基于系统论的产品形态“Follows+”设计解析

产品形态的设计方法应是一个开放、发展的体系。根据物质型产品的属性要义及系统论,因循“Form follows+”的维度、逻辑及取向,“Follows+”的对象应指向物、人、环境等系统性要素,应涵盖产品形态作为客观物象的“造物之理”、作为能量与信息交换介质的“造物之能”与作为目的和思想载体的“造物之意”等,而与之对应的便是:形随理(Form follows reason)、形随能(Form follows ability)、形随意(Form follows meaning)。基于系统论的产品形态“Follows+”设计,仅可视作一种系统性解决产品形态设计问题的方式与策略,不可简单地理解为能够“医治百病的灵丹妙药”。

Strengthening Exchanges and Cooperation in the Northeast Asia Region Follows the Trend of the Times——Sidelights of the 10^(th) Northeast Asia Youth Forum

The 10thNortheast Asia Youth Forum,with the theme of China-ROK-Japan Youth Employment Guidance,sponsored by Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea was held in Seoul and Cheonan from August 12 to 17.Seventy five college students from 37 universities sent by China International Youth Exchange Center,Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea and Japan Society attended the Forum.Lee Boksil,Vice-Minister of Ministry of

Photographer Follows Progress of Rural Family

<Abstact> the 1994 Spring Festival Party held by China Central Television, a press photographer and the four large photos he had on display became one of the highlights of the event. The photos were taken in 1950, 1963, 1979 and 1994, respectively of an ordinary rural family in Zhejiang Province. They were selected from nearly 1,000 photos taken by the photographer on more than 50 visits to this family. They trace the changes of an ordinary Chinese family and vividly illustrate the historical changes that have taken place in New China. The photographer was Xu Yonghui, a senior reporter with Zhejiang Daily. In this issue we feature a few of his photos and a report which testify to those changes.

Wave Attenuation and Turbulence Driven by Submerged Vegetation Under Current-Wave Flow

A set of laboratory experiments are carried out to investigate the effect of following/opposing currents on wave attenuation.Rigid vegetation canopies with aligned and staggered configurations were tested under the condition of various regular wave heights and current velocities,with the constant water depth being 0.60 m to create the desired submerged scenarios.Results show that the vegetation-induced wave dissipation is enhanced with the increasing incident wave height.A larger velocity magnititude leads to a greater wave height attenuation for both following and opposing current conditions.Moreover,there is a strong positive linear correlation between the damping coefficientβand the relative wave height H_(0)/h,especially for pure wave conditions.For the velocity profile,the distributions of U_(min)and U_(max)show different patterns under combined wave and current.The time-averaged turbulent kinetic energy(TKE)vary little under pure wave and U_(c)=±0.05 m/s conditions.With the increase of flow velocity amplitude,the time-averaged TKE shows a particularly pronounced increase trend at the top of the canopy.The vegetation drag coefficients are obtained by a calibration approach.The empirical relations of drag coefficient with Reynolds and Keulegane-Carpenter numbers are proposed to further understand the wave-current-vegetation interaction mechanism.

Multi-circular formation control with reinforced transient profiles for nonholonomic vehicles:A path-following framework

This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the feature of spatial-temporal decoupling is devised for a group of vehicles guided by a virtual leader evolving along an implicit path,which allows for a circumnavigation on multiple circles with an anticipant angular spacing.In addition,notice that it typically imposes a stringent time constraint on time-sensitive enclosing scenarios,hence an improved prescribed performance control(IPPC)using novel tighter behavior boundaries is presented to enhance transient capabilities with an ensured appointed-time convergence free from any overshoots.The significant merits are that coordinated circumnavigation along different circles can be realized via executing geometric and dynamic assignments independently with modified transient profiles.Furthermore,all variables existing in the entire system are analyzed to be convergent.Simulation and experimental results are provided to validate the utility of suggested solution.

