Testing vertical price transmission for Vietnam's Robusta coffee

Vietnam has undergone market reforms over the last three decades; and as a consequence, the coffee sector has become increasingly market‐driven. The success of the government's liberalisation policies in terms of market efficiency is investigated by examining the transmission of both positive and negative price changes for Robusta coffee between export and farmgate prices. We used a threshold vector error correction model and high‐frequency daily data. The primary result here is that of a symmetric price transmission between export and farm‐level prices. This result holds when tested with weekly price data, derived from the daily data. Farmgate prices respond faster to decreases than increases in export prices when the long‐run deviation exceeds a certain threshold. These price changes are transmitted within several days. This research also confirms the importance of transaction costs, and other price frictions mostly ignored in prior analyses for coffee.     

基于西门子PLC除尘器粉尘防爆危险源信号检测及预警系统的研究

研发适用于滤袋式除尘器粉尘爆炸危险源信号的实时检测及预警系统。该系统综合应用工业控制、PLC控制、智能测控终端无线传输、云平台数据管理等技术。采用传感器分别监测除尘器运行时的进出风口压差、除尘器运行状态、高压脉冲喷吹压力和箱体温度。当监测信号不在系统预设的合理范围时,PLC输出就地预警信号,监测信号也可通过无线传输模块上传到云平台。运用云平台的数据分析功能,实现除尘器运行状态系统化监测和综合管理。     

Bank lending channel in a dual banking system: Why are Islamic banks so responsive?

We examine the interest rate sensitivity of both deposits and credits at Islamic and conventional banks in Turkey. We find that the bank lending channel is especially operative for Islamic banks. Impulse responses for conventional and Islamic banks reveal that Islamic bank depositors’ sensitivity to policy rate changes is substantially larger than that of conventional bank depositors. Next to heavily dependence on deposit funding, we consider that inertia in Islamic bank deposit rates impedes these banks to keep those depositors who consider the opportunity cost of monetary policy rates is unbearable. On the lending side, we obtain similar results, implying that tight monetary policy leads to a larger contraction in Islamic bank credits. This finding is a reflection of the favourable attitude of Islamic banks towards small and medium‐sized enterprise (SME) financing. When similar relationships are analysed for currency and inflation shocks, we again find larger responses for Islamic banks showing the cyclical nature of SME credits.     

进口贸易视域下国际粮价对国内粮价的传导路径--来自玉米和大豆的证据

基于玉米和大豆等粮食国际、国内价格历史数据,运用协整及误差修正模型、脉冲响应函数等方法,揭示国际粮价对国内粮价的传导作用及影响路径。理论分析表明,国际粮价通过进口直接路径、进口产品成本路径和进口替代路径等三个子路径传导至国内粮价。实证检验发现,国际大豆价格进口直接路径和进口产品成本路径传导均比较充分,即国际大豆价格会影响大豆进口价格,进而影响国内大豆价格,最终影响国内豆油价格;国际玉米价格进口直接路径和进口产品成本路径传导则不充分,国际玉米价格会影响玉米进口价格,但是对国内玉米价格和国内玉米淀粉价格影响程度较低;而在进口替代路径中,玉米和大豆的国际价格传导均不充分。我国应继续推进以提质增效为目标的农业供给侧结构性改革,加大粮食生产科技投入力度,调动农民种粮积极性,集中力量提高粮食供给质量和效率;坚持粮食进口仅为调剂国内供求余缺的方针,把握粮食安全的主动权;建立健全粮食市场的价格调控体系及风险防控体系,规避国际粮食市场剧烈波动对国内粮食市场的影响。     

空间信息传输中的多天线技术综述

近年来，空间信息传输中的多天线技术得到了广泛关注和大量研究。首先介绍了多天线技术的信息论基础和演进过程；然后综述了多天线通信和雷达技术的研究进展，包括多输入多输出(Multiple-Input Multiple-Output,MIMO)卫星通信技术、深空天线组阵技术、空间多维协同传输理论与技术、MIMO雷达技术和分布式孔径相参合成雷达技术，分析了其中的关键技术及未来可研究的方向；最后，总结了多天线技术在航天测控领域应用的优势，展望了基于多天线的测控技术。     

中国特色社会主义市场经济货币政策体系的形成及演变*

伴随中国特色社会主义基本经济制度的发展，与之相适应的宏观调控机制不断完善。货币政策体系作为其中重要组成部分，在持续深化改革的进程中逐渐演进，成为构建更加系统完备、更加成熟定型的高水平社会主义市场经济体制的重要内容。在货币政策最终目标及中间目标、货币政策工具、货币政策传导机制等方面正在形成与中国特色社会主义基本经济制度相适应的政策体系，并且具有鲜明的中国特色。本文讨论改革开放以来中国货币政策体系的形成、演变过程及特点。     

Animal disease outbreaks and food market price dynamics: Evidence from regime‐dependent modelling and connected scatterplots

The economic impacts of animal disease outbreaks have been widely discussed in the literature. Most authors have centred their attention on estimating the direct costs. Recent studies have shown that the indirect economic effects might lead to equal or even higher welfare losses. This study aims to contribute to this field of research by assessing the effect of an animal disease outbreak on food market price dynamics in Mexico, accounting for the potential effect of an antitrust intervention. We employ a regime‐dependent vector error correction model and a connected scatterplot analysis. The results show that both the outbreak and the antitrust intervention caused structural breaks in food market price dynamics between producers and consumers, reflected in an increase in the absolute component of the marketing margin, with serious food security implications.     

Information transmission between large shareholders and stock volatility

Does information transmission between large shareholders exacerbate stock volatility or reduce stock volatility? In this study, based on the common shareholding data in the Chinese stock market from 2007 to 2017, we establish the shareholder’s coshareholding network, and use the weighted network clustering coefficient to measure the information transmission speed. Moreover, we investigate the impact of information transmission speed on stock volatility. The empirical results show that a nonlinear U-shaped relationship exists between information transmission speed and stock volatility. The findings are robust to the inclusion of other determinants of stock volatility identified in the literature. Finally, we verify the existence of private information interaction in the coshareholding network.     

华北油田冀中电网输配电线路存在的主要问题及应对措施

本文论述了华北油田冀中电网输电线路存在的老化、线路下方违章建筑物、树木顶线、杆塔缺土、施工车辆、挖掘机、吊车误碰导线跳闸等情况,并提出了应对措施。