bluuebunny/crossref_metadata_2025 huggingface dataset:
Monomolecular decomposition of C3F7I and CF3I: Theory meets experiment
Authors: Bystrov N S , Emelianov A V , Eremin A V , Loukhovitski B I , Sharipov A S , Yatsenko P I
Published: July 2020

For the first time, the rate constant of the thermal monomolecular decomposition of n-C3F7I in Ar was measured directly using the technique of atomic resonance absorption spectroscopy on a resonant line of iodine atom. Experiments were conducted behind the incident and reflected shock waves in a broad range of thermodynamic parameters (T = 800–1200 K and P = 0.6–8.3 bar). Experimental data were found to conform reasonably to the results of the Rice–Ramsperger–Kassel–Marcus theory master equation modeling based on the results of quantum chemical calculations. The obtained low- and high-pressure limiting rate constants for n-C3F7I and CF3I dissociation in Ar were reported. Third body efficiencies for Kr were also evaluated.
Damping properties of a two-phase mixture of transformer oil with gas bubbles
Authors: Gadzhiev M Kh , Tyuftyaev A S , Demirov N A , Akimov P L
Published: July 2020

In recent years, gas–liquid media are of interest due to their damping properties, which may be sufficient to prevent the mechanical destruction of the oil-filled equipment in consequence of electrical breakdown. For this purpose, an experimental installation was created, where the classical method of electric explosion of a wire is used to study the damping properties of a gas–liquid mixture. Microbubbles with a diameter of 1 mm and 0.5 mm were generated with a tangential air supply in a narrowing part of the Venturi tube or using a Laskin nozzle, respectively. Studies have shown that when the oil is aerated with 1 mm bubbles, final waves amplitude, decreases almost by 5 times, and when gassing with 0.5 mm bubbles the amplitude, decreases by more than 10 times. The attenuation of the amplitude of the pressure wave by a factor of the Euler number e in pure oil occurs in ≈ 7 ms, the bubbles with a diameter of ≈ 1 mm lead to an attenuation in ≈ 5 ms, and the bubbles with diameter of ≈ 0.5 mm in ≈ 2 ms.
Vacancions in the two-dimensional Wigner crystal
Authors: Bisti V E
Published: July 2020

From a new point of view, the recombination of two-dimensional electrons enclosed in a MgZnO/ZnO heterojunction with localized holes in the valence band is considered. It is suggested to consider quasi-holes in the two-dimensional electron system as quasiparticles in the Wigner crystal. The quasiparticles corresponding to electrons removed from the Wigner crystal are vacancions. Because of quantum tunneling effect, they are not localized. The vacancion energies E(k) form a band of width D which is proportional to the vacancy tunneling probability. The width D corresponds to the photoluminescence band of the two-dimensional electron system. The shape of the photoluminescence band of the Wigner crystal is considered within the tight-binding approximation for dispersion E(k) and compared with the experimental results.
The wide-range model of shell effects in hot plasma with semiclassical approximation for bound electrons
Authors: Dyachkov S A , Minakov D V , Levashov P R
Published: July 2020

The state-of-the-art density functional theory (DFT) methods provide high quality data about materials properties at extremes. The cost for this is the days of modern supercomputers operation to obtain a set of particular points on a phase diagram. Moreover, the low density region is usually unreachable for these methods due to convergence issues. We demonstrate that an adequate wide-range model of electron subsystem may be constructed using the simple Thomas–Fermi approach corrected by introducing semiclassical bound states instead of continuous ones. The obtained thermodynamic properties are compared to Saha and Kohn–Sham DFT data with good agreement thus covering the region between low and normal densities of hot plasma.
One-dimensional continuum model of two-phase flows in porous media
Authors: Zakharov S A , Pisarev V V , Chudanov V V
Published: July 2020

We present analytical and numerical description of two-phase flows in a porous medium for one-dimensional case. This research is aimed at modeling of natural gas condensate flows at hydrocarbon reservoir conditions. The model is component-scalable, uses generalized cubic equation of state and assumes equal pressures in coexisting phases. It can be used for miscible and immiscible fluid in a unified way. First results for binary mixture flows of alkanes are provided including self-oscillatory regime.
S- and p-polarized reflectivities of strongly correlated plasma
Authors: Zaporozhets Yu B , Mintsev V B , Reinholz H , Röpke G
Published: July 2020

An analysis of the response of a dense plasma to electromagnetic waves of moderate intensity can be used as a tool to study the validity of physical models describing the behavior of matter in extreme conditions. Within this work, the new experimental data are presented on oblique incidence of polarized electromagnetic wave. The study of polarized reflectivity properties of nonideal xenon plasma was accomplished using laser light at νlas = 2.83 × 1014 s−1. The measurements of polarized reflectivity coefficients of explosively driven dense plasmas have been carried out at incident angles up to θ = 70° for plasma density ρ = 1.8 g/cm3. The simple model of the ionization kinetics of the plasma transition region is considered.
Localization of active particles in chain structures in a direct current discharge under external influence
Authors: Kononov E A , Vasiliev M M , Petrov O F
Published: July 2020

