Engineering

The design of Overtaking Sight Distance (OSD) is an important aspect of highway geometrics. The current procedure of OSD design is based on deterministic methodology. Literatures available report that significant variability is associated with input parameters for OSD design. The present study deals with the characterisation of OSD variability considering different cases of input parameter variability. The Monte Carlo Simulation (MCS) technique has been adopted to derive the distributions of OSD, which are also statistically established by Chi-square Goodness of Fit (GOF) test. In all the cases, OSD is found to follow lognormal distribution. The Coefficient of Variation (COV) of OSD is found to vary from 21.45% to 22.91% and 23.66% to 25.66% for one-way traffic and two-way traffic condition respectively. Thus, the variability associated with OSD appears to be significant and necessitates probabilistic approach in OSD design. A simple design methodology has been presented for reliabi...

کیومرث در تمامی متون پهلوی و روایت‌های بازمانده از سیرالملوک ها، نخستین انسان معرفی شده است. بر اساس این متون، نسل بشر پس از کشته شدن کیومرث در مواجهه با اهریمن و با همخوابگی مشی و مشیانه ادامه می‌یابد اما شاهنامه فردوسی تنها متنی است که بر اساس آن، کیومرث نخستین پادشاه است. در شاهنامه فردوسی نبرد کیومرث با اهریمن نیز به گونه‌ای دیگر روایت شده است. مقایسه داستان کیومرث در شاهنامه و متون متأثر از سیرالملوک ها می‌تواند نتایج تازه‌ای را درباره دگرگونی و انتقال کیومرث از اسطوره به متن ادبی مانند شاهنامه روشن سازد. فزون‌متنیت ژرار ژنت رویکردی است که به ارتباط پیش‌متن و بیش‌متن می‌پردازد. در انتقال یک متن به متن دیگر تغییراتی روی می‌دهد که گشتار نامیده می‌شوند. بر مبنای مقایسه داستان کیومرث در شاهنامه و متون متأثر از سیرالملوک ها بر اساس فزون‌متنیت ژنت، گشتارهای انبساط، برش و ارزش‌گذاری مهم‌ترین عوامل دگرگونی داستان کیومرث در روایت فردوسی است که در جهت نمایشی کردن داستان، اسطوره زدایی و قابل باور کردن داستان و استحکام روابط طولی داستان با داستان‌های بعدی و هماهنگی رویدادها با نظام اعتقادی...

Research by Rogers et al (2009) and Leland et al established that flight simulator training can improve a pilot’s ability to recover a general aviation aeroplane from an in-flight upset. To reach this conclusion, they administered simulator-based and classroom-based upset-recovery training to two groups of student pilots, then compared their performance in recovering an aerobatic Decathlon aeroplane from a series of four upsets with the performance of a third group of untrained control group pilots subjected to the same upsets. We extend this result by addressing the unanswered question of how much classroom-based training as opposed to simulator-based training contributes to improving a pilot’s upset-recovery manoeuvring skills. After receiving classroom-based upset-recovery training but no simulator training, our participants were subjected to the same series of four upsets in the same Decathlon aeroplane. We then compared the performance of the classroom-trained pilots with the p...

Elektrik tekerli yukleyicinin kepce yukunu izlemek, hem operatorun hem de ekipmanin basarimini degerlendirmek bakimindan olaganustu onemlidir. Kepceyi makina ureticisi tarafindan onerilen hedef yukten az  ya da cok yuklemekten kacinmalidir. Optimum yukten az doldurmak arac uretkenligi bakimindan, cok doldurmak ise arac omru ve sagligi acisindan onerilmez. Kepcenin asiri yuklenmesi makinadan beklenen omrun ve arizalar arasi surenin kisalmasina neden olur. Ege Bolgesinde, Usak’da bir altin madeninde calisan bir LeTourneau L-1350 model (21m3) elektrik tekerlekli yukleyicinin basarimi ozellikle kepce yuku ve asiuri kepce yukleri yonunden izlenen bes vaka verilmistir. Vardiya ve gunluk kepce yuku dagilim egrileri, asiri ve kritik asiri yuk sayilari ve yuzdeleri irdelenmistir.

