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Prediction of net energy of feeds for broiler chickens

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Animal Nutrition 2024年第1期16卷 241-250页

作者： Aye-Cho Tay-Zar Manoosak Wongphatcharachai Pairat Srichana Pierre-André Geraert Jean Noblet Charoen Pokphand Foods Public company limited (CPF) Adisseo France S.A.S. INRAE

Net energy(NE) enables the prediction of more accurate feed energy values by taking into account the heat increment which is approximately 25% of apparent metabolizable energy(AME) in ***, application of NE in poultry industry has not been practiced widely. To predict the NE values of broiler diets, 23 diets were prepared by using 13 major ingredients(wheat, corn, paddy rice,broken rice, cassava pellets, full-fat soybean, soybean meal, canola meal, animal protein, rice bran, wheat bran, palm kernel meal and palm kernel oil). The diets were formulated in order to meet the birds' requirements and get a wide range of chemical compositions(on DM basis; 33.6% to 55.3% for starch;20.8% to 28.4% for CP, 2.7% to 10.6% for ether extract [EE] and 7.0% to 17.2% for NDF), with low correlations between these nutrients and low correlations between the inclusion levels of ingredients allowing for the calculation of robust prediction equations of energy values of diets or ingredients. These diets were fed to Ross 308 broilers raised in 12 open-circuit respiratory chambers from 18 to 23 d of age(4 birds per cage) and growth performance, diet AME content and heat production were measured, and dietary NE values were calculated. The trial was conducted on a weekly basis with 12 diets measured each week(1per chamber), 1 of the 23 diets(reference diet) being measured each week. Each diet was tested at least 8times. In total, 235 energy balance data values were available for the final calculations. Growth performance, AME(15.3 MJ/kg DM on average) and AME/GE(79.4% on average) values were as expected. The NE/AME value averaged 76.6% and was negatively influenced by CP and NDF and positively by EE in connection with efficiencies of AME provided by CP, EE and starch for NE of 73%, 87% and 81%,respectively. The best prediction equation was: NE =(0.815 × AME)—(0.026 × CP) +(0.020 × EE)—(0.024 × NDF) with NE and AME as MJ/kg DM, and CP, EE and NDF as % of DM. The NE prediction

关键词： Net energy Broiler Poultry Feed evaluation Energy system

Fracture behavior and mechanism of highly fragmented steel cylindrical shell under explosive loading

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Defence Technology（防务技术） 2024年第6期36卷 122-132页

作者： Kang Wang Peng Chen Xingyun Sun Yufeng Liu Jiayu Meng Xiaoyuan Li Xiongwei Zheng Chuan Xiao Xi'an Modern Chemistry Research Institute Xi'an 710065China Shanxi Jiangyang Chemical company limited Taiyuan 030051China Central Iron&Steel Research Institute company limited Beijing 100081China China Research and Development Academy of Machinery Equipment Beijing 100089China

An in-depth understanding of the fracture behavior and mechanism of metallic shells under internal explosive loading can help develop material designs for warheads and regulate the quantity and mass distribution of the fragments *** study investigated the fragmentation performance of a new high-carbon silicon-manganese(HCSiMn)steel cylindrical shell through fragment recovery *** with the conventional 45Cr steel shell,the number of small mass fragments produced by the HCSi Mn steel shell was significantly increased with a scale parameter of 0.57 g fitted by the Weibull distribution *** fragmentation process of the HCSi Mn shell exhibited more brittle tensile fracture characteristics,with the microcrack damage zone on the outer surface being the direct cause of its high *** the one hand,the doping of alloy elements resulted in grain refinement by forming metallographic structure of tempered sorbite,so that microscopic intergranular fracture reduces the characteristic mass of the fragments;on the other hand,the distribution of alloy carbides can exert a"pinning"effect on the substrate grains,causing more initial cracks to form and propagate along the brittle carbides,further improving the shell *** the killing power radius for light armored vehicles was slightly reduced by about 6%,the dense killing radius of HCSiMn steel projectile against personnel can be significantly increased by about 26%based on theoretical *** results provided an experimental basis for high fragmentation warhead design,and to some extent,revealed the correlation mechanism between metallographic structure and shell fragmentation.

关键词： Projectile fragmentation Fragment mass distribution Fracture mode Metallographic structure Damage power

Integrated Frequency-constrained Scheduling Considering Coordination of Frequency Regulation Capabilities from Multi-source Converters

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 261-274页

作者： Jiaming Li Ying Qiao Zongxiang Lu Wei Ma Xin Cao Rongfu Sun the Department of Electrical Engineering Tsinghua UniversityBeijing 100084China the China Suntien Green Energy limited company Shijiazhuang 050011China the State Grid Jibei Electric Power company Beijing 100054China

