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Tunnelling activities in urban areas are always associated with surface and subsurface ground subsidence, which may affect the stability of nearby structures and utilities. During and after tunnel construction, the surrounding building is subjected to different.deformations and strains due to immediate settlement. The constructed buildings should be able to bear the effect of change in the total, differential settlement and bending moment of raft according to the tunneling activity. The soil settlement around the tunnel and the ground movement above the tunnel should be taken in consideration too. This study focuses on the settlement of raft foundation according to tunneling activity using single and double tunnels. 2D numerical model was conducted to simulate the excessive settlement of raft according to tunneling. The effect of tunnel depth, soil consistency and spacing between double tunnels is studied. By increasing the soil cover above the tunnel crown, the settlement and bending moment of raft increases regardless the relative density of surrounding soil.

The Tiga Dam, a primary hydraulic structure in northern Nigeria, is subjected to intense hydrological stress during the rainy season, posing potential risks to its structural integrity. This study investigates the geotechnical properties and stability of the Tiga Dam in Kano State, Nigeria. Twelve soil samples from the downstream area were analyzed for specific gravity, grain size distribution, Atterberg limits, compaction parameters, permeability, and shear strength. The dam’s stability was assessed using Plaxis 2D under various reservoir conditions. Soil erodibility was evaluated using the Revised Universal Soil Loss Equation (RUSLE), and a linear regression model with noise was developed to predict soil expansion rates. The results showed heterogeneous soil properties, with specific gravity ranging from 2.11 to 2.63 and permeability from 3.40 × 10−9 to 1.49 × 10−7 m/s. Stability analysis revealed factors of safety of 1.322, 1.006, 1.002, and 1.147 for high reservoir, rapid drawdown, slow drawdown, and low reservoir conditions, respectively. The RUSLE K factor ranged from 0.055 to 0.145, indicating low to moderate soil erodibility. The expansion rate model demonstrated high accuracy (R2 = 0.989) in predicting seasonal and long-term soil expansion trends, with peak rates increasing from 16.94 mm/month in 2010–2013 to 19.45 mm/month in 2017–2020. This comprehensive analysis provides crucial insights into the Tiga Dam’s geotechnical behavior, highlighting potential vulnerabilities and the need for targeted management strategies to ensure long-term stability and safety.

Landslides cause significant economic losses and casualties worldwide. However, robust prediction remains challenging due to the complexity of geological factors contributing to slope stability. Advanced correlation analysis methods can improve prediction capabilities. This study aimed to develop a novel landslide prediction approach that combines numerical modeling and correlation analysis (Spearman rho and Kendall tau) to improve displacement-based failure prediction. Simulations generate multi-location displacement data sets on soil and rock slopes under incremental stability reductions. Targeted monitoring points profile local displacement responses. Statistical analyses, including mean/variance and Spearman/Kendall correlations, quantified displacement-stability relationships. For the homogeneous soil slope, monitoring point 2 of the middle section of the slope showed a mean horizontal displacement of 17.65 mm and a mean vertical displacement of 9.72 mm under stability reduction. Spearman’s rho correlation coefficients ranged from 0.31 to 0.76, while Kendall’s tau values ranged from 0.29 to 0.64, indicating variable displacement–stability relationships. The joint rock slope model had strong positive total displacement correlations (Spearman’s and Kendall’s correlation ranges of +1.0 and −1.0) at most points. Horizontal and vertical displacements reached mean maxima of 44.13 mm and 22.17 mm, respectively, at the unstable point 2 of the center section of the slope. The advanced correlation analysis techniques provided superior identification of parameters affecting slope stability compared to standard methods. The generated predictive model dramatically improves landslide prediction capability, allowing preventive measures to be taken to mitigate future losses through this new approach.

Abstract Multi‐level inverters are widely used in high‐voltage and high‐power applications due to the increasing demand for renewable energy. This study proposes a novel single‐phase reduced switch multi‐level inverter topology that generates 11 levels of output voltage steps, operates in asymmetric mode, and uses fewer power electronic switches with efficient switching control. To optimize the inverter's performance, Moth Flame Optimization (MFO), Particle Swarm Optimization (PSO), and Whale Optimization Technique (WOA) are utilized to apply the selective harmonic elimination technique. The proposed circuit is implemented in PSIM software using optimized switching angles, and the fitness functions and switching angles for the three optimizers are evaluated and reported. The inverter's performance at optimal modulation points for the three optimizers is computed and analyzed, with the Total Harmonic Distortion (THD) measured at 0.82 modulation point before and after filtering. Results show that MFO outperforms PSO and WOA with the lowest THD values of 0.85% and 0.78%, respectively; therefore, complying with the IEEE 519 standard. The experimental validation of MFO's superiority is performed using the Typhoon HIL‐402 hardware device. This study provides a promising solution for the design and optimization of multi‐level inverters, paving the way for more efficient and reliable renewable energy systems.

In this paper, a new cladding process is proposed and implemented on a bimetallic tube of copper and aluminum. Obtaining a good mechanical bond between the tube’s layers using simple setup components with low required process force and without using heating are the most distinguishing feature of this study. The objective of this paper is to study the effect of using three different spherical tipped punch diameters (21 mm, 21.6 mm, and 22 mm) on the cladding process. A spherical punch with a slightly enlarged spherical tip was pressed into the clad tube. To study the dynamical analysis of the developed process, an FE model was developed using ANSYS workbench®. The bonding of an AL6082T6 Aluminum tube (as the clad tube) to a pure copper tube (as the base tube) was studied. FE analysis results showed that increasing ball tipped punch diameter leads to an increase in the required process force, the deformation magnitude, the equivalent plastic strain, the maximum principal stress, and the maximum principal elastic strain values. The required process force was measured experimentally and by FE simulation for the three different ball tipped punch diameters. The average values of the FE process forces were found to be 21 KN, 39 KN and 48 KN respectively for the mentioned diameters, while experimentally the average forces values were found to be 13.3 KN, 33 KN and 39 KN for the mentioned diameters, respectively. A 10 KN force was required to dismantle the bimetallic tube layers using shear punch test.

In this article, an enhanced maximum power point tracking (MPPT) technique for photovoltaic (PV) systems is presented. The proposed MPPT is designed for fast-changing operating conditions, where the conventional methods suffer from divergence (drift) under such conditions. Mainly, the reason for divergence in the traditional methods is the confusion between power change due to the perturbation of the control parameter and power variation because of the atmospheric conditions. Therefore, and to differentiate between these cases, additional control loops are added to the conventional perturb and observe (P&O) method to enhance its behavior. Furthermore, in our suggested scheme, the finite-set model predictive control (FS-MPC) principle is integrated with the proposed algorithm to enhance its transient performance. However, and to decrease the computational effort, the prediction stage (including cost function calculation) is eliminated. The suggested methodology is compared with the conventional FS-MPC for evaluation using experimental results at different atmospheric conditions (static and dynamic radiation).

