Refinement of the Proposed Gamma-Ray Burst Time Delay Model

This paper is the second instalment in our study of the observed time delay in the arrival times of radio photons emanating from Gamma Ray Bursts (GRBs). The mundane assumption in contemporary physics as to the cause of these pondersome time delays is that they are a result of the photon being endowed with a non-zero mass. While we do not rule out the possibility of a non-zero mass for the photon, our working assumption is that the major cause of these time delays may very well be that these photons are travelling in a rarefied cosmic plasma in which the medium’s electrons interact with the electric component of the Photon, thus generating tiny currents that lead to dispersion, hence, a frequency-dependent speed of Light (FDSL). In the present instalment, we “improve” on the model presented in the first instalment by dropping the assumption that the resultant pairs of these radio photons leave the shock front simultaneously. The new assumption of a non-simultaneous— albeit systematic—emission of these photon pairs allows us to obtain a much more convincing and stronger correlation in the time delay. This new correlation allows us to build a unified model for the four GRBs in our sample using a relative distance correction mechanism. The new unified model allows us to obtain as our most significant result a value for the frequency equivalence of the interstellar medium (ISM)’s conductance ν* ~ 1.500 ± 0.009 Hzand also an independent distance measure to the GRBs where we obtain for our four GRB samples an average distance of: ~69.40 ± 0.10, 40.00 ± 0.00, 58.40 ± 0.40, and 86.00 ± 1.00 Mpc, for GRB 030329, 980425, 000418 and 021004 respectively.

PERFORMANCE ANALYSIS AND SIMULATION OF VARIOUS BURST TIME PLAN GENERATION METHODS IN BROADBAND SATELLITE MULTIMEDIA SYSTEM

The Burst Time Plan(BTP) generation is the key for resource allocation in Broadband Satellite Multimedia(BSM) system.The main purpose of this paper is to minimize the system response time to users' request caused by BTP generation as well as maintain the Quality of Service(QoS) and improve the channel utilization efficiency.Traditionally the BTP is generated periodically in order to simplify the implementation of the resource allocation algorithm.Based on the analysis we find that Periodical BTP Generation(P-BTPG) method cannot guarantee the delay performance,channel utilization efficiency and QoS simultaneously,especially when the capacity requests arrived randomly.The Optimized BTP Generation(O-BTPG) method is given based on the optimal scheduling period and scheduling latency without considering the signaling overhead.Finally,a novel Asynchronous BTP Generation(A-BTPG) method is proposed which is invoked according to users' requests.A BSM system application scenario is simulated.Simulation results show that A-BTPG is a trade-off between the performance and signaling overhead which can improve the system performance insensitive to the traffic pattern.This method can be used in the ATM onboard switching satellite system and further more can be expended to Digital Video Broadcasting-Return Channel Satellite(DVB-RCS) system or IP onboard routing BSM system in the future.

Bursting-like motion induced by time-varying delay in an internet congestion control model

Time delay is an problem of intemet congestion important parameter in the control. According to some researches, time delay is not always constant and can be viewed as a periodic function of time for some cases. In this work, an internet congestion control model is consid- ered to study the time-varying delay induced bursting-like motion, which consists of a rapid oscillation burst and quies- cent steady state. Then, for the system with periodic delay of small amplitude and low frequency, the method of multiple scales is employed to obtain the amplitude of the oscillation. Based on the expression of the asymptotic solution, it can be found that the relative length of the steady state increases with amplitude of the variation of time delay and decreases with frequency of the variation of time delay. Finally, an effective method to control the bursting-like motion is pro- posed by introducing a periodic gain parameter with appropriate amplitude. Theoretical results are in agreement with that from numerical method.

Bursting oscillations in a hydro-turbine governing system with two time scales

A fast-slow coupled model of the hydro-turbine governing system （HTGS） is established by introducing frequency disturbance in this paper. Based on the proposed model, the performances of two time scales for bursting oscillations in the HTGS are investigated and the effect of periodic excitation of frequency disturbance is analyzed by using the bifurcation diagrams, time waveforms and phase portraits. We find that stability and operational characteristics of the HTGS change with the value of system parameter kd. Furthermore, the comparative analyses for the effect of the bursting oscillations on the system with different amplitudes of the periodic excitation a are carried out. Meanwhile, we obtain that the relative deviation of the mechanical torque mt rises with the increase of a. These methods and results of the study, combined with the performance of two time scales and the fast-slow coupled engineering model, provide some theoretical bases for investigating interesting physical phenomena of the engineering system.

