bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on Parallel Operation Characteristics of High-pressure Pumps Applied in Coal Mine Hydraulics permeability improvement
Authors: Shen Kai , Xiong Wei , Ba Quanbin , Liao Yin , He Lipeng 
Published: September 2021

Abstract
Nowadays, plunger high-pressure water pumps applied in large-scale mine are mostly used in coal mine hydraulics to increase permeability, and it is difficult to transport objections underground. Besides, the permeability improvement is affected during overhaul too. Therefore, multiple small high-pressure water pumps operating in parallel can be used to solve the problems mentioned above instead of large high-pressure water pumps. Moreover, the operating principle of the plunger high-pressure pump determines the specific flow fluctuation characteristics during its operation, and similar flow fluctuations also exist during the operating of parallel pump sets. The transmission model and AMESim hydraulic simulation model of single, parallel plunger pumps are established, taking the BQW-22/50 high-pressure water pump as an example. The operating characteristics of a single plunger pump and a parallel pump group are analyzed in this paper. The results are obtained as follows: the instantaneous discharge flow curve of a single plunger pump conforms to a sine function; the flow of the parallel pump set is the superposition of the flow of multiple plunger pumps; the instantaneous discharge flow curve changes under the influence of the phase deviation angle between the pumps; when parallel pump sets are running, there is an optimal phase deflection angle between the pumps, which minimizes the flow fluctuation of the pump sets; when four high-pressure water pumps are operated in parallel, the optimal phase deflection angle between the pumps is π/12 or π/4.
Simulation of shock test for an AUV propulsion motor based on DDAM
Authors: Liu Lei , Zhao Zengwu , Wei Juan , Li Xiaobei , Yuan Liwei 
Published: September 2021

Abstract
The paper studies the simulation of shock test for a propulsion motor equipped on an AUV. According to DDAM, the modal parameters are calculated using finite element analysis. Then the input spectrum of impacting acceleration is given based on modal analysis. The response after shocking is analyzed at last. Distribution of the stress in different directions are given, showing that the shock resistance performance of the propulsion motor satisfied the shock test.
Research on Human-Machine Interface Design of Smart Refrigerator Based on Conjoint Analysis
Authors: Yang Jing , OuYang Wumin , Chen Yuqi 
Published: September 2021

Abstract
The purpose is to study the design method of the smart refrigerator man-machine interface. The method adopts conjoint analysis, starting from the human-machine interface of the smart refrigerator, and splitting and orthogonally reorganizing the main components and element types of the interface, allowing users to score the virtual experiment scheme and statistical data, and calculate the utility value of each element and type, analyzes the user preference in the smart refrigerator man-machine interface, and then draws the design principles of the smart refrigerator man-machine interface, and generates the final interface design plan. This paper concluded that through the conjoint analysis method, multi-factor data could be statistically analyzed. Therefore, enable designers to better understand the user preference for the smart refrigerator man-machine interface, improve user experience and user viscosity, and providing ideas for similar interface design in the future.
Research on Calibrating Device of Daily Clock Time Difference Testers Based on DDS Cascade Technology
Authors: Yan Ming , Zhang Shengnan , Yin Fucheng , Yang Ming , Li Nuo 
Published: September 2021

Abstract
According to the specific requirements in the national verification regulations of JJG488-2018 “Instantaneous Daily Clock Time Difference Testers”, this paper has developed a calibration device for an instantaneous daily rate measuring instrument. Under the premise of not using FPGA, CPLD, DSP and complex algorithms, the device adopts DDS chip cascade technology and energy conversion principle to ensure that the maximum allowable error of the daily difference is 0.001s/d. Therefore, the device is not only suitable for personnel in the field of measurement to calibrate instantaneous daily clock time difference testers, but also can be used as a general-purpose measuring instrument with frequency measurement functions such as high-resolution frequency synthesizer calibration frequency meters.
Research and design of a multifunctional intelligent walking stick
Authors: Chen Yan , Meng Chaoying , Li Yunlong , Sun Taokai , Wang Shangyu 
Published: September 2021

