bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of monitoring system for marine power station based on DSP
Authors: Li Neng , Wu Zhiliang
Published: September 2019

Based on the experimental platform of marine power station, the design of the collection circuit was presented and the electrical parameters such as voltage, current, frequency and phase were collected by taking digital signal processor (DSP) in type of TMS320F2812 as the core controller. As regards the site jamming signal existed in power system, the full-wave differential Fourier algorithm was applied to improve the sampling process. It could completely eliminate the DC component and suppress the aperiodic component, while obtaining the accurate fundamental component. Furthermore, the necessary conditions for establishing an effective monitoring system were provided. Combined with the touch screen in type of WEINVIEW MT8100i, the data monitoring and alarm display of the marine power station were realized. The designed data collection and monitoring system can be continuously and stably operated on the experimental platform, which verifies the feasibility of the design.
The Electrical and mechanical simulation and computer-aided geometric optimization of high voltage post-insulator based on RBF neural network and finite element method
Authors: Zhang Shiling
Published: September 2019

The High-voltage post insulators are widely used in power systems. The electrical and mechanical properties of post insulators are closely related to the operation stability of power system. Based on the three-dimensional finite element method (FEM), the mechanical and electrical properties of post insulator are modeled and analyzed. The results show that the maximum electric field strength of the insulator is located on the surface of the voltage-equalizing ring near the high voltage side, and the first principal stress maximum value of 150MPa is mainly concentrated on flange supporting side. The PSO-RBF hybrid algorithm is proposed to optimize nonlinear inversion structural parameters of the post insulator. The results show that the PSO-RBF neural network has good effect on the nonlinear fitting mapping of the original finite element calculation data, and the algorithm has good convergence. The mechanical and electrical properties of the post insulators and the configuration of the post insulator-related voltage sharing ring and shielding ring are obtained, which can provide the theoretical basis for the insulation structure design and fittings configuration of UHV and below post composite insulators.
Simulation study on commutation failure control and recovery of UHVDC with hierarchical connection mode
Authors: Wang Sichao , Wen Jun , He Dongshan , Geng Xiaohong
Published: September 2019

UHVDC transmission projects with hierarchical receivers are connected in series on the DC side. When a single voltage level of AC system fails, commutation failure may occur in both hierarchies of DC system, and the impact will be more serious when the electrical connection is strong. In the process of fault recovery, inappropriate control strategy will also lead to successive commutation failures. In this paper, a commutation failure control and recovery strategy based on real-time fault detection and determination is proposed. In view of the instantaneous faults of AC system, the starting time is determined according to the predicted results of commutation failure, so as to reduce the starting times and prevent the continuous commutation failure in the recovery process. When the single-hierarchy AC system is permanently severely faulted, the fault hierarchy is isolated and the non-fault layer operates normally. The PSCAD/EMTDC simulation model of an UHVDC transmission project is built. Instantaneous and permanent faults are set up to simulate. It is verified that the proposed strategy can effectively reduce the number of successive commutation failures and improve transmission reliability.
An approach for constructing the S-box using the CML system
Authors: Liu Liyan , Lei Zhiyi
Published: September 2019

We propose an approach for constructing S-box by using the CML chaotic system. The chaotic sequences produced by the CML chaotic system are used to permute and diffuse the elements of the S-box randomly. The obtained S-box has a strong randomness property due to the high dimensional feature of the CML chaotic system. We analyze bijective property, nonlinearity, strict avalanche criterion, outputs bit independence criterion, input/output XOR distribution and linear approximation probability of the constructed S-box. The experimental results show that the proposed approach for constructing S-box is effective.
Lens rim points stitching algorithm based coaxial alignment micro assembly
Authors: Zhang Heng , Ye Xin , Yu Xinhai , Shao Chao , Wu Feifei , Zhao Yijin , Wang Lei
Published: September 2019

Optical lens assemblies are used more and more widely, and assembly and alignment processes are key to affecting lens accuracy. Considering that the common way of assembling lenses was manual, the coaxial alignment for intermediate-scale parts was considered to be a good alternative, which could improve the accuracy of assembly effectively. But it was difficult to capture the full edge of the lens in one image because of the limit of the CCD camera field of view. To solve this problem, a rim points stitching algorithm was proposed, and the barrel and lens were imaged by the camera at three different position. After the rim points were extracted from the three images, all the rim points were stitched according to the position of the camera at three locations. The rim points stitched were fitted to two circles by using the least squares method. Finally, according to the adjustment algorithm, the adjustment amount of the lens with respect to the lens barrel was calculated. Experimental results showed that this method could align lenses with the diameter greater than 60mm. The technique has the potential to be applied in automated alignment of lens assemblies.
Research on unbalanced training samples based on SMOTE algorithm
Authors: Li Kai , Hu Yueli
Published: September 2019

