• 상하수도학회지
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• 제12권3호
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• pp.107-117
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• 1998

In order to removal turbidity at high turbidity, this study was carried to evaluate the coagulants(Alum, PACl, PACS) that was suited the characteristics of raw water in water treatment plants and to determinate the optimum method of lime feed. When the optimum coagulant was selected the organic matter removal was also investigated as $UV_{254}$. PACl, lime first feed had the highest turbidity removal efficiency rate as above 99.1% and then $UV_{254}$ removal rate was obtained over than 88.0%. If you had the necessary of the lime feed, among the method of lime feed time interval feed largely was improved than simultaneous feed. Also, lime feed dose had about 1/5 of coagulants dose in case of Alum and PACl, but always PACS should be considerated lime dose.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1295-1300
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• 2009

A 2,172-bp full-length gene (aga-F78), encoding a protease-resistant $\alpha$-galactosidase, was cloned from Rhizopus sp. F78 and expressed in Escherichia coli. The deduced amino acid sequence shared highest identity (45.0%) with an $\alpha$-galactosidase of glycoside hydrolase family 36 from Absidia corymbifera. After one-step purification with a Ni-NTA chelating column, the recombinant Aga-F78 migrated as a single band of ~82 and ~210 kDa on SDS-PAGE and nondenaturing gradient PAGE, respectively, indicating that the native structure of the recombinant Aga-F78 was a trimer. Exhibiting the similar properties as the authentic protein, purified recombinant Aga-F78 was optimally active at $50^{\circ}C$ and pH 4.8, highly pH stable over the pH range 5.0-10.0, more resistant to some cations and proteases, and had wide substrate specificity (pNPG, melidiose, raffinose, and stachyose). The recombinant enzyme also showed good hydrolytic ability to soybean meal, releasing galactose of $415.58\;{\mu}g/g$ soybean meal. When combined with trypsin, the enzyme retained over 90% degradability to soybean meal. These favorable properties make Aga-F78 a potential candidate for applications in the food and feed industries.

• 한국버섯학회지
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• 제17권2호
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• pp.47-51
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• 2019

Our research on juvenile Oncorhynchus masou masou in oyster mushroom supplemented diet was studied to investigate the effect of feeding. Mixing of feed ingredients for dried oyster mushrooms, 3.5, 7.0, 10.5, 14.0 (%) was added to the amount of oyster mushroom dietary beta-glucan content of the more abundant. After the weight of feed given to salmon survey oyster mushrooms diet for 3.5 to 7.0% was similar to the formula feed and the weight of the fish ate oyster mushroom feed over 10.5% were reduced. The oyster mushroom of the experimental diets containing 3.5 to 7.0 percent hepatosomatic index and feed coefficient figure was similar to those of the formulated diets. Therefore we have juvenile cherry salmon fed diets containing 3.5 to 7.0% was considered good to eat and additional research on the immune response will be carried out was necessary.

• Fisheries and Aquatic Sciences
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• 제14권1호
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• pp.11-15
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• 2011

We examined the effects of 17${\alpha}$-methyltestosterone (MT) on growth and induced sex change in the longtooth grouper Epinephelus bruneus. The growth rate for body weight (GRW) and specific growth rate (SGR) of the group injected with MT over 8 weeks were significantly higher than those of the sham-injected control group, the group injected over 4 weeks, and the control group. Of the orally administrated groups, the GRWs of the control group and the group given 1 kg of feed with 2.0 mg of MT were highest and did not significantly differ from one another. For SGR, the treatment groups differed significantly, and the SGR of the control group was higher than those of the other groups (P<0.05). The condition factor (CF) of the group injected over 4 weeks was higher than those injected over 8 weeks, the sham-injected control group over 8 weeks, and the control group. The CF did not significantly differ between the sham-injected control group over 8 weeks and the injected group over 8 weeks, but these two groups differed from the control group (P<0.05). The CFs of the groups given 1 kg of feed with 0.5, 1.0, and 2.0 mg of MT were significantly higher than that of the control group (P<0.05). The feed efficiency ratio was not significantly affected by MT administration. Most of the experimental groups receiving MT developed many unidentified germ cell cysts and perinucleolus oocytes, although neither spermazoa cells nor sex-changed males were observed in any of the treatments.