This study investigates the alterations in the ratios of components such as class C fly ash (FA), blast furnace slag (BFS), and waste stone powder (WSP) types of limestone powder (LP) used in the production of geopolymer concrete. These components are meticulously examined concerning the physical and mechanical attributes of geopolymer concrete. Using the mixture-design method, 10 different mixing ratios were determined using FA, BFS, and LP, and experimental research on the mechanical attributes and workability of geopolymer mortar is presented. A series of experimental tests, including tests for compressive strength, impact strength, setting time, flow table, flexural strength, and water absorption, were carried out on the geopolymer mortars that were made using FA, BFS, and LP, to investigate and enhance their overall performance. The experimental study aimed to ascertain the extent to which variations in the materials used in the formation of geopolymer mortar affected its mechanical and physical properties. To achieve this objective, certain parameters for geopolymer mortar formulation were fixed, according to the literature (molarity: 10; aggregate/binder ratio: 2.5; plasticizer ratio: 2%; sodium silicate (SS)/sodium hydroxide (SH): 1.5; additional water content: 14.5%; alkali activators/binder: 0.5). Subsequently, mortars were produced according to the 10 different mixing ratios determined by the mixture-design method, and the experiments were completed. The samples of the 10 different mixes were subjected to air curing at an ambient temperature (23 °C ± 2 °C) for 28 days. Following the curing period, the tests revealed that mix No. 9 exhibited the best compressive, flexural, and impact strengths, while mix No. 10 demonstrated superior workability of geopolymer mortar. It was shown that impact, compressive, and flexural strength values decreased as the ratios of FA and LP increased. In contrast, the increases in the ratios of FA and LP positively influenced the workability of geopolymer mortar.

a 3D numerical model done by PLAXIS 3D software was used to predict the behavior of floating under-reamed piles subjected to compression load in medium clay. The study focuses on the effect of pile geometrical features on bearing load such as bulb spacing, bulb diameter, and the bulbs number compared with the conventional pile. Considering medium clay as a single layer in the analysis with the cohesion of 38 kN/m², the comparison of results for multi under-reamed pile compared with a conventional pile takes into account the bulbs number ranging from one to three, bulb diameter ratio (Du/D) from 1.5 to 2.5, the spacing ratio (S/D) from center to center of bulb from 2 to 8 and bulb location, the pile length is constant in this study. The linear elastic constitutive model was considered to simulate the pile material, and the Mohr-Coulomb model was chosen to represent the clay surrounding the pile. The results of the numerical model show that when the bulb diameter ratio becomes 2.50, the bearing load increases by 50.31 % for an under-reamed pile with a single bulb compared with a pile without a bulb.Also, using an under-reamed pile with a bulb diameter ratio (Du/D = 2.5), bulb spacing ratio (S/D = 8), and when the bulbs number were three, the bearing load increased by 165.50% compared with a pile without a bulb.

Artificial Intelligence (AI)-based ChatGPT developed by OpenAI is now widely accepted in several fields, including education. Students can learn about ideas and theories by using this technology while generating content with it. ChatGPT is built on State of the Art (SOA), like Deep Learning (DL), Natural Language Processing (NLP), and Machine Learning (ML), an extrapolation of a class of ML-NLP models known as Large Language Model (LLMs). It may be used to automate test and assignment grading, giving instructors more time to concentrate on instruction. This technology can be utilised to customise learning for kids, enabling them to focus more intently on the subject matter and critical thinking ChatGPT is an excellent tool for language lessons since it can translate text from one language to another. It may provide lists of vocabulary terms and meanings, assisting students in developing their language proficiency with resources. Personalised learning opportunities are one of ChatGPT’s significant applications in the classroom. This might include creating educational resources and content tailored to a student’s unique interests, skills, and learning goals. This paper discusses the need for ChatGPT and the significant features of ChatGPT in the education system. Further, it identifies and discusses the significant applications of ChatGPT in education. Using ChatGPT, educators may design lessons and instructional materials specific to each student’s requirements and skills based on current trends. Students may work at their speed and concentrate on the areas where they need the most support, resulting in a more effective and efficient learning environment. Both instructors and students may profit significantly from using ChatGPT in the classroom. Instructors may save time on numerous duties by using this technology. In future, ChatGPT will become a powerful tool for enhancing students’ and teachers’ experience.

Soil stabilization is a critical step in numerous engineering projects, preventing soil erosion, increasing soil strength, and reducing the risk of subsidence. Due to its inexpensive cost and potential environmental benefits, waste materials, such as waste marble powder (WMP), have been used as additives for soil stabilization in recent years. This study investigates waste marble powder’s effects on unconfined compressive strength (UCS) and clayey soil’s ultrasonic pulse velocity (UPV) at different water contents and curing times, and artificial neural networks (ANNs) are also used to predict the UCS and UPV values based on three input variables (percentage of waste marble dust, curing time, and moisture content). Geo-engineering experiments (Atterberg limits, compaction characteristics, specific gravity, UCS, and UPV) and analytical methods (ANNs) are used. The study results indicate that the soil is high-plasticity clay (CH) using the Unified Soil Classification System (USCS), and adding waste marble powder (WMP) can significantly improve the UCS and UPV of clay soils, especially at optimal water content, curing times of 28 days, and 60% WMP. It is found that the ANN models accurately predict the UCS and UPV values with high correlation coefficients approaching 1. In addition, this study shows that the optimum water content and curing time for stabilized clay soils depend on the grade and amount of waste marble powder utilized. Overall, the study demonstrates the potential of waste marble dust as a soil stabilization additive and the usefulness of ANNs in predicting UCS and UPV values. This study’s results are relevant to engineers and researchers working on soil stabilization projects, such as foundations and backfills. They can contribute to the development of sustainable and cost-effective soil stabilization solutions.

Valvular diseases may affect one or more of the cardiac valves, which may need to be replaced or restored for effective treatment. The surgical procedure can be guided by a patient-specific and dynamic model containing information complementary to the 2D/3D static images of the valves. To this end, in this study a novel automated model-free aortic valve segmentation method is presented, and its performance is evaluated against expert annotations over conventional contrast-enhanced ECG-gated multislice CT data of the aortic valve at its closed position. Detailed evaluation of the proposed method in 19 real cases revealed an encouraging performance of 3D region growing over Hessian based approach but also demonstrated the complexity of the problem.

Lightning strike causes a large lightning voltage injection into grid-connected PV systems at the point between inverter and transformer. The overvoltage resulting from the lightning-impulse voltage is a major concern for the multiple expensive electrical devices of the grid-connected PV system and to be studied in depth in order to decrease the damage caused by this overvoltage. In this paper, PSCAD/EMTDC software simulated the complete model of the system. In this work, the point which selected from grid-connected PV system to inject impulse lightning voltage is between transformer and inverter. In different locations of the grid-connected PV system, lightning overvoltage has been noted by injecting impulse lightning voltages. In this paper, the surge arrester is used to mitigate the lightning overvoltage on the PV array. STATCOM is used to improve voltage of the PV array. The results show that in case of using the surge arresters and STATCOM, the lightning overvoltage is mitigated.

