Identification, evolution and geological indications of solid bitumen in shales: A case study of the first member of Cretaceous Qingshankou Formation in Songliao Basin, NE China

On the basis of sorting out current understanding of solid bitumen (SB) in shales and taking organic-rich shales in the first member of the Cretaceous Qingshankou Formation in the Songliao Basin as an example, the definition, classification, occurrence and evolution path of SB are systemtically studied, and the indicative significance of SB reflectance (Rob) on maturity and its influence on the development of reservoir space are discussed and summarized. The results show that the difference of primary maceral types is primarily responsible for the different evolution paths of SB. Most of the pre-oil bitumen is in-situ SB with only a small amount being of migrated SB, while most of the post-oil bitumen and pyrobitumen are migrated SB. From the immature to early oil maturity stage, bituminite, vitrinite, and inertinite can be distinguished from SB based on their optical characteristics under reflected light, and alginite can be differentiated from SB by their fluorescence characteristics. Under scanning electron microscope, in-situ SB and migrated SB can be effectively identified. Rob increases linearly with increasing vitrinite reflectance (Ro), as a result of a decrease of aliphatic structure and the enhancement of aromatization of SB. Within the oil window three types of secondary pores may develop in SB, including modified mineral pores, devolatilization cracks and bubble holes. At a high maturity stage spongy pores may develop in pyrobitumen. Scanning electron microscopy combined with in-situ SEM-Raman spectroscopy can further reveal the structral information of different types of SB, thus providing crucial data for understanding for understanding OM migration paths, dynamics, and distances at micro-scale.

Optimization of air quantity regulation in mine ventilation networks using the improved differential evolution algorithm and critical path method

In mine ventilation networks, the reasonable airflow distribution is very important for the production safety and economy. Three basic problems of the natural, full-controlled and semi-controlled splitting were reviewed in the paper. Aiming at the high difficulty semi-controlled splitting problem, the general nonlinear multi-objectives optimization mathematical model with constraints was established based on the theory of mine ventilation networks. A new algorithm, which combined the improved differential evaluation and the critical path method(CPM) based on the multivariable separate solution strategy,was put forward to search for the global optimal solution more efficiently. In each step of evolution,the feasible solutions of air quantity distribution are firstly produced by the improved differential evolution algorithm, and then the optimal solutions of regulator pressure drop are obtained by the CPM.Through finite steps iterations, the optimal solution can be given. In this new algorithm, the population of feasible solutions were sorted and grouped for enhancing the global search ability and the individuals in general group were randomly initialized for keeping diversity. Meanwhile, the individual neighborhood in the fine group which may be closely to the optimal solutions were searched locally and slightly for achieving a balance between global searching and local searching, thus improving the convergence rate. The computer program was developed based on this method. Finally, the two ventilation networks with single-fan and multi-fans were solved. The results show that this algorithm has advantages of high effectiveness, fast convergence, good robustness and flexibility. This computer program could be used to solve large-scale generalized ventilation networks optimization problem in the future.

Cooperative co-evolution based distributed path planning of multiple mobile robots

This paper proposes novel multiple-mobile-robot collision avoidance path planning based on cooperative co-evolution,which can be executed fully distributed and in parallel. A real valued co-evolutionary algorithm is developed to coordinate the movement of multiple robots in 2D world, avoiding C-space or grid net searching. The collision avoidance is achieved by cooperatively co-evolving segments of paths and the time interval to pass them. Methods for constraint handling, which are developed for evolutionary algorithm, make the path planning easier. The effectiveness of the algorithm is demonstrated on a number of 2Dpath planning problems.

An eikonal equation based path planning method using polygon decomposition and curve evolution

Path planning is a key technique of autonomous navigation for robots,and the velocity field is an important part.Constructing velocity field in a complex workspace is still challenging.In this paper,an inner normal guided segmentation algorithm in a complex polygon is proposed to decompose the complex workspace in this paper.The artificial potential field model based on probability theory is then used to calculate the potential field of the decomposed workspace,and the velocity field is obtained by utilizing the potential field of this workspace.Path optimization is implemented by curve evolution,during which the internal force generated in the smoothing process of the initial path by a mean filter and the external force is obtained from the gradient of the workspace potential field.The parameter selection principle is deduced by analyzing the influence of several parameters on the path length and smoothness.Simulation results show that the designed polygon decomposition algorithm can effectively segment complex workspace and that the path optimization algorithm can shorten and smoothen paths.

