Coverage improvement is one of the main problems in wireless sensor networks. Given a finite number of sensors, improvement of the sensor deployment will provide sufficient sensor Coverage and save cost of sensors for locating in grid points. For achieving good Coverage, the sensors should be placed in adequate places. This paper uses the genetic and learning automata as intelligent methods for solving the blanket sensor placement. In this paper an NP-complete problem for arbitrary sensor fields is described which is one of the most important issues in the research fields, so the proposed algorithm is going to solve this problem by considering two factors: first, the complete Coverage and second, the minimum used sensors. The proposed method is examined in different areas using MATLAB. The results confirm the successes of using this new method in sensor placement; also they show that the new method is more efficient than other methods like FAPBIL and MDPSO in large areas

Wireless sensor networks have been widely considered as one of the most important 21th century technologies and are used in so many applications such as environmental monitoring, security and surveillance. Wireless sensor networks are used when it is not possible or convenient to supply signaling or power supply wires to a wireless sensor node. The wireless sensor node must be battery powered. Coverage and network lifetime are major problems in WSNs so in order to address this difficulty we propose a combinational method consists of fuzzy-logic and genetic algorithms. The proposed scheme detects the Coverage holes in the network and selects the most appropriate hole’ s neighbor to move towards the blank area and compensate the Coverage loss with fuzzy-logic contribution and above node new coordinate is determined by genetic algorithm. As fuzzy-logic will be so effective if more than one factor influence on decision making and also genetic algorithms perform well in dynamic problems so our proposed solution results in fast, optimized and reliable output.

The Internet of Things (IoT) is an important part of realizing the smart city and the network Coverage of IoT plays a crucial role in this regard. Various parameters such as bandwidth, transmission power, noise and environmental conditions are effective in IoT network Coverage. The LoRaWAN is one of the main low-power long-distance protocols for the IoT communication. Implementing the infrastructure, providing IT solutions based on LoRa technology, and securing communication infrastructure are among the capabilities offered in this area. The purpose of this article is to describe the parameters needed to improve performance and increase LoRaWAN Coverage. Accordingly, different bandwidth and broadcast factor parameters are tested in the noisy environment and the noise impact on the Coverage and bit rate are achieved. Finally, a parameter-based application is implemented and a low-cost, high-Coverage, and fixed data rate method is discussed and simulated to make a parking lot intelligent in Tehran.

In this paper, we present a bi-objective virtual-force local search particle swarm optimization (BVFPSO) algorithm to improve the placement of sensors in wireless sensor networks while it simultaneously increases the Coverage rate and preserves the battery energy of the sensors. Mostly, sensor nodes in a wireless sensor network are first randomly deployed in the target area, and their deployment should be then modified such that some objective functions are obtained. In the proposed BVFPSO algorithm, PSO is used as the basic meta-heuristic algorithm and the virtual-force operator is used as the local search. As far as we know, this is the first time that a bi-objective PSO algorithm has been combined with a virtual force operator to improve the Coverage rate of sensors while preserving their battery energy. The results of the simulations on some initial random deployments with the different numbers of sensors show that the BVFPSO algorithm by combining two objectives and using virtual-force local search is enabled to achieve a more efficient deployment in comparison to the competitive algorithms PSO, GA, FRED and VFA with providing simultaneously maximum Coverage rate and the minimum energy consumption.

Background and Aims: Metal-free and fiber-reinforced composite (FRC) restorations have drawn considerable attention and interest in recent years for restoring in the posterior area due to their improved esthetics. Fracture resistance is one of the most important mechanical properties of materials because of 500-600 N load of occlusion. The restorations should tolerate this load. The purpose of this in vitro study was to compare the fracture resistance of FRC with that of zirconia all-ceramic for posterior partial dentures.Materials and Methods: Forty extracted human intact teeth (20 first premolars and 20 first molars) selected for fabricating 10 pairs of fiber-reinforced composite and 10 pairs of zirconia all-ceramic bridges. After receiving standard tooth preparation, the teeth were mounted with 7.5 mm distance between each other. The bridges were made and cemented on the teeth. Then the restorations were stored in 37oC water for 30 days. The fracture resistance was measured using mechanical testing machine with cross-head speed of 1mm/min. Data were evaluated by Independent sample t test.Results: The mean fracture resistance in the ceramic group was 1329.41 N and for the F.R.C group was 1118.528 N with significant differences between them (P=0.034). The failure modes were mainly cohesive at pontic area for ceramic samples, but adhesive for FRC samples at pontic area.Conclusion: Both systems showed sufficient fracture resistance for using in posterior area.

