Frame Format Research Articles

MSync: Physical Layer Frame Synchronization without Preamble Symbols

We present a novel physical layer frame format and a corresponding decoding strategy for energy-constraint single-carrier transceivers, often used in sensor networks and cyber-physical systems. The main advantage of our approach is that decoding does not rely on dedicated preamble symbols, which usually introduce considerable overhead in terms of energy consumption and utilization of the wireless channel. We show that omitting the preamble can be achieved by buffering the signal in the receiver and processing the samples twice; first to synchronize and in a second iteration to decode the actual data. To introduce our approach, we provide a theoretical description, including a discussion of the implications of synchronizing on data symbols instead of optimized preamble sequences. The practical feasibility of the algorithm is shown by simulations and experiments using prototype implementations based on software defined radio. We implemented our algorithm for two technologies, a custom ultra low-power BPSK transceiver and the O-QPSK physical layer of the IEEE 802.15.4 standard. Finally, we present an extension of the algorithm that allows us to reduce the buffered data to a small constant number of samples, making our algorithm applicable to physical layers independent from their maximum frame size.

The Busload Prediction Model of CANFD Based on Mathematical Statistics

A busload prediction models of four kind of frame formats has been established in the paper, the mathematical expectation of the busload for FBFF (FD Base Frame Format), CBFF (Classical Base Frame Format), FEFF(FD Extended Frame Format)and CEFF(Classical Extended Frame Format)is obtained based on the model in order to predict the busload of each message, it can be used for network design. The comparative analysis shows that when the message length is 8 bytes or less, the transmission efficiency of the CBFF is slightly higher than that of the FBFF, while when the message length is between 9 up to 64 bytes, the transmission efficiency of the FBFF is far higher than that of CBFF. The communication bandwidth is greatly increased with flexible data rate, and the longer the message is, the larger the bandwidth will be. The research results have been successfully applied to a variety of vehicle CANFD network design to predict the busload of each message, and application results show that the simulation accuracy is high and the efficiency of CANFD network design is improved effectively.

Fuzzy Based Adaptive Controller for on - Chip Communication

Occurrence of bit error is more when communication takes place in System on chip environment. By employing proper error detection and correction codes the bit error rate can be considerably reduced in On-chip communication. As System on chip involves heterogeneous system the efficiency of communication is improved when reconfigurable multiple coding schemes are preferred. Depending upon the requirements for various subsystem the correct code has to be selected. Due to the variations in input demands based on various subsystems the proper selection of codes become fuzzy in nature. In this paper Fuzzy Controller is designed to select the correct coding scheme. Inputs are given to the fuzzy controller based on the application demand of the user. The input parameters are minimum bit error rate, computational complexity and correlation level of the input data. Fuzzy Controller employs three membership functions and 27 rules to select the appropriate coding scheme. The selected coding scheme should be communicated at the proper time to the decoder. To enable the decoding process selected coding scheme is communicated effectively by using less overhead frame format. To verify the functionality of fuzzy controller random input data sets are used for testing.

Joint Resource Allocation and Software-Based Reconfiguration for Energy-Efficient OFDMA-PONs

The widely deployed passive optical network (PON) is a cost-effective way to create a front/backhaul carrier for ubiquitous wireless access connectivity. To hide the difference of frame formats and multiplexing methods, an orthogonal frequency division multiplexing access PON (OFDMA-PON) was proposed. In upstream transmission, multiple optical network units (ONUs) from the same segment or residential area can transmit data through a shared group of orthogonal low-bitrate subcarriers (SCs) during different time slots (TSs) within the entire transmitting period. In downstream transmission, the optical line terminal can send control signaling of reconfiguring ONUs’ parameters so that SCs can be reallocated among segments, thus sleeping segments with empty data load while ensuring service continuity. Though energy savings can be ensured for upstream data transmission by using existing solutions, only frequency and time domains are involved. It is meaningful for us to make the flexible and energy- efficient configuration of transmitting power and modulation level assigned for ONUs in terms of improving energy efficiency. In this paper, we investigate joint resource allocation for energy-efficient upstream data transmission in OFDMA-PONs, with the help of software-based ONU reconfiguration. We formulate the problem, and the upper bound of energy saving is also derived. To solve the problem in a short span of time, we propose a novel heuristic algorithm whose effectiveness has been demonstrated by extensive simulations.

