• 제목/요약/키워드: $E_b/N_t$

검색결과 468건 처리시간 0.035초

평판형 액체식 집열기 의 각종 변수 가 집열기 의 열성능 에 미치는 영향 (A Study of Parametric Effects on the Thermal Performance of Flat-Plate Liquid-Heating Solar Collectors)

  • 전문헌;윤석범;추교명
    • 대한기계학회논문집
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    • 제8권2호
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    • pp.145-153
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    • 1984
  • 본 연구에서는 먼저 집열기의 열성능에 관한 가장 전형적인 Hottel-Whillier- Bliss의 모델을 사용하여 모의 실험을 수행하였다. 모의 실험에 사용한 집열기의 주 요 변수는 덮개 유리의 수(N), 집열판의 방사율(.epsilon.$_{p}$), 집열판의 흡수율(.alpha.$_{p}$T),집열기 단위 면적당의 유량(G), 집열기 단열재의 $L_{b}$/ $K_{b}$, 집열기 경사각 (S),일사량(I) 등이며 이들 집열기 변수의 대표치(typical values)를 중심으로 각 변 수의 값을 변화시켜서 여기에 따른 집열기 효율 곡선의 변화를 조사하였다. 모의 실 험결과와 비교하고, 모의 실험에 사용한 수학적 모델이 집열기의 열성능을 평가하는 데에 적합한가를 확인하고, 운전중에 인위적으로 그 값을 조절할 수 있는 운전 변수중 특히 유량(G)의 변화에 따른 집열기 효율변화와 최적유량의 범위를 동시에 실험적으로 조사하기 위하여, 액체 가열식 집열기 시험장치의 회로를 보완하여 실제 태양 아래에 서 실험을 수행하였다.

Radiation effect on the polymer-based capacitive relative humidity sensors

  • Shchemerov, I.V.;Legotin, S.A.;Lagov, P.B.;Pavlov, Y.S.;Tapero, K.I.;Petrov, A.S.;Sidelev, A.V.;Stolbunov, V.S.;Kulevoy, T.V.;Letovaltseva, M.E.;Murashev, V.N.;Konovalov, M.P.;Kirilov, V.N.
    • Nuclear Engineering and Technology
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    • 제54권8호
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    • pp.2871-2876
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    • 2022
  • The sensitivity of polymer-based capacitive relative humidity (RH) sensors after irradiation with neutrons, electrons and protons was measured. Degradation consists of the decreasing of the upper RH limit that can be measured. At the same time, low RH-level sensitivity is almost stable. After 30 krad of absorption dose, RH cut off is equal to 85% of max value, after 60 krad-40%. Degradation reduces after annealing which indicates high radiation sensitivity of the internal circuit in comparison to RH-sensing polymer film.

서울.경기지역 성인여성의 골밀도와 혈압, 칼슘섭취의 상관성 연구 -2011년 국민건강영양조사를 중심으로- (Association of Bone Mineral Density and Blood Pressure, Calcium Intake among Adult Women in Seoul.Kyunggi Area - Based on 2011 KNHANES -)

  • 구재옥
    • 대한지역사회영양학회지
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    • 제18권3호
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    • pp.269-282
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    • 2013
  • This study was carried out to investigate bone mineral density (BMD), blood pressure, calcium, sodium intake and related biochemical variables, and to analyze the relationship between BMD, and blood pressure, physical characteristics, nutrient intakes of Korean adult women. The study subjects were 30~80years old, 513 women living in Seoul and Kyunggi area who participated in 2011 KNHANES. The study subjects were divided into three BMD groups; normal, n = 259 (50.4%), osteopenia, n = 169 (32.9%), and osteoporosis, n = 85 (16.7%). Average height and weight and fat free mass decreased with a decrease in BMD. Average BMD of normal, osteopenia, osteoporosis were 0.87, 0.79, $0.70g/cm^2$, and T-score were 0.42, -0.66, -1.62, respectively. Higher systolic blood pressure, alkaline phosphatase, and triglyceride were significantly associated with a decrease in the BMD. The rates of hypertension were significantly increased from normal to osteoporosis. i.e. 18.5% in normal, 34.3% in osteopenia and 63.5% in osteoporosis. Average nutrientintakes such as protein, fat, calcium, phosphorus, iron, sodium, potassium, vitamin A, vitamin B, vitamin B2, and vitamin C were significantly lower in subjects with lower BMD.n. Average calcium intake of normal, osteopernia and osteoporosis were 528.50, 416.96, 389.56 mg, respectively. There were significant negative correlations between calcium, phosphorus and age, systolic blood pressure, triglyceride. Also, there were negative correlation systolic blood pressure (incomplete sentence). In this study, we found low BMD according to low calcium intake increase the risk of osteoporosis and hypertension rather than sodium intake, also calcium intake decreased with increase age. Therefore, in order to prevent osteoporosis and hypertension, subjects need to be educated regarding the importance of calcium nutrients in diet.

