525 research outputs found
Design of a multiple bloom filter for distributed navigation routing
Unmanned navigation of vehicles and mobile robots can be greatly simplified by providing environmental intelligence with dispersed wireless sensors. The wireless sensors can work as active landmarks for vehicle localization and routing. However, wireless sensors are often resource scarce and require a resource-saving design. In this paper, a multiple Bloom-filter scheme is proposed to compress a global routing table for a wireless sensor. It is used as a lookup table for routing a vehicle to any destination but requires significantly less memory space and search effort. An error-expectation-based design for a multiple Bloom filter is proposed as an improvement to the conventional false-positive-rate-based design. The new design is shown to provide an equal relative error expectation for all branched paths, which ensures a better network load balance and uses less memory space. The scheme is implemented in a project for wheelchair navigation using wireless camera motes. © 2013 IEEE
Improvement of tofu texture in China
Nowadays, in China, the problem of protein inadequacy still exists. To solve this problem,low cost, good quality vegetable proteins are considered to be one of the best choices. Amongthem, as a good vegetable protein resource, soybean has aroused the attention of manyresearchers. Tofu, a kind of soybean product, was invented in ancient time in China andnowadays, it is still a popular daily dish in some Asian countries like China, Japan, Korea, etcand is considered as a good vegetable protein resource. For the traditional food culture and thestyle of Chinese dishes, Chinese prefer hard tofu. At present, the production of tofu is mainlydone by small-scale factories with handmade way. Such kind of factories can produce hardtofu meeting the palatability of Chinese consumers. But, the shelf life of tofu is very short, insummer, only half a day, which limits the distribution of tofu. At the same time, the labordensity is higher, the quality control of tofu is mainly by experiences and a uniform quality isdifficult to be realized. In 1980s’, some industrial lines were imported. But, such kind ofindustrial production line uses glucono-delta-lactone (GDL) as coagulant. Tofu produced bythis way is somewhat acidic, which is not preferred by consumers, and the texture of tofu isvery soft, which is not suitable for most of the Chinese dishes. Lack of information onproducing hard tofu by industrial line limit the industrial production of hard tofu in China.Based on the present situation of hard tofu production in China, this study takes theimprovement of tofu texture in China as the objective.To improve the texture of tofu, firstly, a proper evaluation method for the texture of tofu isnecessary. Stress-strain, stress relaxation and creep tests were conducted. Results showed thatparameters from stress relaxation and creep behaviors analyzed by using viscoelastic models(taking Maxwell model, serialized by a Spring model and Dashpot model, and Vigot model,paralleled by a Spring model and a Dashpot model as primary models) can reflect both theviscous and elastic changes of tofu with different coagulants and protein concentrations. Itwas suggested that this viscoelastic evaluation method was effective for the texture evaluationof tofu.After determining the proper texture evaluation method for tofu, in this study, the effects ofsoymilk concentration (protein) concentration, types and concentration of different coagulants(CaSO4, GDL, MgCl2) on the texture of tofu and the effects of okara addition on the texture oftofu were investigated. For the improvement of tofu texture in China, from the view of proteinconcentration, types and concentration of coagulants, the addition of okara, followingconclusions were drawn:(1) A higher soymilk concentration (protein concentration) can lead to a harder tofu. Theviscosity of soymilk also increased with increasing the protein concentration. A too highviscosity might cause the difficulties of pipe transportation. In industrial practice, thebalance between protein concentration and a proper viscosity should be considered.(2) Different coagulants showed different properties to the tofu production. For CaSO4 andGDL, increasing the amount of coagulant resulted in a harder tofu. MgCl2 showed anarrow range of optimal concentrations and too high concentration of MgCl2 caused aductile break of tofu. When at the same concentration of protein, GDL and MgCl2 caninduce harder tofu than CaSO4. The reaction of MgCl2 with soy protein is rapider thanthat of GDL and CaSO4.(3) It is possible to add paste-like okara to soymilk for the production of tofu. At a certainrange, the texture of tofu was not significantly affected by the addition of okara. CaSO4showed different response to the addition of okara comparing with GDL. 15% addition ofokara increased the break stress of CaSO4-coagulated tofu while the addition of okaradecreased the break stress of GDL-tofu.Based on the results in this study, it can be suggested that for industrial hard tofuproduction in China, using properly high concentration of soymilk, mixture of coagulants,such as CaSO4 with MgCl2, GDL with MgCl2, increasing the concentration of coagulants likeCaSO4 and GDL and adding okara can be reasonable alternatives.Thesis (Ph. D. in Agriculture)--University of Tsukuba, (A), no. 3531, 2004.3.25Includes bibliographical reference
An AI-Driven Secure and Intelligent Robotic Delivery System
Last-mile delivery has gained much popularity in recent years, it accounts for about half of the whole logistics cost. Unlike container transportation, companies must hire significant number of employees to deliver packages to the customers. Therefore, many companies are studying automated methods such as robotic delivery to complete the delivery work to reduce the cost. It is undeniable that the security issue is a huge challenge in such a system. In this article, we propose an AI-driven robotic delivery system, which consists of two modules. A multilevel cooperative user authentication module for delivering parcel using both PIN code and biometrics verification, i.e., voiceprint and face verification. Another noncooperative user identification module using face verification which detects and verifies the identification of the customer. In this way, the robot can find the correct customer and complete the delivery task automatically. Finally, we implement the proposed system on a Turtlebot3 robot and analyze the performance of the proposed schema. Experimental results show that our proposed system has a high accuracy and can complete the delivery task securely
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Wireless mosaic eyes based robot path planning and control. Autonomous robot navigation using environment intelligence with distributed vision sensors.
As an attempt to steer away from developing an autonomous robot with complex centralised intelligence, this thesis proposes an intelligent environment infrastructure where intelligences are distributed in the environment through collaborative vision sensors mounted in a physical architecture, forming a wireless sensor network, to enable the navigation of unintelligent robots within that physical architecture. The aim is to avoid the bottleneck of centralised robot intelligence that hinders the application and exploitation of autonomous robot. A bio-mimetic snake algorithm is proposed to coordinate the distributed vision sensors for the generation of a collision free Reference-snake (R-snake) path during the path planning process. By following the R-snake path, a novel Accompanied snake (A-snake) method that complies with the robot's nonholonomic constraints for trajectory generation and motion control is introduced to generate real time robot motion commands to navigate the robot from its current position to the target position. A rolling window optimisation mechanism subject to control input saturation constraints is carried out for time-optimal control along the A-snake. A comprehensive simulation software and a practical distributed intelligent environment with vision sensors mounted on a building ceiling are developed. All the algorithms proposed in this thesis are first verified by the simulation and then implemented in the practical intelligent environment. A model car with less on-board intelligence is successfully controlled by the distributed vision sensors and demonstrated superior mobility
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