SUMMARYBy means of a simplified three degrees of freedom model, seismic behavior of reinforced concrete bridge piers and foundations were evaluated based on pseudo‐dynamic (PsD) tests for cases where pier strengthening and foundation strengthening are implemented. In addition, analysis based on PsD test results was conducted to investigate the influence of pier strengthening on seismic damage to the foundation. The PsD tests and the analysis show that the foundation suffers increased hysteretic response when pier strengthening is applied. The results also show that the foundation strengthening can prevent foundation damage. Copyright © 2011 John Wiley & Sons, Ltd.

Health service management plays a crucial role in human life. Blood related operations are considered as one of the important components of the health services. This paper presents a bi-objective mixed integer linear programming model for dynamic location-allocation of blood facilities that integrates strategic and tactical decisions. Due to the epistemic uncertain nature of strategic decisions, in order to cope with the inherent uncertainties, a robust possibilistic programming approach is applied to the proposed model. Finally, to test the applicability of the proposed model, sensitivity analysis and some numerical examples are being proposed.

Selecting proper location for Glycyrrhiza farms is very important in obtaining the best quality in Glycyrrhiza cultivation and at the other hand, optimized capacity planning can cause significant reduction in cultivation costs. In this paper, we consider economic factors, social effects, cultivation conditions, and environmental issues for Location Optimization and Capacity Planning (LOCP) of Glycyrrhiza. Fuzzy principal component analysis (PCA) is used to address the problem complexity. Next, we develop a multiple objective mathematical model to calculate the amount of land assigned for Glycyrrhiza cultivation in each area. Then, we use epsilon-constraint method for solving the model. Finally, the proposed approach is applied in the country of Iran. Results illustrate which provinces are the best for Glycyrrhizae cultivation. Moreover, the optimized amount of Glycyrrhizae cultivation in each area is identified, using the mathematical model suggested here.

1Assistant Professor, Dept. of EEE, MGIMT, Lucknow, UP, India 2 Assistant Professor, Dept. of EEE, MGIMT, Lucknow, UP, India 3Associate Professor, Dept. of EEE, MGIMT, Lucknow, UP, India 4UG Scholar, Dept. of EEE, MGIMT, Lucknow, UP, India ---------------------------------------------------------------------***-----------------------------------------------------------------------Abstract – Due to fast reduction of conventional energy, the power demand escalating every passing day. This paper focuses on the photo voltaic (PV) system integrated to a three phase four wire system at the distribution level with power quality improvement features. The power quality measurements and the norms followed according to the guiding principle specified in the International Electro technical Commission standard, IEC61400 are the active and reactive power variations, variation of voltages, flicker, harmonics and electrical behavior of switching operations. The paper describes overall good function...

窒化物半導体中の希土類イオンは半値幅の狭い非常にシャープな発光スペクトルを示し,発光波長の温度依存性 が小さいといった特長を持つため,環境温度に対して安定した発光デバイスへの応用が期待されている.これまで にEu添加GaN薄膜(GaN:Eu)を活性層とした赤色LEDが報告されているが,発光出力は不十分である[1].発光出 力の向上のためには発光中心となるEu濃度を増加させる必要があるが,Eu濃度の増加に伴い多結晶化やクラック, 濃度消光が顕在化し,薄膜では高濃度化が困難である [2].一方で,ナノコラム結晶[3]は結晶中に転位を含まず, 側面での歪緩和効果を有するため高濃度においても発光特性を維持することが期待できる.実際,薄膜と比較して 濃度消光が抑制される結果が得られている[4].本研究では,RF-MBE法を用いてGaN:Eu層を活性層としたナノコ ラムLEDを作製し,整流特性を得て,室温下で赤色のシャープなスペクトルを観測したので報告する. Fig. 1に本報告で作製したナノコラムLEDの構造図と断面SEM像を示す.n-Si(111)基板上に860°Cにて意図的な ドーピングをしていない n型GaNナノコラムを90分間成長し,その後,活性層となるGaN:Euナノコラムを640°C にて10分間成長させた.また活性層のEu組成の設計値は1%とした.最後にMgをドープしたp-GaNを 660°Cに て 90 分間成長させた.GaN:Eu 領域までは互いに独立したナノコラム形状が維持されており,それぞれの高さは 630nm,80nmであった.またn-GaNは平均直径50nm程度であったが,GaN:Eu層において直径80nmへと急速に 増加する様子が観測された. p-GaN領域ではMg添加と低温成長により横方向成長を促進され隣接したナノコラ ム同士が結合することで,表面において連続膜化された.表面にp-電極としてNi/Ag/Ni(5 nm/10 nm/5 nm)半透明電 極をEB蒸着させた.作製したナノコラムLEDはCuヒートシンクにおき,プローバステーションを用いることで 評価した.Fig. 2にナノコラムLEDの電圧-電流特性を示す.立ち上がり電圧4.9Vの整流特性が観測され,PN接 合が形成されていることが確認された.また直列抵抗を見積ったところ,140 ...