Mitochondrial genomes organization in alloplasmic lines of sunflower (Helianthus annuus L.) with various types of cytoplasmic male sterility.

BackgroundCytoplasmic male sterility (CMS) is a common phenotype in higher plants, that is often associated with rearrangements in mitochondrial DNA (mtDNA), and is widely used to produce hybrid seeds in a variety of valuable crop species. Investigation of the CMS phenomenon promotes understanding of fundamental issues of nuclear-cytoplasmic interactions in the ontogeny of higher plants. In the present study, we analyzed the structural changes in mitochondrial genomes of three alloplasmic lines of sunflower (Helianthus annuus L.). The investigation was focused on CMS line PET2, as there are very few reports about its mtDNA organization.MethodsThe NGS sequencing, de novo assembly, and annotation of sunflower mitochondrial genomes were performed. The comparative analysis of mtDNA of HA89 fertile line and two HA89 CMS lines (PET1, PET2) occurred.ResultsThe mtDNA of the HA89 fertile line was almost identical to the HA412 line (NC_023337). The comparative analysis of HA89 fertile and CMS (PET1) analog mitochondrial genomes revealed 11,852 bp inversion, 4,732 bp insertion, 451 bp deletion and 18 variant sites. In the mtDNA of HA89 (PET2) CMS line we determined 27.5 kb and 106.5 kb translocations, 711 bp and 3,780 bp deletions, as well as, 5,050 bp and 15,885 bp insertions. There are also 83 polymorphic sites in the PET2 mitochondrial genome, as compared with the fertile line.DiscussionThe observed mitochondrial reorganizations in PET1 resulted in only one new open reading frame formation (orfH522), and PET2 mtDNA rearrangements led to the elimination of orf777, duplication of atp6 gene and appearance of four new ORFs with transcription activity specific for the HA89 (PET2) CMS line—orf645, orf2565, orf228 and orf285. Orf228 and orf285 are the atp9 chimeric ORFs, containing transmembrane domains and possibly may impact on mitochondrial membrane potential. So orf228 and orf285 may be the cause for the appearance of the PET2 CMS phenotype, while the contribution of other mtDNA reorganizations in CMS formation is negligible.

Integrating wireless sensing and decision support technologies for real-time farmland monitoring and support for effective decision making

This paper presents the design of a (i) soil sensing and monitoring wireless sensor network (S2M-WSN) that can sense and monitor farmland with distributed and networked motes equipped with multiple soil sensors and (ii) a prototype decision support system (DSS) that analyses the soil data received from S2M-WSN using statistical methods, stored rules and knowledge base (KB) and auto-transmits alerts on the mobile phones of end-users. Both S2M-WSN and the DSS are integrated through (iii) predefined data frame format and interface protocol. The developed system has been deployed both in the laboratory and real crop conditions for verification, validation and performance evaluation. The system is evaluated by considering various performance metrics such as ambiguities associated with data, data packet delivery rates, support delivery performance ratio, system response time, and resultant plant growth. The developed system empowers the end users with assistance in on-field decision making through relevant advisories and alerts at right time on their mobile phones. The authors believe that the developed system would definitely bridge the information gap between end-users and domain experts for sustainable growth of agriculture.