We present the results of the analysis of the trajectories, dynamic entropy, and root-mean-square displacement of moving copper particles in a cluster of chain structures when exposed to laser radiation. We have revealed that the dynamics of the particle motion in the cluster corresponds to three modes: motion in a localized area, Brownian motion, and combined directional chaotic motion. The results of the analysis of linear displacement along and across the direction of motion of dust particles at various values of the laser radiation power are presented. It has been shown experimentally that copper particles are active Brownian particles and their activity grows with increasing laser radiation power, leading to a structural phase transition with the exchange of chain fragments within the cluster.
Plasmas and dusty plasmas at temperatures of liquid helium
Authors: Boltnev R E , Vasiliev M M , Petrov O F
Published: July 2020

Recent studies of dusty plasma structures formed by polydispersed CeO2 particles in a dc glow discharge at a temperature T > 1.6 K were shown to be the first experiments on dusty plasma in an exotic dark glow discharge mode. The properties of cryogenic helium plasmas at T ~ 1 K are summarized and discussed.
Anharmonic oscillations of the single dust particle trapped in a standing striation
Authors: Kartasheva A A , Golubovskii Yu B , Karasev V Yu
Published: July 2020

The nonlinear features of the vibrational motion of a single dust particle trapped in a standing strip are investigated. The excitation of the nonlinear oscillations with the large amplitude of the order of 1.5 mm is due to the periodic movement of the standing striation caused by the square-wave modulation of the discharge current. The frequency responses are investigated depending on value of the modulation depth. The anharmonic effects of the dust particle oscillations such as parametric instabilities and hysteresis are obtained. The theory of the anharmonic oscillator provides a good quantitative description of the experimental data. The values of the thresholds of excitation of parametric instabilities, the anharmonic coefficients and the critical values of the oscillation amplitude for the hysteresis are calculated. The potential energy curve of the single dust particle trapped in the striation is calculated using the values of anharmonic coefficients.
The origin of plasma jets generated in Z-pinch discharges
Authors: Vikhrev V V , Baronova E O
Published: July 2020

The results of modeling in the framework of magnetic hydrodynamics (MHD) for the development of a plasma jet in Z-pinches are presented. It has been shown that plasma jet origin is associated with the development of MHD instability m = 0, but not with the conical current sheath structure. MHD modeling is also carried out for θ-pinch systems where generation of plasma jets is much less effective. The corresponding analysis is presented.
Factors Affecting the Occurrence of Suspected Contact Dermatitis in the Traditional Fishery Processing Area (PHPT) of Muara Angke
Authors: Nawangsih Frida Ayu , Nugrohowati Nunuk , Harfiani Erna
Published: July 2020

Contact dermatitis is considered trivial for some people. There are many environmental factors could be the main factors causing contact dermatitis on salted-fish processor in Pengolahan Hasil Perikanan (PHPT) or Fishery Processing Area of Muara Angke such as water, temperature, fish, and humidity. These were due to the geographical location of the coastal determine the environmental factors which related to the contact dermatitis suspected on salted-fish processor in the PHPT Muara Angke area. The study was analytic observational with cross sectional design, with subjects were 112 samples. Results showed that 53,6% of salted-fish processor were suspected contact dermatitis. The suspected contact dermatitis increased by poor length of contact (OR= 9.42, 95% CI= 2.91 to 30.53, p=0,000), poor frequency of contact (OR= 4.70, 95% CI= 1.10 to 20.20, p=0,000), and bad temperature (OR= 3.74, 95% CI= 1.34 to 10.45, p=0,003). The length of contact can makes the lack of permeability of the skin, so the material of irritant can infiltrate properly. To prevent contact dermatitis the distribution of clean water must be comprehensive and do as the standards. The building of the processing room has to protect the worker from the heat temperature. Personal hygiene and personal protective must be increase to protect the worker from disease and to keep the quality of the product.
Desirable Ecotourism Plan for Pulau Ubin in Singapore, towards sustainable development to support Singapore tourism industry
Authors: Nugrohowati Nunuk
Published: July 2020

