bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Level of Use of Motivational Factors in SMEs According to Selected Criteria
Authors: Kmecová Iveta , Tlustý Michal
Published: January 2021

The research presented in this contribution is an analysis of the level of use of motivational factors in small and medium-sized enterprises (SME) in terms of three criteria, as selected by the authors. The primary goal was to draw conclusions on the basis of the formulated hypotheses concerning the degree of use of motivational factors by SMEs. The literature review outlines the issue of work motivation and motivational factors. The practical part of the contribution presents the course of the specific calculations and the evaluation of the hypotheses. The primary data were obtained using the SAAPM questionnaire, which was created as part of a project by the Slovak Academic Association for Personnel Management (SAAPM). The data are evaluated using the one-sample t-test statistical method. The research sample consists of a total of 610 small and medium-sized enterprises (SMEs) in the Czech Republic.
Assessment of Conflict Resolution Training at University
Authors: Sivrikova Nadezhda , Ptashko Tatyana , Chernikova Elena , Perebeynos Artem , Kharlanov Vitaly
Published: January 2021

The growth of conflicts in a changing world makes conflict resolution competence an important component of entrepreneurial competencies. Higher education should empower students to effectively prevent and resolve conflicts. The problem of assessing the educational process in the field of conflict resolution training and the result of this training is discussed in this article. The authors cite the results of an empirical study, the purpose of which was to determine the needs of students of the State University (Chelyabinsk, Russia) with regards to conflict management preparation. The survey relied on an analysis of the self-assessment of students´ own skills and commitment to the principles of tolerance, an assessment of the educational process, and the need to increase their own conflict management competence. 152 students of the State University took part in the survey, of which 63 were male and 89 female. The Likert scale was used. The results of the study showed that students assess the level of their own conflict resolution competence as high, as do they the educational process at the university. The limitations of the study are discussed at the end of the article.
Qualitätssicherung in der Intensivmedizin: Peer Reviews und Qualitätsindikatoren
Authors: Kumpf Oliver , Nothacker Monika , Dubb Rolf , Kaltwasser Arnold , Brinkmann Alexander , Greim Clemens-A. , Wildenauer René
Published: January 2021

Für eine gute medizinische Behandlungsqualität ist ein zielorientiertes Qualitätsmanagement notwendig. Dadurch werden zentrale Aspekte des Behandlungsprozesses transparent, um Entwicklungspotenziale zu identifizieren und durch externe Qualitätssicherung vergleichbar zu sein. Dieser Beitrag stellt die hierfür wesentlichen Verfahren vor – mit dem Fokus auf Verfahren der formativen Evaluation (Peer Review) und prozessbasierten Qualitätsindikatoren.
Study of Hearing Impairment in School-Going Children of Ghaziabad
Authors: Gaur Sushil , Arora Udita , Singh Vandana
Published: January 2021

Introduction Hearing is one of the traditional five senses that is also the fastest sense. Inadequate hearing acuity especially during early age has serious effects on the development of a child’s personality. According to World Health Organization, around 466 million people worldwide have disabling hearing loss and of these ~34 million are children. Hearing loss in children may occur due to several reasons, but ~60% of childhood hearing loss occurs from preventable causes. An early detection of these conditions plays an important role in reduction in magnitude of this problem.

Aims and Objectives The motive of this study is to estimate the prevalence of hearing impairment among school-going children in Ghaziabad on the basis of otological findings and tuning fork tests.

Materials and Methods A random sample of 500 school-going children between the ages of 6 to 14 years was selected from children attending ENT OPD in Santosh Hospital, Ghaziabad, over a period of 8 months from July 2019 till February 2020.

Results and Conclusion Prevalence rate encountered in this study was 13%, with unilateral hearing loss being more common than bilateral. The commonest cause was found to be cerumen. A higher prevalence was found in children from semiurban and low socioeconomic background. Since the commonest cause is preventable and readily correctable by proper management, early detection can reduce the burden of this disability.
Socioeconomic Burden of Type 2 Diabetes with Complications on Families: A Hospital-Based Study in Puducherry
Authors: Chinnusamy Manokaran , Janakiraman Sathiyanarayanan , Elayidath Roshna , Arvind Ram , Surendran Pravin
Published: January 2021

Introduction India is on the verge of diabetes mellitus (DM) epidemic. Within the near future, DM will put a big burden on India’s already vulnerable and resourced health care system. The objectives of the study were to (1) estimate DM treatment-related out-of-pocket expenditure (OOPE) among type 2 DM patients with complications from a tertiary care hospital and (2) estimate the economic burden on the household income of these patients due to DM treatment-related OOPE.

 

Methods A hospital-based cross-sectional study was conducted among known type 2 diabetic individuals with complications admitted in a tertiary care hospital. Using a structured pretested questionnaire required data, such as sociodemographic details, direct costs, and indirect costs in health care of DM, which were collected by a personal interview method.