Abstract
This paper designed a multifunctional intelligent walking stick for the elderly. The mechanical structure of the walking stick is provided with a hook, auxiliary mechanism for standing up, an anti-tripping mechanism, a small table board and telescopic adjustment. The auxiliary mechanism for standing up can make it easier for the user to stand up. The anti-tripping mechanism makes it safer for the elderly to walk without tripping. The retractable adjustment can meet the needs of people with different heights. The walking stick is also equipped with intelligent elements, such as lighting lamp, automatic time alarm, fall alarm system, manual alarm system, GPS positioning and MP3 music functions. When the elderly feels unwell, they can press the alarm switch, and the alarm bell will turn on, which can attract passers-by and improve the chance of rescue. When the fall alarm system is turned on, if the user falls, the alarm bell will ring, At the same time, the GPS positioning module will send the crutch position to the intelligent terminal to remind the guardian in time. Compared with the traditional crutches, the crutch has many functions and it is more convenient to use and safer.
PID Parameter Tuning for Buck Controllers Based on an Improved Differential Evolution Algorithm
Authors: Zhao YJ , Qiu QX , Zhao X 
Published: September 2021

Abstract
With the wide application of Buck converters, it is of great significance to select the optimal PID controller parameters to ensure the dynamic and steady-state performance of the Buck converters. On this basis, a PID parameter tuning method based on an improved differential evolution algorithm is proposed. Also, a crossover approach with population generation across orders of magnitude, elastic boundary absorption, and retention of some combined features is put forward. In addition, an adaptive mutation factor, and a cost function that suppresses overshoot and is sensitive to the tuning time are designed. The results of 10 tests show that the differential evolution algorithm fails in the case of parameters in a range cross orders of magnitude, while the algorithm proposed in this paper enables a better combination of PID parameters selected in terms of speed and stability, with a wide search space and stable convergence results.
New type solar energy micro-polluted water purification technology and device
Authors: Huang Yaqin , Rong Lishan , Yu Feng , Chen Ziqian , Shi Ling , Wang Xinyue , Gong Wei 
Published: September 2021

Abstract
The “new micro-polluted water purification device” is mainly used to deal with the micro-pollution of some water bodies. The purpose is to purify micro-polluted water through this device to provide necessary domestic water for human life. This project designed a simple, economical and environmentally friendly sewage treatment system in order to solve the water problem in water-scarce regions such as Africa. By simulating the process of natural water cycle, using solar energy as the power source, the micro-polluted water is purified into potable water. And store it in a water tank. The device flexibly utilizes clean energy such as heat energy and wind energy to meet the demand for water extraction in different situations. The device realizes the purification treatment of micro-polluted water body under the condition of low cost and low energy consumption.
Research on the influence of bottom expanding and filling on bolt sliding instability and supporting effect
Authors: Wang Jinrui , Nan Hua , Wang Shuai 
Published: September 2021

Abstract
Aiming at the problems of soft coal roadway, such as low hardness, fracture development, poor bonding ability between anchoring agent and surrounding rock of borehole, weak shear resistance, which easily lead to resin bolt sliding instability in coal roadway. To effectively support soft coal roadway, the method of bottom expanding and filling is adopted. This method expands the hole at the bottom of the borehole and replaces the soft coal with high-strength material to achieve the same position modification of the soft coal body at the bottom of the borehole and improve the anchoring performance of bolt support. Through laboratory tests and numerical simulations, the sliding instability of the bottom reamed bolt is evaluated. the results show that, with the increase of the reaming times, the anchoring force changes in direct proportion to the reaming times, except single of the reaming times, the anchoring force increases fast under quintuple of the reaming times, and increases slowly over quintuple of the reaming times, so it is considered that quintuple reaming is the most appropriate.
Energy Saving Application of Variable Speed Auxiliary Pump Plus Hydro Turbine in Circulating Cooling Water System
Authors: Wang Peng , Luo Xingqi , Chen Senlin , Cai Qingsen , Lu Jinling 
Published: September 2021

