• Title/Summary/Keyword: $L_2-gain$

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Performance evaluation for the channel estimation of RLS adaptive algorithm using pilot symbols for IMT-2000 system (IMT-2000 시스템의 파일럿 심볼을 이용한 RLS 적응형 채널추정 알고리즘의 성능 평가)

  • 구제길;최형진
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.37 no.2
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    • pp.54-61
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    • 2000
  • This paper presents the performance evaluation of channel estimation algorithm using RLS algorithm lot W-CDMA reverse link over Rayleigh fading channels. By obtaining BER(Bit Error Rate) performance through computer simulations, the RLS(Recursive Least Square) algorithm is compared with the existing WMSA(Weighted Averaging)(K=1,3) and constant gain algorithm. The channel structure, modulation and pilot patterns are applied to the ARIB (Association of Radio Industries and Business) and 3GPP (3rd Generation Partnership Project) ITU-R proposal for the IMT-2000. The BER performance of RLS algorithm with linear interpolation is similar to that of WMSA(K=1) and slightly superior to that of constant gain algorithm at low Doppler frequencies. Also, RLS algorithm performance is better than that of the WMSA(K=1,3) and constant gain algorithms about 4dB at BER=2.0$\times$$10^{-2}$ and Doppler frequencies $F_D$=320Hz. With increasing Doppler frequency, therefore, the BER performance of RLS algorithm with linear interpolation is superior to WMSA(K=L.3) and constant rain algorithms.

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Effects of Dietary Chelated Fe and Yeast Fe on Growth Performance and Body Composition in Broiler Chicks (유기태 철과 효모철의 첨가급여가 육계의 성장 및 체조성에 미치는 영향)

  • Na S.J.;Oh J.I.;Uuganbayar D.;Jung D.K.;Kim H.Y.;Moon S.T.;Yang C.J.
    • Korean Journal of Poultry Science
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    • v.33 no.2
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    • pp.113-119
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    • 2006
  • This study was carried out to investigate the effects of dietary Saccharomyces cerevisiae (wild yeast mutant) and Saccharomyces cerevisiae hFeHLC (ferritin containing yeast) and chelated Fe on growth performance and body composition of broiler chicks. A total of 252 (1-day old) 'Ross' broiler chicks were allotted to seven dietary treatments: I) control without iron supplementation, 2) 0.1% wild yeast mutant (YM03), 3) 1.0% wild yeast mutant, 4) 0.1% ferritin containing yeast (YF04), 5) 1.0% ferritin containing yeast, 6) 0.01% chelated Fe and 7) 0.1% chelated Fe. The highest weight gain obtained from broilers fed 0.01% chelated Fe was 2,121g, the lowest weight gain obtained from broilers fed control diet was 2.087g. The growth performance results were not significantly different in weight gain, feed intake and feed conversion ratio of broilers diets containing wild yeast, ferritin containing yeast and chelated Fe supplementation and control diets (P>0.05). The lowest iron content in meat was for control 30.51 mg/dL and the highest Fe content was for 0.1% ferritin containing yeast 41.58 mg/dL, but these were not significantly different (P>0.05).

Effect of Dietary L-carnitine Supplementation on Serum and Liver Lipid Composition and Antioxidant Defense System in Rats fed with Different Types of Fat (지방의 종류가 다른 식이에 L-카르니틴을 첨가했을 때 흰쥐의 혈청과 간의 지질성분과 항산화계에 미치는 영향)

  • 원향례
    • The Korean Journal of Community Living Science
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    • v.15 no.1
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    • pp.77-83
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    • 2004
  • The aim of this study was to investigate the effects of L-carnitine on the components of serum and liver and the effects on the anti-oxidant system. For this purpose, five experimental groups were setup. For fat source, perilla oil enough with unsaturated fatty acid and beeftallow enough with saturated fatty acid were supplemented together with L-carnitine to the rats. Five experimental groups kept eight Sprague-Dawley rats respectively, They were co group supplemented with basic diet or AIN-93, PO group supplemented with perilla oil, POC group supplemented with perilla oil and L-carnitine, BT group supplemented with beeftallow, and BTC group supplemented with beeftallow and L- carnitine. The results are. 1) Weight gain, food intake and FER were not different significantly among the experimental groups. 2) Significant difference was observed in serum total lipid(P<0.05), serum triglyceride(P<0.05), serum total cholesterol (P<0.05)and serum LDL cholesterol(P<0.05). Serum total lipid and serum triglyceride were significantly low in the groups supplemented with L-carnitine. Serum total cholesterol showed difference with the supplementation of L-carnitine in BTC only. LDL cholesterol showed no significant difference with the supplementation of L-carnatine, but total values of LDL-cholesterol were high in groups supplemented with beeftallow. 3) Total cholesterol in liver was low in POC group with the supplementation of L-carnitine however, there was no difference in BTC group with the supplementation of L-carnitine. In summary, dietary L-carnitine did not influence the weight gain, food intake and food efficiency ratio among the experimental groups, but had an effect of lowering the serum total lipid and triglyceride significantly in both groups which were supplemented with L-carnitine. The effect of lowering of sew total cholesterol with the supplementation of L-carnitine in beeftallow group(BTC) only. The effect of lowering of liver total cholesterol with the supplementation of L-carnitine in perilla oil group(POC) only.