Introduction. Over the past 20 years Singapore people’s awareness to the heritage and ecological conservation issues had become more intensive. The people had understood what they should left for the next generation just the biodiversity conservation, so it was a good idea to conserve it from now on. Then on 20th of Desember 2001 the Ministry of National Development had decided to defer the land reclamation works at Pulau Ubin and had retained the rustic island as the nature state. The promoting Pulau Ubin for ecotourism afterwards was the most important step. Some works must be planned in order to succeed the ecotourism, promoting conservation areas as well as of supporting the local communities. Objective. To discuss about desirable ecotourism plan for Pulau Ubin in Singapore. Methods. The research methodology was explorative descriptive qualitative. Data collection methods had used interviewing technique with purposive sampling, observation technique and documentation on various secondary data related. Results. Singapore had some natural resources in Pulau Ubin among others large granite crops, the diversity of habitats on the island which is from sandy and rocky shores to mudflats, from mangrove swamps to ponds. The older regenerated mangroves stand on pulau Ketam while the largest areas spread around Sungei Besar and Sungei Batu Kekek. There is a close relationship between local communities and their rustic island as well as with the wildlife. The first Malay inhabitants being mostly fisherman, lived right on the coasts while the first Chinese inhabitants being mostly quarry workers and shop keepers, lived further inland. Many plans had been arranged in which can be used as an input in order to arrange an ecotourism plan in Pulau Ubin.
Pipeline Corrosion Protection Simulation of Cathodic Protection Method Againts Electrochemical Potential Distribution
Authors: Avianto Egi S. , Prasojo Budi , Sepfriansyah A. Ega , Imron Ali , Wismawati Endah , Moballa Burniadi , Hamzah Faiz , Rossa A.N. Ayu
Published: July 2020

Corrosion protection is very necessary for all steel or other types of metal, especially in buried pipes (underground construction). Direct contact between pipe materials (Carbon steel) can accelerate the corrosion rate. This is the case with the 20 inch pipe project working on the pipe installation. Initially to prevent this type of corrosion was done cathodic protection, but the result of examination was proven that there was a leakage of the potential distribution protection to the ground. Therefore it is necessary to do a distribution protection simulation to get how many anodes (magnesium package) to meet protection needs. The anode distance simulation results on the distribution of potential are carried out with the following variations: distance of every 45 meters, distance of every 30 meters, distance of every 20 meters, and distance of anodes every 15 meters. Based on the simulation results it is found that the anode distance cannot meet the minimum protection (-850milli volt) except at a distance of 15 meters. Installation of anodes at a distance of 15 meters with each pair of distance of 4.9 meters proved that the simulation results have met the minimum potential for corrosion protection. So that it can be used as a reference for installation of anode spacing for pipe corrosion protection.
Design of Coal Handling System for Filling Bungker using PID Method in Coal PLTU
Authors: Sutrisno Imam , Sudibyo Rafidan Maulana , Widodo Hendro Agus , Rifai Moch. , Santoso Agus Dwi , Sri Wahyuni Anak Agung Istri
Published: July 2020

The process of filling bunkers at PT PJB UBJ O&M PLTU 1 east java Pacitan is very dependent on coal handling system. In the existing system is still dependent on human resources as an operator, of course, very influential on human performance. The level of the bunker is a major problem for the continuity of the combustion process in the boiler. To support productivity, the authors make an innovative coal handling system design and monitor the level conditions in the bunker by using the PID (Proportional Integral Derivative) controller method to determine the level in the bunker. After that the condition is sent to the micro controller which then commands the conveyor and coal plough. The conveyor itself is driven by a stepper motor and the coal flow is driven using a servo motor. For combustion protection, there is a temperature sensor and a water pump in the bunker to extinguish. The level in the transmitted bunker serves as input to the PID and then the filling process is carried out by the conveyor to meet the demand for the bunker level. The accuracy rate in this system is 97.8% of the input data level of each bunker through an ultrasonic sensor. To make it more optimal all the information in the visual studio display.
Analysis of PM2.5 Transport Routes and Potential Sources of Qingdao in Winter
Authors: Gao Hang
Published: July 2020

Combined the mass concentration of PM2.5 in Qingdao region, with TrajStat software and the data from global assimilation system, getting the result of airflow backwards trajectory altered every 24-hour in November 2019 in Qingdao. The chief factors influenced the mass concentration of PM2.5 in Qingdao are wind speed and humidity. With the condition of lower wind speed and higher humidity causing heavier pollution. The airflow clusters in Qingdao can be classified into six types by using TrajStat software, and researchers made a series of study over each airflow direction. They also found that the particle concentration in Qingdao was mainly disrupted by the emission emitted within Shandong province, while getting a slight possibility of disruption from remote areas.
Study on Larsen Steel Sheet Pile as the Deep Base Pit Support
Authors: Yang Yang , Liu Wanfeng , Hu Aiping , Yang Zhaoqian , Shen Dilun
Published: July 2020

The steel sheet pile, a material featuring good quality, easy construction, high durability and strong interchangeability, has few restrictions for projects, and is therefore widely used as the deep base pit support. However, the complexity and specificity of base pit supporting demands an appropriate method to install it, which is the prerequisite of project safety. To ensure the safety, the paper studied the deformation by force and stability of Larsen steel sheet pile. It found that both indicators meet the requirements. Larsen steel sheet pile can provide effective protection for the base pit with decent performance. Therefore, Larsen steel sheet pile should be advocated in projects alike.
Seismic performance evaluation of RC frames with uniform infilled walls based on adaptive CMS
Authors: Yanjun LI , Dagang LU , Zhenyu WANG
Published: July 2020

