基于功率谱流形的信息几何DP-TBD算法

针对复杂杂波背景下目标信杂比起伏而导致的漏检问题,本文结合信息几何检测器的性能优势与动态规划检测前跟踪(Dynamic Programming Track Before Detect,DP-TBD)的多帧信息积累能力,提出了基于功率谱流形的信息几何DP-TBD算法.该算法利用功率谱流形与矩阵流形对偶关系,设计了功率谱信息几何检测器,将信息几何检测器的计算复杂度降低了近两个数量级.通过实测数据实验验证,功率谱DP-TBD算法可实现与矩阵DP-TBD算法相近的检测性能,并将运算时间降低为矩阵DP-TBD算法的3%~8%.此外,相较于信息几何检测器,功率谱DP-TBD可将检测信杂比(Signal-to-Clutter Ratio,SCR)提高2~3 dB.

基于多层次客流需求的高铁列车谱系结构优化设计

高速铁路的高质量服务特性激发了大量不同类型旅客的多样化出行需求。当前铁路旅客列车开行数量日益增多,但提供的客运产品分类较少,列车谱系化特征不明显,难以适应旅客的多样性需求。设计具有显性差异特征的铁路客运产品,满足不同类型旅客在经济、快捷、方便、舒适等方面的异质性出行需求,实现铁路客流分类与产品分类的高效匹配,对新时代铁路旅客运输发展具有重要意义。结合当前我国高速铁路网列车开行结构现状,并考虑路网中各线路具有不同的资源、能力、客流特征,基于铁路客运产品谱系化思想和发展趋势,从列车停站模式、旅速、运距、频率几个维度将既有列车种类进一步拓展划分为11类谱系,分析多层次旅客对谱系列车的选择,运用整数规划并结合客流分配技术,构建决策各线路区段上从11类谱系中选择列车开行种类、范围和数量的列车谱系结构优化模型,达到客流类型与列车谱系结构之间的有效匹配。以我国部分高铁路网为例开展案例研究,研究结果表明:优化后的列车开行结构明显改善,各高铁线路上列车谱系结构差异化分布特征明显;不同层次客流旅速、列车谱系和客流层次对应、列车客座率、“车-流”运距比等指标均表现出较好的“车-流”匹配效果。在高铁列车大规模成网运营条件下,研究结果可为设计具有谱系特征的列车产品提供方法和技术指导。

基于图可解释网络的软件错误定位

软件错误定位技术旨在通过挖掘程序与测试用例执行数据,提升定位准确性;针对SBFL技术过于依赖二进制覆盖信息的问题,提出一种基于图可解释网络的软件错误定位方法,将测试执行转化为图结构,利用图注意网络建模深度挖掘代码片段隐含的信息及其相互关系,并采用强化学习思想对图注意力网络学习后的决策过程进行解释,从而确定关键节点,缩小错误定位范围;实验的场景设立在Defects4j数据集的5个项目进行,并与SBFL及未经过解释的深度学习方法进行了对比;结果显示,基于图可解释网络的定位方法在Top-1、Top-3和Top-5指标上分别提升了7.26%、7.56%和9.96%,EXAM指数也提升了8.98%,显著优于其他方法。

Evaluation of Clinician Training in Autism Screening, Care Management, and Patient Education

