MOVES模型在城市交通碳减排评估中的应用

为准确评估城市道路交叉口信号优化的碳减排效果,在实际交通调查的基础上利用MOVES模型模拟信号优化后道路车辆污染物排放的变化,对交通管控的节能减排效应进行定量分析。结果表明:信号优化不仅能有效缓解交通拥堵,提高主干道交通流的速度,还能够不同程度降低不同污染物的排放总量,尤其是CO_(2)的排放量;虽然信号优化后不同污染物排放总量都在降低,但对于道路行驶的基数较小的车型,其污染物排放趋势有可能增加;不同污染物对信号优化的敏感性不同,因此减排效果不同,但相同车型的不同污染物的减排趋势相似。通过详细分析模型参数的本地化过程和排放结果,所研究的污染物排放测算方法更符合实际情况,可以为其他城市交通管控的减排效益研究提供参考,为城市的低碳绿色发展提供理论基础。

"Five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in laparoscopic pancreaticoduodenectomy

BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require further clinical evaluation and investigation.AIM To explore the application value of the"five steps four quadrants"modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients.METHODS A total of 52 patients who underwent LPD via the"five steps four quadrants"modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively.The patients'body mass index(BMI),preoperative laboratory indices,intraoperative variables and postoperative complications were recorded.The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed.RESULTS Among the 52 patients,36 were males and 16 were females,and the average age was 62.2±11.0 years.There were 26 patients with pancreatic head cancer,16 patients with periampullary cancer,and 10 patients with distal bile duct cancer.The BMI was 22.3±3.3 kg/m²,and the median total bilirubin(TBIL)concentration was 57.7(16.0-155.7)µmol/L.All patients successfully underwent the"five steps four quadrants"modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage.Correlation analysis revealed significant associations between preoperative BMI(r=0.3581,P=0.0091),TBIL level(r=0.2988,P=0.0341),prothrombin time(r=0.3018,P=0.0297)and lymph node dissection time.Moreover,dissection time was significantly correlated with intraoperative blood loss(r=0.7744,P<0.0001).Further stratified analysis demonstrated that patients with a preoperative BMI≥21.9 kg/m²and a TIBL concentration≥57.7μmol/L had significantly longer lymph node dissection times(both P<0.05).CONCLUSION The"five steps four quadrants"modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD.This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve;thus,it is worthy of further clinical promotion and application.

Half-integer Shapiro steps in MgB_(2) focused He ion beam Josephson junctions

Half-integer microwave induced steps(Shapiro steps)have been observed in many different Josephson junction systems,which have attracted a lot of attention because they signify the deviation of current phase relation(CPR)and uncover many unconventional physical properties.In this article,we first report the discovery of half-integer Shapiro steps in MgB_(2)focused He ion beam(He-FIB)Josephson junctions.The half-integer steps'dependence on microwave frequency,temperature,microwave power,and magnetic field is also analyzed.We find that the existence of half-integer steps can be controlled by the magnetic field periodically,which is similar to that of high temperature superconductor(HTS)grain boundary junctions,and the similarity of the microstructures between gain boundary junctions and He-FIB junctions is discussed.As a consequence,we mainly attribute the physical origin of half-integer steps in MgB_(2)He-FIB junctions to the model that a He-FIB junction is analogous to a parallel junctions'array.Our results show that He-FIB technology is a promising platform for researching CPR in junctions made of different superconductors.

A Clean Switch Inner Mongolian town takes giant steps in transitioning to clean energy production

Staff at the Ruichen Wanniu Livestock Farm in Jungar Zhao Town,Jungar Banner,Inner Mongolia,are consistently busy,even during important festivals.

