• Journal of Communications and Networks
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• v.10 no.2
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• pp.148-155
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• 2008

In wireless data communication systems, retransmission of an erroneous packet is inevitable due to the harsh communication environment. In this paper, an efficient retransmission scheme using cooperation from neighboring nodes is investigated. In the cooperative retransmission scheme, an erroneous packet is transmitted to the destination by cooperative nodes which have favorable channels. This cooperative retransmission scheme requires no a priori information of neighboring nodes and has no limitation on the number of cooperating nodes. Distributed beamforming is used to accommodate multiple cooperating nodes. Phase and frequency offsets of cooperating signals are extracted from the NACK message and used to co-phase retransmitted data packets. The outage probability of the cooperative retransmission scheme is analyzed for the case of perfect synchronization and when the offsets are estimated. To reduce the impact of the residual phase and frequency offsets in cooperating signals, a low-rate feedback scheme is also investigated. It is shown that improved outage probability and reduced packet error rate (PER) performance can be achieved even for long data packets. The proposed cooperative retransmission scheme is found to outperform simple retransmission by the source as well as decode-and-forward cooperation.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.3
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• pp.441-457
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• 2011

In this study, the axiomatic design(AD) method is applied to construct the hierarchical structure of evaluation criteria and the AHP method is used to calculate the weights of criteria in order to develop the proposal evaluation index for the overseas weapon system purchasing projects. The common evaluation items as main categories are selected through the review of evaluation criteria from the previous works and projects, relevant regulations and defense policy, and the design matrix using fuzzy concept is established and evaluated by the expert group in each design phase to determine the independency, that is the satisfaction of decoupled or uncoupled design, for each criteria in the same hierarchy when they are derived from the main categories. The establishment of decoupled or uncoupled design matrix provides mutually exclusiveness of how small number of DPs can be accounted for FRs within the same hierarchy. The proposal evaluation index developed in this study will be used as a general proposal evaluation index for the overseas weapon system purchasing projects which there are no systematically established evaluation tools.

• Herbal Formula Science
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• v.16 no.1
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• pp.185-205
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• 2008

The purpose of this study is to determine whether the clinical activity of patients with atopic dermatitis(AD) correlate with their serum cytokine levels. 86 patients with AD were treated with KHS, YMH and GHT. On each visit to the clinic, their skin status was evaluated using the SCORAD index and serum IL-4, $IFN-{\gamma}$, IL-12, IL-13, IL-2 and IL-10 were measured by ELISA. After oral administration of herbal medicine, patients' skin status and subjective parameters such as pruritus and sleeplessness were significantly improved according to regression analysis. In particular, patients aged 0-9 showed stronger responses to treatment, which implies that the younger patients aged, the easier the treatment by herbal formula became. In analysis of the type of chosen herbal medicines, YMH treated group showed a stronger response in reduction of affected lesion, intensity of a lesion and subjective symptoms, while KHS treated group showed the least reduction. The levels of serum IL-4, $IFN-{\gamma}$ and IL-2 correlated with disease activity. Moreover, in patients under 0-9, the IL-4 level had a corrleation with disease activity; patients under 10-19 showed a correlation between the levels of IL-4 and IL-2 and disease activity; patients under 20-29 showed a correlation between the levels of IL-2, IL-12 and $IFN-{\gamma}$ and disease activity. In comparison with chosen herbal medicines, the groups treated with YMH or GHT treated group showed a correlation between the levels of IL-4, IL-12 and IL-2 and disease activity while KHS treated group did not. Our data suggest that serum levels of IL-4 and IL-13 are good indicators of clinical improvement in treating AD.

