Multi-Robot Collaborative Hunting in Cluttered Environments With Obstacle-Avoiding Voronoi Cells

This work proposes an online collaborative hunting strategy for multi-robot systems based on obstacle-avoiding Voronoi cells in a complex dynamic environment. This involves firstly designing the construction method using a support vector machine(SVM) based on the definition of buffered Voronoi cells(BVCs). Based on the safe collision-free region of the robots, the boundary weights between the robots and the obstacles are dynamically updated such that the robots are tangent to the buffered Voronoi safety areas without intersecting with the obstacles. Then, the robots are controlled to move within their own buffered Voronoi safety area to achieve collision-avoidance with other robots and obstacles. The next step involves proposing a hunting method that optimizes collaboration between the pursuers and evaders. Some hunting points are generated and distributed evenly around a circle. Next, the pursuers are assigned to match the optimal points based on the Hungarian algorithm.Then, a hunting controller is designed to improve the containment capability and minimize containment time based on collision risk. Finally, simulation results have demonstrated that the proposed cooperative hunting method is more competitive in terms of time and travel distance.

Multi-robot hunting strategy based on FIS and artificial immune algorithm

data is gathered to describe the relative location and relative motion state of the robots, which in turn forms the beginning stage of the fuzzy rule. The artificial immune algorithm optimizes and generates the rule data base and adaptive design considers factors in measuring the hunting efficiency. The optimized rules are applied to the hunting task and the results show that the algorithm can effectively actualize hunting of multiple mobile robots.

Integration of bio-inspired limb-like structure damping into motor suspension of high-speed trains to enhance bogie hunting stability

Hunting stability is an important performance criterion in railway vehicles.This study proposes an incorporation of a bio-inspired limb-like structure(LLS)-based nonlinear damping into the motor suspension system for traction units to improve the nonlinear critical speed and hunting stability of high-speed trains(HSTs).Initially,a vibration transmission analysis is conducted on a HST vehicle and a metro vehicle that suffered from hunting motion to explore the effect of different motor suspension systems from on-track tests.Subsequently,a simplified lateral dynamics model of an HST bogie is established to investigate the influence of the motor suspension on the bogie hunting behavior.The bifurcation analysis is applied to optimize the motor suspension parameters for high critical speed.Then,the nonlinear damping of the bio-inspired LLS,which has a positive correlation with the relative displacement,can further improve the modal damping of hunting motion and nonlinear critical speed compared with the linear motor suspension system.Furthermore,a comprehensive numerical model of a high-speed train,considering all nonlinearities,is established to investigate the influence of different types of motor suspension.The simulation results are well consistent with the theoretical analysis.The benefits of employing nonlinear damping of the bio-inspired LLS into the motor suspension of HSTs to enhance bogie hunting stability are thoroughly validated.

甘蓝型油菜全基因组cDNA FOX-hunting过表达文库构建

为系统解析甘蓝型油菜基因功能,结合FOX-hunting和Gateway重组技术,以4种激素和4种非生物胁迫处理的甘蓝型油菜幼苗根和叶片及成熟期种子和角果全长cDNA为混样,构建了全长cDNA FOX-hunting过表达文库。经检测,初级文库滴度为3.0×10^(6),库容为1.2×10^(7)CFU;次级FOX-hunting过表达文库滴度为2.6×10^(6),库容为1.04×10^(7)CFU。次级文库菌液PCR鉴定表明,阳性克隆率为96%,扩增均为250~3000 bp随机分布的单一条带,表明初级文库已较好地重组到pJVC55载体上。农杆菌转化后的克隆测序发现,140个克隆中有12个克隆为非特异扩增。GO富集分析发现剩余128个基因中,除21个基因功能富集于光合作用途径外,其余基因在转录因子和激酶中随机分布,且功能涉及器官发育、物质代谢和胁迫响应等多个方面。上述结果表明,本研究构建的甘蓝型油菜FOX-hunting过表达文库无功能偏向性、多态性丰富、完整性高,可作为油菜功能基因组的研究基础。

