Passive IoT Localization Technology Based on SD-PDOA in NLOS and Multi-Path Environments

Addressing the challenges of passive Radio Frequency Identification(RFID)indoor localization technology in Non-Line-of-Sight(NLoS)and multipath environments,this paper presents an innovative approach by introducing a combined technology integrating an improved Kalman Filter with Space Domain Phase Difference of Arrival(SD-PDOA)and Received Signal Strength Indicator(RSSI).This methodology utilizes the distinct channel characteristics in multipath and NLoS contexts to effectively filter out interference and accurately extract localization information,thereby facilitating high precision and stability in passive RFID localization.The efficacy of this approach is demonstrated through detailed simulations and empirical tests conducted on a custom-built experimental platform consisting of passive RFID tags and an R420 reader.The findings are significant:in NLoS conditions,the four-antenna localization system achieved a notable localization accuracy of 0.25 m at a distance of 5 m.In complex multipath environments,this system achieved a localization accuracy of approximately 0.5 m at a distance of 5 m.When compared to conventional passive localization methods,our proposed solution exhibits a substantial improvement in indoor localization accuracy under NLoS and multipath conditions.This research provides a robust and effective technical solution for high-precision passive indoor localization in the Internet of Things(IoT)system,marking a significant advancement in the field.

Application Progress of Nanofiltration Combination Technology in the Treatment of Landfill Leachate

Under the impetus of environmental protection policies,the discharge requirements for leachate are becoming more and more stringent.Therefore,the treatment technology of landfill leachate has become a hot research topic at present.In this paper,the chemical composition and water quality characteristics of landfill leachate were briefly introduced,and the characteristics and performance of nanofiltration technology were summarized at first.Afterwards,the recent advances in the application of nanofiltration combination technology in the treatment of landfill leachate at home and abroad were summarized,and the research and application of the combination of membrane separation,chemical coagulation,chemical oxidation and adsorption methods with nanofiltration membrane in the treatment of landfill leachate were mainly introduced.Finally,it is proposed that the combination of nanofiltration technology is feasible and economical,and its reasonable selection and optimization are the directions of future research and have good application prospects.

Mechanical properties and damage characteristics of solidified body-coal combination in continuous driving and gangue backfilling

Recovery of the coal buried under buildings,railways and water bodies and the residual coal in irregularly arranged fully mechanized mining faces is a common engineering problem facing underground coal mining.In this study,a mining technology of continuous driving and gangue backfilling(CDGB)was proposed.The technology,which can not only alleviate ground subsidence and gangue discharge,but also release the above-mentioned coals,contributes to green and efficient sustainable development of mining.The stability of the system of the solidified body-reserved coal pillar combination(S-C combination)is crucial to the CDGB technology.Therefore,it is of great significance to explore the mechanical and damage characteristics of S-C combination in the synergistic bearing process.First,four sets of differentshaped S-C combination specimens were fabricated and a S-C combination bearing structure in CDGB was constructed to explore the differences in mechanical characteristics and damage modes of different-shaped S-C combination specimens during CDGB.Subsequently,their surface strain field evolutions and acoustic emission(AE)response characteristics in the load-bearing process were obtained with the aid of the digital image correlation technique and the AE signal monitoring system.Furthermore,a damage evolution model based on AE parameters and mechanical parameters was established to clarify the damage evolution law.The following results were obtained:(1)The free area of S-C combination can serve as a quantitative index to evaluate the stability of the overburden control system;(2)The concept of critical value k of the free area was first proposed.When the free area exceeds the critical value k(free area ratio greater than 1.13),the deformation resistance and the free area changes becomes negatively correlated;(3)As the free area expands,the failure of the S-C combination specimen evolves from tensile failure to shear failure.The distribution characteristics of the axial strain field also verified such a change in the failure mode;(4)When the free area expands,the peak AE count gradually changes from“double peaks”to“a single peak”.In this process,the expansion of free area shortens the time for accumulating and releasing energy during loading.Micro cracks generated in the specimen change from a phased steep growth to a continuous increase,and the process in which micro cracks develop,converge,intersect and connect to form macro cracks accelerates.The damage evolution law concluded based on AE parameters and mechanical parameters can well characterize the damage evolution process of S-C combination,providing certain reference for the study on the synergistic bearing of S-C combination during CDGB.

Research on Combined Construction Technology for Cross-Subway Tunnels in Underground Spaces

Given the increasingly notable segmentation of underground space by existing subway tunnels, it is dif- ficult to effectively and adequately develop and utilize underground space in busy parts of a city. This study presents a combined construction technology that has been developed for use in underground spaces; it includes a deformation buffer layer, a special grouting technique, jump excavation by compart- ment, back-pressure portal frame technology, a reinforcement technique, and the technology of a steel portioning drum or plate. These technologies have been successfully used in practical engineering. The combined construction technology presented in this paper provides a new method of solving key techni- cal problems in underground spaces in effectively used cross-subway tunnels. As this technology has achieved significant economic and social benefits, it has valuable future applications.