The Effect of Spatial Structure Character of Heat Source on the Ray Path and the Evolution of Wave Energy of Meridional Wave Train

This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional linear variation the rays of quasi-stationary planetary wave may propagate along oblique lines and if the meridional variability of heat source has second order term the rays show distinct deformation as a great circular route. Additionally, the inhomogeneous distribution may cause lower frequency oscillations in mid- and low-latitudes. The combination of zonal and meridional wave numbers and distributive character of heat source may form an inverse mechanism of variational trend of generized wave energy, reflecting in some degree the physical process of transition between meridional and zonal flow patterns.

Expansion Strategies and Evolution Paths of Hotel Groups in China

The organizational structure change of enterprises should be subject to the change of strategy,and strategy change is the reaction to the environment change.This paper studied the expansion strategies and evolution paths of hotel groups in China by a survey in 2007,in which the research objects were 91 hotel groups listed by China Tourist Hotels Association.The conclusions are drawn:based on the two dimensions of unification management function scope and the unification management degree,hotel groups can be divided into four strategic types,including strategically concentrated group,close function group,widespread alliance group and loose union group.Simultaneously there are three different expansion paths:stability path,growth path and undulation path.About 72.5% of Chinese hotel groups have a stability or growth expansion path.

Multi-path planning algorithm based on fitness sharing and species evolution

A new algorithm is proposed for underwater vehicles multi-path planning. This algorithm is based on fitness sharing genetic algorithm, clustering and evolution of multiple populations, which can keep the diversity of the solution path, and decrease the operating time because of the independent evolution of each subpopulation. The multi-path planning algorithm is demonstrated by a number of two-dimensional path planning problems. The results show that the multi-path planning algorithm has the following characteristics: high searching capability, rapid convergence and high reliability.

Analysis on the Evolution Path of Transformation of Manufacturing Enterprises through Servitization——A Case Study Based on ShaanGu Group

Service-oriented manufacturing is an emerging innovative development model,and its core is the deep integration of products and services.It has become a hot issue in current research.In order to deeply explore the evolution path of servitization transformation of manufacturing enterprises,ShaanGu Group is taken as a case,and discusses practical application of service-oriented manufacturing model in different development processes of ShaanGu Group.Thus,four stages of transformation of ShaanGu Group through servitization are summarized:specialized after-sales service stage,rental service stage,engineering complete service stage and financial service stage.Through comparative research,it is found that general evolution path of manufacturing enterprises to service transformation is:the primary stage(providing product-oriented product service system)→the intermediate stage(providing application-oriented product service system)→the advanced stage(providing utility-oriented product service system)→the completed stage(providing pure service).On this basis,some suggestions are provided for manufacturing enterprises to integrate productive services in the process of transformation.

Three-dimensional Analysis of the Evolution Path of Teaching Methods in China--Reflection and Prospect of Information-based Teaching

Under the influence of the information technology revolution,the teaching method,as the way to impart teaching content or the means to realize teaching content,has undergone a process of constant evolution and transformation.This transformation is still ongoing.In order to explain this phenomenon,we establish a three-dimension analysis framework of"ECONOMIC BASE-INFORMATION TECHNOLOGY-CULTURE".All kinds of logics involved in them are closely linked,thus influencing each other.At the same time,these aspects constantly affect the historical trajectory of the evolution.Based on the above analysis framework,the paper uses the historical approach to expound the evolution path on teaching methods in China since ancient times and divides it into four stages.Combined with the practical problems and interview results,we rethink the present information teaching methods.In the end,some suggestions are put forward in order to promote the further development of education-related fields.

Probability Distribution of Average Length of Node Path and Its Evolution Trace of Aviation Network of China Based on Complex Network

In order to reveal the complex network feature and its evolution principle of aviation network of China,probability distribution and its evolution trace of average length of node path of aviation network of China were researched according to statistics data in years 1988,1994,2001,2008 and 2015 of civil aviation of China.Floyd algorithm to calculate the path length between any two nodes of network was applied and average length of node path of aviation network was obtained according to this algorithm.It was discovered that average length of node path to other nodes had normal distribution function in each year.At meantime,the location parameter and scale parameter of normal distribution function had linear evolution trace.Airline rate was an index to describe the density of airline.It was found that average length of node path of aviation network of China evolved synchronously with airline rate and they had linear relationship.