In the development of performance-based seismic engineering, the capacity spectrum method (CMS) has been widely used in seismic performance evaluation because of its merits of clarity in concept and simplicity in computation. The lateral force resistance of nonstructural components and the influence of bidirectional loading are usually neglected in current seismic performance evaluation. Three archetype reinforced concrete (RC) frames were designed according to current Chinese standards and three-dimensional finite element models accounting for infilled walls or not at different modeling fidelity levels were created. Influences of infilled walls and bidirectional loading on seismic performance of RC frames are studied by CMS based on adaptive Pushover analysis. Results show that uniform infilled walls significantly improve seismic performance of RC frames. The bearing capacity under bidirectional loading is less than that under unidirectional loading. And bidirectional loading makes influences of infilled walls become somewhat inefficient.
Testing on loess collapse of expressway subgrade reinforced by lime-soil compaction piles
Authors: Li Jingshuang
Published: July 2020

The engineering constructed on loess ground have been threatened by loess collapse upon water. In Western China a new provincial expressway now has been built on loess ground. The depth of the loess layer is more than 20 meters. The loess ground was improved by five methods to reduce the collapsibility. The reinforcement was then verified by various in-situ tests and further tests were made on laboratory to explore the effect of ground reinforcement by lime-soil compaction piles. The laboratory tests show the dry density has increased by nearly 20% and the main reason for the increase of shear strength is the increase of cohesion index by 27% when the internal friction is basically the same. The collapsibility coefficients at different depths are examined and concluded that the collapsibility has been notably eliminated. Conclusion is drawn that the expressway subgrade shall not be influenced by reinforced loess ground.
Finite element analysis of cold-formed thin-walled steel skeleton wall with rigid diagonal braces
Authors: Jiang Zhonghua , Zhang Zheng , Feng Ruoruo , Chen Duhai , Richard Asante
Published: July 2020

In order to investigate the shear resistance of cold-formed thin-walled steel skeleton wall under monotonic load, the finite element analysis of six walls was carried out to obtain the shear capacity of different walls and reveal the wrecking mode of the wall. The results show that the arrangement of rigid cross brace and rigid diagonal brace in the wall can significantly improve the shear resistance of the wall, the vertical continuous splay layout with two spans has the largest lifting range.
Wind-induced Dynamic Stability analysis of Derrick with Double Flat Arm
Authors: Li Wenbin , Dong Qi , Zhou Fang , Ma Chi , Liao Yun , Ju Yanzhong
Published: July 2020

In order to study the stability of a derrick under fluctuating wind load, the dynamic stability analysis is carried out to get the critical wind speed in dynamic instability. Considering the effect of the fluctuating wind, the mean wind speed in dynamic instability is 39 m/s. When the height of the derrick is greater than 80m, the wind-induced vibration coefficient value of time history analysis is greater than the calculation value of GB 50009-2012 code, the vibration coefficient should be raised for derricks with a height greater than 80m, and the wind-induced vibration coefficient of flat arms should be considered separately.
Research on PC Component Quality Risk Evaluation Based on Intuitionistic Fuzzy Analytic Hierarchy Process
Authors: Deng Haiwang , Liu Jing
Published: July 2020

In order to further promote the development of prefabricated buildings, enrich the theoretical knowledge of the quality risk research of concrete prefabricated components, from the perspective of total quality management, the risk factors are divided into 5 aspects: personnel, equipment, system schemes, environment and raw material factors. With indicators and related descriptions, a set of risk evaluation indicator system is established. Based on the intuitionistic fuzzy analytic hierarchy process, the index weights of various risk factors are calculated, and a comprehensive quality risk evaluation model is established. The effectiveness of the model is proved by an example analysis, and the corresponding quality control points are summarized, with a view to the quality management provides a reference.
Simulation and Experimental Analysis of the Temperature Field of Flow of Airport Snow Thrower Based on CFD Theory
Authors: Chen Zhenglei , Cai Wantong , Cai Liangcai , Cen Guoping
Published: July 2020

It is a hot issue for airport users and researchers to pay attention to the influence of the hot air flow generated by the hot blowing snow thrower on the durability and service life of the pavement. In order to clarify the influence of hot air flow generated by hot blowing snow throwers on the temperature distribution of airport runway, this paper studies the temperature distribution of airport runway under the action of hot air flow generated by hot blowing snow throwers by CFD simulation and design of field measurement experiments. The results show that the maximum temperature of the surface obtained by the simulation method is 554.21K, the limit temperature of the surface is 539.75K and the average temperature difference is 22.64K, which verifies the accuracy of the simulation model. In view of the research results, in order to promote the application of this type of snow thrower in the airport, it is necessary to verify whether the airport roadway can withstand the action of high temperature airflow of 539.75K.
Study on rapid ecological protection of rock slope
Authors: Aocun Yunming , Lv Yapin , Wang Qingan , Xia Tianwei
Published: July 2020

