• 한국ITS학회:학술대회논문집
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• 2010.05a
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• pp.33-36
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• 2010

• International Journal of Automotive Technology
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• v.7 no.3
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• pp.295-301
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• 2006

A new combustion method of high compression ratio SI engine was studied and proposed in order to achieve high thermal efficiency, comparable to that of CI engine. Compression ratio of SI engine is generally restricted by the knocking phenomena. A combustion chamber profile and a cranking mechanism were studied to avoid knocking with high compression ratio. Because reducing the end-gas temperature will suppress knocking, a combustion chamber was considered to have a wide surface at the end-gas region. However, wide surface will lead to large heat loss, which may cancel the gain of higher compression ratio operation. Thereby, a special cranking mechanism was adapted which allowed the piston to move rapidly near TDC. Numerical simulations were performed to optimize the cranking mechanism for achieving high thermal efficiency. An elliptic gear system and a leaf-shape gear system were employed in numerical simulations. Livengood-Wu integral, which is widely used to judge knocking occurrence, was calculated to verify the effect for the new concept. As a result, this concept can be operated at compression ratio of fourteen using a regular gasoline. A new single cylinder engine with compression ratio of twelve and TGV(Tumble Generation Valve) to enhance the turbulence and combustion speed was designed and built for proving its performance. The test results verified the predictions. Thermal efficiency was improve over 10% with compression ratio of twelve compared to an original engine with compression ratio of ten when strong turbulence was generated using TGV, leading to a fast combustion speed and reduced heat loss.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.4
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• pp.583-589
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• 1994

In order to study the interrelationships of calcium (0.45 vs. 0.90%), phosphorus (0.40 vs. 0.70%) and protein (17, 20, 23%), $2{\times}2{\times}3$ factorial design was employed. A total of 480 broilers (Hisex-Hibro) aged 3 days were fed the experimental diets for a period of 28 days. Body weight gain, daily feed intake and feed efficiency were investigated for the simple effects, first order interaction and second order interaction of the dietary factors. These effects were also applied to bone ash retention, percent Ca in bone & ash, percent P in bone & ash, and protein utilizability. Results were as follows. 1) For body weight gain, simple effects of dietary levels of Ca, P, CP were found to be significant (p<0.05). Body weight gain at 0.90% Ca level was improved as the dietary CP levels increased. For the feed intake, single effects of dietary levels of both P and CP were found (p<0.05). Feed efficiency was improved as the dietary CP and P levels increased. Ca $\times$ P interaction was found to be significant for body weight gain, feed intake and feed efficiency (p<0.05), however, Ca $\times$ P $\times$ CP interaction effect was not found. 2) Protein utilizability decreased as the dietary CP level increased (p<0.01). 3) 0.90% Ca in diet showed less bone ash retention than 0.45% Ca level. And, increasing the dietary P level resulted in increased bone ash retention. Increasing the dietary P level resulted in increased bone Ca retention (p<0.01) and increased bone P retention (p<0.05). Dietary CP levels had significant (p<0.01) effect on bone Ca retention except for 23% CP level. Increasing the dietary Ca level resulted in wider Ca:P ratio of bone, but increasing the dietary P level resulted in narrower Ca:P ratio of bone. 4. Ca $\times$ P interaction effects were found to be significant (p<0.01) for bone ash, bone Ca & P, ash P content, and bone Ca:P ratio. Ca $\times$ P $\times$ CP interaction effects were found for bone ash (p<0.01), bone Ca (p<0.05) and bone P content (p<0.01).

• The Korea Journal of Herbology
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• v.29 no.1
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• pp.35-43
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• 2014

Objectives : We investigated the effects of gambigyeongsinhwan(GGH)(1) on body weight and non-alcoholic fatty liver disease(NAFLD) examined whether blood total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels and hepatic lipid accumulation are inhibited by it in high fat diet-fed obese male mice. Methods : 8 weeks old, high fat diet-fed obese male mice were divided into 5 groups: C57BL/6N normal, control, GGH(1)-1, GGH(1)-2 and GGH(1)-3. After mice were treated with GGH(1) for 8 weeks, we measured body weight gain, food intake, feeding efficiency ratio, fat weight, plasma ALT, leptin and lipid levels. We also did histological analysis for liver and fat on the mice. Results : Compared with controls, GGH(1)-treated mice had lower body weight gain and adipose tissue weight, the magnitudes of which were prominent in GGH(1)-3. Compared with controls, GGH(1)-treated mice had lower feeding efficiency ratio and blood leptin level, the magnitudes of which was prominent in GGH(1)-3. Compared with controls, GGH(1)-treated mice had lower blood plasma total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels. Compared with controls, GGH(1)-3 treated mice had lower blood plasma ALT concentration. Consistent with their effects on body weight gain, the size of adipocytes were significantly decreased by GGH(1), whereas the adipocyte number per unit area was significantly increased, suggesting that GGH(1) decreased the number of large adipocytes. Hepatic lipid accumulation was decreased by GGH(1). Conclusions : In conclusion, these results suggest that GGH(1) exhibits anti-obesity effects through the modulation of feeding efficiency ratio and plasma obesity parameters. Moreover, it seems that GGH(1) also contributes to improve NAFLD through the regulation of plasma ALT and hepatic triglyceride accumulation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.1
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• pp.99-106
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• 2013

