小龙虾识别与度量关键技术研究与应用

小龙虾的表型性状是水产养殖和遗传育种中非常重要的经济依据,为了精准实现对小龙虾的视觉检测与定位,并对其主体躯干表型特征进行测量。首先提出了一种基于Mask RCNN实例分割模型检测小龙虾的方法,不仅能快速识别小龙虾,还能对其进行实例分割,生成高质量的二值掩膜图。然后在此基础上,提出一种新的小龙虾度量算法:通过提取小龙虾的轮廓曲线,获取其中轴线,采用分区法提取小龙虾的特征区域,再利用凸包和凸包缺陷算法获取小龙虾的特征点,实现对其全长、体长、头胸甲、腹部、尾扇等主要部位的无接触度量计算。结果表明:Mask RCNN模型在小龙虾数据集上具有很好的泛化性能,模型分割准确率达到了94.6%,目标识别的平均检测精度达到了98.7%。各测量指标的平均绝对误差均在5 mm之内,比人工手动测量难度大大减小,并且稳定高效,重复性更好。该方法将有利于生产和选育过程中小龙虾的鉴别及结构尺寸的快速获取。

一种合并状态度量计算的高效并行Turbo码译码器结构设计及FPGA实现

为满足无线通信中高吞吐、低功耗的要求,并行译码器的结构设计得到了广泛的关注。基于并行Turbo码译码算法,研究了前后向度量计算中的对称性,提出了一种基于前后向合并计算的高效并行Turbo码译码器结构设计方案,并进行现场可编程门阵列(field-programmable gate array,FPGA)实现。结果表明,与已有的并行Turbo码译码器结构相比,本文提出的设计结构使状态度量计算模块的逻辑资源降低50%左右,动态功耗在125 MHz频率下降低5.26%,同时译码性能与并行算法的译码性能接近。

计算机系统变革性研究的4个问题

进入21世纪,计算机科学与技术领域正在面临一次深刻的变革,计算机系统子领域也不例外.指出这次变革的一个主要特征是从"人机共生"跃变到"人机物社会".这个跃变也为计算机系统的研究提出了4个带有基础性的挑战:1)重新审视计算和计算机系统概念,以及刻画新型负载和使用模式;2)研究新型的计算机系统度量;3)让计算机系统直接支持网络;4)发现和利用涌现现象.基于中国科学院计算技术研究所织女星网格小组和国际同行的研究工作,讨论了这4个问题,并指出这些问题还没有答案,这提供了很多研究机会.

基于EMD的剖分空间关系计算模型初探

针对在空间关系计算中存在的经纬度坐标缺少区域信息的问题,以及基于影像直接进行空间关系计算中存在的计算复杂的问题,利用具有点面二相性的基于地图分幅的扩展模型(EMD)全球剖分面片作为空间关系计算的基本单位,采用EMD全球剖分面片编码代替经纬度坐标进行空间关系计算,提出EMD剖分空间关系计算模型的体系架构,并在此基础上进行验证实验,证实了该模型的可行性。

基于复杂网络的软件复杂性度量的研究

随着计算机科学技术的不断发展,软件的规模性和复杂性不断的扩大,随之带来的问题是传统的度量方法和对软件的开发控制不能满足日益发展的计算机科学技术的发展。在这个问题上,我国的研发人员付出了很大的努力,去发现新的方法对软件测量的使用,从而控制软件的质量,优化软件的结构,使软件的开发有利于计算机科学技术的发展。

通信行业标准中软件运维非功能性工作量评估方法研究

本文对信息化项目中软件开发投入运营后运维部分的投资估算标准方法的相关研究。通过研究现有信息化项目涉及的国家标准、地方标准、团体标准等标准,结合软件开发需求单位、用户维度痛点以及分析实际软件开发运维工作涉及的系统、运维工作内容等相关数据,提出相应的估算标准方法。为信息化项目软件运维非功能性相关工作量的投资估算提供较为清晰、准确的方法。

CMDC:一种差异互补的迭代式多维度文本聚类算法

针对传统多维度文本聚类算法把文本表示与聚类过程分离,忽略了维度间的互补特性的问题,提出了一种差异互补的迭代式多维度文本聚类算法——CMDC,实现文本聚类与特征调整过程的统一优化。CMDC算法挑选维度聚类间结果的互补文本,基于局部度量学习算法利用互补文本促进聚类的特征调优,以维度的度量一致性来解决多维度文本聚类的划分一致性。实验结果表明,CMDC算法有效地提升了多维度聚类性能。

Theoretical Calculation of Nitrogen Q-Branch CARS Spectra

The coherent anti Stokes Raman spectrum (CARS) technology, as a new temperature measurement method, is paid more and more attention to recently. The theoretical CARS spectra of nitrogen Q branch are calculated, the spectra at different temperatures are obtained and the effect on the CARS spectra of Raman line width is also discussed. The results show that CARS spectra are sensitive to temperature and spectrum solution is good when the Raman line width is narrow enough. The accuracy of detonation temperature measurement with this technology will reach high level.

