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针对深层水域水下机器人通过机械臂捕捉目标物定位精度低、搜索难度大、耗费时间长的问题,提出一种基于多策略改进型麻雀搜索算法的水下机器人伸缩臂轨迹定位方法。通过D-H参数法搭建伸缩臂模型,结合MATLAB和ADAMS分析伸缩臂在水下捕捉目标物群目标物的低效性,引用麻雀搜索算法中鸟群觅食在最优位置的思想,引入Logistic混沌映射和柯西高斯变异原理,通过水下机器人的4项性能指标分析最优结果。结果表明:优化后的麻雀算法优于其他算法,同粒子群算法、天牛群算法、鲸鱼优化算法相比,伸缩臂捕捉目标物轨迹路线更加精确,水域环境下避障更为明显。 相似文献
23.
Recently, Hou et al. introduced a novel (2, n) privilege-based visual cryptography scheme (PVCS) with various privilege levels of shadow images. In this scheme, a shadow with a higher privilege contributes more recovered information, while a lower privileged shadow has the less recovery capability. Moreover, the visual quality of stacked result depends on the total sum of privilege levels for all involved shadows in reconstruction. Unfortunately, the PVC scheme has the inconsistency of the contrast of recovered image and the sum of privilege levels. Accordingly, an enhanced Hou et al.’s (2, n)-PVC scheme (EPVCS) is proposed to solve this inconsistency problem. However, the EPVCS is not a general solution to implement all PVCSs with arbitrary privilege levels, and it also has the unequal whiteness of shadows. In this paper, we first extend Hou et al.’s (2, n)-EPVCS with a correct privilege levels achieving the consistency of the contrast and the sum of privilege levels. Then we construct a (2, n)-PVCS to allow arbitrary privilege levels and provide the equal whiteness for each shadow. 相似文献
24.
Samta Gajbhiye Sanjeev Karmakar Monisha Sharma Sanjay Sharma 《Information Security Journal: A Global Perspective》2018,27(1):42-56
Secure Simple Pairing, a Bluetooth-pairing protocol, suffers from passive off-line and active online-guessing attack. These assaults are a direct result of the shortcomings in Bluetooth specification. Bluetooth technology uses the principles of device inquiry and inquiry scan. Scanning devices listen in on known frequencies for devices that are actively inquiring. If two Bluetooth devices know absolutely nothing about each other, one must run an inquiry to try to discover the other. One device sends out the inquiry request, and any device listening for such a request will respond with its address, and possibly its name, Input/Output capability and other information. Before connection, each device knows the address, their name, their capability, Quality-of-Service, etc. During pairing, Man-In-The-Middle attacker may capture all the information of connecting devices and impersonate them. This paper introduces the security augmentation in Bluetooth pairing by postponing exchange of Input-Output capability and other information like Quality-of-Service until it is essentially required and by casing the link key with a pair of Elliptic Curve Diffie-Hellman keys. Consequently, this leads to increased pairing time. Yet, we overlooked the increased pairing time, as the proposed Bluetooth-pairing protocol improves security by strengthening the link key. 相似文献
25.
《Information Security Journal: A Global Perspective》2013,22(4-6):151-161
ABSTRACTEmbedded systems are routinely deployed in critical infrastructures nowadays, therefore their security is increasingly important. This, combined with the pressing requirement of deploying massive numbers of low-cost and low-energy embedded devices, stimulates the evolution of lightweight cryptography and other green-computing security mechanisms. New crypto-primitives are being proposed that offer moderate security and produce compact implementations. In this article, we present a lightweight authenticated encryption scheme based on the integrated hardware implementation of the lightweight block cipher PRESENT and the lightweight hash function SPONGENT. The presented combination of a cipher and a hash function is appropriate for implementing authenticated encryption schemes that are commonly utilized in one-way and mutual authentication protocols. We exploit their inner structure to discover hardware elements usable by both primitives, thus reducing the circuit’s size. The integrated versions demonstrate a 27% reduction in hardware area compared to the simple combination of the two primitives. The resulting solution is ported on a field-programmable gate array (FPGA) and a complete security application with input/output from a universal asynchronous receiver/transmitter (UART) gate is created. In comparison with similar implementations in hardware and software, the proposed scheme represents a better overall status. 相似文献
26.
《Information Security Journal: A Global Perspective》2013,22(1):46-54
Abstract Biometrics can be defined as science by which an individual is identified through analyses of physical data and behavioral characteristics.1 The measurement of an individual's characteristics quantifies his or her physical, behavioral characteristics. The physically unique characteristics include, but are not limited to, fingerprints, hand or palm geometry, retina or iris scans, voice or facial characteristics, keystroke patterns, and gait. These presumably unique characteristics are used, in turn, to recognize (identify), authenticate, deny, or grant access based on the individual's characteristics. 相似文献
27.
Hung‐Yu Chien 《中国工程学刊》2013,36(3):527-532
Abstract Even though there have been many research studies on proxy signature schemes, only Shao's proxy multi‐signature scheme is based on the factoring problem (FAC). Unfortunately, Shao's scheme requires sequential signing operations and strict order of the modulus. It is not practical and not efficient. We, therefore, based on RSA cryptosystems, propose new proxy‐protected mono‐signature and proxy‐protected multi‐signature schemes. In contrast to their counterparts, our scheme allows parallel signing operations and also improves the signers’ computational performance. 相似文献
28.
《Information Security Journal: A Global Perspective》2013,22(5):267-271
ABSTRACT The fast exponentiation is a crucial one in any kind of public key cryptosystem. Lim-Lee proposed a method for an efficient exponentiation in elliptic curve by dividing n-bit scalar into equal length of simple scalars. In this paper, the general Lim-Lee method is further improved by using the signed binary window method and direct doublings. 相似文献
29.
《Information Security Journal: A Global Perspective》2013,22(4-5):245-249
ABSTRACT Laih and Kuo developed two highly secure and efficient signature schemes based on factoring and discrete logarithms. Unfortunately, their schemes require many keys for signing document and verifying signature. Li, Tzeng, and Hwang improved one of their schemes and managed to reduce the number of keys, but unfortunately the improved scheme was shown to be insecure by Qian, Chao, and Bao. In this paper, a new modified scheme of Li-Tzeng-Hwang is presented with two main results: The modified scheme requires fewer keys than the scheme by Laih and Kuo, and it is able to withstand many attacks including the one mentioned by Qian, Chao and Bao. 相似文献
30.
Mike Koss 《Cryptologia》2013,37(3):204-210
The Enigma Machine is a complex electromechanical device used by the Germans in World War II to achieve what they thought was complete communications security. While the original machine weighed over 20?lbs, the central mechanics of the machine can be simulated manually by manipulating strips of paper. A Paper Enigma is presented that can be cut out of a single sheet of paper. The resulting simulator is compatible with the electromechanical original in that messages can be encoded on one, and decoded on the other. Copies of The Paper Enigma can be downloaded from http://mckoss.com/crypto/enigma.htm. 相似文献