The use of an instrumented scanning vehicle has become the center of focus for bridge health monitoring (BHM) due to its cost efficiency, mobility, and practicality. However, indirect BHM still faces challenges such as the effects of road roughness on vehicle response, which can be avoided when the vehicle is in a stationary condition. This paper proposes a baseline-free method to detect bridge damage using a stationary vehicle. The proposed method is implemented in three steps. First, the contact-point response (CPR) of the stationary vehicle is computed. Secondly, the CPR is decomposed into intrinsic mode functions (IMFs) using the variational mode decomposition (VMD) method. Finally, instantaneous amplitude (IA) of a high frequency IMF is computed. The peak represents the existence and location of the damage. A finite element model of a bridge with damage is created. The results show that the method can identify the damage location under different circumstances, such as a vehicle with and without damping, different speeds of the moving vehicle, different sizes of damage, and multiple damage. A higher speed was found to provide better visibility of damages. In addition, smaller damage was less visible than wider damage.

Bu çalışmada, Orta Anadolu’da yerel depremlerin varış zamanlarından hareketle Poisson oranı Tomografisi metodu kullanılarak üç boyutlu (3-B) hız yapısını belirlenmiştir. Bu çerçevede, toplam 27.141 adet depreme ait 109.740 adet P dalgası ve 102.934 adet S dalgası varış zamanı verisi kullanılmıştır. Depremler Boğaziçi Üniversitesi, Kandilli Rasathanesi ve Deprem Araştırma Enstitüsü’ne (KRDAE) bağlı Ulusal Pasif Hareket Sismik Ağı’na bağlı istasyonlar tarafından kaydedilmiştir. İnceleme alanında bulunan deprem istasyonları ve deprem merkez üssü dağılımı, elde edilen Vp ve Vs hız dağılımının 40 km’ye kadar güvenilir sonuç verdiğini göstermektedir. Dama tahtası (Checkerboard) çözünürlük testi ve ışın yolu dağılımları bu durumu doğrulamaktadır. Tomografik sonuçlar, Orta Anadolu’da kabuk ve üst mantoda yanal heterojenliklerin varlığına işaret etmektedir. Depremlerin bölgedeki karmaşık tektonik ve jeolojik yapıdan dolayı genel olarak sismik hızın düştüğü alanlarda oluştuğu dikkati çekmektedir. Düşük veya yüksek hız değerlerine sahip olan tüm bölgelerin gerilme enerjisi birikimi için potansiyel alanlar olduğunu görülmektedir. Elde edilen P ve S dalga hızı modelleri, Orta Anadolu'daki mevcut sismotektonik yapıyı net bir şekilde ortaya koymaktadır.

Bu çalışmada, Orta Anadolu’da yerel depremlerin varış zamanlarından hareketle Poisson oranı Tomografisi metodu kullanılarak üç boyutlu (3-B) hız yapısını belirlenmiştir. Bu çerçevede, toplam 27.141 adet depreme ait 109.740 adet P dalgası ve 102.934 adet S dalgası varış zamanı verisi kullanılmıştır. Depremler Boğaziçi Üniversitesi, Kandilli Rasathanesi ve Deprem Araştırma Enstitüsü’ne (KRDAE) bağlı Ulusal Pasif Hareket Sismik Ağı’na bağlı istasyonlar tarafından kaydedilmiştir. İnceleme alanında bulunan deprem istasyonları ve deprem merkez üssü dağılımı, elde edilen Vp ve Vs hız dağılımının 40 km’ye kadar güvenilir sonuç verdiğini göstermektedir. Dama tahtası (Checkerboard) çözünürlük testi ve ışın yolu dağılımları bu durumu doğrulamaktadır. Tomografik sonuçlar, Orta Anadolu’da kabuk ve üst mantoda yanal heterojenliklerin varlığına işaret etmektedir. Depremlerin bölgedeki karmaşık tektonik ve jeolojik yapıdan dolayı genel olarak sismik hızın düştüğü alanlarda oluştuğu dikkati çekmektedir. Düşük veya yüksek hız değerlerine sahip olan tüm bölgelerin gerilme enerjisi birikimi için potansiyel alanlar olduğunu görülmektedir. Elde edilen P ve S dalga hızı modelleri, Orta Anadolu'daki mevcut sismotektonik yapıyı net bir şekilde ortaya koymaktadır.

Bu makalede, binek ve ticari araçların bagaj hacimlerinin uluslararası standartlara göre hesaplanabilmesi için bilgisayar destekli tasarım (CAD) yazılımı içerisinde çalışan bir yerleşim algoritması geliştirilmiş, algoritma kodlanarak örnek modeller üzerinde uygulanmıştır. Dış yüzeyleri ve iç yüzeyleri verilen bagaj geometrik modeli üzerinde, ISO ve DIN standartlarında yer alan yöntem referans alarak bagaj içine konulan hacimsel blokların dik yerleşim düzenlerine göre dizilmesi gerçekleştirilmiş, maksimum sayıda bloğun sığdığı durum bagaj hacmi olarak belirlenmiştir. Bu sayede, yeni araç tasarım sürecinde zaman ve maliyet açısından önemli kazanımlar söz konusu olacak, mevcut durumda fiziksel ortamda manuel olarak yapılan ve zaman alan testler, araç tasarım sürecinde CAD ortamında daha kısa sürede gerçekleştirilebilecektir.

Bu deneysel çalışmada, spinel seramiklerin önemli bir türü olan kalsiyum aluminat (CaAl2O4) nanopartiküllerin basit, hızlı ve etkili bir sentez tekniği olan mikrodalga destekli yakma metoduyla sentezlenebilirliği ve karakterizasyonu araştırılmıştır. Bu amaçla yakıt olarak üre kullanılarak CaAl2O4 nanopartiküller mikrodalga destekli yakma metoduyla sentezlenmiştir. Elde edilen ürünler TGA, XRD, FT-IR, SEM ve TEM teknikleri ile kapsamlı bir şekilde analiz edilmiştir. Bu üründe yapılan XRD ve FT-IR analizleri uygulanan mikrodalga etkisinin ürünlerin tam dönüşümünde tek başına yeterli olmadığı belirlenmiştir. Buna göre, elde edilen nanopartiküllerin yapısal ve morfolojik özelliklerini iyileştirmek ve ürüne dönüşüm oranını arttırmak için 300°C ile 1000°C derece arasında değişen sıcaklıklarda ısıl işleme tabi tutulmuştur. 800°C ve üzerindeki sıcaklıklarda uygulanan ısıl işlem sonrasında elde edilen partiküllerin tamamen kalsiyum aluminat nanopartiküllere dönüştükleri belirlenmiştir.

