Backward Compatibility Research Articles

Modernizing the NEURON Simulator for Sustainability, Portability, and Performance.

The need for reproducible, credible, multiscale biological modeling has led to the development of standardized simulation platforms, such as the widely-used NEURON environment for computational neuroscience. Developing and maintaining NEURON over several decades has required attention to the competing needs of backwards compatibility, evolving computer architectures, the addition of new scales and physical processes, accessibility to new users, and efficiency and flexibility for specialists. In order to meet these challenges, we have now substantially modernized NEURON, providing continuous integration, an improved build system and release workflow, and better documentation. With the help of a new source-to-source compiler of the NMODL domain-specific language we have enhanced NEURON's ability to run efficiently, via the CoreNEURON simulation engine, on a variety of hardware platforms, including GPUs. Through the implementation of an optimized in-memory transfer mechanism this performance optimized backend is made easily accessible to users, providing training and model-development paths from laptop to workstation to supercomputer and cloud platform. Similarly, we have been able to accelerate NEURON's reaction-diffusion simulation performance through the use of just-in-time compilation. We show that these efforts have led to a growing developer base, a simpler and more robust software distribution, a wider range of supported computer architectures, a better integration of NEURON with other scientific workflows, and substantially improved performance for the simulation of biophysical and biochemical models.

A Dual Barcoding Approach to Bacterial Strain Nomenclature: Genomic Taxonomy of Klebsiella pneumoniae Strains.

Sublineages (SLs) within microbial species can differ widely in their ecology and pathogenicity, and their precise definition is important in basic research and for industrial or public health applications. Widely accepted strategies to define SLs are currently missing, which confuses communication in population biology and epidemiological surveillance. Here, we propose a broadly applicable genomic classification and nomenclature approach for bacterial strains, using the prominent public health threat Klebsiella pneumoniae as a model. Based on a 629-gene core genome multilocus sequence typing (cgMLST) scheme, we devised a dual barcoding system that combines multilevel single linkage (MLSL) clustering and life identification numbers (LINs). Phylogenetic and clustering analyses of >7,000 genome sequences captured population structure discontinuities, which were used to guide the definition of 10 infraspecific genetic dissimilarity thresholds. The widely used 7-gene multilocus sequence typing (MLST) nomenclature was mapped onto MLSL SLs (threshold: 190 allelic mismatches) and clonal group (threshold: 43) identifiers for backwards nomenclature compatibility. The taxonomy is publicly accessible through a community-curated platform (https://bigsdb.pasteur.fr/klebsiella), which also enables external users’ genomic sequences identification. The proposed strain taxonomy combines two phylogenetically informative barcode systems that provide full stability (LIN codes) and nomenclatural continuity with previous nomenclature (MLSL). This species-specific dual barcoding strategy for the genomic taxonomy of microbial strains is broadly applicable and should contribute to unify global and cross-sector collaborative knowledge on the emergence and microevolution of bacterial pathogens.

Modeling Multigate Negative Capacitance Transistors With Self-Heating Effects

A unified model for multigate negative capacitance transistors with self-heating effects (SHEs) is developed. With a metal–ferroelectric–insulator–semiconductor (MFIS) structure, thermal effects result in different temperature rises in the channel and ferroelectric layer. A gate control equation for the double-gate and gate-all-around MFIS structures is developed, on top of which both the current–voltage and charge–voltage characteristics are covered. The formulations describe dependences of ferroelectric layer thickness, with backward compatibility for MOSFETs. A unified thermal network is then proposed for SHE, capturing the essential physics of couplings between ferroelectric temperature and conduction current. The model has been verified with TCAD simulations and implemented for circuit simulations.

The path to proton structure at 1% accuracy

We present a new set of parton distribution functions (PDFs) based on a fully global dataset and machine learning techniques: NNPDF4.0. We expand the NNPDF3.1 determination with 44 new datasets, mostly from the LHC. We derive a novel methodology through hyperparameter optimization, leading to an efficient fitting algorithm built upon stochastic gradient descent. We use NNLO QCD calculations and account for NLO electroweak corrections and nuclear uncertainties. Theoretical improvements in the PDF description include a systematic implementation of positivity constraints and integrability of sum rules. We validate our methodology by means of closure tests and “future tests” (i.e. tests of backward and forward data compatibility), and assess its stability, specifically upon changes of PDF parametrization basis. We study the internal compatibility of our dataset, and investigate the dependence of results both upon the choice of input dataset and of fitting methodology. We perform a first study of the phenomenological implications of NNPDF4.0 on representative LHC processes. The software framework used to produce NNPDF4.0 is made available as an open-source package together with documentation and examples.

