• Membrane Journal
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• v.6 no.3
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• pp.157-165
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• 1996

Polysulfone(PS) membranes were prepared from homogeneous PS solutions by the phase inversion technique. When propionic acid(PA) was added into a casting solution of n-methylpyrrolidone(NMP) and PS, precipitation rate of the solution film was accelerated. This kind of acceleration was consistent, even though a precipitating nonsolvent was changed from water to isopropanol. These phenomena were caused by decrease of nonsolvent tolerance in the casting solution due to addition of PA. PS powder was prepared by precipitation of a 3wt% solution in dimethylformamide(DMF) using ethanol as nonsolvent. Gas adsorption analysis of the powder showed that the capillary condensation sites were found in the powder structure. Membranes prepared from PS solution(15wt%) in NMP had the following characteristics of gas adsorption and water permeation. In gas adsorption analysis, the membrane precipitated using isopropanol showed low uptake of nitrogen gas and the capillary condensation sites were not found. On the contrary, a significant amount of the capillary condensation sites was found in the membrane coagulated by water, which was related to increase of nitrogen uptake. tn the membrane prepared froin the solution including PA, an increase of the Henry's law sites and the Langmuir sites was not found clearly. However, the capillary condensation sites were significantly increased, and the water transport also increased.

• Korean Journal of Poultry Science
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• v.37 no.3
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• pp.237-245
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• 2010

A survey of transovarially transmitted diseases, including salmonellosis [(pullorum disease; PD)/(fowl typhoid; FT)], mycoplasmosis, avian infectious anemia (CIA), and fowl adenovirus infection was conducted in the breeder chickens from August to December in 2009. The numbers of flocks sampled out were: Grand Parents Stock (GPS), 45; Parents Stock (PS) 1,018, Baeksemi breeder (BSB) 54. The seroprevalence of salmonellosis (PD/FT) were 0% (GPS), 3.2% (PS), and 3% (BSB), respectively. A total of 983 chicken farms were affected with FT outbreaks between 2000 and 2008. The incidence of FT in commercial broilers, Baeksemi, commercial layers, native chickens, and broiler breeders was 44.3%, 26.2%, 15.7%, 12.6% and 1.08%, respectively. Of the affected broilers, over 90% birds were under 2 weeks of age, indicating it was possible that they were infected with S. gallinarum via vertical transmission. The sero-positive flocks against Mycoplasma gallisepticum (MG) were 71.1% (GPS), 88.7% (PS), 88.7% (BSB), while the rates of positive flocks against Mycoplasma synoviae (MS) were 86.0% (GPS), 77.0% (PS), and 98.0% (BSB). In GP and parent farms, the detection rates on specific genes of CIA virus were 19/45 (42.2%), and 169/1039 (18.0%), respectively, whereas the seroprevalence of CIA were 86.0% in GPS and 93.7% in PS flocks. In addition, positive flocks of fowl adenoviruses were 4.4% (GPS), 2.7% (PS) and 9.35% (BSB), respectively. As the results, avian mycoplasmosis and CIA have been more prevailing in chicken breeder than avian salmonellosis and fowl adenovirus infection in Korea.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.135-148
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• 2017

Response Surface Methodology (RSM), which is combining with Plackett-Burman design and Box-Behnken experimental design, was applied to optimize the ratios of the nutrient components for carotenoid production by Rhodobacter sphaeroides PS-24 in liquid state fermentation. Nine nutrient ingredients containing yeast extract, sodium acetate, NaCl, $K_2HPO_4$, $MgSO_4$, mono-sodium glutamate, $Na_2CO_3$, $NH_4Cl$ and $CaCl_2$ were finally selected for optimizing the medium composition based on their statistical significance and positive effects on carotenoid yield. Box-Behnken design was employed for further optimization of the selected nutrient components in order to increase carotenoid production. Based on the Box-Behnken assay data, the secondary order coefficient model was set up to investigate the relationship between the carotenoid productivity and nutrient ingredients. The important factors having influence on optimal medium constituents for carotenoid production by Rhodobacter sphaeroides PS-24 were determined as follows: yeast extract 1.23 g, sodium acetate 1 g, $NH_4Cl$ 1.75 g, NaCl 2.5 g, $K_2HPO_4$ 2 g, $MgSO_4$ 1.0 g, mono-sodium glutamate 7.5 g, $Na_2CO_3$ 3.71 g, $NH_4Cl$ 3.5g, $CaCl_2$ 0.01 g, per liter. Maximum carotenoid yield of 18.11 mg/L was measured by confirmatory experiment in liquid culture using 500 L fermenter.

