A TDMA-Based MAC Protocol for Mitigating Mobility-Caused Packet Collisions in Vehicular Ad Hoc Networks

An autonomous driving environment poses a very stringent requirement for the timely delivery of safety messages in vehicular ad hoc networks (VANETs). Time division multiple access (TDMA)-based medium access control (MAC) protocols are considered a promising solution because of their time-bound message delivery. However, in the event of mobility-caused packet collisions, they may experience an unpredicted and extended delay in delivering messages, which can cause catastrophic accidents. To solve this problem, a distributed TDMA-based MAC protocol with mobility-caused collision mitigation (MCCM-MAC) is presented in this paper. The protocol uses a novel mechanism to detect merging collisions and mitigates them by avoiding subsequent access collisions. One vehicle in the merging collisions retains the time slot, and the others release the slot. The common neighboring vehicles can timely suggest a suitable new time slot for the vacating vehicles, which can avoid access collisions between their packet transmissions. A tie-breakup mechanism is employed to avoid further access collisions. Simulation results show that the proposed protocol reduces packet loss more than the existing methods. Consequently, the average delay between the successfully delivered periodic messages is also reduced.

Differential Requirement for the Cell Wall Integrity Sensor Wsc1p in Diploids Versus Haploids

The primary role of the Cell Wall Integrity Pathway (CWI) in Saccharomyces cerevisiae is monitoring the state of the cell wall in response to general life cycle stresses (growth and mating) and imposed stresses (temperature changes and chemicals). Of the five mechanosensor proteins monitoring cell wall stress, Wsc1p and Mid2p are the most important. We find that WSC1 has a stringent requirement in zygotes and diploids, unlike haploids, and differing from MID2’s role in shmoos. Diploids lacking WSC1 die frequently, independent of mating type. Death is due to loss of cell wall and plasma membrane integrity, which is suppressed by osmotic support. Overexpression of several CWI pathway components suppress wsc1∆ zygotic death, including WSC2, WSC3, and BEM2, as well as the Rho-GAPS, BEM3 and RGD2. Microscopic observations and suppression by BEM2 and BEM3 suggest that wsc1∆ zygotes die during bud emergence. Downstream in the CWI pathway, overexpression of a hyperactive protein kinase C (Pkc1p-R398P) causes growth arrest, and blocks the pheromone response. With moderate levels of Pkc1p-R398P, cells form zygotes and the wsc1∆ defect is suppressed. This work highlights functional differences in the requirement for Wsc1p in diploids Versus haploids and between Mid2p and Wsc1p during mating.

Performance enhancement of GaSb vertical nanowire p-Type MOSFETs on Si by rapid thermal annealing

GaSb is considered as an attractive p-type channel material for future III-V metal-oxide-semiconductor (MOS) technologies, but the processing conditions to utilize the full device potential such as low power logic applications and RF applications still need attention. In this work, applying rapid thermal annealing (RTA) to nanoscale GaSb vertical nanowire p-type MOSFETs, we have improved the average peak transconductance (g m,peak) by 50% among 28 devices and achieved 70 µS/µm at V DS = – 0.5 V in a device with 200-nm gate length. In addition, a low subthreshold swing down to 144 mV/dec as well as an off-current below 5 nA/µm which refers to the off-current specification in low-operation-power (LOP) condition has been obtained. Based on the statistical analysis, the results show a great enhancement in both on- and off-state performance with respect to previous work mainly due to the improved electrostatics and contacts after RTA, leading to a potential in low-power logic applications. We have also examined a short channel device with L g = 80 nm in RTA, which shows an increased gm,peak up to 149 µS/µm at V DS = – 0.5 V as well as a low on-resistance of 4.7 kΩ·µm. The potential of further enhancement in g m via RTA offer a good alternative to obtain high-performance devices for RF applications which have less stringent requirement for off-state performance. Our results indicate that post-fabrication annealing provides a great option to improve the performance of GaSb-based p-type devices with different structures for various applications.

