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1.
Micromachines (Basel) ; 15(4)2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38675363

RESUMO

Physically unclonable functions (PUFs) are crucial for enhancing cybersecurity by providing unique, intrinsic identifiers for electronic devices, thus ensuring their authenticity and preventing unauthorized cloning. The SRAM-PUF, characterized by its simple structure and ease of implementation in various scenarios, has gained widespread usage. The soft-decision Reed-Muller (RM) code, an error correction code, is commonly employed in these designs. This paper introduces the design of an RM code soft-decision attack algorithm to reveal its potential security risks. To address this problem, we propose a soft-decision SRAM-PUF structure based on the elliptic curve digital signature algorithm (ECDSA). To improve the processing speed of the proposed secure SRAM-PUF, we propose a custom ECDSA scheme. Further, we also propose a universal architecture for the critical operations in ECDSA, elliptic curve scalar multiplication (ECSM), and elliptic curve double scalar multiplication (ECDSM) based on the differential addition chain (DAC). For ECSMs, iterations can be performed directly; for ECDSMs, a two-dimensional DAC is constructed through precomputation, followed by iterations. Moreover, due to the high similarity of ECSM and ECDSM data paths, this universal architecture saves hardware resources. Our design is implemented on a field-programmable gate array (FPGA) and an application-specific integrated circuit (ASIC) using a Xilinx Virtex-7 and an TSMC 40 nm process. Compared to existing research, our design exhibits a lower bit error rate (2.7×10-10) and better area-time performance (3902 slices, 6.615 µs ECDSM latency).

2.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(9): 1106-1112, 2023 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-37718423

RESUMO

Objective: To compare the effectiveness of TiRobot-assisted and C-arm X-ray fluoroscopy assisted percutaneous kyphoplasty (PKP) via pedicle of vertebra in the treatment of osteoporotic vertebral compression fracture (OVCF) of thoracic vertebrae. Methods: The clinical data of 85 patients with OVCF of thoracic vertebrae who were admitted between January 2020 and March 2023 and met the selection criteria was retrospectively analyzed including 40 patients (50 vertebrae) undergoing PKP assisted by TiRobot (group A) and 45 patients (50 vertebrae) undergoing PKP assisted by C-arm X-ray fluoroscopy (group B). There was no significant difference in the comparison of baseline data such as gender, age, body mass index, bone mineral density T-value, fracture segment, trauma history, and preoperative numerical rating scale (NRS) score, Oswestry disability index (ODI), and Cobb angle of injured vertebra between the two groups ( P>0.05). The effectiveness evaluation indexes of the two groups, including the operation time, the volume of injected cement, the times of fluoroscopies, the length of hospital stay, and the occurrence of postoperative complications were collected and compared. Anteroposterior and lateral X-ray films and CT of the injured vertebra were reviewed at 1 day after operation to observe whether there was cement leakage and to evaluate the distribution of cement in the injured vertebra. Before and after operation, pain was assessed using the NRS score, dysfunction was assessed using the ODI, and vertebral height recovery was assessed by measuring the Cobb angle of the injured vertebrae by X-ray films. Results: Both groups of patients successfully completed the operation, the operation time, the volume of injected cement, the times of fluoroscopies, and the length of hospital stay in group A were significantly less than those in group B ( P<0.05). The patients in two groups were followed up 4-12 months (mean, 9.6 months). Bone cement leakage occurred in 5 vertebrae in group A and 15 vertebrae in group B after operation, all of which leaked to the intervertebral space and around the vertebral body, and the patients had no obvious clinical symptoms. The difference of bone cement leakage between the two groups was significant ( P<0.05). No severe complication such as intraspinal leakage, infection, or vascular embolism was found in the two groups. At 1 day after operation, the distribution index of bone cement in group A was mostly grade Ⅴ, which was well dispersed; while in group B, it was mostly grade Ⅱ and grade Ⅴ; the difference of bone cement distribution index between the two groups was significant ( P<0.05). The NRS score, ODI, and Cobb angle of injured vertebra in both groups were significantly improved at 1 day after operation when compared with preoperative ones ( P<0.05). There was no significant difference in the difference of the above indexes between the two groups before and after operation ( P>0.05). Conclusion: TiRobot-assisted unilateral PKP in the treatment of OVCF of thoracic vertebrae is safe and effective, which can reduce the X-ray transmission times during operation, shorten the operation time, reduce the volume of bone cement injection, and thus decrease incidence of bone cement leakage.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas da Coluna Vertebral , Humanos , Vértebras Torácicas/cirurgia , Fraturas por Compressão/etiologia , Fraturas por Compressão/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Cimentos Ósseos , Estudos Retrospectivos
3.
Sci Rep ; 13(1): 8163, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208475