Sensor placement is a critical issue in wireless sensor networks that affects the quality of wireless sensor network Coverage. In this paper, we propose an improved virtual force algorithm based on the states of matter (IVFASM) for relocating sensors of a mobile wireless sensor network. IVFASM simulates the behavior of molecules in different states of matter to improve the Coverage of sensors. In the proposed IVASM algorithm, the strength of repulsive forces, the kinetic energy of the matter molecules, and attraction radius are dynamically adjusted over time according to different states of matter. As a result, in the gaseous state, sensors move rapidly apart; in the liquid state, sensors absorb each other to fill small holes gradually; in the solid state, sensors stabilize their final position. In the simulation, different states of matter led to improved Coverage and fewer holes. Evaluation of the proposed method on 14 sample problems with the different numbers of sensors and comparison of the results with state of the art revealed that the proposed method can achieve a higher Coverage rate in almost all sample problems. For a sample problem of 30 sensors, genetic algorithm (GA) and particle swarm optimization (PSO) achieved a Coverage ratio of 69%, fuzzy redeployment algorithm (FRED) achieved a Coverage ratio of 72%, classical virtual force algorithm (VFA) obtained a Coverage ratio of 79%, improved virtual force algorithm based on area intensity (IVFAI) achieved a Coverage ratio of 82%, and our proposed method IVFASM achieved a Coverage ratio of 83%.

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More than 22% of the world's agricultural land is saline, and this trend continues to increase with climate changes. Salinity stress causes leaf color change, osmotic stress, ionic toxicity, prevents growth, photosynthesis and plant performance. Due to their size less than micron, metal nanoparticles have a great absorption and transmission power in plants. Salinity stress is a major problem in hot and dry areas under tomato cultivation. For this purpose, investigating the mutual effects of the size and type of zinc oxide and iron oxide nanoparticles on the improvement and change of growth and increasing the resistance to salt stress in tomato plants of the early urbana variety were carried out in the form of a completely randomized and factorial design with 4 replications, at a significant level of 5%. In this research, zinc oxide nanoparticles in 25 and 50 nm sizes, iron oxide in 25 nm sizes and sodium chloride in 0 and 75 mM levels were used. Nanoparticles and salinity treatments were both applied to the plants. The results showed that salt stress led to a decrease in plant growth parameters such as shoot and root length, leaf area, RWC, ion leakage. Also, NaCl led to an increase in the accumulation of prolin and other aldehydes, sodium, iron and zinc. The application of nanoparticles had a slight effect in stress-free conditions, but in stressed conditions, these two nanoparticles alone and especially in combination neutralized the effect of salinity and reduced the damage caused by salinity stress.