动脉瘤性蛛网膜下腔出血患者Hunt-Hess分级与并发症及功能障碍相关性分析

目的:探讨动脉瘤性蛛网膜下腔出血(aneurysmal subarachnoid hemorrhage,aSAH)患者的Hunt-Hess分级与并发症及神经系统功能障碍的相关性。方法:回顾性分析2011年10月到2021年10月收治的195例aSAH患者的临床资料,将Hunt-HessⅠ~Ⅲ级纳入低级别组(86例),Ⅳ~Ⅴ级纳入高级别组(109例)。比较2组患者的一般情况、量表评分、并发症及主要功能障碍,并将差异有统计学意义的指标进行多因素Logistic回归分析。结果:Hunt-Hess分级与脑积水(OR 2.850、95%CI 1.560~5.206),运动功能障碍(OR 3.522、95%CI 2.026~6.121),语言功能障碍(OR 1.928、95%CI 1.062~3.500),意识障碍(OR 3.662、95%CI 1.558~8.607),吞咽障碍(OR 2.383、95%CI 1.248~4.550)呈正相关;与年龄(OR 0.970、95%CI 0.945~0.996),继发脑梗死(OR 0.414、95%CI 0.227~0.754),Fugl-Meyer平衡评分(OR 0.890、95%CI 0.818~0.968),ADL评分(OR 0.983、95%CI 0.971~0.994)呈负相关。结论:Hunt-Hess高级别组的患者脑积水的发生比率更高,整体功能障碍更重,年轻患者的存活率更高;但Hunt-Hess级别高低,患者均有认知障碍的风险,应注意及时筛查并进行个体化康复。

Cool Hunting研究在产品创新设计中的应用

在市场竞争白热化的当下,用户体验日趋重要,如何让产品/服务更具前瞻性和创新性,更好地满足用户需求,我们引入了Cool Hunting研究,结合家电领域的特点,进行酷故事的收集与整理,并通过分析与酷创新,发现家电领域的产品/服务的创新机会,以期更好地满足市场和用户需求。

FOX Hunting System——一种新的功能基因筛选技术

FOX hunting system是近几年发展起来的又一新型分子生物学研究工具。在2006年,FOX hunting system作为一种植物功能获得性基因筛选技术首次被提出,可用于系统性阐明植物基因的功能。FOX hunting system可以在转基因植株中过量表达单个或有限数量的全长cDNA,这些异常表达的全长cDNA可能会导致显著的突变表型。根据研究目的对表型等方面发生改变的功能获得性突变植株进行筛选和解析,可以推断出转基因突变植株中所携带外源基因的功能。本文将就FOX hunting system的开发、流程、应用和发展等方面内容进行详细的阐述。

CT引导下经皮穿刺茎乳孔射频脉冲治疗Ramsay-Hunt综合征案例分析1例

患者,男,57岁,因咳嗽、咳痰1周入院。入院诊断考虑上呼吸感染,予以抗感染治疗后上呼吸道感染症状好转。但在入院第3天患者右侧口腔、颜面部、耳部出现大面积疱疹,部分伴有小脓疱,并且右侧颜面部皮损区域疼痛难忍,影响睡眠,视觉模拟评分法(visual analogue scale,VAS)评分8分。经多学科会诊后,诊断为Ramsay-Hunt综合征。按照House-Brackmann分级患者处于Ⅳ级,予以抗病毒、消炎止痛等治疗后,疱疹消退,皮损愈合,但疼痛程度无好转,并出现右侧面瘫,表现为右侧额纹消失、皱眉不能、闭目不全、鼻唇沟变浅、鼓腮漏气、口角偏向健侧等症状,伴有右耳耳鸣、听力下降。调整治疗方案,予以针灸及星状神经节阻滞治疗后,患者疼痛减轻,VAS评分2分,听力好转,但面瘫、耳鸣症状仍存在。在CT引导下经茎乳孔射频脉冲治疗,患者面瘫、耳鸣症状好转,VAS评分0分,House-Brackmann分级为Ⅰ级。

