• Title/Summary/Keyword: Suboptimal

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The Difference of Lead and Cadmium Concentration of Blood, Urine and Hair between Children with Suboptimal Iron Status and Normal Children (철분부족아동과 정상아동의 혈액, 소변, 머리카락 속의 납, 카드뮴 수준 차이에 관한 연구)

  • 손숙미;양정숙
    • Korean Journal of Community Nutrition
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    • v.3 no.2
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    • pp.167-173
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    • 1998
  • This study was performed to assess the lead and cadmium status of children residing in urban factory area and to see if there is a difference of lead and cadmium status between the group with normal iron status. The mean lead concentration of male hair was 9.55ppm which is significantly higher than 6.61 ppm that of female. The mean lead concentration of male urine sample was 0.04ppm, 10.3ppm and $48.14\mu{g/L}$, which is higher than 0.08ppm, 6.08ppm and $20.69\mu{g/L}$ of normal group, respectively. In a suboptimal group the proportion of children whose urinary lead is higher than normal$(35\mu{g/L)$was 87.3%, whereas 2.5% for a normal group. The mean cadmium concentration of male hair was 2.58ppm, which is higher than 2.48ppm that of a female. The mean cadmium concentration of erythrocyte, hair and urine was 0.25ppm, 2.65ppm and $38.83\mu{g/L}$, which is higher than 0.20ppm, 2.40ppm and $19.78\mu{g/L}$ of the normal group, respectively. The proportion of children whose urinary cadmium level is higher than the low limit of risk of cadmium intoxication$(40\mu{g/L)}$ was 21.4%, whereas 0% for a mormal group. Urinary lead and cadmium level showed significantly negative correlation with the RBC count, hematocrit, hemoglobin and serum ferritin, whereas they had significantly positive correlation with FEP/Hb(p<0.01). There was no correlation between the IQ and the level of lead and cadmium.

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Design of Decentralized $H^\infty$ Filter using the Generalization of $H^\infty$ Filter in Indefinite Inner Product Spaces (부정 내적 공간에서의$H^\infty$ 필터의 일반화를 통한 분산 $H^\infty$ 필터의 설계)

  • Kim, Gyeong-Geun;Jin, Seung-Hui;Yun, Tae-Seong;Park, Jin-Bae
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.6
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    • pp.735-746
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    • 1999
  • We design the robust and inherently fault tolerant decetralized$$H^infty$$ filter for the multisensor state estimation problem when there are insufficient priori informations on the statistical properties of external disturbances. For developing the proposed algorithm, an alternative form of suboptimal$$H^infty$$ filter equations are formulated by applying an alternative form of Kalman filter equations to the indefinite inner product space state model of suboptimal$$H^infty$$ filtering problems. The decentralized$$H^infty$$ filter that consists of local and central fusion filters can be designed effciently using the proposed alternative$$H^infty$$ filiter gain equations. The proposed decentralized$$H^infty$$ filter is robust against un-known external disturbances since it bounds the maximum energy gain from the external disturbances to the estimation errors under the prescribed level$$r^2$$ in both local and central fusion filters and is also fault tolerant due to its inherent redundancy. In addition, the central fusion equations between the global and local data can reduce the unnecessary calculation burden effectively. Computer simulations are made to ceritfy the robustness and fault tolerance of the proposed algorithm.

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Decision Statistics for Noncoherent Serial PN Code Acquisition In Chip-Asynchronous DS/SS Systems (칩비동기 직접수열 대역확산 시스템에서 비동기 직렬 의사잡음코드 포착을 위한 결정통계량)

  • 윤석호;김선용
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.5
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    • pp.19-25
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    • 2004
  • In this paper, we propose optimal and suboptimal serial code acquisition schemes for chip-asynchronous direct-sequence spread-spectrum systems. The conventional serial code acquisition scheme is to compare each value of correlator outputs with a threshold individually. However, such a scheme is optimum only under the chip-synchronous assumption which is actually very difficult to be held prior to acquisition at the receiver because the signal-to-noise ratios before despreading are very low. In this paper, an optimal serial code acquisition scheme is derived based on the maximum-likelihood criterion under the more realistic and general chip-asynchronous environments. A suboptimal scheme, which is simpler but yields comparable performance to the optimal one, is also derived based on the criterion of local detection power Numerical results show that, under the chip-asynchronous environments, both the optimal and suboptimal serial code acquisition schemes outperform the conventional serial code acquisition scheme.