A CASE STUDY OF VARIOUS WIRELESS NETWORK SIMULATION TOOLS

4G is the fastest developing system in the history of mobile communication networks. Network connectivity is paramount for all kinds of big enterprises. 4G not only provides super-fast connectivity to millions of users, but can also act as an enterprise network connectivity enabler and it has inherent advantages such as higher bandwidth, low latency, higher spectrum efficiency along with backward compatibility and future proofing. The design of the 4G based Long Term Evolution physical network provides the required flexibility for optimization during the development phase. In this paper LTE Network related supporting simulation tools is presented to demonstrate the need of Hardware co-simulation of the LTE system. After the feasibility analysis, the importance of the model is to be ported Field Programmable Gate Array platform is examined in survey in detail with the supporting inferences along with the comparison of different wireless network simulators suitable for LTE.

IDHOCNET-A Novel Protocol Stack and Architecture for Ad hoc Networks

Presently employed Internet Protocol (IP) stack possesses number of architectural problems. The issues like Dual/Overriding role of IP addresses, mobility, multi-homing etc are the limitations for the infrastructure oriented networks which even have support of Dynamic Host Configuration Protocol (DHCP), Domain Name System (DNS), Network Address Translation (NAT) servers, etc. Such issues are extremely complex to handle in the case of multi-hop wireless ad hoc networks which lack the support of any infrastructure component. The contemporary research direction for the improvement of present Internet architecture mainly focuses on the use of real identifiers instead of IP addresses for host identification in the network. However, the proposed architectures mostly discuss the infrastructure oriented network models and minimal research has been conducted in the direction of proposals for ad hoc networks. In this paper we provide a thorough discussion on the practical usage issues of IP based ad hoc network implementation. In order to resolve the present limitations of ad hoc networks, we describe an implementation of a novel identifier based ad hoc network protocol stack and architecture known as IDHOCNET (Identifier based ad hoc network). The architecture proposes a novel paradigm of identifier based applications for multi-hop wireless ad hoc environment. The proposed system further provides backward compatibility to support co-existence with IP based applications. As a proof of concept, the architecture has been implemented on Linux platform with WiFi interfaces. Various practical scenarios with architectural insight are presented to demonstrate the practicability of the proposed approach.

The Data Acquisition System for the ATLAS Tile Calorimeter Phase-II Upgrade Demonstrator

The tile calorimeter (TileCal) is the central hadronic calorimeter of the ATLAS experiment at the large hadron collider (LHC). In 2025, the LHC will be upgraded leading to the high luminosity LHC (HL-LHC). The HL-LHC will deliver an instantaneous luminosity up to seven times larger than the LHC nominal luminosity. The ATLAS Phase-II upgrade (2025–2027) will accommodate the subdetectors to the HL-LHC requirements. As part of this upgrade, the majority of the TileCal on-detector and off-detector electronics will be replaced using a new readout strategy, where the on-detector electronics will digitize and transmit digitized detector data to the off-detector electronics at the bunch crossing frequency (40 MHz). In the counting rooms, the off-detector electronics will compute reconstructed trigger objects for the first-level trigger and will store the digitized samples in pipelined buffers until the reception of a trigger acceptance signal. The off-detector electronics will also distribute the LHC clock to the on-detector electronics embedded within the digital data stream. The TileCal Phase-II upgrade project has undertaken an extensive research and development program that includes the development of a Demonstrator module to evaluate the performance of the new clock and readout architecture envisaged for the HL-LHC. The Demonstrator module equipped with the latest version of the on-detector electronics was built and inserted into the ATLAS experiment. The Demonstrator module is operated and read out using a Tile PreProcessor (TilePPr) Demonstrator which enables backward compatibility with the present ATLAS Trigger and Data AcQuisition (TDAQ), and the timing, trigger, and command (TTC) systems. This article describes in detail the main hardware and firmware components of the clock distribution and data acquisition systems for the Demonstrator module, focusing on the TilePPr Demonstrator.