Influence of Vehicle Parameters on Critical Hunting Speed Based on Ruzicka Model

While introducing foreign advanced technology and cooperating with Chinese famous research institutes,the high-speed vehicles are designed and take the major task of passenger transport in China.In high-speed vehicle,the characteristic of shock absorber is an important parameter which determines overall behavior of the vehicle.The most existing researches neglect the influence of the series stiffness of the shock absorber on the vehicle dynamic behavior and have one-sided views on the equivalent conicity of wheel tread.In this paper,a high speed passenger vehicle in China is modeled to investigate the effect of the parameters taking series hydraulic shock absorber stiffness into consideration on Ruzicka model.Using the vehicle dynamic model,the effect of main suspension parameters on critical speed is studied.In order to verify the reasonableness of shock absorber parameter settings,vibration isolation characteristics are calculated and the relationship between suspension parameters and the vehicle critical hunting speed is studied.To study the influence of equivalent conicity on vehicle dynamic behavior,a series of wheel treads with different conicities are set and the vehicle critical hunting speeds with different wheel treads are calculated.The discipline between the equivalent conicity of wheel tread and critical speed are obtained in vehicle nonlinear system.The research results show that the critical speed of vehicle much depends on wheelset positioning stiffness and anti-hunting motion damper,and the series stiffness produces notable effect on the vehicle dynamic behavior.The critical speed has a peak value with the equivalent conicity increasing,which is different from the traditional opinion in which the critical speed will decrease with the conicity increasing.The relationship between critical speed and conicity of wheel tread is effected by the suspension parameters of the vehicle.The study results obtained offer a method and useful data to designing the parameters of the high speed vehicle and simulation study.

Influences of aerodynamic loads on hunting stability of high-speed railway vehicles and parameter studies

The influences of steady aerodynamic loads on hunting stability of high-speed railway vehicles were investigated in this study.A mechanism is suggested to explain the change of hunting behavior due to actions of aerodynamic loads：the aerodynamic loads can change the position of vehicle system（consequently the contact relations）,the wheel/rail normal contact forces,the gravitational restoring forces/moments and the creep forces/moments.A mathematical model for hunting stability incorporating such influences was developed.A computer program capable of incorporating the effects of aerodynamic loads based on the model was written,and the critical speeds were calculated using this program.The dependences of linear and nonlinear critical speeds on suspension parameters considering aerodynamic loads were analyzed by using the orthogonal test method,the results were also compared with the situations without aerodynamic loads.It is shown that the most dominant factors a ff ecting linear and nonlinear critical speeds are different whether the aerodynamic loads considered or not.The damping of yaw damper is the most dominant influencing factor for linear critical speeds,while the damping of lateral damper is most dominant for nonlinear ones.When the influences of aerodynamic loads are considered,the linear critical speeds decrease with the rise of cross wind velocity,whereas it is not the case for the nonlinear critical speeds.The variation trends of critical speeds with suspension parameters can be significantly changed by aerodynamic loads.Combined actions of aerodynamic loads and suspension parameters also a ff ect the critical speeds.The effects of such joint action are more obvious for nonlinear critical speeds.

An Exploration of the Relation between Hunting and Aggressiveness: Using Inmates Networks at Prison Secondary School as an Illustration

Aim of this research is to explore the relation of hunting with aggressiveness. For this purpose, two samples of prison inmates (who were students of the prison secondary school) were collected (class A = 23, class B = 12). The network indicators for superficial, idiosyncratic and strategic behavior (particularly, aggressiveness), applied in Bekiari and Hasanagas (2016), which were based on the primary network variables (outdegree, indegree, Katz status, pagerank, authority) were used. Non-network variables were also used for the criminal profile of the inmates. The data were sampled with questionnaire. Spearman test was conducted for detecting correlation between aggressiveness and hunting and Principal Component Analysis was used for formulating a typology. The following results were produced: The criminal profile seems hardly to be related with hunting experience or attitude. The relation of hunting experience and attitude with the superficial, idiosyncratic and strategic aggressiveness was examined. These three occasions of aggressiveness are expected to describe the incidental reaction, impulsive and adaptive reaction, respectively. The hunting is quite irrelevant to the incidental reaction. The impulsiveness seems to be more strongly correlated with hunting. In case of adaptiveness, there are many similarities with impulsiveness. The typology which is based on the existence (or not) of hunting experience seems to be more insightful, as it reveals a gradual involvement of aggressiveness dimensions, from incidentality to impulsiveness and further to adaptiveness. The following behavioral patterns of gradually enhanced aggressiveness appear: incidentally just provoking, impulsively being aggressive but without harming, and adaptively being aggressive and harming.

