• Korean Journal of Poultry Science
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• v.29 no.3
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• pp.195-204
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• 2002

Two experiments were conducted to study the effects of nutrient level and feeding method of split diets for a.m. and p.m. on laying hen performance, feed cost and eggshell quality. In experiment 1, 384 ISA Brown layers of 30∼38wk of age were assigned to four treatments which comprise of three replicates each containing 32 birds. The control(C) was fed a conventional single diet throughout the day and split diet groups(T1, T2 and T3) were offered high energy/protein-low Ca diets, and low energy/protein-high Ca diets in a.m.(04:00∼15:00) and p.m.(15:00∼21:00), respectively. In the split diet groups, daily ME and CP consumption, and feed cost were significantly reduced(P<0.05) compared to the C, while the hen-day egg production, average egg weight and daily feed intake were not different among treatments. Due to the reduced daily ME and CP intakes and feed cost, the conversions of feed, ME, CP and feed cost required per day and per kg egg mass were also significantly improved(P<0.05) in the split diet groups. Eggshell qualities (egg specific gravity, egg breaking strength and eggshell thickness) were improved(P<0.05) by split diet feeding. As the Ca level of the p.m. diet increased. In Experiment 2, 384 ISA Brown layers of 50∼58 wk of age were used in three treatments and each treatment was represented by four replicates each containing 32 birds. The control(C) was fed a conventional single diet throughout the day and split diet group(T1) was offered high energy/protein-low Ca diets, and low energy/protein-high Ca diets in a.m.(04:00∼l5:00) and p.m.(15:00∼21:00), respectively. T2 group was fed the diet mixed (50:50) with the a.m. diets in mash and p.m. diet in pellet used T1 group. In T1 and T2 groups, daily feed intake and average egg weight were significantly reduced(P<0.05) compared to the C, while the hen-day egg production was not influenced by the feeding system. Daily ME and CP consumption, and feed cost were reduced(p.0.05), and the conversions of ME, CP and feed cost required per egg were also significantly improved(P<0.05) in T1 and T2, while the conversions of feed, ME, CP and feed cost required per kg egg mass were not different to the C. Eggshell qualities of T1 and T2 were improved(P<0.05) compared to the others. It was concluded the feed and nutrients consumption, feed cost per day or per kg egg mass could be reduced by introducing split diets for a.m. and p.m. and the feeding method of mixed diet of split diets were also convenient and effective for sparing feed cost and improvement of eggshell quality.

• Fire Science and Engineering
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• v.24 no.3
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• pp.33-38
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• 2010

Recently commercial egress softwares are frequently used for the risk assessment. The estimation of evacuation time is an important procedure and the outflow coefficient in a bottleneck becomes the crucial factor for design of emergency planning. This paper compares the outflow coefficient of measurement with those of softwares in the bottlenecks of subway stations where masses of people movement is observed. Stairway and turnstile are the 2 bottleneck points along escape pathway. For the escape simulation it is recommended that 2 different modes be used in the programs for 2 kinds of bottleneck. The results of the comparison makes a big difference among them and some of differences can be reduced by correct design of input data. In conclusion the results of simulation should be examined thoroughly by procedure of comparisons with other results.

• Journal of Practical Agriculture & Fisheries Research
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• v.18 no.1
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• pp.13-24
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• 2016

Sixty Hanwoo steers(15 months of age; 409±29.2 kg of BW) were used to evaluate the effects of dietary vitamins A and D restriction on carcass characteristics. Steers were allotted randomly to 1 of 4 treatments: Control(diet supplemented with vitamins A, D and E), -A (diet supplemented with vitamins D and E), -D(diet supplemented with vitamins A and E) and -AD(diet supplemented with vitamin E only). Steers were fed the experimental diet for a period of 8 months(until 23 months of age), and then supplemented with vitamins A and D at 0.05% of the diet(as fed-basis) from 24 to 26 months of age, and at 0.1% of the diet from 27 to 31 months of age(harvesting time). Dietary restriction of vitamins A and D did not affect DM intake, daily gain and feed conversion ratio. But the concentration of serum retinol was significantly(P<0.05) decreased by vitamin A restriction with the lowest concentration being seen at 23 months of age(345.0 ㎍/L and 326.7㎍/L for control and -D treatment versus 169.3 ㎍/L and 175.4 ㎍/L for -A and -AD treatments). The serum concentration of 25(OH)D₃ was also decreased significantly(P<0.05) by vitamin D restriction and the lowest concentration was seen at 18 months of age(53.7ng/ml and 61.8ng/ml for control and - A treatment versus 24.0 ng/ml and 24.5 ng/ml for -D and -AD treatments). After the restriction period of vitamins A and D, the concentrations of retinol and 25(OH)D₃ for - A, -D and -AD treatments were recovered at those of control. Dietary restriction of vitamins A and D did not affect carcass weight, backfat thickness, ribeye area, quality grade and yield grade. But marbling score was significantly increased by vitamin A restriction compared with control(6.73, 6.87 and 5.73 for -A, -AD and control, respectively). The results of the present study suggested that dietary vitamin A restriction could improve marbling score in Hanwoo steers.

