2019年黑龙江省猪肉市场运行情况分析

2018年非洲猪瘟疫情出现以来,全国及黑龙江省生猪生产、猪肉市场受到了较大的影响,生猪、能繁母猪存栏减少,生猪出场价格也经历了明显波动。2019年春节以后,随着省外调出量增加和猪源减少,黑龙江省生猪出场价格进入上升通道,超过了全国平均水平,白条猪肉批发价格和猪肉市场零售价格随之上行。通过对2019年黑龙江省生猪生产环节、屠宰加工环节、猪肉市场零售环节进行调研,对生猪出场价格、白条猪肉批发价格、猪肉零售价格、生猪和能繁母猪产能等指标进行分析,阐述了以生猪和猪肉市场为重点的肉类产销形势,为促进肉类产业高质量发展、提高市场保供能力提供参考。     

煤矿井下主排水系统的设计与实现

针对煤矿井下主排水系统人工就地操作的问题，介绍了一种基于PLC的水泵控制方式，该系统选用PLC为控制核心，通过液位、压力、流量、温度等传感器采集水泵运行参数，对水泵及管路阀门、高压开关等设备进行控制与监测，使设备在无人干涉的情况下实现了多台水泵和关联设备的联动运行和参数采集、状态监测、数据处理、故障报警、报表查询等，使设备达到最佳运行状态，满足了煤矿生产环境及安全生产的需要，提高了煤矿自动化水平，降低了劳动力强度，为实现煤矿数字化矿井打下良好的基础。     

Domestic demand-side response with heat pumps: controls and tariffs

ABSTRACT

Electric heat pumps feature prominently in projected energy transitions in the UK and elsewhere. Owing to their high electricity consumption, heat pumps are viewed as important targets for demand-side response (DSR). Findings are presented from a field trial of a new control system that aims to optimize heat pump performance, including under time-varying tariff conditions. The trial involved monitoring 76 properties with heat pumps, but without dedicated heat storage; 31 of these received the control system. Interviews were conducted with a subsample of 12 participants. The controller successfully evened out electricity demand over the day (reducing the evening peak), but this was associated with increased late night and daytime temperatures. Interview participants reported some disturbance owing to overnight heating and noise, as well as usability issues with the controller interface and hardware. These issues present risks to the future acceptability of such systems. While the system delivered short-term demand reductions successfully, longer-term demand shifting risked causing unacceptable disturbance to occupants. Future control systems could overcome some of the issues identified in this pioneering trial through more effective zoning, using temperature caps or installing dedicated heat storage, but these may either limit the available flexibility or be challenging to achieve.     

冗余驱动闭链弓形五连杆动力学建模与优化

研究了冗余驱动闭链弓形五连杆动态翻滚过程中驱动力矩协调分配的问题。建立了闭链弓形五连杆运动学分析模型，分别对驱动杆件和约束杆件的速度、加速度进行分析，得到各杆件的加速度矩阵和角加速度矩阵，进而得到各杆件的合力及力矩，从而获得该机构的牛顿-欧拉动力学方程。采用伪逆法对各驱动力矩进行协调分配,使瞬时驱动力矩2范数最小。给定机构动态翻滚过程的关节轨迹，分别计算非冗余驱动和冗余驱动方式下的驱动力矩，计算结果表明，冗余驱动方式可以显著减小最大瞬时驱动力矩。     

Testing the oil price efficiency using various measures of long-range dependence

In this paper, we empirically examine the application of a host of techniques employed to measure price efficiency through long-range dependence using prices of monthly oil contracts. Using a series of methods, we analyse the volatility (daily absolute returns) of WTI and Brent oil prices for nine different contracts with maturity, ranging from 1 to 9 months, during the sample period of 1990-2017. We use bootstrapping to compute the confidence interval of the parameter of long-range dependence. Our results indicate that on an average, there is no long-range dependence in the volatility of oil price contracts at least at the 10-percent level of significance. Moreover, our results of rolling estimates suggest that the normality assumption does not affect the results considerably, and the results are robust to different rolling window sizes. While the results of the efficiency index suggest that the efficiency of oil returns vary with time, the futures contracts for Brent oil are found to be less efficient compared to WTI oil. The long-term futures contracts are more efficient than short-term contracts.     