In recent years, with the construction of domestic infrastructure and mining of ore, a large number of bare rock slopes have been produced. Failure to protect these rock slopes in time will cause driver’s visual fatigue, water and soil erosion of rock slopes, and in severe cases, geological disasters such as rockfalls and landslides, which will block roads and affect traffic and pedestrian safety. Based on the above, this article puts forward two types of slope ecological protection methods: assembled rock slope ecological protection and cast-in-place rock slope ecological protection. This method can solve the rapid greening of high and steep slope, the weathering of the slope surface, the effect of the road capacity, and the improvement of the local small environment.
Physical and Mechanical Properties of Pisha Sandstone with Different Corlors in Ordos Plateau
Authors: Zhang Xia , Zhang Hong , Wang Zhonghan , Liu Haiyang
Published: July 2020

Pisha sandstone with different colors is widely distributed in Ordos Plateau, showing different engineering properties. Therefore, basic physical and mechanical properties of two kinds of common Pisha sandstones with different colors (purplish red and yellow) are studied through laboratory tests. Because of the capillary pressure in the soil, the Shear resistance of Pisha sandstone will increase first and then decrease with the increase of water content; when the water content is nearly saturated, the shear strength indexes of two Pisha sandstones are significantly reduced.
Parametric Design and Aesthetics of 3D Appearance of Ancient Buildings
Authors: Jianfeng Shi
Published: July 2020

Ancient architectural design refers to the conservation repair and reconstruction of cultural relics and buildings as well as the design of antique-style architecture. This paper involves using the component-assembly method to perform the architectural design of ancient Chinese wooden buildings by 3D parametric means, including the application of the design method that combines modern industrial serialized group design technology contained in the above means with the trade-off of ancient building modularization. The model can be disassembled and converted into 2D engineering drawings.
Research on the Impact of Population Outflow on the Economic Growth of the Three Northeast Provinces from the Perspective of Educational Dividend
Authors: Fan Xiaonan , Chi Bo , Sun Xiaocheng
Published: July 2020

With the continuous expansion of population outflow, the number of labour factors in the three Northeastern provinces has greatly reduced, which has unavoidably affected the economic growth of the three northeast provinces. Firstly, this paper analyzes the current situation of population outflow and economic growth in the three Northeastern provinces, measures the current education dividend in the three Northeastern provinces on the basis of the definition of the connotation of education dividend, and according to the empirical analysis of population outflow on the economic growth of the three Northeastern provinces, makes countermeasures and suggestions on the impact of population outflow on the economic growth of the three Northeastern provinces from the perspective of education dividend.
Research on the Modeling of Optimal Allocation of Engineering Machinery Groups for Road Emergency Maintenance
Authors: Du Maoqiang , He Xiaohui , Wang Qiang , Wang Shanglong
Published: July 2020

To solve the problem of allocation to various places of engineering machinery groups for road emergency maintenance, the characteristics of emergency maintenance were analyzed and the emergency maintenance process queue network and Petri net model were built to simulate the emergency maintenance process. Then the calculation method of maintenance time was put forward, and the mathematical model of optimal allocation of engineering machinery groups for road emergency maintenance is established, which provides the basis for solving the optimal allocation scheme of the engineering machinery groups.
Development and application of pumping unit monitoring system based on wireless dynamometer sensor node
Authors: Luo Wang Zhinan , sheng Yin , Sujun Yang , Shihai Hua , Demin Chen
Published: July 2020

For the problems of the complicated installation and removal of dynamometer card detection equipment, high cost, not convenient for real-time detection, prone to failure and maintenance workload, a kind of low cost wireless dynamometer is developed. With the implement of wireless transmission gateway, comprehensive monitoring software is programmed. This system consists of a pumping dynamometer, gateway, monitoring software and indicator diagram measuring algorithm. Finally, the wireless dynamometer was installed at RenQiu oil field, and the data shows that the system works well and can be used for the long-term working and operating state of pumping oil field monitoring.
Application of Multi-group Seam Thickness Prediction in CJT Coal Mine
Authors: Rui Shan
Published: July 2020

Accurate prediction of coal thickness is of great significance to guide coal mine safety production. Taking the coal thickness prediction of the CJT coalfield in shaanxi province as an example, this paper selects the conventional wave impedance inversion technology and seismic multi-attribute technology to comprehensively predict the thickness of the target coal seam, and the correlation coefficient of the prediction trend of the coal seam thickness is as high as 98%. The prediction results show that wave impedance inversion combined with multi-attribute quantitative prediction of coal seam thickness is an effective method for complex geological conditions in the study area.
Study on mechanical properties of SMA silk
Authors: Yue Chuanyun , Yang Nan , Feng Yanzhong
Published: July 2020

Bond-slip constitutive relation between shape memory alloy wires and concrete is a comprehensive reflection of the bonding properties and it is relevant to crack width, plastic hinge rotation capacity, shear failure and theory analysis of nonlinear finite element. It has important significance of the numerical model of bond-slip of shape memory alloy concrete structure to the theoretical analysis and actual design. However, it is still in the exploratory stage of the constitutive relation between these two materials at home and abroad. This paper made the following research: Mechanics performance test of SMA. Differential scanning calorimetry test were used to get the heat transfer rate and temperature relationship diagram of the SMA wires, so the phase transition temperature of SMA was determined. On the basis of this, pull-out test was carried on to know the mechanical properties of the SMA wires.
The Hamiltonian Theroy in Viscoelastic Computations
Authors: Zhang WX , Yang LM
Published: July 2020