基于P-TRM的中国稀土产业技术创新的政策演化路径研究

稀土被称为“工业维生素”,已成为全球各国资源争夺和技术竞争的焦点。我国是稀土资源大国,政府高度重视稀土产业技术的创新,出台了系列创新政策以推动中国从稀土大国向稀土强国转变。收集1978—2021年国家层面颁布的63份与稀土产业相关的创新政策文本,结合内容分析法,构建政策-技术路线图(P-TRM)分析框架,剖析稀土产业技术创新的政策演化历程与路径。研究发现:从创新政策工具来看,稀土产业创新政策工具呈现出进入阶段以结构型创新政策工具为主,到逐步追赶阶段结构型与功能型创新政策工具同时发力,再到跨越阶段由功能型创新政策工具占据主导的演进趋势;从政策作用技术环节来看,从进入阶段主要发力于原材料制备技术,到逐步追赶阶段聚焦关键部件加工和终端产品制造技术,最后跨越阶段延伸到废弃产品循环利用技术,呈现出从关注单一技术环节到全技术链的演进趋势;从政策演化路径来看,稀土产业创新政策随着稀土产业创新生态的演变而变化,不断完善稀土产业创新生态系统,促进稀土全产业链技术的创新。最后,针对中国稀土产业技术创新政策的优化提出政策建议。

Spinel + quartz-bearing ultrahigh-temperature granulites from Xumayao,Inner Mongolia Suture Zone,North China Craton:Petrology,phase equilibria and counterclockwise p-T path

The Khondalite Belt within the Inner Mongolia Suture Zone （IMSZ） in the North China Craton is a classic example for Paleoproterozoic ultrahigh-temperature （UHT） metamorphism. Here we report new spinel-bearing metapelitic granulites from a new locality at Xumayao within the southern domain of the IMSZ. Petrological studies and thermodynamic modeling of the spinel -- quartz-bearing assemblage shows that these rocks experienced extreme metamorphism at UHT conditions. Spinel occurs in two textural settings：（1） high Xzn（Zn/（Mg ＋ FeH -- Zn） = 0.071--0.232） spinel with perthitic K-feld- spar, sillimanite and quartz in the rock matrix; and （2）low Xzn （0.045-0.070） spinel as inclusions within garnet porphyroblasts in association with quartz and sillimanite. Our phase equilibria modeling indicates two main stages during the metamorphic evolution of these rocks：（l） near-isobaric cooling from 975 ℃ to 875 ℃ around 8 kbar, represented by the formation of garnet porphyroblasts from spinel and quartz; and（2）cooling and decompression from 850 ℃, 8 kbar to below 750 ℃- 6.5 kbar, represented by the break-down of garnet. The spinel ＋ quartz assemblage is considered to have been stable at peak metamorphism, formed through the break-down of cordierite, indi- caring a near isothermal compression process. Our study confirms the regional extent of UHT metamor- phism within the IMSZ associated with the Paleoproterozoic subduction-collision process.

Analyzing Industrial Structure Evolution of Old Industrial Cities Using Evolutionary Resilience Theory：A Case Study in Shenyang of China

The recession and revitalization of old industrial cities concerns urban industrial evolution and its characteristics. Based on the theory of evolutionary resilience, we developed an analytical framework for the industrial structure evolution of old industrial cities, and applied the framework to a case study in Shenyang. The following conclusions are drawn. First, since 1978, Shenyang's industrial growth capacity has shown fluctuation between ‘contraction-expansion'. As the secondary industry has a much stronger expansionary and contractionary capacity for growth, this results in lacking stability leading to industrial structure transformation. Second, since 1999, the orientation towards a high-end manufacturing industry in Shenyang has weakened, and the evolution of the new and old growth path is characterized by low-end orientation. Third, since 2007, Shenyang's industrial innovation output capacity has dropped sharply which has been significantly affected by scientific and technological personnel and enterprise-owed science and technology institutions and to a less extent by R&D expenditure. We applied the resilience theory to study the industrial evolution of an old industrial city, explored new study perspectives on industrial evolution and verified the applicability of the resilience theory. This paper provides a scientific reference for understanding the recent deceleration in economic growth in the Northeast old industrial base, and for exploring new paths toward revitalization.

