Ecosystem Productivity and Energy Flow of Three-Hardwood Forest

The main characteristics of energy environment, energy products, primary productivity and basic process ofenergy flow for three-hardwood forest(Juglans mandshurica, Fraxinus mandshurica, and Phellodendron amurense) werestudied. The research was mainly hased on the thcory and method of community energetics, dealing with fixed position,quantitative test and expcrimental analysis. The time-space dynamics of sun-radiation in three-hardwood forest were measured and the energy compartment model was set up. his rescarch work provided a scientitic basis for the exploitation, utilization and management of three-hardtwood forest.

Numerical Simulation of Coupled Molten Steel Flow and Temperature Fields in Compact Strip Production Casting

Based on the casting manufacture practice of steel slabs by CSP technology, the flow and the temperature fields of the funnel mould and the secondary cooling segment were simulated using the commercial code, CFX4. Compared with other physical investigations, the correlative data of the present simulation results are in good agreement with them. Therefore, a more comprehensive survey for metallurgy characteristic of the flow and the temperature fields in CSP continuous casting process can be achieved.

Physical simulation of fluid flow and production performance in extra-low permeability porous media

For extra-low permeability reservoirs, with a permeability of about 0.3×10?3 μm2, fluid flow and production performance in cores were studied. A long core holder with a multi-location piezometric measurement was specially designed. An artificial long core, about 700 mm long and with a cross section of 45mm×45mm, was used. In the experiment, pressure distribution along the core can be measured in real time. Single phase flow in the core was investigated. Different modes of production in long cores were also simulated including natural depletion, water flooding, and advanced water flooding. Through physical simulation, flow parameters were collected and production characteristics in extra-low permeability cores were studied. From experimental results, it can be seen that fluid flow in extra-low permeability cores is different from that in high permeability cores. Transmission of pressure in extra-low permeability cores is very slow, and it needs a long time for the pressure to become stable. The distribution curve of pressure along the core is nonlinear and the production rate in extra-low permeability reservoirs decreases sharply. The development effects of different production modes in extra-low permeability cores were compared with one another. Among the production modes, advanced water flooding has much potential for effective development of extra-low permeability reservoirs. Natural depletion and conventional water flooding can also be used in early production periods. In addition, the countermeasures and some ideas especially for the potential development of extra-low permeability reservoirs are suggested.

Information Flow Scheduling in Concurrent Multi-Product Development Based on DSM

Multi-product collaborative development is adopted widely in manufacturing enterprise, while the present multi-project planning models don＇t take techni- cal/data interactions of multiple products into account. To decrease the influence of technical/data interactions on project progresses, the information flow scheduling models based on the extended DSM is presented. Firstly, infor- mation dependencies are divided into four types： series, parallel, coupling and similar. Secondly, different types of dependencies are expressed as DSM units, and the exten- ded DSM model is brought forward, described as a block matrix. Furthermore, the information flow scheduling methods is proposed, which involves four types of opera- tions, where partitioning and clustering algorithm are modified from DSM for ensuring progress of high-priority project, merging and converting is the specific computation of the extended DSM. Finally, the information flow scheduling of two machine tools development is analyzed with example, and different project priorities correspond to different task sequences and total coordination cost. The proposed methodology provides a detailed instruction for information flow scheduling in multi-product development, with specially concerning technical/data interactions.

Flow体验理论对城郊乡村旅游开发的借鉴和启示——以南京市东郊句容市为例

在乡村振兴大背景下,乡村旅游蓬勃发展,尤其是城郊乡村旅游产品不断丰富,但还存在同质化、旅游者心流体验弱等问题亟待解决。本文以Flow※体验理论为指导,以南京市东郊句容市乡村旅游开发为研究对象,对其现状进行分析,从而提出目前日趋竞争激烈乡村旅游环境下城郊乡村旅游产品开发、创新的应对策略,以期对城郊乡村旅游发展起到指导和借鉴意义。

Empirical Study on the Impact of Rural Labor Force Flow on the Price of Agricultural Products——A Method Based on VEC Model

Based on the research introduction of domestic and foreign scholars,dynamic equilibrium between the rural labor force flow and the price of agricultural product is analyzed by VEC model,according to the data of the rural labor force flow and the price of agricultural products in the years 1990-2007.Chows breakpoint test is used to measure the stage characteristics of the impact of rural labor force flow on the price of agricultural product.Result shows that there is a long-term and stationary relationship between the flow quantity of rural labor force and the price of agricultural product.Rural labor force flow,as an exogenous force,affects the agricultural production,and further influences the price fluctuation of agricultural products.Impact of rural labor force flow on the price of agricultural product is from weak to strong,then grows gradually weaker,and reaches its peak value at the year 1998.With the development of rural society and economy and the market process,rural labor force flow endogenously affects the price of agricultural product,which has periodic characteristics.In order to achieve a dual stabilization of the rural labor force flow and the price of agricultural products,the following countermeasures are put forward:vigorously developing vocational education,increasing the support for agricultural production,and making active employment measures.

