Journal of Engineering Research and Reports <p style="text-align: justify;"><strong>Journal of Engineering Research and Reports</strong>&nbsp;<strong>(ISSN: 2582-2926)</strong> aims to publish high-quality papers in all areas&nbsp;of engineering.&nbsp;The journal also encourages the submission of useful reports of negative results. This is a quality controlled,&nbsp;OPEN&nbsp;peer-reviewed, open access INTERNATIONAL journal.</p> SCIENCEDOMAIN international en-US Journal of Engineering Research and Reports 2582-2926 Modeling Tomato Water Productivity Using Aquacrop Model in Njoro Sub County, Nakuru, Kenya <p><strong>Aims: </strong>To model tomato water productivity under deficit sub – surface drip irrigation and grass mulch densities using Aquacrop model.</p> <p><strong>Study Design:</strong> The study was factorial experimental with twelve treatments.</p> <p><strong>Place and Duration of Study:</strong> Tatton Agriculture Park, Egerton University, Nakuru, Kenya between January to May 2019.</p> <p><strong>Methodology: </strong>Tomato (<em>Lycopersicon esculentum</em> mill) crop (Tylka F1) was used to determine the effect of deficit irrigation and mulching on its productivity. Aquacrop model was calibrated to simulate the tomato yield, biomass and water productivity. Aquacrop model was used to estimate the tomato water requirements, water productivity, yield and biomass under deficit irrigation and mulching. The study was carried out on 36 experimental plots measuring 2 by 2 m with the total area under study being 144 m<sup>2</sup>.</p> <p><strong>Results:</strong> The results showed a good correlation between the actual and simulated water productivity as determined by the Nash and Sutcliffe efficiency (NSE) of 0.00, Root Mean Square Error (RMSE) (%) of 0.04 and Coefficient of determination (R<sup>2</sup>) of 0.72.</p> <p><strong>Conclusion:</strong> The study calibrated Aquacrop model for simulating tomato crop water productivity in Njoro Sub County and showed that the model is a good estimator of tomato water productivity.</p> Hellen J. Sang Raphael M. Wambua James M. Raude ##submission.copyrightStatement## 2020-02-13 2020-02-13 1 13 10.9734/jerr/2020/v10i317038 Wafer Preparation Parameter Optimization for Wafer Defects Elimination <p>In every new technology developed and introduced to the manufacturing floor, particularly in the wafer preparation, entails problems that later induce defects affecting the wafer yield. This paper discusses the optimization of wafer preparation parameters, particularly the tensionless backgrinding tape lamination and DAF cut vacuum control, that mitigates wafer yield detractors such as edge cut, kerf shift and dice pop-out. Based on the evaluation results, tensionless backgrinding lamination affects the kerf shifting and edge cutting, and with proper vacuum control to attain zero dice pop-out process.</p> B. C. Bacquian F. R. Gomez ##submission.copyrightStatement## 2020-02-15 2020-02-15 21 26 10.9734/jerr/2020/v10i317040 Draft Requirement of Two Animal - Drawn Institute for Agricultural Research (IAR) Weeders <p>Draft requirements of two animal – drawn (IAR) weeders operating on loam soil were determined in the study. The implements include a straddle row weeder and an emcot attached rotary weeder evaluated under the same soil conditions, using a pair of white Fulani breed of oxen. The animal draft requirement was first estimated from the animal ergonomics measurements. Using area of 0.054 hectare as experimental plot for each implement the draft requirement of each implement was investigated after taking soil samples for soil moisture content and bulk density determinations. The implements tested showed variation in their average draft requirement. The straddle row weeder had the highest value of 338.15 N respectively while the emcot attached rotary weeder had the lowest value of 188.12 N with 47.03%, respectively. The average soil moisture contents and bulk density were 13.0% and 1.46%/cm<sup>3</sup>, respectively.</p> Y. A. Unguwanrimi A. M. Sada G. N. Ugama H. S. Garuba A. Ugoani ##submission.copyrightStatement## 2020-02-14 2020-02-14 14 20 10.9734/jerr/2020/v10i317039