We investigated the effects of gambigyeongsinhwan(GGH)(4) on body weight and non-alcoholic fatty liver disease(NAFLD) examined whether blood total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels and hepatic lipid accumulation are inhibited by it in high fat diet-fed obese male mice. 8 weeks old, high fat diet-fed obese male mice were divided into 5 groups: C57BL/6N normal, control, GGH(4)-1, GGH(4)-2 and GGH(4)-3. After mice were treated with GGH(4) for 8 weeks, we measured body weight gain, food intake, feeding efficiency ratio, fat weight, plasma ALT, leptin and lipid levels. We also did histological analysis for liver and fat on the mice. Compared with controls, GGH(4)-treated mice had lower body weight gain and adipose tissue weight, the magnitudes of which were prominent in GGH(4)-2. Compared with controls, GGH(4)-treated mice had lower feeding efficiency ratio and blood leptin level, the magnitudes of which was prominent in GGH(4)-2. Compared with controls, GGH(4)-treated mice had lower blood plasma total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels. Compared with controls, GGH(4)-2 treated mice had lower blood plasma ALT concentration. Consistent with their effects on body weight gain, the size of adipocytes were significantly decreased by GGH(4), whereas the adipocyte number per unit area was significantly increased, suggesting that GGH(4) decreased the number of large adipocytes. Hepatic lipid accumulation was decreased by GGH(4). In conclusion, these results suggest that GGH(4) exhibits anti-obesity effects through the modulation of feeding efficiency ratio and plasma obesity parameters. Moreover, it seems that GGH(4) also contributes to improve NAFLD through the regulation of plasma ALT and hepatic triglyceride accumulation.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.2
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• pp.185-191
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• 1998

A total of 240 weaned pigs (BW 5.4 kg) were allotted in a completely randomized block design to find out the optimum lactose : sucrose ratio for the weaned pigs. Treatments were 100:0 (A), 75:25 (B), 50:50 (C), 25:75 (D) and 0:100 (E) in lactose : sucrose ratio. For the first week after weaning, average daily gain (ADG) and feed/gain (F/G) were improved (p < 0.05) for pigs fed A, B and C diets compared to pigs fed diets D and E, but the average daily feed intakes (ADFI) of the pigs were not different. From d 7 to 14, no significant differences was found in ADG and ADFI among the treatments, but pigs fed the diets A, B and C had improved F/G compared with the pigs fed diets D and E (p < 0.05). From d 15 to 21, no significant differences were found in ADG, ADFI and F/G among the treatments. The digestibility of nutrients was not influenced by the lactose : sucrose ratio except nitrogen. Nitrogen digestibility of A diet was significantly higher than D and E diets (p < 0.05) but no significant differences were found among diets A, B and C. Dry matter and phosphorus excretions were not influenced by the treatments. The pigs fed diets A, B and C excreted significantly less nitrogen than the pigs fed diets D and E. In conclusion, the results suggest that sucrose can effectively replace up to 50% lactose in starter diets.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.70-73
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• 2012

In this paper, we introduce a design method for a quasi-Yagi antenna (QYA) with broadband characteristics of an impedance bandwidth ratio of > 2 : 1 and a gain of > 4 dBi. The QYA is fed by a microstrip line fabricated on a coplanar strip line and it consists of 3 elements; a planar dipole, a nearby director close to the dipole, and a ground plane reflector. By placing a rectangular patch-type director with large width near to the dipole driver, broadband characteristics are achieved. An optimized 3-element QYA for operation over 1.6-3.5 GHz (bandwidth ratio 2.2 : 1) is fabricated on an FR4 substrate with a size of $90mm{\times}90mm$ and tested experimentally. The results show an impedance bandwidth of 1.56-3.74 GHz (bandwidth ratio 2.4 : 1) for VSWR < 2, a peak gain of 4.41-6.53 dBi, and a front-to-back ratio (FBR) > 13.6 dB within the bandwidth.

