33 research outputs found
FuseFPS: Accelerating Farthest Point Sampling with Fusing KD-tree Construction for Point Clouds
Point cloud analytics has become a critical workload for embedded and mobile
platforms across various applications. Farthest point sampling (FPS) is a
fundamental and widely used kernel in point cloud processing. However, the
heavy external memory access makes FPS a performance bottleneck for real-time
point cloud processing. Although bucket-based farthest point sampling can
significantly reduce unnecessary memory accesses during the point sampling
stage, the KD-tree construction stage becomes the predominant contributor to
execution time. In this paper, we present FuseFPS, an architecture and
algorithm co-design for bucket-based farthest point sampling. We first propose
a hardware-friendly sampling-driven KD-tree construction algorithm. The
algorithm fuses the KD-tree construction stage into the point sampling stage,
further reducing memory accesses. Then, we design an efficient accelerator for
bucket-based point sampling. The accelerator can offload the entire
bucket-based FPS kernel at a low hardware cost. Finally, we evaluate our
approach on various point cloud datasets. The detailed experiments show that
compared to the state-of-the-art accelerator QuickFPS, FuseFPS achieves about
4.3 and about 6.1 improvements on speed and power efficiency,
respectively.Comment: conference for ASP-DAC 202
Robot-Assisted Trans-Esophageal Ultrasound and the Virtual Admittance-Based Master-Slave Control Method Thereof
Research on coal mine XR intelligent operation and maintenance system for complex collaborative tasks involving multiple humans and multiple robots
With the development of coal mine intelligence and the application of coal mine robots, an efficient collaboration between coal mine operators and coal mine robots plays a crucial role in the execution of complex underground tasks. To optimize the complex operational relationship of multiple coal mine operators and multiple robots, based on the concept of digital twin and extensive experience in the XR field, the research is conducted on the design and key technologies of XR intelligent operation and maintenance system for complex collaborative tasks involving multiple humans and multiple robots in coal mines. Firstly, for a typical scenario of collaboration between two types of coal mine operators (i.e central control operators and field control operators) and two types of coal mine robots (i.e. detection robots and operating robots) in complex tasks, the overall system architecture is designed. The system is divided into three parts: the physical subsystem, VR operation and maintenance subsystem, and AR operation and maintenance subsystem. The content, functions, and collaborative operation relationships among these three parts are introduced. Then, an analysis of key technologies related to the VR operation and maintenance subsystem, AR operation and maintenance subsystem, and communication networking is carried out. The solutions corresponding to each key technology are discussed, and the integration and operation of the two types of coal mine operators, two types of coal mine robots, and VR/AR operation and maintenance subsystem are implemented. Finally, a laboratory environment simulating complex underground conditions is set up to create a test site, where the task points and specific tasks are defined. The feasibility and effectiveness of the system are tested and verified. The experimental results show that the coal mine XR intelligent operation and maintenance system is able to function in collaborative situations between multiple humans and multiple robots corresponding to different complex tasks. Through the collaborative operation of the VR operation and maintenance subsystem and the AR operation and maintenance subsystem, the collaborative perception, decision-making, and control between virtual space and physical space can be achieved. This allows for the iterative optimization and verification of complex tasks in a physical space from a virtual space, forming an intelligent operational mode of human-human, human-robot, and robot-robot interactive collaboration
Design of a Novel Haptic Joystick for the Teleoperation of Continuum-Mechanism-Based Medical Robots
Continuum robots are increasingly used in medical applications and the masterâslave-based architectures are still the most important mode of operation in humanâmachine interaction. However, the existing master control devices are not fully suitable for either the mechanical mechanism or the control method. This study proposes a brand-new, four-degree-of-freedom haptic joystick whose main control stick could rotate around a fixed point. The rotational inertia is reduced by mounting all powertrain components on the base plane. Based on the design, kinematic and static models are proposed for position perception and force output analysis, while at the same time gravity compensation is also performed to calibrate the system. Using a continuum-mechanism-based trans-esophageal ultrasound robot as the test platform, a masterâslave teleoperation scheme with positionâvelocity mapping and variable impedance control is proposed to integrate the speed regulation on the master side and the force perception on the slave side. The experimental results show that the main accuracy of the design is within 1.6°. The workspace of the control sticks is â60° to 110° in pitch angle, â40° to 40° in yaw angle, â180° to 180° in roll angle, and â90° to 90° in translation angle. The standard deviation of force output is within 8% of the full range, and the mean absolute error is 1.36°/s for speed control and 0.055 N for force feedback. Based on this evidence, it is believed that the proposed haptic joystick is a good addition to the existing work in the field with well-developed and effective features to enable the teleoperation of continuum robots for medical applications
Investigation on the Energy-Absorbing Properties of Bionic Spider Web Structure
