Bipartite Threshold Multi-Secret Sharing Scheme Based on Hypersphere

To address the problem that existing bipartite secret sharing scheme is short of dynamic characteristic, and to solve the problem that each participant can only use secret share once, this paper proposed a bipartite (n1+n2, m1+m2)-threshold multi-secret sharing scheme which combined cryptography and hypersphere geometry. In this scheme, we introduced a bivariate function and a coordinate function over finite field Zp to calculate the derived points of secret share, which can reconstruct the shared secrets by producing the intersection point of hypernormal plane and normal line on the hypertangent plane. At the initial stage the secret dealer distributes to each participant a secret share that can be kept secret based on the intractability of discrete logarithm problem and need not be changed with updating the shared secrets.Each cooperative participant only needs to submit a derived point calculated from the secret share without exposing this secret share during the process of reconstructing the shared secret. Analyses indicate that the proposed scheme is not only sound and secure because of hypersphere geometric properties and the difficulty of discrete logarithm problem, but also efficient because of its well dynamic behavior and the invariant secret share. Therefore, this bipartite threshold multi-secret sharing scheme is easy to implement and is applicable in practical settings.

Applying two channels to vector space secret sharing based multi-signature scheme

Secret sharing and digital signature is an important research area in information security and has wide applications in such fields as safeguarding and legal use of confidential information, secure multiparty computation and electronic commerce. But up to now, study of signature based on general vector space secret sharing is very weak. Aiming at this drawback, the authors did some research on vector space secret sharing against cheaters, and proposed an efficient but secure vector space secret sharing based multi-signature scheme, which is implemented in two channels. In this scheme, the group signature can be easily produced if an authorized subset of participants pool their secret shadows and it is impossible for them to generate a group signature if an unauthorized subset of participants pool their secret shadows. The validity of the group signature can be verified by means of verification equations. A group signature of authorized subset of participants cannot be impersonated by any other set of partici- pants. Moreover, the suspected forgery can be traced, and the malicious participants can be detected in the scheme. None of several possible attacks can successfully break this scheme.

A Multi-Secret Sharing Scheme with Many Keys Based on Hermite Interpolation

A secret sharing scheme is one of cryptographies. A threshold scheme, which is introduced by Shamir in 1979, is very famous as a secret sharing scheme. We can consider that this scheme is based on Lagrange's interpolation formula. A secret sharing scheme has one key. On the other hand, a multi-secret sharing scheme has more than one keys;that is, a multi-secret sharing scheme has p (≥2) keys. Dealers distribute shares of keys among n participants. Gathering t (≤n) participants, keys can be reconstructed. In this paper, we give a scheme of a (t,n) multi-secret sharing based on Hermite interpolation, in the case of p≤t.

策略隐藏的高效多授权机构CP-ABE物联网数据共享方案

物联网环境下的数据共享存在效率低下、隐私泄露等问题,以及基于密文策略的属性基加密(ciphertext policy attribute-based encryption,CP-ABE)数据共享方案因采用单授权机构,需要承担繁重的计算工作而成为系统运行效率的瓶颈.为解决上述问题,提出一种策略完全隐藏的高效多授权机构CP-ABE物联网数据共享方案.该方案利用多授权机构CP-ABE实现数据的细粒度访问控制,利用联盟链不可篡改的特性保证密文哈希值和密钥集合密文的安全,采用MurmurHash3算法实现策略的完全隐藏,避免访问策略泄露用户隐私信息;并结合多秘密共享算法改进多授权机构CP-ABE,进而提升数据共享的效率.理论分析证明该方案能够保证访问策略和秘密共享过程的安全性.仿真实验结果表明,所提方案在策略隐藏和秘密分发过程中都具有较好的性能.

Anti-diabetic effects of Caulerpa lentillifera:stimulation of insulin secretion in pancreatic β-cells and enhancement of glucose uptake in adipocytes

Objective:To evaluate anti-diabetic effect of Caulrpa kntillifera(C.lentillifera).Methods:The inhibitory effect of C.lentillifera extract on dipeptidyl peptidase-IV and a-glucosidase enzyme was measured in a cell free system.Then,interleukin-1βand interferon-γinduced cell death and insulin secretion were measured in rat insulinoma(RIN)cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and ELISA kit,respectively.Glucose uptake and glucose transporter expression were measured by fluorometry and western blotting,using 3T3-Ll adipocytes.Results:C.lentillifera extract significantly decreased dipeptidyl peptidase-IV and a-glucosidase enzyme activities,and effectively inhibited cell death and iNOS expression in interleukin-1βand interfcron-γinduced RIK cells.Furthermore,C.lntillifera extract significantly enhanced insulin secretion in RTN cells and glucose transporter expression and glucose uptake in 3T3-L1adipocytes.Conclusions:Thus,our results suggest that C.lentillifera could be used as a potential antidiabetic agenl.

Selection Method of Multi-Objective Problems Using Genetic Algorithm in Motion Plan of AUV

To research the effect of the selection method of multi-objects genetic algorithm problem on optimizing result, thismethod is analyzed theoretically and discussed by using an autonomous underwater vehicle(AUV) as an object. A changingweight vtlue method is put forward and a selection formula is modified. Some experiments were implemented on an AUV.TwinBurger. The results shows that this method is effective and feasible.

Multi-features Based Approach for Moving Shadow Detection

In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence.

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects.

A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block

Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function.

Research on A Master - slave Multi - microcomputers Control System for Hollow Spindle Fancy Yarn Spinning Machine

In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardware construction, is introduced. Spinning experiments show that the system achieves satisfactory result. This system can solve the diftkultles of mechatronical fusion between domestic hollow splndk fancy yarn spuming muchine and its microcomputer control technology.

