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Design and experimental study of the SPKM165, a five-axis serial-parallel kinematic milling machine

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Science China(Technological Sciences) 2011年第5期54卷 1193-1205页

作者： XIE FuGui LIU XinJun ZHANG Hui wang jinsong State Key Laboratory of Tribology & Institute of Manufacturing Engineering Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

A five-axis serial-parallel kinematic milling machine, the SPKM 165, is introduced. This machine consists of a three-degree of-freedom parallel module and a two-degree-of-freedom serial table. The SPKM 165 is capable of five-face machining. A discussion of the inverse kinematics of the five-axis control is provided. A dimensional synthesis procedure is presented in terms of motion/force transmissibility. Finite-element analysis was used to evaluate the stiffness of a CAD model before the machine was manufactured. Kinematic calibration was implemented to improve the accuracy of the end effector. The results of a calibration experiment are presented. The stiffness of the developed machine was then measured. Milling experiments were conducted, and the test piece showed that the developed machine has satisfactory performance.

关键词： serial-parallel kinematic machine dimension synthesis stiffness evaluation kinematic calibration

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临床与实验病理学杂志 2024年第4期40卷 396-401页

作者：张爱朱宁杨路路方媛王劲松李俐南京医科大学附属南京医院(南京市第一医院)病理科南京210006

目的分析结直肠癌(colorectal cancer,CRC)中CD66b^(+)肿瘤相关中性粒细胞(tumor-associated neutrophils,TANs)和促纤维间质反应(desmoplastic reaction,DR)分类情况,探讨CD66b^(+)TANs和DR在CRC中的临床病理学意义及预后价值。方法采用免疫组化法检测240例CRC中CD66b^(+)TANs的表达数量,应用HE染色切片观察肿瘤间质DR的分类,并分析CD66b^(+)TANs和DR分类与CRC临床病理特征的关系;利用Kaplan-Meier生存曲线分析CD66b^(+)TANs和DR分类与CRC患者预后的关系。结果240例CRC中,CD66b^(+)TANs丰富型(NR)组29例,CD66b^(+)TANs中间型(NI)/缺乏型(NP)组211例;DR分类中,成熟型92例,中间型63例,不成熟型85例。CD66b^(+)TANs NR组与较高的组织学分级(P=0.034)、更晚的TNM分期(P=0.006)和脉管侵犯(P=0.002)均有关。CRC中DR分类与肿瘤分化程度、神经侵犯、淋巴结转移和pTNM分期均密切相关(P<0.05),DR不成熟型CRC分化程度低、有神经侵犯和淋巴结转移、更晚的pTNM分期。Kaplan-Meier生存分析显示,与CD66b^(+)TANs NI/NP CRC患者相比,CD66b^(+)TANs NR CRC患者的3年总生存率明显降低(P<0.05);多因素分析显示:高TANs是CRC的独立预后因素(P<0.05)。DR不成熟型CRC患者的3年总生存率明显低于中间型和成熟型CRC患者(P<0.05)。结论CD66b^(+)TANs和肿瘤间质DR程度均可影响CRC的临床生物学行为,评估CRC中CD66b^(+)TANs和DR有助于预测CRC患者的预后。

关键词：结直肠癌肿瘤相关中性粒细胞 CD66b 促纤维间质反应预后

房价波动对地方政府债务稳定性的影响——基于隐性担保和支出效率的分析

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金融研究 2024年第6期 60-77页

作者：王劲松唐洛秋黄佳祥武文慧韩向宇杭州师范大学经济学院浙江杭州311121 上海财经大学金融学院上海200433 南京银行杭州未来科技城支行浙江杭州311121

地方政府债务风险是当前我国重大金融风险之一,防范化解地方政府债务风险,是实现高质量发展和中国式现代化的必然要求。本文通过构建动态随机一般均衡模型,并将隐性担保纳入模型,在地方政府不同支出效率下,量化研究房价波动对地方债务... 详细信息

地方政府债务风险是当前我国重大金融风险之一,防范化解地方政府债务风险,是实现高质量发展和中国式现代化的必然要求。本文通过构建动态随机一般均衡模型,并将隐性担保纳入模型,在地方政府不同支出效率下,量化研究房价波动对地方债务稳定性的影响。本文发现,土地财政是房价波动影响地方政府债务稳定性的关键体制性因素;隐性担保和地方政府支出低效,均会加剧房价波动对地方政府债务稳定性的影响;政府支出效率提高,能显著削弱“房价—地方债”反馈机制。为维护地方政府债务稳定,必须遏制地方政府土地融资行为和对国有企业隐性担保,并切实提高地方政府支出效率。

