Experimental study on the interrelation of multiple mechanical parameters in overburden rock caving process during coal mining in longwall panel

In order to comprehend the dynamic disaster mechanism induced by overburden rock caving during the advancement of a coal mining face, a physical simulation model is constructed basing on the geological condition of the 21221 mining face at Qianqiu coal mine in Henan Province, China. This study established, a comprehensive monitoring system to investigate the interrelations and evolutionary characteristics among multiple mechanical parameters, including mining-induced stress, displacement, temperature, and acoustic emission events during overburden rock caving. It is suggested that, despite the uniformity of the overburden rock caving interval, the main characteristic of overburden rock lies in its uneven caving strength. The mining-induced stress exhibits a reasonable interrelation with the displacement, temperature, and acoustic emission events of the rock strata. With the advancement of the coal seam, the mining-induced stress undergoes four successive stages: gentle stability, gradual accumulation, high-level mutation, and a return to stability. The variations in other mechanical parameters does not synchronize with the signifcant changes in mining-induced stress. Before the collapse of overburden rock occurs, rock strata temperature increment decreases and the acoustic emission ringing counts surges with the increase of rock strata displacement and mining-induced stress. Therefore, the collaborative characteristics of mining-induced stress, displacement, temperature, and acoustic emission ringing counts can be identifed as the precursor information or overburden rock caving. These results are in good consistent with on-site situation in the coal mine.

ON EVOLUTION OF MAN-LAND SYSTEM IN OASIS-Taking Minqin Basin as a Case

Human beings have had a tremendous i mpact on natural ecosystems and are n ow the principal power to change the biosphere.It is logical t hat we should pay close attention to t he interaction between human system s and environ-mental systems.Taking Minqin basin,Gansu Province,as a case,this paper focuses on the evolution of regional physi-cal environments and the cultural sy stems by which people maintain their relationships with those environme nts.This pa-per presents the conceptual framewo rk for the man-land system.Expectin g to accelerate the regional sustain able develop-ment,it also analyses the evolution ary mechanism of regional man-land s ystem.On the basis of reviewing and a nalyzing the evolution of man-land system in Minqin basin,the paper also brings fo rward an adjusting mode for the studi ed area,which consists of three aspects:to b uild up a concept that economic growt h must harmonize with environmental quality’s and land productivity’s improvemen t;to make a whole planning and management in the drainage area;and to push for-ward the technique of water-saving i rrigation and establish water-saving agricultural system.It’s meanin gful for resource exploitation and sustainable development of Chinese northwestern arid area,which is represented by Minqin basin,by under-standing what great changes the basin has experienced and is experiencin g at the global background,and studying its time order and territorial structure,th e system’s character and law of evolu tion,trend and the regulating ways t o improve man-land relationship.

Grey Interrelation Analysis for the Use of Rare Earths and the Elements in Soil in Growing Cotton

The method of grey interrelation analysis is adopted for the analysis of the relationship between the amount of rare earths applied and the factors of the soil in increasing cotton production in Kazuo County, Liaoning Province. The results show that there is an intimate relation between the use of the RE and the elements in the soil. The pH value, total K, and total P are the main factors influencing the relation, and the total N, hydrolytable N, organic matter, K2O and P2O5 are the secondary factors. This provides a scientific basis for the use of the RE.

