• 제목/요약/키워드: 1546

검색결과 148건 처리시간 0.028초

Synthesis and characterization of silanized-SiO2/povidone nanocomposite as a gate insulator: The influence of Si semiconductor film type on the interface traps by deconvolution of Si2s

  • Hashemi, Adeleh;Bahari, Ali
    • Current Applied Physics
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    • 제18권12호
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    • pp.1546-1552
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    • 2018
  • The polymer nanocomposite as a gate dielectric film was prepared via sol-gel method. The formation of crosslinked structure among nanofillers and polymer matrix was proved by Fourier transform infrared spectroscopy (FT-IR). Differential thermal analysis (DTA) results showed significant increase in the thermal stability of the nanocomposite with respect to that of pure polymer. The nanocomposite films deposited on the p- and n-type Si substrates formed very smooth surface with rms roughness of 0.045 and 0.058 nm respectively. Deconvoluted $Si_{2s}$ spectra revealed the domination of the Si-OH hydrogen bonds and Si-O-Si covalence bonds in the structure of the nanocomposite film deposited on the p- and n-type Si semiconductor layers respectively. The fabricated n-channel field-effect-transistor (FET) showed the low threshold voltage and leakage currents because of the stronger connection between the nanocomposite and n-type Si substrate. Whereas, dominated hydroxyl groups in the nanocomposite dielectric film deposited on the p-type Si substrate increased trap states in the interface, led to the drop of FET operation.

Effects of dietary extrusion on rumen fermentation, nutrient digestibility, performance and milk composition of dairy cattle: a meta-analysis

  • Sazli Tutur Risyahadi;Rima Shidqiyya Hidayati Martin;Novia Qomariyah;Suryahadi Suryahadi;Heri Ahmad Sukria;Anuraga Jayanegara
    • Animal Bioscience
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    • 제36권10호
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    • pp.1546-1557
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    • 2023
  • Objective: The present study aimed to evaluate the effects of extruded and unextruded feeding on the performance, milk composition, digestibility and ruminal fermentation of dairy cows through a meta-analysis. Methods: The database was compiled from 53 studies in Scopus and PubMed. The data were analyzed using a random effects model in OpenMEE software. Extruded feed was grouped as the experiment group while and the others as control group. The bias of publication in the main parameter of dairy performance was evaluated by a funnel plot. Results: The result showed that extruded feed enhanced the milk yield, dry matter and crude protein digestibility, butyrate and valerate acid production (p<0.05). Meanwhile, the extruded feed significantly decreased the milk fat and protein concentration (p<0.05). Also, the iso-butyrate and iso-valerate in unextruded feeding was significantly higher than the extruded feed (p<0.05). Conclusion: It was concluded from the meta-analysis that extruded feed effectively improved the milk production and milk lactose concentration, dry matter and protein digestibility, but not the milk fat and protein concentration.

한일간 대기굴절 채널환경을 고려한 전파모델 연구 (Study of the Propagation Model considering Refractive Channel Environment between Korea and Japan)

  • 이경량;김성권
    • 한국전자통신학회논문지
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    • 제8권1호
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    • pp.49-54
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    • 2013
  • 본 논문에서는 대략 250 km 이상 떨어져 있는 한국과 일본의 대기 채널 환경에 대한 분석을 하였으며, 대기 굴절도 변화량에 따르는 한일간의 채널 환경에 Radio Duct 현상이 발생하고 있으며, 그로 인한 전파 월경으로 채널 간섭이 발생하고 있음을 확인하였다. 일본 NHK에서 측정한 한국채널 수신전계강도 실험결과를 바탕으로 인접국간 전파예측모델 P 1546의 유효한 굴절도 변화량 보정치로 1% 시간율에서 -91.80 [N-units/km], 10% 시간율에서 -43.92 [N-units/km], 50% 시간율에서 -586.19 [N-units/km]의 보정된 굴절도 변화량을 제시하였으며, 제시된 굴절도 변화량은 한일간의 대기 채널 환경을 반영하는 실질적인 전파모델 예측수행에 기여할 것으로 기대된다.

