Galileo接收机多径抑制方法的改进

旁瓣是影响跟踪稳定性的重要误差来源。为解决这一问题,提出 了 一种改进旁瓣消除技术,与传统的旁瓣消除技术相比其在稳定性上具有一定的优势,有效改 善了跟踪的稳定性 。针对多径对GNSS系统影响这一问题,将改进的旁瓣消除技术与窄相关技术（NC）、高分辨 率相关技术（HRC）和早迟坡度技术（ELS） 3种多径抑制技术相结合,仿真结果证明改进后 的多径抑制技术能有效提高跟踪的精度和稳定性。     

利用DME问答时序的飞机无源定位

针对多基测角交会、时差相差、时差频差定位系统复杂度高、同步要求高的问题，利用测距机（DME）系统测距模式中飞机与台站的通联关系，提出了一种对飞机无源定位的方法。已知地面DME台站位置和本机侦测点位置，通过对飞机地空测距询问信号、台站距离应答信号的到达时间、方位进行测量并进行解码分选，对解码分选结果进行关联聚类，再利用DME测距工作模式的随机询问特性进行询问-应答信号的时序匹配，最后根据配对信号的到达时间差、DME台站位置以及飞机方位对飞机进行计算定位。通过仿真分析证明了该方法的可行性，在固定DME台站位置已知的条件下该方法具有工程实践意义。     

QAM-OFDM雷达通信共享信号长时间相参积累算法

QAM-OFDM(Quadrature Amplitude Modulation-Orthogonal Frequency Division Multiplexing)雷达通信共享信号因携带随机通信信息，其脉压旁瓣的随机性较大，类似噪声的影响。针对该问题，采用基于Keystone变换的长时间相参积累算法抑制其旁瓣。在共享信号模型的基础上，分析了其脉压旁瓣受随机通信信息的影响以及采用长时间相参积累抑制其旁瓣的可行性，然后采用Keystone变换校正其长时间相参积累产生的距离单元走动，并进行多普勒模糊补偿处理。理论分析和仿真结果表明，该方法使得回波能量积累集中，能有效实现共享信号脉压旁瓣的抑制。     

小孔径超视距目标探测中的OFD-NLFM发射波形设计

针对小孔径超视距目标探测时阵列孔径减小空域滤波性能下降的问题,提出了一种正交频分非线性调频（OFD-NLFM）的发射波形设计方法。首先以正切调频函数为频率函数对发射信号进行建模,详细说明了影响脉压性能的正切函数时间副瓣电平控制因子的选择方法,重点提出一种基于凸优化的脉压信号峰值旁瓣抑制算法,建立了脉压输出噪声功率最小的优化模型并进行求解。仿真表明,提出的正交频分非线性调频信号具有较好的正交性,采用凸优化加权算法后脉压主瓣宽度比传统线性调频信号降低约1/3,峰值旁瓣为-31.22 dB,旁瓣电平平均值小于-100 dB,具备更低的抗噪声和干扰性能,从波形设计和脉压处理角度改善了空域滤波性能的不足。     

认知OFDM系统旁瓣抑制新方法

针对认知正交频分复用（OFDM）系统带外辐射（OBR）严重问题，在研究基于功率谱密度的主动干扰消除算法（PSD-AIC）模型的基础上，提出了动态PSD-AIC的方法，通过对每一子载波位置OBR的计算，比较选择出OBR取值最小处，作为对消子载波的最优位置，显著改善了系统对OBR的抑制性能（增大约10dB）。对比分析了算法的计算开销，研究了设计参数对OBR的影响，提出了实际应用时的参数选择基准。仿真结果和理论分析表明，动态PSD-AIC方法可以显著减小带外干扰。与PSD-AIC方法相比，旁瓣抑制深度可增加约10dB；与传统AIC方法相比，只需相似计算量，干扰抑制性能便可明显增加。     

基于CRC纠错与迭代干扰消除的星载AIS接收机

为了提升星载船舶自动识别系统（AIS）的卫星接收性能,提出了一种采用4 b循环冗余校验（CRC）纠错与迭代干扰消除算法的星载AIS接收方案。针对星载AIS系统中多路信号碰撞明显的情况,首先,通过分析星载AIS系统中CRC错误类型,采用比特反转的方式进行纠错;其次,对纠错后的序列进行AIS数据重构,采用迭代干扰消除方法消除重构信号,并将余下信号作为输入信号再次进入系统进行解调。仿真结果表明,和传统的CRC纠错系统相比,针对典型的两路信号碰撞情况,基于4 b CRC校验与迭代干扰消除的星载AIS系统能够带来1~2 dB的误码率增益,对星载AIS系统的性能提升有重要指导意义。     

