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111.
112.
In this paper, we introduce an internet voting protocol which satisfies desired security requirements of electronic voting. In the newly proposed protocol, we allow the adversaries to get more power than in any previous works. They can be coercers or vote buyers outside, and corrupted parties inside our system. These adversaries also have ability to collude with each other to ruin the whole system. Our main contribution is to design an internet voting protocol which is unsusceptible to most of sophisticated attacks. We employ the blind signature technique and the dynamic ballots instead of complex cryptographic techniques to preserve privacy in electronic voting. Moreover, we also aim at the practical system by improving the blind signature scheme and removing physical assumptions which have often been used in the previous works. 相似文献
113.
High concentrations of manganese and iron in the Saigon River are major problems for the water supply in Ho Chi Minh City (HCMC), Viet Nam. To identify their sources and leaching processes, we surveyed water quality along the Saigon River and ran batch leaching tests using soil and sediment samples. Two important leaching processes were identified: acidic leaching from acid sulfate soil (ASS) in the middle reaches of the river, and Mn dissolution and Fe reduction from sediments in the downstream reaches. Low pH caused the concurrent release of Fe and Mn from the ASS. In contrast, anoxia caused the release of Fe but not Mn from the sediments, whereas low pH facilitated Mn dissolution. Sediments are a more important source of Mn because of their higher Mn contents (10 times) and release rates (14 times) than those from ASS. 相似文献
114.
Development of a quadruped walking robot AiDIN-III using biologically inspired kinematic analysis 总被引:1,自引:0,他引:1
Ig Mo Koo Duc Trong Tran Yoon Haeng Lee Hyungpil Moon Ja Choon Koo Sangdeok Park Hyouk Ryeol Choi 《International Journal of Control, Automation and Systems》2013,11(6):1276-1289
This paper presents a bio-inspired mechanism design for a quadruped walking robot. The approach is derived from the observation on the behaviors of quadruped locomotion, skeletal structure, and the study on the stability of walking based on morphological analysis. In the first, we define the design parameters such as the dimensions of the body and limbs, the center of mass position, and locomotion mechanisms based on surveys on the literatures from biologists. Then, by using the parameters, we propose an useful framework for determining the design parameters of a quadruped walking robot. For implementations, we manufacture a dog-type self-contained quadruped walking robot, named AiDIN-III (Artificial Digitigrade for Natural Environment version III) and the effectiveness of the proposed idea is validated via experimental works. 相似文献
115.
在软件需求增加和规模增大,却又要能做出及时交付给用户并且让用户满意的软件的时期,传统的软件工程方法显得有些力不从心,且已经遭到人们的质疑,而最近兴起的一种软件开发过程相关的技术,提供一些比较高效、实用的软件过程开发方法,这就是敏捷软件开发方法。测试驱动开发TDD(Test-Driven Development)是极限编程过程(一种敏捷开发)的重要特征,其对控制软件开发进度和开发质量有非常重要的作用。它的基本思想就是在开发前根据对将要开发的程序的要求,先写好所有测试代码,并且在开发过程中不时地通过运行测试代码来获得所开发的代码与所要求的结果之间的差距。这些活动的进行很大程度上依赖着程序的断言代码。因此断言代码的全面性及完整性深深地影响着一个程序的开发进度和质量。 相似文献
116.
OBJECTIVE: Muscle activity with and without the use of commercially available patient assistive devices during bed rising and lowering was quantified. BACKGROUND: Limited research is available in understanding or evaluating the physical benefits of assistive devices for patient use following major abdominal surgery. METHODS: Twenty healthy participants (9 men, 11 women) took part in a laboratory study to test the effects of device configuration (five levels) and bed elevation angle (0 degree and 30 degrees) on mean and peak upper and lower rectus abdominis and external oblique concentric and eccentric muscle activity. RESULTS: Reduced muscle activity was associated with the use of an assistive device, as compared with manual bed rising (unassisted). Positioning the devices at a higher anchor height and/or increasing the bed elevation angle further reduced muscle activity. Objective and subjective differences between the two assistive devices evaluated in the study were found. CONCLUSION: These results suggest that self-assistive devices may speed recovery because of reduced loads on damaged tissues. APPLICATION: Potential applications of this research include the assessment of other commercially available lift aids or comparisons of self-assistive lift aids with hospital-housed lift aids used to speed recovery rates. 相似文献
117.