In the classification tasks of deep learning, unbalanced data distribution of training samples is a serious problem. In this case, the deep neural networks will bias to the majority-class samples and can not learn data characteristics of the minority-class samples well, making it difficult to identify the minority-class samples. To improve the performance of deep neural networks on minority-class samples, this paper proposes a novel scheme based on SMOTE algorithm, which generates new minority-class samples to balance the training dataset. Compared with the traditional over-sampling operations commonly used in image classification tasks such as copying images simply, image flipping, color adjustment etc, our scheme generates new minority-class samples, which improves the features of minority-class samples and avoids the over-fitting problem in classification. The workflow of image preprocessing and SMOTE over-sampling operation are introduced in this paper. The selection basis of the network model and the comprehensive model indicators are also presented. Comparative experiments are performed by testing models trained respectively on unbalanced dataset and balanced dataset after SMOTE over-sampling operation. Results shows that the proposed scheme is feasible and effective to improve the neural network’s ability of identifying minority-class samples in classification tasks.
An embedded wide-band sensor for PD on-line monitoring of XLPE cable joint
Authors: Fu Fangda , Yang Xu , Cheng Lin , Wang Luliang , Zhang Jing , Pan Zijun
Published: September 2019

Monitoring partial discharge (PD) activities in the joint of cross-linked polyethylene (XLPE) cables has attracted much attention due to its extensive application and high fault rate. In this paper, we designed a wide-band sensor with simple configuration, which was embedded in the outer semi-conductive layer of the cable. Based on the analysis of circuit and antenna models, the structural parameters of sensor were determined, and it was found that the effective bandwidth reached up to 500 MHz. In addition, the sensor had a quick response to the pulse with a rising time longer than 2 ns by testing its square response, as well as a linear input-output characteristic and a sensitivity of 3 pC. At last, the sensor was applied to insulation defect type identification in the cable joint. As for three common defects, both the single PD pulse and PD patterns showed distinct. These indicated that the sensor had a potential application prospect in the PD online detection for cable joint.
A real-time gas turbine simulation model for control logic evaluation
Authors: Tao Ye , Pan Yining , Xin Xiaopeng , Xu Yunbing , Sui Yongfeng
Published: September 2019

During our development of a gas turbine control system, we need to evaluate the correctness and completeness of the control logic before conducting a hardware-in-the-loop (HIL) test. For this purpose, a pure software simulation framework which includes virtual DPU (VDPU) and gas turbine model interfacing through OPC protocol was proposed. A real-time gas turbine simulation model for this framework was developed. This gas turbine model was written in C++ and employs the object-oriented philosophy for maintenance and further development and it uses a non-iterative method to ensure the real-time capability to run simultaneously with the control logic. From the result of preliminary tests on this model, it shows to be able to simulate the response of real gas turbine to the instructions from the control system and suitable to evaluate the control logic.
A study on reducing power consumption of the centrifugal fan for the negative pressure adsorption wall climbing robot
Authors: Yang Yongkai , Zhang Hu , Song Qiuzhi
Published: September 2019

In order to solve the problems of ship wall climbing robot’s great power consumption and high noises, a new approach to reducing power consumption and noises of the centrifugal fan was investigated. Firstly, the relationship between the air volume of a centrifugal fan and ship’s dip angle of the outer wall is obtained by analyzing force condition of the robot and the theory of negative pressure adsorption. Furthermore, by means of researching the process of fan’s speed-regulation through changing DC 0-3.3 of fan’s driver. We get the relationship between speed-regulation voltage after D/A convert of fan’s driver and ship’s dip angle of the outer wall. We proposed a control system that can automatically detect ship’s dip angle of the outer wall and adjust the output power of the centrifugal fan. Finally, the result of reducing power consumption and noises was tested effectively.
Influencing factors of water recycle device in cooling tower of thermal power plant based on corona discharge principle
Authors: Zhang Mingkun , Wang Yinyi , Liu Jieyu
Published: September 2019

The water loss in the wet cooling tower of thermal power plants is serious. There is a lack of high-efficiency recycling method for water mist with a small particle size until now. Based on the principle of electrostatic deposition, this paper analyses the principle of water mist recovery based on corona discharge. The water recovery device based on corona discharge was designed. The equivalent flow model was used to calculate the ion flow field distribution in the device, and the influence of the size of the water collecting plate on the ion flow field was analysed. By using the finite element analysis (FEA), the influence of the shape of the water collecting plate and the structure of the discharge electrode on the electric field in the device is calculated. A device optimization program is proposed. The results of this study provide theoretical guidance for the recycle of water mist in thermal power plant cooling towers.
Comparison between suppressing approaches of very fast transient over voltages in gas insulated substation
Authors: Almenweer Reem A , Su Yixin , Wu Xixiu
Published: September 2019