Forming the Spatial and Institutional Framework of a Communal Town in Medieval Lublin (13th and 14th centuries)

<p class="Normalny1">Artykuł dotyczy formowania się struktur instytucjonalnych i ram przestrzennych późnośredniowiecznego osadnictwa miejskiego, które rozwinęły się w ciągu XIII i XIV stulecia na Wzgórzu Staromiejskim w Lublinie. Autor reinterpretuje ustalenia wcześniejszych badań nad historią Lublina w świetle koncepcji Maxa Webera o zachodnioeuropejskim modelu miasta komunalnego. Miasto tego typu jest charakteryzowane jako autonomiczna jednostka administracyjna, posiadająca własny samorząd gminny i system sądownictwa, jak również jako podmiot terytorialny z określonymi granicami. Autor wyróżnia trzy etapy rozwoju miejskiego w Lublinie: 1) powstanie wczesnomiejskiego osadnictwa wzdłuż dzisiejszej ulicy Grodzkiej, w sąsiedztwie kościoła św. Michała Archanioła w XIII w., 2) wprowadzenie prawa miejskiego i stworzenie nowego układu urbanistycznego przez Władysława Łokietka i Kazimierza Wielkiego, 3) gwałtowne przyspieszenie rozwoju instytucjonalnego i przestrzennego po śmierci Kazimierza.</p>

Sub-Peaks Suppression for DTMB Signal Based Passive Detection Systems

Passive detection is an effective way to monitor the security of the low-altitude airspace. Tsinghua University’s independently developed Digital Television Terrestrial Multimedia Broadcasting (DTMB) signal enjoys a high coverage in China, whereas few studies have addressed the passive detection based on this kind of signal in detail. Ambiguity function is utilized to detect the targets, however there exists sub-peaks caused by the frame format of the DTMB signal. In this paper, we propose a sub-peaks suppression scheme based on DTMB. The influence of the repeated PN sequence and the power difference on sub-peaks generation are analyzed. To tackle the sub-peaks problem, sampled Linear Frequency Modulation signal with the same power of the frame body is adopted to replace the original PN sequence in DTMB reconstruction. The experimental results show that our proposed method can effectively mitigate the sub-peaks problem.

RETRACTED ARTICLE: Development of video compression using EWNS linear transformation and un-repetition simulated contrary based resurgence procedure

In the recent years, video transmission area endures several failures owing to the limited amount of a cutting edge technique to store large sized videos. For this reason, video compression method is used. For compression of videos, frame formation can be done by splitting the video frames by A_Frames, B_Frames and C_Frames. These frames will stay unchanged entire process; it will also utilize the memory for computational purpose. The proposed work consists of 2 phases. In the first phase, Acclimatize Frame Formation (AFF) is used to expand the characteristic of video coding and EWNS linear transformation (ELT) is initiated for substituting B_Frames with neither A_Frame nor C_Frame. In the second phase, un-repetition simulated contrary based resurgence procedure (URSCRP) is proposed for restoration of videos that demonstrates tiny convolution and time necessity together with conservation of restoration feature. Simulation results shows that URSCRP provides better accuracy and optimization compared to other related procedures. URSCRP provides PSNR of 30 dB, accuracy of 98% and minimized amount of elapsed time compared to related procedures.

Performance analysis of an enhanced cooperative MAC protocol in mobile ad hoc networks

In this paper, we evaluate the performance of an enhanced cooperative MAC with busy tone (eBT-COMAC) protocol in mobile ad hoc networks via a combination of theoretical analysis and numerical simulation. Our previously proposed BT-COMAC protocol was enhanced by (1) redesigning the minislots used in the helper node selection procedure; (2) specifying complete frame formats for newly defined and modified control frames; and (3) using a new metric (the received SNR rather than the received power) in the helper node competition. In this eBT-COMAC protocol, cooperation probability is calculated based on a geometric analysis, and a Markov chain-based model is used to derive steady-state probabilities for backoff-related parameters. These results are used to analytically characterize two performance measures: system throughput and channel access delay. Numerical simulation of a mobile wireless network where all communication nodes are assumed to be uniformly distributed in space and move independently based on a random waypoint model is used to validate the analytical results and demonstrate the performance gains achieved by the proposed eBT-COMAC protocol.

