188 research outputs found

    Comparative Study of The Effects of Wind and Earthquake Loads on High-rise Buildings

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    It is very essential to consider the effects of lateral loads induced from wind and earthquakes in the design of reinforced concrete structures, especially for high-rise buildings. The Egyptian Code of Practice for Calculating Loads and Forces in Structural and Building Works, 1993 and 2003 gives simplified methods for calculating such loads. In some cases effects of earthquakes are found to be dominant and more critical than wind effects. This depends on some factors defined by codes. In this research the both effects will be studied and compared according to the Egyptian Code 1993 and 2003. The codes are reviewed for wind and earthquake analysis and discussed to show all factors affecting the design. A computer program is developed to analyze the structural buildings behavior under wind pressure defined as well as equivalent static loads for earthquakes considering all factors in the codes. Application examples for buildings with different heights, floor weights and boundary conditions for both winds and earthquakes such as the intensity of the wind pressure, the seismic zone coefficient, the importance factor, structural system factor and the soil coefficient are analyzed and discussed for the purpose of comparison. Some recommendations are suggested to improve the resistance of the structural and environmental systems of the buildings with respect to lateral loads. Finally Egyptian seismic map, tables of different shape effect and structural systems are provided to help structural designers and researches during design process

    Effect of drip irrigation circuits design and lateral line length on: II-flow velocity and velocity head

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    The objectives of the work were to study the effect of drip irrigation circuits (DIC) and lateral lines lengths (LLL) on: Flow velocity (FV) and velocity head (VH). Laboratory tests were con- ducted at Irrigation Devices and Equipments Tests Laboratory, Agricultural Engineering Research Institute, Agriculture Research Center, Giza, Egypt. The experimental design of laboratory experiments was split in randomized complete block design with three replicates. Laboratory tests carried out on three irrigation lateral lines 40, 60, 80 m (LLL1, LLL2; LLL3) under the following three drip irrigation circuits (DIC): a) one manifold for lateral lines or closed circuits with one manifold of drip irrigation system (CM1DIS); b) closed circuits with two manifolds for lateral lines (CM2DIS), and c) traditional drip irrigation system (TDIS) as a control. Concerning FV values, DIC and LLL treatments could state in the following ascending orders: TDIS \u3c CM1DIS \u3c CM2DIS and LLL1 \u3c LLL2 \u3c LLL3, respectively. FV varied from 0.593 m·sec–1 to 1.376 m·sec–1. i.e. FV \u3c 5 ft·sec–1 and this is necessary to avoid the effect of water hammer in the main and sub-main lines, but in lateral line, it can cause silt and clay precipitation problems. The differences in FV among DIC and LLL were significant at the 1% level. The effect of interaction: DIC X LLL on FV values, were significant at the 1% level. The maximum and minimum values of FV were noticed in these interactions: CM2DIS X LLL3 and TDIS X LLL1, respectively. The following ascending orders TDIS \u3c CM1DIS \u3c CM2DIS and LLL1 \u3c LLL2 \u3c LLL3 expressed their effects on VH respectively. Differences in VH among DIC and/or LLL were significant at the 1% with few exceptions. The effects of interactions: DIC X LLL on VH were significant at the 1% level in some cases. The maximum and minimum values of VH were found in the interactions: CM2DIS X LLL3 and TDIS X LLL1, respectively

    Effects of drip irrigation circuit design and lateral line lengths: I—On pressure and friction loss

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    Laboratory tests were conducted at the Irrigation Devices and Equipment’s Test Laboratory, Agricultural Engineering Research Institute, Agriculture Research Center, Giza, Egypt. The experimental design of laboratory experiments was split in randomized complete block design with three replicates. Laboratory tests carried out on three irrigation lateral lines of 40, 60, 80 m under the following three drip irrigation circuit (DIC) designs; 1) one manifold for lateral lines or closed circuits with one manifold of drip irrigation system (CM1DIS); 2) closed circuits with two manifolds for lateral lines (CM2DIS), and 3) traditional drip irrigation system (TDIS) as a control. The aims of the work were to study the effect of drip irrigation circuits (DIC) and lateral lines lengths (LLL; where): (LLL1 = 40 m, LLL2 = 60 m, and LLL3 = 80 m) on pressure head (PH) and friction loss (FL). Regarding to LLL and according to PH values, DIC designs could be ranked in the following ascending order: TDIS \u3c CM1DIS \u3c CM2DIS. The differences in PH among DIC de-signs were significant at the 1% level. The de-pressive effects of LLL on PH could be ranked in the following ascending order: LLL1 \u3c LLL2 ≤ LLL3. Differences in PH among LLL treatments were significant at the 1% level except that be-tween LLL2 and LLL3. The effects of interactions among: DIC × LLL on PH were significant at the 1% level with some exceptions. The highest value of PH (9.5 m) and the lowest one (6.05 m) were achieved in the interactions of CM2DIS × LLL1 and TDIS × LLL3, respectively. The shapes of the energy gradient lines were affected by DIC and LLL treatments used through their effect on ΔH/H ratio. However, they followed similar trends. According to the FL values, DIC and LLL treatments could be ranked in the following descending orders TDIS \u3e CM1DIS \u3e CM2DIS and LLL1 \u3e LLL2 \u3e LLL3. The differences in FL among DIC and LLL were significant and the effects of interactions among DIC × LLL on FL were significant at the 1% level. The maximum and mi- nimum values of FL were obtained in the inter-actions: TDIS × LLL3 and CM2DIS × LLL1, respectively. Therefore, the CM2DIS system is recommended for use where technically feasible

