bluuebunny/crossref_metadata_2025_split huggingface dataset:
Feasibility Study of the One-Dimensional Radiation Distribution Sensing Method Using an Optical Fiber Sensor Based on Wavelength Spectrum Unfolding
Authors: Terasaka Yuta , Watanabe Kenichi , Uritani Akira , Yamazaki Atsushi , Sato Yuki , Torii Tatsuo , Wakaida Ikuo 
Published: October 2020

Abstract
We propose a novel one-dimensional radiation distribution sensing method using an optical fiber sensor based on wavelength spectrum unfolding for the application in the measurement of the high dose rate hot spots inside the Fukushima Daiichi nuclear power station (FDNPS) buildings. The proposed method estimates the incident position of radiation to the fiber by the unfolding of wavelength spectrum output from the fiber edge on the premise that the attenuation length of light along the fiber depends on a wavelength. Because this method measures integrated light intensity, it can avoid the problem of counting loss and signal pile-up, which occurs in a radiation detector with the pulse counting mode under the high dose rate field. Basic properties of source position detection were confirmed through basic experiments using an ultraviolet light source and 90Sr/90Y radioactive point source.
Electrochemical Stability and Performance of Li2OHCl Substituted by F or Br as Solid-State Electrolyte
Authors: Lee Yong-Seok , Jung Su-Yeon , Ryu Kwang-Sun 
Published: October 2020

Abstract
Li2(OH)0.9F0.1Cl, Li2(OH)0.9Br0.1Cl, and Li2OHCl0.8Br0.2 solid electrolytes were synthesized and compared with Li2OHCl to analyze the exact improvement mechanism for Li+ conductivity and electrochemical stability of Li2OHX-type solid electrolyte. The substituted materials exhibit improved electrochemical stability and Li+ conductivity Li2OHCl. Among these materials, Li(OH)0.9F0.1Cl has improved Li+ conductivity due to a reduction of the OH– concentration and the conductivity of Li2OHCl0.8Br0.2 was also increased compared with Li2OHCl due to the large interstitial site. In the case of Li2(OH)0.9Br0.1Cl, it had the highest Li+ conductivity and good Li+ migration by both effects because of a larger interstitial site and low OH− concentration. Furthermore, the electrochemical stability of four materials was compared due to the different structural stabilities and strengths of binary chemical bonds such as Li–X, H–X, and O–X. Comparing the Li+ conductivity of Li2(OH)0.9F0.1Cl and Li2OHCl0.8Br0.2, the Li+ conductivity is influenced by the OH− concentration unlike the other mechanisms.
Experimental Study on Deteriorated Performance, Vibration, and Geometry Changes of an Electrical Submersible Pump Under Sand Water Flow Condition
Authors: Zhu Haiwen , Zhu Jianjun , Rutter Risa , Zhang Hong-Quan 
Published: October 2020

AbstractIn the oil and gas industry, the proppant backflow from fracturing wells severely reduces the lifespan of widely used downhole electrical submersible pumps (ESPs). In field applications, a minimal sand concentration may cause severe damage to ESPs in a short time. In order to resist the three-body abrasive sand wear, flanged tungsten carbide sleeves are used in ESPs. However, the wear-resistant performance of different pump geometry is not well analyzed and understood. Therefore, a 64 h pump erosion and abrasion test was conducted with water at the pump's best efficient flowrate with a sand concentration of 1 wt% to imitate the damage caused by short-term proppant backflow. The test was divided into several periods, after which the pump performance, paint-removal wear pattern, eroded pump geometries, and stage vibration were measured and recorded. The wear-rate on pump stage geometries gradually decreased at the beginning of 8–16 h. Then, the carbide sleeves started to help sustain the pump rotation. As a result, the wear-rate and pump vibration became relatively stable. Therefore, the wear mechanism in the secondary flow region (seal rings and sleeves) is believed to change from abrasive wear to the combined erosive-abrasive wear. The pump overall performance decreased by approximately 10% after the 64 h test. The performance, pump geometry, and vibration data are previous for understanding wear mechanism, predicting failures, improving pump design, and saving the well service cost.
A Novel Model-Based Steering Control for Hydra-Power Articulated Steering Vehicles
Authors: Gao Lulu , Jin Chun , Liu Yuchao , Ma Fei , Feng Zhipeng 
Published: October 2020

