• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.2
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• pp.151-159
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• 2004

A detailed evaluation of relative toxicity of fluoride to die 5th instar larvae of PM and NB$_4$D$_2$ races of silkworm and the effects of lethal, sublethal and prevailing levels of fluoride in groundwater on the growth, economic characters and fecundity of the silkworm, Bombyx mori (Lepidoptera: Bombycidae) were studied. The feeding of mulberry, Morus alba leaves treated with lethal and sublethal doses of fluoride to PM and NB$_4$D$_2$ races of silkworms from the beginning of the 5th instar to the end of the feeding period resulted in significant reduction in growth, single cocoon weight, single shell weight, silk index, average filament length, and fecundity when compared to controls. These manges were more pronounced on exposure to lethal dose than sublethal dose and in general, the changes induced by fluoride were more striking in NB$_4$D$_2$ than PM, indicating the greater resistance of PM to higher fluoride levels. Groundwater quality in sericulturally important villages of Karnataka and Andhra Pradesh States has been studied with special reference to the presence of fluoride. On exposure to dose of prevailing levels in the waters of sericulturally important areas, die changes observed on growth, economic characters and fecundity were slightly lower when compared to controls and the decrease was found to be insignificant (P$\geq$0.05). It was concluded that, though minute dose (4.0 ppm) of fluoride did not have any toxic impact, it is toxic at higher concentrations to silkworms.

• Korean Journal of Poultry Science
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• v.28 no.1
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• pp.41-47
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• 2001

Two experiments were conducted to investigate the effents of feeding single or combined probiltics on performance and intestinal micreflora of broiler chicks for five weeks. Diets based on corn and soybean meal contained 21.50, 19% CP and 3,100, 3,150kcal/kg ME for starting and finishing period, respectively. Lactobacillus salvarius isolated from chicks intestine(LSC), Lactobacillus salvarius isolated from piglet(LSP), Bacillus polyfermenticus(BP) were fed with alone and mixed ones at the level of 0.21 and 0.1% in experiment 1 and 2, respectively. Three hundred eighty four chicks were randomly assigned to eight treatments with four replicates of 12 chicks each per treatment. Weight gain, feed consumption, feed conversion ratio(FCR) were weekly measured for 5 weeks. The number of intestinal micreflora was examined at the end of experiment. In both experiments, weight gain of chicks fed probiltics tended to be similar or higher than control, but was not in LSC+LSP treatment. Feed intake was not consistent among treatments. In experiment 1, FCR of chicks fed LSC alone was the lowest of all treatments, whereas it was significantly higher in LSC+LSP treatments than control(P〈0.05). In experiment 2, LSP supplemental groups tended to increase FCR compared to the control. The number of ileal E. coli was the lowest in LSP alone treatment of experiment 1, whereas cecal E. coli was higher concentration in probiotics supplemental groups than control. Total Lactobacillus of chicks fed probiotics was decreased in ileum, but was no consestency in cecum. In experiment 2, ileal total yeast tended to be higher in probiotics supplemental groups except LSP alone supplement than control. Total Lactobacillus of chicks fed LSC or LSP alone treatments was significantly higher than control(P〈0.05).

• Advances in pediatric surgery
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• v.20 no.2
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• pp.43-47
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• 2014

Purpose: Hypertrophic pyloric stenosis (HPS) is known to be one of the most common cause of surgery for infants and pyloromyotomy was considered to the standard treatment. There has been an ongoing debate about whether laparoscopic pyloromyotomy (LP) or open pyloromyotomy (OP) is the best option for treating HPS. The aim of this study is to evaluate safety and effectiveness of LP by comparing the clinical results of both surgical strategies performed by single surgeon. Methods: Between January 2000 and December 2013, 60 patients who underwent pyloromyotomy at Asan Medical Center performed by a surgeon were followed: open-supraumbilical incision (n=36) and LP (n=24). The parameters included sex, age and body weight at operation. Clinical outcomes included operation time, time to full feeding, postoperative hospital stay, and postoperative complications. Results: There were no significant differences in characteristics, postoperative hospital stay between the two groups. Time to full feeding was shorter in LP (OP 24.5 hours vs. LP 19.8 hours; p=0.063). In contrast, the mean operation time was longer in LP (OP 37.5 minutes vs. LP 43.5 minutes; p=0.072). Complications such as perforation of mucosal layer (OP 1 vs. LP 0) and wound problems (OP 2 vs. LP 0) were found to be not worse in laparoscopic group as compared with open group. Conclusion: There has no difference both laparoscopic and open-supraumbilical incision in terms of postoperative hospital stay, time to full feeds and frequency of complications.

