• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.440-447
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• 2020

The demand for large-scale horticultural complexes utilizing reclaimed lands is increasing, and one of the pending issues for the construction of large-scale facilities is to establish foundation design criteria. In this paper, we tried to review previous studies on the method of reinforcing the foundation of soft ground. Target construction methods are spiral piles, wood piles, crushed stone piles and PF (point foundation) method. In order to evaluate the performance according to the basic construction method, pull-out resistance, bearing capacity, and settlement amount were measured. At the same diameter, pull-out resistance increased with increasing penetration depth. Simplified comparison is difficult due to the difference in reinforcement method, diameter, and penetration depth, but it showed high bearing capacity in the order of crushed stone pile, PF method, and wood pile foundation. In the case of wood piles, the increase in uplift resistance was different depending on the slenderness ratio. Wood, crushed stone pile and PF construction methods, which are foundation reinforcement works with a bearing capacity of 105 kN/㎡ to 826 kN/㎡, are considered sufficient methods to be applied to the greenhouse foundation. There was a limitation in grasping the consistent trend of each foundation reinforcement method through existing studies. If these data are supplemented through additional empirical tests, it is judged that a basic design guideline that can satisfy the structure and economic efficiency of the greenhouse can be presented.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.5
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• pp.25-33
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• 2011

This work proposes a skinny-type 10b 50MS/s 0.13um CMOS three-step pipeline ADC for CIS applications. Analog circuits for CIS applications commonly employ a high supply voltage to acquire a sufficiently acceptable dynamic range, while digital circuits use a low supply voltage to minimize power consumption. The proposed ADC converts analog signals in a wide-swing range to low voltage-based digital data using both of the two supply voltages. An op-amp sharing technique employed in residue amplifiers properly controls currents depending on the amplification mode of each pipeline stage, optimizes the performance of op-amps, and improves the power efficiency. In three FLASH ADCs, the number of input stages are reduced in half by the interpolation technique while each comparator consists of only a latch with low kick-back noise based on pull-down switches to separate the input nodes and output nodes. Reference circuits achieve a required settling time only with on-chip low-power drivers and digital correction logic has two kinds of level shifter depending on signal-voltage levels to be processed. The prototype ADC in a 0.13um CMOS to support 0.35um thick-gate-oxide transistors demonstrates the measured DNL and INL within 0.42LSB and 1.19LSB, respectively. The ADC shows a maximum SNDR of 55.4dB and a maximum SFDR of 68.7dB at 50MS/s, respectively. The ADC with an active die area of 0.53$mm^2$ consumes 15.6mW at 50MS/s with an analog voltage of 2.0V and two digital voltages of 2.8V ($=D_H$) and 1.2V ($=D_L$).

• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.543-550
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• 2003

Two experiments were conducted to determine the effects of deletion of vitamin and trace mineral premixes on growth, feed efficiency, backfat thickness, hemoglobin content, muscle vitamin E content, and fecal, serum and muscle trace mineral contents in finishing pigs raised under two different housing conditions. In Exp. 1, three pens (or experimental units) of five pigs each (average weight $\pm$ s.e., 70 $\pm$ 0.5 kg) were assigned to a control diet (with vitamin and trace mineral premixes) or diets with 50 or 100% of the premixes deleted. Pigs were fed to market weight under sub-optimal housing conditions with sawdust-covered concrete floor and no electrical ventilation. In Exp. 2, three pens of four pigs each (average weight $\pm$ s.e., 56 $\pm$ 1.1 kg) were assigned to a control (with vitamin and trace mineral premixes), Diet-P (100% of the premixes deleted) or Diet-P+E (Diet-P plus 100 mg $\alpha$-tocopherol acetate/kg diet fed for the last 2 wk before slaughter). Pigs were fed to market weight under optimal housing conditions with 70%-slatted concrete floor, electrical ventilation and temperature control. No significant differences were found in average daily gain (ADG), average daily feed intake (ADFI), and gain/feed among treatments in both experiments, but in Exp. 2 done with younger pigs, ADG and ADFI tended to be higher in the control group than in pigs fed diet without premixes. Hemoglobin content, hematocrit and red blood cell count were not influenced by the deletion of premixes. Backfat thickness was not different among treatments. Fecal Mn (twofold) and Zn (threefold) contents were higher in the control than in pigs fed diets without the premixes. Serum trace mineral contents were not influenced by diets. $\alpha$-Tocopherol content in gluteus maxima was decreased (P< 0.01) by deleting the dietary premixes, but increased to the level higher than the control by adding 100 mg $\alpha$-tocopheryl acetate/kg diet fed for the last 2 wk before slaughter. Results indicate that: 1) supplementary vitamins and trace minerals may not be necessary for optimum growth in finishing pigs, and 2) deletion of the dietary premixes reduces muscle vitamin E content, but the reduced content can be reversed by adding $\alpha$- tocopherol to diets fed for the last 2 wk before slaughter. The deletion may help to alleviate the environmental load of certain minerals from manure.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.3
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• pp.3-9
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• 2017