A Novel Prescribed-Performance Path-Following Problem for Non-Holonomic Vehicles

The issue of achieving prescribed-performance path following in robotics is addressed in this paper,where the aim is to ensure that a desired path within a specified region is accu-rately converged to by the controlled vehicle.In this context,a novel form of the prescribed performance guiding vector field is introduced,accompanied by a prescribed-time sliding mode con-trol approach.Furthermore,the interdependence among the pre-scribed parameters is discussed.To validate the effectiveness of the proposed method,numerical simulations are presented to demonstrate the efficacy of the approach.

Ground response and failure mechanism of gob-side entry by roof cutting with hard main roof

This study is the result of long-term efforts of the authors’team to assess ground response of gob-side entry by roof cutting(GSERC)with hard main roof,aiming at scientific control for GSERC deformation.A comprehensive field measurement program was conducted to determine entry deformation,roof fracture zone,and anchor bolt(cable)loading.The results indicate that GSERC deformation presents asymmetric characteristics.The maximum convergence near roof cutting side is 458 mm during the primary use process and 1120 mm during the secondary reuse process.The entry deformation is closely associated with the primary development stage,primary use stage,and secondary reuse stage.The key block movement of roof cutting structure,a complex stress environment,and a mismatch in the supporting design scheme are the failure mechanism of GSERC.A controlling ideology for mining states,including regional and stage divisions,was proposed.Both dynamic and permanent support schemes have been implemented in the field.Engineering practice results indicate that the new support scheme can efficiently ensure long-term entry safety and could be a reliable approach for other engineering practices.

How secure can we expect the surveillance policies to be after the implementation in T1 polyps with carcinoma?

Approximately 7%of the polyps resected endoscopically have an adenocarcinoma focus,with no previous endoscopic evidence of malignancy.This raises the question of whether endoscopic resection has been curative.Furthermore,there is no consensus on what the endoscopic and histological criteria for good prognosis are,the appropriate follow-up strategy and what are the long-term results.The aim of the retrospective study by Fábián et al was to evaluate the occurrence of local relapse or distant metastasis in those tumors that were resected endoscopically compared to those that underwent oncologic surgery.They concluded that,regardless of the treatment strategy chosen,there was a higher recurrence rate than described in the literature and that adherence to follow-up was poor.The management approach for an endoscopically benign polyp histologically confirmed as adenocarcinoma depends on the presence of any of the previously described poor prognostic histological factors.If none of these factors are present and the polyp has been completely resected en bloc(R0),active surveillance is considered appropriate as endoscopic resection is deemed curative.These results highlight,once again,the need for further multicentric clinical practice studies to obtain more evidence for the purpose of establishing appropriate treatment and follow-up strategies.

Evaluation of the Impact of Driver Behavior on Back of Queues Events in Work Zones Using the SHRP2 Naturalistic Driving Study Data

The SHRP2 Naturalistic Driving Study was used to evaluate the impact of various work zone and driver characteristics on back of queue safety critical events (crash, near-crash, or conflicts) The model included 43 SCE and 209 “normal” events which were used as controls. The traces included representing 209 unique drivers. A Mixed-Effects Logistic Regression model was developed with probability of a SCE as the response variable and driver and work zone characteristics as predictor variables. The final model indicated glances over 1 second away from the driving task and following closely increased risk of an SCE by 3.8 times and 2.9 times, respectively. Average speed was negatively correlated to crash risk. This is counterintuitive since in most cases, it is expected that higher speeds are related to back of queue crashes. However, most queues form under congested conditions. As a result, vehicles encountering a back of queue would be more likely to be traveling at lower speeds.

