bluuebunny/crossref_metadata_2025 huggingface dataset:
Emerging Challenges to Traditional Security: Pakistan’s Future Prospects
Authors: Aslam Tehmina , Javaid Iqra , Aslam Muhammad Asad
Published: September 2022

As of late, Pakistan has seen new rushes of fierce traditional challenges to its security. Regardless of whether in light of ethnic or fanatic ideologies, Pakistan is at crossroads of security between its eastern and western borders. This presents two particular challenges related to difficulties for contemporary,traditional security orders: the ascent of armed conflict with any state and the governance of a progressively complex internal security vacuum. This paper aims to understand emerging challenges to traditional security, mainly focusing on the threat to Indian Ocean Region (IOR) through the lens of technological advancement in armed conflict. By using a qualitative secondary data approach, the author will conduct anin-depth review of the secondary data in the area of traditional security flux and Pakistan’s future prospects.The paper will also analyze Pakistan's deterrence and the biggest traditional security challenge from India with a lens of the development of weapon frameworks as far as disastrous capacities and expansion in range,drones, satellite monitoring and more. Finally, the paper will conclude with the possible ways to curb the emerging challenges to traditional security.
China’s Rise in the Contemporary World
Authors: Malik Alina , Kayani Saima A , Karim Asia
Published: September 2022

The advent of the 21st century has seen a shift from uni polarity to multi polarity, mainly due to China's rise. Chinese ambitions are aligned and expansive, which are driven by nationalism, economic uplift and military modernization. China is evolving as a major powerhouse of the current world order. Trade,economic reforms, up gradation of the military, appealing to the masses through its culture and peaceful settlement of disputes are Chinese means for shaping new world order. America's decreasing sphere of influence in multilateral agreements such as the Paris Agreement and the Iran Nuclear deal is proving windows of opportunities for rising powers like China. China aims to strengthen its position in the international system.
US China Trade War: Implications for the World
Authors: Khan Muhammad Arif , Khan Shahnawaz Muhammad
Published: September 2022

In 2018, a trade war started between USA and China. Both the countries started to apply tariffs against each other. In March 2018, the USA applied tariffs on imports from China. Then in return, China also applied tariffs on a few products. With time, this trade war between both economies raised, and its further intensification made both countries suffer through imposed tariffs. Tariff wars between the United States and China have the potential to undermine global financial stability. As the world's biggest economies, China and USA have been merchandising products and services on a worldwide scale. After these countries retaliate,the tariff war will have an impact on the global distribution chain, international trade, the economy, and equity markets. The study is a qualitative-based critical analysis of the reasons and effects of this trade war between the two economic giants. It also explicitly highlights the environmental as well as economic impacts on the world community.
The impact of housing cooperative bankruptcy on the status of persons entitled under ownership rights to premises. Selected comments on a change in the Supreme Court’s position
Authors: Misztal-Konecka Joanna
Published: September 2022

The article presents an extremely important shift in the judicature by Poland’s Supreme Court as regards the assessment of the consequences of the transformation of the cooperative ownership right to a residential unit into the right of independent ownership of a residential unit in the wake of the housing cooperative’s bankruptcy proceedings. Originally, the Supreme Court held that a mortgage that encumbered the cooperative's real estate at the time of the transformation encumbers ex lege the resulting right of the independent ownership of a residential unit. Not until 2019 did the Supreme Court abandon this controversial position, and the ultimate change in its judicature is supported with a wide array of critical underlying motives. The author approves of the recently adopted judicial trajectory, yet with a proviso that the resolution of problems it pertains to be not left to the judicature only, as it requires the definitive intervention of the legislator.
PENGARUH KETERLIBATAN MEDIA SOSIAL, PLATFORM MEDIA SOSIAL TERHADAP KEGIATAN KONSUMSI RUMAH TANGGA DI INDONESIA
Authors: Herispon Herispon
Published: September 2022

This study examines the effect of the involvement of social media and social media platforms on household consumption activities, investigates the type and number of activities involving social media in household consumption. Using the household unit as the population and represented by one person or the head of the family as the sample, as many as 717 respondents. sampling method; convenience sampling. This study found, that; the involvement of social media and social media platforms has a statistically significant effect of 29 percent at a moderate level of influence on household consumption activities. This study can explore as many as 27 types of consumption activities in the household involving social media. Conclusion that social media engagement and platforms cannot be separated from current household consumption activities, and it is assumed that more consumption activities will involve social media.