Recently, in 3rd Generation Partnership Project(3GPP), there is a study of the Long Term Evolution(LTE) based vehicle communication which has been actively conducted to provide a transport efficiency, telematics and infortainment. Because the vehicle communication is closely related to the safety, it requires a reliable communication. Because vehicle speed is very fast, unlike the movement of the user, radio channel is rapidly changed and generate a number of problems such as transmission quality degradation. Therefore, we have to continuously updates the channel estimates. There are five types of conventional channel estimation scheme. Least Square(LS) is obtained by pilot symbol which is known to transmitter and receiver. Decision Directed Channel Estimation(DDCE) scheme uses the data signal for channel estimation. Constructed Data Pilot(CDP) scheme uses the correlation characteristic between adjacent two data symbols. Spectral Temporal Averaging(STA) scheme uses the frequency-time domain average of the channel. Smoothing scheme reduces the peak error value of data decision. In this paper, we propose the novel channel estimation scheme in LTE based Vehicle-to-Vehicle(V2V) environment. In our Hybrid Reliable Channel Estimation(HRCE) scheme, DDCE and Smoothing schemes are combined and finally the Linear Minimum Mean Square Error(LMMSE) scheme is applied to minimize the channel estimation error. Therefore it is possible to detect the reliable data. In simulation results, overall performance can be improved in terms of Normalized Mean Square Error(NMSE) and Bit Error Rate(BER).

• Applied Chemistry for Engineering
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• v.17 no.3
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• pp.243-249
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• 2006

Porous polymer gel electrolytes (PGEs) based on poly(vinylidenefluoride-co-hexafluoropropylene) (P(VdF-co-HFP)) as a polymer matrix and polyvinylpyrolidone (PVP) as a pore-forming agent were prepared and electrochemical properties were investigated for an electric double layer capacitor (EDLC) in order to increase a permeability of an electrolyte into the PGE. Propylene carbonate (PC) and ethylene carbonate (EC) as plasticizers, and tetraethylammonium tetrafluoroborate ($TEABF_4$) as a supporting salt for the PGE were used. EDLC unit cells were assembled with the PGE and electrode comprising BP-20 and MSP-20 as activated carbon powders, Super P as a conducting agent, and P(VdF-co-HFP)/PVP as a mixed binder. Ion conductivity of PGEs increased with an increased PVP content and was the best at 7 wt% PVP, whereas electrochemical characteristics such as AC-ESR of unit cell were better in 3 wt%. And electrochemical characteristics of the unit cell with PGE were the best at a 33 : 33 weight ratio of PC to EC. Specific capacitance of a mixed plasticizer system of PE and EC was higher than that of pure PC. Ion conductivity of PGEs with a film thickness of $20{\mu}m$ was higher, but electrochemical characteristics of unit cells were higher for a $50{\mu}m$ membrane thickness. Also, the unit cell has shown the highest capacitance of 31.41 F/g and more stable electrochemical performance when PGE and electrode were hot pressed. Consequently, the optimum composition ratio of PGE for EDLCs was 23 : 66 : 11 wt% such as P(VdF-co-HFP) : PVP = 20 : 3 wt% and PC : EC = 44 : 22 wt%. In this case, $3.17{\times}10^{-3}S/cm$ of ion conductivity was achieved at the $50{\mu}m$ thickness of PGE for EDLCs. And the electrochemical characteristics of unit cells were $2.69{\Omega}$ of DC-ESR, 28 F/g of specific capacitance, and 100% of coulombic efficiency.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1505-1514
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• 2022

