基于商品市场能数的商品竞争力提升路径探讨

"顾客让渡价值"概念反映了顾客价值和顾客成本两个方面,可以对商品的市场竞争力进行一定程度的描述,但因其是绝对数而非相对数,所以很难对不同类型尤其是价值差异较大的商品的竞争能力进行比较。本文以商品市场能数为分析工具,提出企业提升顾客让渡价值进而提升商品竞争力的路径。

塞式喷管多参数性能优化计算

从影响塞式喷管推力性能的因素中总结出内喷管倾角、内膨胀比、总膨胀比、燃气总压和飞行高度这五个主要因素 ,并以推力最大为目标函数运用枚举和逐层优化的方法对上述五个参数的取值进行优化计算 ,提出了对这五个参数进行优化取值的方法并得到了相关结论。其结论可为实际的塞式喷管发动机设计研制提供部分的理论依据 。

用时序参数诊断频域变化

频域分析是各种动态信号处理的重要内容。本文基于Fourier分析和时序分析的极大熵谱估计理论,提出一种可用于诊断频域特征变化的时域特征参数。该特征参数的主要特点是可利用时域信息来快速反映频域特征的变化,且计算简单,运算速度快,适于在线诊断频域特征变化的均合。理论和实验证明该特征参数的理论和方法是合理的。

Enabling Technologies for Autonomous Robotic Systems in Manufacturing

Research of autonomous manufacturing systems is motivated both by the new technical possibilities of cyber-physical systems and by the practical needs of the industry.Autonomous operation in semi-structured industrial environments can now be supported by advanced sensor technologies,digital twins,artificial intelligence and novel communication techniques.These enable real-time monitoring of production processes,situation recognition and prediction,automated and adaptive(re)planning,teamwork and performance improvement by learning.This paper summarizes the main requirements towards autonomous industrial robotics and suggests a generic workflow for realizing such systems.Application case studies will be presented from recent practice at HUN-REN SZTAKI in a broad range of domains such as assembly,welding,grinding,picking and placing,and machining.The various solutions have in common that they use a generic digital twin concept as their core.After making general recommendations for realizing autonomous robotic solutions in the industry,open issues for future research will be discussed.

Mechanical response and dilatancy characteristics of deep marble under different stress paths:A sight from energy dissipation

Dilatancy is a fundamental volumetric growth behavior observed during loading and serves as a key index to comprehending the intricate nonlinear behavior and constitutive equation structure of rock.This study focuses on Jinping marble obtained from the Jinping Underground Laboratory in China at a depth of 2400 m.Various uniaxial and triaxial tests at different strain rates,along with constant confining pressure tests and reduced confining pressure tests under different confining pressures were conducted to analyze the mechanical response and dilatancy characteristics of the marble under four stress paths.Subsequently,a new empirical dilatancy coefficient is proposed based on the energy dissipation method.The results show that brittle failure characteristics of marble under uniaxial compression are more obvious with the strain rate increasing,and plastic failure characteristics of marble under triaxial compression are gradually strengthened.Furthermore,compared to the constant confining pressure,the volume expansion is relatively lower under unloading condition.The energy dissipation is closely linked to the process of dilatancy,with a rapid increase of dissipated energy coinciding with the beginning of dilatancy.A new empirical dilatancy coefficient is defined according to the change trend of energy dissipation rate curve,of which change trend is consistent with the actual dilatancy response in marble under different stress paths.The existing empirical and theoretical dilatancy models are analyzed,which shows that the empirical dilatancy coefficient based on the energy background is more universal.

Effect of benzoxazine resin on mechanical properties of nitrile rubber composites: Experiment and molecular simulation

Benzoxazine resin,being a new type of phenolic resin deve-loped to overcome the shortcomings of traditional phenolic resins,has been synthesized from phenol,formaldehyde and amine,and does not require solvent elimination or monomer purification to obtain a relatively clean precursor.It has potential application in the field of aerospace due to its low expansion coefficient,high weather resistance,high carbon yield,good mechanical strength,and excellent ablation resistance[1].It can be mixed with various other resins or polymers to produce new resins with a broad range of applications[2-3].