关键词：房价波动地方政府债务稳定性动态随机一般均衡模型

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基于RSM的GFRC配合比设计优化

混凝土 2024年第8期 179-183,192页

作者：李良平唐伟桐甘元初王劲松黄瑶南华大学土木工程学院湖南衡阳421001 南华大学长三角(诸暨)研究院浙江绍兴312000

为了探究玻璃纤维掺量、玻璃纤维长度和陶粒对混凝土力学性能的影响,配制玻璃纤维增强混凝土(GFRC),采用响应面法和中心复合表面设计探究单因素间交互作用对GFRC性能的影响。结果表明:单因素对混凝土抗压强度响应显著程度依次为陶粒取代... 详细信息

为了探究玻璃纤维掺量、玻璃纤维长度和陶粒对混凝土力学性能的影响,配制玻璃纤维增强混凝土(GFRC),采用响应面法和中心复合表面设计探究单因素间交互作用对GFRC性能的影响。结果表明:单因素对混凝土抗压强度响应显著程度依次为陶粒取代率>玻璃纤维掺量>玻璃纤维长度,双因素交互作用下显著程度为玻璃纤维长度和玻璃纤维掺量>陶粒取代率和玻璃纤维掺量>陶粒取代率和玻璃纤维长度;GFRC最优配合比组合为陶粒取代率为10.6%,玻璃纤维长度为14.4 mm,玻璃纤维掺量为0.59%时,预测抗压强度最高为48.5 MPa,与实测平均值相差仅0.2 MPa。该成果有助于GRFC的推广使用,也为此提供了优化配合比设计和参考试验数据,具有工程指导意义。

关键词：混凝土玻璃纤维响应曲面法轻骨料力学性能

Building Load Forecasting Using Deep Neural Network with Efficient Feature Fusion

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Journal of Modern Power Systems and Clean Energy 2021年第1期9卷 160-169页

作者： jinsong wang Xuhui Chen Fan Zhang Fangxi Chen Yi Xin the Department of Electrical Computerand System Engineering at Case Western Reserve UniversityClevelandUSA the College of Aeronautics and Engineering Kent State UniversityKentUSA Northeastern University.Shenyang China

The energy consumption of buildings has risen steadily in recent years. It is vital for the managers and owners of the building to manage the electric energy demand of the buildings. Forecasting electric energy consumption of the buildings will bring great profits, which is influenced by many factors that make it very difficult to provide an advanced forecasting. Recently, deep learning techniques are widely adopted to solve this problem. Deep neural network offers an excellent capability in handling complex non-linear relationships and competence in exploring regular patterns and uncertainties of consumption behaviors at the building level. In this paper, we propose a deep convolutional neural network based on Res Net for hour-ahead building load forecasting. In addition, we design a branch that integrates the temperature per hour into the forecasting branch. To enhance the learning capability of the model, an innovative feature fusion is presented. At last, sufficient ablation studies are conducted on the point forecasting, probabilistic forecasting, fusion method, and computation *** results show that the proposed model has the state-of-theart performance, which reflects a promising prospect in application of the electricity market.

关键词： Load forecasting deep learning convolutional neural network feature fusion Res Net

长期不同施肥和深翻对玉米高粱轮作体系作物钾利用及土壤钾形态的影响

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中国农业科学 2024年第12期57卷 2390-2403页

作者：杨文辉罗灏程董二伟王劲松王媛刘秋霞黄晓磊焦晓燕山西农业大学资源环境学院/农业农村部有机旱作农业重点实验室

【目的】研究长期施用化肥钾、秸秆还田、有机肥配施化肥钾结合秸秆还田及其深翻对玉米高粱轮作体系作物钾利用效率、土壤钾形态及非交换性钾释放的影响，为合理使用钾肥和提高钾养分资源高效利用提供理论依据。【方法】于2011—2022年... 详细信息

