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China Communications 2025年第1期22卷 111-127页

作者： Jiang wangjun Wei Zhiqing Feng Zhiyong Chen Xu Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on *** can detect the targets on the road with communication signals using the integrated sensing and communication(ISAC)*** with vehicle-mounted radar,SBS has a better sensing field due to its higher deployment position,which can help solve the problem of sensing blind *** this paper,key technologies of SBS are studied,including the beamforming algorithm,beam scanning scheme,and interference cancellation *** transmit and receive ISAC signals simultaneously,a double-coupling antenna array is *** free detection beam and directional communication beam are proposed for joint communication and sensing to meet the requirements of beamwidth and pointing *** joint timespace-frequency domain division multiple access algorithm is proposed to cancel the interference of SBS,including multiuser interference and duplex interference between sensing and ***,the sensing and communication performance of SBS under the industrial scientific medical power limitation is analyzed and *** results show that the communication rate of SBS can reach over 100 Mbps and the range of sensing and communication can reach about 500 m.

关键词： beamforming integrated sensing and communication(ISAC) interference cancellation performance analysis sensing base station

数智技术赋能体育用品制造业数字化转型的作用机制与推进路径

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天津体育学院学报 2025年第1期40卷 86-93页

作者：师浩轩柴王军西安体育学院运动训练学院陕西西安710068

数字化转型是数字经济时代体育用品制造业实现高质量发展的必然要求,数智技术正成为赋能体育用品制造业数字化转型的重要动能。数智技术赋能体育用品制造业数字化转型,是将数智技术应用于体育用品制造业的管理模式、设计研发、生产制造... 详细信息

数字化转型是数字经济时代体育用品制造业实现高质量发展的必然要求,数智技术正成为赋能体育用品制造业数字化转型的重要动能。数智技术赋能体育用品制造业数字化转型,是将数智技术应用于体育用品制造业的管理模式、设计研发、生产制造、营销售后环节中赋能体育用品制造业高效配置资源要素、优化业务管理模式、提升服务质量,全面推动体育用品制造业高质量发展所进行的一种全价值链的增值活动。数智技术赋能体育用品制造业数字化转型的作用机制体现在赋能管理模式从“传统组织”向“弹性组织”转变,设计研发从“预测市场”向“满足需求”转变,生产制造从“人智驱动”向“数智驱动”转变,营销及售后服务从“产品中心”向“客户中心”转变。数智技术赋能体育用品制造业数字化转型的现实实践体现在数智技术赋能体育用品制造业零售模式变革、供应链优化、智能制造升级和消费体验创新。应健全体育用品制造业数字转型的政策体系、强化体育用品制造业数字化转型的数字创新驱动、建立体育用品制造业“生产—消费”数字生态化链接、创新体育用品制造业数字化转型的人才培养方式等推进路径。

关键词：数智技术数字化转型体育用品制造业

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基于机器学习筛选猪活体肌内脂肪含量间接选育和构建预测模型的关键性状

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南京农业大学学报 2025年第1期48卷 161-170页

作者：吴建杨文孟孜查成万吴望军南京农业大学动物科技学院江苏南京210095

[目的]本研究旨在探究猪断奶重、屠宰前活体重、背膘厚等性状因素对猪肌内脂肪(intramuscular fat,IMF)含量的影响,确定影响猪IMF含量的关键性状因素。[方法]以805头皮特兰×[杜洛克×(长白×大白)]四元商品猪群为试验对象,记录性别,测... 详细信息

[目的]本研究旨在探究猪断奶重、屠宰前活体重、背膘厚等性状因素对猪肌内脂肪(intramuscular fat,IMF)含量的影响,确定影响猪IMF含量的关键性状因素。[方法]以805头皮特兰×[杜洛克×(长白×大白)]四元商品猪群为试验对象,记录性别,测定初生重、断奶重、屠宰前活体重和IMF含量等14个性状,然后通过相关性分析从14个性状中初步筛选出影响IMF含量的性状因素,再通过随机森林模型评估各性状因素对IMF含量影响的重要性,进一步通过LASSO回归和逐步回归筛选出影响IMF含量的关键性状因素;在此基础上,利用广义线性模型(generalized linear model,GLM)分析关键性状因素不同水平对IMF含量的影响。[结果]相关性分析结果显示,猪IMF含量与断奶重(r=0.13, P0.05)。胸腰椎结合处背膘厚大于26 mm组的平均IMF含量(2.73%)显著高于其他背膘厚组(P0.05)。[结论]本研究通过机器学习确定了性别、断奶重、屠宰前活体重和胸腰椎结合处背膘厚4个与IMF含量显著相关的活体可测定性状,并发现平均IMF含量随着屠宰前活体重和胸腰椎结合处背膘厚的增加呈明显的上升趋势。