A Case of Investigation and Diagnosis of Immune Thrombocytopenic Purpura After Vaccination of COVID-19 Inactivated Vaccine

Objective:Analyze the relationship between inoculating one case of the COVID-19 inactivated vaccine(Vero cell)and immune thrombocytopenic purpura to provide a reference for the standardized handling of adverse events following immunization.Methods:According to the"National Monitoring Program for Suspected Adverse Reactions to Vaccinations,"an on-site investigation,data collection and analysis,expert group diagnosis,and medical association assessment were conducted on a case of immune thrombocytopenic purpura in District A of Chongqing after vaccination with the inactivated COVID-19 vaccine.The assessment report was delivered to the three relevant parties,the case was reviewed,and the experience was summarized.Results:The investigation and diagnosis by the district-level vaccination abnormal reaction expert group concluded that the disease that occurred after vaccination with the COVID-19 inactivated vaccine was secondary immune thrombocytopenic purpura,an abnormal reaction to the vaccination.The medical damage was classified as Level II Grade B.The vaccine production enterprise raised objections to this conclusion.After re-assessment by the municipal-level medical association,the conclusion was consistent with that of the district-level medical association.The vaccine production enterprise did not raise any further objections.Conclusion:Through active collaboration among district and municipal-level medical associations,disease control institutions,and vaccination units,the recipients have been promptly and effectively treated,providing financial support for their subsequent treatment and safeguarding their rights.The investigation and disposal procedures for adverse events following immunization in Chongqing are clear,and the mechanism is sound.It is necessary to continue strengthening the monitoring of adverse events following immunization according to the existing plan and to ensure timely and standardized handling.Simultaneously,it is crucial to strengthen vaccine management and vaccination management.

利用谱分析法估计GRACE Follow-On地球重力场的空间分辨率

利用轨道扰动引力谱和大地水准面累计误差谱分析的方法估计未来GRACE(gravity recovery and climateexperiment)Follow-On卫星反演地球重力场的空间分辨率。基于GRACE Follow-On卫星的轨道特性,计算其在高空所受到的径向扰动引力,并根据谱特性及星载加速度计的测量噪声水平分析该卫星能反演重力场的阶数。利用EGM96重力场模型分别计算200 km和250 km轨道高度处的扰动引力谱。分析其特性表明:在两个轨道高度处分别能反演281阶和242阶的地球重力场模型。给出大地水准面累计误差谱模型,并计算200 km和250 km轨道高度处大地水准面累计误差谱。分析其谱特性表明:在两个轨道高度处分别能反演至286阶和228阶的地球重力场模型。

Selection of optimal U-turn locations for indirect driveway left-turn treatments on urban streets

The location of U-turn bays is an important consideration in indirect driveway left-turn treatments.In order to improve the performance of right-turns followed by U-turns（RTUTs）,this study evaluates the impacts of the separation distances between driveway exits and downstream U-turn locations on the safety and operational performance of vehicles making RTUTs.Crash data are investigated at 179 selected roadway segments,and travel time data are measured using video cameras at 29 locations in the state of Florida,USA.Crash rate models and travel time models are developed based on data collected in the field.It is found that the separation distance between driveway exits and downstream U-turn locations significantly impacts the safety and operational performance of vehicles making right turns followed by U-turns.Based on the research results,the minimum and optimal separation distances between driveways and U-turn locations under different roadway conditions are determined to facilitate driver use of RTUTs.The results of this study can be used for future intersection improvement projects in China.

基于Leader-follower与人工势场的多移动机器人编队控制

目的提出一种基于Leader-follower法和人工势场法相结合的多移动机器人编队控制方法,从而克服传统Leader-follower法中由微分方程确定的控制率无法将队形控制与避障统一的缺点.方法确定关于参数l和φ的人工势场函数,通过控制参数l和φ,使多移动机器人保持预定队形;机器人follower通过主动避障方法躲避障碍物,确定一个总的人工势场控制队形和避障.结果算法能使多移动机器人系统成功地进行编队和避障.结论通过仿真试验,机器人系统能够顺利通过狭窄通道,躲避静态障碍物和动态障碍物,并在避障后恢复队形,顺利到达目标,算法简单,从而验证了算法的有效性.