Burst Astrophysics

This article proposes an explanation for Fast Radio Bursts (FRBs) and Gamma Ray Bursts (GRBs) through the frames of Hypersphere World-Universe Model (WUM). WUM predicts that the concentration of protons and electrons in Intergalactic Plasma decreases inversely proportional to time and in present epoch equals to . The energy density of Intergalactic Plasma relative to the critical energy density equals to . Time delay of FRBs is calculated through these characteristics. A number of experimental results, including the redshift for FRB 150418, remarkable brightness for FRB 150807, and transient gamma-ray counterpart for FRB 131104 are explained. The distance to FRB 150807 object is predicted to be ~800 Mpc. WUM holds that all macroobjects (galaxies, stars, and planets) contain a core composed of Dark Matter Particles. GRBs are explained as a sum of contributions of multicomponent dark matter annihilation. The spectra of such bursts depend on the composition of the Cores.

鲜水河构造带隧道高地应力区岩爆特性分析

研究目的:青藏高原持续隆升,导致鲜水河构造带及邻区高地应力特征突出,地应力场极其复杂,研究高地应力的孕灾特征有助于隧道岩爆的风险防控,特别是时滞型岩爆的孕灾和致灾机理的研究。本文阐述鲜水河构造带地貌、地层岩性、构造及地应力场特征的孕灾总体认识,通过对该区域隧道近10 km约1300次岩爆统计,从发生概率、等级、埋深、位置、时间、距离等多角度研究岩爆特征,对发生的5次时滞型岩爆和隧道时效性变化特征进行分析,展望后续岩爆研究的重点。研究结论:(1)鲜水河构造带及邻区受高地应力影响,隐伏小微构造发育且无规律,为岩爆创造了特殊的孕灾环境,岩爆发生的随机性大;(2)该区域隧洞岩爆等级以轻微岩爆为主,具有“分区破裂”和脆性变形特征,时滞型岩爆一定程度上具有“继承性”;(3)建议加强沟谷应力场低埋型岩爆和滞后型岩爆或硬岩潜在时效破坏的监测研究;(4)本文研究成果可为类似高地应力环境下岩爆预测和防控提供借鉴。

Influences of Network Delay on Quality of Experience for Soft Objects in Networked Real-Time Game with Haptic Sense

In this paper, we investigate the influences of network delay on QoE (Quality of Experience) such as the operability of haptic interface device and the fairness between players for soft objects in a networked real-time game subjectively and objectively. We handle a networked balloon bursting game in which two players burst balloons (i.e., soft objects) in a 3D virtual space by using haptic interface devices, and the players compete for the number of burst balloons. As a result, we find that the operability depends on the network delay from the local terminal to the other terminal, and the fairness is mainly dependent on the difference in network delay between the players’ terminals. We confirm that there exists a trade-off relationship between the operability and the fairness. We also see that the contribution of the fairness is larger than that of the operability to the comprehensive quality (i.e., the weighted sum of the operability and fairness). Assessment results further show that the output timing of terminals should be adjusted to the terminal which has the latest output timing to maintain the fairness when the difference in network delay between the terminals is large. In this way, the comprehensive quality at each terminal can be maintained as high as possible.

低轨卫星短突发通信时频同步算法

低轨卫星短突发通信具有多普勒频偏和多普勒变化率较大、突发符号较短和突发信号导频长度受限等特点,采用传统的时频同步算法在低信噪比条件下性能较差。为了提高时间同步和频偏估计性能,准确完成同步过程,基于时分多址(Time Division Multiple Access,TDMA)接入帧结构提出一种新的时频同步算法。该算法采用二维搜索算法进行整数倍的时延估计和粗频偏估计;在补偿大频偏和整数倍时延后,估计小数倍时延;采用结合低通滤波的快速傅里叶变换(Fast Fourier Transform,FFT)算法进行精频偏估计。仿真结果表明,每符号能量与噪声功率谱密度比值(Ratio of Symbol Energy to Noise Power Spectral Density,E_(s)/N_(0))为4.5 dB时,时延检测概率准确率达到99.99%,整体解调性能相较于M&M等算法有2 dB以上的性能提升。

基于抛物线内插的位定时算法研究

位定时同步是数字通信接收机的重要组成部分,定时同步的准确性直接影响整个系统的性能。突发通信一般采用数据辅助的前馈式位定时同步结构。针对突发通信短时的特点,搭建了一种基于抛物线内插的位定时同步估计的低复杂度算法。该算法仅需利用信息帧头捕获到相关锋;然后,根据抛物线误差估计算法对当前采样信号进行误差估计,再选取合适的插值滤波器进行插值计算,获得最佳采样点,从而实现突发信号的定时同步过程。结果表明,该算法实现简单,在低信噪比的情况下,能够满足突发信号快速实现定时同步的需求,且其性能仍接近克拉美罗界。