Objective: The demand for pediatric developmental evaluations has far exceeded the workforce available to perform them, which creates long significant wait times for services. A year-long clinician training using the Extension for Community Healthcare Outcomes (ECHO®) model with monthly meetings was conducted and evaluated for its impact on primary care clinicians’ self-reported self-efficacy, ability to administer autism screening and counsel families, professional fulfillment, and burnout. Methods: Participants represented six community health centers and a hospital-based practice. Data collection was informed by participant feedback and the Normalization Process Theory via online surveys and focus groups/interviews. Twelve virtual monthly trainings were delivered between November 2020 and October 2021. Results: 30 clinicians participated in data collection. Matched analyses (n = 9) indicated statistically significant increase in self-rated ability to counsel families about autism (Pre-test Mean = 3.00, Post-test Mean = 3.89, p = 0.0313), manage autistic patients’ care (Pre-test Mean = 2.56, Post-test Mean = 4.11, p = 0.0078), empathy toward patients (Pre-test Mean = 2.11, Post-test Mean = 1.22, p = 0.0156) and colleagues (Pre-test Mean = 2.33, Post-test Mean = 1.22, respectively, p = 0.0391). Unmatched analysis revealed increases in participants confident about educating patients about autism (70.59%, post-test n = 12 vs. 3.33%, pre-test n = 1, p = 0.0019). Focus groups found increased confidence in using the term “autism”. Conclusion: Participants reported increases in ability and confidence to care for autistic patients, as well as empathy toward patients and colleagues. Future research should explore long-term outcomes in participants’ knowledge retention, confidence in practice, and improvements to autism evaluations and care.

不同运动项目对孤独症谱系障碍儿童干预效果的探讨

孤独症谱系障碍作为一种神经发育障碍疾病,其严重威胁到儿童的日常生活和身心健康,是每个家庭的沉重负担。目前,孤独症谱系障碍儿童发病率也呈上升趋势,其具体发病机制尚未完全清楚,有许多以运动干预为手段的治疗方法,其对孤独症谱系障碍儿童有效,但是仍存在运动方案不完整。本文针对不同运动项目对孤独症谱系障碍儿童的干预效果进行综述,以期为孤独症儿童的运动干预提供指导和借鉴。

Energy-Efficient Target Channel Sequence Design for Spectrum Handoffs in Cognitive Radio Networks

Cognitive radio is considered as an efficient way to improve the spectrum efficiency. As one of its key technologies,spectrum handoff can guarantee the transmission continuity of secondary users(SUs). In this paper,we address a new and more generalized spectrum handoff problem in cognitive radio networks(CRNs),by considering simultaneously energy efficiency,multiple spectrum handoffs and multiple channels. Furthermore,effects of the primary users'(PUs')arrival and service rate on the target channel sequence selection are also considered. In order to obtain the energy-efficient target channel sequence,we firstly analyze the energy consumption and the number of delivered bits per hertz in the spectrum handoff process,and formulate a ratio-type energy efficiency optimization problem,which can be transformed into a parametric problem by utilizing fractional programming. Then,we propose an algorithm combining dynamic programming with bisection(DPB)algorithm to solve the energy efficiency optimization problem. Our simulation results verify that the designed target channel sequence has better performance than the existing algorithms in terms of energy efficiency.

Dynamic Promotional Resource Allocation for Segment Specific and Spectrum Effect of Promotion for a Product Line Incorporating Repeat Purchase Behavior

Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant and lack substantial growth because the brands would have low visibility in the market. Moreover, today’s vast and assorted markets comprise of customers with different needs and varied behavior. So it is rarely possible for companies to satisfy all customers by treating them alike. Thus there arises a need to divide the market into segments having customers with similar traits/characteristics. After identifying appropriate market segments, firms can design differentiated promotional campaigns for each segment. At the same time there can be a mass market promotional campaign that reaches different segments with a fixed spectrum. Also since promotional effort resources are limited, one must use them judiciously. In this paper, we formulate mathematical programming problem under repeat purchase scenario, which optimally allocates mass promotional effort resources and differentiated promotional effort resources across the segments dynamically in order to maximize the overall sales obtained from multiple products of a product line under budgetary and minimum sales aspiration level constraint on each product under consideration in each segment. The planning horizon is divided into multi periods, the adoption pattern of each product in each segment is observed in every subinterval and accordingly promotional effort allocations are determined for the next period till we reach the end of planning period. The optimization model has been further extended to incorporate minimum aspiration level constraints on total sales for each product under consideration from all the segments taken together. The non linear programming problem so formulated is solved using differential evolution approach. A numerical example has been discussed to illustrate applicability of the model.