• The Journal of Korean Physical Therapy
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• v.22 no.4
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• pp.73-81
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• 2010

Purpose: The purpose of this study was (1) to examine the effects of a Health Promotion Exercise Program (HPEP) on functional improvement, physical strength (PS) and muscle activation (MA), and the interactive influence with activities of daily living (ADL) and instrumental activities of daily living (IDAL) in the elderly, and (2) to develop and provide a HPEP for the elderly in order to prevent declines and impairments in integrated nerve function and physical capacity. Methods: Our study included relatively healthy elderly people aged 65 years or older. The experimental group, which was composed of 30 people, participated in a HPEP 50~60 minutes a day, 3 times a week, for a total of 12 weeks. Results: Confirmatory factor analysis (CFA) validated the measurement models for MA, physical strength, ADL and IADL with a p<0.01. This confirms (i) the beneficial effects of the ADFP on their MA and PS, and (ii) that their improvement in PS, in turn, can improve their IADL. The results of this study indicates that ADFP can help Korean seniors 65 years or older improve their MA, PS, ADL, and IADL, and do so synergistically. Conclusion: An HPEP, when organized in such a way that the elderly can easily do it, and when exercise items and intensity can be programmed and reorganized accordingly to individual physical and physiological characteristics by presenting 5 categorized health domains of physical strength, may be useful, especially because it can be practiced irrespective of time and place.

• Journal of Advanced Marine Engineering and Technology
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• v.5 no.1
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• pp.12-19
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• 1981

As the fuel oil cost covers from 45% to 60% of the total expenditure for fishing boat operation, the energy saving is now an urgent problem to be taken a countermeasure for engineers, manufacturers or specialists engaging in this field. Undertaking a second-hand engine of the trainging ship, the author made several reconstructions to restore its performances. By inserting foot linears of connecting rods the compression ratio was increased and by adjusting both the fuel injection timing and the cooling water outlet temperature, its thermal efficiency was improved. The results of the experimental operation were summarized as follows. 1. By raising the piston top position 0.75mm more than the value of the operating manual, the compression pressure increased 1.3 kg/$cm^2$ and the maximum pressure did 3.4 kg/$cm^2$ at 75% load. 2. At 75% load, the difference of the maximum pressure between each cylinder was decreased from 2.4 kg/$cm^2$ to 1.8 kg/$cm^2$. 3. The fuel consumption was decreased about 8 g/ps.h at 75% load, and about 5.3 g/ps.h at 85% load. 4. The brake thermal efficiency was improved about 1.5% at 75% load and 0.9% at 85% load.

• Food Science and Preservation
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• v.18 no.2
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• pp.256-265
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• 2011

To investigate the effect of a solar salt on Kimchi fermentation, Chinese cabbages were brined with four-years aged solar salt (FS), one-year aged solar salt (OS), and purified salt (PS). The Kimchi was fermented at $7^{\circ}C$ for 33 days. The changes in pH and acidity of the Kimch brined with PS was slower than those of Kimchis brined with FS and OS. In the Kimchis with FS and OS, lactic acid bacteria (LAB) counts increased from 7.10~7.22 log CFU/mL at 0 day to 9.26~9.42 log CFU/mL at 12 days, after which counts slightly decreased to 8.04~8.75 log CFU/mL by 33 days of fermentation. The LAB counts of the kimchi with PS slowly increased from 7.24 log CFU/mL at 0 day to 8.99 log CFU/mL at 27 days, after then which counts sharply decreased to 7.92 log CFU/mL by 33 days of fermentation. Yellowness (b) color values of the kimchi with PS (59.10) was higher than the Kimchi with FS (53.68) and the Kimchi with OS (53.77). Hardness of the Kimchi with FS was more firm than the other Kimchis after 33 days storage. Sensory evaluation of the Kimchi with FS showed higher score than that of the other Kimchis.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.2
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• pp.7-13
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• 2011