关键词：猪肌内脂肪间接选择模型构建机器学习活体可测定性状

The First Observation of Circumstellar Nebula of VI Cyg 12

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Chinese Physics Letters 2003年第5期20卷 778-779页

作者： wangjun-Jie ZHUZhen-Xi NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 PurpleMountainObservatory ChineseAcademyofSciencesNanjing210008

An optical spectroscopic observation was made towards the circumstellar nebula of the supergiant VI Cyg 12, for the first time to the best of our knowledge. Several emission lines appear in the spectrum. Based on the spectra of the star and its circumstellar matter, as well as the IRAS and NVSS data, we conclude that VI Cyg 12 has an expanding shell with an expansion velocity 3100 km s-1 due to strong stellar wind. It is an older star that possibly evolved from a very massive O-type star. The stellar wind and mass loss may take an important part in the evolution of this star.

关键词：恒星星云光谱天文观测光学分光镜

SIMULATION AND EXPERIMENTATION OF THE ARC WELDING INVERTER USING THE SOFT SWITCHING TECHNIQUE

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Chinese Journal of Mechanical Engineering 2004年第1期17卷 82-84页

作者： ChenShujun wangjun HuangPengfei CollegeofMechanicalEngineenng＆AppliedElectronicsTechnology BeijingUniversityofTechnologyBeijing100022China CollegeofMatenalScienceandEngineeringHebeiUniversityofScienceandTechnology Shijiazhuang050054China CollegeofMechanicalEngineering＆AppliedElectronicsTechnology BeijingUniversityofTechnologyBeijing100022China

The FB-ZVZCS-PWM converter is realized by the way of subjoiningblock-capacitor into the FB-ZVS-PWM converter. At the freewheeling interval, the primary current isattenuated fast to zero and maintained. And then, power device of the static leg becomes azero-current-switch (ZCS), power device of the shifted leg becomes a zero-voltage-switch(ZVS). Thus,on one hand IGBT (Insulated gate bipolar transistor) with tail current can be easily used infull-bridge soft-switching converter; on the other hand additional circuiting energy is greatlyreduced. At the same time, less duty cycle loss, lower secondary parasitic resonance, widersoft-switching load range can be achieved. Based on the existing component models in the Pspicesoftware package, a combined model of IGBT is established, in which a non-linear capacitor isintroduced to replace the parasitic capacitor. Using this model, computerized simulation isconducted for the FB-ZVZCS-PWM soft-switching converter, the switching and energy-transferringcharacteristics of the power device are analyzed. Finally, based on the achievement above, a 10 kWarc welding inverter with FB-ZVZCS-PWM converter is developed. The simulation results are testifiedby experiments. It is proved that by adopting appropriate models, computerized simulation is aneffective and useful tool for the development of the arc welding inverter.

关键词： Arc welding inverter Soft switching Zero-voltage-switching(ZVS) Zero-currentswitc-hing(ZCS)

Development of Search System Used for Material Processing by Mobile Internet

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Journal of Iron and Steel Research International 2004年第3期11卷 33-36页

作者： wangjun ZHANGLi FANLei NortheasternUniversity Shenyang110004China DalianUniversityofTechnology Dalian116024China PoliceStartionofHuanggu Shenyang110036China)

A wireless search system was integrated on Windows 2000 *** on the communication principle between wireless data and Internet,the object expression of search file,the automatic query of document information,the segment browsing of result information,and the receiving and sending of user information were realized by using Active Server Page 3.0,VB Script,WML Script insert languages and object orient database *** requirement querying information of material processing through Internet by GPRS,WAP mobile handset and so on was accomplished.