Modeling and performance evaluation of QoS-aware job scheduling of computational grids

To achieve high quality of service （QoS） on computational grids, the QoS-aware job scheduling is investigated for a hierarchical decentralized grid architecture that consists of multilevel schedulers. An integrated QoS-aware job dispatching policy is proposed, which correlates priorities of incoming jobs used for job selecting at the local scheduler of the grid node with the job dispatching policies at the global scheduler for computational grids. The stochastic high-level Petri net （SHLPN） model of a two-level hierarchy computational grid architecture is presented, and a model refinement is made to reduce the complexity of the model solution. A performance analysis technique based on the SHLPN is proposed to investigate the QoS-aware job scheduling policy. Numerical results show that the QoS-aware job dispatching policy outperforms the QoS-unaware job dispatching policy in balancing the high-priority jobs, and thus enables priority-based QoS.

The Calculations of Propeller Induced Velocity by RANS and Momentum Theory

In order to provide instructions for the calculation of the propeller induced velocity in the study of the hull-propeller interaction using the body force approach,three methods were used to calculate the propeller induced velocity：1） Reynolds-Averaged Navier-Stokes（RANS） simulation of the self-propulsion test,2） RANS simulation of the propeller open water test,and 3） momentum theory of the propeller.The results from the first two methods were validated against experimental data to assess the accuracy of the computed flow field.The thrust identity method was adopted to obtain the advance velocity,which was then used to derive the propeller induced velocity from the total velocity field.The results computed by the first two approaches were close,while those from the momentum theory were significantly overestimated.The presented results could prove to be useful for further calculations of self-propulsion using the body force approach.

Similarity measure design and similarity computation for discrete fuzzy data

The similarity computations for fuzzy membership function pairs were carried out.Fuzzy number related knowledge was introduced,and conventional similarity was compared with distance based similarity measure.The usefulness of the proposed similarity measure was verified.The results show that the proposed similarity measure could be applied to ordinary fuzzy membership functions,though it was not easy to design.Through conventional results on the calculation of similarity for fuzzy membership pair,fuzzy membership-crisp pair and crisp-crisp pair were carried out.The proposed distance based similarity measure represented rational performance with the heuristic point of view.Furthermore,troublesome in fuzzy number based similarity measure for abnormal universe of discourse case was discussed.Finally,the similarity measure computation for various membership function pairs was discussed with other conventional results.

High Accuracy Calculation for Excited-State Energies of H Atoms in a Magnetic Field

Using the recently developed finite-basis-set method with B splines, excited states of H atoms in a magnetic field have been calculated. Energy levels are presented for the ten excited states, 2so, 3d＇0, 3po, 3p-1, 3d_1, 4d-1, 3d-2, 4d-2, 4f-2 , and 5f-2 as a function of magnetic field strengths with a range from zero up to 2.35 × 10^6 T. The obtained results are compared with available high accuracy theoretical data reported in the literature and found to be in excellent agreement. The comparison also shows that the current method can produce energy levels with an accuracy higher than the existing high accuracy method [Phys. Rev. A 54 （1996） 287]. Here high accuracy energy levels are for the first time reported for the 3d＇0, 4d-1, 4d-2, 4f-2, and 5f-2 states.

Practical network coding-aware routing protocol for multi-hop wireless networks

Network coding has been considered as one of the effective strategies that improve the throughput of multi- hop wireless networks. In order to effectively apply network coding techniques to the real multi-hop wireless networks, a practical network coding aware routing protocol is proposed in this paper, for unicast sessions in multi- hop wireless networks. The protocol is based on a novel routing metric design that captures the characteristics of network coding and unicast sessions. To ensure the novel routing mettle can operate with practical and widely available path calculation algorithms, a unique mapping process is used to map a real wireless network to a virtual network. The mapping process ensures that the paths with the biggest coding opportunities will be selected by commonly used path calculation algorithms. Simulation results show that the proposed routing protocol is effective to improve the network throughput.

Calculation Model of Equivalent Strength for Induced Crack Based on Double-K Fracture Theory and Its Optimizing Setting in RCC Arch Dam

By means of fracture testing on roller-compacted concrete （RCC） three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture theory, KiniⅠC,KunⅠC, as well as the critical effective crack length and the critical crack tip opening displacement, were evaluated. Based on the double-K fracture parameters above, the calculation model of equivalent strength for induced crack was established, thus the calculation method on its initiation, stable propagation and unstable fracture was ascertained. Moreover, the finite element simulation analysis of stress field in ShaPai arch dam and the on-site observational splaying points of induced crack at different altitudes validated the reliability of the model. Finally, crack inducer′s optimal setting in RCC arch dam was studied. It improves the design level of induced crack in RCC arch dam and satisfies the necessity of engineering practice.