Deep Categorization of Blood Cells u sing Depthwise Convolutions

Modern-day computation has become indispensable in the healthcare industry. From medical image processing to cost reduction, Artificial Intelligence has proved its significance in solving complex healthcare problems. One of the primary areas in which it can be of greater use in hematology. Categorization of white-blood cells is imperative to pre-identify abnormalities. Through this paper, we collected image samples for 4 major White Blood cell groups, which are Neutrophils, Lymphocytes, Monocytes, and Eosinophils. The aim of this research is to put forward an intelligent system that efficiently alleviates the stringent requirement of a cytological study. The proposed system classifies 4 white-blood-cell types based on their morphological variation. With the experimental modulations that we chose to integrate, the presented model attained an accuracy of 97%.

Atomic layer deposition (ALD) for environmental protection and whisker mitigation of electronic assemblies

In this study, we demonstrate how metal-oxide thin-film conformal coatings grown by atomic layer deposition (ALD) can be exploited as an effective approach to mitigate tin whisker growth on printed circuit boards. First, we study the effect of different ALD coatings and process parameters on Sn–Cu-electroplated test coupons, by combining optical imaging and scanning electron microscopy and evaluating whisker distribution on the surface. On these samples, we found that one important parameter in mitigating whisker growth is the time interval between electroplating and the ALD coating process (pre-coat time), which should be kept of the order of few days (2, based on our results). Atomic layer-deposited coatings were also found to be effective toward whisker formation in different storage conditions. Furthermore, we show that ALD coating is also effective in limiting the need for outgassing of electronic assemblies (PCBAs), which is an additional stringent requirement for applications in space industry. Our experimental results thus demonstrated that atomic layer deposition is a suitable technique for aerospace applications, both in terms of degassing and whisker mitigation.

Four-pronged decision support framework for implementing industrialized construction projects

Purpose Industrialized construction (IC) is promoted to address some of the ills associated with the processes and products of the traditional construction approach. With several successful projects, IC is progressively becoming a preferred alternative construction approach and spurred the interest of contractors, developers and housing authorities in the technology. Increasingly, these stakeholders are keen to ascertain the compatibility and feasibility of using IC in their projects. This paper aims to develop a knowledge-based decision support framework for implementing industrialized construction projects (ICPs) that can facilitate better and informed decision-making when deciding to implement ICPs. Design/methodology/approach A comprehensive literature review was implemented to recruit 40 decision support factors (DSFs) and grouped into project requirements, location and site attribute, labour considerations and organizational factors. A 3-member expert panel validated the relevance of 35 DSFs, which became candidates for a structured questionnaire survey of experts in 18 countries. Statistical techniques are used to evaluate and prioritize the DSFs, leading to the development of a conceptual framework. Findings Statistical analysis revealed 33 significant DSFs. The top five most significant factors that could influence the decision to implement IC in a project include a stringent requirement for project quality control, suitability of the design for IC, organizational readiness and competencies in ICPs, client receptivity to IC and the need to minimize field construction time. A framework of project requirements, location and site attributes, labour considerations and organizational factors was proposed as decision support. Practical implications The proposed framework may help to inform decision-making regarding the implementation of IC in a project. It has wider applicability because it includes technical, managerial and operational aspects of and the required competencies for IC, which are shared between project types and territories. The prioritized DSFs could be used as a guide when implementing IC, especially in countries where bespoke decision support systems cannot be developed. Originality/value The paper delineated the most important DSFs that are shared between IC project types and territories and can be used to investigate the compatibility of using IC in a proposed project. This research constitutes the first exclusive attempt at delineating, quantifying and ranking the sets of decision-making factors, drawing on international data set and contributes to the empirical checklist of DSFs for ICPs.

REMODELING OF MILITARY STRUCTURES – A STRINGENT REQUIREMENT FOR INCREASING MOBILITY AND COUNTERMOBILITY

Modern military conflicts have proved that military actions are characterized by very rapid situational changes. Commanders and staffs must know how to react promptly to these changes and order, according to the situation, the measures to be taken, knowing that their decisions will coordinate the combat actions of the forces according to the missions received. The tendency of modern armies to increase the mobility of their troops by technological up-grades in short time, which incorporated the latest developments in science at that time, has been constantly backed up by the tendency to find the most economical and effective ways to reduce the maneuverability of opposing troops. These trends generated by the high dynamics of the current confrontation environment have practically imposed the need for the permanent remodeling of the military structures having as final goal the obtaining of the victory in the military operations/actions.