Spectrum Allocation for Cognitive Radio Networks with Non-Deterministic Bandwidth of Spectrum Hole

The spectrum allocation for cognitive radio networks(CRNs) has received considerable studies under the assumption that the bandwidth of spectrum holes is static. However, in practice, the bandwidth of spectrum holes is time-varied due to primary user/secondary user(PU/SU) activity and mobility, which result in non-determinacy. This paper studies the spectrum allocation for CRNs with non-deterministic bandwidth of spectrum holes. We present a novel probability density function(PDF) through order statistics as well as its simplified form to describe the statistical properties of spectrum holes, with which a statistical spectrum allocation model based on stochastic multiple knapsack problem(MKP) is formulated for spectrum allocation with non-deterministic bandwidth of spectrum holes. To reduce the computational complexity, we transform this stochastic programming problem into a constant MKP through exploiting the properties of cumulative distribution function(CDF), which can be solved via MTHG algorithm by using auxiliary variables. Simulation results illustrate that the proposed statistical spectrum allocation algorithm can achieve better performance compared with the existing algorithms when the bandwidth of spectrum holes is time-varied.

Opportunistic spectrum sharing in software defined wireless network

Over the past few decades, the world has witnessed a rapid growth in mobile and wireless networks（MWNs） which significantly change human life. However, proliferating mobile demands lead to several intractable challenges that MWN has to face. Software-defined network is expected as a promising way for future network and has captured growing attention. Network virtualization is an essential feature in software-defined wireless network（SDWN）, and it brings two new entities, physical networks and virtual networks. Accordingly, efficiently assigning spectrum resource to virtual networks is one of the fundamental problems in SDWN. Directly orienting towards the spectrum resource allocation problem, firstly, the fluctuation features of virtual network requirements in SDWN are researched, and the opportunistic spectrum sharing method is introduced to SDWN. Then, the problem is proved as NP-hardness. After that, a dynamic programming and graph theory based spectrum sharing algorithm is proposed.Simulations demonstrate that the opportunistic spectrum sharing method conspicuously improves the system performance up to around 20%–30% in SDWN, and the proposed algorithm achieves more efficient performance.

Research on Comparison and Evaluation Studies of Several Smoothing Denoising Method Based on γ-ray Spectrum Detector

The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI （TI） gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothing filtering methods are proposed to solve the problem. These methods include adopting method of arithmetic moving average, center of gravity, least squares of polynomial, slide converter of discrete funcion convolution etc. The process of spectrum data is realized, and the results are assessed in H/FWHM（ Peak High/Full Width at Half Maximum） and peak area based on the Matlab programming. The results indicate that different methods smoothed spectrum have respective superiority in different ergoregion, but the Gaussian function theory in discrete function convolution slide method is used to filter the complex y-spectrum on Embedded system nlatform, and the statistical fluctuation of y-snectrum filtered wall.

Power Allocation for Sensing-Based Spectrum Sharing Cognitive Radio System with Primary Quantized Side Information

Spectrum access approach and power allocation scheme are important techniques in cognitive radio(CR) system,which not only affect communication performance of CR user(secondary user,SU) but also play decisive role for protection of primary user(PU).In this study,we propose a power allocation scheme for SU based on the status sensing of PU in a single-input single-output(SISO) CR network.Instead of the conventional binary primary transmit power strategy,namely the sensed PU has only present or absent status,we consider a more practical scenario when PU transmits with multiple levels of power and quantized side information known by SU in advance as a primary quantized codebook.The secondary power allocation scheme to maximize the average throughput under the rate loss constraint(RLC) of PU is parameterized by the sensing results for PU,the primary quantized codebook and the channel state information(CSI) of SU.Furthermore,Differential Evolution(DE) algorithm is used to solve this non-convex power allocation problem.Simulation results show the performance and effectiveness of our proposed scheme under more practical communication conditions.