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A Study on Fabrication and Performance Evaluation of Wideband 2-Mode HPA for the Satellite Mobile Communications System (이동위성 통신용 광대역 2단 전력제어 HPA의 구현 및 성능평가에 관한 연구)

  • 전중성;김동일;배정철
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.3 no.3
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    • pp.517-531
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    • 1999
  • This paper presents the development of the 2-mode variable gain high power amplifier for a transmitter of INMARSAT-M operating at L-band(1626.5-1646.5 MHz). This SSPA(Solid State Power Amplifier) is amplified 42 dBm in high power mode and 36 dBm in low power mode for INMARSAT-M. The allowable error sets +1 dBm of an upper limit and -2 dBm of a lower limit, respectively. To simplify the fabrication process, the whole system is designed by two parts composed of a driving amplifier and a high power amplifier, The HP's MGA-64135 and Motorola's MRF-6401 are used for driving amplifier, and the ERICSSON's PTE-10114 and PTF-10021 are used the high power amplifier. The SSPA was fabricated by the circuits of RF, temperature compensation and 2-mode gain control circuit in aluminum housing. The gain control method was proposed by controlling the voltage for the 2-mode. In addition, It has been experimentally verified that the gain is controlled for single tone signal as well as two tone signals. The realized SSPA has 42 dB and 36 dB for small signal gain within 20 MHz bandwidth, and the VSWR of input and output port is less than 1.5:1 The minimum value of the 1 dB compression point gets 5 dBm for 2-mode variable gain high power amplifier. A typical two tone intermodulation point has 32.5 dBc maximum which is single carrier backed off 3 dB from 1 dB compression point. The maximum output power of 43 dBm was achieved at the 1636.5 MHz. These results reveal a high power of 20 Watt, which was the design target.the design target.

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Microstrip Antenna for ISM Band using L-Shaped feeding structure (L형 급전구조를 이용한 ISM대역용 마이크로스트립 안테나 설계)

  • Park, Chang-Hyun;Kim, Pyoung-Gug;Kim, Kab-Ki
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2007.04a
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    • pp.440-443
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    • 2007
  • In this paper, microstrip antenna is designed for industrial-scientific-medical(ISM)band of S-Band. We proposed that radiation element of antenna, which is rectangle patch shape. The feeding structure used L-shaped structure. Center frequency and -l0dB bandwidth are investigated by change of length and width in patch plane. And maximum gain, front to back ratio and 3dB beam width is presented by simulation radiation pattern of antenna in frequency ISM Band. The center frequency is 2.45GHz, band width is $2.314{\sim}2.577GHz$ with 263MHz(11%). And the antenna maximum gain is 9.3dBi, 3dB beam width E-plane is $52.5^{\circ}$, H-plane is $64.7^{\circ}$.

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Effects of Dietary Mealworm (Tenebrio molitor L.) Powder in Poultry Diets on Poultry Production and Ammonia Emissions in Poultry Litter (가금류 사료에 갈색거저리 분말을 첨가시 가금생산성과 깔짚내 암모니아 발생에 미치는 영향)

  • Yang, Hee-Hyun
    • Journal of Environmental Science International
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    • v.31 no.3
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    • pp.275-279
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    • 2022
  • This study was conducted to examine the performance of poultry production and ammonia emissions from poultry litter when the mealworm (Tenebrio molitor L.) powder was fed to broilers and ducks. In Experiment 1, a total of 180 1-day-old broilers (Arbor acres) were allocated to two treatments with three replicates in a completely randomized design. In Experiment 2, ducks were used in the same method as in Experiment 1. The dietary treatments were as follows: basal diets as control and basal diets with 1.5% Tenebrio molitor L. powder as T1. In Experiment 1, broiler production was not affected by the addition of mealworm powder (p>0.05). Ammonia from broiler litter was observed significantly different in the two treatments at 4 and 5 weeks (p<0.05); however, in other weeks ammonia measured did not show significance different (p>0.05). In Experiment 2, feeding of mealworm powder had no statistical significance on duck productivity (p>0.05). Ammonia emissions from duck litter were not statistically significant in the two treatments at 2 to 5 weeks (p>0.05); however, there was a difference at 6 weeks (p<0.05). Therefore, the addition of mealworm powder to broiler and duck diets did not only improved weight gain and feed efficiency, but also effectively reduced ammonia in poultry litter.