一种线性调频信号超低旁瓣脉冲压缩方法

雷达脉冲压缩希望具有超低距离旁瓣的特征,线性调频信号采用加窗方式可达到约-35 dB的距离旁瓣电平。基于超低旁瓣电平信号设计方法,在不考虑信噪比损失条件下,提出了一种新的超低旁瓣的脉冲压缩方法,基本思想是针对给定线性调频信号,频率滤波权值采用超低频旁瓣频域信号与线性调频信号频域的比值,可以将接收端旁瓣电平输出最低到-120 dB。同时,从理论上和数值结果中分析了信噪比损失、延迟敏感性等问题。     

一种改进的基于LC-GSC的主瓣干扰抑制方法

针对线性约束广义旁瓣相消器（LC-GSC）存在主瓣干扰时天线自适应方向图会出现主瓣波束畸变及副瓣电平升高的问题,给出了一种通过阻塞矩阵对数据进行预处理的主瓣干扰抑制方法,对线性约束广义旁瓣相消器进行了改进,先利用阻塞矩阵预处理实现主瓣干扰抑制,再通过线性约束广义旁瓣相消器进行波束形成,有效地解决了波束主瓣变形及旁瓣电平升高的问题。仿真分析验证了改进方法的有效性。     

一种利用询问－应答规律对应答机定位的方法

针对双站测向定位系统复杂、同步要求高的问题,根据询问应答机的工作规律,提出了一种对应答机单站定位的方法。根据已知的地面询问站和侦收站位置,通过测量敌我识别询问和应答信号到达时间差和应答信号方位,实现了对应答机的定位;同时分析了定位误差,通过计算机仿真证明了该方法的可行性。在地面询问站已知的情况下该方法对于解决实际工程问题具有借鉴意义。     

契比雪夫加权应用被动合成孔径处理算法研究

提出了将契比雪夫加权应用于被动合成孔径处理算法。被动合成孔径技术对小孔径 基阵沿直线运动接收到的信号进行合成处理，从而达到虚拟大孔径基阵方位分辨力效果。将 契比雪夫加权应用于线阵合成孔径前后波束图的指向性研究，对主瓣宽度变化予以合理解释 。理论分析结合仿真验证表明，被动合成孔径处理算法应用契比雪夫加权可以在给定的旁瓣 高 度要求下获得等旁瓣级，等旁瓣级下可提高对弱目标信号的检测分辨能力。     

美国国际贸易法院判定美国商务部对河北兴茂轮胎有限公司非公路用轮胎“双反”措施不当案评述

美国进口商和中国出口商不满美国商务部对来自中国的某些非公路用轮胎实施反倾销和反补贴税的裁定,向美国国际贸易法院提出起诉。美国国际贸易法院裁定,美国法律没有明确规定反倾销税法是否可适用于非市场经济国家;本案中美国商务部做的"双反"裁定,在方法上不合理。本文在介绍该案的基本案情、归纳法院推理和判决的基础上,对该案涉及的法律问题做了简要评论。     

How do economic,cultural, and global-connectedness distances moderate the effect of customers’ experiences on their intention to revisit non-indigenous restaurants? Evidence from Korean restaurants

In this study, we evaluate how the effect of customers' experiences on revisit intention for non-indigenous restaurants can be moderated by economic distance (ED), cultural distance (CD) and global-connectedness distance (GD) between the country of origin for a given non-indigenous restaurant and the customer’s resident country. Surveys were conducted in seven countries across three continents, and the levels of ED, CD and GD between Korea and the seven countries were used as moderators. The findings suggest that the types of food and staff are two elements that should be emphasized in countries that are relatively close to Korea. Conversely, elements like the atmosphere of the restaurant and word of mouth should be emphasized in countries that have greater distances from Korea. Of the three distances considered in the study, GD had the strongest moderating effect on the relationship between customers’ experiences and their intentions to return to the restaurant. As a whole, the results imply that ED, CD and GD are important points of reference when considering prior experience while selecting a target country based on the strength of the restaurant’s experience management.     

The political market for immigration restrictions: Model and test

This paper addresses the important question of whether public investment spending on economic infrastructure enhances economic growth in Mexico. It estimates a Cobb-Douglas production function that includes public infrastructure capital. Using cointegration analysis, the paper estimates a vector error correction model (VECM) for the 1995?–?99 period. The results suggest that there is a long-term stable relationship among the variables included in the VECM. The evidence also indicates that both public infrastructure spending and private capital formation have a positive and highly significant effect on the rate of output growth. Finally, the impulse response functions (IRF) and the variance decompositions (VDC) of the endogenous variables in the VECM suggest that the response of private capital to public infrastructure is positive while the reverse causation is not affirmed. From a policy standpoint, the findings call into question stabilization policies that disproportionately reduce public infrastructure to meet targeted reductions in the fiscal deficit (JEL, O1, O47, O54).     