Effect of Dietary Protein and Lipid Levels on Compensatory Growth of Juvenile Olive Flounder (Paralichthys olivaceus) Reared in Suboptimal Temperature

  • Cho, S.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.3
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    • pp.407-413
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    • 2011
  • Effect of dietary protein and lipid levels on compensatory growth of juvenile olive flounder (Paralichthys olivaceus) was determined in suboptimal temperature ($13.4{\pm}1.42^{\circ}C$). Five hundred forty fish averaging 79.2 g were randomly distributed into 27 of 300 L flow-through tanks (20 fish/tank). Nine treatments were prepared in triplicate: fish were hand-fed with control (C) diet for 10 weeks (10WF-C); four fish groups were starved for 1 week and then fed with C, high protein (HP), high lipid (HL) and combined high protein and high lipid (HPL) diets for 9 weeks, referred to as 9WF-C, 9WF-HP, 9WF-HL, 9WF-HPL, respectively; and other four fish groups were starved for 2 weeks and then fed with C, HP, HL and HPL diets for 8 weeks, referred to as 8WF-C, 8WF-HP, 8WF-HL and 8WF-HPL, respectively. Weight gain and specific growth rate of fish in 9WF-HP, 9WF-HPL, 8WF-HP and 8WF-HPL treatments were higher than those of fish in 9WF-HL and 8WF-HL treatments. Feed efficiency of fish in 8WF-HP treatment was higher than that of fish in 9WF-C, 9WF-HL and 8WF-HL treatments. Protein efficiency ratio of fish in 10WF-C, 8WF-C, 8WF-HP and 8WF-HPL treatments was higher that that of fish in 9WF-HL and 8WF-HL treatments. Juvenile olive flounder subjected to 2-week feed deprivation could achieve full compensatory growth with dietary supplementation of protein or combined high protein and high lipid.

Data Decision Aided Timing Tracker in IR-UWB System using PPM (PPM 변조방식의 IR-UWB 시스템에서 데이터 결정방식을 이용한 타이밍 추적기)

  • Ko, Seok-Jun
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.44 no.1
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    • pp.98-105
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    • 2007
  • In this paper, we propose a timing detector using suboptimal maximum likelihood method. The proposed method has an simple reference signal generator. Additionally, timing detector's gain of the proposed method is the same to Early-Late gate and ML method. We reveal that tracking range of time tracker is narrow because of using data-decision, that is, tracking range is ${\pm}0.06ns$ for the 4-order Gaussian monocycle with 0.7ns pulse width. Therefore we can find that searcher must have very accurate acquisition procedure. When estimating a performance of time tracker, we consider a jitter in transmitter and receiver's pulse generation process as well as background noise. By using computer simulation, we propose mean/variance of timing detector and tracking process. Also we consider a mobility in tracking process, i.e., timing error modeled ramp function. In order to propose a performance of time tracker, we consider only one correlation demodulator.

Power Allocation Strategy for Soft-Decision-and-Forward Cooperative Communication System (연판정 후 전달 방식에 대한 전력 분배 전략)

  • Song, Kyoung-Young;Kim, Jae-Hong;No, Jong-Seon;Chung, Ha-Bong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.1C
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    • pp.1-7
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    • 2010
  • In this paper, the performance of the soft-decision-and-forward (SDF) protocol in the cooperative communication network with one source, one relay, and one destination, where each node has two transmit and receive antennas, is analyzed in terms of the bit error rate (BER) obtained from the pairwise error probability (PEP). For the slow-varying Rayleigh fading channel, the optimal and suboptimal power allocation ratios are determined without feedback. The optimal power allocation can be obtained by minimizing the average PEP. For the tractability, an alternative strategy of maximizing the product SNR of direct and relay links, which we call the suboptimal power allocation, is considered. Through the numerical analysis, we show that the performance gap between the suboptimal and the optimal power allocation is negligible in the high SNR region.