Bu çalışmada tel elektrot erozyon ile işlemede makine performansını değerlendirmede en önemli parametrelerden biri olan işleme hızı üzerine farklı tel elektrotların, soğutma yöntemlerinin ve iş parçalarının etkileri araştırılmıştır. Deneysel çalışmalarda, iş parçası malzemesi olarak AISI D2 takım çeliği ve AISI 304 paslanmaz çelik, tel elektrot olarak ise pirinç, bakır ve çinko kaplı pirinç tel elektrotlar ve soğutma tipi olarak püskürtmeli ve daldırılmış soğutma yöntemleri kullanılmıştır. İşleme hızı değerleri sonuçları farklı işleme parametrelerine bağlı olarak değerlendirilmiştir. Genel olarak elektrot tipine göre en yüksek kesme hızları bakır tel elektrot ile en düşük işleme hızları ise kaplamasız pirinç tel elektrot ile elde edilmiştir. Daldırılmış soğutma yöntemi En yüksek kesme hızları elde etmek açısından püskürtmeli yöntemden daha iyi sonuçlar vermiştir. Genellikle iş parçasına bağlı olarak en yüksek işleme hızları AISI D2 takım çeliği malzemesi işlenirken, en düşük işleme hızları ise AISI 304 östenitik paslanmaz çeliği işlenirken oluşmuştur.

The organic fraction of municipal waste, OFMW, management is one of the main concerns for urban waste managers in developed countries. Composting this biodegradable urban waste and using the compost in agricultural activities is a quickly growing method and is a viable option to manage urban waste in both the developed and the developing world. This research presents the example of the management proposal for Cartagena city in Spain, in which the technical and environment feasibility has been studied. This work aimed to evaluate the composting of a mixture of different residues, namely organic waste, pruning, and Posidonia oceanica (L.) Delile, which was collected from the beaches of the municipality while cleaning. Mixtures 1, M1 (composed of 20% OFMW and 40% pruning and seaweed) and 3, M3 (composed of 30% OFMW and 70% pruning) proved to be the best to reach the ideal compost (1.23-0.08-1.28 NPK and 2.22-0.33-3.45 NPK, respectively). An extreme mixture, M2, was evaluated (50% PO; 50% pruning) but poor results were obtained due to a non-optimal initial C/N by not containing OFMW. At the same time, the volumes by urban nucleus and the viability of different composting strategies have been studied, proposing that 180,000 inhabitants use the centralized composting plant and almost 31,000 inhabitants use self-composting and community composting. Considering the carbon footprint of this management, the value was 50% lower than the total management in a centralized plant. Moreover, the final use of compost is optimum with self-composting and community composting because it is nearest to agricultural consumptions, also reducing the transport of the final product.

Indirect bridge health monitoring is conducted by running an instrumented vehicle over a bridge, where the vehicle serves as a source of excitation and as a signal receiver; however, it is also important to investigate the response of the instrumented vehicle while it is in a stationary position while the bridge is excited by other source of excitation. In this paper, a numerical model of a stationary vehicle parked on a bridge excited by another moving vehicle is developed. Both stationary and moving vehicles are modeled as spring–mass single-degree-of-freedom systems. The bridges are simply supported and are modeled as 1D beam elements. It is known that the stationary vehicle response is different from the true bridge response at the same location. This paper investigates the effectiveness of contact-point response in reflecting the true response of the bridge. The stationary vehicle response is obtained from the numerical model, and its contact-point response is calculated by MATLAB. The contact-point response of the stationary vehicle is investigated under various conditions. These conditions include different vehicle frequencies, damped and undamped conditions, different locations of the stationary vehicle, road roughness effects, different moving vehicle speeds and masses, and a longer span for the bridge. In the time domain, the discrepancy of the stationary vehicle response with the true bridge response is clear, while the contact-point response agrees well with the true bridge response. The contact-point response could detect the first, second, and third modes of frequency clearly, unlike the stationary vehicle response spectra.

دراسة أثر إضافة الغضار المكلسن والكلس على خواص المتانة للتربة الغضارية الإنتفاخية إبراهيم حمود عارف السويداني أيمن المذيب بدايةً تم الحصول على الغضار المكلسن بتعريض عينات من التربة الغضارية موضوع الدراسة، إلى مستويات مختلفة من درجات الحرارة هي على الترتيب °C 450, 650, 850 لمدة ثلاث ساعات في فرن مخبري، وتم اختبار الفعالية البوزولانية (الرابطة) لعينات التربة الغضارية المعالجة عند كل مستوى حرارة باستخدام اختبار شابيل المعدل test modified) (Chapelle، وهو الشق الكيميائي لاختبار الفعالية البوزولانية، وللتأكيد على الفعالية البوزولانية تم اختبار المقاومة للكسر لعينات مكعبية (4×4×4cm) محضرة من الغضار المكلسن والكلس والرمل القياسي، حيث أشارت النتائج إلى تطور مقاومة العينات للكسر مع زيادة درجة حرارة المعالجة للغضار المكلسن وزمن الإنضاج للعينات. تمّ تحضير تركيبات مزجية من التربة الغضارية والكلس والغضار المكلسن الذي تمّ الحصول عليه من نفس التربة، وفق أفضل نتيجة لاختبار الفعالية البوزولانية، ومن أجل عزل تأثير الغضار المكلسن، تمّ تثبيت نسبة إضافة الكلس عند القيمة (%6) من الكتلة الجافة للتربة، بينما أضيف الغضار المكلسن بنسب تتراوح بين (0 ،10% و%20)، وأجريت اختبارات رص التربة بقالب بروكتور النظامي ، خواص القوام (حدود اتربرغ)، الضغط غير المحصور وفق محور واحد (UCS)، نسبة تحمل كاليفورنيا (CBR) ، وذلك عند كل نسبة مزجية ولكل اختبار من الاختبارات السابقة، حيث تم استخلاص الرطوبة المثالية والكثافة الجافة العظمى عند كل نسبة مزجية، وقد أظهرت النتائج تحسناً متزايداً في خواص القوام مع انخفاض قرينة اللدونة بتزايد نسبة الإضافة من الغضار المكلسن إلى التربة المحسنة بالكلس، أما الضغط غير المحصور وفق محور واحد (UCS) فقد ارتفعت قيمته من (315KPa) إلى(569 KPa) عند النسبة المزجية 6% كلس- %20غضار مكلسن، في حين كان التحسن الأكثر وضوحاً هو في قيم نسبة تحمل كاليفورنيا (CBR) التي ارتفعت من (2.89%) إلى (79.41%) عند النسبة المزجية ذاتها، وهي أفضل نتيجة تم الحصول عليها، في دلالة واضحة على تحسن المتانة الذي طرأ على التربة الغضارية المعالجة بالغضار المكلسن والكلس. Calcined clay was obtained by thermal treatment of the clayey soil used in this study, with three levels of temperature ranges from (450, 650, 850°C) for 3hours in a laboratory furnace. Pozzolanic activities of treated soil samples, were determined using Chapelle test modified at each level, and the third level(850°C/3hours) was chosen as it was the best result of Chapelle test. To emphasis the pozzolanic activity, another test was carried out by using cubic specimens (4x4x4cm) in compressive strength measurements of mortars containing calcined clay, lime and standard sand, the results showed appreciable development in strength with the increase of temperature range and curing time of specimens. Combinations of clayey soil, lime and calcined clay according to the best result obtained from Chapelle test, were prepared, lime was added by constant percentage (6%) of dry weight of soil in all combinations, while the calcined clay ranged from (0%) to (20%). The testes that carried out on each combination were: compression test in standard proctor mould, Atterberg limits, Unconfined Compressive Strength (UCS), California Bearing Ratio (CBR). The optimum moisture content and maximum dry density were obtained, and the results showed improvement in consistency properties with the decrease in plasticity index by the increase of percentages of calcined clay added to the clayey soil stabilized by lime, unconfined compressive strength increased from (315 KPa) to (569 KPa), the most obviously parameter increasing was (CBR) which increased from (2.89%) to(79.41%), all of that at the combination 6% lime, 20% calcined clay. that was a clear indicator to the improvement that took place in the clayey soil strength properties, when treated with calcined clay and lime.