Results Males constituted around 57% of the 100 patients who participated in the study. The average age of the population was 56 ± 10.03 years. The mean monthly income of family (in Indian Rupees [INR]) was 10,375.00 ± 9,201.55. Total expenditure includes the cost of medication, investigation, consultation fee, transportation, and miscellaneous expenditure. The average monthly OOPE in the management of DM for government and private facilities was INR 74 and 1,540, respectively. Among the total cost, the highest share was accrued toward medicines followed by diagnostics, miscellaneous, and transportation. There were 22% of families incurring catastrophic expenditure at the highest threshold of 40%. Socioeconomic status, history of at least one hospitalization in the past 6 months, and type of medications were factors found to be associated with costs.

Conclusion Heavy economic burden highlights the urgent need for the health care agencies and policy bodies to plan and prioritize local health policies and DM management schemes accordingly.
New aspects on the performance of a fundamental mode orthogonal fluxgate magnetometer based on amorphous wire cores
Authors: Tibu M. , Corodeanu S. , Hlenschi C. , Chiriac H. , Lupu N.
Published: January 2021

The performance of a fundamental mode orthogonal fluxgate magnetometer based on Co68.15Fe4.35Si12.5B15 amorphous wires produced at National Inst. of R. & D. for Technical Physics Iasi is presented. Our efforts are concentrated on reducing the sensor noise (magnetic noise + noise of the electronics) and at the same time on increasing the sensitivity in order to achieve a maximum signal to noise ratio. Making a parallel between conventional orthogonal fluxgate and fundamental mode orthogonal fluxgate operating principle, the differences in responsivity and noise have been explained based on magnetization mechanisms involved in the core.
Micromagnetic modelling of stripe domains in thin films with a columnar microstructure
Authors: Dengina E. Yu. , Bolyachkin A. S. , Kulesh N. A. , Vas’kovskiy V. O.
Published: January 2021

A micromagnetic model of thin films with columnar microstructure in the form of a matrix with reduced magnetic properties and embedded columns with high aspect ratio is presented. Such microstructure is typical for some films based on rare-earth and 3d transition metal alloys, in particular for La-Co films, that were chosen as an object for our modelling. Described structural features promote an effective perpendicular magnetic anisotropy that for thick enough films leads to formation of the stripe domain pattern. Our work addresses to the problem of finding equilibrium characteristics of stripe domains for the case of infinite columnar films. Herein it is shown how width of stripe domains, remanent magnetization and energies depend on number of replicas of periodic boundary conditions and the size of modelling volume. Equilibrium values of listed quantities can be found by extrapolating obtained dependencies.
Genome-wide mining of wheat B-BOX zinc finger (BBX) gene family provides new insights into light stress responses
Authors: Chen Shuhui , Jiang Wenqiang , Yin Junliang , Wang Shuping , Fang Zhengwu , Ma Dongfang , Gao Derong
Published: January 2021

The B-BOX (BBX) proteins are an important class of zinc-finger transcription factors involved in the regulation of plant growth and development, and have been identified in many plant species. However, there is no systematic study of common wheat (Triticum aestivum L.) BBX genes. Through comprehensive bioinformatics analysis, we identified and characterised 96 BBX genes from wheat, and provided the genes with a unified nomenclature. We describe the chromosomal location, gene structure, conserved domains, phylogenetic relationships and promoter cis-elements of TaBBX family members. The expression patterns under different conditions, especially under different hormones and light–dark conditions, were studied in detail. According to the diversity of conserved domains, we divided TaBBX proteins into five subfamilies. Gene-duplication analysis showed that duplication of chromosome segments was the main reason for the expansion of the TaBBX gene family. Detecting the expression profiles of six TaBBX genes in different tissues by quantitative real-time PCR, we found that the six genes are regulated under light–dark treatment, and that some TaBBX genes (TaBBX2.11, TaBBX2.13, TaBBX2.15 and TaBBX3.10) are strongly induced by the plant hormones abscisic acid, indole-3-acetic acid and salicylic acid. Our analysis of wheat BBX genes at the genomic level will provide a solid foundation for further identifying the functions of specific genes in light stress responses.
Investigation of performance measures of power generating unit of sewage treatment plant
Authors: Saini Monika , Goyal Drishty , Kumar Ashish , Sinwar Deepak
Published: January 2021

The main objective of present study to investigate the availability and profit of power generation systems established in sewage treatment plants. The sewage treatment plant is an industry in which waste sewage water has been treated and waste is used to generate power. For this purpose, a mathematical model has been proposed by considering constant failure and repair rates. The power generating unit in sewage treatment plant comprises six subsystems as sludge digester, gas holding tank, gas burner, gas scrubber, gas engine and power generation. By using appropriate redundancy technique in model development Chapman-Kolmogorov differential equations has been drawn with the help of the Markov birth death process. Availability and profit have been analysed based on making variation in the failure and repair rates. The numerical and graphical results have been depicted for a particular case. The derived results have been discussed with system designers and found useful.
A Novel Model for Building Digital Infrastructure for Biodiversity Studies
Authors: Dhindsa A , Bhatia S , Agrawal S , Sohi B S
Published: January 2021

