FAULT LOCATION ESTIMATION FOR TWO-LINE FAULT INVOLVING DIFFERENT PHASES FROM EACH OF PARALLEL LINES

A novel numerical algorithm of fault location estimation for double line to ground fault involving different phases from each of two parallel lines is presented in this paper.It is based on the one terminal voltage and current data.The loop and nodal equations comparing faulted phase with non faulted phase of two parallel lines are introduced in the fault location estimation models,in which the source impedance of a remote end is not involved.The effects of load flow and fault resistance on the accuracy of fault location are effectively eliminated,therefore precise algorithms of locating fault are derived.The algorithm is demonstrated by digital computer simulations.

Solutions to Insecurity Problems in Seed Production of Two-line Hybrid Rice

The insecure problems of seed production have seriously hampered the healthy and sustainable development of two-line hybrid rice.The safety issues on seed production of two-line hybrid rice and current research situation were pointed out in this paper.The three main reasons for unsafety in seed production of twoline hybrid rice were unsuitable site selection,high critical sterility-inducing temperature and the drift of critical temperature.In this paper,strategies and measures were put forward based on many years of practice.It could minimize the risk in seed production of two-line hybrid rice by selecting dual-purpose genic male sterile line with lower critical sterility-inducing temperature and long lower temperature resistant time.Based on the climate data and climatic demands of the ＂three safe-periods＂ in seed production,a new idea for determining appropriate bases and periods for seed production was proposed by using computer technology,which solved the aimless selection of sites and periods for the seed production of two-line hybrid rice.Besides,we established a system of single plant selection and identification method and original seed propagation with cyclic cold water,which could reduce the generation number of original seed propagation in seed production and avoid the drift of critical sterility-inducing temperature.This paper improved the seed production safety in the three aspects of seed nature,seed source and seed production site.

Study on Mutagenic Effect of Space Flight in Two-line Sterile Rice

Seeds of two-line sterile rice cultivars Zhu 1S and Lu 18S were carried into space by ＂Shijian 8＂ breeding recoverable satellite, then planted in ground. Mutagenic effects from space induction were compared with those from y-irradiation and complex processing of space induction and y-irradiation. The results showed that agronomic effect was stimulated in Mo progenies of the two-line sterile rice varieties treated by space flight, and their radiosensitivities to the irradiation of space flight performed non-sensitive. The order of mutation frequency was determined to be SP ＋ γ 〉 γ 〉 SP in M2 generation. And a series of mutated elites（individuals） were screened. Physiological indices of mutants screened like the activity of protective enzymes were measured to explore the physiological and biochemical basis of biological effect in space environment to two-line sterile rice. The results of this study show that space mutation breeding is an effective novel mean for breeding.

Effects of Nitrogen Quantity on Grain-filling Characters of Two-line Hybrid Rice with Large Ear

[Objective] The aim was to research effects of N quantity on grain-filling characters of two-line hybrid rice cultivars with large ears. [Method] Peiza 67 and 88, two-line hybridized rice with large ears, were made use of to study on effects of N fertilizer in different quantities （LN： 90 kg/hm2;MN： 180 kg/hm2;HN： 270 kg/hm2） on plumpness and grain-filling characters. [Result] When N fertilizers were excessive, for inferior grains, grain-filling rate decreased and grain-filling time extended, resulting in plumpness decline after degradation of leaves＇ function. When N fertilizers were inadequate, maximal and average grain-filling rates decreased and the differences between superior and inferior grains in grain-filling rate increased, leading to decline of grain＇s weight and plumpness degree. On the other hand, quantity of N fertilizers had little effect on superior grains in plumpness. [Conclusion] The research provided references for reasonable use of N fertilizer and improvement of rice yield and N use.

Breeding of National Authorized Two-line Hybrid Rice Yanliangyou 2208

The breeding processes, characteristics and comprehensive characters of two-line hybrid rice Yanliangyou 2208 and its parents （Yan 220S and Yanhui 888） taking part in the national rice regional test of southern rice regions were introduced. Yanliangyou 2208 was approved by the National Crop Variety Appraisal Committee in 2013. The achievement has been transformed successfully and has been applied in production. It has good development and promotion prospects.

