Arash Bayat

With the growth of urbanization and the increasing demand for cooling in high-rise buildings, energy consumption associated with cooling systems has become one of the major challenges in the building sector. Studies indicate that the use of mechanical cooling equipment accounts for a significant share of energy consumption and greenhouse gas emissions, a trend expected to accelerate by 2050. Therefore, adopting innovative strategies to reduce cooling loads—particularly the integration of passive cooling systems—appears to be a sustainable and cost-effective approach. Numerous studies have investigated passive cooling systems, including the enhancement of traditional systems and their integration with phase change materials (PCMs). In recent decades, PCMs have been recognized as one of the effective elements in building cooling. Beyond their direct application in architectural and structural components (such as walls), PCMs have demonstrated remarkable performance when combined with passive cooling systems. In this thesis, with a focus on residential and non-residential high-rise buildings, a passive cooling–based approach was designed and presented, aiming to reduce energy consumption while maintaining indoor thermal comfort. However, challenges such as excessive weight, occupation of usable building space, and the possibility of independent cooling for individual spaces are also critical, yet often overlooked in previous studies. Based on the literature review, the following research questions were formulated: 1.   How can the integration of passive cooling systems with phase change materials and forced airflow ensure thermal comfort for occupants in high-rise buildings? 2.   To what extent does the proposed system contribute to reducing cooling load and maintaining indoor comfort conditions? The research method was experimental, relying on field testing. In the first stage, following a review of previous studies and identification of knowledge gaps, a passive cooling system was designed and constructed with the objectives of reducing energy use, weight, and space occupation compared to conventional systems, while enabling independent thermal comfort control in each space. The experimental tests were conducted at the Faculty of Arts and Architecture, Razi University, Kermanshah. A controlled office room was considered as the outdoor environment, and a test chamber was built as the indoor space. The cooling system prototype, measuring 55 × 21.80 × 95 cm and weighing 19.45 kg (lighter than comparable systems), was installed inside the test chamber (122 × 106 × 170 cm). To evaluate the system’s performance, three experimental scenarios were tested on consecutive days. The first scenario (07/04/1404) employed an organic Bio-PCM with a melting point of 22–23 °C. The second and third scenarios (08/04/1404 and 09/04/1404) used mixtures of 60% organic Bio-PCM + 40% coconut oil (melting point 20–21 °C), and pure liquid paraffin (melting point 20 °C), respectively. The PCMs were embedded in 15 copper tubes, each 50 cm long. Data were recorded at one-hour intervals between 9:00 a.m. and 3:00 p.m. using a hot-wire anemometer, a dual-channel data logger, and temperature-humidity sensors.

Concrete, as the most widely used construction material, is constantly exposed to aggressive environmental factors that reduce its durability and mechanical performance. Among these factors, sulfate attack and calcium leaching are considered the most critical deterioration mechanisms, simultaneously inducing chemical and mechanical weaknesses in concrete. This research was conducted to evaluate the mechanical behavior and durability of concrete under the combined effect of magnesium sulfate and ammonium nitrate solutions. For this purpose, standard concrete specimens were exposed to the aggressive environment for two durations (0 and 30 days) and subsequently assessed through mechanical, physical, and microstructural tests. The mechanical tests revealed that compressive strength decreased by 37.7%, from 28.95 MPa to 18.04 MPa, within 30 days. Moreover, tensile strength and fracture parameters, including fracture energy and fracture toughness, exhibited significant reductions in both notch geometries (0.1 and 0.5), indicating increased brittleness of the cementitious matrix. Physical tests further showed longitudinal and volumetric expansions caused by the formation of expansive phases such as ettringite and gypsum, which accelerated deterioration through microcracking. In contrast, weight change was minimal, suggesting that the dominant processes were related to structural and chemical alterations rather than mass gain. Microstructural analyses using SEM and EDS confirmed a notable reduction in calcium content and a decline in the Ca/Si ratio in 30-day specimens. These findings indicated the weakening of the C–S–H phase and increased porosity, which were directly correlated with strength loss and higher brittleness. Overall, the results demonstrate that the combined sulfate–nitrate environment can cause severe deterioration of the mechanical properties and durability of concrete even within a short exposure period of one month. From a practical perspective, these outcomes highlight the necessity of employing low-permeability mix designs, pozzolanic materials, and protective coatings in similar structures. Furthermore, the experimental data can serve as a basis for developing standards and design strategies aimed at extending the service life and reducing the maintenance costs of concrete structures.