基于MOVES的高速公路客运交通排放特性研究

研究了高速公路客车污染物排放时空分布特性,为政府相关部门制定合理的交通管制措施提供理论支持,从而减轻客车排放对高速公路及周围环境造成的危害。以2021年云南省高速公路通行客车收费数据为基础,结合云南省客车技术特征、环境条件及燃油特性等参数对MOVES模型进行本土化修正,从而计算高速公路客车排放因子,结合车流量及行驶里程建立2021年云南省排放清单,并采取自下而上的方法和ArcGIS技术对排放清单进行时空分布分析。结果表明,各项污染物主要来源于客一。在时间分布上,在工作日期间客车污染物排放量在8时及18时左右出现双高峰结构,而非工作日期间,在14时到18时之间一直处于较高的排放水平;在空间分布上,污染物分布以昆明市为中心向四周扩散,离昆明市越远的地方,污染物排放分担率越小。

基于move-step模型的地铁车站站务通信言语特征分析

规范化的通信用语可以减少沟通双方的交流时间,使接收者获取到准确的信息内容。将地铁车站站务通信按内容分为日常运营信息及突发/紧急事件信息两类,并基于move-step模型将这两类信息分为3个沟通阶段及多个沟通步骤。根据地铁车站站务通信的特点,将其言语特征分为呼叫、指示、请求、声明、通知、回复及通话完毕7种类型,并列举了相应的标准化用语范例。

基于TeamSTEPPS理论的案例情景教学法在急诊护理团队培训中的应用

急诊科具有危重患者多,突发状况多,医疗风险高等特点,目前国内大多数医院急诊科护士以团队形式开展工作,但临床工作中易出现职责分工不明确、配合不协调、组织抢救混乱等问题^([1])。团队培训是增强团队优质高效协作的重要途径^([2]),为进一步提升急诊护理团队协作,保障患者安全,本次研究将前期基于提高医疗质量和患者安全的团队策略与工具(team strategies and tools to enhance performance and patient safety,TeamSTEPPS)理论构建的急诊护理团队培训方案^([3])进行临床应用,取得了较好的效果。现报道如下。

In Her Father's Footsteps

Chinese nurse chooses to join a medical mission to Mali, just like her father Hong Min will never forget 18 July 2017. It was the day when the nurse received the medal of the Order of Health Merit of Mali for her service in the country as part of the 24th Chinese medical team.The award, in the words of Samba Ousmane Sow, then minister of health and public hygiene.

Performance improvement in stepped solar still modified by sponge layer

In this paper,the experimental investigation on the performance improvement of conventional stepped solar still is conducted.The steps are covered by the porous material to improve the performance of the conventional device and increase the evaporation rate.All the parameters,including the temperature on the glass surface,the water temperature inside the evaporation zone,and the amount of water produced in both conventional and modified stepped solar stills are measured and compared.The efficiency of two devices and their exergy efficiency have been calculated.Finally,the economic analysis of both devices has been done to check the economic feasibility of the modified device.The amount of freshwater generated during one day was 2244.4 and 3076.2 mL/m^(2),respectively for the conventional and modified stepped solar stills.As a result,the amount of water produced in one day by modified stepped solar still is 35.5% more than the conventional one.Also,the costs for the conventional and modified stepped solar stills have been calculated as 0.0359 and 0.029$/(L·m^(-2)),respectively.

Controllable step-flow growth of GaN on patterned freestanding substrate

A new kind of step-flow growth mode is proposed,which adopts sidewall as step source on patterned GaN substrate.The terrace width of steps originated from the sidewall was found to change with the growth temperature and ammonia flux.The growth mechanism is explained and simulated based on step motion model.This work helps better understand the behaviors of step advancement and puts forward a method of precisely modulating atomic steps.

Stability analysis of intermittently jointed rock slopes based on the stepped failure mode