Compact Modbus TCP/IP protocol for data acquisition systems based on limited hardware resources

The Modbus TCP/IP has been a standard industry communication protocol and widely utilized for establishing sensor-cloud platforms on the Internet. However, numerous existing data acquisition systems built on traditional single-chip microcontrollers without sufficient resources cannot support it, because the complete Modbus TCP/IP protocol always works dependent on a full operating system which occupies abundant hardware resources. Hence, a compact Modbus TCP/IP protocol is proposed in this work to make it run efficiently and stably even on a resource-limited hardware platform. Firstly, the Modbus TCP/IP protocol stack is analyzed and the refined protocol suite is rebuilt by streamlining the typical TCP/IP suite. Then, specific implementation of every hierarchical layer is respectively presented in detail according to the protocol structure. Besides, the compact protocol is implemented in a traditional microprocessor to validate the feasibility of the scheme. Finally, the performance of the proposed scenario is assessed. The experimental results demonstrate that message packets match the frame format of Modbus TCP/IP protocol and the average bandwidth reaches to 1.15 Mbps. The compact protocol operates stably even based on a traditional microcontroller with only 4-kB RAM and 12-MHz system clock, and no communication congestion or frequent packet loss occurs.

Transposable elements shape the human proteome landscape via formation of cis-acting upstream open reading frames.

Transposons are major drivers of mammalian genome evolution. To obtain new insights into the contribution of transposons to the regulation of protein translation, we here examined how transposons affected the genesis and function of upstream open reading frames (uORFs), which serve as cis-acting elements to regulate translation from annotated ORFs (anORFs) located downstream of the uORFs in eukaryotic mRNAs. Among 39,786 human uORFs, 3,992 had ATG trinucleotides of a transposon origin, termed "transposon-derived upstream ATGs" or TuATGs. Luciferase reporter assays suggested that many TuATGs modulate translation from anORFs. Comparisons with transposon consensus sequences revealed that most TuATGs were generated by nucleotide substitutions in non-ATG trinucleotides of integrated transposons. Among these non-ATG trinucleotides, GTG and ACG were converted into TuATGs more frequently, indicating a CpG methylation-mediated process of TuATG formation. Interestingly, it is likely that this process accelerated human-specific upstream ATG formation within transposon sequences in 5' untranslated regions after divergence between human and nonhuman primates. Methylation-mediated TuATG formation seems to be ongoing in the modern human population and could alter the expression of disease-related proteins. This study shows that transposons have potentially been shaping the human proteome landscape via cis-acting uORF creation.

Pomegranate-Structured Silica/Sulfur Composite Cathodes for High-Performance Lithium-Sulfur Batteries.

Porous materials have many structural advantages for energy storage and conversion devices such as rechargeable batteries, supercapacitors, and fuel cells. When applied as a host material in lithium-sulfur batteries, porous silica materials with a pomegranate-like architecture can not only act as a buffer matrix for accommodating a large volume change of sulfur, but also suppress the polysulfide shuttle effect. The porous silica/sulfur composite cathodes exhibit excellent electrochemical performances including a high specific capacity of 1450 mA h g-1 , a reversible capacity of 82.9 % after 100 cycles at a rate of C/2 (1 C=1672 mA g-1 ) and an extended cyclability over 300 cycles at 1 C-rate. Furthermore, the high polysulfide adsorption property of porous silica has been proven by ex-situ analyses, showing a relationship between the surface area of silica and polysulfide adsorption ability. In particular, the modified porous silica/sulfur composite cathode, which is treated by a deep-lithiation process in the first discharge step, exhibits a highly reversible capacity of 94.5 % at 1C-rate after 300 cycles owing to a formation of lithiated-silica frames and stable solid-electrolyte-interphase layers.