In this research work, a novel proposal has been given to build a digital infrastructure for conducting Biodiversity studies. The proposed system allows citizens and professionals to come together and work on a common platform. This system supports different types of data such as protein, gene, video, image, text, and sound which enables it to support all kinds of instrumentation. Also, this system can be used for connecting telescopes, probes, sensors, cameras, and microscopes with the cloud and data can be stored in real time. The system allows the use of international standards such as Global Biodiversity Information Facility (GBIF) for building biodiversity data. It is a collaborative system where discussion on identification and validation of the organisms can be done through seamless integration with third party applications.
A HYBRID APPROACH FOR CROP YIELD PREDICTION USING MACHINE LEARNING AND DEEP LEARNING ALGORITHMS
Authors: Agarwal Sonal , Tarar Sandhya
Published: January 2021

Agriculture is defined as the science and art of cultivating the flora and fauna. Farming in India is ranked as second around the globe and occupies 60.45% of Indian land. The Indian economy, dominatingly, depends upon farming along with agro-industry things. The soil ingredients (like Nitrogen, Phosphorous, Potassium), crop rotation, soil clamminess, atmospheric and surface temperature, precipitation, etc, play an efficient role in cultivation. The present evidence related to this field includes a model which is incorporated with ML algorithms (Random Forest, Decision Tree, Artificial Neural Network) to determine best crop. In this paper, the proposed model is enhanced by applying deep learning techniques and along with the prediction of crop, a clear information is achieved regarding the amounts of soil ingredients needed with their expenses separately. It provides a better accuracy than the existing model. It analyzes the given data and help the farmers in predicting a crop which in return help in gaining profits. The climatic and soil conditions of land are taken into consideration to predict a proper yield. The objective is to present a python based system that uses strategies smartly to anticipate the most productive reap in given conditions with less expenses. In this paper, SVM is executed as Machine Learning algorithm while LSTM and RNN are used as Deep Learning algorithms.
Different Materials, Structures and Parameters for Organic Thin Film Transistors
Authors: Gupta S , Mittal P , Juneja P
Published: January 2021

This paper assesses the topical progressions in the province of organic electronics especially the ones having SM and are made of polymer materials. It shows the analysis of structural disparity between top contact and bottom contact Organic Thin Film Transistors, thus rendering clarity to the conduction mechanism and performance governing parameters. Furthermore, an insight to a variety of materials that can be deployed in making different layers of an OTFT has been presented. In addition to this the parameters that oversee the performance of the device have also been highlighted. An elucidation of a variety of applications, limitations and scope has been reflected in the paper as well.
Predictive programmatic re-targeting to improve website conversion rates
Authors: Prasad Abhiram , Chokshi Sneha , Khan Sahil
Published: January 2021

In the era of programmatic advertising, the advertisers have huge amount of first party data to leverage on enabling them to do highly granular re-targeting. Programmatic re-targeting is the ability to use data to show an ad to a user who has demonstrated an interest in your product offerings before. Re-targeting ads are a powerful conversion optimization tool and are typically known to outperform conventional targeting in terms of performance. As per 99 Firms, 41% of marketing allocation in 2018 to paid display spend was on re targeting and for most of the websites, only 2% of web-traffic converts on the first time visit. In this paper, a conversion is referred as a purchase made and a converting user is one who made the purchase on the website. The question that arises is - “should we be re-targeting all the users who have landed on the site?”. In ad campaigns which has low budgets or in campaigns where the conversion rate is really low even though a huge volume of users visit the site, it may not make complete sense to simply re-target all those users, instead we would want to re-target those who are clearly showing an intent to make a purchase either through their on-site browsing behaviors or their past conversion patterns. Through this paper we present the use of first party privacy preserving data to do predictive programmatic re-targeting of users who are going to make a conversion in the next few days given their past site-browsing and conversion behavior using a structured data science and advanced ML based framework. Additionally, this project allows to tie the model results to real time programmatic activation by the creation of user segments depending on whether the user is going to make a conversion for the first time, or is converting again. The final outputs are these user segments, which are going to be used by in house ad-traders who would be able to bid deferentially for a specified period of time against each of the segments on a demand side platform. We have successfully tested this model on 2 advertising clients and were able to capture 80-85% of the actual converts happening over the next few days of them landing.
Experimental studies on R.C. columns with natural fibers
Authors: Suthar A R , Patel Y S
Published: January 2021