The Hamiltonian system approach is usually applied to derive the general solutions of the governing equations using the dual variables, by which the orders and dimensions of partial differential equations can be reduced effectively. However, its application is seriously confined to the problems with regular boundaries of a single material due to its analytical property. Due to the existence of energy dissipation, viscoelastic problems belong to non conservative systems, so Hamiltonian system method can not be directly applied. In this paper, the Laplace transformation method is used to transform the basic equations into the form of elasticity, and then the Hamiltonian system method of viscoelasticity is established.
Research on the Planning and Design of Sports Characteristic Town Based on the Integration of “Human Culture in Industry City”
Authors: Zhang Huili
Published: July 2020

With the development of economy, sports towns in China have developed rapidly in recent years, but a series of problems have appeared in the process of development. This paper analyzes the main problems existing in the planning and design of the sports characteristic town, and studies the Countermeasures of the planning and design of the sports town from the perspective of the integration of “human culture in industry city”, in order to promote the sustainable development of the sports town.
Analysis of Climate Comfort for Tourism in Kunming under Background of Healthy Living Destination
Authors: Wang Yanfang , Li Xiaolong , Cheng Xiping
Published: July 2020

Climate comfort is an important index for evaluating the liveability of a region, and it is also the basis for building a healthy living destination. Quantitative analysis of tourism climate comfort index was built in this paper through average temperature, relative humidity, wind speed and other climatic factors in Kunming, using Fuzzy Analytic Hierarchy Process to evaluate the tourism comfort of Kunming. The results show that Kunming has a pleasant perennial climate, a long tourism cycle and a great advantage in tourism climate comfort. The conclusions can provide scientific basis for the related work of healthy living destination.
Application of Diversion Construction Technology in Hydraulic Engineering Construction
Authors: Tao Zhang
Published: July 2020

Since the reform and opening up, China’s various construction undertakings have developed rapidly, especially the water conservancy engineering undertaking. As a basic industry for national economic development, it has achieved leapfrog development. Water conservancy projects play an important role in the development of China’s industry, agriculture and people’s daily life, it can promote the development of production and life, and improve people’s quality of life. Diversion construction technology is a widely used and important construction technology in basic water conservancy projects. It can reduce the impact of water flow during the construction process by using related technical measures, while ensuring the quality of water conservancy projects and improving the construction efficiency of the entire project. And other aspects have played an important role that cannot be replaced. This paper started with a brief description of diversion construction technology, and then studied the application of diversion construction technology in water conservancy projects.
Analysis of Influence of Glazing Systems on Indoor Environment of a Passive Solar Building in Lhasa
Authors: Gou Wenshi , Su Hua
Published: July 2020

Solar energy, which is inexhaustible and clean, has been widely used in passive or positive manners. A well-constructed passive solar house can improve the indoor environment and save energy of mechanical systems. Design of glazing system plays a vital role in passive solar buildings. This paper analyses influence of glazing systems on indoor environments of a passive teaching building in Lhasa, southwest on the Tibetan Plateau, China, for the purpose of optimizing retrofitting its windows. In this project no HVAC system is used, so indoor temperature is the main factor for evaluating the performance of different glazing systems. Four glazing systems were compared by computing uncomfortable hours and net heat addition of windows, using DesignBuilder. Economy is compared as well. Results show that single lowe clear 3mm (e=0.2) glazing leads to the most comfortable indoor environment in this project. Net heat of windows and comfortable rate are suggested to assess the overall performance of glazing systems. Generally speaking, we can’t use SHGC or U-Value to determine the best glass system only in the actual situation. Careful simulation is necessary to obtain the comprehensive performance of windows in a passive solar building.
A Brief Discussion on Teaching and Scientific Research Innovation of Assembly Building Technology
Authors: Pan Hongke
Published: July 2020

Construction industrialization and assembly building are the trend of development in the future, but the current related assembly technology and level is still relatively lagging behind, and lack of scientific research. The talents in the field of assembly building is very scarce, far from meeting the needs of production and society. In view of the existing problems in the development of assembly buildings, combined with the experience of the author’s workplace, the author puts forward the specific plans and measures for personnel training and teaching reform by using the methods of investigation and summary analysis, and probes into the key technologies for scientific research and innovation of assembly buildings and the plans for carrying out the research. The reform research has a good effect in our practical application, and provides a reference for further research.
Discussion on Some Problems of Regulations and Standards of Coal Industry
Authors: Fan Xiaogang , Qin Hongmei
Published: July 2020