Radiometric Correction of Close-Range Spectral Image Blocks Captured Using an Unmanned Aerial Vehicle with a Radiometric Block Adjustment

Unmanned airborne vehicles (UAV) equipped with novel, miniaturized, 2D frame format hyper- and multispectral cameras make it possible to conduct remote sensing measurements cost-efficiently, with greater accuracy and detail. In the mapping process, the area of interest is covered by multiple, overlapping, small-format 2D images, which provide redundant information about the object. Radiometric correction of spectral image data is important for eliminating any external disturbance from the captured data. Corrections should include sensor, atmosphere and view/illumination geometry (bidirectional reflectance distribution function—BRDF) related disturbances. An additional complication is that UAV remote sensing campaigns are often carried out under difficult conditions, with varying illumination conditions and cloudiness. We have developed a global optimization approach for the radiometric correction of UAV image blocks, a radiometric block adjustment. The objective of this study was to implement and assess a combined adjustment approach, including comprehensive consideration of weighting of various observations. An empirical study was carried out using imagery captured using a hyperspectral 2D frame format camera of winter wheat crops. The dataset included four separate flights captured during a 2.5 h time period under sunny weather conditions. As outputs, we calculated orthophoto mosaics using the most nadir images and sampled multiple-view hyperspectral spectra for vegetation sample points utilizing multiple images in the dataset. The method provided an automated tool for radiometric correction, compensating for efficiently radiometric disturbances in the images. The global homogeneity factor improved from 12–16% to 4–6% with the corrections, and a reduction in disturbances could be observed in the spectra of the object points sampled from multiple overlapping images. Residuals in the grey and white reflectance panels were less than 5% of the reflectance for most of the spectral bands.

A Cross-Layer-Aware FDD/TDD Carrier Aggregation Framework for LTE-A Networks

In this paper, we study the aggregation between the frequency division duplex and time division duplex (TDD) spectrum bands within the context of 3GPP LTE-A system. To be specific, we first provide a cross-layer design analysis to obtain the achievable throughput using the TDD mode for transmission in LTE-A system. Under particular QoS requirements and certain channel conditions, the achievable throughput is derived and evaluated. The QoS requirements required from the upper layers, where the file size, the TCP window size and the latency for efficient transmission are incorporated in the final formulation. Having obtained the formulation, simulation results highlight the impact of the QoS parameters to different TDD frame format, wherein the number of DL and UL subframes vary. Having taken into account this design aspects, we propose a framework for TDD frame adaptation within the LTE-A system. The aim of this framework is to provide the dynamic configuration of different TDD frame formats by calculating the DL:UL subframes ratio under certain channel conditions and QoS requirements. We also provide flowchart procedures of how such a solution could be implemented within the 3GPP LTE-A context. Simulation results are carried out, which reveal the probability of choosing the different TDD frame formats from the system under certain channel conditions and QoS requirements.

The Optimization of Combination Scheme in Cooperative Spectrum Sensing Based on the Practical Reporting Frame Format

In this paper, we investigated the important influence of reporting frame format in cooperative spectrum sensing (CSS), which was ignored in existing works. Firstly, we proposed a comparison between soft and hard combination schemes based on the practical reporting frame format. Furthermore, we derived the closed-form expression of optimal cooperative nodes in soft combination under the practical reporting condition. The theory analysis and simulation results show that the results of existing works would not hold when considering the real reporting frame format, and the optimal performance of CSS would be obtained when the sampling time equals to the reporting time.

The analysis of IEEE 802.11 PCF protocol based on LEO satellite Wi-Fi

In view of the problem of long propagation delay, hidden terminals and serious user conflicts in LEO satellite Wi-Fi scenario, this paper analysis the incompatibility of 802.11 DCF protocol briefly. A scheme of PCF polling mechanism based on priority is proposed and the frame format is adaptively modified. Through MATLAB simulation, the system throughput of the original scheme and the improvement scheme over the different transmission distance and nodes are analysed. The simulation results show that the improved PCF protocol can improve the throughput under the multi-user over long distances.

