• 제목/요약/키워드: Suboptimal

검색결과 449건 처리시간 0.025초

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

  • 손숙미;양정숙
    • 대한지역사회영양학회지
    • /
    • 제3권2호
    • /
    • pp.167-173
    • /
    • 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.

  • PDF

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

  • 김경근;진승희;윤태성;박진배
    • 대한전기학회논문지:전력기술부문A
    • /
    • 제48권6호
    • /
    • pp.735-746
    • /
    • 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.

  • PDF

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

  • 윤석호;김선용
    • 대한전자공학회논문지TC
    • /
    • 제41권5호
    • /
    • pp.19-25
    • /
    • 2004
  • 이 논문에서는, 칩비동기 직접수열 대역확산 시스템을 위한 최적 및 준최적 직렬 코드 포착 기법을 제안한다. 기존의 직렬코드 포착 기법은 상관기 출력값 각각을 하나씩 차례대로 정해진 문턱값과 비교하는 방식이며, 이러한 방식은 칩동기 가정아래에서는 최적임이 알려져 있다. 하지만 역확산 이전에 이루어지는 코드 포착 과정에서는 각 칩의 신호대잡음비가 매우 낮기때문에 칩동기 가정이 만족되기 어렵다. 따라서 이 논문에서는 좀더 현실적이고 일반적인 칩비동기 환경을 생각하고 이를 위해 최대우도 기준에 바탕을 둔 최적 직렬 코드 포착 기법을 제안한다. 또한, 좀더 간단하면서도 최적 기법과 비슷한 성능을 지니는 준최적 기법을 국소 최적 검파 전력 기준에 바탕을 두고 제안한다. 마지막으로 수치 해석 결과를 통해, 제안한 최적 및 준최적 직렬 코드 포착 기법이 칩비동기 환경아래에서 기존의 직렬 코드 포착 기법보다 뛰어남을 보인다.

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
    • /
    • 제24권3호
    • /
    • pp.407-413
    • /
    • 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.

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

  • 고석준
    • 대한전자공학회논문지TC
    • /
    • 제44권1호
    • /
    • pp.98-105
    • /
    • 2007
  • 본 논문에서는 Maximum Likelihood(ML) 알고리즘을 변형한 Suboptimal ML 타이밍 검출기를 제안한다. 본 논문에서 제안하는 Suboptimal ML방식은 참조신호 생성과정이 Early-Late gate 또는 ML 방식에 비해 간단하면서도 타이밍 검출기의 이득은 거의 동일한 값을 얻을 수 있다. 또한, 타이밍 추적기는 데이터 판별을 이용하기 때문에 적은 타이밍 오차 범위만이 추적 가능하다. 즉, 펄스폭이 0.7ns인 4차 가우시안 모노사이클을 사용하였을 경우, 추적 가능한 타이밍 오차는 ${\pm}0.06ns$이다. 따라서 탐색기는 높은 정확도를 갖는 획득성능을 갖고 있어야 한다. 성능 분석은 잡음뿐만아니라 송신기와 수신기의 펄스 생성과정에서 사용되는 오실레이터 지터를 고려한다. 컴퓨터 모의 실험 결과는 타이밍 검출기의 평균과 분산 및 타이밍 추적기의 추적 성능을 보여준다. 그리고 이동성에 의해 타이밍 오차가 점차적으로 증가하는 경우를 가정하여 추적성능을 제시한다. 본 논문은 타이밍 추적기의 성능을 제시하기 위해 하나의 복조기인 단인 상관기만을 고려한다.

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

  • 송경영;김재홍;노종선;정하봉
    • 한국통신학회논문지
    • /
    • 제35권1C호
    • /
    • pp.1-7
    • /
    • 2010
  • 본 논문은 하나의 소스, 하나의 릴레이, 그리고 하나의 목적 노드가 각각 두 개의 송수신 안테나를 갖는 협력 통신망에서, 연판정 후 전달(soft-decision-and-forward: SDF) 방식의 성능을 쌍 오류 확률(pairwise error probability: PEP)을 이용해 분석한다. 준정지 레일리 페이딩 채널에서 최적 그리고 차선의 전력 분배비를 결정한다. 최적의 전력 분배는 평균 PEP를 최소로 하는 것이나 일반적으로 구하기 어려우므로, 다이렉트와 릴레이 링크의 잡음 대 신호비의 곱(product signal-to-noise ratio: product SNR)을 최대화하는 전력 분배 전략을 고려한다. 모의실험 결과를 통해 높은 SNR 구간에서는 차선의 전력 분배 방식의 성능이 최적의 성능에 근접함을 보인다.

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

  • 김경덕;남명모;김강웅;이해영;허샛별;강용진;손맹현
    • 한국수산과학회지
    • /
    • 제42권3호
    • /
    • pp.262-267
    • /
    • 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
    • /
    • 제13권4호
    • /
    • pp.294-299
    • /
    • 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.