小口径定距空爆弹末端防空拦截实时模拟及开舱距离研究

针对现有小口径定距空爆弹末端防空拦截及开舱距离模拟中,无法体现开舱后子弹云团与目标的动态交会过程,并忽略了定距空爆引信实际启动规律,导致毁伤效能评估不准确的问题,开展小口径定距空爆弹末端防空拦截实时模拟及开舱距离进行研究。通过建立多束定向预制破片战斗部、弹目交会及以巡航导弹为拦截目标的等效目标数值模型,搭建小口径定距空爆弹末端防空拦截实时模拟平台。基于实时模拟平台,引入武器系统误差与定距空爆引信实测启动规律,分析炮弹在不同射击距离下开舱距离与毁伤效能的关系,并对小口径定距空爆弹引信技术发展方向进行展望。研究结果表明,引信实际启动规律使得最优毁伤效能随射击距离的增加而减少的幅度增大,在射击远距离目标时,0~20 m的开舱距离内都存在着较高的完全脱靶率。

基于转底炉工艺的造球参数优化研究

转底炉直接还原工艺是目前处理冶金粉尘的典型工艺,能充分回收利用粉尘中的铁、碳和锌等有用组分。本研究首先对粉尘的化学成分和粒径进行了分析与检测,再基于圆盘造球的方法,研究了水分对生球爆裂温度的影响,优化了转底炉的造球参数。结果表明,生球干燥后的水分应控制在4.0%以下,造球时间、黏结剂含量和碳氧质量比对成球率和球团的性能影响显著,当造球时间为12 min、膨润土含量为3.0%、碳氧质量比为0.7时,球团的性能最好,球团合格率为60.32%。

基于唯象学模型的洛伦兹破缺限制研究

洛伦兹不变性是物理学中的基本对称性原理之一,但一些量子引力理论指出洛伦兹对称性可能会在高能阶段被打破从而产生洛伦兹破缺现象,使光子的传播速度与其自身能量相关而非恒定光速。目前在唯象学模型下可以利用高能探测器对γ射线中光子的时间延迟和谱延迟进行洛伦兹破缺能标限制。基于唯象学模型,通过比对伽马暴中两种延迟的限制结果,发现谱延迟限制普遍小于时间延迟限制3~4个量级。为了使结果更具置信度,计算了GRB 190114C在1~14s时间段的时间延迟限制和同时间段的谱延迟限制,比对结果仍是谱延迟限制小3个量级,这主要是谱延迟的特性所致。

冲击性煤体应力结构时间效应试验研究

煤矿工程中蕴含复杂的应力结构时间效应问题,与冲击地压灾害的发生与防治密切相关。针对冲击性煤体的应力结构时间效应开展试验研究,在陕西、甘肃以及内蒙古3个冲击地压矿井取得煤岩块体加工试件,通过煤单轴压缩动静载及蠕变试验研究加载速率的应力时间效应,采取长时分段试验方法研究煤原位解除条件下的应力时间效应,开展煤浸水以及煤岩组合试验研究结构时间效应。结果表明:煤体单轴抗压强度与加载速率具有正相关性,与原位解除时长和浸水时间具有负相关性,煤岩结构时间效应下的组合模式对其能量及强度属性有显著影响,冲击性煤体表现出应力与结构2个方面的时间效应。依据试验结果,提出塑限结构来解释应力作用下煤岩体的不可逆变形,再通过构建塑限结构时间效应模型,对比非弹性应变与不可逆应变的数值近似性,对冲击性煤体塑限应变特性进行了验证。

突发式无线通信的快速AGC控制方法研究

针对突发式无线通信自动增益控制(automatic gain control,AGC)存在的器件非线性、响应时延及调制峰均比问题,提出一种基于模糊控制和比例微分控制的快速AGC控制方法。设计系统结构,分析AGC控制的影响因素,进行模糊控制粗调和PD控制精调,给出软件流程,并在常温环境下进行系统实验。实验结果表明:相比传统AGC方案,该方案可在大动态范围实现快速收敛。