In order to ensure the safety and health of the coal mine safety production and personnel, the state had issued a variety of laws and regulations and industry standards. Coal mining enterprises must abide by these laws and regulations. However, due to the fuzzy or inconsistent conditions of individual clauses, these regulations and industry norms lead to various problems in the actual production practice of coal mines. Combining with coal mine production practice, several issues such as the definition of coal and gas outburst, gas drainage standards and pore pressure measurement in tunnelling face, this paper puts forward some suggestions on the revision of the rules and standards for the specific industries of coal mine, which will provide reference for the revision of the rules and standards in the future.
Experimental Study on Physical and Mechanical Properties of Mixed Filling behind Retaining Wall
Authors: Xiaoyi CAO
Published: July 2020

Through large-scale triaxial shear test and particle sieving test, the particle breakage characteristics and shear strength of mixed coarse-grained fillers behind a high filling wall in Guizhou Province were studied. The effects of mudstone content, particle gradation, relative density and stress state of coarse-grained mixed fillers on particle breakage and shear strength were analyzed. With the increase of mudstone content, gradation and relative density, the particle breakage rate decreases. With the increase of confining pressure and stress, the particle breakage rate of coarse-grained soil also increases. The shear strength cohesion increases first and then decreases with the increase of mudstone content, and the internal friction angle decreases gradually. With the improvement of particle size distribution and the increase of relative density, the cohesion and internal friction angle increase. At the same time, a multivariate non-linear regression model was established to synthesize the comprehensive internal friction angle. The predicted values were in agreement with the experimental data, and the optimum mixed packing parameters were selected.
Study on Mechanical Behavior of Viscoelastic Polymer
Authors: Zhang WX , Chen YG
Published: July 2020

Due to the energy loss in deformation process, the mechanical problems of polymer materials can not keep the energy conservation, and a series of calculation methods of elasticity can not be directly applied. In this paper, we find that the differential stress-strain relationship can be transformed into algebraic equation form according to the correspondence principle. That is, in the Laplace space, the viscoelastic problem maintains the conservation.
Simulations of corrugated steel bracing reinforing infilled RC frame: influence factors
Authors: Feng Ningning , Wu Changsheng , Li Jianfen , Huang Lei
Published: July 2020

Based on the experimental infilled reinforced concrete (RC) frames strengthening by corrugated steel bracing, finite element (FE) analysis is carried out to compare with experimental research. Hysteresis curves, envelope curves, stiffness curves and failure modes of the corrugated steel bracing are studied to reveal the structural performance. Corrugated steel bracing is designed to resist lateral load in reinforcing concrete buildings. The results show that the deviations of the yield loads between test results and simulation are 11.1 % (forward direction) and 9.17 % (backward direction); the maximum loads between test results and simulation are 9.09 % (forward direction) and 6.52 % (backward direction), respectively. Ten models are studied to considering the key factors of corrugated steel bracing. The results show that the stiffness and maximum loads (forward and backward) are improved as the thickness increases. The ductility is reduced as the thickness increases.
Application Scheme Of Fiber Bragg Grating Sensor In Prefabricated Building
Authors: Zhou Canzong , Yao Zhengmao , Hu Yongqi , Hu Ziyi
Published: July 2020

Prefabricated building has the advantages of low energy consumption, high resource utilization and fast construction speed, which is the key technology for the development and upgrading of the future construction industry. In this paper, based on the existing shortcomings of prefabricated buildings, as well as the characteristics of anti-electromagnetic interference and strong corrosion resistance of fiber Bragg grating sensors, an application scheme is proposed to improve the safety of prefabricated buildings by utilizing the stress detection functions of fiber Bragg grating sensors.
Research on a new-type caisson with conic ice resistant structure in wharf application
Authors: Bing Xiao , Peng Yun , Wang Guangfu , Shao Ruoli , Dong Meng
Published: July 2020

Wharf structure in frozen areas is easily influenced by the heavy ice load and therefore it is necessary to adopt anti ice strategy in wharf construction. The conventional ice resistant strategies generally include designing the structure by using the extreme ice load and using solid structures in the ice-affected parts, which make the structure investment cost high due to the large ice load. To resolve above problems, this paper proposes a new type of ice resistant structure, namely the round caisson with conic ice resistant structure. The structure can transform failure type of the flow ice from compressive failure to bending failure, which can greatly reduce the ice load and therefore the project investment. To validate the ice resistant effect of the structure, a comparation of the ice load of the proposed structure with non-conic structure is conducted by mathematical calculation, and this paper develops a physical model experiment considering the natural condition of Changxing Island Port Area. The results obtained from above experiments show that (1) the measured ice load obtained by model experiment is reduced, (2) and the ice load on the conic ice resistant structure is much smaller than that on the non-conic structure.
Enhanced photoelectric performance of GQDs anchored WO3 with a ‘dot-on-nanoparticle’ structure
Authors: Hu Jiaxin , Lei Yun , Yuan Mei , Lin Yuanyuan , Jiang Zicong , Ouyang Zhong , Du Peng , Wu Yuncui
Published: July 2020