Studi ini menguji pengaruh keterlibatan media sosial dan platform media sosial terhadap kegiatan konsumsi rumah tangga, menginvestigasi jenis dan banyaknya kegiatan yang melibatkan media sosial dalam konsumsi rumah tangga. Menggunakan unit rumah tangga sebagai populasi dan diwakili oleh satu orang atau kepala keluarga sebagai sampel, yaitu sebanyak 717 responden. metode penarikan sampel; convienence sampling. Studi ini menemukan, bahwa; keterlibatan media sosial dan platform media sosial berpengaruh signifikan secara statistik sebesar 29 persen pada level cukup berpengaruh terhadap kegiatan konsumsi rumah tangga. Studi ini dapat mengeksplor sebanyak 27 jenis kegiatan konsumsi dalam rumah tangga melibatkan media sosial. Kesimpulan bahwa keterlibatan dan platform media sosial tidak dapat dipisahkan dari kegiatan konsumsi rumah tangga saat ini, dan diasumsikan akan lebih banyak lagi kegiatan konsumsi yang akan melibatkan media sosial
Skepticism of antitheodicy and evidential argument from evil
Authors: Karpov Kirill V.
Published: September 2022

A distinctive feature of the contemporary debate on the problem of evil is a two-sided critique of theism. On the one hand, there are arguments against the existence of God (or for the low probability of His existence) based on evil. On the other hand, theistic responses to atheistic arguments—theodicies and defences— are criticised in the way of antitheodicy. This criticism relies on the fact that theodicies and defences are justifying evil and suffering or, at least, interpreting them as meaningful. It is obvious that both sides of atheistic criticism rest on the supposedly intuitively knowledgeable fact that there are evil states of affairs and suffering in the world. Appeal to this fact is in the basis of important assumptions, including epistemological ones, of the arguments from evil. These assumptions could be divided into two parts. Firstly, it is the assumption of the immediate givenness of the facts of evil in cognition. Secondly, it is the assumption that the facts of evil serve as evidence against main tenets of theism (e.g. the existence of God, the origin of evil, the possibility of justification of evil in the world). In the paper I analyse these premises within the project of transcendental antitheodicy offered by Sari Kivistö and Sami Pihlström in “Kantian Antitheodicy. Philosophical and Literary Varieties”. I demonstrate that the transcendental antitheodicy simultaneously plays two roles in the discussion. On the one hand its scepticism (the impossibility to know the suffering of another) allows to get rid of “an evidentialist game of argumentation”, on the other hand, the basic proposition of the transcendental antitheodicy might be seen by theodicists as rebutting defeater and hence it still in the “evidentialist game”.
Commentary on the Book of Helen Pluckrose and James Lindsay “Cynical Theories” (Applied Postmodernism, the Concept of Social Justice, Queer Theory)
Authors: Rozin Vadim M.
Published: September 2022

The article discusses a book by H. Placrouse and J. Lindsey. They analyze the theories of applied postmodernism in some detail, showing that these practices emerged from the applied turn of postmodernism. Another source is the social justice movement and concepts. The main ideas of applied postmodernism are formulated: the absence of metanarratives and belief in objective reality, the constructiveness of social reality and concepts, the power of language and narratives, the deconstruction of social reality, which is understood as repressive, the restructuring of social life. The reasons explaining the popularity of applied postmodern theories are analyzed: they promise a solution to the problem of social justice for the masses; Universities act as a source of training of unique personnel for the implementation of these theories; firms and the establishment prefer not to oppose the fighters for social justice, hoping to eventually direct their activity in the right direction. Queer Theory is considered in more detail, the subject of which are the phenomena of sex, gender, sexuality, identification in these realities. The author draws parallels between the approach of Queer Theory and esoteric teachings: both here and there, belief in true reality (but differently understood) and the supervalue of a free person. On the example of historical concepts of love, where the social plan prevailed over the biological one, the question of the relationship between these two plans is examined, and in this regard, the negative consequences of the implementation of Queer Theory are outlined. The author shows that social concepts and models transform the biological plan, but not in such a way as to completely cancel it or completely subjugate it. These concepts and models are being corrected in order to ensure, among other things, biological functions and processes, and quite fully, even to raise them to new heights. At the end of the article, it is doubted that following liberal principles and the problems that arise in the course of implementing cynical theories will quickly lead to disillusionment with applied postmodernism.
NTNG1 Modulates Progressions of Prostate Cancer Cells through JAK/STAT Signalling Pathway
Authors: Xie Yabin
Published: September 2022

Netrin-G1 (NTNG1) is a glycosyl-phosphatidylinositol-affixed synaptic adhesion molecule that participates in carcinoma developments. However, its underlying mechanism in regulating prostate cancer (PCa) is uncertain. NTNG1 mRNA and protein expressions in prostate cancer tissue samples and cells were demonstrated to be promoted using RT-qPCR and western blot. Thereafter, using CCK-8, NTNG1 overexpression accelerated PCa cell viability while suppressed NTNG1 restrained cell viability. Additionally, transwell results indicated that migratory and invasive abilities of PCa cells were also facilitated by overexpressed NTNG1 but inhibited with NTNG1 suppression. Furthermore, using RT-qPCR, Janus kinase 1 (JAK1) has been detected to be upregulated by NTNG1 upregulation but suppressed with NTNG1 downregulation. Moreover, JAK1, JAK2, signal transducer and activator of transcription 3 (STAT3), Ki67 and E-cadherin protein expressions were also suppressed by the knockdown of NTNG1 but elevated with NTNG1 overexpression. In PCa cells, NTNG1 acted as an oncogene through activating JAK/STAT3 signalling pathway.
Sumberdaya Ikan Asli dan Invasif di Sungai Mengkiang, Kabupaten Sanggau, Kalimantan Barat
Authors: Peronita Via , Hadinata Fitra Wira , Trismiyarto Riwut Eko , . Jafar , Widodo Aman Bayu , . Ismanto
Published: September 2022