Abstract
The circulating cooling water system (CCWS) is a common industrial auxiliary system, and water pumps need to consume much energy to transport cooling water to distributed heat exchangers. Previous studies show that a pump network configuration with constant speed auxiliary pump plus hydro turbine (CSAP-T) plays a significant role in energy conservation. However, given the fluctuations in the production load and cooling water supply temperature, the flow demand of heat exchangers for cooling water varies. Under different working conditions, the CSAP-T scheme cannot supply the minimum cooling water flow required by all heat exchangers at the same time, thereby wasting energy. Therefore, this paper proposes a new fluid machinery network configuration called variable speed auxiliary pump plus hydro turbine (VSAP-T) and establishes a mathematical model of the total output power of the fluid machinery network in CCWS to minimize network energy consumption. To illustrate the effectiveness of the VSAP-T scheme, a real system is used as the research object, and both CSAP-T and VSAP-T schemes are used to optimize the system. When the working conditions are changed, the total output power of the system fluid machinery network can be conserved by 30% to 50%.
Application of ground laser scanner in surveying and mapping field
Authors: Hu Chang’an , Hu Song , Kong Linghui , Liu Junbo 
Published: September 2021

Abstract
With the continuous development of measurement demand, the market of single point measurement mode is shrinking, 3D measurement is more and more appearing in the field of surveying and mapping, ground laser scanner as a portable 3D measurement tool, its use is more and more important. This paper takes substation measurement, cadastral measurement, facade measurement and oil tank measurement as typical cases, and introduces the case of oil tank measurement in detail.
Optimization of stereo calibration parameters for the binocular camera based on improved Beetle Antennae Search algorithm
Authors: Wang Zhaoran , Chen Guochu , Tan Lisi 
Published: September 2021

Abstract
For binocular cameras, aiming at the low precision of traditional stereo calibration methods for binocular cameras, a Beetle Antennae Search (BAS) algorithm based on binocular parallel polar line constraint was proposed to improve the calibration accuracy. The internal parameter matrix and distortion parameter matrix of the left and right cameras of the binocular camera were first calculated by using the MATLAB calibration toolbox. Then the stereo calibration parameter matrix of the binocular camera was calculated. Then, using the binocular parallel polar line constraint based on the BAS algorithm establishes the objective function by taking the difference and average values of the vertical coordinates of each checkerboard corner in the left and right images after stereo correction as the objective. The stereo calibration parameters of the binocular camera are further optimized. The results show that the BAS algorithm based on binocular parallel pole constraint is stable, reliable and fast in convergence, which can realize the optimization of stereo calibration parameters of the binocular camera.
Research and Design of Data Acquisition and Monitoring System for Intelligent Production Line of Prefabricated Building Components
Authors: Chen YaJuan , Zhou FuLiang 
Published: September 2021

Abstract
In order to solve the intelligent production and management level of assembly parts and components production line, a data acquisition and monitoring system scheme is designed to collect key parameters in the product production process, such as vibration strength (amplitude) information, concrete weight information, temperature information, humidity information, energy and other data. The scheme can realize the functions of on-site data display and processing, dynamic monitoring of equipment status and so on.
Magnetic Circuit Model of Magnetic Valve Controllable Reactor Considering Magnetic Flux Leakage Effect
Authors: Dong Liwei , Tian Mingxing , Zhang Huiying 
Published: September 2021

Abstract
The magnetic circuit model of the magnetic saturation characteristic magnetoresistance of the magnetically controlled shunt reactor (MCSR) nonlinear core is proposed by using the magnetic field division method, combining with the geometric parameters and working principle of the prototype. The magnetic circuit structure and working characteristics are analyzed. The calculation formula of the magnetic potential node of the magnetically controlled shunt reactor is derived by improving the node analysis method, and the simulation calculation and analysis of the working current of the magnetic control reactor under no-load and different DC bias are carried out. The conclusion shows that the accuracy of the magnetic circuit model can meet the needs of engineering, and the modeling method has the characteristics of clear principle, simple modeling, accurate model and engineering applicability, which can provide guidance for designers.
Matching Underwater Sonar Images by the Learned Descriptor Based on Style Transfer Method
Authors: Zhou Xiaoteng , Yu Changli , Yuan Xin , Luo Citong 
Published: September 2021

