• 방사선산업학회지
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• 제8권1호
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• pp.1-5
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• 2014

This study investigated the reduction of microbial population and sensory properties in red pepper powders irradiated by gamma ray, electron beam, and X-ray. Populations of total aerobic bacteria and yeast & molds in red pepper powders were decreased by irradiation treatment in a dose-dependent manner. Gamma ray, electron beam, and X-ray at doses above 8 kGy caused 100% inhibition on growth of aerobic bacteria in red pepper powders. Inhibitory activity of X-ray on sterilization of red pepper powders was significantly equal to or higher compared to gamma ray and electron beam. Color and off flavor in red pepper powders were no significant difference among the control and samples irradiated with gamma ray, electron beam, and X-ray. As a result, the gamma ray, electron beam, and X-ray irradiation can be used to sterilize the microbial growth in red pepper powders without quality loss.

• Earthquakes and Structures
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• 제10권3호
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• pp.589-611
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• 2016

This paper presents an analytical study aimed at evaluating the seismic performance of steel moment resisting frames (MRFs) retrofitted with different approaches. For this, 3, 6 and 12 storey MRFs having four equal bays of 5 m were selected as the case study models. The models were designed with lateral stiffness insufficient to satisfy code drift and hinge limitations in zones with high seismic hazard. Three different retrofit strategies including traditional diagonal bracing system and energy dissipation devices such as buckling restrained braces and viscoelastic dampers were used for seismic upgrading of the existing structures. In the nonlinear time history analysis, a set of ground motions representative of the design earthquake with 10% exceedance probability in fifty years was taken into consideration. Considering the local and global deformations, the results in terms of inter-storey drift index, global damage index, plastic hinge formations, base shear demand and roof drift time history were compared. It was observed that both buckling-restrained braces and viscoelastic dampers allowed for an efficient reduction in the demands of the upgraded frames as compared to traditional braces.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권11호
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• pp.5323-5343
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• 2018

Mobile applications and social networks tend to enhance the need for high-quality content access. To address the rapid growing demand for data services in mobile networks, it is necessary to develop efficient content caching and distribution techniques, aiming at significantly reduction of redundant content transmission and thus improve content delivery efficiency. In this article, we develop optimal cooperative content cache and distribution policy, where a geographical cluster model is designed for content retrieval across the collaborative small cell base stations (SBSs) and replacement of cache framework. Furthermore, we divide the SBS storage space into two equal parts: the first is local, the other is global content cache. We propose an algorithm to minimize the content caching delay, transmission cost and backhaul bottleneck at the edge of networks. Simulation results indicates that the proposed neighbor SBSs cooperative caching scheme brings a substantial improvement regarding content availability and cache storage capacity at the edge of networks in comparison with the current conventional cache placement approaches.

• International Journal of Computer Science & Network Security
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• 제21권5호
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• pp.133-138
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• 2021

The concept of inclusive development provides equal opportunities for all participants in access to the labor market and resource allocation. This concept emphasizes the equality of human capital, the ecological state of the environment, social protection and food security. This concept is fundamentally different from the standard perception of economic growth, because it has broader goals than simply increasing incomes and GDP. It rejects the position that positive results are an automatic consequence of growth; here the basic condition is human development and increase of its well-being, reduction of poverty. Therefore, it is not the result of distribution that becomes primary, but the involvement in the process of social reproduction. An alternative system of characterization of the country's position according to the resulting indicator of the Inclusive Development Index was presented at the World Economic Forum in Davos. In this research the methodical development of the system of estimation of the index of inclusive development for regions of the NUTS 4 level of the European classification is resulted.