• Journal of Wetlands Research
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• v.14 no.2
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• pp.169-180
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• 2012

Aster altaicus var. uchiyamae, endangered plants to grade II designated by the Ministry of Environment Korea, is only distributed in Gyeongsangbukdo, Chungcheongnamdo in Korea. In order to know the effects of elevated $CO_2$ concentration and temperature on ecological responses of A. altaicus var. uchiyamae, this study was carried out in the control(ambient $CO_2$ + ambient temperature) and treatment(elevated $CO_2$ + elevated temperature) at glasshouse. As a result, germination rate of A. altaicus var. uchiyamae was higher in control than in treatment. Period of alive leaf was longer in control than in treatment. Period of blooming and seed maturity was faster in control than in treatment. Shoot and root weight were heavier in control than in treatment. No. of inflorescence per plant and seed per inflorescence was higher in control than in treatment. Weight of inflorescence per plant, seed per inflorescence and one seed was heavier in control than in treatment. These results indicate that ecological responses of A. altaicus var. uchiyamae may be more negatively affected by elevated $CO_2$ and temperature except for phenological responses of that may be delayed under future global warming situation.

• Horticultural Science & Technology
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• v.17 no.5
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• pp.578-580
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• 1999

The effects of the orchid mycorrhizal fungi isolated from Cymbidium goeringii were investigated on the growth of orchid plants. The plants, a hybrid of Cymbidium kanran Jeju${\times}$C. kanran Nangoku and Phalaenopsis were inoculated with the fungal isolates of Rhizoctonia repens (P1), R. endophytica (P2) and R. repens (P3; different from P1) on the oatmeal agars for two months. Then the orchid plants were cultivated in the greenhouse for eighteen months. The difference of plant growth after cocultivation for two months was not found among the treatments. After cultivation for four months, the growth of hybrid plants of Cymbidium kanran Jeju${\times}$C. kanran Nangoku was observed to be distinguished in the Rhizoctonia repens (P1). After cultivation in the greenhouse for eighteen months, the plant height, the number of shoots, the number of leaves, the number of roots and plant fresh weight of the hybrid of Cymbidium kanran Jeju${\times}$C. kanran Nangoku, inoculated with Rhizoctonia repens (P1), were significantly increased compared to those of the control. The plants inoculated with Rhizoctonia repens (P3) were not different and the plants inoculated with R. endophytica were poor compared to the control. The plant height and fresh weight of the Phalaenopsis, inoculated with Rhizoctonia repens (P1), increased significantly compared to those of the control. Overall, Rhizoctonia repens (P1), was the most effective for the growth of a hybrid of Cymbidium kanran Jeju${\times}$C. kanran Nangoku.

• Korean Journal of Optics and Photonics
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• v.35 no.2
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• pp.61-70
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• 2024

We demonstrate a laser power meter calibration system based on 12-diode laser sources coupled to single-mode fibres in a wavelength range from 400 to 1,600 nm. In our system, three laser power controllers ensure that the output power uncertainty of all laser sources is less than 0.1% (k=2). In addition, all laser beams are adjusted to have similar beam sizes of approximately 2 mm (1/e²-width) at the measurement position to minimise unmeasured laser power on a detector. As a reference detector, we use an integrating sphere combined with silicon and indium gallium arsenide photodiodes to minimise the non-uniformity and non-linearity of responsivity. The minimum uncertainty of the calibration system is estimated to be 1.1% (k=2) for most laser wavelengths.