• Korean Journal of Veterinary Research
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• v.39 no.6
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• pp.1126-1140
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• 1999

Renal failure is one of the main causes of economic impacts in the poultry industry and complex syndrome with different severity of clinical signs caused by multiple nephropathogenic factors such as infectious bronchitis viral infection and excess salt and calcium in diet. To evaluate the correlation between severity of renal failure and the causative nephropathogenic factors, one-day-old specific pathogen free chicks were treated with either single causative factor or multiple causative factors described as above. Each group was designed as control for non-treated control, IB for infectious bronchitis virus (IB virus) infection, IBHNa for IB virus infection with high diet salt, IBHCa for IB virus infection with high diet calcium, IBHNC for IB virus infection with high diet salt and calcium, HNa for high diet salt, HCa for high diet calcium and HNC for high diet salt and calcium. Chickens were inoculated with IB virus at 1-day-old and remained on their respective diets until 21 day of age. The high dietary salt feeding groups such as IBHNa, IBHNC, HNa, HNC increased water intake, watery diarrhea, general subcutaneous edema and the high dietary calcium feeding groups such as IBHCa and IBHNC showed severe visceral gout. Two more than treated groups caused high mortality in comparison with the single treated groups. IB virus exposure significantly increased urate deposition and lymphocytic interstitial nephritis. Especially urate deposition dramatically increased when excess diet calcium was combined together. In excess diet salt treated groups enlarged edematous kidneys were observed and hypertrophy of glomeruli were showed. These results suggest that IB virus enhanced the incidence and severity on chicken renal failure clearly related to the quantity of salt and calcium.

• Korean Journal of Poultry Science
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• v.29 no.3
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• pp.225-231
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• 2002

Total 240 of ISA Brown layers were employed in this experiment to study the effects of single or mixed feeding of Lactobacillus and yeast on the performance and intestinal microflora of laying hens. They were randomly allocated to six dietary treatments; None(Control), Pichia farinosa(PF), Lactobacillus crispatus avihen1 (LCH), Lactobacillus vaginalis avihen1(LVH), LCH＋PF, and LVH＋PF. Viable microflora were added to meet 3${\times}$10$\^$6/ cfu PF and 10$\^$7/ cfu Lacrobacillus per g of feed. There were four replicates per treatment, and 10 birds per replicates. Laying performance was recorded for 10 weeks, followed by a metabolism trial during which nutrient utilization, pattern of intestinal microflora and fecal NH$\sub$3/ emission were examined. Egg production and daily egg mass of birds fed either single or mixed microorganisms were significantly higher than those of the control(P<0.05). Egg weight and feed intake were not statistically different among all treatments. However, feed conversion ratio tended to improve by the supplementation of microbes. Digestibility of crude protein, ether extract and crude ash tended to improve in Lactobacillus treatments, however, there were not statistically different. With regards to the number of intestinal microbes, number of anaerobes were increased in microbes feeding group. Eggshell quality of PF layers was significantly poorer than those of the other treatments. No consistent trend was found in Haugh Unit among all treatments. Fecal NH$\sub$3/ gas emission was significantly lower in LVH, LVH＋PF and LCH＋PF than the other treatments(P<0.05). From the result of this experiment, it could be concluded that single or mixed feeding of Lactobacillus and yeast improves the laying performance and decreases the fecal ammonia gas emission. No synergic effect was found when both microbes were mixed and fed to the layers.