【目的】研究长期施用化肥钾、秸秆还田、有机肥配施化肥钾结合秸秆还田及其深翻对玉米高粱轮作体系作物钾利用效率、土壤钾形态及非交换性钾释放的影响，为合理使用钾肥和提高钾养分资源高效利用提供理论依据。【方法】于2011—2022年在山西省晋中市进行长期定位试验，共设6个处理：不施肥（CK）、氮磷肥（NP）、氮磷钾肥（NPK）、秸秆还田结合有机肥（MS）、氮磷钾肥配施有机肥结合秸秆还田（NPKMS）、氮磷钾肥配施有机肥结合秸秆还田和深翻（NPKMSD），研究不同施肥处理对作物籽粒产量、地上部钾吸收量、钾利用效率、土壤钾形态和土壤非交换性钾释放特征的影响。【结果】与NP和NPK比较，MS、NPKMS和NPKMSD提高籽粒产量6%—8%，地上部钾吸收量提高22%—43%。NPKMS和NPKMSD处理钾素农学利用效率仅为NPK和MS的50%；施肥改变了土壤剖面钾形态，2022年收获后与CK、NP和NPK处理相比，MS、NPKMS和NPKMSD处理0—20 cm土层速效钾含量分别提高了2.2—2.8倍，缓效钾提高了8%—10%；与NPKMS比较，NPKMSD提高了20—40 cm土层速效钾含量。基于随机森林回归模型分析表明，0—20和20—40 cm土层的速效钾与缓效钾含量能解释地上部钾吸收量的64.1%,0—20 cm土层速效钾、缓效钾含量和20—40 cm土层的速效钾含量是影响植株钾吸收的关键因子。用氯化钙浸提时NPK、MS、NPKMS和NPKMSD处理0—20 cm土层非交换性钾累积释放量分别是NP的1.04、1.77、1.99和1.81倍，柠檬酸浸提时则分别为1.05、1.41、1.85和1.63倍。与NPKMS处理比较，NPKMSD处理20—40 cm土层柠檬酸浸提的非交换性钾累积释放量提高17.8%，而氯化钙浸提对其非交换性钾累积释放量没有显著影响。【结论】与施用相当量的化肥钾比较，秸秆还田和有机肥能明显活化土壤钾，提高土壤有效钾和缓效钾的含量，提高钾肥利用效率。化肥钾配施有机肥结合秸秆还田会造成作物钾奢侈吸收降低钾利用效率。深翻提高根层下土层速效钾含量但对产量影响不显著。秸秆还田和有机肥明显促进土壤非交换性钾的释放速率和累积释放量，长期秸秆还田结合适量有机肥能够替代化学钾肥。

关键词：长期施肥深翻土壤钾平衡土壤钾形态非交换性钾释放玉米高粱轮作秸秆还田有机肥

Numerical study of threshold gain behavior for a THz random laser in a two-dimensional active disordered medium with a three-level atomic system

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Chinese Science Bulletin 2011年第25期56卷 2664-2667页

作者： LIU Yong LIU jinsong wang KeJia Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Science and Tech-nology Wuhan 430074 China

By numerically solving Maxwell's equations and rate equations in a two-dimensional (2D) active random media made of ruby grains with a three-level atomic system, the threshold gain behavior for a THz random laser is investigated. The spectral intensity variation with the pumping rate is calculated for both the transverse magnetic (TM) field and the transverse electric (TE) field. The computed results show that THz random lasing could occur in a 2D disordered medium for both the TM and TE cases. Further analysis reveals that the THz lasing threshold for TM fields is lower than that for TE fields.

关键词：三能级原子系统激光阈值无序介质随机介质太赫兹数值研究行为增益

Voltage Breakdown of Ag Thin Film Deposited on Fractal Surface

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Chinese Physics Letters 1994年第1期11卷 43-45页

作者： wang jinsong YE Gaoxiang XU Yuqing ZHANG Qirui Department of Physics Zhejiang UniversityHangzhou 310027 Department of Physics Hangzhou UniversityHangzhou 310028

A new type of inhomogeneous system was constructed by depositing Ag thin films on fractal *** I-V characteristics of such samples exhibit a non-linear effect in air and a voltage breakdown effect in *** on the special structure geometry of the samples,these unusual phenomena can be explained by the random tunnelling junction model under different environment.

关键词： breakdown Fractal effect

Selection of cost-effective magnesium sources for fluidized struvite crystallization

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Journal of Environmental Sciences 2018年第8期30卷 144-153页

作者： jinsong wang Xin Ye Zhaoji Zhang Zhi-Long Ye Shaohua Chen Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Struvite crystallization has been considered a promising approach to recover phosphorus from wastewater. However, its practical application is limited, probably because of the high cost of magnesium（Mg）. In this study, a comprehensive economic analysis was conducted using five Mg sources（MgCl2, MgSO4, MgO, Mg（OH）2, and bittern） during the operation of a pilot-scale fluidized bed reactor（FBR）, using swine wastewater as the case matrix. First, the economic operating conditions were investigated, and subsequently, the performance and the costs of the five Mg sources were compared. The results indicated that the FBR could be operated most economically at pH of 8.5 and Mg to phosphorus（Mg/P） molar ratio of 1.5. Under these conditions, no significant differences in phosphorus removal and product quality could be found between the five Mg sources. Selecting the most economical Mg source was thus highly dependent on the prices of the reagents and Mg sources. Low-solubility Mg sources were preferable when NaOH was priced higher, while high-solubility Mg sources proved more economical when HNO3 was expensive. The bittern was the most economical choice only when the distances for total inorganic orthophosphate removal and struvite recovery were shorter than 40 and 270 km, respectively. The current study provides an overview of the economic selection of an Mg source, which can help reduce the cost of struvite crystallization.

关键词： Struvite Fluidized bed reactor Magnesium source Economy Phosphorus recovery