Acute appendicitis it a quite common abdominal disorder and considered as a difficult diagnosis. An accurate diagnosis is essential to prevent any complication from delayed surgical intervention. Aim: To evaluate the diagnostic accuracy of ultrasound in acute appendicitis cases in Saudi Arabia compared with histopathology. Moreover, to determine whether there is a correlation between the accuracy of ultrasound in acute appendicitis and the sonographers’ expertise. Methods: A retrospective study was conducted, including patients who admitted to the emergency room with clinical symptoms of suspected acute appendicitis and underwent ultrasound examinations. Diagnostic features, including diameter of the appendix ≥7 mm, free fluid, lack of compressibility, no appendix seen, normal appearance, and thick wall, were recorded for each patient. Results: Only 61 of the 132 patients in the study were accurately diagnosed with the use of ultrasound. Just 44 of them were diagnosed with appendicitis (true positives) and 17 without appendicitis (true negatives). However, 69 patients who had positive histopathologic results received a negative ultrasound diagnosis (false negatives), and 2 patients with negative histopathologic findings had a positive ultrasound diagnosis (false positives). There was no significant association between the accuracy of the ultrasound diagnosis and the years of experience of the sonographers. Conclusion: a low level of diagnostic accuracy was demonstrated when utilizing ultrasound to diagnose cases of acute appendicitis. In addition, no association was found between the years of experience of the sonographer conducting the examination and the diagnosis of acute appendicitis.

Smoking is well known to be correlated with cardiovascular abnormalities, in particular atherosclerosis and heart diseases. This article investigates the effect and relationship of smoking tobacco on the thickness of the intima–media (IMT) belonging to the common carotid arteries (CCAs), and also blood concentration of the lipid profile (LP), mainly the total cholesterol, High Density Lipoprotein (HDL), Low Density Lipoprotein (LDL) and also triglycerides. Nineteen male tobacco smokers and thirty-five healthy male non-smoking Saudi participants were involved in this study after obtaining their informed consent. An ultrasound and a spectrophotometer were used to determine the IMTs and lipid parameters, respectively. The thicknesses of the smokers’ right (RCA) and left carotid (LCA) arteries (0.72 and 0.7 mm, respectively) were significantly greater than the thicknesses of the arteries of the non-smokers (0.58 and 0.62 mm, respectively) (p-value = 0.005 and 0.04). Insignificant differences between the means of the other parameters in the two groups were studied. Smoking is a risk factor for stroke, because it significantly increases the IMTs of both the right and left carotid arteries.

Pleurotus ostreatus that known as poplar, beech and oyster mushrooms is second generation after Agaricus bisporus with the fungal species. Fresh and processed mushrooms products are in great demand worldwide in terms of taste and flavor. Edible mushrooms produced in the world is consumed fresh 40-50%. However, due to the high moisture content and enzyme, harvested mushrooms that can be stored for about one week and shows rapid loss of quality in the storage process. This situation limits the consumption of fresh edible fungus, so the marketing of canned mushrooms, drying and freezing and storage technology has come to the fore. In this study, besides the drying, unlike other studies it is intended to optimize the pulverization of the fungus accordingto the food processing operation. As a result of optimization, drying conditions of 50 °C and 269.02 minutes was concluded as the most suitable drying standard. EC50 value, Total Phenolic Content and desirability rate are determinated respectively; 275.464, 0.762 and 0.976 in this norm.

Ülkemizde kavak, kayın ve istiridye mantarı olarak bilinen Pleurotus ostreatus, Agaricus bisporus’dan (şapkalı mantar) sonra üretimi yapılan ikinci mantar türüdür. Taze ve işlenmiş mantarlar ürünleri dünya çapında tat ve lezzetleri bakımından büyük ilgi görmektedir. Dünyada üretilen yemeklik mantarın %40-50’si taze olarak tüketilmektedir. Ancak hasat edilen mantar yüksek nem ve enzim içeriği nedeniyle ancak ortalama bir hafta depolanabilmekte ve depolama sürecinde hızla kalite kaybı görülmektedir. Yapılan bu çalışmada diğer çalışmalardan farklı olarak mantarın kurutulmasının yanında gıda işleme prosesine uygun olarak toz haline getirilmesinin optimize edilmesi amaçlanmıştır. Yapılan optimizasyon sonucunda 50 °C’de 269.02 dk. yapılan kurutma işleminin en uygun kurutma normu olduğu sonucuna varılmıştır. Bu sıcaklık ve süre normlarında bulunan EC50 değeri, Toplam Fenolik Madde Miktarı ve istenebilirlik oranı sırası ile; 275.464, 0.762 ve 0.976 olarak belirlenmiştir.

Ülkemizde kavak, kayın ve istiridye mantarı olarak bilinen Pleurotus ostreatus, Agaricus bisporus’dan (şapkalı mantar) sonra üretimi yapılan ikinci mantar türüdür. Taze ve işlenmiş mantarlar ürünleri dünya çapında tat ve lezzetleri bakımından büyük ilgi görmektedir. Dünyada üretilen yemeklik mantarın %40-50’si taze olarak tüketilmektedir. Ancak hasat edilen mantar yüksek nem ve enzim içeriği nedeniyle ancak ortalama bir hafta depolanabilmekte ve depolama sürecinde hızla kalite kaybı görülmektedir. Yapılan bu çalışmada diğer çalışmalardan farklı olarak mantarın kurutulmasının yanında gıda işleme prosesine uygun olarak toz haline getirilmesinin optimize edilmesi amaçlanmıştır. Yapılan optimizasyon sonucunda 50 °C’de 269.02 dk. yapılan kurutma işleminin en uygun kurutma normu olduğu sonucuna varılmıştır. Bu sıcaklık ve süre normlarında bulunan EC50 değeri, Toplam Fenolik Madde Miktarı ve istenebilirlik oranı sırası ile; 275.464, 0.762 ve 0.976 olarak belirlenmiştir.