In practical engineering,due to the noncontinuity characteristics of joints in rock slopes,in addition to plane failure,stepped sliding failure may occur for intermittently jointed rock slopes.Especially for intermittently bedding jointed rock slopes,the correlation and difference in strength parameters between joints and rock bridges,along with the various failure modes and intermittency of rock bridges,contribute to the complexity of stepped failure modes and the unpredictability of failure regions.Based on the upper-bound limit analysis method and multi-sliders step-path failure mode,considering the shear and tensile failure of rock bridges and the weakened relationship between the strength parameters of rock bridges and jointed surfaces,by introducing the modified M-C failure criterion and the formula for calculating the energy consumption of tensile failure of rock bridges,two failure mechanisms are constructed to obtain the safety factor(F_(s))of intermittently jointed rock slopes.The sequential quadratic programming method is used to obtain the optimal upper-bound solution for F_(s).The influence of multiple key parameters(slope height H,horizontal distance L,Slope angleβ,shear strength parameters of the rock bridgeφr and cr,Dimensionless parameter u,weakening coefficients of the internal friction angle and cohesion between the rock bridges and joint surfaces Kφand Kc)on the stability analysis of intermittently jointed rock slopes under the shear failure mode of rock bridges as well as under the tensile failure mode is also explored.The reliability of the failure mechanisms is verified by comparative analysis with theoretical results,numerical results,and landslide cases,and the variation rules of F_(s)with each key parameter are obtained.The results show that F_(s) varies linearly withφr and cr of the rock bridge and with K_(φ)and K_(c),whereas F_(s)changes nonlinearly with H and L.In particular,with the increase in Kφand Kc,Fs increases by approximately 52.78%and 171.02%on average,respectively.For rock bridge tensile failure,F_(s) shows a nonlinearly positive correlation withφr,cr,Kφand Kc.In particular,with the increase in Kφand Kc,Fs increases by approximately 13%and 61.69%on average,respectively.Fs decreases rapidly with increasing slope gradientβand decreasing dimensionless parameterμ.When Kφand Kc are both less than 1.0,the stepped sliding surface occurs more easily than the plane failure surface,especially in the case of tensile failure of the rock bridge.In addition,rock slopes with higher strength parameters,taller heights,and greater weakening coefficients are prone to rock bridge tension failure with lower Fs,and more attention should be given to the occurrence of such accidents in actual engineering.

Qingdao Recommendations for the Protection and Return of Cultural Objects Removed from Colonial Contexts or Acquired by Other Unjustifiable or Unethical Means

The International Conference on the Protection and Return of Cultural Objects Removed from Colonial Contexts was held in Qingdao,China on June 20,2024.representatives from 28 countries and 2 international organizations attended the conference or shared ideas and communicated through video.

Transfer matrix method for free and forced vibrations of multi-level functionally graded material stepped beams with different boundary conditions

Functionally graded materials(FGMs)are a novel class of composite materials that have attracted significant attention in the field of engineering due to their unique mechanical properties.This study aims to explore the dynamic behaviors of an FGM stepped beam with different boundary conditions based on an efficient solving method.Under the assumptions of the Euler-Bernoulli beam theory,the governing differential equations of an individual FGM beam are derived with Hamilton’s principle and decoupled via the separation-of-variable approach.Then,the free and forced vibrations of the FGM stepped beam are solved with the transfer matrix method(TMM).Two models,i.e.,a three-level FGM stepped beam and a five-level FGM stepped beam,are considered,and their natural frequencies and mode shapes are presented.To demonstrate the validity of the method in this paper,the simulation results by ABAQUS are also given.On this basis,the detailed parametric analyses on the frequencies and dynamic responses of the three-level FGM stepped beam are carried out.The results show the accuracy and efficiency of the TMM.

Contribution to the Full 3D Finite Element Modelling of a Hybrid Stepping Motor with and without Current in the Coils

The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the two identical and coaxial half stators. The calculation of the field with or without current in the windings (respectively with or without permanent magnet) is done using a mixed formulation with strong coupling. In addition, the local high saturation of the ferromagnetic material and the radial and axial components of the magnetic flux are taken into account. The results obtained make it possible to clearly observe, as a function of the intensity of the bus current or the remanent induction, the saturation zones, the lines, the orientations and the magnetic flux densities. 3D finite element modelling provide more accurate numerical data on the magnetic field through multiphysics analysis. This analysis considers the actual operating conditions and leads to the design of an optimized machine structure, with or without current in the windings and/or permanent magnet.

