Current Research Situations,Problems and Recommendations of Land Use Structure and Layout Optimization

Land is the foundation for human survival and development,and all human social and economic activities are inseparable from the land as a space carrier.With the continuous development of China's social economy,China is facing new social development needs such as urban-rural integration and rural revitalization.At the same time,China starts to attach great importance to ecology and has proposed the concept that lucid waters and lush mountains are invaluable assets.In this situation,the rational use of land resources,the optimization of land use structure and layout are also facing new challenges and problems,and more comprehensive consideration is required to make relevant optimization.Using the method of literature comparative analysis,from the conceptual connotation,basic theory,method model,and specific practice of land use structure and layout optimization,this paper analyzed and summarized the current research situations and problems,and finally came up with recommendations for the future research.

Visual analysis of the research situation of corona virus disease 2019

Objective:To understand the research status of corona virus disease 2019(COVID-19),analyze research hotspots and dynamic frontiers,and provide ideas for the research of COVID-19.Methods:Bibliometrics method was used to retrieve documents related to COVID-19 research through China National Knowledge Infrastructure,Web of Science,Pubmed databases,and the number of literature data,author,country,institution,source,keywords using CiteSpace,SPSS,Excel perform statistical analysis on other aspects,explain the current status and development trend of new coronavirus pneumonia research,and analyze and identify the research hotspots and dynamic frontiers of COVID-19 through the visual presentation of knowledge graph.Results:With the global spread of the new coronavirus pneumonia epidemic,a large number of studies on COVID-19 have been performed worldwide.In this paper,a total of 7,647 articles were retrieved through a database search,and 5,182 documents that met the criteria were selected for bibliographic analysis,including 2,388 Chinese documents.Articles,2,794 English literature,a total of 94 countries,3,985 institutions,10,339 authors participated in the relevant research of COVID-19,involving 999 kinds of journals,the Chinese scientific research team played a major role in the COVID-19 research,providing an important epidemic situation related research results.Conclusion:The current research focus is primarily on disease recognition,epidemic prevention and control,traditional Chinese medicine,clinical diagnosis and treatment,and epidemiology.

Commentary of research situation and innovation frontier in hydro-structure engineering science

In order to utilize water and hydropower resources in China,multitudes of water projects are established or to be constructed as an integral part of the national economy's infrastructure.Under these circumstances,there are two outstanding problems:1) a mass of existing dams are in danger and 2) in the southwest water-conservancy construction plan,dozens of existing or planned dams are high dams or even super high dams with heights between 200 and 300 m.In accordance with demands of "the National Program for Medium-and Long-Term Scientific and Technological Development" on the innovation frontier in hydro-structure engineering science,various key problems in science and technology such like stress analysis,ultimate bearing capacity,nonlinearity etc.for high dams,super high dams and sick dams have been investigated.This paper makes a commentary on the advances and results of the researches,then analyzes the advantages and disadvantages of current theoretics and methodologies,and finally presents corresponding research directions and the frontier of innovation.

Research situation and progress of non-equilibrium plasma chemistry

Generally, the non-equilibrium plasma is produced at low pressure by a glow discharge (1.33Pa-1.33 kPa) including the radio frequency (13.56 MHz), microwave (2450 MHz), AC or DC high voltage discharges. As a method to directly apply energy to a reaction system, some successful applications have been obtained in the fields such as chemical synthesis and decomposition at plasma, sputtering and filming, deposition at the gas state, polymerization, modification on the material surface, etching, ashing at low temperature and so on. For example,

Research present situation and analysis on classification of rock drillability

Rock drillability reflects the drill bit fragments rock hardly or easily. At present, rock drillability classification indexes have rock single axle compressive strength, point load intensity, fracture stress during chiseling, drill speed, chiseling specific work, acoustic parameter, cutting magnitude and so on. Every index reflects rock drillability but isnt overall. It is feasible that using many indexes of fuzzy mathematics method etc. to evaluate rock drillability.

Research Progress and Present Situation of Tridimensional Reservoir Development

Designing special well patterns, tridimensional reservoir development selects a variety of wells and uses the gravity energy to maximize the hydrocarbon recovery. It's a new development model to implement the oil and gas exploitation economically and efficiently. It is suitable for both huge oiliness altitude reservoirs and large dip-angle sandstone reservoirs, and more for the carbonate reservoirs developed in high-angle fractures, volcanic reservoirs and metamorphic reservoirs.

