This paper investigates the Multi-band OFDM (MBOFDM) based physical (PHY) layer proposal for IEEE 802.15.3a working group on short-range high data-rate Ultra-wide-Band (UWB) communications. An overview of the MB-OFDM PHY layer architecture with its various parameters is presented and the optimal choice of critical parameters is discussed. Next, we derive the theoretical un-coded Bit Error Rate (BER) of MB-OFDM over the Rayleigh fading channel. performance results over realistic IEEE UWB channel models are analyzed and compared to a pulsed-OFDM based approach. Although pulsed-OFDM was presented in the literature as an enhancement to the MB-OFDM approach, simulation results showed that with same redundancy-factor, both systems give almost similar BER performance.

Rapid increase in motor vehicles, especially cars, and over-use in urban areas, coupled with population growth and unrestrained expansion, as well as lack of scientific and comprehensive planning and the lack of an efficient public transport system., Causing problems such as severe environmental pollution, overwhelming traffic congestion, wasting citizens' time, excessive energy consumption, road insecurity and accidents, leading to injury and death, such as living in cities. Big has made it difficult. Therefore, the purpose of this study is to evaluate the performance of the BRT bus system in Karaj metropolis based on transport indexes. The method of collecting information in this research is library and field documents through questionnaire. At first, based on questionnaire information and interviews with experts in the field of transportation and urban management of Karaj and using Likert spectrum, effective criteria were used to evaluate the performance of fast bus system. Prioritization of the criteria was then performed using AHP. Data were analyzed by SPSS software. The results showed that out of the 23 criteria identified, ten are effective in bystander performance, the most important of which is crowding with weight (0. 2259). Among the criteria evaluated, time priority measures with weight (0. 222), travel time with weight (0. 184) were the next priority.

The present study deals with the energy analysis of a new design of the triple generation system of cooling, heating and solar power to supply energy for a hospital complex. The proposed system includes concentrator collectors of the linear Fresnel reflector type with a thermal photovoltaic absorber, which uses solar energy to generate electrical and thermal energy, respectively, for sale to the grid and providing part of the energy for cooling and heating cycles. The proposed cooling system in this structure is a single-effect lithium bromide-water absorption chiller. The gas-burner support heating structure is intended to meet a part of the energy needs of the cooling and heating system non-satisfied by the solar cycle. The system analysis under the thermal load of a hospital complex has been performed annually. The results show that 30% of the system's annual energy is supplied by the solar cycle. In addition, the proposed structure also generates 77.7 MWH of electrical energy. The studied system provides all its energy needs from solar energy on the hottest day from 9:00 to 15:00. The proposed collector has a better performance than the thermal photovoltaic collector without concentrator and the thermal concentrator collector.

The existence or absence of an effective performance evaluation system is directly related to the life or death of organizations. Organizations are supposed to work hard to optimize this system. This research is intended to review, analyze and criticize the performance evaluation system in an organization. This applied research follows a descriptive-survey method. The statistical population of this research contains managers who are involved in the design, implementation and monitoring of performance evaluation system. They include 30 experts working in Tehran province all of whom were selected as sample group. Six questionnaires were distributed among the subjects in six statistical stages. To investigate the challenges involved in performance evaluation system, the normal data from the Kolmogorov-Smirnov test was employed. Furthermore, the multivariable regression method was used to measure the impact of each of the identified problems on the employees’ evaluation system. The results indicated that the performance evaluation system is suffering from problems and shortcomings in all dimensions (inputs, content, evaluators, examinees, performance methods, and outcomes).

Purpose: The success or failure of governments is measured by the rational implementation of government management subsystems, especially performance evaluation. Evaluating health performance using national and international components is essential. Unfortunately, the current ranking of Iran's health in the international arena reflects the relative inefficiency of the government performance. Therefore, this study aimed to provide a model for evaluating government performance in the field of health and to develop applied knowledge in the field of organization. Over time, it should be extended to other areas of government responsibility, as well. Design/ methodology/ approach: The present qualitative study adopted the systematic approach of Strauss and Corbin and employed the "Grounded Theory" strategy. To collect the data, unstructured interviews were carried out with 19 academic-professional organizations experts. The data were analyzed according to the guidelines of open and axial coding. Research Findings: The results were conceptualized in the form of 87 sub-categories and classified under 6 main categories emphasizing the implementation of the performance evaluation model in accordance with the proposed efficient and effective components and indicators using the knowledge of local calligraphy experts and the use of international standards. Limitations & Consequences: The prevalence of Corona virus and lack of easy access to experts were among the limitations of this study. Practical Consequences: The successful implementation of the strategy is a function of the executive context under the heading of "strong evaluation and monitoring" as a causal condition of the event. "Efficient implementation," along with "comprehensive database" and "sustainable situation," leads to the final outcome which is "Optimized resources and expenditures", "achieving organizational effectiveness" and "increased government efficiency and productivity" and provides the basis for the realization of the welfare state. Innovation or value of the Article: In this research, the most important components and indicators of the evaluation of the government's performance in the field of health were identified and customized in the form of a proposed performance evaluation model, which is the initiative of this research. Paper Type: Research Article