• Animal Bioscience
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• v.35 no.5
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• pp.690-697
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• 2022

Objective: This study aimed to evaluate the effect of the ad libitum and restricted feeding regimen on fasting heat production (FHP) and body composition. Methods: Twelve Hubbard broilers breeders were selected with the same body weight and submitted in two feeding regimes: Restricted (T1) with feed intake of 150 g/bird/d and ad libitum (T2). The birds were randomly distributed on the treatments in two runs with three replications per treatment (per run). The birds were adapted to the feed regimens for ten days. After that, they were allocated in the open-circuit chambers and kept for three days for adaptation. On the last day, oxygen consumption (VO₂) and carbon dioxide production (VCO₂) were measured by 30 h under fasting. The respiratory quotient (RQ) was calculated as the VCO₂/VO₂ ratio, and the heat production (HP) was obtained using the Brower equation (1985). The FHP was estimated throughout the plateau of HP 12 hours after the feed deprivation. The body composition was analyzed by dual-energy X-ray absorptiometry scanning at the end of each period. Data were analyzed for one-way analysis of variance using the Minitab software. Results: The daily feed intake was 30 g higher to T2 (p<0.01) than the T1. Also, the birds of the T2 had significatively (p<0.05) more oxygen consumption (+3.1 L/kg^0.75/d) and CO₂ production (+2.2 L/kg^0.75/d). That resulted in a higher FHP 359±14 kJ/kg^0.75/d for T2 than T1 296±17.23 kJ/kg^0.75/d. In contrast, the RQ was not different between treatments, with an average of 0.77 for the fasting condition. In addition, protein and fat composition were not affected by the treatment, while a tendency (p<0.1) was shown to higher bone mineral content on the T1. Conclusion: The birds under ad libitum feeding had a higher maintenance energy requirement but their body composition was not affected compared to restricted feeding.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.9
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• pp.15-32
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• 1998

This experiment was carried out to evaluated biological availability of calcium inthe sea mustard, sea tangle and sea lettuce in the rats. Standard diets were made to supply 0.3% of Ca from CaCO3. Consequently, levels each test ingredients to be added were sets by their Cacontents. The ingredients such as sea mustard, sea tangle and sea lettuce wereadded to basal diet at levels of 15.23%, 12.66% and 23.42% respectively. Ingredients of the basal diet were soybean protein, corn oil, alpha-cellulose, methionine, choline cholride and vitamin and mineral premix. Dextrose was added at level up to 100%. Amount of soybean protein was adjustable to make all the diets isontrogenous. Rats were fed ad libitum the diets for 13 days. The results were summarized as follow: 1. Serum calcium levels of the sea mustard group(15.23%) were higher than those of the other group, but rats fed sea lettuce diets appeared to have the lowest value. 2. Ca concentration in tibia were lower in rats fed with sea lettuce, rather than in those with standard diet. 3. Ca concentration in femur of the rats fed seaweeds did not show any significant difference among groups. 4. In the liver weight in groups fed on the all experimental groups were decreased more than that in the case of the standard diet groups.

• Journal of Pharmaceutical Investigation
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• v.34 no.1
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• pp.29-34
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• 2004

The solubility and stability of quercetin in various vehicles were determined. The solubility of quercetin at $28^{\circ}C$ increased in the rank order of isopropyl myristate < oleyl alcohol < propylene glycol monolaurate < oleoyl macrogol­6 glycerides < linoleoyl macrogol-6 glycerides < propylene glycol laurate (PGL) < propylene glycol monocaprylate (PGMC) < polyethylene glycol-8 glyceryl linoleate < caprylocaproyl macrogol-6 glycerides < diethylene glycol mono ethyl ether (DGME). The addition of DGME to non-aqueous vehicles such as PGL ad PGMC markedly increased the solubility of quercetin. From the stability studies, it was found that quercetin was unstable due to rapid oxidation by dissoved oxygen. The addition of a combination of ascorbic acid and edetic acid (EDTA) at 0.1 % markedly decreased the degradation rates of quercetin in 40% polyethylene glycol 400 in saline. Quercetin was relatively unstable in non-aqueous vehicles such as PGL and PGMC alone, and PGL-PGMC co-solvent The degradation of quercetin in such non-aqueous vehicles was fast, depending on temperature. The addition of butylated, hydroxytoluene, butylated hydroxyanisole, citric acid and/or EDTA at 0.1 % was effective in retarding the degradation of quercetin.