Adding natural fibers to concrete is a modern technique in construction industry. The aim of conducting the research is to compare the load carrying capacity of Reinforced Cement Concrete (RCC) columns by adding natural fibers in it. Total 30 columns were casted for observing the compressive strength of the column. Natural fibers like Rice husk, wheat husk, coconut fiber and wood fiber were added in 1 % and 3 % by weight of cement. On varying the percentage of replacement from 1% to 3%, rice husk was having the most positive impact on loading capacity as its load carrying capacity raises 1.67 times of normal column. On considering the all tests performed, rice husk fiber was found to be the best in replacement in concrete. The strength of the Fiber Reinforced columns (FRC) varies from 0.76 to 1.67 times in comparison to plain column. Adding fibers to the concrete raised the strength of column in the range of 1.5 to 3 times of design load. Coconut fiber columns showed poor ductility as compared to the other natural fibers i.e. wheat husk, rice husk and wood fiber. The coconut fiber column showed debonding between fibers and concrete at the time of ultimate loading. Failure of FRC column was nearly same as plain column. Hence natural fiber concrete is one of the environment friendly and economic option, which is used to construct low rise building
Crystal Structure Visualization of Niobium Nitride (NbN) Thin Film
Authors: Prabhakar B. , Wani T.A.
Published: January 2021

The well-known program for the visualization and exploration of crystal structural has been by using diamond software. The diffraction technique is used for study the Niobium Thin Film (NbN) and good quality, good resolution powder patterns are recorded in these research work. The calculation of angles by measuring the distance between two atoms, crystal structure visualization and the thin film (NbN) diffraction pattern is main focus in this research work.
Correctness of determination of energetic materials high temperature decomposition kinetics
Authors: Zarko V E
Published: January 2021

The kinetic parameters of high temperature decomposition kinetics are widely used in evaluating the characteristics of thermal explosion, ignition and combustion of energetic materials. At present, the true and correct data on the high temperature kinetics of energetic materials condensed phase reactions are unknown and probably will remain unattainable in the nearest future. This is because of enormous technical difficulties to obtain such information and the absence of proper theoretical approaches for treatment of non-isothermal data. Evidently, with highly exothermic reactions it is impossible to conduct experiments at elevated temperatures using approaches of a low heating rate or isothermal ones. The improvement of characteristics of existing devices for thermal analysis is impeded by both technical complications and difficulties of performing experiments with ultrathin specimens of energetic material to ensure the conditions of uniform heat-up of the bulk of the substance. Based on the results of numerical simulation it is shown in this paper that the approach suggested 50 years ago by A. G. Merzhanov of using ignition delay data for deriving high temperature kinetics was not theoretically justified and can provide only very approximate values for such kinetics. The paper concludes on the today’s relevance of the tasks on elaboration of mathematically justified techniques for determining kinetic parameters of global exothermic condensed-phase reaction, which will be based on the experiments on EMs ignition.
Investigation of CL-20/TFAZ cocrystal: preparation, structure and performance
Authors: Liu N , Duan B H , Lu X M , Wang B Z
Published: January 2021

The cocrystals of hexanitrohexaazaisowurtzitane (CL-20) and 7H-trifurazano[3,4-b:3’,4’-f:3”,4”-d]azepine (TFAZ) in a 1 : 1 molar ratio were prepared by both slow evaporation and self-assembly method. Structure determination showed that it belongs to the monoclinic system (space group P21) with crystal density of 1.932 g cm−3. The intermolecular hydrogen bonds and N–O•••NO2 type interactions are demonstrated as the predominant driving force in cocrystal formation. Furthermore, the cocrystals were successfully synthesized by a self-assembly method using only water as solvent at mild conditions, and the product yield was up to 92.3%. The two types of cocrystals were fully characterized by powder X-ray diffraction and scanning electron microscope. Moreover, the thermal behavior, sensitivity, and calculated detonation performances of the cocrystal were evaluated. The cocrystal exhibits good thermal stability (Td = 242.8 °C), low impact sensitivity (H50 = 42 cm) and friction sensitivity (Pf = 38%), high crystal density, and high calculated detonation velocity (9103 m/s). This work opens up a new perspective in the environment-friendly preparation of energetic cocrystals on a large-scale, as well as provides a potential low-sensitivity and high-energy explosive.
Effect of hydroborate iron additives (BH-Fe) on the properties of composite solid rocket propellants
Authors: Pang W Q , DeLuca Luigi T. , Wang K , Xu H X , Xiao L Q , Fan X Zh , Li H
Published: January 2021

