Static and Seismic Performance of Geosynthetics-Strengthened Pile Foundations

Geosynthetic reinforcement in earth structures has been used extensively over the last two decades. Extensive research has been carried out to investigate solutions to enhance the lateral stability of pile foundations. This research is motivated by the need to install piles in sites characterized by soft subsurface soil conditions, and often times, in seismic active areas. This research work explores an innovative use of geosynthetics to enhance the lateral performance of pile foundations. The static and seismic soil-structure-interaction behaviors of geosynthetics-reinforced pile foundation systems were evaluated using a series of reduced scale physical model tests performed on a shaking table in a 1G environment. A laminar shear box containing a pile foundation model supporting a single degree of freedom structure installed in different soil bed models was used in the experiments. The soil models included: a layer of synthetic clay (Modified Glyben) underlain by a sand layer (simulating a base case of soft soil); a layer of synthetic clay sandwiched between a sand layer and an aggregate layer (simulating the case of conventional ground replacement for the top soft soil); and a layer of synthetic clay sandwiched between a sand layer and a geosynthetic-reinforced aggregate layer (simulating the case of ground replacement of the top soft soil combined with geosynthetic reinforcement using a microgrid mesh). A series of sine-sweep, harmonic and scaled earthquake tests have been performed to identify the amplification and resonance conditions of the foundation system and to identify various aspects of seismic-soil-pile-geosynthetic reinforcement interaction effects. Lateral static load tests of this system were performed using a one directional load system that was fixed on the laminar shear box. The dynamic and static tests were simulated employing numerical models developed using the finite element program Plaxis 3D. The results of both static and dynamic tests showed that the microgrid reinforcement improved the lateral performance of the pile foundation and reduced the vibration amplitudes of the supported structure. The numerical analysis results were in close agreement with the dynamic and static experimental results. The results of a parametric study for the investigated foundation configuration and seismic loading demands showed that the requirements for engineered backfill can be reduced by more than 50% and the lateral seismic response can be reduced by 50% by using geosynthetic reinforcement

Gravity theory in SAP-geometry

The aim of the present paper is to construct a field theory in the context of absolute parallelism (Teleparallel) geometry under the assumption that the canonical connection is semi-symmetric. The field equations are formulated using a suitable Lagrangian first proposed by Mikhail and Wanas. The mathematical and physical consequences arising from the obtained field equations are investigated.Comment: 14 pages, References added and a reference updated, minor correction

Pearl millet forage productivity under sprinkler irrigation system in sandy soil

A field experiment was conducted in a private farm (30o40' N latitude, 32o15' E longitude, and 10.0 m above mean sea level), Ismailia Governorate, Egypt, during the 2020 and 2021 summer growing seasons. The aim was to study the effect of four irrigation treatments (125, 100, 75% ETo, and farmer practice) on pearl millet forage yield. Average amounts of applied irrigation water under 125, 100, 75% ETo and farmer practice were 4637, 3710, 2782, and 5950 m3/ha, respectively with respective average water consumption values of 4130, 3308, 2482, and 5302 m3/ha. Compared to the farmer practice, the saved water was 22, 38, and 53 % for the 125, 100, and 75% ETo treatments. Average water use efficiency values were 7.91, 7.55, 6.96 and 4.59 kg/m3, and average water productivity values were 7.04, 6.73, 6.21, and 4.08 kg/m3 for 125, 100, 75% ETo and farmer treatments, respectively. The Ky factor was 1.17 indicating that the pearl millet crop is moderately sensitive to water stress. Irrigating pearl millet in sandy soils with 100% ETo will save 38% of applied irrigation water, achieve water use efficiency of 7.55 green yield/m3 of water consumed, and water productivity of 6.73 kg green yield/m3 of water applied. Keywords: Pearl millet, BIS model, sprinkler system, sandy soil, water use efficiency and water productivit