The treatment of wastewater generated from acrylonitrile butadiene styrene (ABS) resin manufacturing industry have a great importance due to its high chemical oxygen demand (COD) and some other toxic substances. Activated carbon adsorption, chemical oxidation and biodegradation are the most conventional methods to the treatment of ABS effluents. Among them, the biological treatment as an environmentally friendly technology is highly regarded in the bio treatment and biotransformation of the toxic compounds of ABS wastewater to the intermediate and final compounds such as CO2 and water. This study was conducted to evaluate the performance of an activated sludge system for pretreating ABS manufacturing effluents. The wastewater pretreatment plant is consisted of 3 fine screens, a grit chamber, an equalization basin, dissolved air floatation (DAF) system, an activated sludge reactor and a final clarifier. This system was operated to reduce the TSS and COD values in the effluent in order to obtain to interior discharge permits to the central wastewater treatment utility operated by Tabriz petrochemical complex. Four runs weighed average sampling was conducted during 6 months according to the standard methods of the examination of water and wastewater. The parameters including COD, BOD5, TSS, TDS, sulfate, total kjeldahl nitrogen (TKN), ammonia-N, nitrate-N, alkalinity, cyanide, phosphate and pH were measured in wastewater samples according to the standard methods. The concentrations of acrylonitrile, acrylamide and acrylic acid in wastewater samples were determined using gas chromatography (GC) equipped with flame ionization detector (FID) with capillary column. Microbial structure of activated sludge was also evaluated using R2A, PCA and Nutrient Agar culture media as well the biochemical standard tests. According to the results, at surface loading rate of 2.76 m3/m2.h applied to DAF, the COD and TSS removal efficiencies of 24 and 43% were obtained, respectively. The ratio of BOD5/COD in the influent was 0.57 indicated the moderate biodegradability of ABS wastewater. In addition, the COD and BOD5 removal efficiencies in biological reactor were 59 and 68% respectively, at the organic loading rates (OLR) of 0.79±0.06 kgCOD/m3.d. Totally, the COD, BOD5 and TSS removal efficiencies in the pretreatment system were 80, 90 and 88%, respectively. In addition, at the acrylonitrile loading rates of 0.067±0.008 kg ACN/ m3.d, the removal efficiency of acrylonitrile was 91% which 26% of that has occurred in the biological reactor. Also, the removal efficiency of cyanide was 97% which only 4% of that has occurred in the biological reactor. Twenty bacterial strains were isolated and identified from the activated sludge samples. Among the isolated bacterial strains, four strains include Alcaligenes sp. Pseudomonas sp. Bacillus sp. and Moraxella sp. were identified as heterotrophic nitrifiers. Based on the results, the nitrifier bacteria have played an important role in the degradation of acrylonitrile in the biological activated sludge system. The results of parameters analysis, performance evaluation and microbial assessment revealed the satisfactory performance of COD removal as well nitrification. However, it seems that a significant portion of the volatile organic compounds (VOCs) are removed from the influent wastewater by stripping.

Direct discharge of high-strength industrial effluent often upsets municipal wastewater treatment plant processes. This pilot study was undertaken to evaluate the performance of a UASB system in pre-treating effluent from a medium-size traditional slaughterhouse. Experiments were conducted in a continuous flow 500-1 pilot plant initially inoculated with 2001 municipal anaerobic digested sludge. With an influent COD concentration of 3000-5000 mg/I. the system was started with a loading of 1.8 kg COD/m3.d (F/M of 0.24 kg COD/kg VSS.d) at 25°C. The granules formed after 4 months of operation were dark brownish with a diameter of 1-4 mm and a settling velocity of 20 m/hr. Once granules were formed, up flow velocity was gradually increased to 0.8-1 m/hr (HRT of 2.5 hr) and VSS concentration reached 25 g/I. It was possible to increase the loading up to 14 kg COD/m3.d (F/M of 1.4 kg COD/VSS.d) at 29°C with total COD removal efficiencies of 85-90%. Under these conditions 250-350 I gas (75% methane) was generated for each kg COD removed.

Hydrogen is usually used as a means of storing the energy produced from renewable energy resources. The electrolyzer, meanwhile, is a system by which hydrogen can be produced sustainably. In the present paper, a Concentrated Photovoltaic Thermal/Organic Rankine Cycle (CPVT/ORC) system coupled with a PEM electrolyzer system is simulated and evaluated. Concentrated solar radiation is used as the input energy of the coupled system. Part of this radiation is converted directly into electrical energy using the Photovoltaic (PV) panel, and the rest enters the organic Rankine cycle system as heat. The heat in the cycle is converted into mechanical power by the turbine and finally into electrical energy by the generator. The total electrical power generated by the organic Rankin panel and cycle enters the electrolyzer for producing hydrogen. A combination of MATLAB and REFPROP software was used to simulate the system performance. The most striking result is that that the net generating power of the system is equal to 3820 watts, which is equivalent to producing 0. 02072 grams per second of hydrogen and 0. 0829 grams per second of oxygen.