Cooperative Techniques for Next Generation HF Communication Systems

The high frequency (HF) band lies within 2-30 MHz of the electromagnetic spectrum. For decades, the HF band has been recognized as the primary means of long-range wireless communications. When satellite communication first emerged in 1960s, HF technology was considered to be obsolete. However, with its enduring qualities, HF communication survived through this competition and positioned itself as a powerful complementary and/or alternative technology to satellite communications. HF systems have been traditionally associated with low-rate data transmission. With the shift from analog to digital in voice communication, and increasing demands for high-rate data transmission (e.g., e-mail, Internet, FTP), HF communication has been going through a renaissance. Innovative techniques are required to push the capacity limits of the HF band. In this dissertation, we consider cooperative communication as an enabling technology to meet the challenging expectations of future generation HF communication systems. Cooperative communication exploits the broadcast nature of wireless transmission and relies on the cooperation of users relaying the information to one another. We address the design, analysis, and optimization of cooperative HF communication systems considering both multi-carrier and single-carrier architectures. As the multi-carrier HF system, we consider the combination of the orthogonal frequency division multiplexing (OFDM) with the bit interleaved coded modulation (BICM) as the underlying physical layer platform. It is assumed that cooperating nodes may use different HF propagation mechanisms, such as near-vertical-incidence sky wave (NVIS) and surface wave, to relay their received signals to the destination in different environmental scenarios. Diversity gain analysis, optimum relay selection strategy and power allocation between the source and relays are investigated for the proposed cooperative HF system. For single-carrier HF systems, we first derive a matched-filer-bound (MFB) on the error rate performance of the non-regenerative cooperative systems. The results from the MFB analysis are also used for relay selection and power allocation in the multi-relay cooperative systems. To overcome the intersymbol interference impairment induced by frequency-selectivity of the HF channel, equalization is inevitable at the destination in a single-carrier system. In this work, we investigate the minimum-mean-square-error (MMSE) based linear/decision-feedback frequency domain equalizers (FDEs). Both symbol-spaced and fractionally-spaced implementations of the proposed FDEs are considered and their performance is compared under different channel conditions and sampling phase errors at the relay and destination nodes.1 yea

Developing a Non-Cooperative Optimization Model for Water and Crop Area Allocation Based on Leader-Follower Game

In this paper, a mathematical model for conflict resolution among a diverse set of agricultural water users in Golestan province, Iran, is developed. Given the bi-level nature of the distribution of power in the current problem, a combination of Leader–Follower game and Nash–Harsanyi bargaining solution method is employed to find optimal water and crop area allocations. The Golestan Regional Water Authority is the leader in this setting, controlling the total water allocations; and the agricultural sectors are the followers, competing over the allocated water. Two objectives for the leader are (i) maximizing profits, and (ii) maximizing share of green water in total agricultural production through selecting more efficient crop patterns. The followers’ objective is merely maximizing obtained benefits for the selected crop patterns. Virtual water concept is also factored into the related objective functions, and the water allocation problem is solved considering spatio-temporal crop pattern along with a dynamic water pricing system. This involves using a hybrid optimization structure as a new approach to solving two level optimization problems. The results show that the leader’s income is independent of total water allocation and is only affected by crop pattern and crop area, two factors which drive water price too. The followers’ benefit also depends on crop pattern and crop area, as they influence the crop yield, cost and water price. Finally, green water plays a key role in selecting the optimal crop pattern and crop area

A Game Theory Approach for Conjunctive Use Optimization Model Based on Virtual Water Concept