Mengkiang River is a river located in Sanggau Regency. Information from local communities and fishermen Information related to the waters of the Mengkiang River, there are several types of fish that are protected, invasive and endemic.This study was conducted to determine the condition of native and invasive fish resources in the waters of the Mengkiang River. The information from this study is expected to be used to formulate control measures as input for the formulation of regulations and policies by the government. Sampling was carried out at 3 observation stations, namely the upstream, middle, and downstream parts of the river. The aim is to show the value of sommunity structures such as index of fish diversities, the similarities, dominances, native and aliens species. The number of fish species that have been identified as many as 8 species, there are 7 native fish, namely: Bilis (Anchoviclla commersoni), Lais (Cyptopterus micronema), Seluang (Rasbora Sp.), Tengadak (Barbonymus schwanenfeldi), Hampala (Hampala macroleptitoda), Tilan (Barbonymus schwanenfeldi), Baung (Mystus) and 1 type of invasive fish, namely Toman fish (Chana Pleurophthalma) Diversity Index Value (H') 1.85861622. The value of the Diversity Index in the waters of the Mengkiang River is included in the medium group, namely moderate distribution and moderate community stability. Stable community that is high similarities Index Value. The Dominance Index value of the Mengkiang River is included in the low criteria. The condition of the waters of the Mengkiang River is still in good and well-maintained condition.
A New Energy Power Grid Expansion Planning Technology Considering Optimal Economy
Authors: Song Xinfu , Xin Chaoshan , Yu Jin , Yu Zhiyong , Shen Danhua , Ma Junliang
Published: September 2022

This paper examines the path of new energy development in China against the backdrop of carbon maximum and carbon neutralization, and studies the risk of large scale new energy power transmission. In order to solve the complex uncertainty challenges of renewables power and power grid expansion planning, this paper studies and proposes an optimal economic planning model, which includes the thermal power generation start-up and shutdown expenses during the operation, the hydro power generation expenses of surplus water of reservoir, and the curtail penalty cost of new energy output power, the investment of new planning lines. The model has also considered the constraints of balance for power generation and load consumption, the power change rate, and operation, which are calculated based on the time-series operation simulation of new energy power system. Based on the functions, the process of power grid planning technology has been proposed. The planning model proposed in this paper can consider the new energy power characteristics of generation, realize the optimal planning of different power grid schemes. According to the case study findings, the new transmission line can relieve the pressure of local new energy transmission, while also improving power flow distribution as well as the rate of new energy utilization.
Study on Flexible Fuel Management Strategy of Haiyang Nuclear Power Plant
Authors: Zhang Weibin , Zhang Qiao
Published: September 2022

Flexible fuel management in a nuclear power plant relates to the operational efficiency of the whole plant, which not only satisfies flexible fuel demands, but also has a positive effect on environmental pollution control. The proposed management strategy aims at improving energy utilization rate of nuclear fuel in nuclear power plants, meeting the needs of peak electricity consumption in summer and nuclear energy heating in winter, enhancing the economic efficiency of nuclear power plants, and reducing carbon emissions, thus contributing to energy carbon neutrality. In this paper, the Core and System Integrated Engine for design and analysis (COSINE) nuclear design software package was adopted to study the fuel management strategy for alternate refueling in 68 groups and 60 groups of assemblies, based on the current 64 groups of refuel assemblies at Haiyang Nuclear Power Plant (NPP). The results show that the Haiyang NPP has the capability to refuel flexibly between 68 and 60 groups of assemblies, and the reactor core design meets the relevant design guidelines and requirements.
Simulation Study on Output Characteristics of Photovoltaic Power Generation Under System Short-Circuit Fault
Authors: Zhang Li , Wang Yudan , Zhao Guo , Zhu Heping
Published: September 2022

Various faults will occur in the power grid during operation, among which the system short-circuit fault is the most common. The introduction of the photovoltaic system has changed the structure of the power grid. The power grid is no longer the original single-source radial structure, but becomes a dual-end or multi-end power grid, thus changing the size, direction, and duration of fault current. It is helpful to study the current output characteristics of photovoltaic systems in a short circuit for the study of the power grid. Therefore, this paper builds a grid-connected photovoltaic generator model on the DigSILENT simulation tool to study the output characteristics in a short circuit. The models are simulated under different conditions of three-phase short circuit, two-phase short circuit, and single-phase short circuit. Through analysis, it is concluded that the current characteristics of distributed generation with a power electronic interface are related to the design of the interface and the control method of an interface when a short circuit occurs.
Research on Capacity Optimization Configuration of Independent Microgrid Including Wind Power/Photovoltaic/Photothermal
Authors: Wang Yudan , Zhang Li , Zhao Guo , Wan Chenxi
Published: September 2022