Ülkemizde kavak, kayın ve istiridye mantarı olarak bilinen Pleurotus ostreatus, Agaricus bisporus’dan (şapkalı mantar) sonra üretimi yapılan ikinci mantar türüdür. Taze ve işlenmiş mantarlar ürünleri dünya çapında tat ve lezzetleri bakımından büyük ilgi görmektedir. Dünyada üretilen yemeklik mantarın %40-50’si taze olarak tüketilmektedir. Ancak hasat edilen mantar yüksek nem ve enzim içeriği nedeniyle ancak ortalama bir hafta depolanabilmekte ve depolama sürecinde hızla kalite kaybı görülmektedir. Yapılan bu çalışmada diğer çalışmalardan farklı olarak mantarın kurutulmasının yanında gıda işleme prosesine uygun olarak toz haline getirilmesinin optimize edilmesi amaçlanmıştır. Yapılan optimizasyon sonucunda 50 °C’de 269.02 dk. yapılan kurutma işleminin en uygun kurutma normu olduğu sonucuna varılmıştır. Bu sıcaklık ve süre normlarında bulunan EC50 değeri, Toplam Fenolik Madde Miktarı ve istenebilirlik oranı sırası ile; 275.464, 0.762 ve 0.976 olarak belirlenmiştir.

This study employed stable isotopes of δ18O and δ2H in conjunction with other hydrological parameters to understand the origin, inferred residence time, and seasonal effect of groundwater in the shallow aquifers of the eastern Dahomey Basin. A total of 230 groundwater samples (97 in the wet season and 133 in the dry season) were collected from the borehole and shallow aquifer between May 2017 and April 2018. Groundwater analysis included major ions and δ18O and δ2H, isotopes data in precipitation from three selected Global Network of Isotope in Precipitation (GNIP) stations across West Africa, Douala in Cameroon, Cotonou in Republic of Benin, and Kano in Nigeria were used in comparative analysis. Results of the hydrochemical model revealed Ca-HCO3 and Na-Cl as dominant water types with other mixing water types such as Ca–SO4, Ca–Cl, Na–SO4, and K–Mg–HCO3, which characterised early stage of groundwater transformation as it infiltrates through vadose zone into the aquifer. δ18O and δ2H precipitation data from the three stations plotted along with the groundwater samples indicate recent meteoric water origin, with little effect of evaporation during the dry season. The plot of Total Dissolved Solids (TDS) against δ18O showed clustering of the water samples between the recharge and the evaporation zone with dry season samples trending towards increased TDS, which is an indication of the subtle effect of evaporation during this period. Tracing groundwater types along the flow paths within the basin is problematic and attributed to the heterogeneity of the aquifer with anthropogenic influences. Moreover, a comparison of the δ18O and δ2H isotopic compositions of groundwater and precipitation in the three selected stations, with their respective deuterium excess (D-excess) values established low evapotranspiration induced isotope enrichment, which could be due to higher precipitation and humidity in the region resulting in low isotope fractionation; hence, little effect of seasonal variations. The study, therefore, suggested groundwater recharge in the shallow aquifer in the eastern Dahomey Basin is of meteoric origin with a short residence time of water flows from soils through the vadose zone to the aquifers.

Meeting long-term rural community water supply needs requires diligent geohydrological conceptualisation. Study of Malawi’s Lake Chilwa Basin, including sampling of 330 water points in Phalombe District, enabled assessment of groundwater quality influence upon supply. The control of larger Lake Chilwa paleo-environments on current Basin groundwater quality is demonstrated. Lacustrine sediment deposition forming high-level deposits under open lake conditions and terrace deposits under open and closed lake conditions significantly control the groundwater major-ion quality and salinity now observed. Paleo-lake extent marks the transition between low-TDS (total dissolved solids) groundwater suitable for water supply at higher elevations and high-TDS brackish groundwater in areas overlain by lacustrine deposits closer to the current lake level. Low-TDS groundwater is limited to mid-to-low reach influent leakage of rivers incising terraces. Permeable fluvial deposits within the deeper paleo-river channel may possibly provide low-TDS water. The conceptual model, whereby paleo-lake controls groundwater salinity, provides science-based evidence to address policy to manage the significant water point functionality concerns quantified at the district and river basin scales. Targeting of the low-TDS groundwater alongside improved use of upland low-TDS stream/river sources with fewer, but larger capacity, and better maintained gravity-fed supply schemes are recommended. This study hence shows the value of paleo-geohydrology interpretation of the lake–groundwater system conceptualisation to inform Sustainable Development Goal 6 (SDG 6.5.1)—integrated water resources management policy for rural water supply.

The objective of this study was to evaluate the surface quality of experimentally manufactured wood plastic composite (WPC) samples exposed to water soaking. Eastern redcedar (Juniperus virginiana L.), which is one of the invasive species in Oklahoma, USA, and recycled plastic were used to manufacture WPC samples. Three types of samples, namely with 0%, 3% and 6% nano-clay were soaked in water for up to one month. Stylus-type equipment was employed to evaluate their surface roughness as a function of water exposure. Two accepted roughness parameters, average roughness (Ra) and mean peak-to-valley (Rz), were used to determine changes in the surface quality of the specimens due to water exposure. Average roughness values of 1.5 µm and 4.1 µm were determined for the samples with no clay in dry conditions and those soaked for one month in water, respectively. Corresponding values were lower in the case of those with clay in their content. Based on the findings in this work, it appears that the stylus technique can be successfully applied to such samples to quantitatively evaluate their surface quality when they are exposed to water for an extended time span. It is expected that data from this work could help to produce a better understanding of the behavior of WPCs under environmental conditions.

Pleurotus ostreatus that known as poplar, beech and oyster mushrooms is second generation after Agaricus bisporus with the fungal species. Fresh and processed mushrooms products are in great demand worldwide in terms of taste and flavor. Edible mushrooms produced in the world is consumed fresh 40-50%. However, due to the high moisture content and enzyme, harvested mushrooms that can be stored for about one week and shows rapid loss of quality in the storage process. This situation limits the consumption of fresh edible fungus, so the marketing of canned mushrooms, drying and freezing and storage technology has come to the fore. In this study, besides the drying, unlike other studies it is intended to optimize the pulverization of the fungus accordingto the food processing operation. As a result of optimization, drying conditions of 50 °C and 269.02 minutes was concluded as the most suitable drying standard. EC50 value, Total Phenolic Content and desirability rate are determinated respectively; 275.464, 0.762 and 0.976 in this norm.

This paper aimed at developing advanced Logit discrete choice models with several individual and mode attributes affecting the prediction of individual choice. The models have been applied to Port-Said (PS) city and have been used to investigate innovative transport systems such as Bus Rapid Transit (BRT) as a hypothetical mode situation beside the regular modes of transport (car and taxi). The methodology provides data collection of PS transportation mode system and develops Multinomial Logit Model (MNL), Nested Logit Model (NL), and Mixed Logit Model (MXL) using Visual-tm Software. The survey was formed by the Stated Preference (SP) technique conducted for individuals from all PS zones and the predictable travel mode choice behavior was analyzed. The findings showed that in PS, income is the most important attribute affecting the mode choice behavior model. The high values and positive signs of income parameters indicate that the higher income earners are more likely to use private car than taxi or bus. Contrary to most cases in developed countries, out-of-vehicle time that represents the accessibility shows higher impacts than the in-vehicle time as a result of poor access facilities in developing countries.