采用Leader-follower和模糊反馈机制的机器鱼队形控制

在Leader-follower框架下的多机器鱼系统队形控制中,针对Leader和Follower相对独立及落后机器鱼离队等问题,在传统的Leader-follower队形控制算法中引入模糊反馈控制器进行反馈调节,使得领航机器鱼Leader能定时检查Follower的位置,将多机器鱼系统的队形控制问题转化为具有反馈调节的Follower跟踪Leader的位置和方向的问题,以增强多机器鱼队形控制的稳定性,更好地协同作业完成任务.仿真试验验证了所提出的方法能较好地实现多机器鱼系统的队形控制.

基于领导跟随的欠驱动船舶编队跟踪控制

针对具有三自由度欠驱动水面船舶编队控制问题,提出一种基于领导跟随(Leader/Follower)结构的欠驱动水面船舶队形跟踪控制方法。当系统接收到队形控制指令,每个欠驱动水面船舶按照自己在编队中的角色进行控制,其中Leader根据任务中的队形指令完成航迹跟踪控制,而Followers则依据Leader的信息和航行中任务中的队形指令完成航迹跟踪控制。在航迹跟踪控制中,根据期望队形任务指令为每个船舶设计需要跟踪的参考路径和速度指令;基于Lyapunov理论和重定义输出方法设计非线性速度控制器和路径跟踪控制器跟踪设计路径和速度指令;稳定性分析证明了队形跟踪误差是一致最终稳定的。仿真结果表明船舶可以跟踪任意期望曲线队形,从而验证了方法的有效性。

FIRST和FOLLOW集合的并行算法设计

描述了多处理机环境中 FIRST 和 FOLLOW 集合求解的一种并行处理方法,并讨论了 FIRST 和 FOLLOW 集合的并行算法设计思想和它的实现策略,在构造文法 G 的 LL(1)分析表以及判定文法 G 是否 LL(1)文法时,求解 FIRST 和 FOLLOW 集合是很重要的内容,由于文法中终结符和非终结符个数很多,考虑 FIRST 和 FOLLOW 集合的并行处理方法,对并行编译处理和提高效率有其理论和现实意义。

基于Vicsek模型的导弹集群建模分析

首先以Vicsek模型为基础,分析和建立了导弹集群模型;接着基于Vicsek模型中交互信息的思想,介绍了基于协调变量的集中式多导弹协同控制策略及Leader-follower协同策略。通过仿真研究说明了协同策略的有效性,进一步针对不同协同模型进行分析比较,为导弹集群攻击的具体实现提供参考。

Image-based Extraction of Characteristic Value of Pathological Leaf Surface

[ Objective] Computer image processing technology was used to distinguish the angular leaf spot and spotted disease in the agricultural production. [Method] The computer vision technology was used to carry out chromatic research on the plant pathological characteristics. The color and texture were taken as the plant disease image characteristic parameter to extract the perimeter, area and the shape of the lesion image, thus carrying out the classification judgment on the disease image. [ Result] C IE1976H IS chorma percentage histogram method was adopted to extract chromaticity characteristic parameters, the process was simple and effective with fast operation speed, eliminating the effect of leaf size and shape. The statistical characteristic parameter of chorma histogram was analyzed to obtain chroma skewness, which could significantly distinguish different symptoms of disease. [ Conclusion] The study suggested that chroma skewness could be adopted as the characteristic parameter to distinguish spotted disease with angular leaf spot.

The Teachers＇ Feedback Act Research of College English Classes

The Follow up Move Research has been deepening after it was first defined in 1975 by Sinclair and Coulthard, but it has not been paid attention in China, let alone study its effect in the classroom. In this essay based on the author＇s literature reading, the Follow up move functions and their language features are classified; its pragmatic motivations are researched and some factors which affect its relevance of occurrence are studied. Then with this guide of the frame four teachers classroom follow up moves are studied. Finally, the other scholars＇ findings in this field are commented and then the author＇s own insights are put forward.