Independent microgrids have important implications for solving the problem of electricity consumption and electricity consumption in distant islands or hills. This paper takes island micro-grid as the research object, and constructs an independent microgrid with distributed generation, for instance photovoltaic/solar heat/wind/diesel/storage. The goal is to decrease overall investment fee and the probability of insufficient electric supply, a dual-objective capacity optimization configuration model of the microgrid is established. NSGA-II algorithm is to deal with the established model, The best solution of each distributed power type and capacity in isolated islanded microgrid is obtained. The simulation results show that the optimal configuration scheme can ensure that the established microgrid has good economic benefits while ensuring the reliability of power supply.
Research on Collaborative Real-Time Simulation Technology of Multi-Energy Complementary Integrated Energy System
Authors: Wang Yuejiao , Li Mengyang , Sun Shumin , Chen Yonghua , Li Yong , Cheng Yan
Published: September 2022

In order to realize the real-time simulation of regional integrated energy system, a multi-energy flow collaborative real-time simulation technology based on message bus is proposed, and the real-time simulation platform established on this basis realizes the real-time simulation of electrical and thermal systems. By using the co-simulator composed of message-oriented middleware and adapter to coordinate multiple simulators to complete the real-time simulation of the system in the loop, the message bus uses the open source ZeroMQ; it provides a unified message subscription and message publishing mechanism for all real-time simulators. Adapters are used to connect a variety of heterogeneous emulators, such as RT-LAB, TRNSYS, etc., to messaging middleware. Adopting message-oriented middleware and adapter scheme, it has the characteristics of open and extensible. The simulation system developed in this paper can be used in the real time simulation of distribution integrated energy system to realize the interaction between energy flow and information flow.
Experimental Study on CPC Regenerative Solar Air Collector’s Thermal Properties
Authors: Li Guozhu , Wang Shuai , Feng Guohui
Published: September 2022

In this paper, the compound parabolic concentrator (CPC), phase change regenerative heat core and vacuum tube type solar air collector are combined to investigate a CPC regenerative heat solar air collector that combines the functions of regenerative heat and heat concentration. The whole-to-part approach is used to illustrate the construction of this new collector. At the same time, the thermal performance of the new collector is compared with other conventional collectors in terms of collector temperature and operating time through the construction of an experimental system test rig. From the results it is concluded that the CPC regenerative heat solar air collector not only increases the collector temperature but also extends the operating time compared to conventional solar thermal collectors. It achieves a maximum output temperature of 110.8°C. It can operate for approximately 3h longer during the day. The results of this study provide a meaningful reference for the further development of a multi-technology combined solar thermal collector.
Leakage Cause Analysis of Water-Wall Pipe in Subcritical Boiler
Authors: Fang Lulu , Dai Zhen , Zhao Jifeng , Tao Kangning , Zhang Yiwen , Ouyang Quan , Zeng Yong , Chu Xi
Published: September 2022

In view of the local cracking and leakage of water-wall pipe of Subcritical Boiler in a thermal power plant, the cracking mechanism of water wall pipe was studied by means of macroscopic analysis, chemical composition analysis, metallographic structure, Brinell hardness test, tensile test at room temperature and scanning electron microscopy. The results show that there is no misuse of materials or unqualified chemical composition in the cracked and leaked water-wall pipe. There are a large number of corrosion deposits and corrosion pits on the inner wall of the pipe, showing obvious corrosion characteristics under the scale. Compared with the local position of the inner wall of the pipe section, tumor corrosion products are also found, indicating the overall corrosion of the pipe section. Corrosion under the scale causes the thickness of pipeline to be reduced continuously. The pearlite spheroidization in the microstructure near the leakage crack is grade 4, and a large number of holes and intergranular cracks can be seen. At the same time, there is a large number of oxide scale and obvious decarburization layer at the edge of the crack, indicating that there is hydrogen corrosion near the crack, making the hardness value near the crack lower than the standard value. Therefore, it can be inferred that the main causes of cracking of water wall tubes are under scale corrosion and hydrogen corrosion.
Influence of Greenwashing Strategy on Pricing: A Game-Theoretical Model for Quality Heterogeneous Enterprises
Authors: Zhang Jie , Yang Jianchun
Published: September 2022

Greenwashing behaviors refer to the performance that enterprises claim environmental protection, but their words and actions are inconsistent. The greenwashing strategy has both short-term benefits and negative effects for corporations. In this paper, a model of competition between two companies with different product quality is constructed. This paper explores how the greenwashing strategy of brown enterprises with inferior quality affects the pricing and profits of traditional enterprises without greenwashing motivation. The results show that: (1) the price of greenwashing enterprises is unimodal. Greenwashing companies will improve product quality while reducing prices to ensure a growing market demand. (2) Traditional enterprises fail to regain the market by relying on price competition, and it is more important to reduce the success rate of greenwashing. (3) Only by reducing the success rate of greenwashing, will greenwashing companies lose their greenwashing benefits, and traditional enterprises can regain market shares.
Research on Fragmentation Problems of Big Data Analytics in Environmental Management
Authors: Wang Haijing , Wang Yaping
Published: September 2022