돈 분뇨 액비에 미생물 첨가가 배추의 발아지수에 미치는 영향 (Effect of Microbial Inoculant to Pig Liquid Fertilizer on Germination Index of Chinese Cabbage)

  • 김태일;유용희;정의수;;양창범;김민균
    • 한국축산시설환경학회지
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    • 제11권2호
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    • pp.135-146
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    • 2005
  • 본 연구는 돈 분뇨 액비에 미생물 첨가가 배추의 발아지수에 미치는 효과를 구명하기 위해서 수행하였다. 돈 분뇨 액비는 107일 동안 폭기와 무폭기 상태로 액상비료를 제조하여 공시하였고 미생물 첨가는 $0.05\%,\;0.1\%,\;0.2\%,\;0.3\%$ 수준으로 하였다. $0.05\%$ 미생물 접종 처리구에서 식물 독성이 낮고 발아지수가 높게 나타났다. 첨가수준별 돈분 액비 이용시험에서 초기 돈 슬러리의 액비성상은 T-N 2,873 ppm, T-P 753 ppm, $NH_4-N$ 1,441.6 ppm, $NO_3-N$ 16.48ppm으로 50일이 되면서 폭기조건에서 T-N 3,672 ppm, T-P 164 ppm, $NH_4-N$ 183.87 ppm, $NO_3-N$ 21.97 ppm로 변화하였으며, 무폭기 조건에서 T-N 1,261 ppm, T-P 68 ppm, $NH_4-N$ 161 ppm, $NO_3-N$ 16.87 ppm로 나타났다. 미생물을 처리하지 않고 107일동안 폭기조건과 무폭기 조건으로 액비화한 시료의 발아지수는 각각 83과 40.4이였다. 돈 분뇨 액비를 무산소 제조시 $40\%$ 이상, 호기제조시 $50\%$ 이상의 발아지수가 개선되었다. 이와 같은 결과는 액비제조 처리가 무산소 제조보다는 호기제조 처리가 작물에 양호한 것으로 판단되어지며 이는 호기처리시 총질소의 함량을 높게 유지할 수 있도록 하는 결과인 것으로 사료된다.

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임펄스 잡음과 나카가미 페이딩이 존재할 때 다이버시티 기법과 오류정정 부호를 이용한 무선통신 DS/CDMA 시스템의 오율 특성 (Performance of Radio Communication DS/CDMA System with Diversity Technique and BCH Coding under Impulsive Noise and Nakagami Fading)