Very Fast Transient Over-Voltage (VFTO), which is a unique electromagnetic transient phenomenon generated by SF6 gas discharge in disconnector gap in Gas Insulated-Substation (GIS), could bring damage to power devices, especially to power transformers. The peak magnitude and high-frequency oscillations of VFTO cause reduction of dielectric of gas insulation, high inter-turn voltages and internal resonance in the transformer windings. Due to all of these disadvantages related to VFTO, VFTO becomes a criterion to determine the insulation level of the GIS, and VFTO damping is rising as an essential issue to be solved. However, the researchers concern on finding the optimum technique for suppressing VFTO, this paper aims to discuss the most feasible methods for mitigation of the overvoltage magnitude of VFTO and determine the most efficient approach for VFTOs attenuation by presenting the advantages and disadvantages of each approach. In this review paper, some suppression methods of very fast transients in GIS are presented, including adopting a resistor-fitted disconnector, ferrite rings, surge arresters, and high-frequency resonator. The results show that the peak value of VFTOs can be decreased to a great level by employing the proposed damping methods. Finally, the best approach for the suppression of VFTOs is chosen based on deep discussion for each method with its features.
Design of a greenhouse remote measurement and control system based on internet of things technology
Authors: Xiao Yufeng , Zhang Zhixia , Wang Yonggang , Zhu Kai
Published: September 2019

This study designed a greenhouse remote measurement and control system based on Internet of Things technology. The system is based on WebOP Designer configuration software and Modbus communication protocol, with Adam4060 relay output module and intermediate relay as the control core. Remote monitoring of the greenhouse environment is achieved through cooperation with the greenhouse environmental data acquisition sensor, the Adam-4117 analog input module, the industrial-grade programmable human-machine interface, the internet/intranet and the Web Access web database. Local customers can view real-time data and historical curves by operating the human-machine interface, and control the operation of each actuator in the greenhouse according to the alarm status and warning line settings. The remote client can log in to the webpage database through the PC client and the mobile client conveniently and quickly. The system is beneficial to reduce labor costs and improve the informationization level and management efficiency of agricultural production. Through the access of expert systems, precise control of crop growth environment is achieved, and the economic benefits of crops are improved.
Research on remote calibration and online monitoring system of electric energy metering device
Authors: Yang Lu , Zhang Dingqu , Lin Guoying , Song Qiang , Meng Qingliang , Pan Feng , Liu Chang
Published: September 2019

This paper introduced research on remote calibration and online monitoring system of the gateway electric energy metering device. The function combined with composition of the station’s remote calibration-monitoring device and the master station management platform are emphasized. The system integrated the ways of multi-channel synchronous remote calibration, multi-dimensional monitoring, intelligent switching of detection and calibration loop, self-test of detection unit and so on into the complete set, cooperated with the master station management platform, to realize remote calibration, online monitoring, fault diagnosis and state evaluation of the gateway electric energy metering device. The system innovatively adopts a multi-channel synchronous remote calibration method to realize intelligent switching of detection and calibration loops. Through multi-dimensional data detection and state evaluation algorithms, it is possible to more comprehensively detect device status and achieve fault diagnosis. In addition, the system has high stability, accuracy and flexibility. The research plays an important role in reducing the operation-maintenance costs of the gateway electric energy metering device, guaranteeing the safety of operators and improving the level of operation and management, which ensures the accuracy of gateway energy metering and the fairness of both parties in power trade.
Research on simulation technology of power system operation and dispatch control based on trend tracking
Authors: Zhao Min , Ding Ping , An Ning , Zhang Yong , Zhang Lei
Published: September 2019

Over the past decade, Chinese energy structure and power system technology have undergone tremendous changes. First, the proportion of new energy in power generation capacity is increasing, and the permeability of some areas has reached 30% - 50% of the total power generation capacity; second, the characteristic of power electronics in power system is becoming more and more obvious. The impact of these two aspects on the power system is that the power fluctuation of the power grid is intensified, and the power flow is flexible and changeable, which brings new challenges to the operation scheduling and simulation technology of the power system. Therefore, based on Power System Analysis Synthesis Program (PSASP) electromechanical transient simulation program, this paper studies and proposes a power grid regulation and control analysis method, it can help the dispatchers and operators to improve the dispatching plan and the accuracy of various kinds of anticipated faults. This method seeks to simulate the power flow fluctuation of the real power grid approximately. The validity of the proposed method is verified by the simulation calculation of some year national interconnection data.
Fast and accurate 3D reconstruction based on grating projection
Authors: Ou Ji , Yang Haima , Liu Jin , Xie Mengtao , Xu Wei
Published: September 2019