Fragmentation is a common but critical problem of big data analytics. Although big data analytics have the 5-v benefit, including volume, variety, veracity, velocity and value, fragmentation may make such benefit illusory. The benefit of big data analytics is based on the complete coverage of data collection and the sharing of data among multiple levels and multiple branches of the organization. A field investigation is conducted to test the big data analytic systems of an environmental protection agency of a province in China at the level of province, prefecture, and county. This field investigation reveals that the data collection coverage fails to cover some essential aspects, particularly when such data are generated by other governmental branches. The field investigation also reveals that the data are not shared among different levels or different branches of the government, which leads to the problems of fragmentation. Further investigation reveals that this fragmentation mainly lies in the insufficiency of prediction in the design of database framework and the fragmental purchase of big data analytic services. This paper recommends predictive designing in the initial design of the framework of big data analytic systems so that it may better accommodate changes in the future.
Research Progress of Radiation Refrigeration Materials
Authors: Guan Haifeng , Su Lin , Dong Kaijun , Zhang Bobo
Published: September 2022

Radiation cooling radiates heat to outer space through the atmospheric window. There is no energy consumption for the effect of refrigeration. Materials are the key to realizing radiation refrigeration. This paper mainly focuses on radiation refrigeration materials, summarizing some types of requisite materials, including the progress of making radiation refrigeration materials and the kinds of products. Furthermore, it also analyses some radiation effects that various radiation refrigeration products will bring, such as radiation refrigeration film and radiation refrigeration coating. Finally, it looks forward to the future development trend of radiation refrigeration materials.
Effect of Microstructure on Mechanical Properties of Cornstalk
Authors: Xu Yan , Jiang Yinlong , Cai Yungao , Yang Huxia
Published: September 2022

The research on the mechanical properties of cornstalk, a natural biomass, is of great significance in the fields of deep-processing and reuse, preparation of biomimetic materials and so on. In this study, an electronic universal material testing machine was used in the macroscopic mechanical property test of cornstalk radial compression, axial compression, cutting, and three-point bending. The microstructure of cornstalk rind and cornstalk pith was characterized by scanning electron microscopy (SEM), and the effect of microstructure on mechanical properties of cornstalk was revealed. Mechanical properties of cornstalk mainly depend on the pith in radial compression, and mainly depend on the rind in other loading modes, and the relationship between the mechanical properties and the microstructure of corn stalk is revealed from the microscopic scale.
Forecast and Solution of Urban Freight Distribution Demand in Xiamen
Authors: Liu Xiaolei , Zhang Haiying , Zhou Yalin , Chen Shuxue , Luo Kai , Shi Lei
Published: September 2022

In order to face the challenge of changing market demand, it is necessary to reasonably predict the demand for urban freight distribution in Xiamen and solve the market development potential problem. Firstly, by using Pearson correlation test and multiple regression analysis method, this paper fully considers the influencing factors of demand prediction, and forecasts Xiamen’s urban distribution demand of postal services, and the urban distribution demand of grain and oil, fresh food, FMCG, etc. The forecast results show that by 2025, the total postal services will reach 28.2 billion yuan, and the urban distribution demand for grain and oil, fresh food, FMCG and other products will reach 38.5 billion yuan. Then, based on forecasting the future demand of Xiamen’s urban freight distribution, this paper analyzes the problems in the development of Xiamen’s urban freight distribution, and proposes solutions accordingly, aiming to promote the efficient and high-quality development of Xiamen’s urban distribution.
Sustainable Development of Forest Management – Transition Point Analysis Based on Forest Value Assessment
Authors: Zheng Mingsong , Liu Yaxuan , Zhou Ruining
Published: September 2022

Forest ecosystem management research is one of the hot spots and difficulties in forest sustainability development. Because of this, this paper constructs a framework of “integrated forest value assessment-transition point analysis-management strategy decision” from the perspective of integrated forest value assessment and its management strategy decision to maintain the integrity, continuity, and stability of forest ecosystem function. The model is universally applicable, and we obtain the transition periods of most countries in the world based on the model, and quantitatively analyze the forest status of George Jefferson Forest in the United States to obtain the optimal management plan, which verifies the accuracy and reliability of the model.
Scientometric Analysis of Carbon Emission Peaking in China
Authors: Wei Qiang , Lv Dong , Zhu Dongmei , Zhang Jibiao , Chen Si
Published: September 2022