Mimic Encryption System for Network Security

With the rapid development of the Internet, increasingly more attention has been paid to network security problems. A network security defense technology has become a very important research field. Currently, most network equipment transmits data in plaintext at the data link layer, which exposes important information, such as IP addresses, port numbers, and application protocols, to an attacker and provides an opportunity for network attacks. To protect a network against attacks and ensure its security, this paper proposes a mimic encryption system for network security. Based on the concepts of moving target defense and mimic security defense, using the principles of randomization, dynamism, and diversification, a data link layer mimic encryption system is constructed from the underlying network of an information system. By transforming the frame format, a reconfigurable encryption algorithm, an hash algorithm, and a pseudo-random number generator are used to design different combination encryption modes. Then, the hash value of an encrypted frame is obtained by performing the hash operation, and feedback update is performed to generate new key parameters for the hash key pool. In addition, the pseudo-random selection of combinations of encryption algorithms and keys is performed to achieve “one frame-one key”. Finally, an FPGA is used as the network encryption card, and a CPU is used to realize two-party key agreement and the upper layer application. Using the FPGA + CPU hardware and software collaboration, the attack surface is expanded. Taking advantage of the high anti-interference property of an FPGA, part of the attack against the software system is filtered. The experimental results and analysis show that the encryption and decryption performance of this system in a 10 G network are approximately 500 MB/s. Thus, the system can effectively prevent the leakage of user data and resist network sniffing, vulnerability attacks, exhaustive key search attacks, and ciphertext-only attacks. Moreover, this system provides high security.

Fabrication of Bimetallic Au–Pd–Au Nanobricks as an Archetype of Robust Nanoplasmonic Sensors

Conventional gas sensors work upon changes in mechanical or conductive properties of sensing materials during a chemical process, which may limit availabilities of size miniaturization and design simplification. However, fabrication of miniaturized sensors with superior sensitivities in real-time and label-free probing of chemical reactions or catalytic processes remains highly challenging, in particular with regard to integration of materials into a desired smaller volume without losing the recyclability of sensing properties. Here, we demonstrate a unique bimetallic nanostructure, the Au–Pd–Au core–shell–frame nanobrick, as a promising archetype for fabrication of miniaturized sensors at nanoscale. Upon analysis of the aqueous synthesis, both ex situ and in situ, the formation of Au frames is consistent with selective deposition and aggregation of NaBH4-reduced Au nanoparticles at the corners and edges of cubic Pd shells, where the {100} surfaces, capped by iodide ions, are growth-limited. By virtue of ...

Trypanosomatid mitochondrial RNA editing: dramatically complex transcript repertoires revealed with a dedicated mapping tool.

RNA editing by targeted insertion and deletion of uridine is crucial to generate translatable mRNAs from the cryptogenes of the mitochondrial genome of kinetoplastids. This type of editing consists of a stepwise cascade of reactions generally proceeding from 3′ to 5′ on a transcript, resulting in a population of partially edited as well as pre-edited and completely edited molecules for each mitochondrial cryptogene of these protozoans. Often, the number of uridines inserted and deleted exceed the number of nucleotides that are genome-encoded. Thus, analysis of kinetoplastid mitochondrial transcriptomes has proven frustratingly complex. Here we present our analysis of Leptomonas pyrrhocoris mitochondrial cDNA deep sequencing reads using T-Aligner, our new tool which allows comprehensive characterization of RNA editing, not relying on targeted transcript amplification and on prior knowledge of final edited products. T-Aligner implements a pipeline of read mapping, visualization of all editing states and their coverage, and assembly of canonical and alternative translatable mRNAs. We also assess T-Aligner functionality on a more challenging deep sequencing read input from Trypanosoma cruzi. The analysis reveals that transcripts of cryptogenes of both species undergo very complex editing that includes the formation of alternative open reading frames and whole categories of truncated editing products.