This paper presents the design of a wideband 2-6 GHz phased array transmitter using Rotman lens. This transmitter can be used as a Radar system transmitter. The design is implemented and analysed using SystemVue simulation tool, where different components of the transmitter are designed according to required specifications.
Phase-locked loops (PLLs) are widely used in the synchronization of grid connected single-phase power electronic-based equipments due to their ease of digital implementation and satisfactory response. Generally in PLLs, the estimated frequency undergoes a large transient when a phase angle jump occurs. To resolve this problem, a frequency-locked loop (FLL) is proposed. In the proposed approach, frequency and phase estimation algorithms are developed such that the phase estimation loop is external to the frequency estimation loop, therefore, contrary to PLLs, the proposed FLL minimizes the coupling that exists between frequency and phase. This reduces the large transient experienced in the estimated frequency when a phase angle jump occurs. Simulation result is presented to demonstrate the effectiveness of the proposed approach.
Recent researches in cognitive visual analysis of crowd have indicated that crowd modeling is conventionally based on density analysis. However, socio-cognitive behavior studies have demonstrated that crowds often display a wide variety of behaviors that arise spontaneously from the collective motions of unconnected individuals. Therefore, behavior analysis employing physics-based approaches only, thereby neglecting the socio-psychological aspects, may present diverse challenges to accurate inference. This means that by identifying and modeling some of the interacting agents that underpin the evolution of such behaviors, we can deliver contexts that can help in the autonomous analysis of social and antisocial behaviors in crowded environments. This paper discusses these issues from the machine vision perspective. In particular, socio-cognitive models of crowds are linked to low-level mechanisms of crowd modeling and features extraction. A survey of recent works on crowd behavior analysis is conducted under a proposed behavioral categorization based on the level of the performed analysis and identified behaviors.
Business Process (BP) is a set of activities performed to achieve specific organizational goals. The discipline that governs BPs is called Business Process Management (BPM), it includes different method for the modeling, executing and monitoring BPs. Typically, Business Rules (BR) are used to enforce regulations and policies on the BP. In this paper, we discuss a simple language for the generation of BR directly from BPMN models based on a fragment of First-Order Logic (FOL). The rules are based on control-flow aspects of the BPMN that is divided into a set of components. To automate the language, A JAVA-based tool to generate the FOL rules is implemented.
Fast search engines are required for real-time decision making in various fields including computer vision, machine learning and object recognition. In the case of Internet of things (IoT) devices that need to implement fast search engines, it is of paramount importance to keep both area and energy costs at minimal. Conventional CMOS-based search engines suffer from density and power limitations. In this paper, we propose a reconfigurable memristor-based XNOR CAM cell (VR-CAM) that can support Binary-CAM (BCAM), Ternary-CAM (TCAM) and Approximate search. The proposed cell accepts the input search data as voltage and the database as memristor value (resistor). Whereas the output result in the form of voltage for TCAM and BCAM and resistance for approximate search. Based on this cell, a memristor-based CAM architecture is proposed. The architecture is composed of multiple banks of specially connected memristors for each bit. Simulations of the proposed architecture for search functionalities were carried out using LTSpice circuit simulator. The proposed CAM architectures achieves a 1-ns search cycle time. It utilizes 2 memristor devices per cell with option for stateful output.
This paper addresses the connectivity issues in urban Vehicular Ad-Hoc Network (VANET) using the cluster-based QoS-OLSR protocol. VANET in urban suffers from frequent topology changes and disconnections due to several urban characteristics such as intersections, obstacles and traffic lights. Therefore, network connectivity is an important metric for routing in urban. The proposed protocol is an extension of the existing cluster-based QoS-OLSR which connects only 2-hop away heads through an MPR. The enhanced protocol connects 2-hop away heads as well as 3-hop away heads which increase the network connectivity. The proposed protocol outperformed the existing protocol in terms of packet delivery ratio and end-to-end delay.
In this paper, a technique that explores a new scheme that is suitable for the available hardware requirements when modeling and linearizing the power amplifier (PA) with wide-band signals is proposed. The aim of the proposed technique is to relax the sampling rate requirements of the analog-to-digital convertors (ADC) in the digital pre-distortion (DPD) systems. The proposed resampling approach is based on under-sampling the output of the PA that results in a low-rate ADC, and efficiently restoring the under-sampled signal for DPD model extraction. The validity of the method is evaluated using a 20-MHz LTE input signal, and it shows excellent potential in restoring the full-rate signal from the under-sampled.
For space missions, the flight heritage of components is crucial, and it is a key element for mission success. One of the major components is the (FS) Flight Software, which is considered as an essential part of mission success. Hence, the same concept is applicable of the flight software since it is verified, and been tested in space. The FS process needs to be well defined in order to contain all the requirements, and avoid delays in the project. In this paper, we proposed a methodology for developing the flight software for nano-satellite systems. MYSAT-1 mission has been used as a case study for the proposed methodology.
This paper aimed at investigating the thermal performance of Double Skin Fa?ade (DSF) for an existing conventional residential building located in Irbid, Jordan. Special focuses were implemented on the different geometry shapes of the DSF to achieve the maximum benefits possible in attaining the thermal comfort zones with the minimum usage of the fossil-fuels based machinery. Simulation through the IES VE software confirmed that both the cavity width and geometry of the DSF have a massive impact in obtaining a relatively moderate thermal zone during winter seasons and an acceptable indoor temperature during summer seasons. All scenarios showed a significant improvement of the building's thermal performance in comparison to the base case, where this research focuses on selecting the most appropriate DSF's geometry in order to achieve the highest possible energy reduction.
Cities today, owing to the rapid urbanization and population increase, are grappling with several urban issues such as pollution, congestion, personal health, and safety. Sustainable development through new planning approaches such as Transit Oriented Development (TOD) is seen as a possible solution to mitigate these negative effects on the overall livability of the urban area. As part of possibilities for charting a more sustainable urban future, TOD and energy efficient buildings have gained attention in the recent years. However, most research has focused on the contribution of both these sustainable approaches separately. Little research exists that investigates the energy efficiency of recommending sustainable development such as a TOD in an urban area. Hence, this research examines whether a sustainable planning approach such as a TOD has a positive influence on the energy efficiency of its built urban area in comparison to a non- TOD type development.