Interrelation among several important links in seismic risk analysis

In order to further reveal the interrelation among division of seismic statistical regions, delimitation of potential seismic sources and estimation of seismicity parameters, we select 21 representative sites located in different places within the range of 100°-120°E, 29°-42°N to study the influences of seismicity parameter uncertainties of statistical regions on seismic risk estimations of these sites in the inhomogeneous and homogeneous distribution models. Combining the results from this study and previous ones, we can see that different schemes for dividing seismic statistical regions can change the seismic data in a statistical region. The uncertain data and additional uncertainty in selecting time intervals for seismic statistics will result in uncertainty of seismicity parameters estimation in a statistical region. For the homogeneous model, the larger the variation of this uncertainty is, the greater the uncertain influence on the seismic risk estimation of a site will be, which means that the division of seismic statistical regions makes a major contribution. In a seismic statistical region, the delimitation of potential sources and variant weight assignment of spatial distribution functions can raise the estimated values of ground motion parameters in the place where great earthquake might occur and its vicinity. In these places, the influence of uncertainty in potential source delimitation is very obvious, especially on the absolute magnitude of ground motion parameters （e.g., intensity）, which means that the link of potential source delimitation makes a major effect. Generally speaking, the link of potential source delimitation affects mainly the sites located in the potential sources with the highest and second-high upper-limit earthquake magnitudes or in the vicinity of those with the highest upper-limit magnitude. While for the sites located in the potential sources with low upper-imit magnitudes, the uncertainty influence of statistical region division is larger than that of potential source delimitation.

Development of Qinba Mountainous Area in the Historical Period from the Perspective of Man-Land Relationship

Taking agricultural development as the starting point,this paper explored the dynamic mechanism and implementation path of agricultural development in Qinba Mountainous Area from the perspective of man-land relationship. It found the regular understanding of ecological changes in Qinba Mountains. It is a comprehensive review and exploration on agricultural development and environmental evolution,and aims to provide a historical reference for the development of the contemporary Qinba Mountains.

The development rule of man-land relationship and sustainable development for the artifi cial oasis in the east of north slopes of Tianshan Mountain

The paper researches on the pattern of man-land relationship of artificial oasis in the east of north Tian-shan Mountain,the development of Qitai artificial oasis and its relationship with envirorvnet.analyzes the facors influencing the change of Qitai artificiul oasis and its relationship with envirorunent,analyzes the factors influencing the change of Qitai artificial oasis and economic growth through grey analysis,and suggests the approaches of sustainable development of Qitai artificial oasis.Research shows that the pattern of artificial oasis and its environment had gone through three phases：the relatively harmonious stage.the unharmonious stage,and the new fragile balance stage.It also shows that the garden and the shelter-forest are useful to the sustainable development of Qitai oasis according to grey analysis.

Fan‐hinged shear instead of frictional stick–slip as the main and most dangerous mechanism of natural,induced,and volcanic earthquakes in the earth's crust

Frictional stick–slip instability along pre‐existing faults has been accepted as the main mechanism of earthquakes for about 60 years,since it is believed that fracture of intact rocks cannot reflect such features inherent in earthquakes as low shear stresses activating instability,low stress drop,repetitive dynamic instability,and connection with pre‐existing faults.This paper demonstrates that all these features can be induced by a recently discovered shear rupture mechanism(fan‐hinged),which creates dynamic ruptures in intact rocks under stress conditions corresponding to seismogenic depths.The key element of this mechanism is the fan‐shaped structure of the head of extreme ruptures,which is formed as a result of an intense tensile cracking process,with the creation of inter‐crack slabs that act as hinges between the shearing rupture faces.The preference of the fan mechanism over the stick–slip mechanism is clear due to the extraordinary properties of the fan structure,which include the ability to generate new faults in intact dry rocks even at shear stresses that are an order of magnitude lower than the frictional strength;to provide shear resistance close to zero and abnormally large energy release;to cause a low stress drop;to use a new physics of energy supply to the rupture tip,providing supersonic rupture velocity;and to provide a previously unknown interrelation between earthquakes and volcanoes.All these properties make the fan mechanism the most dangerous rupture mechanism at the seismogenic depths of the earth's crust,generating the vast majority of earthquakes.The detailed analysis of the fan mechanism is presented in the companion paper“New physics of supersonic ruptures”published in DUSE.Further study of this subject is a major challenge for deep underground science,earthquake and fracture mechanics,volcanoes,physics,and tribology.