We use finite difference methods in the treatment of an existing system of partial differential equations that captures the dynamics of parallel honeycomb construction in a bee hive. We conduct an uncertainty analysis by calculating the partial rank correlation coefficient for the parameters to find which are most important to the outcomes of the model. We then use an eFAST method to determine both the individual and total sensitivity index for the parameters. Afterwards we examine our numerical model under varying initial conditions and parameter values, and compare ratios found from local data with the golden mean by fitting images of the combs with ellipses and then calculating the length of the major and minor axes.

Machine learning (ML) is increasingly applied to Electronic Health Records (EHRs) to solve clinical prediction tasks. Although many ML models perform promisingly, issues with model transparency and interpretability limit their adoption in clinical practice. Directly using existing explainable ML techniques in clinical settings can be challenging. Through literature surveys and collaborations with six clinicians with an average of 17 years of clinical experience, we identified three key challenges, including clinicians’ unfamiliarity with ML features, lack of contextual information, and the need for cohort-level evidence. Following an iterative design process, we further designed and developed VBridge, a visual analytics tool that seamlessly incorporates ML explanations into clinicians’ decision-making workflow. The system includes a novel hierarchical display of contribution-based feature explanations and enriched interactions that connect the dots between ML features, explanations,...

Building structures designed according to current seismic design codes should satisfy the seismic performance objectives specified in codes during big earthquake events. ASCE 7-16 specifies that risk category I and II structures should have a probability of collapse less than 10% against the maximum considered earthquake (MCE) shaking hazard. ASCE 7-16 provides four analysis methods to calculate the seismic demands on structures. In this study, 4-, 8-, 12-, and 16-story steel special moment frames (SMFs) are designed using the two most popular elastic analysis methods: the equivalent lateral force (ELF) method and the modal response spectrum analysis (RSA) method. The collapse probabilities of these structures are estimated against MCE shaking hazards according to FEMA P695. It is observed that the collapse probabilities of these structures vary according to analysis methods used for design. To improve the seismic collapse performance of SMFs, a modified method is proposed.

The welded unreinforced flange-welded web (WUF-W) connection is one of seven prequalified connections for special moment frames (SMF) specified in AISC 358-10 (2010). Previous studies reported that the cyclic behavior of WUF-W connections was strongly affected by weld access hole geometry, and some WUF-W connections did not satisfy the requirements for SMF connections. For investigating in detail the effect of access hole configurations on the cyclic behavior of WUF-W connections, this study conducts three-dimensional nonlinear finite element analyses. This study shows that the seismic behavior of WUF-W connections are strongly affected by two configuration parameters, access hole slope and length of flat portion. To satisfy the requirement for SMF connections, this study proposes a range of the access hole slope and length of flat portion for WUF-W connections considering different span-to-depth ratios, beam depths, and material types.

This report presents engineering guidance and design criteria for pavements at Army and Air Force facilities in seasonal frost areas. Design methods for controlling surface roughness and loss of subgrade strength during thawing periods are provided. Criteria for using thermal ...

Highly insulating ultrathin SiO2 films (<5 nm) were grown by means of vacuum ultraviolet photooxidation, by use of 126, 172, and 222 nm wavelength photons generated by excimer lamps. The ultrathin silicon dioxide films were grown onto the Si(001) substrate, at low temperature (<500 °C). We found that the densities of photooxidized SiO2 films were 13%–35% higher than that of thermally oxidized SiO2 film. The density profile was obtained by x-ray reflectivity and showed a remarkable decrease in the SiOx (suboxide) layer thickness at the SiO2−Si interface, in comparison with thermally oxidized conventional oxides. The Si 2p photoelectron spectrum confirmed that the SiOx layer was negligibly thin. High insulating performance of the SiO2 film was demonstrated.

In this paper, we propose an orbital-based parallelization approach for electronic structure calculations. This approach is based on finite element discretizations and iterative techniques, and permits us to carry out electronic structure calculations in an orbital separation fashion and compute eigenvalues of a class of eigenvalue problems in principle individually. It is shown by our numerical experiments that this new approach is quite efficient for all-electron calculations for a class of molecular systems.