• Journal of IKEEE
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• v.14 no.1
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• pp.33-39
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• 2010

In this paper, a 5Gb/s receiver with an adaptive equalizer for serial link interfaces is proposed. For effective gain control, a least-mean-square (LMS) algorithm was implemented with two internal signals of slicers instead of output node of an equalizing filter. The scheme does not affect on a bandwidth of the equalizing filter. It also can be implemented without passive filter and it saves chip area and power consumption since two internal signals of slicers have a similar DC magnitude. The proposed adaptive equalizer can compensate up to 25dB and operate in various environments, which are 15m shield-twisted pair (STP) cable for DisplayPort and FR-4 traces for backplane. This work is implemented in $0.18-{\mu}m$ 1-poly 4-metal CMOS technology and occupies $200{\times}300{\mu}m^2$. Measurement results show only 6mW small power consumption and 2Gbps operating range with fabricated chip. The equalizer is expected to satisfy up to 5Gbps operating range if stable varactor(RF) is supported by foundry process.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.4
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• pp.50-61
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• 2013

In order to generate a renewable energy-Methane, anaerobic systems fed with source separated food waste from university cafeteria were studied. At first, four reactors were evaluated with same feed components; content non-mixing anaerobic reactor without leachate withdrawal/recirculation, content mixing anaerobic reactor without leachate withdrawal/recirculation, content non-mixing anaerobic reactor with leachate withdrawal/recirculation and content mixing anaerobic reactor with leachate withdrawal/recirculation. From the first study, content non-mixing anaerobic reactor with leachate withdrawal/recirculation showed the highest gas production. From further study with this system, it was observed that leachate permeation rate within anaerobic reactor was very important factor for gas generation. The higher permeation rate, the more gas production was observed. It is assumed that 1kg of gas collector weight and C/N ration above 10 in food waste may cause gas consumption in the anaerobic reactor. The gas consumption was estimated by negative pressure build-up at gas collector. The negative pressure build-up must be explained to produce Methane from Food Waste.

• Journal of Preventive Medicine and Public Health
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• v.35 no.3
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• pp.255-262
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• 2002

Objectives : To investigate the fetal cholesterol levels and related factors in a rural adult population. Methods : 3,207 adults(1,272 men and 1,935 women) were examined in 1997 Their heights, weights, and fasting serum total cholesterol levels were measured, and their body mass indices were calculated. A questionnaire interviewing method was used to collect risk factor data. Results : The mean value of total cholesterol were 190.5 mg/dl, and 198.8 mg/dl, and the age-adjusted prevalence rates for hypercholesterolemia (above 240 mg/dl) were 13.7% and 10.2%, in men and women, respectively. From simple analyses, age, educational level, coffee intake, amount of meat and food intake, waist circumference, waist-hip circumference ratio(WHR), and body mass index(BMI) were significant risk factors in men (p<0.05) relating to serum total cholesterol levels. In women, age, educational level, hypertension history, diabetes history, herbal drug history, amount of feed intake, alcohol consumption, waist circumference, WHR, BMI, and menopausal status were significant risk factors (p<0.05). In multiple linear regression analyses, waist circumference (p<0.01), BMI (p<0.01), and coffee intake (p<0.05) proved to be significant risk factors in men. Whereas, menopausal status (p<0.01), BMI (p<0.01), herbal drug history (p<0.01), amount of food intake (p<0.05), waist circumference (p<0.05), and alcohol consumption (p<0.05) were significant risk factors in women. Conclusions : The significant risk factors, for both men and women, relating to the serum total cholesterol were waist circumference and BMI. Thus, for the reduction of serum total cholesterol level, it is recommended that health education for the control of obesity should be implemented.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.6
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• pp.755-764
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• 2016

Pressure retarded osmosis (PRO) processes can be implemented on a number of water types, using different technologies and achieving various power outcomes. In this study, Sewage facility effluent was used for feed solution of PRO and synthetic NaCl water for draw solution. This study was conducted to investigate effect of water quality of pretreatment on power density and flux decline in PRO process. The results show that organic and particulate foulants have to be removed for more stable operation. Flourescence technique with EEM enables to investigate the chemical properties of aquatic organic matter by extracting spectral information. Humic/fulvic matters and soluble microbial by-products were analyzed as the most affecting factors on the PRO performance. As a result of analyzing the whole system based on the energy consumption of the unit process, specific energy consumption(SEC) of the applicable technology for PRO pre-treatment should be about $0.2kWh/m^3$ or less.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.259-264
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• 2004