Effects of Feeding Rate and Feeding Frequency on Growth and Body Composition of Sub-adult Flounder Paralichthys olivaceus in Suboptimal Water Temperature (사료 공급율 및 공급횟수가 저수온기에 사육된 넙치 미성어의 성장 및 체조성에 미치는 영향)

  • Kim, Kyoung-Duck;Nam, Myung-Mo;Kim, Kang-Woong;Lee, Hae-Young;Hur, Saet-Byeol;Kang, Yong-Jin;Son, Maeng-Hyun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.42 no.3
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    • pp.262-267
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    • 2009
  • Two 15-week feeding trials were conducted to investigate feeding rate and feeding frequency for growth of sub-adult flounder in suboptimal water temperature ($12^{\circ}C$). In the first experiment, duplicated groups of fish (initial mean weight of 279 g) were fed a extruded pellet once a day at the different feeding rates of 0.1, 0.15, 0.2, 0.3% body weight per day (BW/d), and satiation (0.32% BW/d). Weight gain and feed efficiency were increased significantly (P<0.05) with increase in feeding rates from 0.1 to 0.3% BW/d, but there were no significant differences in weight gain and feed efficiency of fish fed the diet between 0.3% BW/d and to satiation. Crude protein content of dorsal muscle of fish fed the 0.1% BW/d diet was significantly (P<0.05) lower than that of the other groups. In the second experiment, duplicated groups of fish (initial mean weight of 281 g) were fed to apparent satiation with a extruded pellet at three different feeding frequencies (one meal every two days, one meal a day and two meals a day). Weight gain, feed efficiency and condition factor of fish fed one meal every two days were significantly (P<0.05) lower than those of fish fed one meal and two meals a day, but there were no significant differences in weight gain, feed efficiency and condition factor of fish fed between one meal and two meals a day. Based on the results of this study, optimum feeding frequency is one meal a day with satiation feeding for growth and feed efficiency of sub-adult flounder (270-350 g) in suboptimal water temperature ($12^{\circ}C$).

Effects of Dietary Nutrient Composition on Compensatory Growth of Grower Olive Flounder Paralichthys olivaceus under Different Feeding Regimes at Suboptimal Temperature

  • Kim, Kyoung-Tae;Choi, In-Cheol;Cho, Young-Jin;Lee, Jong-Ha;Kang, Yong-Jin;Cho, Sung-Hwoan
    • Fisheries and Aquatic Sciences
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    • v.13 no.4
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    • pp.294-299
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    • 2010
  • The effects of dietary nutrient composition on compensatory growth of grower olive flounder (Paralichthys olivaceus) under different feeding regimes at suboptimal temperature were determined. Four hundred five fish weighing 271.2 g were distributed into 27 300 L flow-through tanks (15 fish per tank). Nine treatments were prepared in triplicate: fish were hand-fed with control (C) diet for 12 weeks (12WF-C); four groups of fish were starved for 1 week and then fed C, high-protein (HP), high-lipid (HL), or combined high-protein and high-lipid (HPL) diets for 11 weeks; these groups are referred to as 11WF-C, 11WF-HP, 11WF-HL, and 11WF-HPL, respectively. Four other groups of fish were starved for 2 weeks and then fed C, HP, HL, and HPL diets for 10 weeks; these groups are referred to as 10WF-C, 10WF-HP, 10WF-HL, and 10WF-HPL, respectively. Weight gain and specific growth rate of fish from 12WF-C group were greater than those of fish from 11WF-C, 11WF-HP, 11WF-HL, 10WF-C, 10WFHP, and 10WF-HL groups, but not different from those of fish from 11WF-HPL and 10WF-HPL groups. Feed-efficiency ratio of fish from 12WF-C, 11WF-HP, 11WF-HPL, 10WF-HL, and 10WF-HPL groups was higher than that of fish in 11WF-C, 11WF-HL, 10WF-C, and 10WF-HP groups. The results of this study demonstrated that grower olive flounder subjected to 1- or 2-week feed deprivation were able to achieve full compensatory growth at suboptimal temperature only when fed HPL diet.