Construction of Accumulated Temperature Effect Model for Fertility Alteration of Two-line Sterile Line P88S

[Objective]The research aimed at constructing an accumulated temperature effect model for fertility alteration of two-line hybrid rice P88S.[Method]Analyze the experiment datas of fertility alteration of P88S in Hainan from 2005 to 2006.[Result]The fertilities of P88S with temperatures ranging from 26 to 28 ℃ were determined by the absolute values and the accumulation effects of the temperature.An accumulation effect model of temperatures based on the bistable state was obtained.[Conclusion]The temperature asymmetry of fertility alteration for two-line sterility line in spring and autumn can be elucidated effectively using the accumulated temperature effect model,namely,alternating from fertile to sterile requires higher temperatures,and alternating from sterile to fertile requires lower temperatures.

Thoughts and Practice on Some Problems about Research and Application of Two-Line Hybrid Rice

The main problems about research and application of two-line hybrid rice were reviewed, including the confusing nomenclature and male sterile lines classification, the unclear characteristics of photoperiod and temperature responses and the unsuitable site selection for male sterile line and hybrid dce seed production. In order to efficiently and accurately use dual-purpose genic male sterile lines, four types, including PTGMS （photo-thermo-sensitive genic male sterile rice）, TGMS （thermo-sensitive genic male sterile rice）, reverse PTGMS and reverse TGMS, were proposed. A new idea for explaining the mechanism of sterility in dual-purpose hybrid rice was proposed. The transition from sterile to fertile was involved in the cooperative regulation of major-effect sterile genes and photoperiod and/or temperature sensitive ones. The minor-effect genes with accumulative effect on sterility were important factors that affected the critical temperature of sterility transfer. In order to make better use of dual-purpose lines, the characterization of responses to photoperiod and temperature of PTGMS should be made and the identification method for the characterization of photoperiod and temperature responses of PTGMS should also be put forward. The optimal ecological site for seed production could be determined according to the historical climate data and the requirements for the meteorological conditions during the different periods of seed production.

Research on Theories and Techniques of Irrigation for Safeguarding Seed Production of Two-Line Hybrid Rice

By inducing frequency, intensity and duration of lower temperature in the middle and last ten-day periods in August in the rice-growing areas of southern China, increasing temperature for safe seed production was defined as 2℃. During the sensitive period of fertility, characters of panicle height and canopy structure of TGMS rice, Pei＇ai64S, were measured. Results showed that temperature changes caused by irrigation in fields were below 40 cm of rice plant, and heating effect was significant at 20 cm when the temperature was increased by 3.1 ℃. For the present study, the following irrigation techniques were put forth： the water depth of 15-20 cm, current water used, irrigating after 17：00 and bailing at 10：00 in sunny or cloudy weather, irrigating on whole day, in shady or rainy weather, increasing inflows and outflows in large fields. In the present experiment, pollen fertility and self-fertilized seed setting rate accepted that the techniques were feasible and effective for against lower temperature and safeguarding seed production of two-line hybrid rice.

Causes of Poor Grain Plumpness of Two-Line Hybrids and Their Relationships to the Contents of Hormones in the Rice Grain