The Chinese government clearly proposed to the international community at the United Nations General Assembly to strive to achieve the double carbon goal. Since then, there has been an explosion of research in the field of carbon peaking, and this paper uses the scientometric software CiteSpace to systematically review the research on carbon peaking in China. The results of this study show that carbon neutrality, carbon emissions, and carbon reduction are popular themes and important mediators in the field of carbon peaking research. The research themes focus on how to reduce carbon emissions and promote low-carbon transition to green development as well as energy structure transformation. The clustering results can be divided into carbon emission reduction, industry energy transformation, sustainable development, and policy regulation.
Comparison Between Remotely-Sensed and Numerically-Simulated High-Resolution Surface Temperatures at an Urban Commercial Site
Authors: Chen Kan
Published: September 2022

This study compares high-resolution urban surface temperatures (Ts) obtained through airborne-remote sensing and from a heat balance simulation model to clarify the characteristics of detailed Ts distributions within an urban district and confirmed the capabilities and limitations of the simulation model for urban Ts assessment. The remote sensing observations were conducted in the daytime of summer and winter. For the heat balance simulation, detailed three-dimensional (3D) geometry and component material data were collected by using a previously developed modeling method, materials database, and field surveys. 3D Ts distributions were simulated for the summer and winter days. Both remote sensing and numerical simulation showed the effects of surface geometry and solar reflectance, and also the time-integrating effects of the heat capacity of materials. The point-to-point comparison of results between the numerically simulated Ts and remotely sensed Tr revealed that the Ts was close to the Tr at many points for both seasons. The Tr values were slightly smaller than those of Ts for these points owing to the effects of surface emissivity. It is confirmed that the heat balance simulation model can effectively simulate Ts distribution through the comparison with the airborne remote sensing data. The factors causing the difference between Ts and Tr were assessed as mixels in the remote sensing image, reproductivity of materials in the model, actual microclimate and anthropogenic heat emission, and the limitation of the heat balance simulation that used a one-dimensional (1D) heat conduction equation.
Mechanical Properties of Reinforced Concrete Under Ultra-Low Temperature Coupled with Load
Authors: Zhang Baosen , Li Yang , Yan Ziyu , Ren Zhaoyang
Published: September 2022

In order to explore the mechanical properties of reinforced concrete members under the action of ultra-low temperature and load coupling, the research group carried out the flexural and axial tension test of reinforced concrete beam members under ultra-low temperature. The test results show that the tensile stiffness increases nonlinearly when the temperature decreases from 0°C to –100°C. When the temperature is below –100°C, the tensile stiffness of concrete beam almost remains unchanged. When the temperature drops from 0°C to –165°C, the constraint strain between the reinforcement and concrete in the concrete beam caused by temperature cannot be ignored and should be considered in the design.
Evolution of Mechanical Property and Microstructure of Fibre-Reinforced Ultra High Strength Mortar with Desert Sand
Authors: Li Tianyu , Shi Fangying , Liu Xiaoyan , Lian Xunhuan , Zhang Jingying , Zhu Zheng , Hu Yuhan , Wang Dezhi , Bao Tengfei
Published: September 2022

Previous research showed that the concrete’s strength is obviously decreased when river sand was substituted by desert sand in abundance. In this paper, a new type of fibre-reinforced ultra high-strength desert sand mortar is studied. In the mix design of mortar, low W/B was used to save water. Also, fly ash and silica fume were adopted to partly replace cement, and desert sand was used to completely take the place of river sand. At the same time, steel fibre was used to improve the toughness. The pore structure changes of different desert sand ultra high strength mortar were studied by MIP. SEM and XRD were adopted to study the microstructure and hydration product changes. The results are as follows: the mortar’s mechanical properties are improved when the desert sand content rise. When desert sand was adopted to substitute river sand completely, the mortar’s compressive strength was increased by 36.91%, which reached 149.08 MPa. With the desert sand’s addition, the mortar’s porosity decreases and its pore structure is optimized. Desert sand played an active part in promoting the hydration of mortar, increasing hydration products, densifying the mortar structure and improving the mortar’s mechanical properties..The research in this paper solves the problem that the high-content desert sand mortar’s mechanical properties cannot meet the demand, and provides the actual application of desert sand in mortar a theoretical basis.
Improved Evaluation Method of Coal Spontaneous Combustion/Oxidation Characteristics
Authors: Zhang Lei , Li Shuaidan , Liu Aohao , Wang Wei , Wang Jiarui , Bao Jun , Li Xiaojiang
Published: September 2022