Abstract
The hydra-power articulated steering vehicles possess brilliant maneuverability and efficiency, and they were widely applied in mining, construction, agriculture, and forestry. However, the steering characteristic also deduced a serious handling stability problem of this type of vehicle, i.e., oscillation in yaw motion. Previous research only analyzed the stability of the vehicle dynamical system or provided a passive structural method to suppress the oscillation of articulated vehicles. This work presents a novel model-based steering control of articulated steering vehicles. A coupled nonlinear dynamic model was established firstly, in which nonlinear models of the hydraulic system and dynamic model of articulated frames were included. Then the coupled model was validated in time and frequency domain by a field test. The susceptibility of different factors of the system oscillation was investigated by simulation based on the validated model. On this foundation, an optimized scheme of the hydraulic steering system was provided. Further a novel control strategy, in which the articulation angle and corresponding angular velocity were considered together as the control variables of the system, was embedded into the optimized system. Comparing results in dynamic responses of articulated frames, ripples in the hydraulic steering system shown the effectiveness and superiority of the presented method.
Analogy Between Hydraulic Transformers and Variable-Speed Pumps
Authors: Schmidt Lasse , Ketelsen Søren , Mommers Robin , Achten Peter 
Published: October 2020

Abstract
The increasing focus on energy efficient systems and energy recuperation functionalities calls for multi actuator hydraulic systems to be tightly integrated with regards to energy distribution. Such systems need to allow power to pass back and forth between loads and the supply, while also enabling the ability to store energy. Here two approaches are obvious; namely the usage of hydraulic transformers interconnected via common pressure rails containing accumulators, and variable-speed pumps interconnected via a common electric dc-bus containing capacitors and/or batteries, both having the potential for energy storage and power sharing. A main question is when to apply which of these technologies, when considering specific requirements to actuator dynamics and control features. This paper presents an investigation into the analogy between hydraulic transformers and variable-speed pumps. The investigation takes offset in model based analyses of these technologies regarding their actuation dynamics related to torque generation, input-to-output pressure dynamics with and without a cylinder load. Finally a numerical study is presented, verifying and comparing their transient characteristics and energy losses. It is found that, disregarding the conventional speed control loop in variable-speed pumps, these are in fact equivalent with hydraulic transformers regarding secondary control abilities, dynamics and energy recovery, wheres hydraulic transformers generally must be expected to be more efficient than variable-speed pumps.
Tribotronics in Electro-Hydraulic Actuator Technology: Improving Durability by Control
Authors: Grønkær Nikolaj , Johansen Per , Hansen Kenneth Vorbøl , Schmidt Lasse 
Published: October 2020

Abstract
A trend in industry and academia is the design of variable-speed pump drives for use in hydraulic supply units, actuation of hydraulic cylinders and so forth, due to the potential of highly limited throttling. A main drawback in existing variable-speed pump drives is the operation of pumps at high loads and low shaft speeds, potentially increasing wear in pump bearings, especially in pumps with journal bearings. Such journal bearings rely on hydrodynamic lubrication films created by the rotation of the pump, which is minimised or removed completely when the pump shaft speed is in the lower range with a high load. The purpose of the study presented is to investigate how these conditions limit the operation of variable-speed pump drives, and how these challenges may be overcome. The study takes offset in the establishment of a wear rate constructed from a risk factor in the form of the Ocvirk number and an impact factor developed from Archard’s wear law. With this wear rate, a novel control method targeting the best possible operating conditions for the pump bearings is proposed, when applied to a simple variable-speed drive. Lastly, the consequence of applying the proposed control method on the energy efficiency is investigated. Numerical results demonstrate that the proposed control method reduces the wear rate and hereby the risk of an early pump failure, however, on the cost of a generally reduced energy efficiency.
Underwater Flexible Manipulator Double-Loop Feedback Control Based on Built-in Binocular Vision and Displacement Sensor
Authors: Yang Chen , Xu He , Li Xin , Wang Haihang , Yu Fengshu 
Published: October 2020