试论梁启超对西方近代地理学在中国传播的贡献

阐述在清末民初西风东渐日益强劲的背景下,维新派的代表人物梁启超在推介西方近代地理学关于人地关系、地理环境决定论等方面的贡献和影响,同时指出梁启超也是最早正确评价徐霞客其人其事的一位学者。这都是中国地理学史上的大事,但为已有的中国地理学史所不载,应对梁启超的以上贡献给予充分肯定和公正评价。

Profile, spectrum and significance of hepatitisB virus genotypes in chronic HBV-infected patients in Yunnan, China

BACKGROUND: There are significant variations in the geographical distribution of hepatitis B virus (HBV) genotypes throughout the world, and some genotypes are associated with different clinical outcomes. Eight genotypes of human HBV (designated A-H) have been reported. The present study was designed to examine the distribution of HBV genotypes among patients at various stages of chronic type B liver disease in Yunnan Province, China, and to explore its significance and the relationship of HBV genotype with gender and age, clinical spectrum of chronic HBV infection, and viral replicative activity. METHODS: Serum samples from 126 patients with chronic HBV infection from Yunnan Province, including 26 chronic asymptomatic HBV carriers (ASC), 61 patients with chronic hepatitis B (CHB) (21 mild, 30 moderate and 10 severe), 20 patients with chronic fulminant hepatic failure (CFHF), 12 patients with HBV-related liver cirrhosis (LC) and 7 patients with HBV-related hepatocellular carcinoma (HCC) were analyzed using reverse dot blot (RDB) methodology, which is based on the reverse hybridization principle for HBV genotyping. The relations of HBV genotype with gender and age, clinical patterns, and serological data of the patients were analyzed. RESULTS: In this series, genotypes A, B, C, and D were found. 38.1% patients (48/126) belonged to B, 54.8% (69/126) to C, 0.8% (1/126) to D, 1.6% (2/126) to a mixture of B and C, and 1.6% (2/126) to a mixture of A and C. 3.2% patients (4/126) had unknown genotypes. No other genotypes (E, F, G, and H) were found. Genotypes B and C were predominant. There was a statistically significant difference in the distributions of genotypes C and B (chi(2)=7.04, P=0.008), and C was the dominant genotype in all patient categories. The rate of genotype B in the mild CHB group was significantly higher than that in the moderate and severe groups (chi(2)=12.16, P=0.0001; chi(2)=11.98, P=0.001, respectively), the ASC group (chi(2)=5.46, P=0.02), the CFHF group (chi(2)=5.53, P=0.019), and the LC/HCC group (chi(2)=12.13, P=0.001). The rate of genotype C in the LC/HCC group and the severe CHB group were significantly higher than that in the mild group (chi(2)=9.95, P=0.002; chi(2)=8.78, P=0.003, respectively). HBV DNA positivity and HBeAg positivity were higher in genotype C than in genotype B (chi(2)=9.81, P=0.002; chi(2)=3.85, P=0.05, respectively). The prevalence of genotype C showed an increasing trend in lowest-, middle- and highest-level groups of HBV replication (25.0%, 70.0%, and 55.6%, respectively); in contrast, the prevalence of genotype B showed an opposite trend in the same order (62.5%, 30.0%, and 37.0%, respectively). The rate of genotype C in the highest-level group of HBV replication was higher than genotype B (chi(2)=7.45, P=0.006). The rate of genotype C in the over-30 age group was higher than that in the below-30 age group (chi(2)=3.7, P=0.05). There was no difference between the sexes (P>0.05). More severe liver damage was found in genotype C than in genotype B (P<0.05). CONCLUSIONS: The predominant HBV genotypes in chronic HBV-infected patients are B and C, and C is the most prevalent genotype in Yunnan Province, China. HBV genotype C is associated with the development of more severe liver disease and a higher level of HBV viral replication, and genotype B has a relatively good progress.