  Given the global energy crises and the importance

In the seismic design of steel structures, the use of efficient lateral load-bearing systems capable of dissipating energy and controlling displacements is of great importance. Steel shear walls are widely used, but the main challenge with thin plates is the phenomenon of out-of-plane buckling, which can occur before full yielding and reduce the system's load-bearing capacity. This research aims to evaluate the potential of using aluminum shear walls as a ductile alternative by numerically and parametrically investigating the seismic performance of steel frames strengthened with this system. The present study was conducted using the Finite Element Method in ABAQUS software. To ensure the accuracy of the modeling, a numerical model was first developed and validated against the results of a reputable experimental study on a steel shear wall, achieving a suitable agreement between the force-displacement curves. In the main phase of the research, a comprehensive parametric study was performed on a single-story, single-bay steel frame strengthened with an aluminum shear wall. The primary variables included the aluminum panel thickness (at three levels: 1, 2, and 3 mm) and the ratio of the wall width to the bay span (at ten levels from 0.1 to 1.0), forming a total of 30 models. All models were analyzed under quasi-static cyclic loading, and indicators such as strength, stiffness, and energy absorption were extracted. Finally, the effect of adding a cross-shaped stiffener to one of the models was also evaluated. The results showed that adding an aluminum shear wall significantly improves the seismic performance of the frame. In the optimal case (F-1-3), the ultimate strength increased by 2.41 times, the initial stiffness by 12.42 times, and the energy absorption capacity by 5.81 times compared to the bare frame. It was found that increasing both the thickness and width of the wall directly leads to the enhancement of all performance indicators and, by controlling buckling, shifts the structural behavior towards the formation of a uniform and stable diagonal tension field. Furthermore, the addition of a stiffener, with a 42% increase in ultimate strength, proved its effectiveness as a viable strategy for optimization and further increasing the system's load-bearing capacity.   

In this research, biological plasticizer   were made based on edible oil waste using epoxidation and esterification reactions. The purpose of this study is to evaluate the effects of adding these bioplasticizers in PVC as a plasticizer and compare its properties with dioctyl phthalate (petroleum-based plasticizer). In this evaluation, FTIR, TGA, DSC analyses, brittleness test during stretching, hardness testing, and migration and fugacity resistance testing were performed. By performing the TGA test, it was found that the PVC sample synthesized with our bioplasticizer has a higher degradation temperature, which means more heat resistance compared to other samples. The tensile test analysis showed that the PVC produced with bioplasticizer in Compared with dioctyl phthalate, it has good tensile stability and the failure graph during stretching was close to the graph of dioctyl phthalate, which results showed that it has almost the same behavior as dioctyl phthalate and this softener can improve the flexibility of PVC.Then, by examining the dissolution of different synthesized samples in different solvents (polar and non-polar), we came to the conclusion that the reduction in the mass of the sample synthesized with this biological softener in non-polar solvents was significantly less and more stable, but in Polar solvents were more reducing the mass of the sample due to the polar structure of the bioplasticizer. Also, compared to other samples, it showed lower volatility and higher thermal stability in the volatility test.

  Separation of gas-solid flows is an important process in many industries. Cyclone separators are the most common devices for separating solid particles from gas flows, which indicates the importance of studying and researching to increase their efficiency and reduce energy consumption by reducing the pressure drop. In this regard, the present study used an additional inlet to enter flow into the cyclone with the aim of increasing the separation efficiency of a standard gas cyclone. To find the optimal height, this additional inlet was added at four different heights along the length of the cyclone, including the heights of 0.95D, 1.4D, 1.5D and 1.95D (D is the diameter of cylindrical section of cyclone) and the results were obtained for two conditions of inlet flow distributions: Increasing the inlet flowrate and division the inlet flowrate. In the first case, in addition to the polluted air flow entered through the original inlet (that was equal to the flowrate of cyclone without an additional inlet), an extra flowrate (20% of flowrate of original inlet) was injected through the additional inlet. In other words, the total flowrate of the cyclone was 20% more than it in cyclone without additional inlet. In second case, part of the inlet flow (83.33%) was injected through the original inlet and part of it (16.67%) was injected through the additional inlet, so the total inlet flowrate was equal to it in cyclone without additional inlet. The Reynold stress turbulence model (RSM) was used to solve the Averaged Navier- Stokes equations and Eulerian- Lagrangian approach and discrete phase model (DPM) was applied to track particles with a uniform diameter of 0.5 to 1.8 micron as discrete phase. The results showed that, in both flow distribution cases, installing the additional inlet at a height of 0.95D has the most positive effect on the separation efficiency. The separation efficiency increased 28.8% in flowrate increasing case and 19.6% in flowrate division case for particles with diameter of 0.5 micron compared to cyclone without additional inlet. In addition, in both of the flow distribution cases, increasing the separation efficiency of sub-micron particles was greater than it of bigger particles.