Self-organized search-attack mission planning for UAV swarm based on wolf pack hunting behavior

Cooperative search-attack is an important application of unmanned aerial vehicle(UAV)swarm in military field.The coupling between path planning and task allocation,the heterogeneity of UAVs,and the dynamic nature of task environment greatly increase the complexity and difficulty of the UAV swarm cooperative search-attack mission planning problem.Inspired by the collaborative hunting behavior of wolf pack,a distributed selforganizing method for UAV swarm search-attack mission planning is proposed.First,to solve the multi-target search problem in unknown environments,a wolf scouting behavior-inspired cooperative search algorithm for UAV swarm is designed.Second,a distributed self-organizing task allocation algorithm for UAV swarm cooperative attacking of targets is proposed by analyzing the flexible labor division behavior of wolves.By abstracting the UAV as a simple artificial wolf agent,the flexible motion planning and group task coordinating for UAV swarm can be realized by self-organizing.The effectiveness of the proposed method is verified by a set of simulation experiments,the stability and scalability are evaluated,and the integrated solution for the coupled path planning and task allocation problems for the UAV swarm cooperative search-attack task can be well performed.

Status of Wetland in Dhorpatan Hunting Reserve, Nepal

Wetland means the surface of the earth that is permanently or seasonally or partially covered with water. Wetlands are most productive areas for biodiversity and local livelihood support. Nepal ratified Ramsar convention in 1987 and started to include the wetland in Ramsar site and till now nine wetland sites are included in Ramsar site. There are still lacking systematic research and conservation approach for these wetlands;therefore, our study attempted to assess the status of wetlands in the Dhorpatan Hunting Reserve, Nepal;and explored threats and conservation challenges. We prepared list of streams and lakes and collected detail information regarding area, district, block, elevation and cultural as well as ecological importance of lakes. We recorded total 11 lakes with total 304477 m2 areas. The Sundaha lake is largest lake of the reserve having significant religious importance. We also recorded 7 streams in the reserve. Wetlands of the reserve were facing problem of sedimentation, pollution, and change in climate has also effects on these wetland ecosystem and their importance.

Hunting problems of multi-quadrotor systems via bearing-based hybrid protocols with hierarchical network

Bearing-based hunting protocols commonly adopt a leaderless consensus method,which requests an entire state of the target for each agent and ignores the necessity of collision avoidance.We investigate a hunting problem of multi-quadrotor systems with hybrid bearing protocols,where the quadrotor systems are divided into master and slave groups for reducing the onboard loads and collision avoidance.The masters obtain the entire state of the target,whose hybrid protocols are based on the displacement and bearing constraints to maintain formation and to avoid the collision in the hunting process.However,the slaves’protocols merely depend on the part state of the masters to reduce loads of data transmission.We also investigate the feasibility of receiving the bearing state from machine vision.The simulation results are given to illustrate the effectiveness of the proposed hybrid bearing protocols.

Feedback Control for Ecosystem Management:The Case of Wolf-Elk-Hunting Dynamics in the US Mountain West

The purpose of this paper is to explore the promise of utilizing some relatively new feedback control techniques in ecosystem management. First, we set forth a basic ecological-economic model of a predator-prey-hunting system in which both the predator and prey have use(flow) and non-use(stock) value and when the predator can inflict transboundary damages. We then use new data from the US Mountain West to show how a particular feedback approach—linear parameter-varying(LPV) control—can be utilized in this context. Our LPV model is able to quantify the cost of managing disturbances that inevitably arise as a manager tries to keep the actual path of the system "close" to its optimum. The results suggest management strategies in mountain ecosystems that feature large, mammalian carnivores.

Research on hunting stability and bifurcation characteristics of nonlinear stochastic wheelset system

A stochastic wheelset model with a nonlinear wheel-rail contact relationship is established to investigate the stochastic stability and stochastic bifurcation of the wheelset system with the consideration of the stochastic parametric excitations of equivalent conicity and suspension stiffness.The wheelset is systematized into a onedimensional(1D)diffusion process by using the stochastic average method,the behavior of the singular boundary is analyzed to determine the hunting stability condition of the wheelset system,and the critical speed of stochastic bifurcation is obtained.The stationary probability density and joint probability density are derived theoretically.Based on the topological structure change of the probability density function,the stochastic Hopf bifurcation form and bifurcation condition of the wheelset system are determined.The effects of stochastic factors on the hunting stability and bifurcation characteristics are analyzed,and the simulation results verify the correctness of the theoretical analysis.The results reveal that the boundary behavior of the diffusion process determines the hunting stability of the stochastic wheelset system,and the left boundary characteristic value cL=1 is the critical state of hunting stability.Besides,stochastic D-bifurcation and P-bifurcation will appear in the wheelset system,and the critical speeds of the two kinds of stochastic bifurcation decrease with the increase in the stochastic parametric excitation intensity.