The principle model and calibration method of measurement are very important to the measurement system. In the vision measurement system, the auxiliary light source, such as laser, interference light, sine grating and so on, is usually needed in order to achieve high precision measurement results. In the existing 3D measurement methods for the surface topography of complex objects, in order to complete the measurement of absolute phase, it is usually necessary to process at least 6 fringe images, which limits the measurement speed. A method for obtaining the 3D shape of an object by using four sinusoidal fringes is presented. The truncated phase of the sinusoidal fringe is obtained by using the four-step phase shift. When the fringe order is obtained, the time of data processing can be reduced and the measurement speed can be further improved. The reconstruction time is less than two minutes and the maximum absolute error and maximum RMS error are 0.033mm and 0.029mm respectively when the height of the face model is 45mm. The validity and practicability of the method are verified, and it has a wide application prospect in high-speed and real-time 3D measurement of complex topography.
Fast-transient high-performance low dropout regulator with push-pull technique
Authors: Duan Zhikui , Zhao Xiaomeng , Li Qiushi , Niu Guo , Hu Jianguo , Wang Xiucai , Chen Jianwen , Wang Xingbo
Published: September 2019

A fast transient response low dropout (LDO) regulator based on push-pull structure is presented in this paper. The push-pull circuit sampling the output of the LDO and adjusting the gate voltage of the power MOSFET by push-pull current. The slew rate of the power MOSFET gate is accelerated and the transient response performance is improved. With a 1μF decoupling under 180 nm CMOS technology, the proposed LDO exhibits an excellent transient performance. When the workload changes steeply between 100μA and 20mA in 100ns, the overshoot is 10.176mV and undershoot is 10.795mV with the recovery time are 1.272μs and 0.888μs respectively.
Selection of optimal coordination contract for sustainable supply chain under carbon tax
Authors: Deng Kexin , Gao Benhe
Published: September 2019

The purpose of this paper is to find an optimal coordinating contract on a two-echelon sustainable supply chain composed of a manufacturer and a retailer under carbon tax policy. Taking consumer environmental awareness (CEA) and manufacturer’s abatement investment cost into account, this study compares wholesale price contract, revenue-sharing contract and green cost-sharing contract, and finds that none of them can obtain coordination. Then, “Adjusted” contracts are introduced and proved that only adjusted revenue-sharing contract can coordinate the supply chain. Considering the profit redistribution proposition of the two-part tariff contract, the study introduces combined contracts, which are found capable of obtaining supply chain coordination as well as a win-win outcome.
An assembly process parameters optimization method for precision assembly performance
Authors: Shao Chao , Ye Xin , Wang Lei , Zhang Zhijing , Zhu Dongsheng , Qian Jiahui
Published: September 2019

There are only few works in literature that suggest an assembly process optimization method based on manufacturing errors in the precision manufacturing area. A multi-objective assembly process parameters evaluation and optimization method for precision assembly performance of microstructures with manufacturing errors has been proposed in this paper. Based on the model with manufacturing errors, the ABAQUS software is used for simulation and calculation, and the assembly performance evaluation indexes of the microstructures under different assembly process parameters, such as stress value, stress distribution value and pose offset, are obtained. The mapping model of the key assembly process parameters and assembly performance is established based on BP neural network. Finally, the best assembly process parameters for the optimal assembly performance are solved based on the genetic algorithm, and the method has been verified by the optimization results of preload forces of the 3D mechanism, which can be used to guide and monitor the assembly process quantitatively in the precision manufacturing area.
Study on measuring straightness of piston rod in large oil cylinders
Authors: Chen Xinchun , Bi Mengxue , Xue Chunyang
Published: September 2019

The straightness detection methods of different geometric elements are described in detail in GB/T 1133 6-2004, but there are still many difficulties in how to implement the method in engineering, for example, how to detect straightness in the production process of piston rods in large oil cylinders. Based on time-domain three-point method and the various requirements of straightness measurement in the process of large piston rods’ production, a method for detecting the straightness of the large rod with large length-to-diameter ratio was proposed and the measuring device was successfully developed. In addition, the influences of the three error sources including axial rotation angle, probe spacing and sampling interval on the measurement results are discussed in detail. Considering the production cost and the accuracy of the device, the parameters of the straightness detection device are optimized. The effectiveness of the method was verified by field experiments. It’s very important that the study provides a technical basis for the straightness detection of large slender rods.
Penetration control of GTAW process for aluminum alloy using vision sensing
Authors: Peng Guodong , Gao Yanjun , Tian Zhijie , Yang Zhanli , Xue Boce , Hong Yuxiang , Du Dong
Published: September 2019