Effects of Dietary Methionine Levels on Choline Requirements of Starter White Pekin Ducks

  • Wen, Z.G.;Tang, J.;Xie, M.;Yang, P.L.;Hou, S.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.12
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    • pp.1742-1747
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    • 2016
  • A $2{\times}5$ factorial experiment, using 2 dietary methionine levels (0.28% and 0.48%) and 5 dietary choline levels (0, 394, 823, 1,239, and 1,743 mg/kg), was conducted to study the effects of dietary methionine status on choline requirements of starter white Pekin ducks from 7 to 28 days of age. Four hundred eighty 7-d-old male White Pekin ducks were randomly allotted to ten dietary treatments, each containing 6 replicate pens with 8 birds per pen. At 28 d of age, weight gain, feed intake, and feed/gain were measured and the legs of all ducks from each pen were examined for incidence of perosis. Perosis and growth depression were observed in choline-deficient ducks and supplementation of choline reduced perosis and significantly increased weight gain and feed intake regardless of dietary methionine levels (p<0.05). In addition, significant positive effects of dietary methionine supplementation on weight gain, feed intake, and feed/gain were observed at any choline level (p<0.05). Supplementation of 1,743 mg/kg choline in diets alleviated the depression of weight gain and feed intake caused by methionine deficiency at 0.28% methionine level. The interaction between choline and methionine influenced weight gain and feed intake of ducks (p<0.05). At 0.28% methionine level, 1,743 mg/kg choline group caused 4.92% and 3.23% amount of improvement in weight gain and feed intake compared with 1,239 mg/kg choline group, respectively. According to the broken-line regression, the choline requirements of starter Pekin ducks for weight gain and feed intake were 1,472 and 1,424 mg/kg at 0.28% methionine level and 946 and 907 mg/kg at 0.48% methionine level, respectively. It suggested the choline recommendations of starter Pekin ducks on a semi-purified diet were 1448 mg/kg at 0.28% methionine level and 927 mg/kg at 0.48% methionine level, respectively. Compared with the adequate methionine level, menthionine deficiency markedly increased the choline requirements of ducks.

Effect of Lysine-Limited Diets Containing Different Levels of L-Carnitine on Body Weight and Lipid Metabolism in Obesity-Induced Adult Rats (L-Carnitine의 수준이 다른 Lysine 제한식이 섭취가 비만유도 성숙쥐의 체중과 지질대사에 미치는 영향)

  • Kim, Ja-Kyung;Kim, Mi-Kyung
    • Journal of Nutrition and Health
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    • v.40 no.2
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    • pp.118-129
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    • 2007
  • This study was performed to investigate the effect of lysine-limited diets containing different levels of L-carnitine on body weight and lipid metabolism in obesity-induced adult rats. Eight-month-old male Sprague-Dawley rats (n = 90) were raised for one month with high fat diet (40% fat as calorie) to induce obesity. After induction of obesity, rats weighing 739.5 g were randomly blocked into three groups according to the body weight and raised for eight weeks with control diet (Co), 50% lysine-limited diet (-L), 50% lysine limitation with 0.3% pivalate diet (-L + P). Each of three groups was allotted to 0.0% L-carnitine (0.0% CT), 0.5% L-carnitine (0.5% CT) and 2.5% L-carnitine (2.5% CT) groups, respectively. The levels of AST, ALT, total protein and albumin in plasma were within the normal range. Daily food intake and calorie intake tended to be lower in 2.5% CT groups than those of other groups regardless lysine limitation or pivalate intake. And body weight gain and calorie efficiency ratio (weight gain (g) /calorie intake (100 kcal)) were significantly the lowest in 2.5% CT groups among all experimental groups regardless of lysine limitation or pivalate intake. The weights of perirenal, epididymal fat pads and brown adipose tissue in 2.5% CT groups were significantly lower than 0.0% CT groups. Plasma total lipid, triglyceride, total cholesterol concentrations in all groups were not significant by experimental compound. HDL-cholesterol concentrations in -L + P +2.5% CT group were highest in -L + P groups. Levels of hepatic total lipid, triglyceride and total cholesterol in 2.5% CT groups were tend to be lower those than in 0.0% CT groups regardless of dietary lysine limitation and pivalate intake. Fecal total lipid excretions of 2.5% CT groups were significantly lower than in 0.0% CT groups in all experimental groups. But fecal triglyceride excretions of 2.5% CT groups were significantly higher than 0.0% CT groups regardless of lysine limitation and pivalate. In conclusion, there was no difference on body weight and lipid metabolism by dietary lysine limitation and pivalate intake. And feeding of 2.5% L-carnitine was more effective than feeding of 0.5% L-carnitine and 0.0% L-carnitine in reduction of body weight, body fat and lipid metabolism.