As the proportion of renewable energy(RE)increases,the inertia and the primary frequency regulation(FR)capability of the power system ***,ensuring frequency security in the scheduling model has become a new technical requirement in power systems with a high share of *** to a shortage of conventional synchronous generators,the frequency support of multi-source converters has become an indispensable part of the system frequency resources,especially variable-speed wind turbine generation(WTG)and battery energy storage(BES).Quantitative expression of the FR capability of multi-source converters is necessary to construct frequency-constrained scheduling ***,the frequency support performance of these converter-interfaced devices is related to their working states,operation modes,and parameters,and the complex coupling of these factors has not been fully exploited in existing *** this study,we propose an integrated frequency-constrained scheduling model considering the coordination of FR capabilities from multi-source *** FR control strategies and variable FR parameters for WTG with or without reserved power are modeled,and multi-target allocation of BES capacity between tracking dispatch instruction and emergency FR is ***,the variable FR capabilities of WTG and BES are embedded into the integrated frequency-constrained scheduling *** nonlinear constraints for frequency security are precisely linearized through an improved iteration-based *** effectiveness of the proposed model is verified in a modified IEEE 24-bus standard *** results suggest that the coordinated participation of BES and WTG in FR can effectively reduce the cost of the scheduling model while meeting frequency security constraints.

关键词： Battery energy storage(BES) wind turbine generation(WTG) frequency regulation(FR) frequency security power system scheduling

A multichannel thermal bubble-actuated impedance flow cytometer with on-chip TIA based on CMOS-MEMS

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Journal of Semiconductors 2024年第5期45卷 41-49页

作者： Shengxun Cai Jianqing Nie Kun Wang Yimin Guan Demeng Liu School of Microelectronics Shanghai UniversityShanghai 201800China Shanghai AURE Technology limited company Shanghai 201800China

Electrochemical impedance spectroscopy(EIS)flow cytometry offers the advantages of speed,affordability,and portability in cell analysis and cytometry ***,the integration challenges of microfluidic and EIS read-out circuits hinder the downsizing of cytometry *** address this,we developed a thermal-bubble-driven impedance flow cytometric application-specific integrated circuit(ASIC).The thermal-bubble micropump avoids external piping and equipment,enabling high-throughput *** a total of 36 cell counting channels,each measuring 884×220μm^(2),the chip significantly enhances the throughput of flow *** cell counting channel incorporates a differential trans-impedance amplifier(TIA)to amplify weak biosensing *** eliminating the parasitic parameters created at the complementary metal-oxidesemiconductor transistor(CMOS)-micro-electromechanical systems(MEMS)interface,the counting accuracy can be *** on-chip TIA can adjust feedback resistance from 5 to 60 kΩto accommodate solutions with different *** chip effectively classifies particles of varying sizes,demonstrated by the average peak voltages of 0.0529 and 0.4510 mV for 7 and 14μm polystyrene beads,***,the counting accuracies of the chip for polystyrene beads and MSTO-211H cells are both greater than 97.6%.The chip exhibits potential for impedance flow cytometer at low cost,high-throughput,and miniaturization for the application of point-of-care diagnostics.

关键词： EIS flow cytometry CMOS-MEMS thermal bubble lab-on-chip

Distal-scanning common path probe for optical coherence tomography

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Journal of Innovative Optical Health Sciences 2024年第3期17卷 84-92页

作者： Zhengyu Chen Bin He Zichen Yin Zhangwei Hu Yejiong Shi Chengming Wang Xiao Zhang Ning Zhang Linkai Jing Guihuai Wang Ping Xue State Key Laboratory of Low-dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijingChina Frontier Science Center for Quantum Information BeijingChina jinsp company limited BeijingChina Beijing Institute of Technology BeijingChina Institute of Forensic Science Ministry of Public Security BeijingChina Department of Neurosurgery Beijing Tsinghua Changgung HospitalSchool of Clinical Medicine and Institute of Precision MedicineTsinghua UniversityBeijingChina

In this paper,we present a distal-scanning common path probe for optical coherence tomography(OCT)equipped with a hollow ultrasonic motor and a simple and specially designed *** novel probe proves to be able to effectively circumvent polarization and dispersion mismatch caused by fiber motion and is more robust to a variety of interfering factors during the imaging process,experimentally compared to a conventional noncommon path ***,our design counteracts the attenuation of backscattering with depth and the fall-off of the signal,resulting in a more balanced signal range and greater imaging ***-domain OCT imaging of phantom and biological tissue is also demonstrated with a sensitivity of∼100dB and a lateral resolution of∼3μ*** low-cost probe offers simplified system configuration and excellent robustness,and is therefore particularly suitable for clinical diagnosis as one-off medical apparatus.

关键词： Common path optical coherence tomography endoscopic probe

Naive-LSTM enabled service identification of edge computing in power internet of things

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The Journal of China Universities of Posts and Telecommunications 2024年

作者： Bai Huifeng Huo Chao Zhang Ganghong Yin Zhibin Beijing SmartChip Microelectronics Technology company limited

Great challenges and demands are presented by increasing edge computing services for current Power Internet of Things (Power IoT) to deal with serious diversity and complexity of these services. To improve the matching degree between edge computing and complex services， the services identification function is necessary for Power IoT. This article proposes a naive long short-term memory (Naive-LSTM) based services identification scheme of edge computing devices in the Power IoT， where the Naive-LSTM model makes full use of the most simplified structure and conducts discretization of the LSTM model. Moreover， the Naive-LSTM based services identification scheme can generate the probability output result to determine the task schedule police of Power IoT. After well learning operation， these Naive-LSTM classification engine module in edge computing devices of Power IoT can perform services identification， by obtaining key characteristics from various services traffics. Testing results show that the Naive-LSTM based services identification scheme is feasible and efficient in improving the edge computing ability of the Power IoT.