• Journal of Aquaculture
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• v.19 no.2
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• pp.95-98
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• 2006

This study was performed to determine possibility of compensatory growth of juvenile olive flounder fed a commercial feed during the summer season. Five treatments of fish with triplicates were prepared: C, S1, S2, S3 and S4. Fish in the control group (C) was hand-fed with the commercial feed to apparent satiation twice daily for 6 days a week during 6 weeks. Fish in S1, S2, S3, and S4 experienced 1, 2, 3, and 4 weeks of starvation before fed to satiation twice daily for 5, 4, 3, and 2 weeks, respectively. The feeding trial lasted far 6 weeks. Survival of flounder in C, S1 and S2 was significantly (P<0.05) higher than that offish in S4. Weight gain and specific growth rate (SGR) of flounder in C and S1 were significantly (P<0.05) higher than those of fish in S2, S3 or S4. And weight gain and SGR of flounder in S2 and S3 were significantly (P<0.05) higher than those of fish in S4. Feed consumption of flounder tended to increase with weeks of feeding. Feed efficiency ratio and protein efficiency ratio for flounder in C, S1, S2 and S3 were significantly (P<0.05) higher than those for fish in S4. Moisture content of the whole fish in C was lowest, but highest for fish in S4, respectively. Crude protein content of the whole fish in C was highest, but lowest far fish in S4, respectively. Crude lipid content of the whole fish in C, S1 and S2 was significantly (P<0.05) higher than that of fish in S4. In conclusion, full compensatory growth was obtained in juvenile olive flounder fed for 5 weeks after 1-week feed deprivation during the summer season. Compensatory growth of fish was well supported by improvement in feed efficiency ratio and protein efficiency ratio.

• Journal of Food Hygiene and Safety
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• v.14 no.2
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• pp.195-200
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• 1999

The present study has been undertaken to investigate the effects of crude ginseng extract added to food on the lipid composition in serum of rats fed lard and alcohol. Thirty-five males of Sprague-Dawley strains weighed about 130 g were divided into 7 group, each group receiving a different diet for 10 weeks ; i.e. basal diet plus 15% lard, basal diet plus 5% alcohol, basal diet plus 0.5% crude ginseng extract, basal diet plus 15% lard and 0.5% crude ginseng extract. Determinations were carried out on the net weight gain, food efficiency ratio, weight of organs, triglyceride, total cholesterol, HDL-cholesterol, free cholesterol. The results obtained were as follows : 1. Rats given feed containing lard and alcohol showed significant decrease in net weight gain, but crude ginseng extract caused an increase in food efficiency ratio. 2. Lard supplementation group showed increase in the weight of liver, kidney, spleen, but another groups did not. 3. The contents ratio of triglyceride, total cholesterol in serum of lard-fed group showed significant increase compared to controls and but the simultaneous supplementation of crude ginseng extract and lard decreased significantly than those of lard-fed group. 4. The contents of free-cholesterol and ester cholesterol in serum of the simultaneous supplementation of crude ginseng extract group decreased as compared with the lard single fed group. 5. Crude ginseng extract single-fed groups. 6. The ratio of contents of VLDL, LDL-cholesterol in serum was significantly high in the only lard containing group and alcohol group, the crude ginseng extract supplemented group was showed lower tendency than only lard and alcohol group. The above results suggest that crude ginseng extract would prevent the metabolic disease by improving hyperlipoidemia.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11A
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• pp.862-869
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• 2009

We propose a new adaptive K-best Sphere Decoding (SD) algorithm for Multiple Input Multiple Output (MIMO) systems where the number of survivor paths, K is changed based on the characteristics of path metrics which contain the instantaneous channel condition. In order to overcome a major drawback of Maximum Likelihood Detection (MLD) which exponentially increases the computational complexity with the number of transmit antennas, the conventional adaptive K-best SD algorithms which achieve near to MLD performance have been proposed. However, they still have redundant computation complexity since they only employ the channel fading gain as a channel condition indicator without instantaneous Signal to Noise Ratio (SNR) information. hi order to complement this drawback, the proposed algorithm use the characteristics of path metrics as a simple channel indicator. It is found that the ratio of the minimum path metric to the other path metrics reflects SNR information as well as channel fading gain. By adaptively changing K based on this ratio, the proposed algorithm more effectively reduce the computation complexity compared to the conventional K-best algorithms which achieve same performance.