A B S T R A C TThe present study was conducted to investigate the factors affecting improving the quality of urban housing. This research is applied in terms of purpose and in terms of descriptive-analytical method. The statistical population of the research was the residents of 8 residential complexes of Atabak neighborhood in District 15 of Tehran. Based on Cochran's formula, 384 questionnaires were distributed among residents. Finally, 380 complete and error-free questionnaires were collected. The data collection tool was a questionnaire, the validity of which was verified in the form of face and face validity, as well as divergent validity and reliability of the questionnaire using Cronbach's alpha and composite reliability. Analysis of data and information was done using SPSS and PLS software. The findings of this research showed physical quality with a path coefficient of 0.368, the variable of access to urban services with a path coefficient of 0.339, the variable of housing social conditions with a path coefficient of 0.169, and environmental quality with a path coefficient of 0.302 has a positive and significant impact on housing quality. According to the path coefficient obtained for the research variables, the amount of their impact on housing quality is evaluated as average. Among the identified factors, the factor of physical quality with a path coefficient of 0.368 has the most significant impact, and the factor of access to urban services with a path coefficient of 0.339 is ranked second. Also, this factor has a positive and significant effect on the physical quality factor of housing.Extended AbstractIntroductionAtabak neighborhood is one of the neighborhoods of District 15 of Tehran. In this neighborhood, physical changes have been made according to the interventions of the Tehran municipality in line with the implementation of the urban landscape plan and organized (inflow of private sector capital) in different years so far. Along with these interventions, the inadequacy of infrastructure and services to meet the population's needs has become this neighborhood's basic problem. Attention to its qualitative aspect needs to be addressed. This matter is important from the point of view of providing the city's basic needs, equitable distribution of facilities and resources, reducing urban inequalities, improving economic-social indicators, preventing unbridled and unplanned expansion, and ultimately improving the quality of life of the people. It demands that the quality of housing and the factors affecting it be evaluated and that a double effort be made to improve it, and it can provide a suitable context for providing suitable models of housing quality for citizens. Considering the mentioned cases, this research aims to answer the question:- What are the effective factors in improving the quality of housing? MethodologyThe current research is descriptive-analytical. In terms of purpose, it is in the category of applied research. Two library and field methods have collected the information needed for this research. In the field method, primary data collection has been done according to the research questions by designing a 5-scale Likert scale questionnaire. The statistical population of the study was the residents of Mobaat, Minabi, Atabek, Shahrak Sajjadieh, Yas, Zahid Gilani, Shahid Asadi, and Safa residential complexes located in Atabak neighborhood of District 15 of Tehran. The statistical population was equal to 20469 people, and based on Cochran's formula, 384 questionnaires were distributed among residents. Finally, 380 complete and error-free questionnaires were collected; the validity of the questionnaire was confirmed in the form of face and face validity as well as divergent validity. In order to check the reliability of the questionnaire, Cronbach's alpha and combined reliability were used, and according to the results presented in the research findings section, the reliability of the questionnaire was confirmed. The data obtained from this research were analyzed using structural modeling using SPSS and PLS software. Results and discussion This research showed that physical quality has a positive and significant effect on improving housing quality; according to the value of the obtained path coefficient, which is equal to 0.368, the value of this effect is considered moderate. Based on the results, it can be said that physical dimensions, such as the physical crystallization of housing, are the most objective and material issues in housing evaluation, analysis, and planning. Concerning the impact of access to urban services on the quality of housing, the findings indicated a significant impact of access to urban services. In explaining the results of this section, it can be said that gradually, the housing is changing from a single purpose to a shelter. Those other aspects of welfare and social comfort are also added; the limits of enjoying services and access to the essentials of life are shown to evaluate the housing quality. These indicators are very important in determining housing quality and are an integral part of housing planning. Access to urban housing services is considered one of the main indicators of life, which the Population Crisis Committee has used to measure quality in the world's metropolises. In relation to social conditions and environmental quality on the quality of housing, the results of this research confirmed the impact of the social environment and environmental quality on the quality of housing. Creating residential spaces is a topic that has been discussed previously. From the beginning, human beings have tried to create a favorable living environment that matches the quality conditions of their residence's social and environmental environment. ConclusionThis research was written to explain the factors affecting improving the quality of urban housing. The findings of this research showed that among the studied factors, the physical quality factor with a path coefficient of 0.368 has the most significant impact on improving the quality of urban housing in Tehran, such that this factor can explain 13.5% of the variance of the housing quality condition variable. Physical quality is defined based on the structural basis of a building and is often defined in the form of rules and standards related to it. The physical quality is sometimes interpreted as the appearance of buildings. Since they are fixed and real things, they are the reason for the emergence of general indicators for housing evaluation. The second factor is access to urban services with a path coefficient of 0.339, so this factor can explain 11.4% of the variance of the housing quality condition variable. This factor has been ranked second regarding the impact on housing quality according to the path coefficient value obtained. In third place was the factor of environmental quality with the path coefficient value of 0.302, and this factor can explain 1.9% of the variance of the variable of housing quality. Moreover, in the last place is the factor of housing social conditions, which has a path coefficient of 0.196. Also, from the other results of this research, we can mention the positive effect of access to the quality of urban services on the improvement of the physical condition of housing, and the value of the path coefficient obtained for this effect is equal to 0.623 so that it is 38.8% of the variance of the variable. FundingThere is no funding support. Authors’ ContributionThe authors contributed equally to the conceptualization and writing of the article. All of the authors approthe contenttent of the manuscript and agreed on all aspects of the work declaration of competing interest none. Conflict of InterestThe authors declared no conflict of interest. Acknowledgments We are grateful to all the scientific consultants of this paper.