基于MOMA的可重入混合流水车间调度问题研究

针对可重入制造系统多具有多品种、大规模、混流生产等特点,构建带批处理机的可重入混合流水车间调度问题(reentrant hybrid flow shop scheduling problem with batch processors,BPRHFSP)模型,提出一种改进的多目标蜉蝣算法(multi-objective mayfly algorithm,MOMA)进行求解。提出了单件加工阶段和批处理阶段的解码规则;设计了基于Logistic混沌映射的反向学习初始化策略、改进的蜉蝣交配和变异策略,提高了算法初始解的质量和局部搜索能力;根据编码规则设计了基于变邻域下降搜索的蜉蝣运动策略,优化了种群方向。通过对不同规模大量测试算例的仿真实验,验证了MOMA相比传统算法求解BP-RHFSP更具有效性和优越性。所提出的模型能够反映生产的基础特征,达到减少最大完工时间、机器负载和碳排放的目的。

相变:生产方式如何塑造财产规则

当前关于数字时代财产权利的讨论持续不断,基本上可以分为两种类型:一种是针对较为具体的虚拟物品(如信息内容、游戏装备、账号、数据、虚拟币等),在特定场景中沿着既有法律框架或概念进行分析;一种则试图在原理上阐明数字时代究竟何种对象能够适用财产规则进行更好的保护,以及这种财产规则的构成要件为何,如按照“权利束”或“模块化”框架加以应用。有必要转换角度提问,即成熟的财产权利制度出现,不是因为法律研究主张为何种事物或利益赋予财产权就能自动实现,而是赋权的外部环境成熟了,才会催生相关利益主体提出主张,并推动相关利益在法律上得到确认和保护。违背生产秩序的产权结构和财产规则不可能出现在数字时代,在生产方式进行巨大调整时,财产规则和其他部门法律规则一样,都面临着双重历史任务:一是“破”,即挑战并打破传统制度,允许要素超越既有生产过程低成本流动;一是“立”,即根据生产方式要求树立反映特殊性的新制度,重新商定哪些要素和利益允许参与者继续占有和使用,划定边界。

孔内空气间隔对有/无金属罩聚能装药定向侵彻效果的影响

为了探究孔内径向空气间隔对有/无金属罩聚能装药定向侵彻效果和炸药爆轰能量传递过程的影响,采用ANSYS/LS-DYNA软件,开展孔内装药空气间隔为6,8,10,12,14 cm时的数值模拟研究,分析了聚能装药中有药型罩形成EFP和无药型罩形成聚能气流的能量集中释放过程,以及对孔壁的定向侵彻深度。结果表明空气间隔小于10 cm时,聚能气流对孔壁的侵彻深度相对于EFP平均侵深分别提高了53%(6 cm)和29%(8 cm)。空气间隔大于10 cm时,EFP平均侵彻深度相比于聚能气流均增加了26%(12 cm和14 cm)。计算聚能轴线上EFP和聚能气流单位面积通过孔壁的动能,发现空气间隔较小时,聚能气流在空气中衰减耗散的能量小于EFP塑性变形耗能,此时聚能气流对孔壁的侵彻效果较优;空气间隔较大时,爆轰产物空间膨胀造成聚能气流轴线处的密度和动能显著降低,而EFP由于具有高密度和不可压缩性,能量分散小,动能衰减缓慢,此时EFP对孔壁的侵彻效果优于聚能气流。

基于Moldflow的盒型产品的变形优化与机理探究

纤维增强复合材料类的盒型产品在注塑成型中经常存在变形问题,运用Moldflow软件进行模流分析,不仅得到其变形结果与实际注塑成型的变形趋势一致,还输出了减小这种变形的优化方案,成功地解决盒型产品在实际注塑过程中的变形问题。通过对纤维取向分布的研究,设计对比方案,得到了造成该盒型产品内凹变形的根本原因是盒型产品侧面上的强纤维取向,并深层次地从熔体流动层面阐述了不同纤维取向排布的原因,最终得到了在开模前期即可优化纤维增强材料成型盒型产品变形的方法,对该类产品的变形优化具有重要的指导意义。