Reliability Theory Study of Combined Mining Technology System in Surface Mines

The connection between all the single systems iu combined technology is analysed, and the mine engineering reliability is calculated in any area of the mines using combined technololgy system. The reliability design and distribution method in this system is put forward, thus the basis is set for the decision to raise the total production capability or the surface mines in which the combined system is used.

Remediation Technology for Combined Pollution of Lead and Cadmium in Farmland Soil

At present,the problem of heavy metal pollution in farmland in southern China is serious. Especially,the cadmium and lead are two heavy metal elements with serious pollution and great harm to human body. This paper reviewed some common methods and materials used in the control of cadmium and lead pollution in farmland soil. Then,it discussed the problems in the repair of cadmium and lead pollution in farmland soil. It came up with the future research direction,to provide references for remediation of lead and cadmium pollution in farmland soil.

Development of Combined Biological Technology for Treatment of High-strength Organic Wastewater and Results of Case Studies

Our study group has developed a unique combined ters from the industries of dyestuff, pharmaceutical, chemical biological technology to treat high-strength organic wastewaengineering and zymolysis by using the principles of anaerobic ecological niche and bio-phase separation. The study obtained five national invention patents and eight patent equipments. This technology contains four kernel processes - two-phase anaerobic-aerobic process, hydrolysis-acidification-oxidation process, UASBAF-oxidation process, and internal cycling-hydrolysis-oxidation process. Fifteen pilot projects were accomplished in the basins of Tai Lake, Huai River, Liao River and Songhua River, and their total capital investment reached 185.214 million Yuan （RMB）. Compared to conventional wastewater treatment technology, the innovative technology is more costeffective for high-strength organic wastewater treatment, can save capital investment by 15% - 30%, lessen land usage by 20% to 40% and decrease the operating cost by 10% to 25%. The operating cost of treatment per cubic meter industrial wastewater could be below 0.6 to 1.4 Yuan （RMB）.

Application of high-pressure water jet technology and the theory of rock burst control in roadway

This paper puts forward using high-pressure water jet technology to control rock burst in roadway, and analyzes the theory of controlling rock burst in roadway by the weak structure zone model. The weak structure zone is formed by using high-pressure water jet to cut the coal wall in a continuous and rotational way. In order to study the influence law of weak structure zone in surrounding rock, this paper numerically analyzed the influence law of weak structure zone, and the disturbance law of coal wall and floor under dynamic and static combined load. The results show that when the distance between high-pressure water jet drillings is 3 m and the diameter of drilling is 300 mm, continuous stress superposition zone can be formed. The weak structure zone can transfer and reduce the concentrated static load in surrounding rock, and then form distressed zone. The longer the high-pressure water jet drilling is, the larger the distressed zone is. The stress change and displacement change of non-distressed zone in coal wall and floor are significantly greater than that of distressed zone under dynamic and static combined load. And it shows that the distressed zone can effectively control rock burst in roadway under dynamic and static combined load. High-pressure water jet technology was applied in the haulage gate of 250203 working face in Yanbei Coal Mine, and had gained good effect. The study conclusions provide theoretical foundation and a new guidance for controlling rock burst in roadway.

Flexibility of MIP Technology

The flexibility of MIP technology to meet market demand is mainly introduced in this study. Their commercial application and technical principle are analyzed too. The MIP technology with wide feed adaptability can form a good combination with other technologies. The MIP technology has been applied extensively in China. Based on this platform, the CGP, MIP-LTG and MIP-DCR technologies have been developed, which can further improve the flexibility of MIP technology. Based on its novel reaction control technique with a sole sequential two-zone riser, the MIP users can easily switch to different operating modes between producing either more clean gasoline and propylene or diesel through changing the catalysts and varying the operating conditions. That offers MIP users with enough production flexibility and a rational production arrangement to meet the market demand. The MIP-DCR technology with less dry gas and coke yields can provide a more flexible operating mode since the catalysts to oil ratio has become an independent variable.

Propagation properties of off-axis Hermite-cosh-Gaussian beam combinations through a first-order optical system

Based on the Collins integral formula, the analytic expressions of propagation of the coherent and the incoherent off-axis Hermite-cosh-Gaussian （HChG） beam combinations with rectangular symmetry passing through a paraxial first-order optical system are derived, and corresponding numerical examples are given and analysed. The resulting beam quality is discussed in terms of power in the bucket （PIB）. The study suggests that the resulting beam cannot keep the initial intensity shape during the propagation and the beam quality for coherent mode is not always better than that for incoherent mode. Reviewing the numerical simulations of Gaussian, Hermite-Gaussian （HG） and cosh- Gaussian （ChG） beam combinations indicates that the Hermite polynomial exerts a chief influence on the irradiance profile of composite beam and far field power concentration.