A Multi-Core Controller for an Embedded AI System Supporting Parallel Recognition

Recent advances in artificial intelligence (AI) technology encourage the adoption of AI systems for various applications. In most deployments, AI-based computing systems adopt the architecture in which the central server processes most of the data. This characteristic makes the system use a high amount of network bandwidth and can cause security issues. In order to overcome these issues, a new AI model called federated learning was presented. Federated learning adopts an architecture in which the clients take care of data training and transmit only the trained result to the central server. As the data training from the client abstracts and reduces the original data, the system operates with reduced network resources and reinforced data security. A system with federated learning supports a variety of client systems. To build an AI system with resource-limited client systems, composing the client system with multiple embedded AI processors is valid. For realizing the system with this architecture, introducing a controller to arbitrate and utilize the AI processors becomes a stringent requirement. In this paper, we propose an embedded AI system for federated learning that can be composed flexibly with the AI core depending on the application. In order to realize the proposed system, we designed a controller for multiple AI cores and implemented it on a field-programmable gate array (FPGA). The operation of the designed controller was verified through image and speech applications, and the performance was verified through a simulator.

Elements that Contribute to the Efficiency of Communication Between Teacher and Student

Communication skills are one of the most important educational elements today. Current education has already included communication competencies as independent objectives in the education of young generations. Communication is a multidisciplinary existential basis and that is why its understanding is not easy, and must be approached scientifically, conceptually and structurally. This paper aims to emphasize the importance of communication in the teaching-learning process and its direct correlation with school success but also with success in life. Teachers need communication more than anyone. Their verbal communication occupies 70% of a class lesson (Haslett, 1987). The appeal to the elements of emotional intelligence, to the motivation / interests of the students, becomes a necessity and at the same time they are constituted as factors that can improve and make efficient the didactic communication. In this paper we will analyze the main functions of teacher-student communication (guidance, information and thought challenge). There are described other elements that can also contribute to better communication in the classroom: active presentation of topics, providing summaries, resumption of main ideas, clarity of presentation (sentence logic, examples and explanations), assessment of comprehension deficiencies and their correction, frequently asked questions. All these aspects have proved, through the studies carried out, that they are positively correlated with the students’ results. The verbal communication of the educator is always accompanied by the elements of non-verbal communication that have an important role in achieving an effective instructive-educational process. In this regard, we can mention a few essential components: posture, gestures, facial expressions, style of dressing, tone of voice, all of which can incite or divert the listener’s attention. Another important element in effectiveness of the didactic communication is the knowledge of the cultural, economic and social environment from which the students come, their specific characteristics. The interaction will be more plausible, accessible to the student, when well known, culturally familiar aspects are inserted in the complex process of teacher-student communication. The integration of cultural diversity in didactic communication has become a stringent requirement of modern education.

Water-Assisted and Protein-Initiated Ring-Opening Polymerization of Proline N-Carboxyanhydride

<p>The production of poly-_L-proline (PLP) via the ring-opening polymerization (ROP) of _L-proline <i>N</i>-carboxyanhydride (ProNCA) is challenging due to a combination of factors, including the stringent requirement of moisture-free conditions, slow monomer conversion, poor control of the molar mass, and premature precipitation of the product in the form of polyproline type I helix. Here, we report water-assisted ROP of ProNCA, which affords well-defined PLP in polyproline II helix in 2-5 minutes. Density functional theory reveals an as-yet-unreported role of water in facilitating proton shift that significantly lowered the energy barrier of the chain propagation. Protein-mediated ROP of ProNCA conveniently affords various protein-PLP conjugates via a grafting-from approach. PLP conjugation not only preserves the biological activities of the native proteins, but also enhances the stability of proteins against extreme conditions. This work provides a simple means and new mechanistic insight to solve a longstanding problem in PLP synthesis and will offer valuable guidance for the development of water-resistant ROP of other NCAs. The facile access of PLP can greatly boost the application potentials of PLP-based functional materials.<b></b></p>