  • 김지웅;강희조;이권현
    • 한국전자파학회논문지
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    • 제10권4호
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    • pp.539-549
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    • 1999
  • 본 논문에서는 다중접속간섭. 임펼스 잡음과 나카가미 페이딩 환경에서 DS/CDMA DQPSK 통선시스댐의 B BER 성능을 분석하였다. 고려되는 DS/CDMA DQPSK 통신시스템은 제안한 시스템의 성능을 향상시키기 위하여 최대비 합성(MRC) 다이버시티 수신기법과 오류 정정 BCH 부호화 기법을 채용하였다. 유도한 오율 식을 이용하여 DS/CDMA DQPSK 통신시스댐의 성능을 구하여, 임펄스 지수( A), 가우시안 잡음 전력 대 임펄스 잡음 전력비($\Gamma'$), 다중접속간섭(K), 나카가미 페이딩 파라미터(m), MRC 다이버시티 가지수 (L), 부호의 오류 정정 능력(f), 직접확산 처리 이득(N)과 선호 전력 대 잡음 전력비( $E_b/N_O$)을 함수 로 하여 오율 그래프로 나타내고 분석하였다. 분석한 결과, 제안하는 시스댐의 성능은 무선통신시스댐환경에 서 다중접속간섭, 임펼스 잡음과 나카가미 페이멍에 의해 영향을 받을 수 있다. 또한 희망하는 선호의 전력이 나 임펄스 지수, 가우시안 잡음 천력 대 임펼스 잡음 전력비를 증가시켜 DS/CDMA DQPSK 통신시스댐의 BER 성능을 개선할 수 있음을 알 수 있었다. 그리고 다중접속간섭, 임펄스 잡음과 나카가미 페이딩의 영 향을 억압하기 위해서는 MRC 다이버시티 수산된 DS/CDMA DQPSK 통신시스댐보다는 BCH05.7) 부호화 기법을 적용한 DS/CDMA DQPSK 시스댐이 효율적임을 알 수 있었다.

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Zn1-xFexO의 뫼스바우어 분광학적 연구 (The Study on Mössbauer Spectroscopy of Zn1-xFexO)

  • 김성진;이상률;박철수;김응찬;조영걸;김동호
    • 한국자기학회지
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    • 제18권2호
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    • pp.75-78
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    • 2008
  • $AB_2X_4$((A, B)=Transition Metal, X=O, S, Se) 물질에서의 8면체 자리의 이온 거동과 4면체 자리 이온과의 상호작용에 대하여 많은 연구가 이루어지고 있다. 본 연구에서는 4면체 자리에 비자성 이온인 Zn 이온을 치환함에 따른 자기구조의 변화를 관측하여 8면체 자리의 자기구조를 분석하고자 하였다. Cr이온의 일부를 Fe로 치환한 $[Co_{0.9}Zn_{0.1}]_A[Cr_{1.98}{^{57}Fe_{0.02}}]_BO_4$의 닐온도($T_N$는 90K로 $CoCr_{1.98}{^{57}Fe_{0.02}}O_4$ 비하여 감소하였다. 4.2 K에서의 초미세자기장값의 분석결과, 초미세자기장값의 작은 차이를 보이는 잘 분리된 2-set 형태로 나타났으며, $CoCr_{1.98}{^{57}Fe_{0.02}}O_4$의 초미세자기장값은 488, 478 kOe 인데 반하여, $Co_{0.9}Zn_{0.1}Cr_{1.98}{^{57}Fe_{0.02}}O_4$의 초미세자기장값은 $B_1=486$, $B_2=468$ kOe으로 나타났다. Zn 이온의 치환에 따라서 초미세자기장값의 변화를 알 수 있었다. 이러한 결과로 인하여, Zn 이온이 x=0.1 치환된 물질의 경우, 스핀재정렬온도($T_S$)가 18K으로 감소함을 알 수 있다.

유료양로시설 이용의 의사결정 단계별 결정요인 (The Factors Influencing the Utilization of Charged Retirement Home Services by Stage of Decision-Making)