Research on Technology of Pressure Pretreatment with Oxygen for Refractory Gold Ores

An combined technology of pressure pretreatment with oxygen on refractory gold ores is pointed out and discussed on this paper, according to the experiments included the test in 1 kg grade batch pressure pretreatment with oxygen of the concentrate from the refractory gold ores of Dongbeizhai in Sichuan province, which is called the most refractory gold ores in China. It is shown that gold recovery reach 91.73% in the combined process which is described as follows: The flotation of the sulphide gold ores is under controlled conditions, producing the concentrate for pressure pretreatment with oxygen in acidic medium and the middling for the pressure pretreatment with oxygen in alkaline medium. The thickening and washing process substitute the pressure filtration process of the pulp after pressure pretreatment. The thick slimes of the two kinds of pressure pretreatment were mixed and then enter the CIL process for simplifying the flowsheet. The possible superabundance of acid of pressure pretreatment with oxygen in acidic medium was neutralized by the tailings of flotation and the cost of neutralization will be lower. The combined technology of pressure pretreatment with oxygen has the same advantages as the normal technology of pressure pretreatment and both is helpful for environment protection.

Application of Multimedia Technology in Feature Wall Design

New value systems and new aesthetic experience have been formed in the new era,triggered by reform of technical means and transformation of social economy. New multimedia technologies will produce new feelings,new experience and new ways of thinking,which correspondingly result in changes of landscape designs. Virtual reality technology is used to build autokinetic effect and mobility of feature wall,complex structures and forms,vivid and creative landscape elements,so that the landscapes will interact with users intimately,and humanized landscape spaces will be created.

Off-design Characteristics of IGCC System Based on Two-stage Coal-slurry Gasification Technology

整体煤气化联合循环（integrated gasification combinedcycle,IGCC）机组在一定情况下处于非设计工况运行。为了研究IGCC系统变工况特性,采用ThermoFlex软件建立基于两段式水煤浆气化技术的200 MW级整体煤气化联合循环系统模型,主要考查燃气轮机负荷、整体空分系数Xas、大气温度、大气压力对系统性能的影响。研究结果表明,降低燃气轮机负荷或者提高大气温度系统效率均呈先升高而后降低的趋势。整体空分系数Xas增加,机组发电效率降低。大气压力对系统效率影响较小。上述条件下采用两段水煤浆气化技术,系统性能可以得到有效改善。研究结果可为采用两段式水煤浆气化技术的IGCC系统的设计、运行提供参考。

光催化氧化技术处理废水中抗生素的研究进展

本文综述了光催化氧化技术处理废水中抗生素污染物的研究现状,主要介绍了半导体光催化剂、光催化复合膜及一些与光催化氧化技术相关的联合技术在废水抗生素污染物处理领域的应用进展,同时详细地介绍了各种方法对抗生素污染物的处理效果及其优缺点。最后,展望了光催化氧化技术在废水中抗生素污染物处理领域未来的研究重点和发展趋势。

新疆油田浅层超稠油SAGD高效低碳开发技术研究与展望

针对“双碳”目标背景下超稠油开发高能耗与油田高质量发展矛盾日益加剧的问题,新疆油田通过SAGD机理研究与现场实践,在维持蒸汽腔高效扩展,突破储层渗流屏障遮挡,提高浅薄层驱泄复合效率,实现水平井长水平段高效均衡产液等方面持续攻关,取得显著效果。采用气体辅助技术,实现蒸汽腔隔热保压增能,油汽比可提高20%;利用立体井网及储层升级扩容技术,改善Ⅲ类超稠油油藏渗流特征,泄油速度可增大20%~40%;采用全密闭生产方式,VHSD产液温度由100℃上升至150℃,采油速度提高50%;深化热采流量控制器(FCD)机理研究,完善油藏-井筒耦合优化设计方法,水平井水平段动用程度可提高20%。“十四五”期间,新疆油田将深化溶剂辅助SAGD、无水SAGD和控温水热裂解等技术研究,逐步完善浅层超稠油低碳高效开发技术系列,该研究可为稠油油藏开发提供借鉴。