关键词： material processing information search dynamic refreshment mobile Internet

Genetic relationship between Neobenedenia girellae and N. melleni inferred from 28S rRNA sequences

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Acta Oceanologica Sinica 2004年第4期23卷 709-716页

作者： wangjun ZHANGWen SUYongquan DINGShaoxiong CollegeofOceanographyandEnvironmentalScience XiamenUniversityXiamen361005China

The fragments of 350 bp in 28S rRNA from the closely related monogenea of trematoda, Neobenedenia girellaeand N. melleni are obtained by polymerase chain reaction (PCR) amplified using a couple of special primers andthen sequenced. The results show that the comparison of 28S rRNA sequences, with only a base varying in 337bp accounting for 0.3% genetic difference, from the relative species N. girellae and N. melleni parasitized on thedifferent fishes in different farms displays that they possess a very high genetic similarity of 99.7%, higher thanthat of 99.41% for the single species N. melleni sampled in different areas, and the intraspecific divergence of *** is 0.59%. Meanwhile, the interspecific differences between the two Neobenedenia and three Benedenia (i.e., B. lutjani, B. rohdei and B. seriolae) range from 2.08% to11.73%. In addition, UPGMA and MP molecularphylogenetic trees are constructed and proved to be consistent with each other. Though the morphologicalcharacteristics and the results of genetic diversity for the two Neobenedenia show a high similarity, whether theybelong to a single species or not are still undefined, and the more genes of them should be further investigated, incombination with the systematical and detailed morphological study.

关键词： S rRNA Neobenedenia sequence analysis

The effects of land use and its patterns on soil properties in a small catchment of the Loess Plateau

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Journal of Environmental Sciences 2003年第2期15卷 263-266页

作者： wangjun FUBo－jie 等 LandConsolidationandRehabilitationCenter MinistryofLandandResourcesBeijing100035China DepartmentofSystemsEcology ResearchCenterforEco－EnvironmentalSciencesChineseAcademyofScienc

Due to relatively strong human activities in the hilly area of Loess Plateau, the natural vegetation has been destroyed, and landscape pattern based on agricultural land matrix was land use mosaic composing of shrub land, grassland, woodland and orchard. This pattern has an important effect on soil moisture and soil nutrients. The Danangou catchment, a typical small catchment, was selected to study the effects of land use and its patterns on soil moisture and nutrients in this paper. The results are as follows: The comparisons of soil moisture among seven land uses for wet year and dry year were performed: (1) the average of soil moisture content for whole catchment was 12.11% in wet year, while it was 9.37% in dry year; (2) soil moisture among seven land uses was significantly different in dry year, but not in wet year; (3) from wet year to dry year, the profile type of soil moisture changed from decreasing type to fluctuation-type and from fluctuant type to increasing type; (4) the increasing trend in soil moisture from the top to foot of hillslope occurred in simple land use along slope, while complicated distribution of soil moisture was observed in multiple land uses along slope. The relationships between soil nutrients and land uses and landscape positions were analysed: (1) five nutrient contents of soil organic matter (SOM), total N (TN), available N (AN), total P (TP) and available P (AP) in hilly area were lower than that in other areas. SOM content was less than 1%, TN content less than 0.07%, and TP content between 0.05% and 0.06%; (2) SOM and TN contents in woodland, shrub land and grassland were significantly higher than that in fallow land and cropland, and higher level in soil fertility was found in crop-fruit intercropping land among croplands; (3) soil nutrient distribution and responses to landscape positions were variable depending on slope and the location of land use types.

关键词： hilly area of Loess Plateau land use pattern soil moisture soil nutrient

Perihelion Precession,in Gravitational Field of Center Mass with Electric Charge and Magnetic Moment

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Communications in Theoretical Physics 2005年第5期43卷 806-808页

作者： wangjun WANGYong-Jiu InstituteofPhysics HunanNormalUniversityChangsha410081China

With a perfect mathematical method by us, we obtain some expressions of the orbital effect for a test particle and some meaningful results in the gravitational field of the center mass with electric charge and magneti... 详细信息

关键词： magnetic moment additional angle-movement

Topological Vortices in Superfluid Films

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Communications in Theoretical Physics 2005年第1X期44卷 160-164页

作者： wangjun-Ping DUANYi-Shi InstituteofTheoreticalPhysics LanzhouUniversityLanzhou730000China InstituteofScienceandTechnologyforOpto-electronicInformation YantaiUniversityYantai264005China

We study the topological structure of the vortex system in a superfiuid film. Explicit expressions for the vortex density and velocity field as functions of the superfluid order parameter are derived. The evolution of... 详细信息

关键词：拓扑旋涡超流体拓扑结构旋涡密度