This study was designed to elucidate the grain filling characteristics and the causes of poor grain plumpness of some two-line hybrid rice combinations and their hormonal mechanism. Six varieties, including three two-line hybrid rice combinations, that show differences in seed-setting and grain filling, were used. And the contents of starch, sucrose, zeatin （Z） ＋ zeatin riboside （ZR）, indole-3-acetic acid （IAA）, and abscisic acid （ABA）, the ethylene evolution rate, activities of sucrose synthase （SuSase） and starch synthase （StSase） in grains, the seed-setting and grain filling rate were investigated. The correlations amongst these were analyzed. The results showed that the poor grain filling of two-line hybrids was mainly attributed to the higher unfilled grain rate and the lower filling degree of inferior grains. During the early and mid grain filling periods, the sucrose content in inferior grains was greater than that in superior grains for the combinations with poor grain filling, indicating that the substrate concentration was not the principal factor for their slow grain filling and poor grain plumpness of the inferior grains of two-line hybrids. Z ＋ ZR, IAA, and ABA in superior grains were obviously greater than those in inferior grains at early grain filling stage. The maximum and mean contents of Z ＋ ZR, IAA, and ABA were positively very significantly correlated with the maximum and mean grain-filling rate, filling degree, and grain weight. The evolution rate of ethylene was greater in inferior grains than in superior grains and greater for the combinations with poor grain plumpness than those with good grain plumpness at the early or mid filling stages. The evolution rate of ethylene was negatively and significantly correlated with the grain filling rate, the grain filling degree, and the grain weight. Spraying ethephon （ethylene-releasing agent） at the early grain filling stage increased the evolution rate of ethylene, reduced the ABA content and activities of SuSase and StSase, and decreased the grain filling degree and the grain weight. The results were reversed when cobatous nitrate （an inhibitor of ethylene synthesis） was applied. The results suggested that the hormones and their balance play a role in the regulation of grain filling and enzymatic activities, and the poor grain filling is attributed to the low contents of Z ＋ ZR, IAA, and ABA, and the high evolution rate of ethylene in the inferior grains of some two-line hybrid rice combinations. The results suggested that hormones play important roles in the grain filling of some two-line hybrid rice combinations, and their filling degree can be improved by regulating the hormonal contents.

Inheritance Pattern of Two-line Hybrid Rice Resistance to False Smut

[Objective] The aim of this study was to explore the inheritance pattern of the resistance of two-line hybrid rice to false smut. [Method] A moderate susceptible TGMS line 33S as the female parent, was crossed with 30 susceptible restorer lines and 23 resistant restorer lines. Then false smut resistance of the hybrid F1 and parents were identified. [Result] All F1 of 33S crossed with 30 susceptible re- storer lines were susceptible to rice false smut. The F1 of 33S crossed with 23 re- sistant restorer lines showed dominant, incompletely dominant or recessive inheri- tance. Dominant and incompletely dominant inheritance accounted for 87.0%. The diseased panicle rate, disease index, average diseased grains per panicle, and the highest diseased grains per panicle of F1 shared highly significant positive correla- tions with corresponding indicators of restorer lines. [Conclusion] This study provides references for genetic improvement of two-line hybrid rice.

Analysis on Genetic Differences between Parents of Two-line Medium Indica Hybrid Rice by SSR Markers

The genetic diversity of 50 parents or improved lines of two-line medium Indica hybrid rice were analyzed based on 48 pairs of SSR markers. The results showed that the clustering results were highly accordant with the parental pedigree information of the tested materials. The male sterile lines and the restoring lines were clustered into 2 distinct groups （Ⅰ and Ⅱ）, respectively. There were no significant difference in intra-group average genetic distances （GD） between the 2 groups. Most of the male sterile lines from Hunan Longping High-tech Seed Science Research Institute Co., Ltd. were grouped into a single subgroup （Ⅰ-4） under the male sterile group with the largest average GD compared with the rest male sterile subgroups. Huazhan derived lines and Guangzhou inbred lines were founded to be independent of 9311 and its derivatives or closely-related lines. Meanwhile, they have obviously been differentiated into 2 subgroups （Ⅱ-2 and Ⅱ-3）. The lines derived from Huazhan （or genetic closely related lines） showed a genetic homogenization phenomenon. Therefore, the Huazhan-derived lines should be further improved by the utilization of germplasms with good quality, high resistance and wide adaptability from Southern China to widen the GD between Huazhan derived lines and the male sterile subgroup developed by Hunan Longping High-tech Seed Science Research Institute Co., Ltd., so as to further promote the heterosis level between the groups.

Semi-Markovian Model of Two-Line Queuing System with Losses

In the present paper, to build model of two-line queuing system with losses GI/G/2/0, the approach introduced by V.S. Korolyuk and A.F. Turbin, is used. It is based on application of the theory of semi-Markov processes with arbitrary phase space of states. This approach allows us to omit some restrictions. The stationary characteristics of the system have been defined, assuming that the incoming flow of requests and their service times have distributions of general form. The particular cases of the system were considered. The used approach can be useful for modeling systems of various purposes.