Coal spontaneous combustion often occurs in storage processes, especially for low-rank coal with high volatile materials, which may lead coal yard caught fire and coal thermal energy losses. Therefore, it is important to accurately predict the spontaneous combustion tendency under coal storage status in real time. In order to determine the ignition point, the existing methods are all using pulverized coal samples, adding special oxidant artificially and then heating to accelerate the oxidation process. The particle size and the test conditions of those methods were quite different from the real coal storage condition. This research developed a new test method to evaluate the spontaneous combustion tendency. The method used granular coal samples, which the particle size is similar to its storage process, to test its temperature increasing under the humidity, pressure and air flow which are similar to its storage conditions. The spontaneous combustion tendency was judged by the temperature rise rate V70 of the sample at 69°C–71°C in adiabatic heating condition. 10 samples of different rank of Chinese coals were used to study. The results show that lignite had the largest low-temperature oxidation heating rate, and anthracite has the minimum. The lower coal moisture, the greater low-temperature oxidation heating rate. When the environment temperature is 70°C, with the increase of air flow rate, the rate of temperature rise increases firstly and then decreases. As environment temperatures rise, the temperature rise rate increases firstly and then decrease for the three types of coal samples, lignite has the maximum temperature rise rate, while anthracite has minimal temperature rising rate. Six kinds of coal samples were selected in order to verify the method precision. It was found that the temperature rise rate and repeatability limit of coal samples have linear correlation, and the basis for judgment and repeatability limit of the method are also provided. The method has high sensitivity and resolution of different coal ranks. According to the research, coal could be divided into three categories: strong spontaneous combustion tendency, medium spontaneous combustion tendency and weak spontaneous combustion tendency according to their temperature rise rate V70. The method could give great practical significant guidance for the scientific storage, blending, safety and efficient utilization of coal.
Numerical Analysis of Axial Compression Performance of Damaged RC Columns Strengthened with GFRP Tube and Steel Fiber Mortar
Authors: Li Zhe , Tian Yu , Wang Zhili
Published: September 2022

In this paper, a new combined form of Glass Fiber Reinforced Plastic (GFRP) column and steel fiber mortar reinforced damaged Reinforced Concrete (RC) column is proposed. With the help of ABAQUS finite element software, the finite element model of GFRP tube and steel fiber mortar reinforced damaged RC column is established. Based on the experiment of GFRP tube and steel fiber mortar strengthening damaged RC column, the parameters such as fiber winding angle of GFRP tube, steel fiber mortar strength and section loading mode are studied by numerical simulation. The results show that the axial compression bearing capacity of the composite structure increases with the increase of the angle between the fiber winding angle of GFRP tube and the 45° winding direction. With the change of steel fiber mortar strength, initial damage of RC column and different loading methods, the bearing capacity results have little change. On the basis of numerical simulation research, the calculation equation of the bearing capacity of damaged RC columns strengthened with GFRP tube and steel fiber mortar is modified by superposition method, and the comparison shows that the agreement is good.
Surrounding Rock Control Technology for Gob-Side Entry Retaining Under Goaf in Deep and Close Distance Coal Seams
Authors: Luo Ciyou , Wang Zijuan , Yan Zihai
Published: September 2022

To solve the technical problems in controlling the surrounding rock of gob-side entry retaining of deep and close distance coal seams under goaf, the surrounding rock deformation and failure characteristics of gob-side entry retaining of deep close distance coal seams under goaf were analyzed in this paper. Basic support inside roadway of the high-strength prestressed wire meshes, beam and cable anchor, reinforcement support inside roadway of the single hydraulic support with the hinged roof beam and roadside support of high-water material filling structure were proposed. The engineering practice shows adopting the surrounding rock control technology, the surface displacement of the filling body and the surrounding rock and the amount of the roof separation are all in the controllable range, the stability of the roadway is good.
Novel Tool of In-Bit Measurement for New Clean Geo-Energy Exploitation
Authors: Chen Xiwu , Huang Zhe
Published: September 2022

With the global economy and industry development, environment-friendly and sustainable development have become the mainstream of energy exploration and utilization. However, due to the complex downhole environment, the rate of penetration increment is becoming an urgent need for the new clean geo-energy exploitation. As the direct actuator of rock breaking, the dynamic response of drilling bit is the embodiment of the relationship among drilling parameters, formation characteristics, and drilling string structures. The acquisition and mining of drilling bit’s dynamic response is the key to coordinate the game relation of drilling efficiency, economic benefit and risk control, and to lay the foundation of optimized drilling and ROP increment. In this paper, based on a series of researches on sensor array designing, hydraulic structure optimization, and data reckoning method, a new type of in-bit measurement tool was proposed for new clean geo-energy exploitation. The functionality and reliability of the novel tool were also proved by a field application in a shale gas development project.
Study on Preparation and Reaction Mechanism of B4C/β-Sialon/SiC/Al2O3 Composite Powder
Authors: Yang Hao , Deng Chengji , Yu Chao , Ding Jun , Zhu Hongxi , Li Xiangcheng
Published: September 2022

B4C, Si, Al, and γ-Al2O3 were used as raw materials, formed β-Sialon and SiC in situ by solid-state reaction for preparation of B4C composite powder. β-Sialon and SiC grains are uniformly and dispersedly distributed in the composite powder. The effects of the molar ratio of raw materials, nitridation temperature and soaking time for the phase composition, and microstructure of the composite powder were studied. When the molar ratio of B4C and Si is 2: 3, the composite powder with columnar β-Sialon grains growing alternately can be prepared after nitridation at 1500°C for 4 h. The liquid phase formed by the melting of Si at high temperature promoted the dissolution of B4C and the formation of SiC. When the nitridation temperature was increased or the soaking time was prolonged, the gas phase volatilization of Si and Al was intensified, SiC and AlN whiskers tend to be formed in the composite powder.
Effect of Pulsed Current on Joining of 7075 T6 Aluminium Alloy by TIG Welding Process
Authors: Belgacem L. , Benharat S. , Sakmeche M.
Published: September 2022