  The present study was performed to evaluate the effect of Millard reaction on improving the antimicrobial properties of nisin against gram-positive and gram-negative bacteria. Nisin alone is able to fight most gram-positive bacteria, but this is not the case This is not the case with gram-negative resistant bacteria because of the resistant structure of the cell wall These are bacteria that do not allow nisin to penetrate. To achieve the optimum temperature for the nisin-xanthan reaction in three ratios of 1: 1, 1: 2 and 1: 4 At 110 minutes, according to the studied articles, 4 temperature variables of 60, 75, 90, 105 ° C were selected to examine the effect of the performance of each during fluorescence spectroscopy. The result of comparing different temperatures showed that up to 90 ° C we see good performance and then we experience a decrease in performance, so 90 ° C was introduced as the optimal temperature. To achieve the optimal time, the spectra obtained from fluorescence as well as conjugate nisin and xanthan at 30, 45, 90, 110 minutes and 3-4-5 hours and in three ratios of 1-1 1-2 1-4 were examined and Also, the spectra obtained from nisin heated and unseen fluorescence at temperatures of 30, 45, 90, 110 minutes and 3-4-5 hours and in three ratios of 1 2 4 were studied to achieve the optimal temperature. The result of the study of fluorescence peaks indicated that up to 110 minutes we see the highest peak or maximum intensity of the peak and then we face a decrease in fluorescence intensity, so 110 minutes was introduced as the optimal reaction time. The ratio of nisin in kangougite is effective as a result of the fluorescence spectrum, and the higher the ratio of nisin to xanthan, the higher or higher the fluorescence intensity, and this is in perfect agreement with the results of antibacterial activity. 1-4 was declared as the optimal ratio. Observing the peak diagram around 420-440 in the spectra, we conclude that fluorescence is associated with the first stage of the Millard reaction and the development of fluorescent compounds formed in the reaction as precursors of brown pigments. Examination of the peaks obtained from spectroscopy of conjugate nisin and xanthan at times 30, 45, 90, 110 minutes and 3-4-5 hours and in three ratios 1-1 1-2 1-4 were examined by observing the peak of about 280-290 nm, which is related to the formation of the shift base, and confirms the formation of conjugate, and with increasing heating time in all three ratios 1-1 1-2 1-4 increase Has found. Examination of FT-IR peaks also indicates the formation of a conjugate and the formation of a conjugate, resulting in a Millard reaction. To express the result of bacterial contamination, it can be pointed out that the results of discoloration in each plate well after the addition of MTT are consistent with the table of bacterial contamination and the results of Alizarider. That each The more colorful the color inside each well in the image, the larger the results Absorption was reported higher in the ELISA reader as well as in contamination measurements Wells have been reported to have more colonies by bacteria. By examining the presence or absence of a colony in each well, comparing it with the numbers reported in Alizairder, we obtained the concentration required to inhibit or kill bacteria.

