysis of the prevailing wage and market wage was performed. This paper proposes a framework for estimating the reasonable prevailing wage in the construction industry. The results showed that the prevailing wage was estimated to be 4.7% lower than the market wage when the proposed framework is applied to the carpenters' case. This suggests that the proposed model could be used as an alternative for market wage considering the original purpose of the prevailing wage. This study will construct the basic data for scientific analysis on the wage, and finally, help estimate the reliable prevailing wage in the future.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.1054-1060
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• 2017

Objective: This study was aimed at evaluating effects of cattle breed resources and alternative mixed-feeding practices on meat productivity and emission intensities from household farming systems (HFS) in Daklak Province, Vietnam. Methods: Records from Local $Yellow{\time}Red$ Sindhi (Bos indicus; Lai Sind) and 1/2 Limousin, 1/2 Drought Master, and 1/2 Red Angus cattle during the growth (0 to 21 months) and fattening (22 to 25 months) periods were used to better understand variations on meat productivity and enteric methane emissions. Parameters were determined by the ruminant model. Four scenarios were developed: (HFS1) grazing from birth to slaughter on native grasses for approximately 10 h plus 1.5 kg dry matter/d (0.8% live weight [LW]) of a mixture of guinea grass (19%), cassava (43%) powder, cotton (23%) seed, and rice (15%) straw; (HFS2) growth period fed with elephant grass (1% of LW) plus supplementation (1.5% of LW) of rice bran (36%), maize (33%), and cassava (31%) meals; and HFS3 and HFS4 computed elephant grass, but concentrate supplementation reaching 2% and 1% of LW, respectively. Results: Results show that compared to HFS1, emissions ($72.3{\pm}0.96kg\;CH_4/animal/life$; least squares $means{\pm}standard$ error of the mean) were 15%, 6%, and 23% lower (p<0.01) for the HFS2, HFS3, and HFS4, respectively. The predicted methane efficiencies ($CO_2eq$) per kg of LW at slaughter ($4.3{\pm}0.15$), carcass weight ($8.8{\pm}0.25kg$) and kg of edible protein ($44.1{\pm}1.29$) were also lower (p<0.05) in the HFS4. In particular, irrespective of the HSF, feed supply and ratio changes had a more positive impact on emission intensities when crossbred 1/2 Red Angus cattle were fed than in their crossbred counterparts. Conclusion: Modest improvements on feeding practices and integrated modelling frameworks may offer potential trade-offs to respond to climate change in Vietnam.