Texture Evolution Induced by Deformation in Aluminum Alloy

The lower formability of aluminum alloy sheets is the inherent characteristic of the material. During material forming processes the material undergoes a complex strain history. In this paper, the effect of crystallographic texture induced by deformation in aluminum sheet is studied. The transformation of crystallographic textures induced by uniaxial tensile, cup drawing and bulge tests was measured through X-ray diffraction and analyzed. The author studied the texture evolution rule under different strain paths. A qualitative relationship between the deformation and texture evolution has been founded.

P-T path of metamorphism and U-Pb monazite and zircon age of the Kitoy terrane: Implication for Neoarchean collision in SW Siberian Craton

The first data on P-T metamorphic conditions coupled with U-Pb monazite and zircon age obtained for the Neoarchean Kitoy granulite-gneiss terrane(SW Siberian Craton).Alumina gneisses of the Kitoy terrane indicate two-staged metamorphic evolution.The first stage of regional metamorphism(M1)occurred at high-amphibolite facies conditions at T=780-800℃ and P=8-9 kbar.The second stage(M2)belongs to MT-HT/LP type of metamorphism with the wide temperature interval 600-750℃ and pressure 2-4 kbar.Two age peaks were established on the basis of U-Pb monazite and zircon dating in garnet-anthophyllite gneisses.Both of them correspond to the Neoarchean age:the age of M1 falls into the interval of ca.2489-2496 Ma,the age of M2-ca.2446-2456 Ma.The high-temperature metamorphism of the Kitoy block and nearly coeval granitoid magmatism can be an evidence for the Neoarchean collision in SW Siberian craton.

Pressure-temperature Evolution of the Metapelites in the Motuo Area, the Eastern Himalayan Syntaxis

The Motuo area is located in the east of the Eastern Himalayan Syntaxis.There outcrops a sequence of high-grade metamorphic rocks,such as metapelites.Petrology and mineralogy data suggest that these rocks have experienced three stages of metamorphism.The prograde metamorphic mineral assemblages （M1） are mineral inclusions （biotite ＋ plagioclase ＋ quartz ± sillimanite ± Fe-Ti oxides） preserved in garnet porphyroblasts,and the peak metamorphic assemblages （M2） are represented by garnet with the lowest Xsps values and the lowest XFe# ratios and the matrix minerals （plagioclase ＋ quartz ± K-feldspar ＋ biotite ＋ muscovite ＋ kyanite ± siilimanite）,whereas the retrograde assemblages （M3） are composed of biotite ＋ plagioclase ＋ quartz symplectites rimming the garnet porphyroblasts.Thermobarometric computation shows that the metamorphic conditions are 562-714℃ at 7.3-7.4 kbar for the M1 stage,661-800℃ at 9.4-11.6 kbar for the M2 stage,and 579-713℃ at 5.5-6.6 kbar for the M3 stage.These rocks are deciphered to have undergone metamorphism characterized by clockwise P-T paths involving nearly isothermal decompression （ITD） segments,which is inferred to be related to the collision of the India and Eurasia plates.

Integrated P-T Paths of the High-Pressure Rocks and Their Tectonic Implications for the Mountain-Building of the North Qilian, China

After the integration of petrographic study, geothermobarometry and Gibbs method, the synthetic P-T paths for the rocks from different geological profiles in the North Qilian, China, have been derived. The composite P-T paths from different methods indicate that all the high-pressure rocks in the Qilian area recorded P-T paths with clockwise loops starting at the blueschist facies, later reaching peak metamorphism at the blueschist facies, eclogite fades or epidote-amphibolite facies and ending up with the greenschist facies. The incremental Ar-Ar dating shows that the plateau ages for the high-pressure rocks range from 410 to 443 Ma. The plateau ages could be used as a minimum age constraint for the subduction that resulted in the formation of these high-pressure rocks in the Qilian area. It is proposed that the late-stage decompressional and cooling P-T paths with ends at the greenschist facies for these high-pressure rocks probably reflect the uplift process which could occur after shifting the arc-trench tectonic system to the system of continental orogenic belts. The retrograde paths for the high-pressure rocks in the North Qilian tectonic belt are characterized by dramatic decompression with slight cooling, which suggests very rapid exhumation. Petrography supports that the mountain-building for the Qilian mountain range could undergo a very fast process which caused rapid uplift and denudation.