Several industrial - and research - types of hydroxy-terminated polybutadiene (HTPB) - based composite solid propellants with and without hydroborate iron additives (BH-Fe) were experimentally prepared. In general, they feature the same nominal composition, but different mass fraction of BH-Fe particles are investigated as burning catalysts and contrasted to a conventional formulation without BH-Fe particles, which are taken as reference. Strand burning rates and the associated combustion flame structures of propellants were analyzed. The mechanical sensitivity and microstructure surface of the formulations were compared to that of a referenced propellant already certified as steady. The results show that the BH-Fe powders are of irregular shapes, which tend to disperse or not stick together easily into cold clots. The BH-Fe powder are insensitive for friction and impact stimuli (0%, >125.0 cm) and all the propellant formulations containing different mass fraction of BH-Fe particles were sensitive to impact and friction (96 %, 10.0 cm), which is a bit sensitive to the referenced formulation without BH-Fe particles (92 %, 30.2 cm). The hydroborate iron additives (BH-Fe) can affect the combustion behavior and change the burning rate effectively. The burning rate can be increased more than 12.1 % for 3 % of BH-Fe particles replaced common Al powder in the formulations. The burning rate and pressure exponent values depend little on the formulation of the mass fraction of BH-Fe powder. A change of part mass fraction of BH-Fe particles may boost the burning rate a bit higher than that of the common Al powder, and the pressure exponent was increased little from 0.30 to 0.31 at the experimental pressure range.
Research on Wave Effect of Hypervelocity-KE Rod to the Earth
Authors: Wang P , Zhang M , Qu H Y , Hou B J , Liu X C
Published: January 2021

The goal of this paper is to present a test method used to characterize the damage effect of the hypervelocity-KE rod to the earth. Firstly, according to the numerical simulation results, the damage effect and their characterization parameters is carried out when the hypervelocity-KE rod impacts the Earth. And then the test methods for these characterization parameters are brought forward one by one in theory. Finally, by the test methods, the data from the damage effect of the 100kg hypervelocity-KE rod to the Earth are achieved. The content in this paper would benefit for the research on the KE weapon.
Roll forming of projectile body with curved rotary profile
Authors: Zhang B H , Hu B , Wei C Y , Zhao X , Zhang Z M
Published: January 2021

In this paper, a novel roll forming (RF) process is introduced. A kind of 120-mm projectile body with curved rotary profile is formed by the RF process. The RF process is compared with the traditional process of machine using the billet of draw. Based on the results, it can be concluded that the weight of billet reduces 28% by the presented process comparing with the traditional process and the reducing amount will increase with the increasing of the length of curved rotary profile. The presented process can use traditional draw press and has the same forming productivity. It also has the merits of lower forming force and machine time. The die of the present process is more complex and the manufacturing cost is higher than that of the traditional draw, but the die life of the present process is higher.
Research on development status and technology trend of intelligent autonomous ammunition
Authors: Liu D W , Sun J , Huang D G , Wang X Y , Cheng K , Yang W Q , Ding J Y
Published: January 2021

Research on the new tasks and capabilities are required for ammunition in the future intelligent air combat, the concept of smart munitions is put forward, and the intelligent development approaches of single equipment intelligence, system intelligence, swarm intelligence and system of system intelligence are put forward. This paper classifies and analyzes the relevant projects currently carried out by the US military, and on this basis summarizes the development trend of airborne smart munitions. Finally, some suggestions for the development of airborne smart munitions in China are given. The above research results will provide reference for the construction of intelligent equipment system of airborne intelligent ammunition and the direction of technology research.
Research on machining technology of complex structure parts of high-speed train body
Authors: Chen H H , Meng F J , Zhang D S , Miao L Q , Qiao H , Sang M , Qian D M , Wang W B
Published: January 2021

According to the high-speed train body chassis connecting plate and the side wall key piece structure is complex, the processing difficulty is big, the processing is easy to deform, the precision is not easy to control, the processing efficiency is low, carries on the processing craft characteristic analysis, produces the processing craft analysis report. The dynamic milling forces in X, Y and Z directions during milling process are tested by means of testing and analyzing the dynamic characteristics of the machine tool, and the dynamic performance of the system can be tested by means of modal test, the transfer function of the system is obtained, and the modal parameters such as natural frequency, damping ratio and modal stiffness are obtained by mode fitting on the basis of the transfer function data, complete the dynamic characteristic analysis of the machine tool. Based on the modal analysis of the whole process system and the dynamic model analysis of the milling process, the chatter stability region of the milling process is simulated by using the theory of regenerative chatter, the results of chatter stability region related to milling process parameters are given.
Composites in extreme environments: Effects of high strain rate, humidity and temperature
Authors: Quino G , Pellegrino A , Petrinic N
Published: January 2021

Multifunctionality, lightweight and resistance to corrosion are some of the several advantages that fibre composites display with respect to other materials across a wide range of applications. In aerospace and marine industry, however, we can encounter challenges arising from certain working conditions that can significantly affect the mechanical response and integrity of composite structures. First, humidity or water exposure can induce reduction of the material strength and stiffness. Second, hot or cold temperatures that change the level of ductility in the composite. Finally, dynamics loads that may appear during service require strain rate sensitive properties to be considered. In this work, we show experimental capabilities and methodologies developed to account for all those three effects: rapidly applied loads (impact), humidity and temperatures from -55°C to 93°C. This understanding sets the basis for the development of advanced models to design better structures.
Modelling the movement of slurry in the channel of a nature-like pump used for the safety laying of the worked out space
Authors: Vasilyeva M A , Yusupov G A , Nagornov D O , Puskarev A E , Andreev M N , Kuskildin R B , Serzhan S L , Kuskova Ya V
Published: January 2021