Research and Application of Hypobaric Storage Technology in Agriculture and Food Industry in China

In recent ten years in China,the application research of hypobaric storage was extended to the non-freeze preservation of cooked food,fresh-cut vegetables,edible fungi and fruits,preliminary processing of growing area and vacuum cold fresh chain to the cold chain breakage for horticultural products,and also to the investigation of principle and theory but the investigation results would have some evident difference. This paper will simply summarize the basic conception,principle,two withdrawing air type hypobaric storage technologies,and introduce many examples as mentioned above extending in China. This paper thinks that the master mechanism of preservation of LP for fresh horticultural products effectively inhibits the activity change of manifold enzymes,which are PAL,POD,PPO,CAT,CAD,SOD et al.,affecting the maturation and caducity of fresh horticultural products during LP storage for a short period,as a result,to reduce both risk of physiology obstacle and disease and to prolong their postharvest life; for the foreseeable future Burg's hypobaric storage technology and hypobaric short period treatment technology will play an important role in the preservation on fresh agricultural products and food preservation in storage and transportation,the preliminary processing of growing area,fresh logistics,establishing the operating platform of perishable food and high business value,fresh e-business,and fresh delivery for scattered families,establishing the operating platform of fresh-cut vegetables including edible fungi and so on in China or in the world.

Advances in Researches of Functional Rice

Functional rice has functions of adjusting human physiological functions of and preventing diseases. At present,there are researches both at home and abroad about the relationship between nutritional quality and physiological active substances of rice and human physiological activities. Through conventional breeding,gene mutation technology,and molecular-assisted selection( MAS) technology,it is feasible to select and breed new rice varieties and plants with certain health care functions.

认知语言学研究新进展:隐喻研究的情景化和话语化——兼评《对空间的再审视:建筑师评议建筑空间的比喻性话语》

通过对《对空间的再审视:建筑师评议建筑空间的比喻性话语》一书的述评,探讨了认知语言学研究的新进展,即隐喻研究的情景化和话语化,并对认知语言学未来发展的研究路向提出了自己的见解:将认知语言学理论的见解同话语分析的程序结合起来以便广泛地考察隐喻在交际中的作用。

Investigations and prospects of Fabry-Perot antennas:a review

Fabry-Perot(FP)antennas have characteristics of planar structures combined with high gain,and they have been widely used in wireless communications.With the progress of ongoing research,FP antennas have achieved various capabilities,but many of them are still under development,such as lowprofile,wideband,circular polarization,multi-band,low-radar cross section(RCS)and reconfigurable features.This paper discusses the theoretical analysis methods and research progress of FP antennas,and explains the realization methods of different features of FP antennas.In order to indicate different technologies for realizing various capabilities,the key technologies and features of some of the latest designs are described.Finally,the research situation and prospects of FP antennas are summarized to guide their research directions in the future.

General Survey of Soil Seed Bank in China

Soil seed bank refers to the sum of upper litter decay and all survival seeds in the soil. It plays a unique role in restoring the surface vegetation and protecting biodiversity. Chinese scholars have carried out extensive researches on the soil seed bank,and have obtained considerable achievements. On the basis of reading extensive literature,this paper summarized the current research results and found that the research contents of soil seed bank in China mainly involve the following aspects:( i) research method of soil seed bank;( ii) classification system of soil seed bank;( iii) spatial pattern of soil seed bank;( iv) relationship between soil seed bank and surface vegetation;( v) dynamic characteristic and seedling replanting of soil seed bank;( vi) application of soil seed bank in vegetation restoration. On the basis of the above summary,it came up with existing problems and future research direction of China's soil seed bank from system construction,field observation,disciplinary combination,interference factors,and community succession.

景观社会:当代旅游研究的情境主义视角

景观社会理论范式可以溯源于马克思的消费理论,如今已成为当代颇具解释力的社会研究范式之一,对旅游研究尤具启发性。本文梳理了景观社会范式的理论渊源,归纳了其本体论、认识论和方法论,说明了它为景观消费、景观空间文化、情境体验以及后现代景观生产等领域提供的理论框架与方法进路,阐释了其核心概念群和基本理念,展示了景观社会理论范式与旅游现象和研究的双向关系。该研究亦梳理了景观社会范式在国内外旅游领域中已有的实践与方法变迁,进而指出该范式日益丰富的未来领域与本土化实践,为旅游体验研究领域的拓展和深化提供新的理论视角,为分析和解决旅游发展中的社会、文化、空间、消费,以及景观建构等问题提供新的理论路径。