The destination choice is an essential step of the travel demand modeling. Many previous studies were concentrated onland use which means that the utilization of land for different activities such as residential, commercial, industrial,educational, etc. is linked with travel demand. Accessibility is often seen to be an important determinant of the activitiesdestination choice. This study is concerned with using the accessibility concept to investigate the utility function of theactivity destination choice. A case study is Port Said (PS) City in Egypt. The characteristics of time, cost, and incomelevel are obtained from activity based comprehensive transportation surveys. The benefit or utility of choosing aspecific activity (BM values) are estimated based on the calculation of accessibility benefit from time-space geographymeasures for different zones in PS. Binary and Multinomial logit models were used for daily activities performed byindividuals. During different time segment, the model predicts individual probability of choosing one of the followingfive activities: work, shopping, school, university, and Leisure. The accessibility benefits are examined associating withdecreasing travel time (public transport-oriented development), improving income level for poor, and restricting car use.Finally, the model approved to be sensitive to different measures and hence it can be used as an effective informativetool to the decision makers.

Traffic turning movement counts at roundabouts is one of the key inputs required for roundabout assessment, control and management. Traditionally, a direct counting is conducted to track a vehicle from entering through circulation until exiting. This counting may be difficult and costly due to the size of roundabout, the vision obstacles, and the continuous traffic flow. Many researchers tried to avoid the tracking problem by counting only at entries and exits, then estimating the movements based on historical data which unfortunately affect the results. Other researchers reduced the tracking problem by counting some turning movements in addition to at entries and exits, then calculating mathematically the remaining movements. This approach is practical and accurate; however, it was applied on limited cases. In this paper, a generalized mathematical model was developed to calculate the most difficult movements based on the easiest movements determined based on the size of monitoring area. The developed model can be used to calculate the turning movements, including the u-turns, for roundabouts with any number of legs. The developed model was presented in O–D matrix forms to be practical and user-friendly. The model was validated against reference count data and the results were found to be satisfactory.

The purpose of this pilot study was to evaluate the relationship between the kinematic variables of the right hand and left leg with ball velocity during jump-throwing phases in handball for better-informed training. We investigated ball velocity and the key kinematic variables of jump throwing during different throwing phases in three strides. Ten right-handed male handball professional players who had competed in the Egyptian Handball Super League participated in this study. Jump throwing performance was divided into three phases (cocking, acceleration and follow-through), which included eight events during the throwing. Five trials were captured for each player, and a 3D analysis was performed on the best trial. Results indicated that the velocity of the throwing hand was the most important variable during jump throwing, which was correlated with ball velocity during the three phases of performance in four events: Initial contact (IC) (r = 0.66*), initial flight (IF) (r = 63*), maximum height of the throwing hand (Max-HH) (r = 0.78*) and ground contact (GC) (r = 0.83*). In addition, the initial flight was the most important event in which players need to be using the best angles during performance, particularly the shoulder angle.

This paper presents an empirical evaluation of the relationship between operational performance and platooning phenomenon in rural two-lane roads in Egypt. Seven performance measures and three platooning variables were defined and calculated for eight study sites using traffic data from roads in Minoufiya governorate, Egypt. Using graphical and statistical analyses, the associations between the performance measures and the platooning variables were examined. The results showed that the follower density performance measure was found to have the strongest correlations to platooning variables. Among the platooning variables investigated, traffic flow in the direction of travel has the highest correlations with performance measures. The study demonstrated that the relationship between follower density and traffic flow is better described by a quadratic form. Finally, threshold values for different levels-of-service were proposed. This might help traffic engineers, in Egypt, to evaluate operational performance using criteria that reflect the local conditions of the area under study.

There are needs on electricity but people cannot get electricity including when doing outdoor activities at isolated areas, selling goods in night market and during disaster such as flood and earthquake. People need electricity especially for charging communication gadgets and lighting. Thus, the objective of this study is to develope and test the performance of a small prototype of thermoelectric generator (TEG) based power generation system. The TEG based power generation system developed consists of heat collector, thermoelectric generator, heat pipe and fin based heat sink, and DC-DC converter. The heat collector was designed to ensure the suitable temperature for the TEG which is should not exceed 320°C on the hot side. Heat pipes was used to increase the power output by lowering or maintaining the temperature at cold side, to ensure large temperature difference is obtained. The prototype was tested and data of temperature, voltage and current were collected. A cell phone was used during the test as a load to the system. All the data were recorded by using temperature data recorder, power meter and multimeter. It was found that the highest maximum power output was 7.7 watt at the temperature difference of 138°C. The output is sufficient to charge the cell phone and it is also possible to light an LED bulb. However, it did not achieve the maximum output of 43 W. This is a results of limitation of maximum electrical load (only one cell phone was used) and the limitation of the performance of the prototype. Thus, although the prototype is succesfully generate enough power to charge a cell phone, but improvement in heat sink design, and adding more electrical load are needed to get better results.

Heat sink lack of design is one reason that negatively affects the performance of thermoelectric modules. As compared to conventional cooling systems equipped with thermoelectric generators (TEG), heat pipe heat sink has various points of interest. Heat pipe heat sink is the most appropriate heat exchanger for medium temperature range under 300 °C. This paper demonstrates the effect of different materials of heat pipe-heat sink on the TEG performance. Two types of heat sinks were tested with TEG, one made from copper while the other from aluminium. The aim is to improve power output of TEG by an appropriate material of fins and metal block with heat pipes. The prototype was experimentally tested and the TEG cold side temperature, voltage and current were measured in both conditions, natural and forced convection. It was found that highest power output was achieved using copper heat sink in the case of forced convection, being 7.7 W whereas, lowest power output was obtained using aluminium heat sink in the case of natural convection, being 2.67 W. It is evident that copper heat sink is more effective than aluminium heat sink in terms of power output. However, both types of heat sink needs optimisation in terms of power output, cost and economic efficiency, while the results shown in this paper are just in terms of power output.

Numerous air conditioners are running without a proper refrigerant charge due to leakage and improper charging during installation. Therefore, there is a need to understand the performance of the air conditioner if it is not properly charged for the means of optimal operation and cost saving. This study is focusing on the usage of a used small capacity split-unit type air conditioner using R-22 refrigerant. The objective is to study the condenser performance over a variation of refrigerant charges. From the results, it is clear that the optimum refrigerant charge is 100%. The highest cooling capacity and COP were 3,330 J/s and 3.05 respectively.

In this paper, we propose model predictive control method for linear complementarity and extended linear complementarity systems by formulating optimization along prediction horizon as mixed integer quadratic program. Such systems contain interaction between continuous dynamics and discrete event systems, and therefore, can be categorized as hybrid systems. As linear complementarity and extended linear complementarity systems finds applications in different research areas, such as impact mechanical systems, traffic control and process control, this work will contribute to the development of control design method for those areas as well, as shown by three given examples.