Unpredictable and inevitable perturbations during welding have adverse effects on the uniformity of weld penetration degree. Hence feedback control of weld penetration is necessary for assuring the welding quality. The backside weld bead width, regarded as a representation of penetration state, is measured usually by a structured-light sensor during the welding process. However, the structured-light method can only measure the width of the solidified weld behind the weld pool, but not the weld pool width, owing to the specular weld pool surface, thermal radiation and the possible arc light. It will introduce a time delay into the penetration control system. A novel low-cost visual technique of acquiring the backside weld pool width is developed in this paper, and the closed-loop control of weld penetration is achieved during gas tungsten arc welding (GTAW) for aluminum alloy. The parallel light is projected onto the weld pool backside, and the outline of the weld pool is highlighted because of the different reflection from the plate’s flat surface and the weld pool’s convex surface. Changes in the plate geometry are introduced during the experiments to perturb the welding process. Results show that stable penetration is maintained despite the perturbation.
The research of effect of various parameters on processing performance of compound machining of EDM milling and arc machining
Authors: Niu Zhenwei , Liu Yonghong , Wu Xinlei , Zhang Xuexin , Ding Zhiwei
Published: September 2019

As a new processing method for hard-to-cut materials, compound machining of EDM milling and arc machining has the extremely high processing efficiency. The study of machining parameters is indispensable to the research of the process performance. In this paper, a large number of single factor experiments under different processing parameters were carried out by using compound EDM arc milling machining technology. The effects of different peak current, arc pulse duration, arc pulse interval, spindle speed and the external diameter of the electrode on processing efficiency, the surface roughness(SR) and relative electrode wear rate(REWR) were obtained. More importantly, different optimal parameters to get the highest processing efficiency, minimal SR and REWR were also acquired to provide support for future research.
A hybrid artificial bee colony algorithm for balancing two-sided assembly line with assignment constraints
Authors: Xiong Jing , Duan Xiaokun , Wang Erhua
Published: September 2019

Two-sided assembly line balancing problem (TALBP) is a vital design problem for the industries. In real production process, some complex constraints should be considered in the two-sided assembly line. To solve the practical TALBP, this paper proposes a hybrid algorithm (HABC) that combines the artificial bee colony (ABC) algorithm and late acceptance hill-climbing (LAHC) algorithm. In the proposed algorithm, a well-designed decoding scheme is embedded to tackle multiple assignment constraints. Moreover, two neighborhood search strategies are implemented by employed bee and onlooker bee to explore and exploit the new solution. A set of computational experiments is performed on benchmark problems. The comparison results, best solutions, standard deviation and relative percentage index demonstrate that the HABC algorithm outperforms other algorithms published in the literature and finds 5 brand new solutions for 15 instances.
Application of high-speed cutting technology in automobile manufacturing
Authors: Hao Botao , Lin Guomin
Published: September 2019

High-speed cutting technology is widely used in stamping die, die-casting die and injection die for its high processing efficiency. Based on the characteristics and advantages of high-speed machining technology, this paper analyzes the application of high-speed machining technology in the manufacture of automobile parts, overlay parts, cylinder bodies and automobile wheels, taking the change of cutting speed and cutting temperature as the research object.
Nature Based Solutions (NBS) for sustainable and resilient cities: experiences from Europe and Brazil
Authors: Antuña-Rozado C. , Herzog C. P , Freitas T. , Cagnin C. , Wiedman G.
Published: September 2019

Although Nature-Based Solutions (NBS) is a relatively recent concept, it can provide effective means for cities worldwide to become more sustainable and to enhance urban resilience, thus improving the quality of life of their citizens. Moreover, cost-effective NBS can help improve the urban environment in multiple scales, from buildings to neighbourhoods, from public spaces to peri-urban areas, providing all kinds of co-benefits positively influencing the above-mentioned challenges. Depending on the context and the need, many different stakeholders may be involved in the co-creation of systemic, inclusive and locally attuned NBS supporting social cohesion and urban equality.

The learning alliance fostered by the EU-Brazil Sector Dialogue on NBS, is currently working together to identify common research and innovation agendas for cooperation, as well as mapping relevant examples of successful NBS that have been recently implemented or are under development in both Europe and Brazil. The cases selected have been studied and compared with a particular emphasis on their potential for replicability, scalability and adaptation to the local context. In addition, they should address the three pillars of sustainability: environmental, socio-cultural and economic.

Therefore, this paper discusses the opportunities offered by NBS (even in periods of economic downturn), but also the limiting factors hindering their wider dissemination. In addition, it will present through a few inspiring case studies from both regions, clear examples of successful implementation of NBS, which could be replicated and scaled in other locations in response to specific local conditions.
Mineral wool waste-based geopolymers
Authors: Yliniemi Juho , Luukkonen Tero , Kaiser Anne , Illikainen Mirja
Published: September 2019

Mineral wools –a general term for stone wool and glass wool– are the most common building insulation materials in the world. The annual amount of mineral wool waste generated in Europe totaled 2.3 Mt in 2010 – including wastes from the mineral wool production and from the construction and demolition industry. Unfortunately, mineral wools are often considered unrecyclable due to their fibrous nature and low density. Thus, the utilisation of post-consumer mineral wool waste in different applications remains low.