The most important task of the production of the mineral raw materials industry is to increase the efficiency of the equipment and infrastructure in operation. In particular, this also applies to the need to create transport systems with high productivity while reducing the cost of transporting mineral raw materials and waste from its processing. Particular attention is paid to the use of hydraulic filling systems as a measure to prevent man-made tectonic earthquakes during prolonged and continuous development of deposits. In this paper, we consider the problem aimed at solving the fundamental problems of developing effective methods for controlling the flow of pasty substances in pipelines of variable cross-section, intended for the production of pumping equipment and used in such industries as mining, chemical, food, etc.
Research and application of SVM analysis model for spectral fingerprint of mixed gas
Authors: MuRong Zh , Guo J Sh , Zhang Y X , Jiang Y , Yu Zh G , Bai P
Published: January 2021

The infrared spectrum analysis method has the characteristics of non-contact, high-speed and no consumption of sample, There is some useless interference information that is not sensitive to the analysis results in the infrared spectrum data sample. Combining support vector machine with infrared spectrum analysis, the band of spectrum data that is sensitive to gas concentration is selected by experiment. The useless, insensitive and disturbing information is removed, and the useful information is retained. And then the infrared spectrum analysis model based on support vector machine is used to complete the output of gas concentration of mixed gas components. Based on Lambert’s theorem and using the known spectrum data samples as input in experiment, the sensitivity analysis of the mixed gas spectrum data samples is carried out by using the variable sliding window technology which is similar to the center wavelength and band-pass filter, and the start point and band width of the band are both variable. The band with small error is selected as the spectrum data fingerprint series to edit and splice, and then the mixed gas data sample with the fingerprint characteristics of the mixed gas component gas spectrum data is formed. On this basis, a support vector machine based infrared spectrum analysis model of mixed gases is established. The analytical model includes two processes: training and verification. The preconfigured mixed gas samples that are known concentration is fingerprint edited and processed after scanning by the spectrometer. Then the gas samples are formed the spectral data samples which can be considered as the input samples of the analytical model. The model is trained to determine the support vector and corresponding weight of the analytical model based on the spectral data samples; The fingerprint characteristic data samples of the unknown-concentration mixed gas spectrum are tested by the analytical model that has determined parameters. Then, the gas concentration of the mixed gas components is obtained. The aspects of spectral data’s fingerprint feature extraction and the selection of the model’s main parameters are researched, through experiment, the methods and processes of fingerprint feature editing and splicing extraction of spectral data are studied, and the influence of the model’s parameters on the analysis results is optimized. The experimental results show that under the condition of optimizing the model’s parameters, selecting the fingerprint features of the spectral data reasonably and constructing a new spectral data sample with the fingerprint features of the mixed gas component can help eliminate the measurement cross sensitivity caused by the cross overlap of the absorption spectra of the mixed gas component, and improve the calculation efficiency and the analysis accuracy, which has theoretical and practical value.
Method for accurate multi-target discrimination and compound friend or foe identification of millimetre wave system based on laser ranging technology
Authors: Zhang Lei
Published: January 2021

This paper uses laser ranging technology, by multiplexing of ranging buttons, reconstruction of laser rangefinders and other equipment, and utilizing distance-based comparison methods to achieve accurate discrimination of millimetre-wave identification friend or foe systems under multi-target conditions, further improving identification reliability. The experiment proves that the method is feasible and effective.
Random disturbance in cavity boundaries
Authors: Wang Kangjian , Rong Guang , Mu Qing , Yin Hongqiao
Published: January 2021

The water condition usually is complicated due to many uncertain factors such as internal wave, density differences and so on. So the real cavity boundaries is hard to predict for a supercavition projectile. In this work, a random disturbance model is established based on Poison process of random mathematics. This model is employed to the Logvinovich cavitation expansion equation for simulating a cavity in real ocean environment. A detail of cavity outline is obtained by this calculation. The results indicate that the cavitation boundary of higher velocity case is smoother than lowers. The parameter λ of Poison model is a key factor of disturbance frequency, which largely affects the length of cavity. The λ is proportion to the cavity length. This provides a new method for water environment cavity analysis.
Multi-hypothesis distributed video compression sensing based on key frame secondary reconstruction
Authors: Yuchen Yue , Jianhua Luo , Hua Li
Published: January 2021