STATUS AND DYNAMIC CHANGE OF REGIONAL MAN- LAND SYSTEM IN VIEW OF MICRO-LEVEL QUANTITATIVE ASPECT -Case Study of Gongyi City of Henan Province

A micro-level analysis on man-land system is important in understanding the content of human geography in rural areas, particularly in the different regions. This paper is based on a survey undertaken in the three villages of Wugou Village, Hutuo Village, and Xiaonan Village of Gongyi City, ltenan Province in April 2003. The survey covers three types of economic and social activities from 214 households. Data collected include 120 attributes for each household. By using theories from the relevant disciplines such as geography, mathcmatics, physics, ecology, and system sciences, this paper develops a framework employing the concept of system entropy in the status function of the man-land system. In this framework, the entropy change is used to show the evolution of the system, and the entropy flow to express the flow among the spatial parts of the system. Following the framework, and using a large set of household data from surveys, the paper makes a quantitative analysis of the village-level man-land system from a micro-perspective. After a theoretical investigation, the corresponding strategies in the paper are then put forward in order to adjust the unbalanced trend of the village man-land system from both perspectives of small-area and individual actors.

明清湖北茶叶及其生产分布

明清湖北茶叶及其生产分布梅莉一明清是中国茶叶生产、制茶技术继往开来的时期。明洪武Ｍ十四年（１３９１），朱元漳命罢龙团凤饼，改为“采芽以进”，开创了散茶的全盛时代。散茶的制作普遍改蒸为炒，炒青绿茶及其制作技术得到显著发展。与此相适应，饮茶方式由过去烹煮...

Another strategy to assess sustainable development

The goal of sustainoble development is to preserve sustainabitity trod simultaneously prevent catastrophe in a man-land .system. However, almost all the existing approaches to assessing sustainable development are to measure the sustainability. namely appraise from the obverse side of the sustainable development. So it seems necessary to attack the same task on the reverse, namely to measure the passibility of eatostrophe. In this paper, with a case study of Tianjin, China. we employ catastrophe theory and models to integrate Tianjin＇s sustainable development indicators, and then deduce the catastrophe risk index （ CRI） to present the level of catastrophic possibility in the city. Applying catastrophe theory, is a new strategy to assess sustainable development and shows great practical significance, especially for those developing regions or countries, who always give more priority to their economy and therefore have more obligation to make sure whether their social economic activities might bring forth any ecological environment catastrophe. Besides, being both qualitative and quantitative, the approach could be employed to explore not only static characteristics bat also dynamic mechanism of man-land system. Although our work is only a maiden attempt and still calls for further effort to improve it, the case study of Tianjin in this paper would assure as the great promising future to apply, catastrophe theory to sustoinable devetopment modeling,

A THEORETICAL DISCUSSION ON TYPES AND MEASUREMENT OF SUSTAINABLE DEVELOPMENT

Classifying the types and measurin g sustainable development are important contents of theoretical studie s on sustainable development.Scient ifically reflecting the characteristics of sustainable development an d favorably classify-ing the types of sustainable develop ment are the basis and objective of me asuring sustainable development.B y using the methods of coordinatively analyzin g man-land relationship and economi c analysis,especially by combining with constant elasticity of substitution(CES)production function,this paper advances average sustainable gross dom estic production(ASGDP),inquires into the mutually coordin ative and interdependent relationship between humane capital and natur al capital in the process of sustainabl e development.It also sets up an index system of measuring sustainable development and a type systemof sustainable deve lopment.then according to this index system,if firstly classifies the s ustainable develop-ment,moderate sustainable develop ment,and strong sustainable develo pment,and it also discuss them theoretical signifi-cance.Secondly,it probes into the minimum cost,structure optimizatio n and sustainable development.At la st,it dis-cuss the type classification of sustainable development on development sequence,and points out theoretically the amount of transitions among 8basic regional sustainable development types is 56.in the process of productive expan sion this transi-tion type embodies the input increase of humane capital is greatly larger than that of natural capital.On the c ontrary,econo-mized humane capital transition is a result of progressively decreasing marginal rate of technical substitu tion of humane capital to natural capital.