In this study to allocate the agricultural and environmental water, considering virtual water concept, a multi-objective optimization model based on NSGA-II is developed. The objectives consist of equity maximization, agricultural benefit maximization for each region, maximization of green water utilization and finally minimization of environmental shortage. Then a cooperative game (Grand Coalition) model is presented by forming all possible coalitions. By the game model including Nucleolus, Proportional Nucleolus, Normal Nucleolus and Shapley methods, the benefit is reallocated based on all Pareto optimal solutions obtained from multi-objective optimization model. Then using two famous fallback bargaining methods, Unanimity and q-Approval, preferable alternative (solution) for each of the cooperative games is determined. Finally, based on the obtained benefit for each selected alternatives, the two most beneficial alternatives are chosen. The proposed methodology applied for water allocation of Minoo-Dasht, Azad-Shahr and Gonbad-Kavoos cities in Golestan province, Iran for a 3-year period as a case study. Also, eight crops including Wheat, Alfalfa, Barley, Bean, Rice, Corn, Soya, and Cotton are selected based on local experts’ recommendations. The models’ results indicated no significant difference between the grand coalition model and the multi-objective optimization model in terms of the average cultivation area (a relative change of 2.1%), while lower agricultural water allocation occurred for the grand coalition model (about 10.35 percent average) compared with the multi-objective optimization model. It is also observed that more agricultural benefit gained by the grand coalition model (32 percent average). Finally, it is found that Wheat and Corn hold the most rates of import and export, respectively, and Rice was the crop which has the least shortage of production to supply food demand

Nano silver-coated polypropylene water filter: I. manufacture by electron beam gun using a modified Balzers 760 machine

As adequate freshwater supplies decrease steadily, novel technologies are required for water purification. Nanotechnology, a new scientific frontier, promises to revolutionize innovation in many industries. Advancements in nanotechnology are being applied in the water-purification industry to keep harmful bacteria out of drinking water. Due to its bactericidal properties, nano silver is used in many products as an antibacterial. This study aimed to produce a nano silver-coated water-treatment polypropylene filter via the physical vapor deposition method using the Balzers 760 machine equipped with an electron beam gun ESQ 110. The Balzers machine was modified in order to enable coating of the cylindrical filters in a homogenous manner. The nano silver particles were made by electron beam bombardment of the silver metal, which were subsequently deposited on the polypropylene filter evenly. The thickness of the nano layer coated on the filter was about 55.0nm in average, as revealed by the microprocessor unit of the Balzers machine during the coating process. The thickness of the nano layer and the chemical composition of the produced filters were studied by scanning electron microscopy, atomic force microscopy and the X-ray diffraction technique. The filter system produced in this work has the potential to be used as an efficient and cost-effective water treatment method. The inductively coupled plasma/mass spectrometry (ICP/MS) studies revealed that there was no nano silver particle present in the filtered water sample. Hence, there is no risk of contamination of drinking water with the silver nano particles upon application of the manufactured filters. This is the first report on the manufacture of nano silver-coated cylindrical polypropylene filter using the electron beam gun technique

Complete removal of pathogenic bacteria from drinking water using nano silver-coated cylindrical polypropylene filters.

An attempt was made to investigate the removal of Escherichia coli bacteria from drinking water using nano silver-coated polypropylene water filter. For the production of nano silver filters, a modified Balzers 760 machine equipped with an electron beam gun was used. The nano-silver particles were made by electron beam bombardment of the silver metal, which were subsequently deposited on the polypropylene filters evenly. The thickness of the nano layer coated on the filters was 35.0 nm. The nano silver-coated filters were characterized using scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and atomic force microscopy. The antibacterial efficiency of the filters was evaluated using the membrane filter method. At a flow rate of 3 l/h, the output count of E. coli was zero after 7 h filtration when the input water had a bacterial load of 103 colony-forming units (cfu) per milliliter. The inductively coupled plasma/mass spectrometry (ICP/MS) results showed that the 35 nm layer of the silver nanoparticles were stable on the water filter and were not washed away by water flow even after 72 h

CN2F: A Cloud-Native Cellular Network Framework

Upcoming 5G and Beyond 5G (B5G) cellular networks aim to improve the efficiency and flexibility of mobile networks by incorporating various technologies, such as Software Defined Networking (SDN), Network Function Virtualization (NFV), and Network Slicing (NS). In this paper, we share our findings, accompanied by a comprehensive online codebase, about the best practice of using different open-source projects in order to realize a flexible testbed for academia and industrial Research and Development (R&D) activities on the future generation of cellular networks. In particular, a Cloud-Native Cellular Network Framework (CN2F) is presented which uses OpenAirInterface's codebase to generate cellular Virtual Network Functions (VNFs) and deploys Kubernetes to disperse and manage them among some worker nodes. Moreover, CN2F leverages ONOS and Mininet to emulate the effect of the IP transport networks in the fronthaul and backhaul of real cellular networks. In this paper, we also showcase two use cases of CN2F to demonstrate the importance of Edge Computing (EC) and the capability of Radio Access Network (RAN) slicing