Baek-kimchi (whitish baechu kimchi) was evaluated for anti-obesity properties and effects on triglyceride (TG) and cholesterol in blood and adipose tissues in rats fed a high fat (20 %) diet, and compared to the similar effects of baechu kimchi. Baek-kimchi does not use red pepper powder but contains higher levels of sliced radish and pear than baechu kimchi. SD rats were raised for four weeks on either a normal diet (ND, based on the AIN-93M diet), high fat diet (HFD, supplemented with 16% lard oil in the ND), or HFD containing 5 % baek-kimchi or 5 % baechu kimchi. Feed consumption was not different among the groups, but weight gains were significantly lower in the groups fed either the normal diet or HFD with baek-kimchi or baechu kimchi diets than the group fed HFD alone. The weights of liver and epididymal and perirenal fat pads in baek-kimchi and baechu kimchi diet groups were lower than those of the HFD groups, but the baek-kimchi diet group had lower epididymal and perirenal fat pad weights than the baechu kimchi diet group (p<0.05). The baechu kimchi dietary group also had significantly lower triglyceride and cholesterol contents in liver and epididymal and perirenal fat, reversing the higher levels seen in HFD. Baek-kimchi and baechu kimchi diets were also effective in lowering serum triglyceride and cholesterol levels (p<0.05). These results suggest that baek-kimchi and baechu kimchi consumption can reverse the effects of HFD on weight gain and blood and tissue lipids, and that baek-kimchi is more effective than baechu kimchi. The greater effect is probably due to the higher content of radish and pear used in baek-kimchi.

• New & Renewable Energy
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• v.19 no.4
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• pp.35-45
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• 2023

Global efforts are focused on achieving carbon neutrality due to the increases in the levels of greenhouse gases. Moreover, the greenhouse gases generated from the disposal of municipal solid waste (MSW) are the primary sources of emissions in South Korea. In this study, we conducted the biological conversion of syngas (CO, H₂, and CO₂) generated from MSW gasification. The MSW-derived syngas was used as a feed source for cultivating Eubacterium limosum KIST612, and pressurization was employed to enhance gas solubility in culture broth. However, the pH of the medium decreased owing to the pressurization because of the CO₂ in the syngas and the cultivation-associated organic acid production. The replacement of conventional HEPES buffer with a phosphate buffer led to an approximately 2.5-fold increase in acetic acid concentration. Furthermore, compared with the control group, the pressurized reactor exhibited a maximum 8.28-fold increase in the CO consumption rate and a 3.8-fold increase in the H2 consumption rate.

• Journal of the Korean Society of Safety
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• v.39 no.1
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• pp.1-8
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• 2024

Commercial gas stoves feed primary air to the burner and burn the fuel-air mixture in a partially premixed combustion. This mechanism produces carbon monoxide during combustion. In this study, design parameters of a commercial gas stove were optimized by considering the carbon monoxide emission. Gas consumption rate, carbon monoxide emission, and water boiling temperature as a heating performance were determined. Carbon monoxide emission was measured using a Korean Industrial Standards standard collector. Water boiling temperature was measured by first soaking the pot in water for approximately 10 min and then heating the pot filled with water. A thermocouple was installed inside the pot. Carbon monoxide increased as the nozzle diameter was increased and the burner-pot height was decreased. This result was due to the insufficient mixing between the fuel and air. Heating performance was enhanced when the nozzle diameter was increased and the burner-pot height was decreased. However, the heating performance deteriorated when the nozzle diameter was 1.8 mm and the burner-pot height was reduced to 50 mm. This phenomenon was due to the formation of a flame on the side of the pot. A merit factor was defined to find the optimal design parameters to satisfy gas consumption rate, carbon monoxide emission, and heating performance. Optimal design values were established to be a nozzle diameter of 1.5 mm and a burner-pot height of 60 mm.