KNOWLEDGE DISCOVERY OF REMOTELY SENSED DATA FROM ECOLOGICAL VIEW——A Case Study of Urban Spatial-temporal Relationship in the Pearl River Delta

From the ecological viewpoint this paper discusses the urban spatial-temporal relationship. We take regional towns and cities as a complex man-land system of urban eco-community. This complex man-land system comprises two elements of ' man' and ' land' . Here, ' man' means organization with self-determined consciousness, and ' land' means the physical environment (niche) that ' man' depends on. The complex man-land system has three basic components. They are individual, population and community. Therefore there are six types of spatial relationship for the complex man-land system. They are individual, population,community,man-man, land-land and man-land spatial relationships. Taking the Pearl(Zhujiang) River Delta as a case study, the authors found some evidence of the urban spatial relationship from the remote sensing data. Firstly, the concentration and diffusion of the cities spatial relationship was found in the remote sensing imagery. Most of the cities concentrate in the core area of the Pearl River Delta, but the diffusion situation is also significant. Secondly, the growth behavior and succession behavior of the urban spatial relationship was found in the remote sensing images comparison with different temporal data. Thirdly, the inheritance, break, or meeting emergency behavior was observed from the remote sensing data. Fourthly, the authors found many cases of symbiosis and competition in the remote sensing data of the Pearl River Delta. Fifthly, the autoeciousness, stranglehold and invasion behavior of the urban spatial relationship was discovered from the remote sensing data.

Dynamic Variation and Correlation of Pericarp Tenderness and Component Contents of Super Sweet Corn(sh_(2))in Kernel Development

Data on the mechanism of how pericarp components in fresh sweet corn affect pericarp tenderness are scarce.This study explored variation and correlation of pericarp tenderness and components over time in three inbred lines of sweet corn that were selected for their differences in pericarp tenderness.The three lines presented a curvilinear increase in pericarp tenderness(puncture reading)from 12 to 24 d after pollination(DAP)across two environments,with the means at each time point always in the same order:S33205>T105>PE10.Pericarp tenderness difference at each same time point in two environments over time varied similarly in each of the three inbred lines:increasing first,then dropping after peak,and insignificant at the end.Of the main pericarp components,mean contents were in the order:hemicellulose>cellulose>lignin in both environments at each time point for the three inbred lines.As the pericarp developed,hemicellulose content increased gradually,lignin content varied along a single-peak curve,cellulose content fluctuated around 24%,and pectin and ash contents changed slightly and irregularly.The pericarp of PE10,with the most tender pericarp,accumulated hemicellulose faster than other two lines.Hemicellulose and lignin contents were significantly correlated with pericarp tenderness,and the main components affected pericarp tenderness.

Dreaming Forward: Postidentity and the Generative Thresholds of Tourism

This manuscript from Hollinshead and Vellah calls for researchers in Tourism Studies and related Fields to reflect upon their own role in refreshing the social imaginaries of“after-colonialism”under the nomadisms of our time.Deleuzian in outlook,it positions the“post”of postcolonialism not as an end to colonialism’s imperatives but as a generative-portal through which new-seeds-of-”becoming”are discernable as the postidentities(rather than the“identities”)of populations are interpretable in multidirectional,non-hierarchical,and not easily-predictable ways.In provoking(after Deleuze)thought per rhizomatic processes(rather than via fixed concepts),the manuscript-critiquing these dynamic matters of“postidentity”-then harnesses the insights of(Leela)Ghandi’s on hybrid-nomadic-subjects,and of Venn on alternative-(com)possible-futures.Thereafter,these concerns of and about“after-colonialism”are critically contextualised within Aboriginal“Australia”,via the views of a pool of Indigenous intellectuals there,who synthesise the disruptive dialectics of belonging-cum-aspiration which they maintain that they and fellow Aboriginal people(of many sorts)face today.Throughout this manuscript,the agency and authority of tourism hovers in its sometimes-manifest/sometimes-latent generative power to project empowering postidentities for the world’s“host”or“visited”populations today.