Contribution of thermal-hydraulic validation tests to the standard design approval of SMART

  • Park, Hyun-Sik;Kwon, Tae-Soon;Moon, Sang-Ki;Cho, Seok;Euh, Dong-Jin;Yi, Sung-Jae
    • Nuclear Engineering and Technology
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    • 제49권7호
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    • pp.1537-1546
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    • 2017
  • Many thermal-hydraulic tests have been conducted at the Korea Atomic Energy Research Institute for verification of the SMART (System-integrated Modular Advanced ReacTor) design, the standard design approval of which was issued by the Korean regulatory body. In this paper, the contributions of these tests to the standard design approval of SMART are discussed. First, an integral effect test facility named VISTA-ITL (Experimental Verification by Integral Simulation of Transients and Accidents-Integral Test Loop) has been utilized to assess the TASS/SMR-S (Transient and Set-point Simulation/Small and Medium) safety analysis code and confirm its conservatism, to support standard design approval, and to construct a database for the SMART design optimization. In addition, many separate effect tests have been performed. The reactor internal flow test has been conducted using the SCOP (SMART COre flow distribution and Pressure drop test) facility to evaluate the reactor internal flow and pressure distributions. An ECC (Emergency Core Coolant) performance test has been carried out using the SWAT (SMART ECC Water Asymmetric Two-phase choking test) facility to evaluate the safety injection performance and to validate the thermal-hydraulic model used in the safety analysis code. The Freon CHF (Critical Heat Flux) test has been performed using the FTHEL (Freon Thermal Hydraulic Experimental Loop) facility to construct a database from the $5{\times}5$ rod bundle Freon CHF tests and to evaluate the DNBR (Departure from Nucleate Boiling Ratio) model in the safety analysis and core design codes. These test results were used for standard design approval of SMART to verify its design bases, design tools, and analysis methodology.

구조화된 환자교육이 뇌졸중 환자의 조기재활에 관한 지식과 활동수행에 미치는 영향 (The Effect of the Structured Education on the Early Rehabilitation Knowledge and Activity Performance of the C.V.A. Patients)

  • 이혜진;이향련
    • 대한간호학회지
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    • 제27권1호
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    • pp.109-119
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    • 1997
  • This study has been attempted to set up the strategies of the nursing which can promote the activity performance for early rehabilitation for the patients by examining the effect of the structured patient education on the early rehabilitation knowledge and activity performance of the C.V.A patients. The study method has been done by investigating the experiment group and control group in advance through the question papers and interview and observation on 65 patients who had been hospitalized at oriental medicine hospital of K Medical Center from July 1st 1995 to the end of Sep, 1995. The analysis of the collected material had been done for the homogeneity test in which general characters of experiment group and control group had been tested by X²and the homogeneity test of ADL by t-test. To test the hypothesis the t-test had been given for the difference of the early rehabilitation knowledge and activity performance between the two groups and the correlation between early rehabilitation knowledge and activity performance had been tested by Pearson's Correlation Coefficient. The result of the test of the hypothesis is as the below. 1 The 1st hypothesis “The experiment group which had received the structured education should be higher in the early rehabilitation knowledge than the control group” was supported(t=4.45. p=.000). 2. The 2nd hypothesis “The experiment group which received the structured education should be higher in the early rehabilitation activity performance than the control group”was supported(t=2.11, p=.036). 3. The 3rd hypothesis “The higher the early rehabilitation knowledge of the patient the higher the activity performance degree” was rejected (r=.1546, p=.219). In conclusion, the patients who received the structured education showed the increase in the degree of early rehabilitation knowledge and activity performance, so it has been judged that education has been prerequisite in increasing the knowledge and activity performance of early rehabilitation.

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레이저 도플러 원리를 이용한 유체 가속도 측정 (Effect of fringe divergence in fluid acceleration measurement using LDA)