• The Korean Journal of Food And Nutrition
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• v.27 no.4
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• pp.673-677
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• 2014

HX106N은 용안육, 맥문동, 단삼 및 천마 등의 4가지 식물로 구성된 추출물로서, 선행 연구에서 amyloid ${\beta}$ peptide에 의한 생쥐의 기억력 저하 및 산화 손상을 억제하는 것으로 밝혀졌다. 이 연구에서는 HX106N이 비선택적 무스카린 수용체 길항제로 잘 알려진 스코폴라민(scopolamine)으로 유도한 콜린성 건망증(cholinergic amnesia)에 어떤 영향을 미치는지를 평가하였다. ICR 생쥐에게 스코폴라민(1 mg/kg body weight, i.p.)을 주입하기 1시간 전에 HX106N(100 mg/kg body weight, p.o.)을 투여하였다. 30분 후 수행한 Y-미로 시험(Y-maze test) 및 수동 회피 시험(passive avoidance test)에서 HX106N는 스코폴라민에 의해 감소되는 자발적 변경 행동(spontaneous alternation) 및 지체시간(step-through latency)을 유의미하게 억제하여 건망증을 개선시키는 것으로 나타났다. 또한 HX106N을 투약 1시간 후 생쥐의 해마와 대뇌피질 부위의 아세틸콜린에스테라제(acetylcholinesterase; AChE)의 활성을 측정한 결과 통계적으로 유의미한 정도의 활성 감소가 관찰되었다. 이러한 결과들을 종합할 때 HX106N은 AD에서 관찰되는 콜린성신경전달 장애로 인한 기억력 저하 억제에 사용될 수 있는 가능성을 가진 것으로 판단된다.

• Journal of Nutrition and Health
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• v.40 no.3
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• pp.235-241
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• 2007

The aim of this study was to define an arginine effect when added to a diet. The influence of arginine supplements on bone mineral density and content were studied in young female Sprague-Dawley rats fed either an arginine supplemented diet or control diet. Twenty four rats (body weight $83{\pm}5g$) were randomly assigned to one of two groups, consuming casein or casein with supplemented arginine diet. All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone mineral density (BMD) and bone mineral content (BMC) were measured using PIXImus (GE Lunar Co, Wisconsin, USA) in spine and femur 3, 6, and 9 weeks after feeding. The serum and urine concentrations of Ca and P were determined. Diet did not affect weight gain and mean food intake. The serum concentration of Ca and P were not changed by arginine supplementation. Urinary Ca excretion was significantly decreased by arginine supplementation. Spine BMD was significantly increased by arginine supplementation on 3 and 6 weeks after feeding. Femur BMD was significantly increased in the group of arginine supplementation on 3, 6, and 9 weeks. Rats fed the arginine-supplemented diet had better bone mineral content than did control diet rats in the experimental period. Therefore, arginine supplementation may be beneficial on spine and femur BMD increment in growing female rats. These are thought to be associated with an arginine-induced growth hormone release. The exact mechanism of this effect remains to be elucidated.