Image matching is a crucial preprocessing step for effective utilization of multi-temporal and multi-sensor very high resolution (VHR) satellite images. Deep learning (DL) method which is attracting widespread interest has proven to be an efficient approach to measure the similarity between image pairs in quick and accurate manner by extracting complex and detailed features from satellite images. However, Image matching of VHR satellite images remains challenging due to limitations of DL models in which the results are depending on the quantity and quality of training dataset, as well as the difficulty of creating training dataset with VHR satellite images. Therefore, this study examines the feasibility of DL-based method in matching pair extraction which is the most time-consuming process during image registration. This paper also aims to analyze factors that affect the accuracy based on the configuration of training dataset, when developing training dataset from existing multi-sensor VHR image database with bias for DL-based image matching. For this purpose, the generated training dataset were composed of correct matching pairs and incorrect matching pairs by assigning true and false labels to image pairs extracted using a grid-based Scale Invariant Feature Transform (SIFT) algorithm for a total of 12 multi-temporal and multi-sensor VHR images. The Siamese convolutional neural network (SCNN), proposed for matching pair extraction on constructed training dataset, proceeds with model learning and measures similarities by passing two images in parallel to the two identical convolutional neural network structures. The results from this study confirm that data acquired from VHR satellite image database can be used as DL training dataset and indicate the potential to improve efficiency of the matching process by appropriate configuration of multi-sensor images. DL-based image matching techniques using multi-sensor VHR satellite images are expected to replace existing manual-based feature extraction methods based on its stable performance, thus further develop into an integrated DL-based image registration framework.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.2
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• pp.127-136
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• 1994

Diffusional sampling devices offer many advantages for measuring concentration levels of industrial contaminants than the conventional pump and charcoal tubes because they are lightweight, require no power, pump or tubing. This study designed to evaluate and compare the sampling performance of passive sampler to charcoal tube from mixed organic solvent workplace with 181 organic solvent using workers working in different concentration of organic solvents. All study workers kept both devices in their breathing zone simultaneuosly in the workplaces, and the sampling analytical results were compared with those of charcoal tube. The results obtained are as follows: 1. The concentrations of toluene and xylene measured by passive sampler were slightly higher than those of charcoal tube, but there were no significant statistical differences between two methods. 2. The concentrations of MEK and cyclo-hexanone measured by passive sampler in low exposure workplace (below 0.20 of MEK TLV levels and 0.1 of cyclo-hexanone TLV levels) were about 2 times higher than that of charcoal tube sampling. While, absorption efficiency of passive sampler was reduced according to increasing concentration measurements of MEK and cyclo-hexanone in air. 3. The ratios of concentrations of toluene, xylene, MEK and cyc1o-hexanone measured by passive sampler over those measured by charcoal tube were 1.11, 1.07, 1.63 and 3.65 respectively. 4. The percentages of concentration of passive samplers within 0.75 and 1.25 of charcoal tube value as a reference value of 1.0 were 57% in toluene, 74% in xylene, 34% in MEK and 32% in cyclo-hexanone respectively. 5. The correlation coefficients of toluene, xylene, MEK and cyclo-hexanone between passive sampler and charcoal tube sampler were 0.963, 0.957, 0.943 and 0.562 with statistical significance.