• Korean Journal of Environment and Ecology
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• v.10 no.2
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• pp.270-282
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• 1997

This investgation was performed to provide basic data for the management program of the Soraksan national park. Sixty plots were set up and surveyed in the Sinhungsa-Wasondae Area. The vegetation was divided into two communities, Pinus densiflora community and Quercus serrata community, according to the analysis of DCA ordination. It was found out that the succession of the Pinus densiflora comunity would proceed to Quercus serrata community of which components was dominant in understory layer and shrub layer. And it was found out that in the Quercus serrata community the Pinus densiflora being mainly big size in DBH would becomr dominant comtinuously. Shannon's diversity of both community were 1.2554 and 1.1134 respectively. The numbers of woody species per 100m$^{2}$ ranged 7 to 26, and the average number of woody species was 13.

• Korean Journal of Environment and Ecology
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• v.16 no.4
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• pp.433-440
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• 2003

A vegetation structure by attitudinal changes from Jeongryongchi to Gogiri section of Baekdudaegan were investigated by sample plots(nine 500$m^2$). Using TWINSPAN and DCA techniques, vegetation structure was analyzed. In the results from the analysis of both techniques, Quercus mongolica is dominant species and attitudinal zonations were divided into 2 groups such as above 900m area and lower one by subspecies in subtree and shrub layers. Similarity index analyses of elevational ranges showed discontinuities between above and lower elevation area. In the analysis of species diversity, there was no significant difference due to altitude.

• Korean Journal of Poultry Science
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• v.30 no.3
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• pp.203-209
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• 2003

This experiment was conducted to investigate the influence of dietary supplementation of two different types of multiple probiotics in broiler chicks. Four hundred one day old male broiler chicks(Ross ${\times}$ Ross) were raised in the floor pen with five treatments(0, A: 0.10, 0.20%, B: 0.10, 0.20% of probiotics), consisting of 5 replicates for 5 weeks. Weight gain, feed intake and feed conversion were measured weekly, Total Lactobacillus, yeast, E. coli, Salmonella were examined from ileum and cecum at the end of experiment. Sera protein, cholesterol and ND vaccine titer were measured and fecal COD, CO$_2$ and NH$_3$ were detected in 24 hours after collection. Weight gain of chickes fed both types of probiotics increased for the first three weeks and showed significantly higher for the rest two weeks. Feed intake tended to be high in probiotics treatments compared with contro(P<0.05)1. Feed conversion improved significantly in B types of 0.2% probiotics compared with control. Total number of Salmonella was not consistent in ileum among treatments, whereas E. coli tended to be decreased in both types of probiotics compared with control. NH$_3$ and CO$_2$ emission of feces were decreased in both types of probiotics, but it was not statistically different(p>0.05). COD of chicks fed both probiotics was lower than control. There were no significantly different breast meat(P>0.05). Total cholesterol decreased in probiotics groups regardless of it's type. ND antibody vaccine titer was prone to be a small increments.

• Korean Journal of Poultry Science
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• v.37 no.4
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• pp.323-329
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• 2010

The objective of this study was to investigate the effects of supplementation diets with Kalopanax pictus leaf powder on performance, proximate composition, carcass characteristics and blood characteristics of chicken meat. Broiler chicks were fed diets containing Kalopanax pictus leaves with concentration of 0% (Control), 0.5% (T1), 1.0% (T2), and 2.0% (T3) for five weeks. There were no significant differences in performance among treatment, however there were significant decrease in mortality within treatment. The crude fat of chicken meat was increased in diets by addition of Kalopanax pictus leaf powder than control, but moisture, crude protein, and crude ash were no significant differences. The abdominal fat was significantly increased by the supplementation of Kalopanax pictus leaf powder compare to the control (P<0.05). The total cholesterol, LDL-cholesterol and triglyceride of control were higher than treatment groups, and the HDL-cholesterol and glucose of control were lower than treatment groups (P<0.05). Especially, T2 and T3 were significantly (P<0.05) more effective in improving cholesterol compare to other treatment groups. In conclusion, these data indicate that supplementation of 1.0% Kalopanax pictus leaf powder (T2) were most effective in decreasing total cholesterol, LDL-cholesterol and triglyceride and increasing HDL-cholesterol.