Mineral wools have a great potential as geopolymer precursors as they have suitable chemical and mineralogical compositions. As geopolymers can provide significant CO2 emission reductions compared to traditional Portland cement concretes, using mineral wool waste as geopolymer precursor would be an attractive utilisation path. Here, we show that mineral wool waste can be geopolymerised to form sustainable cements with good mechanical properties. Geopolymerisation of mineral wool waste therefore offers an attractive route for waste valorisation and production of low-CO2 cements.
Multidimensional evaluation of tenants’ temporal relocation during a renovation: A comparison between two case studies from Sweden.
Authors: Serrano-Jiménez A , Femenías P , Thuvander L
Published: September 2019

This research focuses on the tenants’ temporal relocation or stay in the home during renovation works and the property owners’ possibility to refurbish with intense and global interventions. The study compares two renovation strategies applied in two residential neighbourhoods in Gothenburg, Sweden, built between the 1950s and 1960s. In one neighbourhood, the tenants stayed in their homes during the renovation works, and in the other neighbourhood, the tenants were relocated to other buildings for over six months. Retrofitting interventions, investment costs, rent increase, time periods and the constructive processes are considered for each renovation strategy, as well as the impressions of the tenants and property owner entities in each neighbourhood were collected. The results compare, through a report on the affordability and effectiveness, the pros and cons of a relocation or non-relocation strategy. This research offers a real and experimental comparison that reach to political, architectural, social and economic conclusions to facilitate the decision-making regarding the tenants’ temporal relocation. Finally, it is also highlighted the need to involve the tenants in the design of effective renovation proposals.
Sustainable Transportation in Metropolitan Cities; Berlin, Helsinki, New Delhi and Pune
Authors: Rajesh S , Shashank P , Abhirup D , Tolu A , Zorro D , Zakarya A , Albo M
Published: September 2019

If one comprehends a city as a human body, then transportation would be its arteries and veins. It makes mobilization possible. In the age of rapid globalization transportation does not only concern itself with a single city but transportation deals with a global scale today. This paper focuses on a comparative analysis of transportation methods for four cities in terms of how new sustainable transportation concepts can be applied to make our future better. The discussion includes a vast range of possibilities of our future sustainable cities in transportation. Environmental and technological aspects as well as politics and policies are inspected. Cities flourish, develop and revolve around transportation. Our future sustainable cities would be no different. We need to approach transportation from all the three aspects of sustainability e.g. social, ecological, and environmental. We have chosen our cities for case studies on a broad range from low-density in Helsinki to very high population in Delhi. The rapid growth in transportation has remarkably increased the carbon footprints of our cities. While planning for our future cities making transportation sustainable is of paramount importance. To understand the issue of transportation for our sustainable cities we discuss the present state of transportation globally and analyse transportation in major cities such as Berlin, Delhi, Helsinki and Pune.
A sustainable built environment for healthcare: generative mechanisms for future-proofing
Authors: Krystallis I , Rickaby B , Murtagh N
Published: September 2019

Construction projects are planned from a set of deterministic objectives and constraints that dictates what designers must accomplish. In the case of healthcare facilities, where the policy environment is characterized by change on several fronts, fixed requirements could constrain their evolvability and sustainability. Future-proofing is a response to uncertainty whereby a physical structure is designed to respond to future changes in requirements, change of use, strategic perspectives, business drivers, new policies and changing climate. The paper investigates the causal powers that explain how and why future-proofing decisions achieve a sustainable outcome. A critical realist lens is adopted to develop a configurational perspective of future-proofing design evolution. Critical Realism’s open systems ontology of social reality can account for the fact that outcomes are not predictable and can better explain the nature of causation in complex social interactions such as construction projects. A case study research design was conducted comprising in-depth interviews with healthcare construction professionals in a UK setting. The study contributes to the sustainability literature by offering four generative mechanisms of future-proofing decision making and how they contingently lead – or fail to lead - to future-proof outcomes. Two change mechanisms and two problem mechanisms are presented, together with their configuration under the right conditions and context to lead to design decisions for construction projects capable of adapting to a range of possible futures.
Evaluation of hybrid heating systems with a combination of fossil and renewable energy sources
Authors: Borodinecs Anatolijs , Bogdanovics Raimonds , Prozuments Aleksejs , Tihana Jelena , Gaujena Baiba
Published: September 2019