基于最优控制理论的高超声速飞行器轨迹生成方法

针对新型高超声速飞行器目标的实际观测场景不足、真实飞行数据难获取等导致对反导雷达目标跟踪架构、算法难以针对性优化的问题,基于最优控制理论提出了一种高超声速飞行器全阶段轨迹生成方法.利用hp-自适应伪谱法,将轨迹生成方法对应的最优控制问题转化为非线性规划问题进行求解,并输出全阶段目标飞行运动状态数据.仿真结果表明,生成的飞行场景数据完整、仿真程度高,验证了该方法的有效性.

海岛县域有机更新中的“老城新态度”——温州市洞头区中心街策划与设计

县域城市更新是我国当前和下一阶段城镇化建设的重要方向。温州市洞头区中心街更新所面临的挑战在海岛县域老旧街区更新中具有较强的代表性。本项目从可持续发展理念出发,平衡处理街区更新所面临的旅游与民生、保护与发展和传统与现代三对主要矛盾,提出整体性、连续性、动态性和创新性四大“老城新态度”。通过完善社区功能、植入旅游业态、实施关键节点更新等策略,对中心街功能进行修补与重新激活;通过打造特色鲜明的重点建筑、增补开放空间、优化沿街立面、改善步行环境等措施,对中心街空间形态进行改造和提升,从而创造一个兼顾经济、社会、文化和生态的可持续发展社区,以期为海岛县域城市更新提供可资借鉴的经验。

考虑风机及光伏机组三状态的微电网混合储能双层容量配置模型

传统的微网在配置储能时很少考虑风机以及光伏机组的多状态运行,其配置模型不具有普适性。因此提出一种考虑风、光三状态的改进微电网混合储能容量配置双层规划模型,同时提出了引入系数和并离网系数,灵活地对不同类型的微源以及并离网进行选择和组合,使其适用性更加广泛。模型上层在容量约束内随机选取一组风、光容量初始值,建立风机以及光伏机组三状态模型;下层根据上层导入的风、光初始容量,计及可靠性计算其出力,建立微网总成本最小为目标的配置模型,利用傅里叶变换对一个周期内的缺额功率进行频谱分析,确定混合储能以及联络线出力,并将结果传到上层,利用自适应遗传算法迭代出风光容量的最优解,并求出混合储能的最优配置结果。最后采用实际微网系统进行算例分析,结果表明所建模型可同时适用微网孤岛与并网运行方式。

针对缺陷根源定位的测试用例生成技术

缺陷根源定位是软件调试的重要阶段,基于频谱的缺陷根源定位方法是软件自动化调试研究中的热点问题,但其定位效果很大程度上取决于测试用例的质量。不同类型软件的测试输入通用性差,随机生成的测试输入则存在过拟合或混杂项过多的问题,导致分析结果误差较大,致使目前该类技术的应用场景有限。针对测试用例生成问题,提出了基于崩溃路径的分阶段探索方法Dgenerate,并实现原型工具Dloc。首先利用二进制插桩手段在程序执行输入阶段于基本块中插桩路径信息,根据此信息将原始测试输入划分为普通型和引导型;然后利用动态能量调度算法探索崩溃相关路径生成高质量的测试用例;最后在原始程序中执行测试用例并追踪执行时信息,通过统计分析的方法有效地定位到程序缺陷根源的位置。文中选取了6个不同类型软件中的15个真实CVE漏洞进行实验,结果显示Dloc生成的测试用例与已有技术相比可以将定位效率平均提升75%,并且Dloc能够以87%的准确性在评分前五的位置中输出缺陷根源相关代码片段,验证了所提方法系统的可行性和实用性。

沉浸式媒介中音频可视化技术的创新性研究

计算机音频可视化技术是将音频信号转化为可视化形式的技术。通过音频可视化,可以呈现音频信号的频谱特征、时间特征和空间特征等信息。在交互展览等领域中,音频可视化技术可以增强用户体验和参与感,使得观众可以更直观地感受音频的魅力。在介绍音频可视化交互展览的应用和列举行业内实际应用的基础上,对音频信号采集及音频信号格式、频谱特征分析、音频相关采样数据映射等方面进行了分析,并着重介绍了如何利用Houdini编程实现音频可视化。