WO3/GQDs-H composites were synthesized by a hydrothermal method using WCl6 as the tungsten source. Various analyses were conducted to investigate the composition, structure, morphology and performance of the composites. WO3/GQDs-H composites formed a special ‘dot-on-nanoparticle’ structure by anchoring GQDs on the surface of WO3. The lattice spacings of 0.34 and 0.386 nm were attributed to the (002) facets of GQDs and WO3, respectively. Compared to blank WO3, an obvious shift to higher value in the binding energy of W6+ and W5+ and a decreased ID/IG value in the Raman spectra could be observed for WO3/GQDs-H composites. The photocurrent value of hydrothermal synthesized WO3/GQDs-H composites achieved 1.56 × 10–5 A cm−2, which was obviously prior to that of blank WO3 and mechanically mixed WO3/GQDs. The result indicated that the hydrothermal process promoted GQDs as a conductive route to transfer photoexcited electrons and improve the photoelectric performance of WO3/GQDs in comparison to the mechanical mixture process.
Microstructure evolution and tensile property of a first-generation single crystal superalloy fabricated by laser melting deposition
Authors: Wang Guowei , Shen Xianfeng , Yang Jialin , Liang Jingjing , Zhou Yizhou , Sun Xiaofeng
Published: July 2020

Additive manufacturing (AM) of single crystal superalloys has got some progress in recent researches, but there are few reports on eliminating recrystallization or mechanical properties of single crystal superalloys by AM. In this work, single-crystal samples of SRR99 were fabricated at high temperature by laser melting deposition (LMD). Owing to the high temperature of substrate in the deposition process, recrystallization in the following heat treatment process was eliminated. The contrast sample of SRR99 was prepared by directional solidification, and the microstructure evolution during heat treatment and tensile property of deposited samples were analyzed. The results showed that the shapes of the γ′ phase became irregular after solution treatment in deposited samples. After a solid solution and aging treatment, the γ′ phase size is larger and the γ′ volume fraction is slightly lower in deposited samples than in the contrast sample. As a result, the yield and tensile strength of deposited samples are slightly lower than that of contrast samples, but the plasticity of deposited samples is better.
Identification of SARS-CoV-2 in a Proficiency Testing Program
Authors: Edson Daniel C , Casey Danielle L , Harmer Susan E , Downes Frances P
Published: July 2020

Objectives

At the onset of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in the United States, testing was limited to the Centers for Disease Control and Prevention–developed reverse transcription polymerase chain reaction assay. The urgent and massive demand for testing prompted swift development of assays to detect SARS-CoV-2. The objective of this study was to assess the accuracy of these newly developed tests.

Methods

The American Proficiency Institute sent 2 test samples to 346 clinical laboratories in order to assess the accuracy of SARS-CoV-2 assays. The positive sample, containing 5,175 viral copies/mL, was fully extractable with SARS-CoV-2 viral capsid protein and RNA. The negative sample, with 3,951 viral copies/mL, contained recombinant virus particles with sequences for targeting human RNAase P gene sequences.

Results

Of the laboratories submitting results, 97.4% (302/310) correctly detected the virus when present and 98.3% (296/301) correctly indicated when the virus was not present. Among incorrect results reported in this proficiency challenge, 76.9% (10/13) were likely related to clerical error. This accounts for 1.6% (10/611) of all reported results.

Conclusions

Overall performance in this SARS-CoV-2 RNA detection challenge was excellent, providing confidence in the results of these new molecular tests and assurance for the clinical and public health decisions based on these test results.
Impact of Viral Load Monitoring on Retention and Viral Suppression: A Regression Discontinuity Analysis of South Africa’s National Laboratory Cohort
Authors: Harlow Alyssa F , Bor Jacob , Brennan Alana T , Maskew Mhairi , MacLeod William , Carmona Sergio , Mlisana Koleka , Fox Matthew P
Published: July 2020

South African guidelines recommend repeat viral load testing within 6 months when human immunodeficiency virus (HIV) viral loads exceed 1,000 copies/mL. We assessed whether South African facilities follow viral load monitoring guidelines and whether guidelines improve HIV-related outcomes, using a regression discontinuity design in a national HIV cohort of 174,574 patients (2013–2015). We assessed whether patients with viral loads just above versus just below 1,000 copies/mL were more likely to receive repeat testing in 6 months, and we compared differences in clinic transfers, retention, and viral suppression. The majority (67%) of patients with viral loads of >1,000 copies/mL did not receive repeat testing within 6 months, and these patients were 8.0% (95% confidence interval (CI): 6.2, 9.7) more likely to receive repeat testing compared with ≤1,000 copies/mL. Eligibility for repeat testing (>1,000 copies/mL) was associated with greater 12-month retention (risk difference = 2.9%, 95% CI: 0.6, 5.2) and combined suppression and retention (risk difference = 5.8%, 95% CI: 3.0, 8.6). Patients with viral loads of >1,000 copies/mL who actually received repeat testing were 85.2% more likely to be both retained and virally suppressed at 12 months (95% CI: 35.9, 100.0). Viral load monitoring might improve patient outcomes, but most patients with elevated viral loads do not receive monitoring within recommended timelines.