• Korean Journal of Poultry Science
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• v.25 no.2
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• pp.79-89
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• 1998

Dietary levels of single cell protein(SCP) 0 %, 5 %, 10 % and 15 % were included in experimental diets. The purpose of this experiment is to examine the effects of diets containing different levels of SCP on the performance of broiler chicks, including the nutrient availabilities, compared to that of the commercial diet. In order to evaluate the nutritive value of SCP, feeding and metabolism trial were conducted with a total of 160 broiler chicks for a period of 4 weeks. Contents of CP and pure protein in the composition of SCP were 67 % and 32. 05 %, respectively. In general, diets with over 10 % SCP substitution had significantly decreased body weight gain compared to the control diet. Feed intake of chicks fed SCP supplemental groups was significantly decreased compared to that of control, especially observed the significant difference in proportion to increas mg the levels of SCP. The feed efficiency was decreased by the addiition of SCP, but was not significantly different between control and SCP supplemental groups. The digestibilities of DM, CP and NFE tended to be similar among treatments, whereas crude fiber treated with SCP tended to be lower digestibility than control. In conclusion, the optimum dietary supplemental SCP would be less 5 % for broiler growth in this experiment.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.4
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• pp.1458-1470
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• 2018

In this letter, a new dual-port Multiple-Input Multiple-Output (MIMO) antenna is introduced which has two independent signal feeding ports in a single antenna element to achieve smaller antenna volumes for the 5G mobile applications. The dual-port structure is implemented by adding a cross coupled semi-loop (CCSL) antenna as the secondary radiator to the ground short of inverted-F antenna (IFA). It is found that the port to port isolation is not deteriorated when an IFA and CCSL is combined to form a dual-port structure. The isolation property of the proposed antenna is compared with a polarization diversity based dual-port antenna proposed in the literature [9]. The operating frequency range is 3.3-4.0 GHz which is suitable for places where $4{\times}4$ MIMO systems are supposed to be deployed such as in China, EU, Korea and Japan at the band ${\times}$ (3.3 - 3.8GHz. The measured 6-dB impedance bandwidths of the proposed antennas are larger than 700 MHz with isolation between the feeding ports higher than 18 dB [1-2]. The simulation and measurement results show that the proposed antenna concept is a very promising alternative for 5G mobile applications.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.10 s.113
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• pp.1007-1019
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• 2006

In this paper, the synthesis method of multibeam radiation pattern with multi-directional beams and nulls is proposed. Genetic algorithm is applied for the optimization of amplitude and phase of the feeding signal into each element that is structured in planar array of single patch antenna with an arbitrary field distribution. To verify the validity of the proposed method, $2{\times}2$ planar array antenna is used for the measurement and the measured far field radiation pattern is compared with the simulation result. As a result, the synthesis of multibeam radiation pattern is implemented by the optimization of amplitude and phase of the feeding signal into each element of $8{\times}8$ planar array antenna system.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.7 s.172
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• pp.146-154
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• 2005

Recently, the high-speed and intelligence technology of machine tools are developed for the high efficiency of productivity Under the operating condition from the high-speed of machine tools, the various failure modes can occur in core units of manufacturing system. Therefore it is for the reliability concept of machine tool to be required in a design level. And the above-stated technology must be accommodated in the feeding and spindle subsystem, etc those are the core units of machine tools. In this study, we are developed the test-bed of sliding cover (C-plate) in order to evaluating reliability and estimating failure modes of feeding subsystem under operating conditions. The reliability experiment using the developed test-bed and the additional structural analysis executed on single and double structure. We found out the weak parts of sliding cover and were able to predict a life cycle from the experiment results. In this study, we propose the new C-plate model with double link structure to apply the high-speed machine tool in the fundamental guideline.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.8
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• pp.878-883
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• 2003

New feeding structures using linearly and exponentially tapered lines to planar microstrip resonators are proposed. These can overcome the design problems from coupling losses and impedance mismatching by increasing the coupling efficiency. The variation of its feeding angle is evaluated for the insertion loss and bandwidth and the feedline length is optimized at ${\lambda}_g$/2. The ring resonators and patches fed by the tapered line have been designed and implemented. The experimental results show that the insertion loss is enhanced by about 7 dB. Both rings and antennas are better matched, without disturbing the single-mode resonance or distorting their radiation pattern