Bu çalışmada, biyometrik yöntemlerden olan parmak izi tanıma sistemi için parmak izi görüntüsünden öznitelik noktaları elde edilmiştir. Bu öznitelik noktalar, parmak izi görüntüsünün özel donanımlarla sayısallaştırılması ve bu sayısal görüntünün bilgisayarda, bazı işlemler sonucu ortaya çıkarıldığı uç ve çatal noktalardır. Kişiye özgü bu parmak izi noktaların, akıllı kartla nasıl ilişkilendirildiği araştırıldı. Çeşitli akıllı kart okuyucu ve yazıcılarla, veri okuma ve yazma işlemleri gerçekleştirildi. Parmak izli akıllı kart geliştirme kitli cihazlar kullanılarak da biyometrik parmak izi bilgileri ve kimlik bilgileri akıllı kartlara başarıyla yazılarak kimliklendirme işlemi yapıldı. Burada biyometrik yöntemlerden parmak izi ve kart çeşitlerinden akıllı kartı tercih sebepleri de ortaya konulmuştur

During the last years, the authors are trying to integrate biometrics, inside a smart card. In this study the first step, as in every biometric system is to obtain an image of the user's fingerprint. After this, a preprocessing algorithm is applied, which enables feature extraction to obtain the location and type of all minutiae. The minutiae are ridges and valleys of the fingerprint. We researched these minutiae which are used with smart cards. A lot of smart card readers /writers were used for data writing and reading. Fingerprint minutiae and identify information were wrote on smart cards successfully using development kits (smart cards of fingerprint) and so were identified.

Bu çalışmada, biyometrik yöntemlerden olan parmak izi tanıma sistemi için parmak izi görüntüsünden öznitelik noktaları elde edilmiştir. Bu öznitelik noktalar, parmak izi görüntüsünün özel donanımlarla sayısallaştırılması ve bu sayısal görüntünün bilgisayarda, bazı işlemler sonucu ortaya çıkarıldığı uç ve çatal noktalardır. Kişiye özgü bu parmak izi noktaların, akıllı kartla nasıl ilişkilendirildiği araştırıldı. Çeşitli akıllı kart okuyucu ve yazıcılarla, veri okuma ve yazma işlemleri gerçekleştirildi. Parmak izli akıllı kart geliştirme kitli cihazlar kullanılarak da biyometrik parmak izi bilgileri ve kimlik bilgileri akıllı kartlara başarıyla yazılarak kimliklendirme işlemi yapıldı. Burada biyometrik yöntemlerden parmak izi ve kart çeşitlerinden akıllı kartı tercih sebepleri de ortaya konulmuştur

Bu çalışmada, biyometrik yöntemlerden olan parmak izi tanıma sistemi için parmak izi görüntüsünden öznitelik noktaları elde edilmiştir. Bu öznitelik noktalar, parmak izi görüntüsünün özel donanımlarla sayısallaştırılması ve bu sayısal görüntünün bilgisayarda, bazı işlemler sonucu ortaya çıkarıldığı uç ve çatal noktalardır. Kişiye özgü bu parmak izi noktaların, akıllı kartla nasıl ilişkilendirildiği araştırıldı. Çeşitli akıllı kart okuyucu ve yazıcılarla, veri okuma ve yazma işlemleri gerçekleştirildi. Parmak izli akıllı kart geliştirme kitli cihazlar kullanılarak da biyometrik parmak izi bilgileri ve kimlik bilgileri akıllı kartlara başarıyla yazılarak kimliklendirme işlemi yapıldı. Burada biyometrik yöntemlerden parmak izi ve kart çeşitlerinden akıllı kartı tercih sebepleri de ortaya konulmuştur

Bu çalışmada, biyometrik yöntemlerden olan parmak izi tanıma sistemi için parmak izi görüntüsünden öznitelik noktaları elde edilmiştir. Bu öznitelik noktalar, parmak izi görüntüsünün özel donanımlarla sayısallaştırılması ve bu sayısal görüntünün bilgisayarda, bazı işlemler sonucu ortaya çıkarıldığı uç ve çatal noktalardır. Kişiye özgü bu parmak izi noktaların, akıllı kartla nasıl ilişkilendirildiği araştırıldı. Çeşitli akıllı kart okuyucu ve yazıcılarla, veri okuma ve yazma işlemleri gerçekleştirildi. Parmak izli akıllı kart geliştirme kitli cihazlar kullanılarak da biyometrik parmak izi bilgileri ve kimlik bilgileri akıllı kartlara başarıyla yazılarak kimliklendirme işlemi yapıldı. Burada biyometrik yöntemlerden parmak izi ve kart çeşitlerinden akıllı kartı tercih sebepleri de ortaya konulmuştur

A significant problem in thermo-electric generators is the thermal design of the heat sink because it affects the performance of thermo-electric modules. As compared to conventional cooling systems, heat pipe heat sink have numerous advantages. Some of these advantages are: high heat-transfer rates; absence of moving parts and lack of auxiliary consumption (passive system). This paper presents the analysis of power generation using the combination of heat pipes and thermo-electric generators. The aim is to improve power output by an appropriate design of the heat sink. The average geometrical parameters of heat sink (fin height, fin space and fin thickness) were obtained from data collected from previous studies closely similar to this prototype. The prototype was tested and the temperature, voltage and current data were collected. All data were recorded by using a temperature data recorder, power meter and multimeter. It was found that the highest maximum power output was 1.925 watts at a temperature difference of 85°C. However, the prototype did not achieve the maximum output expected. This was a result of limitation of TEG model (where only one TEG was used) and the limitation of the performance of the prototype. The prototype successfully generated enough power to charge a cell phone and laptop when connected to two or three TEGs. Moreover the heat pipe heat sink needs optimization to meet the design output from the manufacturer of the TEG at hot side temperature and cold side temperature

Photovoltaic Thermal (PV/T) system emerged as one of the convenient type of renewable energy system acquire the ability to generate power and thermal energy in the absence of moving parts. However, the power output of PV/T is intermittent due to dependency on solar irradiation condition. Furthermore, its efficiency decreases because of cells instability at high temperature. On the other hand, fuel cell co-generation system (CGS) is another technology that can generate power and heat simultaneously. Integration of PV/T and fuel cell CGS could enhance the reliability and sustainability of both systems as well as increasing the overall system performance. Hence, this paper intended to present the parameters that affect performance of PV/T and Proton Exchange Membrane Fuel Cell (PEMFC) CGS. Moreover, recent developments on PV/T-fuel cell hybrid system are also presented. Based on literates, mass flow rate of moving fluid in PV/T was found to affect the system efficiency. For the PEMFC, when the heat is utilized, the system performance can be increased where the heat efficiency is similar to electrical efficiency which is about 50%. Recent developments of hybrid PV/T and fuel cell show that most of the studies only focus on the power generation of the system. There are less study on the both power and heat utilization which is indeed necessary in future development in term of operation strategy, optimization of size, and operation algorithm.