Breeding of a Water-saving Drought-resistant Two-line Hybrid Rice Variety Wanliangyou 1008

Drought is one of the important factors limiting rice production,and the application of new water-saving rice varieties is urgently needed in rice production.Wanliangyou 1008 bred by Institute of Rice Research,Anhui Academy of Agricultural Sciences is a new two line hybrid rice variety with some good traits,including high drought resistance,high yield and good disease resistance.Wanlingyou 1008 was obtained by crossing drought-resistant high-quality restorer line DJ1008 and disease-resistant two-line sterile line Wan 25S.In this paper,the breeding process,characteristics and seed production technology of the variety were described in detail.

Performance and High-Yield Cultural Techniques of Two-Line Hybrid Rice Xinlingyou998 at Direct Seeding Cultivation

Xinliangyou 998 is a new indica two-line hybrid rice variety using Xin＇er Sx H0998 as parent. The variety was introduced and demonstrated in Yingshan County in 2016, and showed intermediate growth duration, strong tillering ability, firm culm, tolerance to high fertility and resistance to lodging, tolerance to high tempera- ture and wide range of adaptation, etc. The high-yield cultural techniques were con- cluded.

An MPI parallel DEM-IMB-LBM framework for simulating fluid-solid interaction problems

The high-resolution DEM-IMB-LBM model can accurately describe pore-scale fluid-solid interactions,but its potential for use in geotechnical engineering analysis has not been fully unleashed due to its prohibitive computational costs.To overcome this limitation,a message passing interface(MPI)parallel DEM-IMB-LBM framework is proposed aimed at enhancing computation efficiency.This framework utilises a static domain decomposition scheme,with the entire computation domain being decomposed into multiple subdomains according to predefined processors.A detailed parallel strategy is employed for both contact detection and hydrodynamic force calculation.In particular,a particle ID re-numbering scheme is proposed to handle particle transitions across sub-domain interfaces.Two benchmarks are conducted to validate the accuracy and overall performance of the proposed framework.Subsequently,the framework is applied to simulate scenarios involving multi-particle sedimentation and submarine landslides.The numerical examples effectively demonstrate the robustness and applicability of the MPI parallel DEM-IMB-LBM framework.

Parallel Implementation of the CCSDS Turbo Decoder on GPU

This paper presents a software turbo decoder on graphics processing units(GPU).Unlike previous works,the proposed decoding architecture for turbo codes mainly focuses on the Consultative Committee for Space Data Systems(CCSDS)standard.However,the information frame lengths of the CCSDS turbo codes are not suitable for flexible sub-frame parallelism design.To mitigate this issue,we propose a padding method that inserts several bits before the information frame header.To obtain low-latency performance and high resource utilization,two-level intra-frame parallelisms and an efficient data structure are considered.The presented Max-Log-Map decoder can be adopted to decode the Long Term Evolution(LTE)turbo codes with only small modifications.The proposed CCSDS turbo decoder at 10 iterations on NVIDIA RTX3070 achieves about 150 Mbps and 50Mbps throughputs for the code rates 1/6 and 1/2,respectively.

Evaluation on Configuration Stiffness of Overconstrained 2R1T Parallel Mechanisms

Currently,two rotations and one translation(2R1T)three-degree-of-freedom(DOF)parallel mechanisms(PMs)are widely applied in five-DOF hybrid machining robots.However,there is a lack of an effective method to evaluate the configuration stiffness of mechanisms during the mechanism design stage.It is a challenge to select appropriate 2R1T PMs with excellent stiffness performance during the design stage.Considering the operational status of 2R1T PMs,the bending and torsional stiffness are considered as indices to evaluate PMs'configuration stiffness.Subsequently,a specific method is proposed to calculate these stiffness indices.Initially,the various types of structural and driving stiffness for each branch are assessed and their specific values defined.Subsequently,a rigid-flexible coupled force model for the over-constrained 2R1T PM is established,and the proposed evaluation method is used to analyze the configuration stiffness of the five 2R1T PMs in the entire workspace.Finally,the driving force and constraint force of each branch in the whole working space are calculated to further elucidate the stiffness evaluating results by using the proposed method above.The obtained results demonstrate that the bending and torsional stiffness of the 2RPU/UPR/RPR mechanism along the x and y-directions are larger than the other four mechanisms.