Speeded Up Robust Features Descriptor for Iris Recognition Systems

اكتسبت النظم البايومترية اهتماما كبيرا لعدة تطبيقات. كان تحديد القزحية أحد أكثر التقنيات البايومترية تطوراً للمصادقة الفعالة. نظام التعرف على القزحية الحالية يقدم نتائج دقيقة وموثوق بها على أساس الصور المأخوذة بالأشعة التحت الحمراء (NIR) عندما يتم التقاط الصور في مسافة ثابتة مع تعاون المستخدم. ولكن بالنسبة لصور العين الملونة التي تم الحصول عليها تحت الطول الموجي المرئي (VW) دون التعاون بين المستخدمين، فإن كفاءة التعرف على القزحية تتأثر بسبب الضوضاء مثل صور عدم وضوح العين، و تداخل الرموش ، والانسداد  بالأجفان وغيرها. يهدف هذا العمل إلى استخدام (SURF) لاسترداد خصائص القزحية في كل من صور قزحية NIR والطيف المرئي. يتم استخدام هذا النهج وتقييمه على قواعد بيانات CASIA v1and IITD v1 كصورة قزحية NIR وUBIRIS v1 كصورة ملونة. وأظهرت النتائج معدل دقة عالية (98.1 ٪) على CASIA v1, (98.2) على IITD v1 و (83٪) على UBIRIS v1 تقييمها بالمقارنة مع الأساليب الأخرى.Biometric systems have gained significant attention for several applications. Iris identification was one of the most sophisticated biometrical techniques for effective and confident authentication. Current iris identification system offers accurate and reliable results based on near- infra -red light (NIR) images when images are taken in a restricted area with fixed-distance user cooperation. However, for the color eye images obtained under visible wavelength (VW) without cooperation between the users, the efficiency of iris recognition degrades because of noise such as eye blurring images, eye lashing, occlusion and reflection. This works aims to use Speeded up robust features Descriptor (SURF) to retrieve the iris's characteristics in both NIR iris images and visible spectrum. This approach is used and evaluated on the CASIA v1and IITD v1 databases as NIR iris image and UBIRIS v1 as color image. The evaluation results showed a high accuracy rate 98.1 % on CASIA v1, 98.2 on IITD v1 and 83% on UBIRIS v1 evaluated by comparing to the other method

Productivity of date palm as affected by irrigation in a sandy soil

A field experiment was conducted on drip irrigated date palm trees (Barhi var.) in a private farm during the 2020 and 2021 seasons to evaluate the effect of five irrigation treatments (120, 100, 80, and 60% ETo and farmer practice) on amounts of applied irrigation water (AIW), consumptive use (CU), date yield and its components, fruit quality, water use efficiency (WUE), water productivity (WP), consumed electric energy, net income, a local date crop coefficient (Kc) and yield response factor (Ky). Results revealed that, average ETo values varied between 1.26 mm/day in December and 9.85 mm/day in July. The 2–year average AIW values were 17 377, 14 546, 11 715, 8 885 and 24 680 m3/ha for the 120, 100, 80 and 60% ETo treatments and farmer practice, respectively. Highest and lowest fruit yields of 39.2 and 15.2 t/ha were recorded for the 120% and 60% ETo treatments, respectively. The WP values of the same treatments were 2.27 and 1.23 kg fruits/m3. Seasonal average Kc value of 0.74 is obtained for the 120% ETo treatment. The Ky value of 1.187 is obtained for the Barhi variety. The lowest consumed energy (64.7%) and highest net income (31.8%) were recorded for 60% and 120% ETo treatments compared with farmer practice.  Keywords: Applied water, water consumption, water use efficiency, water productivity, crop coefficient, yield response factor, energy saving, net incom

Virtual Collaborative R&D Teams in Malaysia Manufacturing SMEs

This paper presents the results of empirical research conducted during March to September 2009. The study focused on the influence of virtual research and development (R&D) teams within Malaysian manufacturing small and medium sized enterprises (SMEs). The specific objective of the study is better understanding of the application of collaborative technologies in business, to find the effective factors to assist SMEs to remain competitive in the future. The paper stresses to find an answer for a question “Is there any relationship between company size, Internet connection facility and virtuality?”. The survey data shows SMEs are now technologically capable of performing the virtual collaborative team, but the infrastructure usage is less. SMEs now have the necessary technology to begin the implementation process of collaboration tools to reduce research and development (R&D) time, costs and increase productivity. So, the manager of R&D should take the potentials of virtual teams into account