• Animal Bioscience
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• v.37 no.4_spc
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• pp.775-785
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• 2024

Pork production is a significant agricultural enterprise in the United States and Canada. The United States is the third-largest global producer of pork and Canada ranks seventh in pork production. The North American Free Trade Agreement and its successor, the U.S.-Mexico-Canada Agreement, have facilitated trade and integration between the two countries. The majority of production systems are modern and intensive, characterized by large vertically integrated farms using advanced technologies. Both nations benefit from their status as major producers of feed grains, with the United States leading in corn and soybeans, while Canada excels in canola and barley production. The regulatory frameworks for food safety, animal welfare, and environmental stewardship differ slightly, with the FDA and USDA overseeing these aspects in the United States, and Health Canada and the Canada Food Inspection Agency in Canada. The United States and Canada also have well-established distribution networks for pork products, relying on both domestic and international markets. Export markets play a crucial role, with the United States being a major importer of Canadian pigs, and both countries exploring opportunities in Asia. Despite a rise in global demand, domestic pork consumption trends differ, with per capita consumption remaining stable in the USA and declining in Canada. Changing consumer preferences, including a demand for ethically raised and locally sourced pork, may influence production practices. Future trends in pig production include a focus on consumer concerns, sustainability, disease prevention, reduction of antimicrobial use, and advancements in technology. The industry is adapting to challenges such as disease outbreaks and changing regulations, with a strong emphasis on animal welfare. Labor and workforce considerations, along with advancements in technology and automation, are expected to shape the efficiency of pork production in the future.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.4
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• pp.524-530
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• 2008

In this study, the effects of feed containing citrus byproducts on the physicochemical characteristics and palatability of Korean native chickens were investigated. The Korean native chickens used in this study were divided into two groups: T0 (chickens that were not fed citrus byproducts until they were 39 weeks old) and T1 (chickens that were fed citrus byproducts). The feed given to the T1 chickens was the same as that given to the T0 chickens for the first 16 weeks. Between weeks $17{\sim}39$, the feed given to the T1 chickens was prepared by adding 4% of the citrus byproducts to the feed given to the T0 chickens. The chickens used in the experiment were chilled for 2 days after being sacrificed. The feed containing citrus byproducts did not cause any statistically significant differences in the breast and thigh characteristics of lightness ($L^*$ value), redness ($a^*$ value), yellowness ($b^*$ value), water-holding capacity, frozen loss, thawing loss and boiling loss. As for the rheological properties, there was no statistically meaningful difference in the breast/thigh characteristics of springiness, cohesiveness, gumminess, and chewiness between the T0 and T1 chickens. However, hardness and shear force were significantly lower in the T1 chickens than in the T0 chickens (p<0.05). The acid and peroxide values were also lower in the T1 chickens than in the T0 chickens, but the difference was not statistically significant. Antioxidant activity was better in the T1 chickens than in the T0 chickens. Thus, the results of the present study show that consumption of citrus byproducts did not affect the color and smell of raw meat. The palatability of boiled meat was significantly better in the T1 chickens than in the T0 chickens.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.17-23
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• 2013

This work was carried out to investigate the performance of early laying period of large-type Korean native ducks. One hundred sixty eight ducks were used in this work and divided into A and B strains (6 replications/strain, 14 birds/replication). The days at first egg of A and B strains were the age of 154.5 and 154.7 days, egg weights were 69.1 g and 65.5 g, and body weights were 3,187 g and 3,105 g at the period of laying the first egg, respectively. The days at sexual maturity of A and B strains were the age of 175.8 and 171.5 days, egg weights were 75.2 g and 74.9 g, and body weights were 3,245 g and 3,225 g at the period of laying the first egg, respectively. There were no significant differences on the day of first egg, the day of sexual maturity, egg weight and body weight at first egg and the sexual maturity, average body weight, and daily feed intake between A and B strains (P>0.05). The day of the sexual maturity of B strain was earlier than that of A strain (P<0.05). However, weekly body weight was the highest at the age of 28 weeks (P<0.05), and weekly feed intake increased after 26 weeks old (P<0.05). Egg production (%) of B strain was higher than that of A strain at the age of 22~24 weeks (P<0.05), but there was no significant difference on egg production (%) the other weeks. A number of egg laid of B strain was higher than A strain at 22~24 weeks old (P<0.05). Feed conversion ratio of A and B strains were 10.7 and 6.53 at 24~24 weeks old, respectively, so feed conversion ratio of A strain was higher than that of B strain (P<0.05). Weekly feed conversion ratio wes the highest at 20~22 weeks old, and significantly decreased until 24~24 weeks old, but were lowly maintained from the age of 24 weeks to the age of 30 weeks. These results provided the basic data on the record of early laying period of large-type Korean native ducks.