Research progress in man-land relationship evolution and its resource-environment base in China

Man-land relationship research, as the core of geographical research, runs through each development stage of Geography. Based on extensive literature review, this paper systematically generalizes the connotations, research development and contents of man-land relationship in China. （1） It explores the connotations and evolvement rules of man-land rela- tionship in different social development stages in China, and finds that the core role of man-land relationship in geographical research has been strengthened continuously. Changing with times, its connotations have been considerably enriched by sustainable de- velopment and other notions, and so does its theoretical system. （2） It applies the bibliometric method to sketch out the basic research status of man-land relationship in China. Specifically, it quantitatively identifies the funding sources, major research teams and journals for publica- tion. It finds that the funding sources show a diversification trend with national funding being the primary source of research grants. The most competitive research teams are mainly concentrated in the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences （CAS） and normal universities. Journals sponsored by The Geographical Society of China are most influential in publishing man-land relationship re- search. （3） As resources and environment are the fundamental carriers of man-land rela- tionship, this study focuses further on the research on resource-environmental base of man-land relationship, and finds that the resource-environmental base research in China has gone through an evolution process from single factor perspective research to comprehensive multiple perspective research gradually. Research themes have also experienced similar changes from land, water, energy minerals or other single factor research to comprehensive factor research of resources and environment. Empirical study on national and regional de- velopment strategies is the feature of man-land relationship in China. More emphasis should be put on considering and following the changes in features of ＂man＂ and ＂land＂ and research on the impacts of new factors on man-land relationship in a developing and dynamic manner in the future. Particularly, we should pay more attention to research on the impacts of spa- tio-temporal changes in resource-environment absolute location on modes of man-land in- teraction, and to strengthening interdisciplinary research and systematic research on comprehensive techniques so as to advance the development of application of man-land rela-tionship theories and practices.

The classification and assessment of vulnerability of man-land system of oasis city in arid area

Oasis city system is the center of the man-land relationship in arid area and it is the most influential spatial and temporal multiple dynamic system. Oasis city system is not only the largest area where artificial disturbances occur at a regional scale but also the most concentrated area of human activity in arid area. In this study, we developed an applicable and convenient method to assess vulnerability of man-land system of oasis cities with vulnerability indicator system, respectively evaluating the sensitivity, adaptability and vulnerability of the eco- environment system, the economic system and the social system. The results showed that the sensitivity and vulnerability of oasis cities in Xinjiang, China have significant differences while their adaptability does little. In order to find the inherent differences in the vulnerability of oasis cities, triangle methodology has been adopted to divide Xinjiang oasis cities into five types. Some adaptive developing policies specific for individual cities are also proposed based on their vulnerability type and constrain- ing factors.

Rural land engineering and poverty alleviation:Lessons from typical regions in China

Poverty is a key issue restricting rural sustainable development; concurrently, regional land degradation impedes agricultural development and rural revitalization. China faces severe land degradation and deepening rural poverty under the context of rapid urbanization. To address these challenges, sustainable land use is an important tool in our society's economic development. Rural engineering, including rural land consolidation, reclamation, restoration, reallocation, improvement, and development, is the most direct and effective way to achieve rural sustainable poverty alleviation. This study clarifies the framework between land engineering and rural poverty alleviation, and introduces land engineering technologies, newly created land utilization practices, and the contributions to poverty alleviation in representative degraded land regions. Land engineering can increase land quantity,improve land quality, enhance land ecological function, and promote man-land system coupling. Further, it can erase rural poverty by increasing county revenue and households' income, lead to industrial development, and improve living environment. Specifically, degraded sandy land, gully land, hollowed construction land, and barren hilly land are transformed into productive land by improving the land structure. Innovated land engineering technologies and sustainable land utilization modes can provide the basic theories and reference approaches for rural poverty alleviation. Identifying obstacles to effective land and corresponding engineering practices are crucial to regional land exploitation and development, improving quality of life and alleviating rural poverty.