Abstract Economic dispatch is one of the most important problems in operation of power systems. The purpose of the economic dispatch problems is to obtain the generation power units in a way that supplies the demanded loads (including electrical and thermal powers) and meet different constraints at minimum cost. On the other hand, with increasing pollutants and environmental pollution, concerns have been raised. For this reason, the economic emission dispatch problems, which are considered in both sides, are very important today. On the other hand, due to the failure of classical and mathematical methods, to solve these problems, considering the various restrictions of power system, due to the existence of local minimums, nonlinear, non-convex, and non-smooth of the problem, the use of evolutionary optimization methods has been increased. Therefore, in this thesis, ICA algorithm, hybridizing TVAC-PSO with EMA algorithm, and a new method based on fast non-dominated sorting and dynamic crowding distance are used to solve problems of CHPED, CEED, and also solving multi-objectives problems of CHPEED and DEED. In each case, each one is applied on several test systems and their results are compared with those obtained from other known methods, the results of which show the effectiveness and superiority of the proposed methods over other methods, in each of these fields. In addition, the statistical comparison results of the proposed new method prove its robustness and reliability. Also, a constraint handling technique, for the first time in the field, is integrated into the proposed hybrid algorithm, and its effectiveness in satisfying constraints at least cost compared to other methods is shown in constrained CEED problem. Finally, in order to evaluate the proposed hybrid algorithm in solving practical problems, a new dynamic multi-objective test system is introduced and solved by considering system practical constraints, such as ramp rate limit, prohibited operating zones, valve point loading effect, spinning reserve, transmission electrical losses and multi-fuel.Satisfaction of all of these constraints indicates the appropriateness of the procedure used in this algorithm. o Keywords: Economic Dispatch, Transmission Electrical Losses, Multi-fuel, Spinning Reserve, Valve Point Loading Effect, Prohibited Operating Zones, Constraint Handling, Dynamic Economic Emission Dispatch  

  با آغاز روند نوسازي معاصر بسياري از ساختارها و بافت­هاي شهر ايراني اسلامي دچار دگرگوني شدند. از اين رو بسياري از عناصر مهم و تاريخي شهري كه معادني از پيشينه و شخصيت شهر را در خود داشت به مرور از ميان رفت و شهرها شكل وساختار تازه و ناهمگوني به خود گرفتند.شهر تاريخي كرمانشاه كه بر سر راه تجاري ايران و عراق قرار دارد؛ با پيشينه تاريخي درخور در دوران مختلف از اهميت چشمگيري برخوردار بود و بنا بر اسناد تاريخي تا اواخر دوره­ي قاجار در اوج رونق و شكوفايي بوده است. از اين رو در دوران تاريخي كرمانشاه، از مركز شهري پويا و با عناصر گوناگوني يرخوردار بود. پس از آن با فرآيند نوسازي اين شهر نيز، چون بسياري از شهرهاي ايران، تحولات عميقي را تجربه كرد و به­تبع مركز شهر دچار دگرگوني ژرفي شد. علاوه بر آن معماري شهر دوران گذشته، با همنشيني عناصر تاريخي، فرهنگي، مذهبي و تجاري درمركز شهر، به نوعي پيوستگي ميان اين مكان­ها برقرار كرده و به بافت شهر انسجام مي­بخشيد.  مسئله اي كه امروز در رابطه با اين دگرگوني­ها حائز اهميت است عدم توجه و انسجام بخشي به اماكن تاريخي و فرهنگي و ارائه ساختاري نمايان و روشن از شهر كرمانشاه است. شهر امروز با تمام پتانسل هاي موجود در آن در زمينه معماري و بافت هاي جاذب از جهت پرداختن به اين جاذبه ها كه مي­تواند به نوعي به بهبود وضعيت شهري، فرهنگي، اجتماعي واقتصادي كمك نمايد مورد بي مهري قرار گرفته است.   متاسفانه، علي­رغم وجود عناصر فرهنگي در نقاط مختلف شهر، هنوز هم خلاء وجود اين مكان­ها در مركز شهر كه مهم­ترين قسمت شهر محسوب شده و بيشترين حضور مردم در آن صورت مي­پذيرد، به­شدت احساس مي­شود.پژوهش حاضر در نظر دارد با تحليل و بررسي يكي از عناصر تاريخي واقع در مركز شهر (تكيه معاون­الملك)، وشناخت ويژگي­هاي بافت مركزي شهر (محله فيض آباد)، همچنين با بررسي اسناد و مدارك كتابخانه­اي و تجارب به­دست­آمده از بررسي نمونه­هاي موردي، فرآيند پيشنهادي براي بازآفريني اين نقطه از شهر از طريق طراحي بنايي فرهنگي صورت دهد.        كلمات كليدي: كرمانشاه، مراكزشهري ، عناصر تاريخي و فرهنگي ، بازآفريني