A New Calculation of the In-Medium Quark Condensate at Finite Density and Temperature

The in-medium quark condensate is studied with an equivalent-mass approach in which one does not need to make assumptions on the derivatives of model parameters with respect to the quark current mass.It is shown that the condensate is generally a decreasing function of both the density and temperature with the decreasing speed depending on the confinement parameter.Specially,at given density,the condensate decreases on increasing temperature.The decreasing speed is comparatively small at lower temperature,and becomes very fast at higher temperature.

Circular Rydberg States of Atomic Hydrogen in an Arbitrary Magnetic Field

We report a theoretical scheme using a B-spline basis set to improve the poor computational accuracy of circular Rydberg states of hydrogen atoms in the intermediate magnetic field. This scheme can produce high accuracy energy levels and valid for an arbitrary magnetic field. Energy levels of hydrogen are presented for circular Rydberg states with azimuthal quantum numbers ｜m｜ =10-70 as a function of magnetic field strengths ranging from zero to 2.35 × 10^9 T. The variation of spatial distributions of electron probability densities with magnetic field strengths is discussed and competition between Coulomb and magnetic interactions is illustrated.

The Degree of Association between Concepts Focusing on the Viewpoint

For a computer to perform intelligent information processing requires functions that can extract concepts from words, as humans do, and then associate those concepts with related concepts. In order to implement this association function, it is necessary to quantify the degree of association between two concepts. In the present paper, we propose a method for quantifying degree of association focusing on the viewpoint that uses a concept base （a knowledge base that expresses concepts as a collection of pairs, each pair consisting of an attribute word used to describe the concept and a weighting that expresses the word＇s importance）. Here, ＂Viewpoint＂ is the perspective from which a concept is viewed; for example, consider the degree of association between ＂airplane＂ and ＂automobile＂, and the degree of association between ＂airplane＂ and ＂bird＂. From the viewpoint of ＂vehicle＂, ＂airplane＂ and ＂automobile＂ are highly related, while from the viewpoint of ＂flight＂, ＂airplane＂ and ＂bird＂ are highly related. We present herein a comparison of two methods for calculating degree of association focusing on the viewpoint, and demonstrate that the method involving modulation of attribute weightings based on viewpoint results in degree of association calculations that are closer to human senses.

Evaluation of photon beam dose calculation accuracy of treatment planning systems using in vivo dosimetry

Objective The treatment planning system currently represents one of the basics of radiation therapy,because it is the only method to estimate patient dose delivery fast forward and accurately represent estimated tumor location of the tumor with the possibility of estimating densities in the tissue surrounding the tumor to overcome dose calculation defects but radial estimated the patient.Despite the flaws associated with the systems and calculates the dose of your programs in all programs currently existing in the world.Than necessary,to the existence of a review of the accuracy of accounts and how to confirm the radiation dose to the patient programs.Methods A total of 35 cancer patients were considered for this study,with 245 field measurements made with low-and high-energy diode detectors for brain and prostate cases.The treatments for all patients were planned using Eclipse Treatment Planning System version 13.6.Results Of the 105 field measurements made for the prostate cancer patients,16 included discrepancies outside the ±5% action level.Of the 145 measurements taken of the brain cases,there were four outside the ±5% action level.The results indicated a higher degree of accuracy.The study revealed that,for the prostate measurements,the higher discrepancy in the doses for the particular fields(exceeding the action level) may have been due to the isocenter being very close to the jaws and multi-leaf collimator of the linear accelerator machine.As a result,scatter from the jaws and the multi-leaf collimator could have contributed to the high dose delivered to the diode;hence,a probable higher discrepancy of the dose in more brain cases due highest quality of VMAT technique and fixation system.Conclusion A greater percentage of the observed discrepancies were well within the set tolerance level.However,it is recommended that the positioning of the diode on the patient's skin and the angular sensitivity of the diodes be reconsidered.It is also recommended that a more accurate calculation of expected diode values be performed,especially for fields that pass through the table.These efforts would achieve action levels of ±5%.

Characteristics of water exchange in the Luzon Strait during September 2006

The Luzon Strait is the only deep channel that connects the South China Sea(SCS) with the Pacific.The transport through the Luzon Strait is an important process influencing the circulation,heat and water budgets of the SCS.Early observations have suggested that water enters the SCS in winter but water inflow or outflow in summer is quite controversial.On the basis of hydrographic measurements from CTD along 120° E in the Luzon Strait during the period from September 18 to 20 in 2006,the characteristics of temperature,salinity and density distributions are analyzed.The velocity and volume transport through the Luzon Strait are calculated using the method of dynamic calculation.The major observed results show that water exchanges are mainly from the Pacific to the South China Sea in the upper layer,and the flow is relatively weak and eastward in the deeper layer.The net volume transport of the Luzon Strait during the observation period is westward,amounts to about 3.25 Sv.This result is consistent with historical observations.