Abstract
This paper proposes a method that combines the style transfer technique and the learned descriptor to enhance the matching performances of underwater sonar images. In the field of underwater vision, sonar is currently the most effective long-distance detection sensor, it has excellent performances in map building and target search tasks. However, the traditional image matching algorithms are all developed based on optical images. In order to solve this contradiction, the style transfer method is used to convert the sonar images into optical styles, and at the same time, the learned descriptor with excellent expressiveness for sonar images matching is introduced. Experiments show that this method significantly enhances the matching quality of sonar images. In addition, it also provides new ideas for the preprocessing of underwater sonar images by using the style transfer approach.
Trajectory Clustering Of Segmented Field Operations Logistics Process
Authors: Zhang B.S. , Xiang Z.Q. , Zhang H. , Liu R. 
Published: September 2021

Abstract
It has become a new research direction to use process mining technology to mine and analyze all kinds of data generated during shipbuilding. The classification of hull segments into different clusters according to some properties in advance can make the excavation results more specific. In this paper, the process examples in ship construction are divided into different clusters based on the cohesive hierarchical clustering algorithm. Firstly, this paper introduces the advantages and disadvantages of several main clustering algorithms, selects the clustering algorithm most suitable for segmented outfield logistics, establishes the mathematical model of segmented outfield logistics process trajectory clustering, and defines the appropriate feature vectors. Euclidean distance, Hamming distance, Jekard distance and cosine distance were used to calculate the similarity distance between process instances, and the concepts of chain, single chain and group average were added to select the appropriate similarity distance between clusters. An evaluation method of clustering results based on coutour coefficient is introducedwhich can effectively evaluate the clustering results of the logistics process trajectory during segmented remote operations. Finally, the feasibility and effectiveness of the proposed algorithm are verified by experiments.
Analysis on water hammer protection of FPSO ballast water system
Authors: Li xiu , Yang hao jie , Dou pei lin , Zhao shi fa 
Published: September 2021

Abstract
In practical engineering, the protection of FPSO water hammer is very important. Through simulation analysis, the relevant data are obtained to provide reference for relevant engineering practice. A general-purpose FPSO ballast water pipe network system was established by aft impulse software, and water hammer simulation calculation and analysis were carried out to find out the maximum pressure position of water hammer phenomenon. According to the water hammer generation mechanism, the simulation research was carried out by two-stage valve closing and adding surge tank into the pipeline. It was found that water hammer was easily caused by quick closing valve; the protection method of two-stage valve closing and installation of surge tank has a very objective protective effect, which provides a reference for related projects.
Judgment and correction of lost speed Keyphasor pulse of rotating machinery
Authors: Qihe Liu 
Published: September 2021

Abstract
The order analysis of vibration signal of rotating machinery depends on the speed Keyphasor signal, and the Keyphasor pulse will be lost in actual measurement. In order to calculate the rotational speed accurately, a method to judge whether the Keyphasor pulse is lost is given, and a method to recover the lost pulse based on cubic spline interpolation is proposed. The simulation based on LabVIEW shows that the method given in this paper can well judge and recover the lost Keyphase pulse.
Study & Improvement of Occupant Out-of-position Injuries Under Pre-crash Braking Condition
Authors: Yang Jialin , Li Mengqi , Zhu Haitao 
Published: September 2021