CAN Bus Message Authentication via Co-Channel RF Watermark

Over the past decade, consumer vehicles have increasingly begun to resemble computers on wheels, with many newer vehicles containing over 100 independent electronic control units (ECU) that make independent decisions within the vehicle. Cost and power constraints for the vehicle significantly constrain processing capabilities and limitations on practical cybersecurity measures that may be employed in the vehicle today. Also, as automotive manufacturers are continuous integrators, many legacy communications links within vehicles were originally designed as standalone entities that assumed internal trust of communications between ECUs by virtue of closed bus structures and an emphasis on reliability, but not security. This paper presents a low-cost authentication mechanism to significantly improve message validation on wired message buses such as the Controller Area Network (CAN) bus by employing a co-channel underlay watermark that arrives time-aligned with the primary bus messages. Concept validation using a gate-level Simulink / HDL Coder simulation provided initial feasibility, while a complete CAN bus hardware testbed was constructed with a custom CAN transceiver built on a Red Pitaya software defined radio (SDR) connected to multiple commercial CAN transceivers to validate backwards compatibility. This testbed incorporates a custom transmission security (TRANSEC) engine that supports dynamic variation of the watermark, further improving security during deployment. Finally, this custom CAN testbed with the watermarking CAN transceiver was tested across a range of operational conditions, with initial performance results presented and discussed. Future work describes potential for near-term ruggedization and productization of the watermarking CAN transceiver.

Six Critical Challenges for 6G Wireless Systems: A Summary and Some Solutions

Numerous articles are now appearing on 6G wireless systems, covering different aspects, ranging from vision, architecture, and applications to technology breakthroughs. With cellular systems in mind, this article presents six critical, yet fundamental, challenges that must be overcome before the development and deployment of 6G systems. These include opening the subterahertz spectrum for increased bandwidths and the ability to utilize these bandwidths, pushing the limits of semiconductor technologies for operation within these bands, developing transceiver designs and architectures to realize the high peak data rates, and achieving submillisecond latencies at the network level to achieve 6G key performance indicators (KPIs). Additionally, since 6G systems will not be introduced in a greenfield environment, backward compatibility with existing systems is discussed. Where possible, we present practical solutions to realize the identified challenges.

Modelling Surround‐aware Contrast Sensitivity for HDR Displays

AbstractDespite advances in display technology, many existing applications rely on psychophysical datasets of human perception gathered using older, sometimes outdated displays. As a result, there exists the underlying assumption that such measurements can be carried over to the new viewing conditions of more modern technology. We have conducted a series of psychophysical experiments to explore contrast sensitivity using a state‐of‐the‐art HDR display, taking into account not only the spatial frequency and luminance of the stimuli but also their surrounding luminance levels. From our data, we have derived a novel surround‐aware contrast sensitivity function (CSF), which predicts human contrast sensitivity more accurately. We additionally provide a practical version that retains the benefits of our full model, while enabling easy backward compatibility and consistently producing good results across many existing applications that make use of CSF models. We show examples of effective HDR video compression using a transfer function derived from our CSF, tone‐mapping and improved accuracy in visual difference prediction.

The 21st Century Systems: An Updated Vision of Continuous-Time Fractional Models

This paper presents the continuous-time fractional linear systems and their main properties. Two particular classes of models are introduced: the fractional autoregressive-moving average type and the tempered linear system. For both classes, the computations of the impulse response, transfer function, and frequency response are discussed. It is shown that such systems can have integer and fractional components. From the integer component we deduce the stability. The fractional order component is always stable. The initial-condition problem is analyzed and it is verified that it depends on the structure of the system. For a correct definition and backward compatibility with classic systems, suitable fractional derivatives are also introduced. The Grünwald-Letnikov and Liouville derivatives, as well as the corresponding tempered versions, are formulated.

Intelligent Approach to Network Device Migration Planning towards Software-Defined IPv6 Networks.

Internet and telecom service providers worldwide are facing financial sustainability issues in migrating their existing legacy IPv4 networking system due to backward compatibility issues with the latest generation networking paradigms viz. Internet protocol version 6 (IPv6) and software-defined networking (SDN). Bench marking of existing networking devices is required to identify their status whether the existing running devices are upgradable or need replacement to make them operable with SDN and IPv6 networking so that internet and telecom service providers can properly plan their network migration to optimize capital and operational expenditures for future sustainability. In this paper, we implement “adaptive neuro fuzzy inference system (ANFIS)”, a well-known intelligent approach for network device status identification to classify whether a network device is upgradable or requires replacement. Similarly, we establish a knowledge base (KB) system to store the information of device internetwork operating system (IoS)/firmware version, its SDN, and IPv6 support with end-of-life and end-of-support. For input to ANFIS, device performance metrics such as average CPU utilization, throughput, and memory capacity are retrieved and mapped with data from KB. We run the experiment with other well-known classification methods, for example, support vector machine (SVM), fine tree, and liner regression to compare performance results with ANFIS. The comparative results show that the ANFIS-based classification approach is more accurate and optimal than other methods. For service providers with a large number of network devices, this approach assists them to properly classify the device and make a decision for the smooth transitioning to SDN-enabled IPv6 networks.