5052铝合金热压缩变形流变应力

在Gleeble-1500热模拟机上，采用高温等温压缩，在应变速率为0．001—10s^-1和变形温度为300℃-500℃条件下对5052铝合金的流变应力行为进行了研究。结果表明：在应变速率为0．1s^-1（变形温度为420℃-500℃）以及应变速率为0．01和0．001（变形温度为300℃-500℃）时，5052铝合金热压缩变形出现了明显的峰值应力，表现为连续动态再结晶特征；在其他变形条件下存在较为明显的稳态流变特征。可采用Zener—Hollomon参数的双曲正弦函数来描述5052铝合金高温变形时的流变应力行为；在获得的流变应力盯解析表达式中A、α和n值分别为12．68×10^11s^-1，0．023MPa^-1和5．21；其热变形激活能Q为182．25kJ／mol。

离心转子式选粉机的分级性能

通过模型实验，系统地研究了转子转速、处理风量、加料速度等主要操作参数对离心转子式选粉机分级性能的影响规律。结果表明，离心转子式选粉机具有良好的分级性能，为选粉机在实际生产中确定适宜的操作参数提供了理论依据。

几种增塑剂与PVC树脂混容性研究

本文用测清晰点的方法,测定了DBP、DOP、DOTP以及DBP+DOTP等增塑剂与不同型号PVC树脂之间相互作用参数κ值。并以此讨论了增塑剂与PVC树脂的混容性能。

恒定组成封闭体系的热力学关系式

用数学分析方法研究总结了恒定组成封闭体系的热力学函数之间的关系式,为较好地研究体系热力学参数之间的关系奠定基础,也为物理化学教学提供一定的思考问题的方法和理论。

Determination of local constitutive behavior and simulation on tensile test of 2219-T87 aluminum alloy GTAW joints

The local and global mechanical responses of gas tungsten arc welds（GTAW） of a 2219-T87 aluminum alloy were investigated with experiment and numerical simulation.Digital image correlation（DIC） was used to access the local strain fields in transversely loaded welds and to determine the local stress-strain curves of various regions in the joint.The results show that the DIC method is efficient to acquire the local stress-strain curves but the curves of harder regions are incomplete because the stress and strain ranges are limited by the weakest region.With appropriate extrapolation,the complete local stress-strain curves were acquired and proved to be effective to predict the tensile behavior of the welded joint.During the tensile process,the fracture initiates from the weld toes owing to their plastic strain concentrations and then propagates along the fusion line,finally propagates into the partially melted zone（PMZ）.

Comparative Analysis on Growth and Morphology in Yangtze River ♀,Zhujiang River ♂ and Their F_1 Hybrids of Juvenile Grass Carp

[ Objective] The aim of this study was to investigate the growth and morphological characteristics of juvenile hybrids of grass carp. [Method] Three inbred generations of YR （Yangtze River stock ♀×Yangtze River stock ♂ ）, ZR （Zhujiang River stock ♀ ×Zhujiang River stock♂ ） and hybrids F1 （ Yangtze River stock ♀ × Zhujiang River stock ♂ ） were established, and their growth or morphological data were also measured. [ Result] The orders of body weight, standard length and absolute growth rate were F1 〉 ZR 〉 YR. No significant difference was found in body weight or standard length of 50 day-old generations （ P〉0. 05）, while there was an extremely significantly difference in those of 170 day-old generations （ P 〈0.01 ）. However, the absolute growth rate of F1 was 20.00% and 50.00% higher than that of ZR and YR respectively, and no significant difference was found between F1 and ZR （ P 〉 0.05）, but significant difference between F1 and YR （ P 〈 0.05）. F1 showed a significant hybrid vigor with rate of 20.09%. There was no significant difference among three inbred generations in standard length/total length （ P 〉 0.05）, while significant difference in head length/total length, body height/standard length and body width/standard length （ P 〈 0.05）, which indicated that F1 had the characteristics of shorter head, higher and wider body. [ Conclusion]F1 has advantages in growth performance and morphological characteristics.