Effect of Output-conductance on Current-gain Cut-off frequency in In0.8Ga0.2As High-Electron-mobility Transistors (In0.8Ga0.2As HEMT 소자에서 Output-conductance가 차단 주파수에 미치는 영향에 대한 연구)

  • Rho, Tae-Beom;Kim, Dae-Hyun
    • Journal of Sensor Science and Technology
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    • v.29 no.5
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    • pp.324-327
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    • 2020
  • The impact of output conductance (go) on the short-circuit current-gain cut-off frequency (fT) in In0.8Ga0.2As high-electron-mobility transistors (HEMTs) on an InP substrate was investigated. An attempted was made to extract the values of fT in a simplified small-signal model (SSM) of the HEMTs, derive an analytical formula for fT in terms of the extrinsic model parameters of the simplified SSM, which are related to the intrinsic model parameters of a general SSM, and verify its validity for devices with Lg from 260 to 25 nm. In long-channel devices, the effect of the intrinsic output conductance (goi) on fT was negligible. This was because, from the simplified SSM perspective, three model parameters, such as gm_ext, Cgs_ext and Cgd_ext, were weakly dependent on goi. However, in short-channel devices, goi was found to play a significant role in degrading fT as Lg was scaled down. The increase in goi in short-channel devices caused a considerable reduction in gm_ext and an overall increase in the total extrinsic gate capacitance, yielding a decrease in fT with goi. Finally, the results were used to infer how fT is influenced by goi in HEMTs, emphasizing that improving electrostatic integrity is also critical importance to benefit fully from scaling down Lg.

COPRA MEAL AS A SUPPLEMENT TO CATTLE OFFERED A LOW QUALITY NATIVE PASTURE HAY

  • Hennessy, D.W.;Kempton, T.J.;Williamson, P.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.2 no.2
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    • pp.77-84
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    • 1989
  • Twenty-four Hereford steers, 22 months old and a mean liveweight (${\pm}\;s.e.$) of $250\;{\pm}\;7\;kg$ were used in an experiment to evaluate over 42 days two rates of copra meal supplementation to cattle on a low N ($8.6\;{\pm}\;0.9$ g N/kg dry matter (DM)), low digestible ($45\;{\pm}\;5.2%$ DM) native pasture hay. Steers given the two rates (500, 1000 g/steer/day; i.e. 500C, 1000C) were compared to steers on a non-supplemental diet and to the effects on steers of supplemental urea (30g/steer/day; 30U) or with copra meal (500 g/steer/day; 500C.U), or of cottonseed meal (500 g/steer/day; 500S). Liveweight change was increased (P<0.01) by all of the supplements except by supplemental urea. The most effective treatment, 1000C, increased significantly (P<0.01) liveweight change (946 g/day) in steers above all supplements except those steers given 500C.U (718 g/day). Hay intake per unit liveweight was increased (P<0.05) by 7% by the 30U and 500C.U treatment, and by 9% by 500C; this group having the highest supplements, being greatest (P<0.05) for the 1000C group (6.0 g feed intake/g gain) and least for the 500S supplemented group (11.5 g/g gain). Efficiency was lowest (18.6 g/g gain) for the non-supplemented steers on the basal hay diet. Copra meal N was less degradable (i.e. 29%) in nylon bags over 15 hours in the rumen than was cottonseed meal N (37%), and rumen ammonia concentrations were lower (P<0.05) in cattle supplemented with copra meal (25, 27 mg N/L) than in cattle given urea (36 mg N/L) or cottonseed meal (39 mg N/L). It is concluded that copra meal at a daily rate of 500 g/head, and with rumen soluble nitrogen from urea, is an effective supplement for improving growth of cattle on a low quality forage.