• Asian-Australasian Journal of Animal Sciences
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• 제18권1호
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• pp.32-37
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• 2005

Under a typical Mediterranean environment in southern Australia, the evaporation rate increases significantly in hot summers, resulting in highly saline drinking water for grazing animals. Also in the cropping areas, dryland salinity is a problem. Grazing animals under these environments can ingest excessive amount of salt from feed, drinking water and soil, which can lead to a reduction in growth rate. To understand the impact of high salt intake on grazing deer, two experiments were conducted to assess the effect of salt levels in drinking water on feed intake and growth rate of red and fallow weaner deer. The results revealed that fallow deer did not show any abnormal behaviour or sickness when salt level in drinking water was increased from 0% to 2.5%. Feed intake was not affected until the salt content in water exceeded 1.5%. Body weight gain was not affected by 1.2% salt in drinking water, but was reduced as salt content in water increased. Compared with deer on fresh water, the feed intake of red deer on saline water was 11-13% lower when salt level in drinking water was 0.4-0.8%. An increase in salt level in water up to 1% resulted in about a 30% reduction in feed intake (p<0.01). Body weight gain was significantly (p=0.004) reduced when salt level reached 1.2%. The deer on 1% salt tended to have a higher (p=0.052) osmotic pressure in serum. The concentration of P, K, Mg and S in serum was affected when salt level in water was over 1.0%. The results suggested that the salt level in drinking water should be lower than 1.2% for fallow weaner deer and 0.8% for red weaner deer to avoid any reduction in feed intake. Deer farmers need to regularly test the salt levels in drinking water on their farms to ensure that the salt intake of grazing deer is not over the levels that deer can tolerate.

• 농업과학연구
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• 제39권3호
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• pp.365-369
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• 2012

Fast recovery of feed intake and milk production are very important in the management of lactating sows because they are directly related to sow and litter performance. It is also known that parity is one of factors affecting feed intake and milk yield during lactation. Therefore, the objective of this study was to evaluate effects of different parities on productive performance of lactating sows fed diets containing different levels of DDGS. A total of 245 sows were divided into 3 parity groups of 1 to 2, 3 to 5, and over 5 parities. Within each parity group, sows were allottedto 1 of 4 dietary treatments that were prepared by inclusion of 0, 10, 20, and 30% DDGS in lactation diets. Diets were fed to sows during lactation. Sows with parities 1-2 had lower (p < 0.05) initial sow body weight, sow feed intake, sow weight change, and sow backfat change during lactation than sows with parities 3-5 as well as parities over 5. However, sows with parities over 5 had lower (p < 0.05) litter size at weaning, litter birth weight, litter weaning weight, and piglet average daily gain and higher pre-weaning mortality than sows with parities 1-2 as well as parities 3-5. In conclusion, parity influences productive performance of lactating sows.

• Asian-Australasian Journal of Animal Sciences
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• 제7권3호
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• pp.441-448
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• 1994

Postweaning performance data were obtained on 187 group fed purebred Angus calves from 12 selected sires (six high and six low feed conversion sires) in 1985 and 1986. The objective of this portion of the study was to develop prediction equations for feed conversion from a stepwise regression analysis. Variables measured were on-test weight (ONTSTWT), on-test age (ONTSTAG), five weights by 28-d periods, seven linear body measurements: heart girth (HG), hip height (HH), head width (HDW), head length (HDL), muzzle circumference (MC), length between hooks and pins (HOPIN) and length between shoulder and hooks (SHHO), and backfat thickness (BF). Stepwise regressions for maintenance adjusted feed conversion (ADJFC) and unadjusted feed conversion (UNADFC) over the first 140 d of the test, and total feed conversion (FC) until progeny reached 8.89 mm of back fat were obtained separately by conversion groups and sexes and for combined feed conversion groups and sexes. In general, weights were more important than linear body measurements in prediction of feed utilization. To some extent this was expected as weight is related directly to gain which is a component of feed conversion. Weight at 112 d was the most important variable in prediction of feed conversion when data from both feed conversion groups and sexes were combined. Weights at 84 and 140 d were important variables in prediction of UNADFC and FC, respectively, of bulls. ONTSTWT and weight at 140 d had the highest standardized partial regression coefficients for UNADFC and ADJFC, respectively, of heifers. Results indicated that linear measurements, such as MC, HDL and HOPIN, are useful in prediction of feed conversion when feed in takes are unavailable.