Securing the Automatic Identification System (AIS): Using public key cryptography to prevent spoofing whilst retaining backwards compatibility

AbstractThe civilian Automatic Identification System (AIS) has no inherent protection against spoofing. Spoofed AIS messages have the potential to interfere with the safe navigation of a vessel by, amongst other approaches, spoofing maritime virtual aids to navigation and/or differential global navigation satellite system (DGNSS) correction data conveyed across it. Acting maliciously, a single transmitter may spoof thousands of AIS messages per minute with the potential to cause considerable nuisance; compromising information provided by AIS intended to enhance the mariner's situational awareness. This work describes an approach to authenticate AIS messages using public key cryptography (PKC) and thus provide unequivocal evidence that AIS messages originate from genuine sources and so can be trusted. Improvements to the proposed AIS authentication scheme are identified which address a security weakness and help avoid false positives to spoofing caused by changes to message syntax. A channel loading investigation concludes that sufficient bandwidth is available to routinely authenticate all AIS messages whilst retaining backwards compatibility by carrying PKC ‘digital signatures’ in a separate VHF Data Exchange System (VDES) side channel.

A Case Study of Network Mobility (NEMO-BSP) Integration with Leo Constellation System

Introduction: This manuscript is explicating the mutual compatibility of boot modes in a computer system and partition-ing styles of Hard Disk Drive. Most of us are familiar with these terms and know a little about these. Method: This manuscript contains the ample information about the boot modes of a computer system and partitioning styles of Hard Disk Drive (HDD) and their related configuration through which we get to know about their configuration and endurability. It also contains some practically verified case studies of the problems which occur due to the wrong con-figuration of boot modes and partitioning styles, though there are lot more but the most common ones are discussed along with their solutions. Result: In order to achieve the compatibility, it might require to convert the primary HDD into either GPT or MBR parti-tioning schemes. It should be marked that this interconversion wipes data on HDD, so cautiously the data on the hard drive must be backed-up before any conversion process. Conclusion: The information contained had been practically verified and is helpful in coping with the newer technology trends which contains more features along with backward compatibility. Keywords: Mobile IPv4, Mobile IPv6, NEMO, QoS, NS-2. Discussion: Right now passengers of flight are forced to interact with flight’s pre-recorded entertainment system. Most of the passenger airlines do not allow a passenger to use the internet or any other type of interaction with the ground while during the flight. They force passengers to even switch their mobile to FLIGHT MODE so that there is no active commu-nication between a passenger and the remaining world.

연접 및 자름 기반 코드 설계를 위한 후보 골드 코드 군 선택 기법

In GNSSs (Global Navigation Satellite Systems), it is common to use codes with lengths in multiples of 1023 to maintain backward compatibility with the preexisting GNSSs. In general, there is no well-defined family of codes whose length is in multiples of 1023, and thus, codes are usually designed with concatenation or truncation in well-known code families. However, there is no golden rule to choose a mother code family for code design. In this paper, we propose a mother Gold code family selection scheme suitable for code design with concatenation or truncation. In the proposed scheme, a preferable mother Gold code is chosen by investigating the cumulative distributions of the autocorrelation sidelobes of randomly generated codes with concatenation and truncation of codes in the candidate mother Gold codes. With the proposed scheme, it is possible to choose an optimal mother Gold code family with less complexity in a short time.

Innovative Energy Management System for Mobile Processors Power Consumption with Integration of Predictive Neural Network Models

At the present stage of information technologies development in the field of portable devices implementation one of the perspective direction is the development of software and hardware to optimise the consumption of energy resources in mobile processors. Modern solutions are aimed at continuous improvement of methods to reduce power consumption along with increasing the performance of devices, but the problem of limited time interval of portable devices active use is still relevant. Existing solutions are aimed at using various energy-dependent methods in the kernel configuration – I/O scheduler governors, TCP overload algorithms, as well as additional entropy distribution systems and memory release algorithms. The solutions considered involve a system of aggressive behaviour based on the use of user-driven methods to terminate energy demanding processes in the system. The purpose of this study is to overcome the problems under consideration by developing a cross-platform algorithmic approach, which is based on the tracking of the energy consumption processes in the kernel, taking into account system calls and background activity in the system. A distinctive feature of the proposed solution is the use of a neural network training sample for the processes of tracking user behaviour, which affects the reduction of the CPU load by completing side processes and increasing the time interval of battery performance. To implement the project, root access to the system was also used, assuming full-function access to the system kernel. Another feature of the implemented algorithm is backwards compatibility of the work with mobile processors, which allows to organise work on mobile devices.