Abstract
A real-time and effective double-loop feedback control system for underwater flexible manipulators is raised in this paper. The research object is a kind of underwater flexible manipulator driven by McKibben water hydraulic artificial muscle (WHAM) that can grasp, swallow, and disgorge target objects in its interior space. To make up for the lack of flexibility, an underwater flexible manipulator collaborative working strategy is proposed. A more flexible and smaller flexible manipulator is placed inside the flexible manipulator to assist it in performing difficult underwater works. The control system feeds back the position of internal objects through a built-in binocular camera and the working state of the manipulator through displacement sensors. The control system setups including underwater flexible manipulator subsystem, hydraulic drive subsystem, PLC control subsystem, displacement sensor subsystem, built-in binocular vision subsystem, and upper computer subsystem is built. PYTHON-based built-in binocular vision software and C++-based underwater flexible manipulator control software are also developed to facilitate observation and recording. The underwater flexible manipulator collaborative experiment is designed to verify the performance of the control system and the control algorithm.
Review of Gear Pump Development at NRL
Authors: Williams Logan T. 
Published: October 2020

Abstract
Research into hydraulic quadrupeds at the US Naval Research Laboratory (NRL) has created the demand for in-house development of miniaturized hydraulic components, including pumps. As part of this effort to develop a miniaturized hydraulic powertrain, external gear pumps were examined, designed, and iterated upon to create an efficient pump package with a small form factor (1.5 × 1.6 × 1.8 inches). The evolution of the pump design has touched every component of the pump and has resulted in many practical design guidelines, novel pump components, and improved pump analysis tools. The original goal of developing the capability for integrated hydraulic powertrain components, such as embedding the pump into the quadruped’s hydraulic manifold, was to enable further compaction and streamlined system development. An additional result of the project was the accumulation of gear pump design fundamentals and lessons learned that can benefit any pump designer.
Demonstration of Efficient Energy Recovery Systems Using Digital Displacement® Hydraulics
Authors: Hutcheson John , Abrahams Daniel , Macpherson Jill , Caldwell Niall , Rampen Win 
Published: October 2020

Abstract
Heavy off-road vehicles using conventional hydraulic systems waste significant energy through the throttling of fluid to control the motion of their actuators. This paper demonstrates how Digital Displacement® Pump Motors (DDPMs) can be used to enable efficient hydraulic energy recovery systems for these vehicles by controlling the motion of actuators directly without the need of throttling.
Experiments were carried out on a test rig consisting of a 10 tonne boom supported by a hydraulic ram designed to mimic the setup of a heavy off-road vehicle. In order to demonstrate the DDPM’s potential for energy recovery systems the round-trip efficiency was measured by lifting and lowering the boom. The round-trip efficiency was taken to be the ratio of the mechanical energy output from the DDPM, when motoring to lower the boom, to the mechanical energy input to the DDPM, when pumping to raise the boom, over a known ram extension. The results showed measured round-trip efficiencies of between 63% and 87% over a range of pressures, shaft speeds and displacement fractions.
Measured data obtained during the test was used to simulate the test using different system architectures and components to determine the energy efficiency. Both load sense and displacement controlled systems were simulated using both swashplate and Digital Displacement pumps. Comparison showed that the Digital Displacement systems used between 1.1 and 10.8 times less energy than the equivalent swashplate based systems. This work forms the basis for further development of energy recovery system architectures using DDPMs. Future challenges include development of the actuator control valves and transformers required to implement such systems.
Energy Efficient Excavator Hydraulic Systems With Digital Displacement® Pump-Motors and Digital Flow Distribution
Authors: Macpherson Jill , Williamson Christopher , Green Matthew , Caldwell Niall 
Published: October 2020