• 한국위성정보통신학회논문지
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• 제1권1호
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• pp.54-58
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• 2006

동작주파수를 쉽게 조절할 수 있는 신호생성용 안테나 (Antenna-Integrated Oscillator) 설계방법을 소개한다. 제안하는 회로는 광대역에서 부성저항을 갖는 능동회로 (Negative-Resistance Circuit)와 패치안테나로 구분되며, 오실레이터의 동작주파수는 안테나의 공진 주파수로 결정된다. 이러한 디자인 방법은 안테나와 오실레이터의 동작주파수 불일치로 인한 출력파워의 감소 가능성을 줄일 수 있다. 또, 제안하는 설계방법에서 안테나의 Feed 지점과 Feed 라인의 길이를 조절하여 최적의 출력파워를 낼 수 있음을 Load-Pull 시뮬레이션으로 확인하였다. C-band, X-band 회로를 각각 제작, 측정하였고 이를 통하여 설계방법의 타당성을 증명하였다.

• ETRI Journal
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• 제36권6호
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• pp.889-893
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• 2014

This paper presents a high-performance dual-circularly polarized feed employing a dielectric-filled circular waveguide. Novel features are incorporated in the proposed feed, such as a dielectric rod radiator for high gain and good impedance matching; dual quarter-wave chokes for low axial ratio over wide angles and for low back radiation; an integrated septum polarizer; and two end-launch-type coaxial-to-waveguide transitions. The proposed feed shows excellent performance at 5.0 GHz to 5.2 GHz.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.17-18
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• 2003

Although flounder is one of the most important marine fish for aquaculture in Korea, feeding the flounder in commercial farms depends mainly on moist pellet in which over 70% frozen fishes (e.g. frozen horse mackerel) are incorporated in its formulation. Therefore, for further expansion of flounder farming, it is essential to employ practical formulated feeds that can support reasonable growth. Development of nutritionally balanced and cost-effective feeds is dependant on the information about nutritional requirement and feed utilization of the species. Nutrient and energy source in feed are needed for the growth and maintenance of fish. Protein is probably the most important nutrient affecting fish growth and feed cost. Therefore, it is essential to determine the optimum dietary protein level for the growth of fish, both its high proportion in the feed and because it is the main factor in determining feed cost. Dietary energy level is also critical because protein source in the feed is utilized as an energy source when the feed deficient in energy is fed to fish, whereas when the feed excess in energy is fed to fish, feed consumption decreased and resulted in growth reduction due to lack of other necessary nutrients for normal growth. Improper dietary protein, energy levels and/or their ratio will lead to an increase of fish production cost and deterioration of water quality resulting from wasted feed; thus, they are important in formulating commercial feed. Dietary lipids play important roles in providing energy and essential fatty acid for normal growth and survival of fish. Although carbohydrates are not essential nutrients for carnivorous fish, these compounds play important roles as a low-cost energy source for protein sparing and also as a feed binder. Nutrition researches for flounder have identified its requirements of protein, lipid and essential fatty acid, vitamin, and minerals for normal growth. Other studies have also been carried out to investigate the utilization of the protein, lipid and carbohydrate sources. Based on these nutritional information obtained, practical feed formulations have been studied for improve aquaculture production of flounder. The results of the researches on utilization of dietary protein, lipid and carbohydrate by flounder are discussed in this review.