• Asian-Australasian Journal of Animal Sciences
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• 제21권8호
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• pp.1196-1200
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• 2008

An experiment was conducted to evaluate the physiological changes of laying hens subjected to feed removal during induced molting while received probiotics in the drinking water. Post-molt performance and egg quality criteria were also studied. Ninety 78-week-old Hy-line W36 laying hens were divided into two treatment groups according to equal body weight and subjected to induced molting by continuous feed removal until around 30% BW reduction. The experiment lasted 12 wks consisting of 4-wk molting and 8-wk post-molt periods. Treatment 1 received no probiotics and was considered as the control. Treatment 2 was similar to the control except that hens received probiotics in the drinking water at 400 mg/L during feed deprivation. The results indicated that hens in both groups went out of production by Day 5. However, hens received probiotics reached 5 and 50% egg production sooner than the control (30 and 52 days vs. 31 and 54 days). Starvation during molting increased heterophil to lymphocyte (H/L) ratio, hematocrit and plasma T4 and $Na^+$ levels while plasma T3 and Cl- levels were decreased. Probiotics had no significant impact on BW reduction during molt. Post-molt egg production and egg mass were higher in hens which previously received probiotics, but these responses were not significant. However, feed conversion ratio was significantly better in hens which received probiotics. Hematocrit, plasma thyroid hormone concentrations (T3 and T4) and plasma $Na^+$, $K^+$ and Cl- levels during molting were not significantly influenced by supplementation of probiotics. However, H/L ratio showed a significant (p<0.05) reduction in birds which received probiotics suggesting beneficial effects of this product for feed-deprived laying hens. No significant difference was observed in post-molt egg quality criteria.

• Wind and Structures
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• 제30권6호
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• pp.663-678
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• 2020

Robust semi-active vibration control of wind turbines using tuned mass dampers (TMDs) is a promising technique. This study investigates a 1.5 megawatt wind turbine controlled by eight different types of tuned mass damper systems of equal mass: a passive TMD, a semi-active varying-spring TMD, a semi-active varying-damper TMD, a semi-active varying-damper-and-spring TMD, as well as these four damper systems paired with an additional smaller passive TMD near the mid-point of the tower. The mechanism and controllers for each of these TMD systems are explained, such as employing magnetorheological dampers for the varying-damper TMD cases. The turbine is modelled as a lumped-mass 3D finite element model. The uncontrolled and controlled turbines are subjected to loading and operational cases including service wind loads on operational turbines, seismic loading with service wind on operational turbines, and high-intensity storm wind loads on parked turbines. The displacement and acceleration responses of the tower at the first and second mode shape maxima were used as the performance indicators. Ultimately, it was found that while all the semi-active TMD systems outperformed the passive systems, it was the semi-active varying-damper-and-spring system that was found to be the most effective overall - capable of controlling vibrations about as effectively with only half the mass as a passive TMD. It was also shown that by reducing the mass of the TMD and adding a second smaller TMD below, the vibrations near the mid-point could be greatly reduced at the cost of slightly increased vibrations at the tower top.

• 대한전자공학회논문지TC
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• 제43권3호
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• pp.32-38
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• 2006

본 논문에서는 실제 다중안테나를 사용하지 않고 부반송파를 가상의 다중안테나 역할을 하게 하여 OFDM 기반의 셀룰러 시스템에서 셀간 간섭을 감쇄하는 기법을 제안한다. 제안된 기법은 주파수 재사용률이 1인 fully-loading된 OFDM 셀룰러 시스템에서 셀 경계에 존재하는 단말기의 셀간 간섭 감쇄에 특히 효과적이다. 본 논문에서는 SISO과 MISO 환경에서 셀간 간섭 감쇄를 위한 기법이 각각 제안되었으며, 제안된 기법은 심볼 타이밍 옵셋에 강건하고, 인접한 셀의 간섭에 따라 자원의 크기를 조절함으로써 효율적으로 셀간 간섭을 감쇄할 수 있다는 장점이 있다. 또한 제안된 가상 MIMO 방식에서 채널의 separability를 향상할 수 있는 virtual signature randomizer (VSR) 개념이 제안되었다. 모의실험을 통하여 제안된 기법이 셀간 간섭 및 섹터간 간섭을 감쇄하는데 효과적임을 기존의 방법과 비교하여 분석한다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권1호
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• pp.19-25
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• 2006