  • 전세종;홀거노박;캠트로피아;성형진
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.1546-1551
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    • 2004
  • The laser Doppler technique is well-established as a velocity measurement technique of high precision for flow velocity. Recently, the laser Doppler technique has also been used to measure acceleration of fluid particles. Acceleration is interesting from a fluid mechanics point of view, since the Navier Stokes equations, specifically the left-hand-side, are formulated in terms of fluid acceleration. Further, there are several avenues to estimating the dissipation rate using the acceleration. However such measurements place additional demands on the design of the optical system; in particular fringe non-uniformity must be held below about 0.0001 to avoid systematic errors. Relations expressing fringe divergence as a function of the optical parameters of the system have been given in the literature; however, direct use of these formulae to minimize fringe divergence lead either to very large measurement volumes or to extremely high intersection angles. This dilemma can be resolved by using an off-axis receiving arrangement, in which the measurement volume is truncated by a pinhole in front of the detection plane. In the present study an optical design study is performed for optimizing laser Doppler systems for fluid acceleration measurements. This is followed by laboratory validation using a round free jet and a stagnation flow, two flows in which either fluid acceleration has been previously measured or in which the acceleration is known analytically. A 90 degree off-axis receiving angle is used with a pinhole or a slit.

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강우시간분포모형의 선정에 따른 홍수유출수문곡선 특성 (Charactristics of Flood Hydrographs by Time Distribution of Rainfall)

  • 노황원;최현일;지홍기
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2009년도 학술발표회 초록집
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    • pp.1546-1550
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    • 2009
  • 최근 증가하고 있는 집중호우로 인해 피해 규모가 대형화 되어가고 있는 추세로 수공구조물 설계시 보다 정확한 수문분석을 요구 하고 있다. 강우의 시간분포는 정확한 수공구조물의 설계시 첨두홍수량 산정에 가장 중요한 영향을 미친다. 따라서 본 연구에서는 지역의 기상학적, 지형학적 특성에 맞는 적절한 강우분포형을 제시하고자 한다. 본 연구는 금호강권역의 단시간 강우에 대한 시간분포형을 결정하기 위하여 기존 강우의 시간분포방법 중에서 개념상 비교적 단순하면서도 물리적으로 의미를 갖는 Mononobe분포, Yen & Chow분포, Keifer & Chu분포의 방법을 이용하였다. 대상지점은 금호강권역의 가창으로 재현기간 50년의 6시간, 24시간 강우의 시간적 분포특성을 비교분석한 결과 6시간 확률강우량에서는 Mononobe 분포와 Keifer & Chu 분포의 첨두치가 비교적 크게 나타났고 24시간 확률강우량에서는 Keifer & Chu 분포의 첨두치가 가장 크게 나타났다. Yen & Chow 분포의 경우 6시간 강우의 첨두치에 비해 24시간 강우의 첨두치가 급격히 감소하는 것을 알 수 있다. 또한 확률강우를 이용해서 홍수유출량을 분석한 결과 6시간, 24시간의 첨두홍수량은 Keifer & Chu 분포가 가장 크게 나오는 것으로 나타났고 첨두시간 역시 Keifer & Chu 분포가 가장 빠른 것으로 나타났다. 최근 다양한 설계강우의 시간분포 방법들이 실제 강우분포의 특성을 표현하고 있지만 이러한 방법들 중에서 실제로 유역에 가장 적합한 시간분포 방법을 결정하기란 어렵다. 하지만, 첨두홍수량 결정을 위해서는 여러 가지 방법들 중 그 지역을 가장 대표할 수 있는 강우분포 방법을 선택해야만 한다. 따라서 분석지점 이외의 다양한 실제 지점에 대해 설계홍수량을 산정해 봄으로써 다른 설계강우의 시간분포 방법을 이용하여 산정한 결과의 비교 검토가 필요할 것으로 사료된다.

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Joint Subcarriers and Power Allocation with Imperfect Spectrum Sensing for Cognitive D2D Wireless Multicast

  • Chen, Yueyun;Xu, Xiangyun;Lei, Qun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권7호
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    • pp.1533-1546
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    • 2013
  • Wireless multicast is considered as an effective transmission mode for the future mobile social contact services supported by Long Time Evolution (LTE). Though wireless multicast has an excellent resource efficiency, its performance suffers deterioration from the channel condition and wireless resource availability. Cognitive Radio (CR) and Device to Device (D2D) are two solutions to provide potential resource. However, resource allocation for cognitive wireless multicast based on D2D is still a great challenge for LTE social networks. In this paper, a joint sub-carriers and power allocation model based on D2D for general cognitive radio multicast (CR-D2D-MC) is proposed for Orthogonal Frequency-Division Multiplexing (OFDM) LTE systems. By opportunistically accessing the licensed spectrum, the maximized capacity for multiple cognitive multicast groups is achieved with the condition of the general scenario of imperfect spectrum sensing, the constrains of interference to primary users (PUs) and an upper-bound power of secondary users (SUs) acting as multicast source nodes. Furthermore, the fairness for multicast groups or unicast terminals is guaranteed by setting a lower-bound number of the subcarriers allocated to cognitive multicast groups. Lagrange duality algorithm is adopted to obtain the optimal solution to the proposed CR-D2D-MC model. The simulation results show that the proposed algorithm improves the performance of cognitive multicast groups and achieves a good balance between capacity and fairness.