  • 이성학
    • 보건행정학회지
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    • 제9권1호
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    • pp.110-138
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    • 1999
  • This study intended to understand the factors influencing the utilization of charged retirement home services for the elderly by stage of discision making. At the same time the purpose of the study is also to present the results of this study as data for the expectation of the demand. The subject of this study was non-utilizer (635 persons) and utilizer (62 persons) of charged retirement home services over the age of sixty. Non-utilizer was selected by random sampling in urban and rural area, and utilizer was investigated by census survey in the three charged retirement home. The research method was interview survey by questionaire. The questionaire was composed of 59 items, 25 variables, 5 components. The research model was to add Andersen's Prediction Model. The components were predisposing component, enabling component, need component, actualizing component, psychologic component. The results of this study were as follows. 1)In the stage of recognizing the residence problem, the recognizer were 76.7% (487 persons) of all the non-utilizer. The factors of influencing were property (B=-4.1E-05), solidarity with children (B=-.1070), house satisfaction (B=-.2517), need of charged retirement home (B=.2614). 2)In the stage of selecting an altenative as utilizing of charged retirement home services, the selecter were 41.1% (261 persons) of all the non-utilizer. The factors of influencing were perception of charged retirement home (B=.2790), need of charged retirement home (B=.2971). 3)In the stage of decion-making, the decider were 29.6% (188 persons) of all the non-utilizer. The factor of influencing was need of charged retirement home (B=.3570). 4)In the stage of the actualization, the factors of influencing were charge ability of utilization (B=.1025), significant others (B=.1868). The upper results were implemented by using the statistical methods of frequency, t-test, $$\chi$^{2}$-test, multiple logistic regression ( and P 〈 .05 ).

HDDM, a formula consisting of seven herbs, had anti-diabetic but no immunomodulatory activities in multiple low doses of streptozotocin-treated female of B6C3F1 mice

  • Zheng, Jian Feng;Guo, Tai L
    • Advances in Traditional Medicine
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    • 제9권1호
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    • pp.20-38
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    • 2009
  • The objectives of this study were to determine the effect of herb formula HDDM, a modification of Huangdan decoction that has been shown to be effective in the treatment of glomerulonephritis and chronic renal failure, on the blood glucose levels in multiple low doses (MLD; 50 mg/kg for five consecutive days) of streptozotocin (STZ)-treated female B6C3F1 mice. Initial studies were performed to compare diabetes induction in five strains (e.g., B6C3F1, NOD, CD-1, C3H/HeN and C57BL/6) of mice by MLD-STZ, and immune changes following the treatment. The results suggested that the order of susceptibility to diabetes induction was NOD $\approx$ CD-1 > B6C3F1 $\approx$ C3H > C57BL/6. Furthermore, STZ modulation of T cell development, differentiation and activation might play a role in diabetes induction by MLD-STZ treatment. MLD-STZ-induced diabetes in female B6C3F1 mice was moderate, which allowed the evaluation of drug-induced protection or exacerbation of diabetes to be performed. As such, modulation of blood glucose by HDDM, which consisted of Da Huang (Radix Et Rhizoma Rhei), Huang Qi (Radix Astragali Seu Hedysari), Dan Shen (Radix Salviae Miltiorrhizae), Yin Yang Huo (Herba Epimedii), Yi Yi Ren (Semen Coicis or Coix lacryma-jobi), Mai Dong (Radix Ophiopogonis) and Shan Zhu Yu (Fructus Corni), was evaluated in MLD-STZ-treated female B6C3F1 mice. The results suggested that HDDM could lower the blood glucose levels, but it had no immunomodulatory activities. Additionally, HDDM-treated mice exhibited improved glucose tolerance. In conclusion, these studies have suggested that MLD-STZ-induced diabetes in female B6C3F1 mice is a useful model to evaluate drug modulation of diabetes, and that the herb formula HDDM possesses anti-diabetic effects.

Effects of Microbial Inoculants on the Fermentation, Nutrient Retention, and Aerobic Stability of Barley Silage