Natural gas heating systems are traditionally very popular in private sector in Latvia because of their numerous advantages, such as high efficiency, relatively low CO2 emissions, automation possibilities and convenient fuel supply, as well as widely available natural gas distribution network. Household natural gas consumption has remained fairly stable over the last decade and accounted for 11.3% of total natural gas consumption in 2017, however, natural gas consumption may decline in the near future, because of installation of renewable energy powered systems which improve systems’ resilience and reduce expenses on heating and hot water preparation. Curently hybrid gas boilers in combination with solar thermal panels are promoted on the market as the most efficient and environmentally friendly solutions. The main aim of this study is to perform a detailed simulation on hybrid gas systems energy production in Latvian climate and to evaluate potential energy savings. The performed simulation results show that solar thermal panels do not actually reduce the consumption of natural gas in November, December and January, whereas in the summer months solar thermal panels almost entirely provide the needed energy to prepare hot water. Nevertheless, the annual savings for a single family house are minor and the payback time for the installation of hybrid gas/solar systems could exceed 20 years.
The main formative material of bay’s estuarial abrasion-accumulative jumpers and it’s interconnection with the lithological composition of Volgograd reservoir coasts
Authors: Baranova M S
Published: September 2019

The article contents results of the data compilation of lithological composition of Volgograd reservoir coasts. The interconnection between the main formative material of bays estuarial abrasion-accumulative jumpers and lithological composition of reservoir coasts was revealed. The principal differences between the material of bays jumpers and lithological composition on the right and the left coasts were determined in this research. An electronic thematic layer “The lithological composition of the coasts of the Volgograd reservoir” was created and the attribute table of this layer was filled. We determined that volumes of bays of the Volgograd reservoir decreased significantly from 1988 to modern time.
Precipitation in the catchment area of the Votkinsk reservoir: nature, type and temporal variability
Authors: Pischalnikova E V , Kalinin N A , Akilov E V
Published: September 2019

The type and nature of precipitation in the catchment area of the Votkinsk reservoir are considered with taking into account its hydrological zoning. Intra-annual frequency, duration and intensity of precipitation are shown. It is determined that 321 days are observed with precipitation per year on average. Daily amount does not exceed 1 mm. In the catchment area, widespread and rain precipitations are observed with a frequency of 51 and 53% respectively. The daily duration of precipitation depending on its type was obtained, which equals 4–6 h for rain and mixed precipitations and 8–10 h for solid precipitation. High precipitation intensity is observed in the northern part of the catchment area, where the terrain contributes to the development of cloudiness and an increase in precipitation intensity.
Trends of climate parameters over Tanzania
Authors: Mikova K D , Msafiri L C
Published: September 2019

Analysis of the climate parameters over Tanzania were done for period 57-61 years. Rainfall and wind speed had greater variability than air temperatures. Positive significant trend of dry air temperature, maximal and minimal air temperatures were detected almost for all weather stations. As well positive trends of wind speed were detected just for stations Dodoma, Arusha, Mtwara and Mwanza. While rainfall trend analysis just for station Mtwara showed negative significant trend. In absolute values wind speed increased by 0.7-1.1 m/s, rainfall decreased by 89.3-136.1 mm, dry air temperature rise up 0.5-1.0 °C, maximal and minimal air temperatures values have grown by 2.0-3.6 °C.
Geoecological evaluation of environmental damage to the results of long-term dynamics of benzopyrene and petroleum within landfill sludge
Authors: Dregulo A M , Pitulko V M , Rodionov V Z , Kulibaba V V , Petukhov V V
Published: September 2019

The article deals with the problems of environmental pollution with benzapyrene and petroleum products contained in sewage sludge. The dynamics of changes in the concentrations of benzapyrene and petroleum products in the soils of the object of accumulated environmental damage (landfill sludge) is analysed, the main criteria for the identification of environmental damage for these pollutants are determined.
Ecological state of the water objects in Perm Krai and prevalence of parasitic disease among the population
Authors: Dvinskikh S A , Zujeva T V , Kitaev A B
Published: September 2019

Perm Krai is a region with a high level of parasitic disease, which depends on the presence of natural focal points of infection, water pollution and social conditions. The article analyses the role of ecological state of water bodies and social conditions on the basis of population survey. It is confirmed that the pollution of water bodies is not a determinant factor of the spread of helminthiasis among the population. Social factors come to the fore.
Seasonal variation of methane flux from Mozhaisk reservoir
Authors: Grechushnikova M G , Repina I A , Kazantsev V S , Artamonov A Yu , Lomov V A , Lomova D V , Kremenetskaya E R
Published: September 2019

The paper present the results of methane flux measuring from the surface of valley type reservoir with a long water residence time. The factors of its spatio-time variations are revealed. The results of calculation and measurements of diffusive flux are compared.
Up-regulation of endometrial oxytocin receptor is associated with the timing of luteolysis in heifers with two and three follicular waves†
Authors: Domingues Rafael R , Ginther O J , Gomez-León Victor E , Wiltbank Milo C
Published: September 2019