Evaluation of Corrosion Product Activity in a Typical PWR with Extended Cycles and Flow Rate Perturbations

Effect of flow rate perturbations has been studied using the modified computer program CPAIR-P for time dependent corrosion rates in Pressurized Water Reactors (PWRs) having extended cycles. In these simulations, a decrease in the corresponding saturation values of corrosion product activity (CPA) is observed for higher pH values. Comparison of CPA’s behavior has been done for constant flow-rate case as well as for transients with elevated 10B levels (~40%) in dissolved boric acid in coolant in two operating cycles. When the flow rate is decreased in the first cycle, the saturation value of CPA attains new higher values. Also, in the second operating cycle, the saturation values are about 12% higher when compared with the values in the first cycle.

气井高速非达西效应主控因素分析

气藏开发实践表明,高速非达西效应对气井产能有着重要影响,不同的气藏,高速非达西效应的影响程度是不同的。对于地层压力较低的气藏,当气井产量较高时,高速非达西效应表现比较强;而对于地层压力较高的气藏,相同的气井产量,高速非达西效应可能并不强。其原因在于气体在较高的地层压力下压缩程度很强,密度、黏度更大,天然气的渗流速度更低,高速非达西效应更弱。根据气井产能方程和雷诺数方程,从气井产量、储层物性和气体性质等方面对影响非达西效应的主要因素进行了敏感性研究,基于临界雷诺数得到了达西和非达西渗流界限,建立了天然气达西渗流图版。通过该图版,可以明确非达西效应的强弱,进而为确定气井配产上限提供指导。

华南陆缘火成岩区差异性地壳热结构及地热意义

高产热花岗岩是重要的壳内热源之一,我国华南陆缘花岗岩体分布广泛,为该区浅表热量的生成及聚集提供了可能。本文在简述区内花岗岩资源分布的基础上,系统分析了区内主要花岗岩体的放射性生热特征,并结合区内近些年施工的地热勘探深钻,对重点地热勘查区的深部地温场分布、地热通量、地壳热结构等进行了对比分析,提出了华南陆缘浅表地热资源的聚热模式。分析认为,华南陆缘地区具有“幔源供热-壳内生热-断裂传热-盖层保热”的四元聚热模式,其中,花岗岩体的放射性生热率是影响区内浅部地温场的主要因素之一,粤北—赣南岩体的生热率明显高于漳州地区的花岗岩体,其近似“热壳冷幔”型或“温壳温幔”型岩石圈热结构与漳州“热幔冷壳”型岩石圈热结构有一定的差异;断裂构造及盖层条件对于地下热量聚集及散失具有明显的控制作用。研究成果对于深入理解华南陆缘地热资源的成因、控热因素,以及今后该地区地热资源勘探开发实践具有一定的理论与指导意义。

宝钢13Cr油套管一贯制技术进展

目前宝钢已建成13Cr油套管从炼钢到螺纹加工的全流程生产体制。介绍了宝钢13Cr炼钢连铸技术、轧制技术、热处理技术、探伤技术、螺纹加工技术等方面取得的进步,从钢水到螺纹的一贯制技术能力得到了大幅度提升,有力地支撑了我国高温高压油气井、深水油气井及储气库井的顺利开发。

基于产量损失率的气井合理配产方法研究

合理配产对气井生产具有非常重要的作用。现有的配产方法一般是按照无阻流量的1/6∼1/3来进行。在研究气体在地层中的非达西效应的基础上,提出了产量损失率的概念,通过量化非达西效应造成的产量损失,建立了气井产量损失率与无因次产量的图版。对于每一个配产,可得到与其相应的产量损失率,非达西效应对气井产量的影响就有了定量化的表征。因此,可根据产量损失率来进行合理配产。对于某些高压气藏,由于地层压力高,气体压缩程度大,地层条件下非达西效应并不强,产量损失率比较低,这类气井就可以将产量配高一些。该配产方法可实现量化储层气体非达西渗流损失,实现气井合理配产。该研究成果能在气井常规配产方法的基础上,进一步优化气井配产制度,更好地满足气井长期稳产、高效开发的需求,为气藏开发提供有益的借鉴。