In recent years, spider webs have received significant attention due to their exceptional mechanical properties, including strength, toughness, elasticity, and robustness. Among these spider webs, the orb web is a prevalent type. An orb webâs main framework consists of radial and spiral threads, with elastic and sticky threads used to capture prey. This paper proposes a bionic orb web model to investigate the energy-absorbing properties of a bionic spider web structure. The model considers structural parameters such as radial line length, radial line cross-sectional diameter, number of spiral lines, spiral spacing, and spiral cross-sectional diameter. These parameters are evaluated to assess the energy absorption capability of the bionic spider web structure. Simulation results reveal that the impact of the radial line length and spiral cross-sectional diameter on the energy absorption of the spider web is more significant compared to the radial line cross-sectional diameter, the number of spiral lines, and spiral spacing. Specifically, within a radial line length range of 60â80 mm, the total absorbed energy of a spider web is inversely proportional to the radial line length of the web. Moreover, the number of spiral lines and spiral spacing of the spider web, when within the range of 6â10 turns and 4â5.5 mm, respectively, are proportional to the total energy absorbed. A regression equation is derived to predict the optimal combination of structural parameters for maximum energy absorption. The optimal parameters are determined as follows: radial line length of 63.48 mm, radial line cross-sectional diameter of 0.46 mm, ten spiral lines, spiral spacing of 5.39 mm, and spiral cross-sectional diameter of 0.48 mm
CpLEA5, the Late Embryogenesis Abundant Protein Gene from Chimonanthus praecox, Possesses Low Temperature and Osmotic Resistances in Prokaryote and Eukaryotes
Plants synthesize and accumulate a series of stress-resistance proteins to protect normal physiological activities under adverse conditions. Chimonanthus praecox which blooms in freezing weather accumulates late embryogenesis abundant proteins (LEAs) in flowers, but C. praecox LEAs are little reported. Here, we report a group of five LEA genes of C. praecox (CpLEA5, KT727031). Prokaryotic-expressed CpLEA5 was employed in Escherichia coli to investigate bioactivities and membrane permeability at low-temperature. In comparison with the vacant strains, CpLEA5-containing strains survived in a 20% higher rate; and the degree of cell membrane damage in CpLEA5-containing strains was 55% of that of the vacant strains according to a conductivity test, revealing the low-temperature resistance of CpLEA5 in bacteria. CpLEA5 was also expressed in Pichia pastoris. Interestingly, besides low-temperature resistance, CpLEA5 conferred high resistance to salt and alkali in CpLEA5 overexpressing yeast. The CpLEA5 gene was transferred into Arabidopsis thaliana to also demonstrate CpLEA5 actions in plants. As expected, the transgenic lines were more resistant against low-temperature and drought while compared with the wild type. Taken together, CpLEA5-conferred resistances to several conditions in prokaryote and eukaryotes could have great value as a genetic technology to enhance osmotic stress and low-temperature tolerance
An adaptive PSM mechanism in WLAN based on traffic awareness
Conference Name:2013 10th IEEE International Conference on Networking, Sensing and Control, ICNSC 2013. Conference Address: Evry, France. Time:April 10, 2013 - April 12, 2013.Institute of Electrical and Electronics; Engineers - Systems, Man and Cybernetics Society; University of Evry; GENOPOLE; IFSTTARWireless devices consume large amount of energy during wireless communication. Since the energy storage of battery is limited, improving energy efficiency has become an important approach to prolong the lifetime of device. IEEE 802.11 protocol supports power save mode (PSM) in wireless local area networks (WLANs). But the standard PSM cannot adapt to the changes of traffic load or channel conditions. Therefore, this paper proposes an adaptive PSM mechanism (APSM) which improves energy efficiency of wireless devices in a WLAN with access point (AP). According to the current channel condition and traffic load, the AP gives devices with different priorities when they fetch buffered packets. The devices can adaptively adjust listening intervals according to network traffic and adopt different congestion windows when the network topology changes. APSM has been implemented and evaluated in NS-2. The simulation results have shown that the device using APSM can save 58% energy at most compared with the one using the standard PSM. ? 2013 IEEE
The Impact of Transformation of Farmersâ Livelihood on the Increasing Labor Costs of Grain Plantation in China
Analyzing the recessive impacts of farmersâ livelihood transformation on the surging labor cost in grain production is conducive to finding optimization paths for grain production. This study developed the Residual Livelihood Ratio (RLR) and the Livelihood Simpson Index (LSI) to measure the transformation of farmersâ livelihood in China, and applied the multiple regression model to explore the influence of the transformation of farmersâ livelihood on the labor cost of grain production. The results show that because of the soaring increment in labor cost, the net profit of rice, wheat, and maize production decreased largely in China. The LSI increased, while the RLR decreased, which indicated that farmersâ livelihoods transitioned towards a more unbalanced incomeâexpenditure but more flexible employment. The Residual Livelihood Ratio; the mechanization input; the grain yield per unit area; the non-grain plantation degree; and the non-agricultural land use degree showed negative impacts on labor cost in grain production, whereas the Livelihood Simpson Index and Engelâs coefficient of farmers showed positive impacts on the labor cost. This paper proposes targeted policy implications for labor cost control of the grain production in China
Analyzing the public events' influence via open microblogging APIs
Conference Name:2012 International Conference on Machine Learning and Cybernetics, ICMLC 2012. Conference Address: Xian, Shaanxi, China. Time:July 15, 2012 - July 17, 2012.Hebei University; IEEE Systems, Man and Cybernetics Society; Chongqing University; South China University of Technology; Hong Kong Baptist UniversityMicroblog is a popular network platform in which people share personal experiences and discuss public events that they concern. Some researchers measure the influence of public events by analyzing the related messages on Microblog. We have found that web counters on web pages contain a lot of useful information. This paper proposes an evaluation model to provide several quantification indicators of public events' influence (PEI). PEI indicators are calculated by the data available from open microblogging APIs. For examples, the number of users' followers and the number of times that a message is forwarded and commented. The impacts of some important factors on PEI have also been studied, such as users' genders, users' geography locations and the processes of events. Extensive experiments have been carried out using data from Sina Weibo. The results show that public events have greater influence around the places where the events happen, and have more impacts to the male. Moreover, the proposed method can exactly capture the key times of one public event by observing the peaks of the PEI trajectory. ćź 2012 IEEE