Reconstruction algorithms are the key technology of distributed video compressed sensing. The research focus of traditional distributed video compressed sensing reconstruction algorithms is mostly on improving the reconstruction quality of non-key frames, ignoring the reconstruction quality of key frames, and the information of key frames are not Underutilized. In view of the above problems, a distributed video compression sensing algorithm based on secondary reconstruction of key frames is proposed. Firstly, the fractional order total variation algorithm is used for the initial reconstruction of the key frame, and the reconstructed frame is used as the reference frame to assist the secondary reconstruction of the key frame, which improves the reconstruction quality and reduces the calculation complexity. Then, a multi-reference frame bidirectional prediction hypothesis set optimization algorithm is proposed to increase the number of reference frames and improve the quality of the hypothesis set through optimization without expanding the size of the hypothesis set. Experimental results show that the overall performance of the proposed algorithm is better than the most advanced methods.
A three-dimensional non-hydrostatic mathematical model with mixed triangle and quadrilateral grids
Authors: Yu G N , Lv B , Xing Y
Published: January 2021

The three-dimensional numerical models based on the hydrostatic pressure hypothesis can’t accurately and effectively simulate the cases of estuaries or natural rivers with the presence of short wave flow, stratified gravity flow, sudden change of local topography or flow near underwater buildings. Therefore it is useful to resort to a more accurate model in which the hydrostatic assumption is removed. Based on the mixed grids of triangle and quadrilateral, a three-dimensional non hydrostatic mathematical model is presented. The control equations are discretized by the semi-implicit fractional step method. The pressure is divided into the hydrostatic pressure and non-hydrostatic pressure terms. At each step, the water level is calculated by solving the sparse equations, and then the non-hydrostatic pressure is obtained by the pressure Poisson equation. Three typical examples were adopted to simulate strong three-dimensional flow. As a result, the results show that the model can accurately and effectively simulate strong three-dimensional flow with a few layers.
Research of the influence of the excavating and automotive equipment complexes parameters on the speed of faces advance
Authors: Kuznetsov D V , Kosolapov A I
Published: January 2021

The article presents the results of the research on the equipment complexes parameters impact assessment with electric and hydraulic excavators and dump trucks on deposits development intensity. The classification of deposits according to the relative difficulty of development is introduced. For the open pits of each of the identified five classes, the possible speed of faces advance is determined with the diversity of equipment parameters, deposits parameters and panel blocks.
Discussion on the Issues of Rotor-Stator Interference in Pump Turbine
Authors: Xu Hongquan , Gui Zhonghua , Li Tieyou , Liao Cuilin , Meng Long , Zhao Lice
Published: January 2021

There are serious vibration issues of powerhouse in some pumped storage power plants and it affects severely the safe and stable operation of power plant. In order to settle the issues which have troubled the hydropower technology for several decades, extensive researches have been made. The rotor-stationary interference between rotating runner and stationary guide vanes are one of the researched issues concerned most and has the biggest influences. In this paper, the different opinions are presented. Firstly, the characteristics of pressure variations before and after the guide vanes are discussed and it indicates that, the pressure distribution is not uniform due to the turbulent flow around guide vanes but there is no pressure fluctuation with the dominant frequency of rotational frequency multiplying guide vane number. The interference precondition of pressure waves is there are two pressure waves with the same frequency, thus the new opinion, there is no rotor-stationary interference in the vaneless area, is presented. Secondly, equations of rotor-stationary interference presented by Hiroshi Tanaka and its derivation process are introduced. The equation foundation, physical meanings of parameters and equation dimensions are analyzed, and it is concluded that it is wrong to combine the pressure waves from rotating part and stationary part by multiplying the two pressure waves. And also the following mistakes and unreasonable issues are described. The studied objects are not consistent with that in practical application, the pump condition is not considered, the steady operation is taken as unsteady, and the definition of nodes is mistaken. The correct combination method of rotor-stationary interaction are presented.
Effects of Impeller Trimming on Performance in a Double-suction Centrifugal Pump
Authors: Deng Qifan , Pei Ji , Wang Wenjie , Yuan Shouqi
Published: January 2021

In order to research the relationship between impeller trimming and performance in a double-suction centrifugal pump, impellers were trimmed 11mm and 22mm respectively. Numerical methods were applied combined with the original one, and experimental validation was also carried out on original and 11mm model. The performance and difference of total pressure between volute inlet and outlet was calculated, meanwhile, distributions of velocity and turbulence eddy dissipation on volute middle section were analyzed. The results indicate that the head drops with the trimming process and discontinuity appears when trimmed 22mm. The impeller trimmed 11mm is the most efficient under part-load and design conditions, while the original model has the lowest efficiency. Efficiency in trimmed cases decreases dramatically under over-load condition, especially when trimmed 22mm. Duo to rotor-stator interaction between impeller and volute receded by the enlarged clearance, the head losses inside the volute decrease with impeller trimming but increase significantly under 1.4Qd when trimmed 22mm. The extremely high shock losses resulting from exaggerated impeller outlet flow angle and dissipation near volute tongue account for it. Moreover, the losses in volute diffuser channel increase due to the vortexes generated by flow separation and backflow. The losses in volute will be improved by impeller trimming within reasonable limits in a double-suction pump. This research provides theoretical foundation for impeller trimming in double-suction centrifugal pumps.
Optimization for First Stage of Multistage Pump Based on Response Surface Methodology
Authors: Jiang Wei , Pei Ji , Wang Wenjie , Yuan Shouqi
Published: January 2021