Initiation of luteolysis in ruminants is variable due to ill-defined mechanisms. Cycles of two follicular waves are shorter and have earlier luteolysis than three-wave cycles. This study validated a cytobrush technique for evaluating dynamics of endometrial gene expression and associated changes in mRNA with timing of luteolysis, based on circulating progesterone and ultrasound-determined changes in blood flow and volume of corpus luteum (CL). On day 8 (ovulation = day 0), Holstein heifers were randomized into two groups: cytobrush group (n = 9) had an endometrial sample collected every 48 h from day 8 until end of luteolysis (CL blood flow ≤ 20%) and control group was sampled only once either before (day 12; n = 4) or at the end of luteolysis (n = 5). Concentrations of progesterone, CL blood flow, CL volume, and the frequency of two and three-wave cycles were similar between groups. Endometrial mRNA for progesterone receptors and estradiol receptors 1 and 2 was greater on day 8 and decreased thereafter similarly in two and three-wave cycles. Oxytocin receptor mRNA increased earlier in two vs three-wave cycles (day 14 vs 18), and the increase was associated with the onset of luteolysis. In conclusion, the cytobrush technique allowed in vivo collection of multiple endometrial samples during the estrous cycle. Endometrial mRNA expression of steroid receptors did not explain the variability in timing of onset of luteolysis in heifers while the later onset of luteolysis in three-wave cycles was associated with later up-regulation of oxytocin receptor mRNA.
Emergency Department Visits After Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis
Authors: Harris Andrew B. , Marrache Majd , Puvanesarajah Varun , Raad Micheal , Skolasky Richard L. , Njoku Dolores , Sponseller Paul D. , Jain Amit
Published: September 2019

Background:

The incidence of emergency department (ED) visits after posterior spinal fusion (PSF) in adolescent idiopathic scoliosis (AIS) patients is not well known. We hypothesize that the majority of ED visits are related to constipation and pain issues, and are not for serious complications.

Methods:

Using a private insurance claims database, we identified AIS patients aged 10 to 21 years who underwent PSF from 2010 to 2015. Patients were excluded for diagnoses of neuromuscular or syndromic scoliosis. ED visits that occurred within the 6-month postoperative period were identified. The diagnoses present at these visits were pooled and analyzed, in addition to insurance payments associated with these visits. Significance was set at P=0.05.

Results:

A total of 5934 patients met inclusion criteria. Mean age was 14.4±2.2 years, and 75% of the patients were girls. A total of 577 (9.7%) patients had at least 1 ED visit in the 6-month postoperative period, whereas 92 (1.6%) had 2 ED visits and 19 (0.3%) had 3 or more ED visits. The median time to ED visits was 33 days after surgery. Independent risk factors for ED visits were: older age, and greater levels fused (P<0.05). The top 5 most common reasons for ED visits were: pain/back or musculoskeletal, constipation/GI issues, asthma/ respiratory issues, upper respiratory infection, and dehydration. Rates of ED visits were similar among the US geographic regions. Patients who had an ED visit had significantly higher total 6-month health care payments than those who did not (P<0.001).

Conclusions:

Approximately 10% of the patients had ≥1 ED visit in the 6-month period after PSF for AIS. A majority of the diagnoses at these ED visits were outpatient medical issues.

Level of Evidence:

Level III.
Vascular Endothelial Growth Factor Protects CD200-Rich and CD34-Positive Hair Follicle Stem Cells Against Androgen-Induced Apoptosis Through the Phosphoinositide 3-Kinase/Akt Pathway in Patients With Androgenic Alopecia
Authors: Zhang Xuesong , Zhou Dongmei , Ma Tengfei , Liu Qingquan
Published: September 2019

BACKGROUND

5α-DHT can decrease the cell viability of the hair follicle stem cells (HFSCs) with CD34-positive and CD200-rich in bald scalp area of androgenic alopecia (AGA) patients and the apoptosis of HFSCs may be involved in the pathogenesis of AGA. The expression of Vascular endothelial growth factor (VEGF) turns to be weakened or disappeared in hair follicles of AGA patients.

OBJECTIVE

To investigate whether VEGF is involved in the apoptosis of HFSCs induced by 5α-DHT in the patients of AGA.

METHODS

By 5α-DHT, apoptosis of CD200-rich and CD34-positive HFSCs was induced and apoptotic rates up to 24 hours were assessed using flow cytometry. The expression grades of Bcl-2, Akt, caspase-3 and Bax were observed through Western blot analysis.

RESULTS

Vascular endothelial growth factor could cut 5α-DHT induced apoptosis down substantially in a concentration-dependent manner. The 5α-DHT induced decline in the rise of Bcl-2/Bax proportion and the increase in caspase-3 degrees were mostly reversed by using VEGF and the VEGF's anti-apoptotic actions were impeded through preventing the activation of phosphoinositide 3-kinase (PI3K)/Akt.

CONCLUSION

Vascular endothelial growth factor can protect CD200-rich and CD34-positive HFSCs from androgen induced apoptosis by means of the PI3K/Akt pathway.