RESUMO

The origins of composite tiles, one of the oldest forms of roofing, are still unclear. This study is based on a set of over 5000 clay tile fragments excavated from a single context in the Qiaocun site on the Chinese Loess Plateau, dated to ~ 2400-2200 BCE (Early Longshan Period). By combining morphological measurement statistics, 3D modeling, computer-based simulations, and reference to historical and archaeological records, we reconstruct the earliest known composite-tile roofing techniques and demonstrate that tile production was under a low-level standardization, with manual control forming a key agent during the roofing process. The quantitative study of the composite roof tiles from Qiaocun was then placed in its archaeological context and compared with other sites on the Loess Plateau. It was found that tile-roofed buildings were, by necessity, community projects. Such structures served as nodes in larger social communication networks; additionally, their appearance was linked to intensified social complexity in public affairs during the Longshan Period. The invention of clay tiles was associated with the inception of thick rammed-earth walls which had sufficient strength to serve as load-bearing structures for heavy tiled roofs. The roof tiles excavated from Qiaocun site indicate that the Loess Plateau was a key center for the origin and spread of composite tiles and related roofing and construction methods, suggesting a Longshan-Western Zhou tradition of roofing techniques in East Asia.

4.
ScientificWorldJournal ; 2014: 630280, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25243220

RESUMO

A discrete bat algorithm (DBA) is proposed for optimal permutation flow shop scheduling problem (PFSP). Firstly, the discrete bat algorithm is constructed based on the idea of basic bat algorithm, which divide whole scheduling problem into many subscheduling problems and then NEH heuristic be introduced to solve subscheduling problem. Secondly, some subsequences are operated with certain probability in the pulse emission and loudness phases. An intensive virtual population neighborhood search is integrated into the discrete bat algorithm to further improve the performance. Finally, the experimental results show the suitability and efficiency of the present discrete bat algorithm for optimal permutation flow shop scheduling problem.


Assuntos
Algoritmos , Simulação por Computador , Design de Software , Simulação por Computador/normas
5.
ScientificWorldJournal ; 2014: 237102, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24967425

RESUMO

Bat algorithm (BA) is a novel stochastic global optimization algorithm. Cloud model is an effective tool in transforming between qualitative concepts and their quantitative representation. Based on the bat echolocation mechanism and excellent characteristics of cloud model on uncertainty knowledge representation, a new cloud model bat algorithm (CBA) is proposed. This paper focuses on remodeling echolocation model based on living and preying characteristics of bats, utilizing the transformation theory of cloud model to depict the qualitative concept: "bats approach their prey." Furthermore, Lévy flight mode and population information communication mechanism of bats are introduced to balance the advantage between exploration and exploitation. The simulation results show that the cloud model bat algorithm has good performance on functions optimization.


Assuntos
Algoritmos , Quirópteros , Modelos Teóricos , Animais , Comportamento Animal
6.
PLoS One ; 8(3): e58999, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23544050

RESUMO

Mollusk remains are abundant in archaeological sites in the Guanzhong Basin of Northwestern China, providing good opportunities for investigations into the use of mollusks by prehistoric humans. Here we report on freshwater gastropod and bivalve mollusks covering the time interval from about 5600 to 4500 cal. yrs BP from sites of Mid-Late Neolithic age. They are identified as Cipangopaludina chinensis and Unio douglasiae, both of which are currently food for humans. The shells are well preserved and have no signs of abrasion. They are all freshwater gastropods and bivalves found in pits without water-reworked deposits and have modern representatives which can be observed in rivers, reservoirs, and paddy fields in the studied region. Mollusk shells were frequently recovered in association with mammal bones, lithic artifacts, and pottery. These lines of evidence indicate that the mollusks are the remains of prehistoric meals. The mollusk shells were likely discarded into the pits by prehistoric humans after the flesh was eaten. However, these mollusk remains may not have been staple food since they are not found in large quantities. Mollusk shell tools and ornaments are also observed. Shell tools include shell knives, shell reaphooks and arrowheads, whereas shell ornaments are composed of pendants and loops. All the shell tools and ornaments are made of bivalve mollusks and do not occur in large numbers. The finding of these freshwater mollusk remains supports the view that the middle Holocene climate in the Guanzhong Basin may have been warm and moist, which was probably favorable to freshwater mollusks growing and developing in the region.


Assuntos
Moluscos/anatomia & histologia , Exoesqueleto/anatomia & histologia , Animais , Arqueologia , Bivalves/anatomia & histologia , Radioisótopos de Carbono , China , Gastrópodes/anatomia & histologia , Geografia , Humanos , Datação Radiométrica , Fatores de Tempo
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