Cooperation Through Education: How Southern West Bank, Palestine, Can Be Developed Through Agricultural Engineering

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is an Invited Paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 4 (2002): A. Tamimi. Cooperation Through Education: How Southern West Bank, Palestine, Can Be Developed Through Agricultural Engineering. Vol. IV. September 2002

Penyelesaian Persamaan Duffing Osilator Pada Aplikasi Weak Signal Detection Menggunakan Metode Averaging

Pada persamaan diferensial terdapat klasifikasi yaitu persamaan diferensial linear dan persamaan diferensial tak linear. Salah satu contoh dari persamaan diferensial tak linear yaitu persamaan Duffing. Persamaan Duffing adalah persamaan tak linear yang menggambarkan osilator dengan ketaklinearan pangkat tiga. Persamaan Duffing digunakan oleh banyak peneliti sebagai suatu pendekatan model banyak sistem fisik, persamaan ini memperlihatkan satu jangkauan sangat luas dari perilaku dalam sistem dinamika tak linear. Salah satu aplikasi pada persamaan Duffing tersebut adalah weak signal detection. Pada penelitian ini akan dibahas model persamaan Duffing osilator pada aplikasi weak signal detection kemudian diselesaikan menggunakan metode aproksimasi salah satunya yaitu metode Averaging. Dari hasil penelitian diperoleh model persamaan Duffing osilator pada aplikasi weak signal detection serta solusi aproksimasi dari model persamaan Duffing osilator pada aplikasi weak signal detection menggunakan metode Averaging dengan nilai parameter yang berbeda-beda yang solusinya dibandingkan dengan metode numerik yaitu metode Runge Kutta orde empat. Hasil yang diperoleh kemudian divisualisasikan menggunakan program Maple-12.On the differential equations there is classificaton i.e linear differential equations and nonlinear differential equations. One example of nonlinear differential equations is Duffing equation. Duffing equation is used by many researchers as a model of physical systems approach, this equation shows a very wide range of behavior in nonlinear dynamics system. One of the applications on the Duffing equation is weak signal detection. This research will be discussed Duffing oscillator equation model in weak signal detection applications then solved using approximation methods one of which is the averaging method. From the research results obtained model equation of Duffing oscillator in weak signal detection applications, and approximate solution of the model equation of Duffing oscillator in weak signal detection applications using the averaging method with varying parameter values and its solution compared with the numerical method that is fourth order of Runge Kutta method. The obtained of results then visualized using Maple-12 program

Evaluation of FRP concrete compression member under repeated load and harsh environment

Strengthening and rehabilitation have been increasingly applied in many structures to improve their capacity and serviceability. Fiber Reinforced Polymer (FRP) materials are universally known for their ability to improve the load capacity of damaged structural elements because of their high linear-elastic behavior. However, enhancing the capacity of structural elements that are exposed to repeated load coupled with harsh environment is an area that requires further investigation. This research focused on experimental analysis of the behavior and response of confined and unconfined concrete compression members (300mm x 150mm) under repeated load while exposed to 1440 cycles of seawater splash zone in United Arab Emirates (UAE). Confining concrete compression members with Carbon Fiber Reinforced Polymer (CFRP) and Glass Fiber Reinforced Polymer (GFRP) sheets have increased the load capacity compared to the control sample at room temperature by 110% and 84%, respectively. Results showed that the average value of compressive strength for the confined concrete exposed to sea water splash zone conditions for CFRP and GFRP specimens has decreased by 33% and 23%, respectively, compared to the confined concrete in the room temperature. However, GFRP specimens showed higher performance in compressive strength under sea water splash zone than those of the CFRP specimens. Different mode of failures such as delamination, de-bonding and combination of such modes were observed and related to various exposure factors and mechanical properties

Pengembangan Handout Fisika Berbasis Cultural Pada Pembelajaran Ipa-fisika Di SMP

The purpose of this research was to produce of learning materials in the form of handout cultural base which valid and good category to sains(physics) learning in junior high school. The type of this research is development with 4D developt design by Thiagarajan. The method to data collection is validation, post-test, questionnaire, and documentation. The method to define simple area is a simple random sampling. Product from this research is handout with validation quality 4,2 from validators, students learning outcomes to state clear classical 75% and students have positive responds to development product with responds quality from three aspect more 50%, with 86,12% to be interested, 94,44% to simple understend statment and 98,15% statment very interest.The conclusion from this research is handout of Physics with cultural base have a good categorized and it's can to use in sains(physics) learning in junior high school