断层破碎带突水的时效特性研究

突水属重大地质灾害 ,一直引起人们的关注。本文认为突水瞬间表现一个综合效应下的瞬时地质事件。突水前表现一个与时间有关的地质作用过程。事件与过程都受多因素的影响 ,而且工程地质作用过程和突水瞬间与岩体由弹性变形 -阻尼变形 -常速流动变形 -加速流动变形相对应。突水具有时效特征。

煤层底板断裂突水时间弱化效应机理的仿真模拟研究——以开滦赵各庄煤矿为例

采用现场地应力实测、室内不同含水量情况下的断裂带物质的单轴、三轴常规和流变力学试验以及弹塑性三维可视化数值仿真模拟(FLAC^(3D))等研究,获得了断裂带物质弱化效应力学参数,阐述了其弱化机理和主要控制因素,提出了煤层底板断裂构造实水时间弱化效应的新概念。对赵各庄矿13水平(—1100m)F_8断层破碎带穿越的首采区安全回采方案做出了预测和评价。

开滦赵各庄矿断裂滞后突水数值仿真模拟

针对开滦赵各庄矿 13水平 (- 110 0m)F8断层破碎带穿越的首采区的安全回采评价问题 ,通过现场地应力实测、室内不同含水量情况下的断裂带物质的单轴、三轴常规和流变力学试验以及反演所确定的力学参数 ,对其进行弹塑性三维可视化数值仿真模拟 ,深刻地阐述了其弱化机理和主要控制因素 ,提出了煤层底板断裂构造突水时间弱化效应的新概念 ,并对不同水压、不同时效阶段条件下赵各庄矿 13水平首采区的安全回采方案作出了预测评价 .

高应力硬岩地区岩体结构对地下洞室围岩稳定的控制效应研究

官地水电站地下厂房属典型的硬岩地区深埋大型地下洞室群,其重要特点是同时面临高地应力和结构面发育这2个不利条件,实测最大主应力为25～35 MPa,厂区无大的断层和软弱结构面,但错动带和裂隙十分发育。通过对地下洞室群施工过程中出现的围岩局部失稳破坏现象进行全面的分析整理,对三大洞室的岩体结构特征和围岩变形破坏模式进行系统的分析、比较和总结,从而对影响围岩稳定的两大控制因素——地应力和岩体结构对官地地下厂房洞室群围岩稳定的影响程度和方式进行分析和对比。研究表明,由于三大洞室围岩类别以II类为主,岩体结构以块状～次块状结构为主,围岩具有较高的力学强度和强度应力比,从而具有较强的抵抗应力破坏的能力;岩体结构对地下厂房围岩变形与稳定的控制作用较地应力则更为明显,地下洞室群开挖过程中出现的局部失稳或较大变形多与不利方位的结构面直接相关。三大洞室围岩岩体结构特征总体上的相似性非常明确,反映在三大洞室围岩的变形特征和破坏模式上具有很好的统一性。然而,三大洞室的岩体结构特征也存在一定的差异,导致岩体结构影响围岩稳定的方式和程度有所不同。结构面发育造成的另一个不利影响是为坚硬岩体在高地应力条件下产生卸荷时效变形提供了内部条件。因此,在强度应力比较高的硬岩地区,应充分重视岩体结构及其演化对围岩变形和稳定的控制效应。

纺织品胀破性能试验条件

在对胀破强度测试标准GB/T 7742.1—2005《纺织品织物胀破性能第1部分胀破强力和胀破扩张度的测定液压法》的试验条件进行研究时发现:试验面积与胀破强度有一定的反比例关系,对于同一试样,旧标准推荐试验面积7.3 cm2下的胀破强度约为现行标准推荐试验面积50 cm2下胀破强度的3倍;胀破速度对胀破强度影响较小,胀破速度提高时胀破强度会略微增加;胀破速度和胀破时间在小范围内调整时具有一定的线性关系,按比例调整胀破速度可以快速获得标准规定的胀破时间;该测试方法具有较好的精密度,均匀试样测试结果的变异系数CV值小于1%。

滑坡灾害短期临滑预报监测新途径研究

由于滑坡灾害的复杂性,迄今为止,尚未形成经得起大量实践验证的预报理论与方法,现仍然是地质灾害学中正在探索研究而未完全解决的难题.通过对滑坡灾害研究史、预测预报、监测技术的分析,认为在滑坡进入加速变形至剧变形破坏阶段,地表及深部监测网点及其设施遭受破坏,无法继续利用“点”式测量方法采集监测数据的情况下,地面三维激光扫描仪可不受干扰独立进行滑坡的“面”式测量,为预测预报滑坡的发生时间提供第一手连续可靠的数据资料,可进一步提高滑坡灾害预测预报的精度.