    Проблема достоверности научного знания

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    Знание в самом общем виде можно определить как верное отражение в сознании человека явлений материального и духовного мира и, в частности, многообразных явлений общественной жизни

    Prevalence and Determinants of Anemia in Pregnancy, Sana’a, Yemen

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    Anemia is a global public health problem in both developing and developed countries, especially among pregnant women. The aim of the study was to estimate the prevalence of anemia among pregnant women in Sana'a governorate, Yemen, and to identify the determinants contributing to it, and to assess knowledge regarding it. The study was conducted using a cross-sectional approach. It included 360 pregnant women attending the maternity clinics of maternity hospitals. A predesigned structured interviewing questionnaire was used to collect data from the pregnant women. Laboratory investigations were done. The prevalence of anemia was found to be 40.3%, and was higher among females aged 35 to less than 45 years, those with poor income and poor nutritional level. The risk of anemia increased with the gestational age, gravidity, decreased birth spacing, drinking tea and coffee after meals, decreased intake of proteins and low level of knowledge and income. The binary logistic regression model indicated a significant impact of the education and occupation on the level of knowledge of pregnant women. Anemia was found out to be a severe public health problem among pregnant women in Yemen. Identified risk factors should be considered for its prevention and control

    Energy and water saving by using modified closed circuits of drip irrigation system

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    The aim of this research was determine the energy and water use efficiencies under the modification of closed circuit drip irrigation systems designs. Field experiments carried out on transgenic maize (GDH, LL3), (Zea Mays crop) under two types of closed circuits: a) One manifold for lateral lines or Closed circuits with One Manifold of Drip Irrigation System (CM1DIS); b) Closed circuits with Two Manifolds of Drip Irrigation System (CM2DIS), and c) Traditional Drip Irrigation System (TDIS) as a control. Three lengths of lateral lines were used, 40, 60, and 80 meters. PE tubes lateral lines: 16 mm diameter; 30 cm emitters distance, and GR built-in emitters 4 lph when operating pressure 1 bar under Two levels slope conditions 0% and 2%. Experiments were conducted at the Agric. Res. Fields., Soil and Plant & Agric. System Dept., Agric. Faculty, Southern Illinois University, Carbondale (SIUC), Illinois, USA. Under 0% level slope when using CM2DIS the increase percent of Energy Use Efficiency (EUE) were 32.27, 33.21, and 34.37% whereas with CM1DIS were 30.84, 28.96, and 27.45% On the other hand when level slope 2% were with CM2DIS 31.57, 33.14, and 34.25 while CM1DIS were 30.15, 28.98, and 27.53 under lateral lengths 40, 60 and 80 m respectively relative to TDIS. Water Use Efficiency (WUE) when level slope 0% under CM2DIS were 1.67, 1.18, and 0.87 kg/m3 compared to 1.65, 1.16, and 0.86 kg/m3 with CM1DIS and 1.35, 1.04, and 0.75 kg/m3 with TDIS whereas with level slope 2% when using CM2DIS were 1.76, 1.29, and 0.84 kg/m3 compared to 1.77, 1.30, and 0.87 kg/m3 with CM1DIS and 1.41, 1.12, and 0.76 kg/m3 (for lateral lengths 40, 60, and 80 meters respectively). Water saving percent varied widely within individual lateral lengths and between circuit types relative to TDIS. Under slope 0% level CM2DIS water saving percent values were 19.26, 12.48, and 14.03%; with CM1DIS they were 18.51, 10.50, and 12.78%; and under slope level 2% with CM2DIS they were 19.93, 13.26, and 10.38% and CM1DIS were 20.49, 13.96, and 13.23% (for lateral lengths 40, 60, 80 meters respectively). The energy use efficiency and water saving were observed under CM2DIS and CM1DIS when using the shortest lateral length 40 meters, then lateral length 60 meters, while the lowest value was observed when using lateral length 80 meters this result depends on the physical and hydraulic characteristics of the emitters, lateral line uniformity, and friction losses. CM2DIS was more energy use efficiency, EUE, water saving, and WUE than either CM1DIS or TDIS