Abstract
Environmental and economic factors are driving the development of more fuel efficient off-highway vehicles. The pathway to fuel savings of greater than 50% in an excavator application through utilisation of system architectures unlocked by Digital Displacement technology is presented.
Pump flow distribution using digital valves instead of traditional proportional control valves is demonstrated experimentally. The “Workbus” power distribution scheme is demonstrated on a small scale backhoe arm on a laboratory test rig. These tests do not include hydraulic energy recovery.
A backward-facing simulation of an 18 tonne excavator is described. The simulation uses input data collected from grading and lorry loading duty cycles. Applying the workbus system architecture to the excavator in simulation, fuel savings of 31% to 48% are realized. With the addition of energy recovery capability via Digital Displacement Pump-Motors, simulated fuel savings are 53% to 58% compared to the original excavator hydraulic system.
Optimal Control and Energy-Saving Analysis of Common Pressure Rail Architectures: HHEA and STEAM
Authors: Siefert Jacob , Li Perry Y. 
Published: October 2020

Abstract
In recent years several novel hydraulic architectures have been proposed with the intention of significantly increasing system efficiency. Two of these architectures, Steigerung der Energieefflzienz in der Arbeitshydraulik mobiler Arbeitsmaschinen (STEAM), and the Hybrid Hydraulic-Electric Architecture (HHEA), use a system of multiple common pressure rails (CPRs) to serve the multiple degrees-of-freedom of the machine. The key difference is that STEAM throttles hydraulic power from these rails while HHEA combines electric and hydraulic power to meet actuator demands. As a throttle-less architecture, HHEA is expected to save more energy than STEAM at the expense of added complexity. Therefore, it is useful to quantify this additional energy saving.
Both systems have discrete operational choices corresponding to how the CPRs are utilized for each actuator. It is necessary to determine optimal operation for each of these architectures for analysis and fair comparison. Techniques for optimal operation of the HHEA have been developed previously from the Langrange multiplier method. Applying the same optimal control method to STEAM encountered some technical challenge leading to the optimal control algorithm not being able to satisfy certain constraints. The issue is analyzed and solved by adding noise to the optimization.
Using this proposed algorithm, case studies are performed to compare the energy-saving potentials of STEAM and HHEA for two sizes of excavators and a wheel-loader performing representative duty cycles. The baseline is a standard load-sensing architecture. Results show that STEAM and HHEA can reduce energy consumption between 35–65% and 50–80% respectively.
Hydraulic Effort and the Efficiencies of Pump and Motors With Compressible Fluid
Authors: Li Perry Y. , Barkei Jonathan (Hans) 
Published: October 2020

Abstract
When hydraulic fluid is compressible, the usual formula of hydraulic power being the product of pressure (p) and volumetric flow Q, which accounts only for the flow work, is not sufficient. By deriving an explicit formula for the stored compressible energy in accordance with the possibly pressure-dependent bulk modulus, a hydraulic effort (with symbol Φ) is defined to be the sum of the fluid pressure and the compressible energy density at that pressure. It is shown that Φ is the conjugate variable to volumetric flow (Q) such that that the compressible hydraulic power flow is the product Φ(p)Q.
With proper understanding of compressible hydraulic power flow, the ideal relationships of pumps and motors with compressible fluid are then derived. These differ from incompressible formulae by replacing p by Φ and identifying an appropriate displacement. From these, definitions for mechanical efficiency, volumetric efficiency, and power efficiency are obtained. Unlike the previous attempts, these definitions are mutually consistent in that the product of mechanical and volumetric efficiencies is indeed the power efficiency. Furthermore, they are exact and are suitable even if the bulk modulus is pressure dependent.
To gain insights into these new efficiency definitions, various modes of non-ideal effects in a piston pump/motor with variable valve timing are modeled and their effects on the mechanical, volumetric and power efficiencies are obtained. These non-ideal effects include piston-bore friction, leakage, valve throttling, and non-ideal valve timing.
Sex differences in circulating leptin as a marker of adiposity in obese or overweight adolescents with type 1 diabetes
Authors: Redondo Maria J , Siller Alejandro F , Gu Xiangjun , Tosur Mustafa , Bondy Melissa , Devaraj Sridevi , Sisley Stephanie 
Published: October 2020