超声-紫外(US-UVC)联用绿色科学养护当归

目的采用超声净洗和短波紫外(UVC)消毒技术联用绿色科学养护中药材当归,通过定期观测,分时段取样测定各中国药典指标,同时UVC消毒再养护,根据结果评价养护效果并分析优化确定超声-紫外(US-UVC)联用养护当归药材的最佳条件.方法以纯净水清洗当归(CG-W)和超声净洗当归(CG-US)作为对照组,将当归超声净洗后干燥直至足干,再利用UVC照射消毒至设定的时间,通过定期肉眼观测和分时段测定各种药典指标及其变化,综合评价养护效果.结果CG-W对照组当归18月后仍无霉变但有极其轻微的虫蛀,到24月时出现了略微的霉变,似有轻微色变和隐约渗油,历时27月时出现可见且明显的虫蛀;对照组CG-US当归21月末出现轻微虫蛀,24月时虫蛀仍然较轻,且无明显霉变和色变;US-UVC联用养护组中US-UVC-0.5h组在27月末出现了轻微药材粉末,且在27~30月间仅有部分药材出现虫蛀,且一直没有霉变和色变,颜色无明显变化,而US-UV-1.0h组的当归在贮藏至30月末时出现了极轻虫蛀迹象.US-UV-2.0h、US-UV-3.0h和US-UV-4.0h各组当归在养护后贮藏期间的30月内始终保持表观完好无损的状态,既无虫蛀也无霉变、色变现象发生.对照组及试验各组各时段所测定的各种主要药典指标均符合要求,且由测定结果的相对标准偏差(RSD)值及其范围足以说明测定方法的重复性和稳定性良好.结论考虑成本和养护时效,以US-UVC-2.0h养护为最佳养护配比组合进行养护,养护后当归药材完好贮藏期超过30月,US-UVC联用养护中药材当归具有经济高效、操作简便、省时节能、安全环保等特点,可以推广应用.

基于“虚拟现实+”的数字媒体技术探索

随着互联网技术的发展,数字媒体技术已广泛应用于各行业。基于“虚拟现实+”的数字媒体技术能够创设全新的仿真情境,为用户提供更加真实的视觉以及听觉体验,对智能化发展有着显著的推动作用。文章介绍了“虚拟现实+”技术及数字媒体技术的应用现状,并从二者的交互性、多感知性、构想性等方面探究了基于“虚拟现实+”的数字媒体技术用户体验,以期为相关从业人员提供参考。

基于One NET云平台和北斗GPS双模定位的智慧停车系统

本文指出目前智慧停车面临三大技术难题:一是如何实现高精度停车位置定位;二是如何准确实现车位空闲状态检测;三是构建互联互通的停车场停车信息网络系统并对接到云平台,实现整个城市停车信息的大数据共享。为此,本文设计了一款基于OneNET云平台和北斗GPS双模定位的智慧停车系统,从理论上可解决上述3个关键问题。系统经过测试运行正常,数据收发正常,各传感器和北斗GPS定位数据准确,云平台数据更新保持在1~2 s之间。表明该系统具有车位状态监测准确、位置定位可精确到分米级别、数据上传到云平台存储和显示快速及时的特点,能够提高停车场的利用率和周转率,方便车主出行和生活。

个体化3D打印技术联合心理干预在下肢创伤骨折手术患者中的应用效果

目的:探讨基于医工结合背景下个体化3D打印技术联合心理干预,在改善下肢创伤骨折手术患者情绪状态的影响效果。方法:选取在唐山市第二医院住院治疗的下肢创伤性骨折手术患者为研究对象。将2022年1-6月住院的患者45例作为对照组,采用传统常规方式进行健康宣教;选取2022年7-12月住院的患者47例为研究组,采用医工结合背景下3D打印技术联合心理干预进行干预,比较两组患者入院时和出院时的焦虑自评量表(SAS)评分和抑郁自评量表(SDS)评分差异,比较两组患者存在焦虑状态和抑郁状态差异,比较两组患者依从性(包括健康教育掌握情况、配合治疗护理)和对护理工作满意度的差异。结果:①两组患者入院时焦虑和抑郁情绪没有显著差异,但在出院时研究组的SAS评分和SDS评分与对照组有显著差异(F=111.216,54.172;P<0.01),且实验组的焦虑和抑郁显著低于对照组,差异具有统计学意义(P<0.05);②两组患者的依从性和满意度存在显著性差异,差异均具有统计学意义(χ^(2)=5.520,7.723;P<0.05)。结论:医工结合背景下之3D打印技术联合心理干预可有效减轻下肢创伤骨折患者的焦虑、抑郁情绪,提升患者的依从性和满意度。

解析建筑设计中绿色建筑技术优化结合

随着社会经济的快速发展,城市建设步伐加快,建筑行业在推动经济发展的同时,也带来了诸多环境问题。绿色建筑作为一种可持续发展的建筑理念,逐渐成为当今建筑设计的重要方向。本文将分析建筑设计中绿色建筑技术的优化结合,以期为建筑行业的可持续发展提供参考。