To improve the efficiency of a multistage centrifugal pump at design point, the response surface methodology was applied to construct an approximation function between the design-point efficiency of the first stage in multistage centrifugal pump and the design variables of the impeller. First, important geometric parameters are selected as factors of a one-factor experimental design. Four parameters that had greater influence on the hydraulic efficiency were screened out from the simulation results using parameter sensitivity analysis. The optimal design points for each level of the parameters were then determined by central composite design and the response surface analysis method. The efficiencies of the impeller schemes generated in the Design-Expert software was executed with CFD. The effects of the single parameters were analysed, and the approximation model solved to find the optimal parameter combination that improve the efficiency by 3.62% at design point. And the inner flow was improved in high flow rate condition.
Experience Measurement of Winter-Kennedy method on low head tubular turbine units
Authors: Zhou X Z , Wang Z W , Ahn S H , Xia M , Yi Z C
Published: January 2021

With large development of renewable energy, especially the low head hydraulic power stations, specifications of the turbines have been got more and more attentions. The discharge, which is one of the most important parameters relative to unit performances, is difficult to be determined according to the passage layout. In this paper, applying “Winter-Kennedy” measurement method though modification and comparison with test and simulation, characteristics and coefficients of turbine units, derived from different pressure at certain locations, are calibrated and established. After further verification, it will of great help to confirm the relationship of unit output, water head and hydraulic efficiency, as well as optimal dispatching and stable operation of hydropower stations.
Fatigue Life Prediction of a Pump Turbine Runner
Authors: He Q L , Liu T , Yang X L , Chen F N , Wang C , Liu J S , Wang Z W
Published: January 2021

The working environment of the runner of a hydro-turbine unit is complex, and it is subjected to relatively large and variable water pressure. Fatigue cracks may occur after a long period of work, and even cause the runner to lose its working ability. The fatigue crack problem of hydraulic turbines should be paid attention to. This paper introduces the nominal stress method which is often used to analyse the fatigue life of a hydraulic turbine unit. Modelling and numerical calculation are carried out for a pump turbine unit. Stress concentration points and load spectra are calculated for different working conditions of the turbine. The load spectra are processed by rain flow counting method. The fatigue life of the runner under different working conditions is carried out by Miner criterion. The results show that the fatigue life of the unit tends to be infinite under steady working conditions, and the fatigue life under variable working conditions is far less than that under steady working conditions. Therefore, from the point of view of fatigue life, the working process under variable working conditions should be minimized to improve the service life of the unit.
Research on Unsteady Characteristics of Pump Turbine in Pumping Mode
Authors: Liu Yong , Ran Hongjuan , Wang Dezhong
Published: January 2021

A study on the unsteady characteristics of pump turbine in pumping mode was made. Basing on the existing research, this paper is aimed at providing valuable reference for hydraulic design, structure optimization, fault diagnosis of pump turbine. CFX simulation verified by experiment was made to analyze the distribution law and propagation characteristic of pressure and its pulsation in the whole fluid field. Research shows that the pressure pulsation owns different propagation characteristic from the flow velocity pulsation. The pressure pulsation component with guide blade frequency has very special properties in stationary flow passages, while the pressure pulsation component with runner blade passing frequency is absolutely different. Blade constraints have significant effect on the unsteady properties of pressure and flow velocity. Besides, some other analysis was talked about, such as the external characteristics, pressure pulsation near the volute tongue, and so on.
Coupling Spatial Distribution and Industrial Structure Optimization Analysis of Economic and Environmental Pollution in Chongqing
Authors: Gou Xiaomeng , Li Yao
Published: January 2021

In recent years, as one of the old industrial bases in China, although it has been promoting the construction of new industrialization, Chongqing is still facing a more severe situation of industrial pollution. In order to further upgrade the optimization of industrial structure in Chongqing, the paper combined with 2773 cases of Chongqing pollution administrative penalties. Select industrial pollution enterprises administrative penalty amount of the 38 districts and counties in Chongqing as cross-sectional data, the spatial correlation of industrial pollution in Chongqing was analyzed by exploratory spatial analysis. Then, using the coupled coordination degree model, the evaluation index system of economic development and industrial pollution coupling degree in Chongqing area is established, and the spatial pattern of the economic environment coupling degree in Chongqing is analyzed. It is found that the spatial agglomeration characteristics of industrial pollution in Chongqing are not obvious, and the regional pollution is different, the economic environment system is in the state of low coupling, the spatial types of the coupling degree of regional economic environment are the most antagonistic economic environment, and the minority is the low coupling region. Based on the results of spatial layout, this paper analyzes the industrial structure of Chongqing City and put forward the optimization strategy of industrial structure.