Effect of Nursing Frequency and Creep Feed Provision on the Milk and Feed Intake and Performance of Zero Day Weaned Piglets Reared on a Dummy Sow

  • Weng, R.C.;Edwards, S.A.;Hsia, L.C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제22권11호
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    • pp.1540-1546
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    • 2009
  • One hundred and forty-four piglets with an average birth weight of 1,672${\pm}$13.4 g were used to evaluate different feeding strategies for piglets reared from birth on a dummy sow. A 3${\times}$2 factorial experiment compared three nursing frequencies (1, 3 or 6 h intervals) and two feeding regimes (milk only, or milk combined with access to creep feed and water). The piglets which were nursed at one hour intervals had the lightest body weights at all days, and the poorest combined milk and creep feed dry matter conversion efficiency to piglet body weight gain in the second week. Piglets which were nursed at 3 h intervals had the heaviest body weight at day 15 and 22, but those nursed at 6 h intervals achieved similar body weight by days 29 (milk withdrawal) and 36. Piglets offered creep feed were observed to wean themselves before cessation of milk availability, and the timing of this self-weaning depended on the nursing frequency. The piglets nursed at one hour intervals weaned themselves between day 22 and day 29, those nursed at 3 h intervals weaned themselves between day 15 and day 22, whilst those nursed at 6 h intervals weaned themselves between day 8 and day 15. The piglets which were nursed at 6 h intervals had the highest total dry matter intake in weeks 3 and 4 when fed with milk, creep feed and water but not when fed milk only. They consequently had the poorest dry matter conversion efficiency in the fourth week and overall when fed with milk, creep feed and water, but not when fed milk only. It is concluded that the optimal management routine under these conditions is a 3 h nursing cycle with provision of supplementary creep feed and water.

동의보감 해수문 16종 해수의 원문과 인용문헌에 관한 비교고찰 (Consideration of Comparing the Original Texts with Quotations in 16 Kinds of Cough Part in Haesu Chapter of Donguibogam.)

  • 이정욱;이시형
    • 대한한의정보학회지
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    • 제15권2호
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    • pp.7-56
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    • 2009
  • Objective: The purpose of this study is to compare the original texts with quotations in 16 Kinds of Cough Part in Haesu Chapter of Dong-Yi-Bo-Gam and to find out the ideas of Huh Jun(許浚, 1546-1615; the author of Dong-Yi-Bo-Gam) in there. Methods: I compared the original texts with quotations in 16 Kinds of Cough Part in Haesu Chapter of Dong-Yi-Bo-Gam. Results: 1. There is only one quoted sentence which perfectly matches with original text in 16 Kinds of Cough Part in Haesu Chapter of Dong-Yi-Bo-Gam. The other sentences are all modified while they are quoted by Huh Jun, at least one word. 2. The arrangement order of 'medical effect', 'consisting medicines and their dosages' and 'doctrine in application' were rearranged following the form of Dong-Yi-Bo-Gam when being quoted. 3. In cases of reciting the text, Huh Jun tries to clarify the original source of the context. However, instead of using original quotations he recited rephrased quotes from other sources. 4. Huh Jun cites from not only cough parts of other texts but also asthma(喘症) or heat(積熱) parts. 5. Titles of original text books are recorded in the end of all sentences of Dong-Yi-Bo-Gam, but there are a few wrong titles recorded. Conclusion: In consideration of the above-mentioned, the Dong-Yi-Bo-Gam is not the mere collection of various Oriental Medical books, but the Classic of Oriental Medicine to hold Huh Jun's own opinion.

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