面向钣金混流生产线的仿真优化研究

文章以某电梯钣金加工公司的钣金混流生产线为背景,通过虚拟仿真方法对钣金生产环节中的投产序列和瓶颈问题进行优化。首先,根据某电梯门板生产线的实际生产状况,建立生产线的仿真模型,以工件完工时间、设备空闲时间和设备总切换时间为目标,基于遗传算法,优化钣金混流生产线的投产序列;其次,通过分析缓存区添加位置和容量对钣金生产线产量的影响,解决生产线堵塞、利用率不平衡等问题。结果表明,对生产线的优化有效,经优化后的投产序列相比原始投产序列整体时间缩短约15%,通过适宜的缓存区设置,各工位设备平均利用率提高了9.6%,产量提高了14.15%。

Numerical Simulation of Oil and Gas Two-Phase Flow in Deep Condensate Gas Reservoirs in Bohai Buried Hills

The BZ19-6 gas field is characterized by high temperature and high pressure (HTHP), high condensate content, little difference between the formation pressure and dew point pressure, and large amount of reverse condensate liquid. During the early stage of depletion development, the production gas-oil ratio (GOR) and production capacity remain relatively stable, which is inconsistent with the conventional reverse condensate seepage law. In view of the static and dynamic conflict in development and production, indoor high-temperature and high-pressure PVT experiment was carried out to reveal the mist-like condensation phenomenon of fluids in the BZ19-6 formation. And the seepage characteristics of condensate gas reservoirs with various degrees of depletion under the condition of HTHP were analyzed based on production performance. The change rule of fluid phase state was analyzed in response to the characterization difficulties of the seepage mechanism. The fluid state was described using the miscible mechanism. And the interphase permeability interpolation coefficient was introduced based on interfacial tension. By doing so, the accurate characterization of the “single-phase flow of condensate gas-near-miscible mist-like quasi single-phase flow-oil-gas two-phase flow” during the development process was achieved. Then the accurate fitting of key indicators for oilfield development was completed, and the distribution law of formation pressure and the law of condensate oil precipitation under different reservoir conditions are obtained. Based on research results, the regulation strategy of variable flow rate production was developed. Currently, the work system has been optimized for 11 wells, achieving a “zero increase” in the GOS of the gas field and an annual oil increase of 22,000 cubic meters.

流程型生产安全数据流的多Agent节点协同分流优化方法

为实现流程型生产安全监测系统的及时、准确决策,结合数据流采集与隐患识别过程,分析非关键数据的冗余、关键数据的缺失和数据计算时延较大的问题,提出基于多Agent的流程型生产安全数据流网络分流调度规划方法和节点流量划分识别机制。研究结果表明:相较于分簇传输方法,数据流网络分流调度方法可以实现关键隐患数据更高的传输成功率;相较于常规的复杂事件处理方法,本文提出的流量划分识别机制在2种类型数据集上实现隐患事件识别均有更低的计算时延。研究结果可为流程行业安全生产数字化管控模式和数据高质量获取提供参考。

流程工业一体化安全管控探讨

化工、冶金、石化、钢铁、造纸、电力等流程工业是国家经济社会发展的重要支柱,其安全高效生产具有重要的战略意义。流程工业生产过程工艺繁多、流程长、工序关联耦合,从原料到产品涉及诸多物理化学变化、物质转移转化和能量转换转移等多源、多尺度与多时空因素的交互作用,影响生产安全、物效能效与生态环境。如何实现流程工业一体化安全管控,是一个长期存在又不断变化的问题。一体化安全管控困难的本质在于物质流能量流到数字流的映射、数字流到高质量信息流的转化、信息流到控制流的转换等问题。探讨如何突破物质流、能量流到数字流映射过程的数字化鸿沟,突破数字流到高质量信息流转变的数智化壁垒、信息流到控制流转换的数滞化障碍,保障物质流能量流不失控、数字流信息流不失真、控制流不失误,提出了流程工业一体化安全管控的“五流三化三不”新思路,以期为流程工业一体化安全管控提供新的框架体系基础,促进流程工业的可持续发展。

基于生产数据的混合流水车间动态调度方法研究

在智能制造背景下,物联网等信息技术为制造系统积累了大量数据,同时人工智能等先进方法为车间数据分析和实时控制提供了有效手段。因此,针对不相关并行机混合流水车间调度问题,提出了一种基于生产数据的动态调度方法,以实现订单完工时间最小化。首先以高质量调度方案为基础,从中提取生产特征和调度规则完成样本构建。其次使用Relief F算法过滤冗余生产特征,获得用于训练和预测的调度样本。然后采用融合鲸鱼优化算法的概率神经网络作为调度模型,实现基于调度样本的训练和预测过程。最后,实验结果表明,所提方法具有良好的特征选择能力和较高的预测精度,与其他实时调度方法相比具有更加优越的性能,可以有效地根据车间实时状态指导制造执行过程。