谐波驱动系统Back-stepping滑模控制研究

针对谐波传动系统动力学模型中存在的柔性变形、摩擦和运动误差等非线性因素。为了提高系统的传动精度,针对系统非线性刚度和静态误差因素进行了建模,并提出了一种Back-stepping滑模控制方法。利用Lyapunov稳定性理论,证明了闭环系统的误差是一致有界的。仿真结果表明,与PID控制相比,采用Back-stepping滑模控制,系统传动误差曲线峰峰值减小66.63%;负载端角速率误差曲线峰峰值减小77.35%。Back-stepping滑模控制能有效地补偿系统传动误差,抑制其负载端的速度波动,提高了系统的传动精度。

A novel dynamic step size LMS optimization scheme for interference reducing in FBMC-QAM

Filter bank multicarrier quadrature amplitude modulation(FBMC-QAM)will encounter inter-ference and noise during the process of channel transmission.In order to suppress the interference in the communication system,channel equalization is carried out at the receiver.Given that the con-ventional least mean square(LMS)equilibrium algorithm usually suffer from drawbacks such as the inability to converge quickly in large step sizes and poor stability in small step sizes when searching for optimal weights,in this paper,a design scheme for adaptive equalization with dynamic step size LMS optimization is proposed,which can further improve the convergence and error stability of the algorithm by calling the Sigmoid function and introducing three new parameters to control the range of step size values,adjust the steepness of step size,and reduce steady-state errors in small step sta-ges.Theoretical analysis and simulation results demonstrate that compared with the conventional LMS algorithm and the neural network-based residual deep neural network(Res-DNN)algorithm,the adopted dynamic step size LMS optimization scheme can not only obtain faster convergence speed,but also get smaller error values in the signal recovery process,thereby achieving better bit error rate(BER)performance.

TWO-STEP TRICK TO HACK INTO CELLS

In the microscopic world of viruses and human cells,a high-stakes game of lock-picking is constantly unfolding.In a recent study published in Cell on July 3,researchers from Fudan University,ShanghaiTech University,and the Institute of Biophysics(IBP)under the Chinese Academy of Sciences cracked the code on how one particular coronavirus,HCoV-HKU1,manages to sneak its way into our cells using a cunning two-step approach(doi:10.1016/j.cell.2024.06.016).

以智慧启迪“完美贴合”的未来--对话雅视集团及STEPPER品牌高层

在追求舒适、精准的配戴体验之路上,从业者精进技艺、别出心裁,提出了多种创造性的解决方案,只为向完美更进一步。第三十五届中国国际眼镜业展览会上,雅视集团及旗下深圳司徕柏(光学)有限公司带来了STEPPER品牌的最新战略动向--STEPPER VISIONCARE,以及全新的AMOS(雅姆斯)智能系统,为行业呈现了其对极致舒适和精准视力保护的愿景。

基于STEP模式下的计算机专业课堂实践教学效果提升策略

本研究的目的在于探讨基于STEP模式的计算机专业课堂实践教学效果提升策略。本研究采用了文献研究和理论分析的方法,探讨了STEP模式在计算机专业课堂中的优势,并提出了提升教学效果的策略。研究结果表明,STEP模式在计算机专业课堂实践教学中有利于跨学科整合、解决实际问题、促进团队协作。为了提高教学效果,本研究提出了多元化教学手段、师资队伍培训、及时更新理论教材等策略。本研究的结论是,采用STEP模式并实施相应策略可以有效提升计算机专业课堂实践教学的效果,帮助学生更好地适应现实问题解决和职业需求。

STEP教育模式下的环境设计课程探讨——以荆楚文化主题商业空间设计课程为例

随着社会对创新型人才需求的增加,STEP(Software, Theory, Experiment, Project)教育模式凭借其融合软件技能、理论知识、实验操作与项目管理的教学理念,为环境设计专业提供了新的教学策略。以荆楚文化主题的商业空间设计课程为例,概述了STEP教育模式的内涵,分析了环境设计专业课程实行STEP教学模式的必要性,探讨了基于STEP教学模式的商业空间设计课程实施路径。旨在提升学生的设计实践能力、强化文化理解力,有力支持环境设计专业的人才培养,促进地方文化与设计教育的有机结合。