    Modification of water application uniformity among closed circuit trickle irrigation systems

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    The aim of this research was determine the ma- ximum application uniformity of closed circuit trickle irrigation systems designs. Laboratory tests carried out for Two types of closed circuits: a) One manifold for lateral lines or Closed cir-cuits with One Manifold of Trikle Irrigation Sys-tem (COMTIS); b) Closed circuits with Two Manifolds of Trikle Irrigation System (CTMTIS), and c) Traditional Trikle Irrigation System (TTIS) as a control. Three lengths of lateral lines were used, 40, 60, and 80 meters. PE tubes lateral lines: 16 mm diameter; 30 cm emitters distance, and GR built-in emitters 4 lph when operating pressure 1 bar. Experiments were conducted at the Agric. Eng. Res. Inst., ARC, MALR, Egypt. With COMTIS the emitter flow rate was 4.07, 3.51, and 3.59 lph compared to 4.18, 3.72, and 3.71 lph with CTMTIS and 3.21, 2.6, and 2.16 lph with TTIS (lateral lengths 40, 60, and 80 meters respec-tively). Uniformity varied widely within individual lateral lengths and between circuit types. Under CTMTIS uniformity values were 97.74, 95.14, and 92.03 %; with COMTIS they were 95.73, 89.45, and 83.25 %; and with TTIS they were 88.27, 84.73, and 80.53 % (for lateral lengths 40, 60, 80 meters respectively). The greatest uniformity was observed under CTMTIS and COMTIS when using the shortest lateral length 40 meters, then lateral length 60 meters, while the lowest value was observed when using lateral length 80 me-ters this result depends on the physical and hy-draulic characteristics of the emitter and lateral line. CTMTIS was more uniform than either COMTIS or TTIS. Friction losses were decreased with CTMTIS in the emitter laterals at lengths 40 meters compared to TTIS and COMTIS. There-fore, differences may be related to increased friction losses when using TDIS and COMDIS

    Brucella spp. infection in large ruminants in an endemic area of Egypt: cross-sectional study investigating seroprevalence, risk factors and livestock owner's knowledge, attitudes and practices (KAPs)

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    <p>Abstract</p> <p>Background</p> <p>Brucellosis is regarded as one of the major zoonotic infections worldwide. It was first reported in Egypt in 1939 and is now endemic, the predominate species of <it>Brucella </it>in cattle and buffalo in Egypt is <it>B. melitensis</it>. The aim of the study was to estimate seroprevalence of <it>Brucella </it>spp. in cattle and buffalo reared in households in an Egyptian village, identify risk factors for animals testing seropositive and to assess the knowledge, attitudes and practices (KAPs) of livestock owners with regards to brucellosis.</p> <p>Methods</p> <p>A cross-sectional study was carried out in a village in Menufiya Governorate of Egypt. In June and July 2009, 107 households were selected using systematic sample and all lactating cattle and buffalo present in the household were sampled and tested for antibodies against <it>Brucella </it>spp. In addition, a questionnaire collecting information on potential risk factors for <it>Brucella </it>spp. infection in cattle and buffalo was administered to the household member responsible for rearing the livestock. Between December 2009 and February 2010 households were revisited and a second questionnaire regarding KAPs associated with brucellosis was administered.</p> <p>Results</p> <p>True individual and household seroprevalence were estimated to be 11.0% (95% CI: 3.06% to 18.4%) and 15.5% (95% CI: 6.61% to 24.7%), respectively. Cattle and buffalo kept in a household with sheep and goats had 6.32 (95% CI: 1.44 to 27.9) times the odds of testing seropositive for <it>Brucella </it>spp., compared to cattle and buffalo that were not. Most participants in the study stated that livestock owners assist in the parturition of ruminants without wearing gloves and that some farmers sell animals which they suspect are <it>Brucella </it>infected to butchers or at market. Many participants made their livestock's milk into cheese and other dairy products without pasteurising it.</p> <p>Conclusions</p> <p>Brucellosis was endemic at high levels, in the current study. Although livestock owners had good general knowledge of brucellosis, they still appeared to participate in high-risk behaviours, which may contribute to the high seroprevalence in the area. Veterinarians, public health authorities and other community leaders need to collaborate to control the disease in animals and to manage the risk of human exposure.</p
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