Abstract
Although the impact strength can be reduced by AEB and other active safety technologies, the occupants may move forward under braking condition and reduce the protection space of the restraint system. The out-of-position displacement and injuries of occupants under braking conditions are studied by sled tests. The injury characteristics of the out-of-position occupant are obtained. By orthogonal tests, the influence of out-of-position on the injury of different body regions are analysed. MADYMO active human body simulation model is established, and the characteristics of the occupant forward displacement under different braking waveforms are studied by single variable method. By using the active seatbelt, the occupant’s forward displacement is restrained. With the use of Central Composite Design (CCD) method, the response surface model of the occupant’s neck displacement relative to the pretension force and pretension time of the active seatbelt is established. The effects of pretension force and pretension time on out-of-position displacement are studied, and the optimal design is carried out to obtain the parameter combination.
Infliximab for Paradoxical Reactions in Pediatric Central Nervous System Tuberculosis
Authors: Abo Yara-Natalie , Curtis Nigel , Osowicki Joshua , Haeusler Gabrielle , Purcell Rachael , Kadambari Seilesh , De Wachter Matthias , Vanden Driessche Koen , Dekeyzer Sven , Coleman Lee , Crawford Nigel , Graham Steve , Marais Ben , Gwee Amanda 
Published: September 2021

Abstract
Paradoxical reactions in central nervous system tuberculosis (CNS-TB) are associated with significant morbidity and mortality. We describe 4 HIV-uninfected children treated for CNS-TB with severe paradoxical reactions unresponsive to corticosteroids. All made recovery after treatment with infliximab, highlighting the safety and effectiveness of infliximab for this complication, and need for prospective trials.
Using a decision tool to evaluate for osteomyelitis in children
Authors: Good Jason J. , Rabener Michael J. , Fisher Geoffrey W. 
Published: September 2021

ABSTRACT
Osteomyelitis is a common occurrence in children and typically has a prolonged treatment course involving multiple specialties. Historically, the long bones are most commonly affected and Staphylococcus aureus is the primary causative organism.
This case shows the value of using the Kocher criteria and acute phase reactant C-reactive protein as diagnostic tools that can be used to advocate MRI to rule out this potentially devastating process.
Fecundity in transgender men
Authors: Salzer Elizabeth A.J. 
Published: September 2021

ABSTRACT
Premenopausal transgender men who retain internal female reproductive organs, who use exogenous testosterone, and who are sexually active with cisgender men are often capable of conception. This article discusses the potential for fecundity in transgender men, as well as appropriate reproductive care depending on whether the patient prefers to avoid conception or to become pregnant.
Outcomes After Operative Fixation of Vancouver B2 and B3 Type Periprosthetic Fractures
Authors: Barghi Ameen , Hanna Philip , Merchan Nelson , Lechtig Aron , Haggerty Christopher , Weaver Michael J. , von Keudell Arvind , Wixted John , Appleton Paul , Rodriguez Edward 
Published: September 2021

Objectives:
The incidence of periprosthetic femur fracture in the setting of total hip arthroplasty is steadily increasing. Although the traditional dogma is that loose femoral components must be revised, we propose that in a frail geriatric population, anatomic reduction and fixation of Vancouver B2 and B3 periprosthetic fracture variants can restore stem stability and provide similar outcomes as revision arthroplasty.

Design:
Retrospective cohort study.

Setting:
Level 1 trauma center, tertiary academic medical center.

Patients/Participants:
We identified 94 patients over 65 years of age with Vancouver B2 and B3 fractures sustained between 2005 and 2019.

Intervention:
Patients were treated by either open reduction and internal fixation (ORIF) or revision arthroplasty (RA) with or without fixation.

Main Outcome Measurements:
Outcomes were mortality, time to full weight-bearing after surgery, intraoperative estimated blood loss, perioperative complications, reoperation, subsidence rate, and Patient-Reported Outcomes Measurement Information System pain and physical function scores.

Results:
A total of 75 (79.8%) ORIF and 19 (20.2%) RA patients were reviewed. One-year mortality for our cohort was 26.3%, and there was no significant difference between groups. Mean time to weight bear and surgical complication rates were similar between groups. The ORIF group had a significantly shorter time to surgery than the RA group. The RA group had greater incidence and amount of subsidence as well as estimated blood loss than the ORIF group.

Conclusions:
In geriatric patients with Vancouver B2 and B3 type periprosthetic fractures with known loose stems, ORIF may offer a similarly safe method of treatment than revision arthroplasty.

Level of Evidence:
Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.