Intratesticular versus intraperitoneal injection of Busulfan for the induction of azoospermia in a rat model

Abstract Background Administration of antineoplastic drugs may cause azoospermia driving to subfertility. Production of animal azoospermia models is essential for evaluating new treatment methods before therapeutic interventions in human setup. This study aimed to investigate the toxic effects of Busulfan (an anticancer drug) on some vital organs and describe the best method and appropriate dose of Busulfan to induce an animal azoospermia model. Methods Rats were randomly assigned into four groups, treatment groups received 10 mg/kg, 40 mg/kg Busulfan intraperitoneally (IP), 5 mg/kg Busulfan intratesticular (IT), and control group. Blood, bone marrow, liver, renal, and testes samples were collected for histological (H&E staining), biochemical (serum levels of ALT, AST, ALP, creatinine, and urea), and hematological analyses. Results Results revealed severe anemia and leukopenia in rats that received Busulfan via IP. By contrast, injection of 5 mg/kg Busulfan via IT did not cause anemia except with a mild decrease in RBC count. Non-significant differences in the M/E ratio were observed in all groups. The administration of 40 mg/kg of Busulfan led to evacuation and destruction in the spermatogenesis process with thin-walled seminiferous epithelium in most tubules, but in rats treated with 10 mg/kg of Busulfan, the normal spermatogenesis process was notified. IT injection of Busulfan contributed to the complete degradation of spermatogenesis in which all spermatogenic cells degenerated. In the renal tissue, hyperemia, extensive tubular necrosis degeneration, and hyaline casts were found after IP injection of Busulfan. In hepatic tissue, focal hemorrhagic, chronic cholangitis, and hepatocyte degeneration, and swelling were noticed. Biochemical analysis revealed apparent Busulfan toxicity of both hepatic and renal tissues in IP Busulfan-treated rats. Conclusions In summary, we found that the intratesticular injection of low doses of Busulfan (5 mg/kg) is a relatively non-invasive and safe method for producing the rat azoospermia model causing the least toxicity on vital organs

Relationships between Oxidative Stress, Liver, and Erythrocyte Injury, Trace Elements and Parasite Burden in Sheep Naturally Infected with Dicrocoelium dendriticum

Background: The aim of this study was to investigate the role of oxidative stress in the pathology of ovine dicrocoeliasis. Methods: During Dec 2013 - Oct 2014, seventy-two sheep (1-3 years) with liver dicrocoeliasis along with 47 healthy sheep were selected from animals admitted for slaughtering at slaughterhouse located in Neyshabour, Razavi Khorasan Province, Iran. Results: In comparison to healthy control, the malondialdehyde (MDA) level and serum total antioxidant capacity were significantly higher in the parasitized group (P<0.05). A significant increase in liver MDA concentration (P<0.05) of parasitized group was also observed. Packed cell volume (PCV), zinc, iron, total bilirubin and albumin sera levels were significantly lower in the parasitized group (P<0.05). In parasitized sheep, a significant positive correlation was seen between serum MDA concentration and the activity of aspartate aminotransferase (AST). On the other hand, the concentration of serum MDA was inversely correlated with the value of PCV. No significant differences were observed for MDA concentration and total antioxidant capacity between normal and abnormal hepatic lobes in the parasitized animals. Oxidative stress markers (MDA and total antioxidant capacity in serum and liver samples) showed no significant correlations with the extent of pathological lesions and serum variables of liver injury in the parasitized sheep. No significant correlation was observed between oxidative stress markers and the fluke’s number in the parasitized animals. Conclusion: Oxidative stress may play an important role in the erythrocyte destruction in sheep naturally infected with D. dendriticum. However, no clear relationships were observed between the oxidative stress, hepatic damage and parasite burden

Wide-AdGraph: Detecting Ad Trackers with a Wide Dependency Chain Graph

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