7075 T6 aluminum alloys are applied in aircraft construction. The success of their weldability is a technological challenge bringing advantages in the lightening of structures. This work was carried out in the aim to analyze the mechanical behavior and microstructural evolution of aluminum alloys 7075 T6 sheets welded by TIG process, by applying a pulsed current. A notable microstructural change occurred in our materials by the thermal effect, resulting in degradation of mechanical properties. The break of samples is privileged in the connecting region, which is characterized by a columnar structure, contributing to reduce the ability of the material to deforme plastically.
Fatigue Life Calculation of Mechanical Seal Welded Metal Bellows
Authors: Zhang Lijun , Qi Guo , Kang Jingjie , Tang Shengming , Sun Yuandong , Wang Ruolan
Published: September 2022

For welded metal bellows, bellows are used in mechanical seals to replace springs and other auxiliary sealing coils in seals. When the traditional rotating device rotates at a high speed, the moving ring in the mechanical sealing process will cause the axial displacement, and the bellows can compensate or reduce by relying on its own performance. For other mechanical devices, the failure of mechanical seals will directly affect their performance and life, and the failure of welded metal blowers used in mechanical seals is usually considered as fatigue damage. Therefore, studying the welding process of the bellows is extremely important to its service life. This article mainly studies the fatigue life of mechanical seal welded metal bellows. First, the characteristics of mechanical seal welded metal bellows are described by the literature research method, and then the fatigue life calculation method is summarized. Finally, the use of the experimental research method studied the fatigue life of u-shaped metal bellows and v-shaped metal bellows at temperature differences of 3°C, 4°C, 5°C, and 6°C. The experimental results show that as the temperature difference increases, the minimum fatigue life of the two types of metal bellows decreases with decline. At the same time, it can also be found that the minimum fatigue life of the v-shaped metal bellows has always far exceeded U-shaped metal bellows.
Dynamic Continuous Online Compensation Method for Processing Robot Path Based on External Measurement
Authors: Zhang Hui , Pan Xin , Li Haiwei , Du Jie , Meng Qingxun , Zhang Gang
Published: September 2022

The absolute positioning accuracy of industrial robots is not in the high level to meet machining precision requirements. To improve the practical application requirements of industrial robots in the field of aerospace manufacturing, an online error compensation method based on the external Guided Motion (GEM) function of the milling robot is proposed in this paper. Using external measuring equipment, an external closed-loop control system of the robot is established, and the error compensation scheme is designed. The precision compensation of the robot’s end position is mainly studied. For the linear and circular motion of the robot, a continuous trajectory piecework compensation method is studied by using a PID control algorithm, which can measure the end position error online. The position errors of the robot are compensated simultaneously in the X, Y, and Z directions. Experiments show that the online error compensation method can improve the absolute accuracy of the robot end.
An Approach to Vibration Signal Analysis Using Quantum Probability
Authors: Wu Dinghai , Zhuo Xueyan , Chen Yanlong , Ren Guoquan , Deng Wei
Published: September 2022

When mechanical equipment breaks down under actual working conditions, time domain waveform is blurred by noise, which leads difficulty to acquire useful information. Aiming at this problem, an approach to vibration signal analysis using quantum probability is proposed to process time domain waveform of mechanical vibration signal. By use of superior information processing properties of quantum theory, different states hidden in sampled points of vibration are expressed. The basic states of quantum system are employed to depict waveform change resulted by fault. Then quantum probability is used to fuse fault information and finally the goal of waveform adjustment is achieved. The processing results of measured signal imply that the proposed approach can extract fault information from time domain waveform effectively.
Optimal Boundary Shape of the Center-Reduced Cruciform Specimen for the In-Plane Biaxial Test
Authors: Chen Junxian , Zhang Jianhai
Published: September 2022

Cruciform specimens are one of the most common used to measure the plane mechanical properties of materials. Two significant difficulties in designing cross specimens are reducing stress concentration at the intersection of cross arms and improving stress/strain uniformity in the gauge area. The shape of the border at the intersection of the cruciform specimen is tightly related to the above two. Due to the lack of guidelines for the design of cruciform specimens, optimizing the cruciform specimen border intersection is an urgent problem to be solved to increase the reliability of test results. By employing the finite element method and the shape optimization method, the boundary of the cruciform specimen is optimized, and the mathematical expression of the shape function at the intersection of the cruciform specimen’s boundary is obtained. Furthermore, experiments are used to validate the optimum border. The findings indicated that the stress concentration at the improved specimen’s boundary was reduced. The optimal shape of the cruciform specimen’s boundary intersection described in this study can be used as a reference for the structural design of the cruciform specimen and can be used for extensive strain testing of the cruciform specimen.