This paper presents a Time-to-Digital Converter which is a key block of an All-Digital Phase Locked Loop. In this work, a Vernier Delay Line is added in a conventional Gated Ring Oscillator, so it could get multi-phases and a high resolution. The Gated Ring Oscillator uses 7 unit delay cell, the Vernier Delay Line is used each delay cell. So proposed Time-to-Digital Converter uses total 21 phases. This Time-to-Digital Converter circuit is designed and laid out in $0.13{\mu}m$ 1P-6M CMOS technology. The proposed Time-to-Digital Converter achieves 26ps resolution, maximum input signal frequency is 100MHz and the digital output of proposed Time-to-Digital Converter are 8-bits. The proposed TDC detect 5ns phase difference between Start and Stop signal. A power consumption is 8.4~12.7mW depending on Enable signal width.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.236-245
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• 2023

We investigated the basic vegetative phase (BVP), photoperiod-sensitivity (PS), and thermo-sensitivity (TS) of 40 rice varieties to characterize their heading ecology that is adaptable to North Korean rice production areas. The ranges were 12 - 43 days for BVP, 0 - 74 days for PS, and 15 - 33 days for TS, depending on the variety. The number of days from transplanting to the heading stage (DTH) was significantly correlated with PS in the 13 major rice production regions where all 40 varieties (including early-, middle-, and mid-late-maturing varieties) were tested. DTH was significantly correlated with BVP and TS but not with PS in the 10 low-temperature regions where only 28 early-maturing varieties were tested. The heading ecology of the adaptable varieties for each region could be characterized by an exponential equation between the BVP and PS of varieties that headed at the border of the safe marginal heading date (SMHD) for each of the seven regional environments (Kaesong, Haeju, Yongyon, Singye, Sariwon, Nampo, and Pyongyang). A PS of 25 - 30 days or less was an additional adaptive trait in the Sariwon and Pyongyang environments. The varieties that reached the heading stage not later than the SMHD in six regional environments (Anju, Kusong, Sinuiju, Changjon, Wonsan, and Supung) and those that reached the heading stage not later than the late marginal heading date (LMHD) in four regional environments (Hamhung, Pyonggang, Huichon, and Kanggye) had both a PS of 26 days or less and a BVP of 25 - 28 days or less. In the Yangdok, Sinpo, and Chunggang environments, varieties that reached the heading stage not later than the LMHD for each region had a BVP of 15 - 20 days or less. The results suggested that a shortened BVP trait should be introduced to existing early-maturing rice varieties to reduce the duration of growth period to reach the heading stage.

• Journal of agricultural medicine and community health
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• v.25 no.2
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• pp.265-273
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• 2000

Benign prostatic hyperplasia (BPH) is a highly prevalent, age-related disorder in men which place a considerable burden on health care resources worldwide. While BPH and hypertension are apparently diverse disease processes, they have some features in common(e.g. underlying etiology of the sympathetic nervous system). The purpose of this study is to estimate the prevalence of lower urinary tract symptoms using I-PSS(international prostate symptom score) and to investigate the association of hypertension with I-PSS. This study was carried out to 390 men(40~86 year old) at 3 Myun in Chungju City from July to August, 1997. Subjects answered on questionnaire for I-PSS and were checked age, education, marital status, annual income, blood pressure. The mean age of subjects was 59.8 year old. The mean of I-PSS were increased by age decades(40~49, 50~59, 60~69, 70~86) and it's scores were 4.4, 7.0, 8.2, 12.3 respectively. Strong correlations were observed between the I-PSS and the QUL(quality of life)(P=0.0001). I-PSS(mean-value) were 7.85 in hypertensive group and 8.39 in normotensive group but there was no statistically significance between the two groups(P>0.05). The proportion of mean scoring greater than 8 was 42.5%. There have been reports of association between lower urinary tract symptoms and hypertension, but there was no consistent suggestion that such an association could be casual. The need for high-quality epidemiological information and consequent increased prospects for prevention is obvious.

• Bulletin of the Korean Chemical Society
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• v.31 no.2
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• pp.360-364
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• 2010

$Li_4Ti_5O_{12}$ thin film with inverse hemispheric structure was fabricated on a Pt/Ti/$SiO_2$/Si substrate by the sol-gel and dip coating method for use as an anode for 3-dimensional (3D) thin-film batteries. Polystyrene (PS) beads of 400 nm diameter were used to prepare the template for the inverse hemispheric structure. A coating solution prepared using precursor sources was dropped on the template-deposited substrates, which were then calcinated at $400^{\circ}C$. The template was removed by calcination, and the inverse hemispheric structure was successfully formed by an annealing process. The cyclic performance during high-rate charge/discharge processes of the $Li_4Ti_5O_{12}$ film with inverse hemispheric structure was superior to that of the flat $Li_4Ti_5O_{12}$ film.