IntroductionWe aimed to test whether the serum adipokines leptin and adiponectin are more strongly associated with body fat percentage (BF%) than body mass index (BMI) in adolescents with type 1 diabetes (T1D) and overweight/obesity.Research design and methodsWe studied all participants in the T1D Exchange Metformin Study (n=122, median age 12.9 years, range 12–19.5; 32% males; 77% non-Hispanic whites, 100% overweight or obesity; median diabetes duration 6.7 years, range 1.4–15) with a baseline serum sample where we measured leptin and adiponectin concentrations. Anthropometric, clinical, laboratory and dual-energy X-ray absorptiometry (DEXA) scan measurements were analyzed. We compared correlation coefficients between variables of interest.ResultsBF% by DEXA was significantly correlated with BMI Z-score (r=0.38, p<0.0001), BMI per cent of the 95th percentile (BMI%95) (r=0.45, p<0.0001), waist circumference (r=0.46, p<0.0001), leptin (r=0.58, p<0.00001) and leptin/adiponectin ratio (r=0.36, p<0.0001), while it was not significantly correlated with absolute body weight, adiponectin or insulin dose (total or basal). BF% was significantly more strongly correlated with leptin than with BMI Z-score in the overall group (p=0.022). However, there were sex-based differences. Among the significant correlations in the overall group, BF% was most strongly associated with leptin (r=0.75) in boys (n=39) but with waist circumference (r=0.58) in girls (n=83) (all p<0.0001).ConclusionsSerum leptin could be used as a surrogate convenient marker of adiposity in overweight/obese adolescent boys with T1D, equivalent to BMI Z-score or BMI%95. In girls, waist circumference was the best performing marker overall, and was also strongly correlated with %BF in boys.
Not just money: what mothers value in conditional cash transfer programs in India
Authors: Rao Krishna D , Kachwaha Shivani , Kaplan Avril , Bishai David 
Published: October 2020

IntroductionConditional cash transfers (CCTs) have become an important policy tool for increasing demand for key maternal and child health services in low/middle-income countries. Yet, these programs have had variable success in increasing service use. Understanding beneficiary preferences for design features of CCTs can increase program effectiveness.MethodsWe conducted a Discrete choice experiment in two districts of Uttar Pradesh, India in 2018 with 405 mothers with young children (<3 years). Respondents were asked to choose between hypothetical CCT programme profiles described in terms of five attribute levels (cash, antenatal care visits, growth-monitoring and immunisation visits, visit duration and health benefit received) and responses were analysed using mixed logit regression.ResultsMothers most valued the cash transfer amount, followed by the health benefit received from services. Mothers did not have a strong preference for conditionalities related to the number of health centre visits or for time spent seeking care; however, service delivery points were in close proximity to households. Mothers were willing to accept lower cash rewards for better perceived health benefits—they were willing to accept 2854 Indian rupees ($41) less for a programme that produced good health, which is about half the amount currently offered by India’s Maternal Benefits Program. Mothers who had low utilisation of health services, and those from poor households, valued the cash transfer and the health benefit significantly more than others.ConclusionBoth cash transfers and the perceived health benefit from services are highly valued, particularly by infrequent service users. In CCTs, this highlights the importance of communicating value of services to beneficiaries by informing about health benefits of services and providing quality care. Conditionalities requiring frequent health centre visits or time taken for seeking care may not have large negative effects on CCT participation in contexts of good service coverage.