融合代码静态特征和频谱的软件缺陷定位技术

基于频谱的缺陷定位(spectrum-based fault localization,SBFL)通过分析测试用例的覆盖信息和执行结果信息进行快速定位,是目前最常用的缺陷定位技术。然而,该方法未能充分利用代码中隐含的语义和结构信息。若能将缺陷预测中使用到的代码结构信息和频谱信息融合使用,将有助于进一步提升缺陷定位的效果。为此,提出了一种融合代码静态特征和频谱的软件缺陷定位(fault localization combing static features and spectrums,FLFS)技术。首先,从Halstead等度量元集合中选取度量元指标并进行修改,以适用于度量代码的方法级特征;然后,根据选取的度量元指标提取程序中各个方法的静态特征并用于训练缺陷预测模型;最后,使用缺陷预测模型预测程序中各方法存在缺陷的预测可疑度,并与SBFL技术计算的频谱可疑度进行融合,以定位缺陷所在方法。为验证FLFS的有效性,将其与两种定位效果最好的SBFL技术DStar和Ochiai在Defects4J数据集上进行了对比实验。结果表明,FLFS具有更好的缺陷定位性能,对于E inspect@n指标,当n=1时,FLFS相比DStar和Ochiai分别多定位到16和10个缺陷;对于MRR指标,FLFS相比DStar和Ochiai分别提升了4.13%和1.08%。

低阶煤在无氧和有氧升温中产生CO规律研究

利用程序升温氧化和时间分辨红外光谱仪实验装置,开展了大南湖一矿3#煤层无氧和有氧升温氧化实验,分析了在升温氧化过程中CO体积分数变化规律及CO吸收峰在时间分辨红外光谱仪的光谱图,阐明了煤在无氧和有氧升温过程中CO产生规律。结果表明:室温至200℃,此阶段不产生CO或产生极少量的CO;400~700℃,煤样失重显著增加,热重曲线快速下降,煤分子中的某些共价键发生断裂,产生了一定量的CO,其峰值约为2.3×10^(-5)。煤在有氧条件下产生CO的初现温度为36℃,煤温低于189℃时,CO体积分数与煤温之间符合幂指数变化关系,111℃是煤进入加速氧化阶段的临界温度。

基于条件执行切片谱的多错误定位

基于程序谱的错误定位技术由于其较高的定位效率已成为当前软件调试领域研究热点之一.这种技术通常根据测试覆盖信息计算程序语句发生错误的可疑度来进行错误定位.然而,这种技术会随着程序中错误数目的增多效率不断下降.鉴于此,提出了一种基于条件执行切片谱的多错误定位技术(conditioned execution slicing spectrum-based multiple fault localization,CESS-MFL),以提高多错误定位的效率.CESS-MFL技术首先根据输入变量的谓词条件构建错误相关条件执行切片的谱矩阵,然后依次计算错误相关条件执行切片中的元素(语句或语句块)的可疑度,并生成可疑度报告.实验验证了CESS-MFL技术比当前流行的基于程序谱的Tarantula技术、基于程序切片的Intersection技术、Union技术有更高的多错误定位效率,并且可在有效的时间和空间复杂度内完成.

一种基于层次切片谱的软件错误定位技术

传统的软件错误定位技术通常利用测试覆盖信息计算程序语句发生错误的可疑度进行软件错误定位,但是这种定位技术没有充分考虑程序本身固有的依赖信息,缺乏语句筛选,从而使错误定位的精度受限.提出了一种基于层次切片谱的错误定位技术,以提高面向对象程序中的错误定位效率.这种技术首先分析程序不同粒度层次元素(包、类、方法以及语句)之间的依赖信息,对可能发生错误的元素进行筛选,缩小错误查找范围;在此基础上,建立了层次切片谱模型,并定义了一种可疑度度量方法;最后根据该可疑度结果从大到小的顺序进行错误定位.通过实验验证了基于层次切片谱的错误定位技术的有效性,且比基于程序谱的Tarantula技术、Union技术、Intersection技术效率更高.