Implementation of tourism circuit concept in an android-based tourist navigation application through A* algorithm

Circuit tourism allows for inclusive growth of tourism since it allows for multi-site visits. Normally three or more tourist attractions are linked together in a tour of the tourist’s choosing. The main objective of this study is to develop an android-based application for searching tourist spots in Los Baños, Laguna, Philippines that is also capable of recommending succeeding places to visit using A* algorithm. Upon development of the application, this paper proves that A* algorithm can be used to recommend another tourist spot by analyzing the distance of the tourist spots near the user, and the most convenient routes through which they can be reached. Based on backward and forward compatibility testing, the application is operating system friendly, since it can be used in lower versions of android. Further, it is shown in the users’ evaluation that the application is acceptable to the locals of Los Baños, Laguna, Philippines. The application also contributes to advertising other tourist spots in the said municipality, specially those who were not so popular to the tourists.

Research on an invasive and low-frequency power consumption data acquisition method

Aiming at the large-scale, compatibility and reliability problems faced by the data acquisition engineering for power consumption in the industrial field, for reducing the complexity and cost of the data acquisition engineering, and improving the quality, maintainability, scalability and manageability of the data acquisition, an engineering-oriented, intrusive, low-frequency data acquisition scheme for power consumption is proposed. The scheme leverages multi-agent networking technology to solve the large-scale problem, utilizes the communication driver of the dynamic loading adapter mode to tackle the compatibility trouble. Furthermore, the local storage, breakpoint retransmission, flow control, automatic recovery, automatic connection, and time synchronization are combined to solve the reliability issue. Engineering tests show that the proposed scheme possesses the significant backward compatibility characteristics, which can effectively reduce the complexity and cost of data acquisition engineering for power consumption, and significantly improve the quality, maintainability, scalability and manageability of data acquisition.

Sliding Group Window with Rebacking off for Collision Avoidance in High-Efficiency Wireless Networks

It is difficult for wireless local area networks (WLANs), IEEE 802.11ax high-efficiency WLAN (HEW), to join next-generation innovations such as 5th generation (5G) and Internet of Things (IoT) because they still have their conventional channel access mechanism as their essential medium access control (MAC) protocol. The MAC protocol uses a traditional binary exponential backoff (BEB) algorithm to access channel resources that depend on the noncognitive increment of contention parameters for collision avoidance. In BEB, the collision issue increases with the increase in connected devices in the network due to a fixed contention window size. The larger the size of the network, the larger the collision in the network. To avoid such a circumstance, in this paper, we propose a sliding group window (sGW) mechanism dependent on collision-point assessment in order to improve the performance of MAC protocol for HEW. The proposed algorithm additionally presents a rebacking off for collision avoidance (ReBOCA) system for sGW, which combines the uniform dispersion of the contention parameters. This variation of an ordinary backoff algorithm permits the reasonable sliding of the user groups in the case of collision. The algorithm explicitly accounts for the peculiarities of dense environments and backward compatibility. Key aspects of the proposed solution include collision-point estimation, rebacking off for collision distribution convergence for fair treatment, and adaptive sliding of group windows to mitigate contention unfairness. We further formulated a closed-form Markov chain model for the performance analysis of our proposed sGW with ReBOCA scheme. Theoretical and practical results prove that our proposed scheme achieved maximal efficiency, even under dense environments. An increase in throughput with a lower packet collision probability was achieved with the proposed mechanism, and the efficiency increased as the number of contending stations increased than compared to traditional BEB performance. Our proposed ReBOCA mechanism enhanced network throughput by 38.18% than compared to the conventional BEB mechanism.

Broadband Full-Duplex Antenna for IEEE 802.11 Protocols

In this letter, a broadband two-port full-duplex (FD) antenna is designed, implemented, and measured. The broadband two-port FD antenna is based on a three-port radiating disk integrated with a broadband balun for differential feeding. The prototype antenna provides more than 30 dB interport isolation for 10 dB return loss bandwidth of 4.9 GHz (2.3–7.2 GHz), moreover, higher than 40 dB interport isolation is achieved for 1.2 GHz bandwidth (3.6–4.8 GHz). The measured peak realized gain achieved is between 2.92–8.26 dBi. To the best of our knowledge, no such a planar antenna in existing literature achieves more than 30 dB interport isolation for such a wide bandwidth. The broadband two-port FD antenna can be used for sub-6 GHz 5G (NR) applications and all Wi-Fi bands including the IEEE 802.11be which requires full-duplexity, wide bandwidth, and backward compatibility.