Hemothorax Following Traumatic Dobhoff Tube Insertion

Dobhoff tube is a specialized small-bore and flexible nasogastric tube that makes it more comfortable for placement than a usual nasogastric tube. Dobhoff tube insertion is commonly considered a relatively safe bedside procedure, but it is not without its associated risks. Inadvertent tracheobronchial placement of Dobhoff tube has been associated with severe complications, most notably pneumothorax. We present a rare cause of right-sided hemothorax following tracheobronchial insertion of a Dobhoff tube with a prolonged and arduous clinical course

Full Duplex Spectrum Sensing and Energy Harvesting in Cognitive Radio Networks

النطاق المزدوج (FD) للطيف الترددي في شبكات الاتصالات اللاسلكية للراديو الادراكي مع حصاد الطاقة (Full-duplex Energy Harvesting Cognitive Radio Networks “FD EHCRNs”)، والتي هي عبارة عن مزيج من تقنية الإرسال المزدوج الكامل (FD) الراديو الادراكي (CRN) وتقنية حصاد الطاقة (EH)، هي تقنية اتصالات لاسلكية جديدة الغرض منها تحسين كفاءة الطيف وتحسين كفاءة الطاقة. باستخدام النطاق المزدوج (FD) للطيف يمكن لأجهزة الراديو الادراكي عمل تحسس واستشعار متزامن لطيف الشبكات الأخرى التي يرغب في استخدام النطاق الترددي الغير مستخدم فيها وعمل نقل البيانات عبر هذا النطاق وكذلك عمل حصاد للطاقة بشكل متزامن في نفس الوقت، لذلك يمكن لنظام النطاق المزدوج في EH CRNs حل مشاكل الطيف المتقطع المتواجدة في شبكات CRN التقليدية. في هذه البحث تم تقديم اقتراح نموذج جديد من FD EHCRN من خلال التركيز على تصميم حدود الكشف (detection thresholds) ونموذج تجميع الطاقة (energy harvesting) وذلك لغرض تحسين أداء النظام الراديو الادراكي مع تحصيل الطاقة باستخدام النطاق المزدوج. مع العلم أن هذا البحث لا يسعى إلى تصميم تقنية جديدة لاستشعار الطيف من أجل EH-CRN بل إعادة تصميم واقتراح نموذج جديد لتقنية استشعار الطيف من خلال استخدام النطاق المزدوج باستخدام هوائيين. حيث تم عرض كل من التحليل الرياضي والنتائج العددية في هذا البحث.Full-duplex Energy Harvesting Cognitive Radio Networks (FD EHCRNs), which is a combination of full-duplex (FD) technique, cognitive radio (CR), and radio frequency (RF) energy harvesting technique, is a new wireless communication model to improve spectrum efficiency (SE) and energy efficiency (EE). Using FD, the Energy Harvesting Cognitive Radio Networks (EH CRN) equipment of the cognitive users can perform spectrum sensing, data transmission, and energy harvesting simultaneously. Consequently, full duplex in EH CRNs can solve the spectrum waste and transmission discontinuation problems caused by traditional CRNs. In this paper, a new proposal model for FD EHCRN is presented focusing on detection threshold design and energy harvesting model to try improving the system performance. Therefore, the purpose of this paper is to redesign the existing EHCRN and proposes a new model for spectrum sensing technique using full-duplex with only two antennas. Both mathematical analysis and numerical results are presented in this paper

BEHAVIOUR OF HIGH STRENGTH CONCRETE COMPOSITE SLABS WITH DIFFERENT END ANCHORAGES

This study is performed to investigate experimentally the behaviour of steel deck composite slabs with different end anchorages. End anchorage as a type of shear connection for composite slabs plays an important role to prevent relative slip between concrete and steel deck. The presented composite slab specimens are made of high strength concrete and loaded at a specific shear span. Objectives of this study is to evaluate experimentally load carrying capacity, end slip, mode of failure, shear bond capacity, and the end anchorage contribution to the whole composite slab behaviour. Research also presents a comparison between the experimental results and the theoretical results derived according to m-k and partial shear connection methods included in these standards (BS 5950-4:1994, CSSBI S3-2003, and EC4 EN 1994-1-1:2004)