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Fracture geometry and breakdown pressure of radial borehole fracturing in multiple layers

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Petroleum Science 2024年第1期21卷 430-444页

作者： Yu-Ning Yong Zhao-Quan Guo Shou-Ceng Tian Lu-Yao Ma Tian-Yu Wang Mao Sheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Beijing Petroleum Machinery company limited CNPC Engineering Technology R&D Company LimitedBeijing102206China Smart Energy Co. LtdChina Xiongan GroupXiong’an New Area071000HebeiChina

Radial borehole fracturing that combines radial boreholes with hydraulic fracturing is anticipated to improve the output of tight oil and gas *** paper aims to investigate fracture propagation and pressure characteristics of radial borehole fracturing in multiple layers.A series of laboratory experiments with artificial rock samples(395 mm×395 mm×395 mm)was conducted using a true triaxial fracturing *** crucial factors corresponding to the vertical distance of adjacent radial borehole layers(vertical distance),the azimuth and diameter of the radial borehole are *** results show that radial borehole fracturing in multiple layers generates diverse fracture *** types of fractures are identified based on the connectivity between hydraulic fractures and radial *** vertical distance significantly influences fracture propagation perpendicular to the radial borehole *** increase in the vertical distance impedes fracture connection across multiple radial borehole layers and reduces the fracture propagation distance along the radial borehole *** azimuth also influences fracture propagation along the radial borehole *** the azimuth reduces the guiding ability of radial boreholes,which makes the fracture quickly curve to the maximum horizontal stress *** breakdown pressure correlates with diverse fracture geometries *** the fractures connect multi-layer radial boreholes,increasing the vertical distance decreases the breakdown *** the azimuth and increasing the diameter also decrease the breakdown *** extrusion force exists between the adjacent fractures generated in radial boreholes in multiple rows,which plays a crucial role in enhancing the guiding ability of radial boreholes and results in higher breakdown *** research provides valuable theoretical insights for the field application of radial borehole fracturing technology in tight oil and g

关键词： Multi-layer radial boreholes Hydraulic fracturing Fracture propagation Pressure characteristic

Non-intrusive Load Monitoring Based on Graph Total Variation for Residential Appliances

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 947-957页

作者： Xiaoyang Ma Diwen Zheng Xiaoyong Deng Ying Wang Dawei Deng Wei Li the College of Electrical Engineering Sichuan UniversityChengdu 610065China State Grid Chongqing Electric Power company Chongqing 400014China State Grid Sichuan Electric Power company Chengdu 610095China State Grid Hubei Electric Power company limited Research Institute Wuhan 430077China

Non-intrusive load monitoring is a technique for monitoring the operating conditions of electrical appliances by collecting the aggregated electrical information at the household power *** several studies on the mining of unique load characteristics,few studies have extensively considered the high computational burden and sample *** on lowfrequency sampling data,a non-intrusive load monitoring algorithm utilizing the graph total variation(GTV)is proposed in this *** algorithm can effectively depict the load state without the need for prior ***,the combined Kmeans clustering algorithm and graph signals are used to build concise and accurate graph structures as load *** GTV representing the internal structure of the graph signal is introduced as the optimization model and solved using the augmented Lagrangian iterative *** introduction of the difference operator reduces the computing cost and addresses the inaccurate reconstruction of the graph *** low-frequency sampling data,the algorithm only requires a little prior data and no training,thereby reducing the computing *** conducted using the reference energy disaggregation dataset and almanac of minutely power dataset demonstrated the stable superiority of the algorithm and its low computational burden.

关键词： Non-intrusive load monitoring graph total variation augmented Lagrangian function smart grid

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

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Petroleum Science 2024年第3期21卷 2048-2065页

作者： Qing-Ping Li Jin-Ya Zhang Jia-Xiang Zhang Yong-Xue Zhang CNOOC Research Institute company limited State Key Laboratory of Natural Gas Hydrate College of Mechanical and Transportation Engineering China University of Petroleum

Slug flow or high GVF(Gas Volume Fraction) conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps, endangering the safety of multiphase pump units. The mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation model. UDF(User Define Function) programs such as structural dynamics equations, alternating load equations, and pressure disturbance equations are embedded in numerical calculations, and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh technology. The results show that when the pressure disturbance occurs at the inlet, as the amplitude and period of the disturbance increase, the film thickness gradually decreases. And the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely manner. The maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance amplitude. The mutual interference between enhanced waves does not have a significant impact on the film thickness, while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes, and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial values. Compared with pressure disturbance conditions, alternating load conditions have a more significant impact on film thickness and leakage. During actual operation, it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump Liquid film seal Pressure disturbance wave Dynamic response characteristics