NEW ALGORITHM FOR RECEIVER AUTONOMOUS INTEGRITY MONITORING

A new integrity metric for navigation systems is proposed based on the measurement domain. Proba-hilistic optimization design offers tools for fault detection by considering the required navigation performance （RNP） parameter and the uncertainty noise. The choice of the proper performance parameter provided the single-valued mapping with the missed detection probability estimates the probability of failure. The desirable characteristics of the residual sensitivity matrix are exploited to increase the efficiency for identifying erroneous observations. The algorithm can be used to support the performance specification and the efficient calculation of the integrity monitoring process. The simulation for non-precision approach （NPA） validates both the viability and the effectiveness of the proposed algorithm.

Data synchronization in IMU/GPS integrated measurement system of vehicle motion parameters

To realize the data synchronization between the inertial measurement unit （IMU） and the global positioning system （GPS）, the synchronization technology in the IMU/GPS integrated measurement system of vehicle motion parameters is studied. According to the characteristics of the output signals of the IMU and the GPS, without the IMU synchronization signal, the synchronization circuit based on CPLD is designed and developed, which need not alter the configurations of the IMU and GPS. Experiments of measuring vehicle motion parameters, which rely on the synchronization circuit to realize IMU/GPS data synchronization, are made. The driving routes in experiments comprise a curve and a straight line. Experimental results show that the designed circuit can accurately measure the synchronization time difference and the IMU period, and can effectively solve the data synchronization in IMU/GPS integration. Furthermore, the IMU/GPS integrated measurement system based on the synchronization circuit can measure and calculate many vehicle motion parameters in high frequency mode.

Feature Extraction of Acoustic/Seismic Signal of Target

A microphone and a seismic sensor always become a basic unit of UGS(unattended ground sensors) system. The mechanism of acoustic and seismic property of target and its propagation are described. The acoustic and seismic signals of targets are analyzed with time frequency distribution according to its non stationary property. Narrow band energy function (NEF) and local power spectral density (LPSD) are proposed to extract features for target identification. Experiment results show that local power spectral density indicates corresponding target clearly.

Influence of filling parameters on fatigue properties of A357 alloy produced by counter pressure plaster mold casting

The influence of filling parameters including pouring temperature, filling speed, boost pressure and synchronous pressure on the fatigue of A357 alloy produced by counter pressure plaster casting was studied. The Taguchi method was used to investigate the relationship between the fatigue performance and filling parameters. The results show that filling speed is the most significant factor among the four parameters. Synchronous pressures is less influential on the fatigue life when the value of synchronous pressure is from 400 kPa to 600 kPa.

Shear resistance performance of steel-concrete-steel composite shear wall

For a deeper understanding of the shear resistance performance of the steel-concrete-steel composite shear wall, the main influence factors such as the thicknesses of the steel plates and the concrete, the strength grades of the concrete and the span-depth ratios of the composite wall, which have impacts on the shear resistance performance of the composite shear wail, are analyzed by the numerical simulation method. Meanwhile, the simplified calculation formulae of the initial elastic lateral-resisting stiffness and the shear bearing capacity of the composite shear wall are also proposed. The research shows that with the increase in the thicknesses of the steel plates and the concrete and the increase in the strength grades of the concrete, the shear performance of the shear wall improves obviously; the span-depth ratios of the composite wall have a significant effect on the initial elastic lateral- resisting stiffness, but a small effect on the shear bearing capacity. Comparing the results of the simplified calculation formulae with those of the nonlinear finite element method, it is obvious that the presented formulae are reasonable and meet the real force state of the structure. These conclusions can serve as a preliminary design reference for the steel-concrete- steel composite shear wall.

Mechanical model for failure modes of rock and soil under compression

The failure modes of rock and soil under compression are complex phenomena that have not been explained in a mechanical perspective. However, large amounts of studies indicate that the failure modes of rock and soil samples can be categorized into eight types. In this work, the inner tensile stress and the dissipation and conversion of energy of rock and soil under compression are analyzed, then the effective conversion coefficient of energy is deduced, thus the tensile failure criterion of rock and soil under compression is established. Combined with the shear strength criterion of Mohr–Coulomb, a tensile joint shear strength criterion for rock and soil under compression is built. Therefore, a mechanical criterion model concerning the failure modes of rock and soil under compression is established and verified by tests. This model easily explains the test results in the existing literature and many natural phenomena, such as collapse.