Microstructure and mechanical properties of Al-1050 during incremental ECAP

Incremental ECAP is a new method of ECAP process were the severe shear deformation is incrementally applied on the sample resulting in grain refining and new texture developing. The fundamental objective of the present work is an observation of effect of different passes of I-ECAP on microstructure and mechanical properties of AA1050 billet. To that end, 8 pass of I-ECAP have been carried out using Bc route and microstructure evolution and mechanical properties of the I-ECAPed samples have been studied. The EBSD and TEM analyses indicates that I-ECAP is as capable as conventional ECAP to grain refinements and a UFG structure is resulted after I-ECAP cycles. Tensile testing and hardness measurements indicates that mechanical properties of the Al-1050 billets increases dramatically by increasing the I-ECAP passes

Modelling the Portevin-Le Chatelier effects in aluminium alloys

Plastic deformation processes are among the most demanding processes in manufacturing causing different microstructure feature in materials. A number of various dislocation patterns can be induced by plastic strain under different conditions. A serrated yielding/jerky flow in some dilute alloys like aluminium-magnesium alloys during plastic deformation is a well-known phenomenon under certain regimes of strain rate and temperature reported in a significant number of works. The serrated features in these materials are so-called the Portevin-Le Chatelier effects. The occurrence of these undesirable effects is due to the interaction between solute atoms and mobile dislocation during the plastic deformation which is known as dynamic strain ageing. There are a significant number of theoretical and numerical investigations that have been focused on describing the serrated behaviour of these materials during plastic deformation. Hence, the fundamental objective of this paper is a general review of different constitutive modelling in regards with this feature. The typical material models and new constitutive models describing this feature are presented. In addition, applications of the models are provided indicating their advantages and disadvantages

Crystal structure of 5-(adamantan-1-yl)-3-= (4-chloroanilino)methyl-2,3-dihydro-1,3,4-oxadiazole-2-thione, C19H22ClN3OS

Abstract C19H22ClN3OS, orthorhombic, P212121 (no. 19), a = 7.0418(2) Å, b = 10.8802(3) Å, c = 23.5506(6) Å, V = 1804.36(8) Å3, Z = 4, R gt (F) = 0.0413, wR ref (F 2 ) = 0.1110, T = 100 K.</jats:p

Alcohol Intake Between Menarche and First Pregnancy: A Prospective Study of Breast Cancer Risk

Background: Adult alcohol consumption during the previous year is related to breast cancer risk. Breast tissue is particularly susceptible to carcinogens between menarche and first full-term pregnancy. No study has characterized the contribution of alcohol consumption during this interval to risks of proliferative benign breast disease (BBD) and breast cancer. Methods: We used data from 91005 parous women in the Nurses’ Health Study II who had no cancer history, completed questions on early alcohol consumption in 1989, and were followed through June 30, 2009, to analyze breast cancer risk. A subset of 60093 women who had no history of BBD or cancer in 1991 and were followed through June 30, 2001, were included in the analysis of proliferative BBD. Relative risks (RRs) were estimated using Cox proportional hazard regression. Results: We identified 1609 breast cancer cases and 970 proliferative BBD cases confirmed by central histology review. Alcohol consumption between menarche and first pregnancy, adjusted for drinking after first pregnancy, was associated with risks of breast cancer (RR = 1.11 per 10g/day intake; 95% confidence interval [CI] = 1.00 to 1.23) and proliferative BBD (RR = 1.16 per 10g/day intake; 95% CI = 1.02 to 1.32). Drinking after first pregnancy had a similar risk for breast cancer (RR = 1.09 per 10g/day intake; 95% CI = 0.96 to 1.23) but not for BBD. The association between drinking before first pregnancy and breast neoplasia appeared to be stronger with longer menarche to first pregnancy intervals. Conclusions: Alcohol consumption before first pregnancy was consistently associated with increased risks of proliferative BBD and breast cancer

Survival analysis modeling with hidden censoring

There are well-established survival analysis methodologies for data sets that are complete, with accurate information on censoring. But what if they are not complete? In this article we consider how to analyze cases where “hidden censoring” occurs, where individuals have effectively left the study but the hospital is unaware of this. We develop a new Markov chain-based methodology for generating survival curves and hazard functions, and demonstrate this using a breast cancer data set from the Kurdistan region of Iraq