Financial development and energy consumption nexus in emerging economies

This study aims to examine the relationship between financial development, energy price, real income, and energy consumption in 17 emerging economies. In doing so, the financial development has been handled with three different dimensions (banking sector, stock market, and bond market) and the effects of each financial development dimension on energy consumption is investigated. For this purpose, the annual data of 1991–2015 are analyzed using the common correlated effect (CCE) estimator to take into account the cross-sectional dependence. The results show that bond market development is the most efficient dimension to reduce the energy consumption.     

对于完善中国居民用气价格机制的思考

中国天然气产业链已进入快速发展阶段,天然气价格形成机制也随之不断演变和完善,其中居民用气价格在我国则极为敏感。为发挥价格在资源配置中的作用,对中国居民用气价格机制进行了梳理。结果表明:(1)居民用气价格机制是天然气价格市场化改革整体的组成部分之一,2013年6月以前二者基本相互适应,之后则相互脱节,完善、改革的大方向是要使前者适应后者,完善居民用气价格机制有利于推进天然气价格市场化改革;(2)中国天然气价格市场化改革仍将处于中级阶段,目前有谋划高级阶段内容的举措;(3)完善居民用气价格机制是一项长期的任务,耗时估计在10年左右;(4)居民用气价格机制目前面临着一些突出的问题——非居民用气与居民用气价格的"双轨制"、民用气阶梯定价落地制度难以适应气价市场化、居民用气的上游价格多年未调整有可能引发多重矛盾的叠加爆发。完善居民用气价格机制的对策包括:(1)居民用气价格机制要与天然气价格市场化统筹设计,抓好价格联动机制建设;(2)加大居民用气上游价格可变动的制度安排;(3)注意运用"窗口期"机遇,化解居民用气价格"交叉补贴"的历史问题;(4)逐步调整供气调峰代价的承担主体,完善调峰代价分担机制;(5)推动居民用气价格机制改革试点。     

我国如何实行天然气能量计量和计价

我国是世界上为数不多的使用天然气体积计量和计价的国家,在当前我国天然气资源供应多元化、市场需求旺盛、天然气体制和天然气价格改革不断深入、市场化竞争格局正在形成的大环境下,实行天然气能量计量和计价比以往任何时候都更为迫切。为此,在阐述我国实行天然气能量计量计价紧迫性的基础上,分析了我国天然气采用能量计量计价在计量界面、计量方法、计量单位、气价转换和管道运价等方面所面临的问题,并提出了实行天然气能量计量计价的解决办法和实施路径。研究结果表明:(1)我国天然气正进入资源供应多元化和国际化、体制改革不断深化、天然气价格和天然气交易市场化发展的新时期,迫切需要改革我国传统的天然气体积计量计价方式,实行天然气能量计量计价;(2)实行天然气能量计量计价应基于我国天然气能量计量标准体系并结合天然气产业链实际,优选切实可行的能量计量界面和计量方法 ;(3)以焦耳作为能量计量单位,按国家发展和改革委员会指定的天然气热值进行天然气体积价格向能量价格转换;(4)天然气管道运输应统一实行能量计量计价;(5)我国天然气能量计量计价宜在试点先行的基础上,按直供工业用户、非居民用户、居民用户的顺序逐步推进。     

俄罗斯天然气在东北地区的利用发展分析

中俄东线天然气即将引入中国,将对东北地区的天然气利用项目产生有力的推动作用,同时也将面临各种问题。为建立长期可持续发展资源供应体系,结合能源供需实际,讨论了俄气到来后,东北地区天然气未来的发展方向,并分析了存在的主要问题:①天然气自产不足,域外依存度高;②地域特点决定替代能源可有多种选择;③调峰困难且富余天然气难以处理;④天然气替代经济性差,价高难以承受。并针对矛盾点进行了总结,指出来源多元化和资源多样化才能可持续发展。明确东北地区宜以天然气作为过渡能源,并提出了适宜地区经济发展的天然气利用建议。