  • Zahiroddini, H.;Baah, J.;McAllister, T.A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권10호
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    • pp.1429-1436
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    • 2006
  • Fermentation characteristics, nutrient retention and aerobic stability of barley silages prepared using 6 commercial inoculants were evaluated using 126 mini-silos (3-L) in a completely randomized design. Whole barley forage was chopped, wilted to 39% DM and treated with water (control, S) or one of six inoculants: A (containing Lactobacillus plantarum); B (L. plantarum and Enterococcus faecium); C (L. plantarum and Pediococcus cerevisiae); D (L. plantarum, Pediococcus pentosaceus and Propionibacterium freudenreichii, plus hydrolytic enzymes); E (Lactobacillus buchneri plus hydrolytic enzymes); F (L. buchneri and P. pentosaceus plus hydrolytic enzymes). Samples of treated forage were collected for analysis at the time of ensiling, and then 18 silos of each treatment were filled, capped and weighed. Triplicate silos were weighed and opened after 1, 3, 5, 7, 33, and 61 d. On d 61, $400{\pm}5g$ of material from each silo was placed in 1-L styrofoam containers, covered with cheesecloth and held at room temperature. Silage temperature was recorded hourly for 14 d via implanted thermocouple probes. Chemical composition of the forage at ensiling was consistent with previously reported values. At d 61, pH was lowest (p<0.01) in silage S. Ammonia-N was lower (p<0.05) in silage A than in silages S, B, E, or F. Compared to pre-ensiling values, water soluble carbohydrate concentrations were elevated in silages S, A, B, C and D, and decreased in E and F. Lactic acid concentrations were similar (p>0.10) across treatments. Acetic acid levels were highest (p<0.01) in silage E and lowest (p<0.01) in silage D. Recovery of DM was lower (p<0.01) in silage F than in silages S, A, B, C, or D. On d 61, yeasts were most numerous (p<0.01) in silage D, which was the only silage in which temperature rose more than $2^{\circ}C$ above ambient during aerobic exposure. Silage D also had the highest (p<0.01) pH and ADIN content after aerobic exposure. Lactic acid and WSC content of silage D decreased dramatically during the 14-d aerobic exposure period. Yeast counts (at d 14 of exposure) were lowest (p<0.01) in silages E and F. In general, the commercial inoculants did not appear to enhance the fermentation of barley silage to any appreciable extent in laboratory silos.

경주에서 분리된 탄저균에 대한 연구 (Investigation on Bacillus anthracis isolated from Kyong-Ju)

  • 이준규;이은미;차우양;김정화;김영환;이양수;김우현;정종식
    • 한국동물위생학회지
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    • 제18권1호
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    • pp.41-56
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    • 1995
  • The present study was conducted to investigate results of B. anthracis isolated from Anthrax in the Kyong-Ju of Feb. 12. 1994. 1. In biochemical feature, B. anthracis was a gram-positive rod, non-motility, sporulation, capsulation. It was positive in gelatinase, starch hydrolysis, glucose. But negative in urease, arabinose, mannitol, xylose. 2. B. anthracis grew well on B4 Br A TSA after incubation for 24 hours. The organisim grew well on BA, Br. A, NA, TSA after incubation for 72 hours. The media grew well on Br A instead of BA. 3. On 5% blood agar by laboratory animal, ${\beta}$ -hemolysis was produced from 36 hours to 48 hours incubation. There was perfect ${\beta}$-hemolysis after incubation for 48 hours. On the other side ${\beta}$-hemolysis was begun on 5% goat blood agar after incubation for 60 hours. 4. In the test of antimicrobial susceptibility, B. anthracis was very sensitive to AM, CF, TE, ENR, GM, AN, DFX, S, P, TYLO, N, KM, C, E, Lins+Sp, NN, CC, CFP, CB were sensitive one by one. B. anthracis was no-sensitive to L, XNL, TIA, CL, SXT 5. B. anthracis had never sensitivity to direct inoculation of rat and chicken, after subcutanous inj. It was very sensitive to mouse and goat, hamster, guinea pig, rabbit had a sensibility one by one. 6. The dead laboratory animal which had been inoculated with B. anthracis preserved at $37^{\circ}C$ incubation, B. anthracis didn't cultivate on non-dissected animal after 80 hours but cultivate on dissected animal after 360 hours. 7. The rapidly death could cause high concentration, died from 420 after S. C. 8. The blood smeared samples of hamster from inoculation with B. anthracis, spore germinated In 37$^{\circ}C$ after 5 hours, in $32^{\circ}C$ after 6 hours, in room temperature after 9 hours, in $-4^{\circ}C$ to $-20^{\circ}C$ after 10 hours. 9. B, anthracis inoculated to laboratory animal after SC or PO. Mice and rats feces didn't cultivated with B. anthracis after SC, but did cultivated with B. anthracis after PO. 10. In the test of disinfectant, B. anthracis was high effective to $HgC1_2$, formalin, effect phenol, cresol, but non-effect NaOH, ethanol.

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