基于几何法的三自由度平面并联机器人的Hunt奇异研究

首先,以3条支链直线交于同一点为判定准则,推导机器人的Hunt奇异曲面方程。研究发现,3‑转动副移动副转动副(Revolute‑joint,prismatic‑joint,revolute‑joint,RPR)平面并联机器人的Hunt奇异曲面方程与运用雅可比代数法得到的输出奇异曲面方程完全相同,即两曲面重合。其次,辨识出该机器人4类较常见的Hunt奇异位形,并将它们的奇异轨迹描绘在奇异曲面上,有助于揭示奇异位形之间的关系。接着,设计了3种特殊结构的3‑RPR平面并联机器人,并分析了它们的Hunt奇异性。结果表明,该机器人的Hunt奇异特性对几何结构的依赖性较大。最后,通过虚拟样机和实物样机的实验,论证了3‑RPR平面并联机器人的Hunt奇异性。

DYNAMIC HUNTING EXTREMUM CONTROL METHOD BASED ON MEASURE AND ESTIMATION

Objective To propose a dynamic hunting extremum control method based on comparison of the estimated value and measured value. Methods The output linear group of the system is approximately expressed as an nth order system with large time constant or with time delay. Moreover, the relation between input drive reversal of the logic circuit and dynamic output of the system is analyzed in detail. The calculating formulae for the drive reversal are given for different extremum control systems. Based on principles above, a controller using a micrprocessor and a testing laboratory plant were designed and implemented. Results With this new method, the controller achieves fast optimum point hunting process, good performance in extremum control systems for high order processes, and robust result under sudden change or drift of the extremum characteristics. Conclusion The new control owns the merits of rapid optimizing dynamics, robusticity, and wide applicability.

Tree stand falls: A persistent cause of neurological injury in hunting

AIM: To characterize and compare our current series of patients to prior reports in order to identify any changes in the incidence of neurological injury related to hunting accidents in Rochester, New York.METHODS: All tree stand-related injuries referred to our regional trauma center from September 2003 through November 2011 were reviewed. Information was obtained from the hospital's trauma registry and medical records were retrospectively reviewed for data pertaining to the injuries.RESULTS: Fifty-four patients were identified. Ninetysix percent of patients were male with a mean age of 47.9 years(range 15-69). The mean Injury Severity Score was 12.53 ± 1.17(range 2-34). The average height of fall was 18.2 feet(range 4-40 feet). All patients fell to the ground with the exception of one who landed on rocks, and many hit the tree or branches on the way down. A reason for the fall was documented in only 13 patients, and included tree stand construction(3), loss of balance(3), falling asleep(3), structural failure(2), safety harness breakage(3) or lightheadedness(1). The most common injuries were spinal fractures(54%), most commonly in the cervical spine(69%), followed by the thoracic(38%) and lumbar(21%) spine. Eight patients required operative repair. Head injuries occurred in 22%. Other systemic injuries include rib/clavicular fractures(47%), pelvic fractures(11%), solid organ injury(23%), and pneumothorax or hemothorax(19%). No patient deaths were reported. The average hospital length of stay was 6.56 ± 1.07 d. Most patients were discharged home without(72%) or with(11%) services and 17% required rehabilitation. CONCLUSION: Falls from hunting tree stands are still common, with a high rate of neurological injury. Compared to a decade ago we have made no progress in preventing these neurological injuries, despite an increase in safety advances. Neurosurgeons must continue to advocate for increased safety awareness and participate in leadership roles to improve outcomes for hunters.

Birds of Dhorpatan Hunting Reserve, Nepal

Nepal is rich in bird diversity and recorded 871 bird species. Our study aimed to update bird diversity of Dhorpatan Hunting Reserve (DHR) of Nepal which is an Important Birds Area (IBA) out of 27 IBAs of Nepal. One hundred forty nine species of birds were recorded in DHR;out of them Catreus wallichii was globally threatened bird which has faced different anthropogenic problem. Twelve species of birds were included in CITIES Appendices and 3 species were nationally threatened. Most of the species of order Passeriformis were recorded. Only one species of order Upupiformes i.e. Upupa epops was recorded during the study.