The effect of vitamin E supplementation on plasma ${\alpha}$-tocopherol level, total antioxidant level and reproductive performance in Murrah buffaloes was studied during periparturient period. Twenty-four advance pregnant buffaloes were randomly divided into four equal groups as $T_1$, $T_2$, $T_3$ and $T_4$ and were supplemented with 0, 1,000, 1,500 and 2,000 IU of ${\alpha}$-tocopheryl acetate (Merck) from 60 days prepartum to 30 days postpartum and 0, 500, 750 and 1,000 IU from 30 to 60 days postpartum, respectively. Blood samples were collected at -60, -45, -30, -15, -7, 0, 7, 15, 30 and 60 days of parturition and were analyzed for plasma ${\alpha}$-tocopherol and total antioxidant activity (TAA). The intake of DM, CP and TDN did not vary among different groups. Plasma ${\alpha}$-tocopherol and TAA around parturition (-7 to 15 day) in $T_3$ and $T_4$ were significantly higher than the control group. There was 17% reduction in retention of fetal membranes (RFM) and metritis in $T_4$ than control. The post partum estrus interval averaged 58.00, 55.33, 51.83 and 43.00 days in $T_1$, $T_2$, $T_3$ and $T_4$ respectively. There was significant reduction in days open in both $T_3$ and $T_4$ in comparison to $T_1$ group (127,130 Vs.146). All the vitamin E supplemented groups showed reduction in days open than their previous lactation performance. Supplementation of vitamin E at $1,500IU\;d^{-1}$ from 60 day prepartum to 30 day post partum to buffaloes exhibited beneficial effect on plasma ${\alpha}$-tocopherol level and TAA around parturition and continuation of its supplementation at $1,000IU\;d^{-1}$ from 30 to 60 days of lactation improved post partum reproductive performance of buffaloes.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.803-808
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• 2006

This paper was a study about noise reduction through flow stabilization in duel using experimental method and numerical analysis at the same time. To determine the fan's type three kinds of fans(axial fan, centrifugal fan, and axial fan with centrifugal type) was examined to investigate the suitability for duct. As a result, under the equal number of rotation 2000 RPM, performance of an axial fan with centrifugal type was the most superior by 55dBA at 4.3CMM among other fans. After this, analyzed the results of the numerical analysis to find out the optimum design of pitch angle such as $0^{\circ},\;10^{\circ},\;15^{\circ}\;and\;20^{\circ}$. The intensity of turbulence was low when pitch angle was $15^{\circ}$ and air volume became peak by 5.08 CMM. It was observed that axis component of velocity increased gradually when pitch angle increased from $0^{\circ}\;to\;20^{\circ}$. Finally, designed the shapes of D/S(Down Stream) in duct that agreed inlet angle($\delta$) of stationary blades with pitch angle($\beta$) of axial fan with centrifugal type and derived flow to duct medial, and changed the shape of motor-mount to reduce occurance of unstable vortex in tip of impeller, and embodied noise reduction and improvement of air flow rate through flow stabilization.

• 한국전산구조공학회논문집
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• 제15권4호
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• pp.639-647
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• 2002

본 연구에서는 원주형 절취 독본(dogbonc) 내진 접합부 도입에 따른 철골모멘트골조의 횡강성 감소 정도를 용이하게 산정할 수 있는 실용적 해석기법을 제안하였다. 된 연구의 방안은 원래의 원주형 절취 형상의 독본에서 발생하는 신장량과 동일한 크기의 신장량이 유발되도록 등가의 균등한 유효폭을 갖는 독본 형상으로 치환하는 것에 근거하고 있다. 등가 유효폭을 도입하는 목적은 공액보법을 적용하여 보의 휨변형에 의한 골조의 횡변위 성분을 유도할 때 수행되는 전분을 해석적으로 하기 위함이다. 이러한 접근법의 타당성을 먼저 검증된 유한요소해석모델에 의해 확인한 후, 기둥, 패널존 그리고 보의 변형에서 기인하는 골조의 횡변위 성분을 독본의 존재를 고려하여 해석적으로 유도하였다. 이 유도결과를 이용한 사례분석에 의할 때, 독본의 도입에 따른 횡변위 증가율은 2%∼3%(횡강성 감소율로는 1%∼2%) 정도로서 실무적으로 무시할 수 있는 크기로 나타났다.