Configuration and Kinematics of a 3-DOF Generalized Spherical Parallel Mechanism for Ankle Rehabilitation

The kinematic equivalent model of an existing ankle-rehabilitation robot is inconsistent with the anatomical structure of the human ankle,which influences the rehabilitation effect.Therefore,this study equates the human ankle to the UR model and proposes a novel three degrees of freedom(3-DOF)generalized spherical parallel mechanism for ankle rehabilitation.The parallel mechanism has two spherical centers corresponding to the rotation centers of tibiotalar and subtalar joints.Using screw theory,the mobility of the parallel mechanism,which meets the requirements of the human ankle,is analyzed.The inverse kinematics are presented,and singularities are identified based on the Jacobian matrix.The workspaces of the parallel mechanism are obtained through the search method and compared with the motion range of the human ankle,which shows that the parallel mechanism can meet the motion demand of ankle rehabilitation.Additionally,based on the motion-force transmissibility,the performance atlases are plotted in the parameter optimal design space,and the optimum parameter is obtained according to the demands of practical applications.The results show that the parallel mechanism can meet the motion requirements of ankle rehabilitation and has excellent kinematic performance in its rehabilitation range,which provides a theoretical basis for the prototype design and experimental verification.

An efficient parallel algorithm of variational nodal method for heterogeneous neutron transport problems

The heterogeneous variational nodal method(HVNM)has emerged as a potential approach for solving high-fidelity neutron transport problems.However,achieving accurate results with HVNM in large-scale problems using high-fidelity models has been challenging due to the prohibitive computational costs.This paper presents an efficient parallel algorithm tailored for HVNM based on the Message Passing Interface standard.The algorithm evenly distributes the response matrix sets among processors during the matrix formation process,thus enabling independent construction without communication.Once the formation tasks are completed,a collective operation merges and shares the matrix sets among the processors.For the solution process,the problem domain is decomposed into subdomains assigned to specific processors,and the red-black Gauss-Seidel iteration is employed within each subdomain to solve the response matrix equation.Point-to-point communication is conducted between adjacent subdomains to exchange data along the boundaries.The accuracy and efficiency of the parallel algorithm are verified using the KAIST and JRR-3 test cases.Numerical results obtained with multiple processors agree well with those obtained from Monte Carlo calculations.The parallelization of HVNM results in eigenvalue errors of 31 pcm/-90 pcm and fission rate RMS errors of 1.22%/0.66%,respectively,for the 3D KAIST problem and the 3D JRR-3 problem.In addition,the parallel algorithm significantly reduces computation time,with an efficiency of 68.51% using 36 processors in the KAIST problem and 77.14% using 144 processors in the JRR-3 problem.

Performance Enhancement of XML Parsing Using Regression and Parallelism

The Extensible Markup Language(XML)files,widely used for storing and exchanging information on the web require efficient parsing mechanisms to improve the performance of the applications.With the existing Document Object Model(DOM)based parsing,the performance degrades due to sequential processing and large memory requirements,thereby requiring an efficient XML parser to mitigate these issues.In this paper,we propose a Parallel XML Tree Generator(PXTG)algorithm for accelerating the parsing of XML files and a Regression-based XML Parsing Framework(RXPF)that analyzes and predicts performance through profiling,regression,and code generation for efficient parsing.The PXTG algorithm is based on dividing the XML file into n parts and producing n trees in parallel.The profiling phase of the RXPF framework produces a dataset by measuring the performance of various parsing models including StAX,SAX,DOM,JDOM,and PXTG on different cores by using multiple file sizes.The regression phase produces the prediction model,based on which the final code for efficient parsing of XML files is produced through the code generation phase.The RXPF framework has shown a significant improvement in performance varying from 9.54%to 32.34%over other existing models used for parsing XML files.