• Journal of Plant Biotechnology
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• v.42 no.2
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• pp.71-76
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• 2015

Developed countries have set seed industry as a new growth engine, which demands strong support from the government. Multinational seed companies such as Monsanto and DuPont have made huge financial investment to secure their major roles in the global market. To spur domestic seed industry performance, Korean government laid out the foundation for developing seed industry through policy promotion in the late 2000s. In this paper, I look at the current state of the domestic and international seed market to provide information for improving the efficiency of the propulsion of the Golden Seed Project (GSP) along with its vision. The increasing size of global giant companies has been regarded to monopolize the world seed industry wherein ten renowned companies occupy 73% of the overall global market. In effect, this causes a price hike due to limited seed choices. Domestic seed market has been stuck in a range due to a sustained low agricultural production resulting in decreased seed demand and market size. Though breeding technologies for rice and vegetables are world-class, the technologies for top global crops such as cabbage, paprika, and forage are insufficient therefore professionals in this field are not easily employed. Moreover, there is a lack in appropriate infrastructure set up in the universities which adds to ineffective training of professionals. Being a key-supporting industry for agriculture, seed industry should be granted with strong and sustainable investment support from the government. In view thereof, GSP, which started in 2012, ambitions to spur researches outlined by excellent professionals in universities and seed companies aimed to drive seed export volume and quality and attain domestic seed self-sufficiency through adoption of export- and import-substitution seed types (10 varieties each) development strategies. To develop Korea's seed industry excellent achievement of GSP's goals should be drawn successfully and to do this beside development of high quality seeds, support programs for promotion of seed exports are also needed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.633-643
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• 2013

This study investigated the efficiency of university foodservice operations by analyzing the effect of consumer's perception towards university foodservice quality. University students in the Jeonnam area were surveyed and 571 out of 700 surveys were chosen (response rate: 97.0%). SPSS (ver. 20.0) was used to conduct descriptive analysis, factor analysis, reliability analysis, t-test, and multiple regression analysis. The results show that 21.9% of university students have never used the university foodservice, while 48.7% of university students have eaten there 1~2 times per week. The most common reasons reported for avoiding the university foodservice were a limited menu selection (51.5%) and an untasty food (45.8%). The perception of overall service quality at the university foodservice scored relatively low (3.01 points), compared with its importance (3.89 points). The food taste, menu variety, and quality of food ingredients are factors that require improvement for operational strategies by the importance-performance analysis (IPA). The food factors (taste, variety, and quality) among university foodservice qualities had a significantly positive effect on consumers' overall satisfaction (p<0.001), perceived value (p<0.01), intent to recommend (p<0.001), and intent to revisit (p<0.01). These result indicate that the university foodservice management should focus on developing food factors and strive to meet the needs of university students through continuous customer surveys.

• Journal of Animal Science and Technology
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• v.51 no.5
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• pp.395-406
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• 2009

Fifty four Hanwoo steers in final fattening period were assigned to 3 groups control, top dressed $PROSOL^{(R)}$ as an emulsifier (TP) and DSP group (experimental diet made to down spec of nutrients with $PROSOL^{(R)}$, which is sodium stearoyl-2-lactylate), based on the body weight (647.96${\pm}$41.31 kg) and months of age (27.3${\pm}$0.8 mo), and the experiment was conducted to establish the reasonable fattening method of Hanwoo steers for 91 days. Average daily body gains during trial were 0.94, 0.84 and 0.98 kg in control, TP and DSP, respectively (P=0.011). DDMI/ADG of TP group tend to lightly improving compared to control and DSP group (P=0.692). There was no effect of supplementation of the $PROSOL^{(R)}$ in concentrates on growth rate, feed efficiency and shrinkage in Hanwoo steers during the short final fattening period. MQI from TP and DSP was not different based on the rib-eye area and carcass weight in carcass than that from control. Back fat thickness tended to be thicker than control (P>0.05). Marbling score, texture and maturity for TP and DSP was abundantly to increase compared to control (P<0.003). There was significantly increment in supplemented $PROSOL^{(R)}$ (P<0.0001). The meat quality grade of control, TP and DSP were 2.94, 3.78 and 4.50, respectively. Related to this result, the auction price (carcass/kg) were gained significantly (P<0.003) from control (17,560), TP (18,586) and DSP (19,266 won) so which the monetary return was the highest in DSP and the differences was recognized between TP and DSP. Percentage over 1st grade appeared in control, TP and DSP were 55.4, 88.9 and 100.0%, respectively. These results supported the hypothesis that supplementation of emulsifier improve the marbling score and the carcass quality grade by increased digestibilities of the feed fat in Hanwoo steers in fattening period.