造山带榴辉岩的变质作用P-T-t轨迹研究进展

板块俯冲和折返是板块构造理论的重要组成部分,也是固体地球科学研究的一个前沿方向。俯冲/碰撞造山带内的高压-超高压变质岩经历了俯冲至地球深部而后折返至地壳浅部的复杂地质过程,反演它们的P-T-t轨迹是高压-超高压变质作用研究的重要课题,也是揭示造山带构造演化的一个重要途径。造山带榴辉岩作为高压-超高压变质岩中的一类典型代表,常保留多个变质阶段的矿物组合,较完整地记录了造山带演化的关键信息,是反演P-T-t轨迹的理想样品。根据详细的岩相学观察和矿物成分分析,能识别出榴辉岩不同变质阶段的矿物组合。在此基础上,选取合适的地质温压计或采用相平衡模拟,可获得岩石相应变质阶段的温压条件(P-T)。如何获得多阶段变质年龄(t)和如何匹配变质作用的温压条件和年龄信息,是反演榴辉岩P-T-t轨迹的两个关键问题。本文针对榴辉岩中的锆石、金红石、榍石和褐帘石这四个适用于U-Pb定年的副矿物,从结晶条件和封闭温度等角度评估它们可能记录的年龄信息。结果表明,受限于结晶的温压条件或结晶后的改造作用,单种矿物定年难以获得多阶段年龄,一些实际研究中需要采用多种矿物或多个同位素体系实施定年分析。对于将副矿物从岩石中分选出来再实施原位微区定年的方法,测定微量元素和包裹体矿物组合并不总能准确限定这些定年副矿物结晶于哪个变质阶段,这将影响副矿物年龄意义的解析。观察分析定年副矿物在榴辉岩中的结构,能够厘清它们与岩石主要组成矿物之间的成因联系,进而可通过主要组成矿物限定副矿物的结晶温压条件和年龄意义。因此,具有岩相学结构制约的副矿物原位定年分析(“岩石年代学”方法)是耦合变质岩石学(P-T)和地质年代学(t)结果的重要手段,应在今后的变质作用研究中得到更多的重视和运用。与此同时,进一步研究变质分解/重结晶、熔/流体交代、脆/韧性变形等地质作用对副矿物定年同位素体系的影响。变质作用的时间信息不仅包括通过同位素定年获得的绝对年龄,也包括变质作用所持续的时间。受制于定年测试的精度,一些短时间尺度(≤1Myr)的变质作用难以通过同位素年代学方法进行限制。基于矿物的成分扩散、结构演变、力学性质转变等模拟方法,可用于揭示和限定这类变质事件的时间尺度,以此精细刻画岩石的变质P-T-t轨迹,有助于深入理解造山带榴辉岩的形成过程和机制。

Anticlockwise P-T Path and Zircon U-Pb Dating of HP Mafic Granulites in Yushugou Granulite-Peridotite Complex, Southern Tianshan Mountains, China

The Yushugou HP granulite-peridotite complex is located at east of northern margin of southern Tianshan mountains,China,which consists of granulite unit and peridotite unit mainly.Because of the rare association of

Evolution of green development pattern in western China

Since the 18 th Party Congress, green and low carbon industry-oriented industrialization road became a new main industry development direction. Through analyzing four kinds of region industry development modes and current situation of the industrial development of the western region, this paper uses DEA method to evaluate 11 western provinces industry green degree and resource utilization degree between 2008 and 2014, and gets the evolution process of the industrial development pattern during 7 years. The results indicate that: industrial development models are not the same in the western China and green degree are generally low. On this basis, it is concluded that the evolution of green development patterns for reference are 4 kinds of industrial development models. Finally, on the basis of green development pattern evolution path this paper provides advice to improve green degree and the degree of resource utilization.