• Journal of Intelligence and Information Systems
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• v.24 no.2
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• pp.37-57
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• 2018

With the spread of smart phones, interest in mobile media is on the increase as useful media recently. Mobile media is assessed as having differentiated advantages from existing media in that not only can they provide consumers with desired information anytime and anywhere but also real-time interaction is possible in them. So far, studies on mobile advertising were mostly researches analyzing satisfaction with, and acceptance of, mobile advertising based on survey, researches focusing on the factors affecting acceptance of mobile advertising messages and researches verifying the effect of mobile advertising on brand recall, advertising attitude and brand attitude through experiments. Most of the domestic mobile advertising studies related to advertisement effect and advertisement attitude have been conducted through experiments and surveys. The advertising effectiveness measure of the mobile ad used the attitude of the advertisement, purchase intention, etc. To date, there have been few studies on the effects of mobile advertising on actual advertising data to prove the characteristics of the advertising platform and to prove the relationship between the factors influencing the advertising effect and the factors. In order to explore advertising effect of mobile advertising platform currently commercialized, this study defined advertising characteristics and media characteristics from the perspective of advertiser, advertising platform and publisher and analyzed the influence of each characteristic on advertising effect. As the advertisement characteristics, we classified advertisement format classified by bar type and floating type, and advertisement material classified by image and text. We defined advertisement characteristics of advertisement platform as Hedonic and Utilitarian media characteristics. As a dependent variable, we use CTR, which is the ratio of response (click) to ad exposure. The theoretical background and the analysis of the mobile advertising business, the hypothesis that the advertisement effect is different according to the advertisement specification, the advertisement material, In the ad standard, bar ads are classified as static framing, Floating ads can be categorized as dynamic framing, and the hypothetical definition of floating advertisements, which are high-profile dynamic framing ads, is highly responsive. In advertising, images with high salience are defined to have higher ad response than text. In the media characteristics classified as practical / hedonic type, it is defined that the hedonic type media has a more relaxed tendency than the practical media, and there is a high possibility of receiving various information because there is no clear target. In addition, image material and hedonic media are defined to be highly effective in the interaction between advertisement specification and advertisement material, advertisement specifications and media characteristics, and advertisement material and media characteristics. As the result of regression analysis on each characteristic, material standard, which is a characteristic of mobile advertisement, and media characteristics separated into 'Hedonic' and 'Utilitarian' had significant influence on advertisement effect and mutual interaction effect was also confirmed. In the mobile advertising standard, the advertising effect of the floating advertisement is higher than that of the bar advertisement, Floating ads were more effective than text ads for image ads. In addition, it was confirmed that the advertising effect is higher in the practical media than the hedonic media. The research was carried out with the big data collected from the mobile advertising platform, and it was possible to grasp the advertising effect of the measure index standard which is used in the practical work which could not be grasped in the previous research. In other words, the study was conducted using the CTR, which is a measure of the effectiveness of the advertisement used in the online advertisement and the mobile advertisement, which are not dependent on the attitude of the ad, the attitude of the brand, and the purchase intention. This study suggests that CTR is used as a dependent variable of advertising effect based on actual data of mobile ad platform accumulated over a long period of time. The results of this study is expected to contribute to establishment of optimum advertisement strategy such as creation of advertising materials and planning of media which suit advertised products at the time of mobile advertisement.

• Journal of Digital Contents Society
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• v.19 no.8
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• pp.1603-1615
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• 2018

In order to achieve the low complexity and area, power in the design of Optical Image Stabilization (OIS) suitable for the smart phone, this paper presents the following design explorations, such as; optimization of gyroscope sampling rate, simple and accurate gyroscope filters, and reduced operating frequency of motion compensation, optimized bit width in ADC and DAC, evaluation of noise effects due to PWM driving. In experiments of gyroscope sampling frequencies, it is found that error values are unvaried in the frequency above 5KHz. The gyroscope filter is efficiently designed by combining the Fuzzy algorithm, to illustrate the reasonable compensation for the angle and phase errors. Further, in the PWM design, the power consumption of 2MHz driving is shown to decrease up to 50% with respect to the linear driving, and the imaging noises are reduced in the driving frequency above 2MHz driving frequency. The operating frequency could be reduced to 5KHz in controller and 10KHz in driver, respectively, in the motion compensation. For ADC and DAC, the optimized exploration experiments verify the minimum bit width of 11bits in ADC as well as 10bits in DAC without the performance degradation.