We study the unsteady pulsatile flow of blood in an artery, where the effects of body acceleration are included. The blood is modeled as a modified second-grade fluid where the viscosity and the normal stress coefficients depend on the shear rate. It is assumed that the blood near the wall behaves as a Newtonian fluid, and in the core as a non-Newtonian fluid. This phenomenon is also known as the Fahraeus–Lindqvist effect. The equations are made dimensionless and solved numerically. 相似文献
118.
Semplore: A scalable IR approach to search the Web of Data 总被引:1,自引:0,他引:1
Haofen Wang Qiaoling Liu Thomas Penin Linyun Fu Lei Zhang Thanh Tran Yong Yu Yue Pan 《Journal of Web Semantics》2009,7(3):177-188
The Web of Data keeps growing rapidly. However, the full exploitation of this large amount of structured data faces numerous challenges like usability, scalability, imprecise information needs and data change. We present Semplore, an IR-based system that aims at addressing these issues. Semplore supports intuitive faceted search and complex queries both on text and structured data. It combines imprecise keyword search and precise structured query in a unified ranking scheme. Scalable query processing is supported by leveraging inverted indexes traditionally used in IR systems. This is combined with a novel block-based index structure to support efficient index update when data changes. The experimental results show that Semplore is an efficient and effective system for searching the Web of Data and can be used as a basic infrastructure for Web-scale Semantic Web search engines. 相似文献
119.
Bio-Inspired Artificial Fast-Adaptive and Slow-Adaptive Mechanoreceptors With Synapse-Like Functions
Hung Quang Huynh Tran Quang Trung Atanu Bag Trung Dieu Do M. Junaid Sultan Miso Kim Nae-Eung Lee 《Advanced functional materials》2023,33(42):2303535
Development of artificial mechanoreceptors capable of sensing and pre-processing external mechanical stimuli is a crucial step toward constructing neuromorphic perception systems that can learn and store information. Here, bio-inspired artificial fast-adaptive (FA) and slow-adaptive (SA) mechanoreceptors with synapse-like functions are demonstrated for tactile perception. These mechanoreceptors integrate self-powered piezoelectric pressure sensors with synaptic electrolyte-gated field-effect transistors (EGFETs) featuring a reduced graphene oxide channel. The FA pressure sensor is based on a piezoelectric poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) thin film, while the SA pressure sensor is enabled by a piezoelectric ionogel with the piezoelectric-ionic coupling effect based on P(VDF-TrFE) and an ionic liquid. Changes in post-synaptic current are achieved through the synaptic effect of the EGFET by regulating the amplitude, number, duration, and frequency of tactile stimuli (pre-synaptic pulses). These devices have great potential to serve as artificial biological mechanoreceptors for future artificial neuromorphic perception systems. 相似文献
120.
Ming Yi Thi Dao Nguyen Huan Liu Yafang Liu Shu Xiong Yan Wang 《Advanced functional materials》2023,33(26):2213471
Membrane decorated with biocides is an effective way to suppress biofilm growth. However, their immediate biocidal effect usually suffers from a significant decline due to the irreversible consumption of the biocides. Here, a smart nanofiltration membrane is reported with rechargeable antibacterial capability that is fabricated by a facile interfacial polymerization via 3-aminophenylboronic acid and trimesoyl chloride on a polysulfone substrate. Biocides bearing diol groups can be grafted onto the membrane surface under neutral/alkaline condition and then released from the surface under acidic environment, due to the pH-responsive feature of boronate ester complexes. The resultant membrane exhibits integrated properties of fast bacterial inactivating efficiency, rechargeable antibacterial capability, and impressive stability. In addition, the achieved membrane shows remarkable separation efficiency to dye/monovalent salt system. The successful fabrication of the membrane with rechargeable anti-bacterial property provides new insights into the development of pH-responsive and sustainable antibacterial membranes. 相似文献