Development and Testing of Braking and Acceleration Features for Vehicle Advanced Driver Assistance System

Traffic congestion is a constant problem for cities worldwide. The human driving inefficiency and poor urban planning and development contribute to traffic buildup and travel discomfort. An example of human inefficiency is the phantom traffic jam, which is caused by unnecessary braking, causing traffic to slow down, and eventually coming to a stop. In this study, a brake and acceleration feature (BAF) for the advanced driver assistance system (ADAS) is proposed to mitigate the effects of the phantom traffic phenomenon. In its initial stage, the BAF provides a heads-up display that gives information on how much braking and acceleration input is needed to maintain smooth driving conditions, i.e., without sudden acceleration or deceleration, while observing a safe distance from the vehicle in front. BAF employs a fuzzy logic controller that takes distance information from a light detection and ranging (LIDAR) sensor and the vehicle’s instantaneous speed from the engine control unit (ECU). It then calculates the corresponding percentage value of needed acceleration and braking in order to maintain travel objectives of smooth and safe-distance travel. Empirical results show that the system suggests acceleration and braking values slightly higher than the driver’s actual inputs and can achieve 90% accuracy overall

Predicting Converter Utilization Convergence under Various Dynamic Loading Conditions of Paralleled Converters

Abstract-In this paper, converter utilization equalization under various dynamic loading conditions experienced by parallel buck converters were observed. Equalization of converter utilization is ensured by using fuzzy logic control while output voltage regulation and current sharing between converters is maintained by employing sliding mode control. This research work has also contributed the derivation of the working equation in determining the converter's utilization point of equalization even in dynamic loading. Simulation results have confirmed that the value solved from the working equations are correct and equal to the value of the utilizations each of the converters converged under a given dynamic load

Academic freedom: in justification of a universal ideal

This paper examines the justification for, and benefits of, academic freedom to academics, students, universities and the world at large. The paper surveys the development of the concept of academic freedom within Europe, more especially the impact of the reforms at the University of Berlin instigated by Wilhelm von Humboldt. Following from this, the paper examines the reasons why the various facets of academic freedom are important and why the principle should continue to be supported

Speaker feature modeling utilizing constrained maximum likelihood linear regression and Gaussian mixture models

This paper describes a speaker recognition system based on feature extraction utilizing the constrained maximum likelihood linear regression (CMLLR) speaker adaptation, while using Gaussian mixture models (GMM) to model the speaker and background models. For the input acoustic signals, the cepstral features are derived to highlight the differences between test and training utterances. The CLSU dataset is used to test the efficiency and performance of the proposed CMLLR, Support Vector Machine, and GMM methods for modeling the speaker’s voice by characterizing the speaker features. © 2020, World Academy of Research in Science and Engineering. All rights reserved

Reducing beat frequency oscillation in a two-phase sliding mode-controlled voltage regulator module

During static and dynamic loading conditions, voltage regulator modules (VRMs) are expected to provide regulated voltage with minimal ripple even at high current requirement. Compared to regular power supplies, VRMs repetitively experience high-frequency loading conditions that is greatly dependent on the software running in the processor utilizing them. In the scenario that when the transient load frequency is near the VRM’s switching frequency, high-magnitude and low-frequency oscillations are observed at the phase currents. This phenomenon is called the beat frequency oscillation. In this study, the sliding mode control principle is employed to both the voltage and current share loops of the VRM to reduce the phase currents’ beat frequency oscillations. A fixed frequency sliding mode controller is derived and extensively evaluated using the PSIM simulator. Our results show that while maintaining equal load sharing among VRMs at less than 5% sharing error and various types of loading conditions, the sliding mode controller can reduce the beat frequency oscillation phenomenon to 20 kHz at maximum with reduced peak current values. The output voltage is also regulated within the desired ±1.65% band. © 2019 Institute of Advanced Engineering and Science. All rights reserved

Speed and torque control of a DC shunt motor

This paper discusses the speed and torque control of a shunt DC motor through MATLAB Simulink simulations. The DC shunt motor is 120Vdc with rated speed of 1800 revolutions per minute. Blocks pertinent to the control of the DC motor are modeled using basic blocks found in the Simulink library

An IoT-based smart orchard monitoring system by employing wireless sensor networks

In this study, an IoT-based smart orchard monitoring is proposed to gather and transmit environment data from a sensor node to a central node for necessary and relevant actuation in order to have good produce at the soonest amount of time. Wireless sensor motes are deployed based on a simple linear pattern across a square farm and only require the minimum set of specifications to monitor its surrounding. On the other hand, the central nodes will require more processing power, memory and power requirements. Sensor and central nodes communicate in a line-of-sight method and follows a deterministic routing table based on the sensor node’s four neighbors. Throughput, latency, and energy consumption results are presented to allow designers and farmers consideration and freedom on how to select which routing protocol can be used to achieve their target objectives. © BEIESP

Employing mobility traces\u27 findings in deploying roadside units in an urban setup

The city infrastructure is an integral part of vehicular ad-hoc networks and intelligent transportation systems. One of the key infrastructures is the roadside unit (RSU) which can vastly improve the efficiency and coverage of data dissemination and information exchange in the vehicular network when deployed judiciously. RSU can also provide real-time traffic control, safety and road services to drivers. In this paper, we study how to strategically deploy RSUs in candidate junctions in a city layout by employing findings from taxi GPS traces such as the total daily number of vehicle-to-infrastructure (V2I) contacts, transmissions, transmitted file size, and the average space speed. A Consolidated Weighted Mean Approach, ConsWMA, based from four practical methods for deploying RSUs, is proposed to maximize the amount of V2I contacts. We observe that these mobility traces\u27 findings, when set as deployment criteria, can reduce the needed number of RSUs to be deployed and the missing V2I contacts. Simulation results show that when nine out of the 40 possible RSU locations are allocated in the first two rings of Beijing City, a 95% daily average V2I contacts is attained, thereby making information dissemination feasible. ConsWMA also provides at least 11% more V2I contacts when compared to two other deployment methods. © 2019 IEEE

Stairway control of buck power supplies in parallel configuration

Power supplies are configured in parallel to provide higher current demand to the load, while achieving modularity by using low-power power converter modules. However, in some cases, redundancy of power converters is installed to provide safety in case of overload and breakdown of a module. In such case, the wear and tear of all modules vary depending on what the load side present. We present in this work a basic control for ensuring that power module utilization is approximately equal for all modules in the parallel configuration. Our proposed control methodology turns ON/OFF a module based on the current load scenario. By switching the utilization of these modules, our control can display a stairway waveform while regulating the output voltage and supplying the necessary current. We demonstrate our control structure through simulations of various static and dynamic loading conditions, while considering error in current sharing of working power modules. © 2006-2019 Asian Research Publishing Network (ARPN)