PTE,innovation capital and firm value interactions in the biotech medical industry

Unlike previous studies which only focus on the main effect between IC and FV, this research includes PTE with the gap of resource-based view. IC is a key element in creating a competitive advantage, as it has a great influence on FV. A company may put relatively less into IC if it demonstrates higher efficiency. However, previous studies have neglected the fact that relative efficiency and IC affect FV and stock returns directly and indirectly. The research period was from 2006 to 2010 and the main research methods include HRA and DEA. The main research findings include the following. (1) There is a space for improvement in terms of the total technical efficiency. (2) PTE has a significant moderating effect between IC and FV. (3) IC and PTE have a significant influence on FV. (4) Apart from PTE and stock returns, IC and FV show significant differences within the sub-industry.     

基于风险调整收益方法的企业信用风险管理研究

文章根据风险调整收益（RAROC）的原理,借鉴J.P.摩根的信用计量CreditMetrics模型中信用等级转移的思想,构建了应收账款回收期内受信企业信用状况转移矩阵,并据此计算出企业信用VaR值和经济资本CaR值,进而计算RAROC比值,可为企业信用销售决策提供依据。通过将RAROC方法引入企业信用风险管理体系,可以对企业经营活动进行基于风险的绩效考核和业绩评价,以期提高企业信用风险管理水平。     

高效液相色谱-电感耦合等离子体质谱法测定粉质化妆品中的六价铬

采用高效液相色谱（HPLC）与电感耦合等离子体质谱（ICP-MS）联用技术,建立了粉质化妆品中六价铬的测定方法。样品经0.05 mol/L氢氧化纳溶液超声振荡提取;HPLC采用Hypersil GOLD C18柱分离,以5%（v/v）甲醇-2 mmol/L四丁基硫酸氢铵水溶液（pH 4.0）作为流动相;ICP-MS测定选用碰撞池技术以消除40Ar12C对52Cr的谱学干扰。方法学研究结果表明,添加水平为0.040-2.000 mg/kg时,回收率为77.5%-107.5%,相对标准偏差（RSD）小于10%。     

Why Consumers in Developing Countries Prefer Foreign Brands: A Study of Japanese Brands in Vietnam

ABSTRACT

Building on social-identity theory, the research develops a model for understanding of the impact of consumer identification with a nation on consumers' brand evaluations. It posits that developing-country consumers' identification with a foreign (developed) nation influences three factors—consumer-based brand equity, consumer-based country image, and consumer-based brand credibility. The research was informed by data from 400 Vietnamese consumers in relation to two Japanese brands Sony and Honda and analyzed using structural equation modeling (SEM). The findings show that Vietnamese (developing-country) consumers prefer Japanese (developed-country) brands over domestic brands, when these consumers identify with the developed nation.     

Is the cure worse than the disease? The effect of emerging market MNEs on host country corruption

In recent years, there has been an exponential increase in the amount of foreign investment by emerging market multinational enterprises (EMNEs). While it has been debated whether EMNEs strengthen or weaken the institutions in host countries they invest in, the literature has paid limited attention to how EMNE investment impacts corruption in other emerging markets, one of the most significant destinations of EMNEs. Following Hoskisson et al. (2013), we categorize two types of emerging markets as targets of EMNE investment, a) low-income emerging markets and b) middle-income emerging markets, based on their institutional and market development. Building on the theory of firm-specific advantages (FSAs) and the institutional advantage (IA) of EMNEs, we reason that EMNEs enter foreign markets in accordance to where their skills and competencies can be effectively utilized, and this impacts corruption in the host country. We make two key arguments: (1) EMNEs predominantly use their IA in low-income emerging markets, which in the long term increases corruption in the host market, and (2) EMNEs predominantly use their FSAs to gain competitive advantage in middle-income emerging markets, which decreases corruption in the host market. Empirical analysis of Chinese outward FDI from the 2008-2018 period supports our hypotheses. Our research contributes to both the literature on EMNEs and corruption.     

认知FrFT域通信系统及其抗干扰性能分析

为了增强无线通信系统的抗干扰能力,设计了一种认知FrFT(分数傅里叶变换)域通信系统（ CFrFTDCS ）,在变换域通信系统中采用分数傅里叶变换,并与认知无线电技术结合,给出了系统的结 构框图和工作原理,分析了系统的抗干扰性能。计算机仿真结果表明,CFrFTDCS具有较强的 抗 干扰能力,针对单音干扰、窄带干扰和Chirp干扰,CFrFTDCS的平均误码率性能比直接序列 扩频（DSSS）通信系统分别改善了约15.70 dB、13.29 dB和13.79 dB,比传统 的变换域通信系统（TDCS）分别改善了约0.18 dB、0.23 dB和3.63 dB。     

供应链和虚拟企业:比较及转化

供应链管理和虚拟企业是已经在世界范围所采用的概念。这些概念包括一系列管理、组织和技术问题,公司为了提高竞争能力,开拓市场机遇,建立合作联盟。供应链管理是一种集成的管理思想,从战略上整体地整合供应商和顾客。虚拟企业是一种动态的临时组织形式,不同的企业为了开拓商业机遇而通过合作弥补自身竞争力的不足。虽然他们有各自的特点,但是也有共同点。