On the Representation of Multi-layer Woven Structure

A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the reinforcement of textile composites, the relationships among the structural parameters are derived for different binding patterns of the fabric structure. The conditions, which meet the requirements of structural cell stability,are also discussed.

Computer-aided Pattern Design of Multi-bar Warp Knitted Fabrics

To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the computer-aided pattern design of multi-barwarp knitted fabrics.In terms of the special propertiesof the computer-aided pattern design of multi-barwarp knitted fabrics,the Object Oriented Program(OOP)programming-Object Windows class Library(OWL)programming is selected.According to thecharacters of the OWL programming,various functionsare defined.Pattern design and technical parameters canbe output,which offers a great convenience for the fac-tory.

基于国密算法SM2和CP-ABE的医疗访问控制系统的设计与实现

针对现有的医疗数据共享方案存在运算开销大和权限控制问题,提出了一种基于可撤销的多属性机构授权方案和国密算法SM2的医疗数据访问控制系统。与传统的CP-ABE撤销算法相比,本文改进的CP-ABE算法不需要重新加密所有的加密文件以及不需要更新全部合法用户的密钥,只需更新与已撤销属性关联的密文。试验表明本文设计的系统在加解密性能上比传统的方案快出10%左右。此外,本文将多属性授权机构、灵活的可撤销机制、国密算法SM2和全球可信的证书颁发机构(CA)集成到CP-ABE中,能很好地保证系统的前向、后向、多属性授权机构之间通信的安全性并且能有效地抵抗伪造攻击和合谋攻击。

隐私保护的高效安全三方稀疏数据计算

如今,大数据与人工智能技术发展迅猛,基于海量数据进行精确训练的机器学习模型及其应用推动了生产力的提升,但同时也带来了严重的数据安全与隐私泄露问题,这一问题促进了隐私保护机器学习的研究.在实际应用中,机器学习算法常常在稀疏数据集上进行运算,明文下的模型训练存在高效计算方法,可以充分利用数据稀疏性,提高计算效率.为了保护数据隐私而引入的密码技术,将稀疏数据转化为稠密数据,从而使高效的稀疏数据运算变得复杂.现有的对于安全稀疏数据计算的相关研究都涉及大量公钥密码操作,计算效率不高,并且主要考虑两方的场景.实际上,稀疏数据的计算可简化为非零位置上相应元素的计算.为了充分利用这一特性以提高效率,本文将稀疏向量乘法问题分为了过滤和乘法计算两个模块来处理,并在三方联合计算的场景下进行协议设计.首先,基于三方加法复制秘密分享以及伪随机置换技术构建过滤协议,该协议能够实现对向量元素的过滤,筛选出向量中非零位置对应的元素.随后,在过滤协议的基础上引入加法同态加密技术,对非零元素进行安全乘法计算,实现一个隐私保护的安全三方稀疏向量乘法协议,并在半诚实敌手模型下,使用理想现实模拟范式证明了协议的安全性.最后,将隐私保护稀疏向量乘法协议应用到逻辑回归模型中,验证了其可用性.通过实验以及效率分析表明,相对于隐私保护稀疏矩阵乘法协议CAESAR,本文所提出的协议将主要计算开销由O(n)的密文运算次数,降低为O(m)次,其中n是向量的维数,m是向量中非零元素数量;在小批量的逻辑回归模型训练中,文本协议与通用安全多方计算框架ABY3相比有10%~30%的效率提升.

乳源外泌体的分泌提取及组学研究进展

外泌体是真核细胞分泌到细胞外的纳米级囊泡,携带蛋白质、核酸和脂质等,是细胞间信息传递的载体。它们广泛存在于生物体液中,包括母乳来源的外泌体,因其独特的功能特性而备受关注。然而,由于外泌体体积小且密度低,其提取过程面临诸多挑战,目前尚无一种能够快速、高效、高纯度、无损伤的提取外泌体的方法,导致外泌体的产量有限、纯度不高,进而限制了其在科学研究和临床领域的应用。本文综述了外泌体的提取和鉴定的最新技术进展,探讨了诱导体外细胞分泌外泌体的有效方法,并深入分析了母乳外泌体在蛋白、核酸及脂质组学方面的研究动态。这些研究不仅有助于我们更全面地了解母乳源外泌体的特性,而且为乳源外泌体替代母乳预防和治疗婴幼儿临床疾病提供了参考。

SHP-2酪氨酸磷酸酶激活突变促进组织白细胞浸润和器官损伤

目的观察SHP-2D61G/+酪氨酸磷酸酶激活突变对组织白细胞浸润、细胞因子分泌及多器官损伤的影响。方法分别以SHP-2D61G/+激活突变敲入的模型小鼠和野生型C57BL/6小鼠为研究对象,ELISA法检测小鼠血清和白细胞培养上清液中IL-2及TNF-α浓度;采用常规组织切片和HE染色观察心、肺、脾等组织病理学改变;放射免疫法检测血清中丙氨酸转氨酶和心肌肌钙蛋白I的水平。结果 SHP-2D61G/+激活突变小鼠脾、肺组织中白细胞浸润较野生型对照小鼠明显增加,心肌肥大,出现明显炎症损伤型组织学变化;与野生型对照相比,突变小鼠血清及白细胞培养上清液中IL-2和TNF-α浓度均显著增加(P<0.01),血清丙氨酸转氨酶及心肌肌钙蛋白I水平亦显著增高(P<0.01)。结论 SHP-2D61G/+激活突变增强白细胞分泌炎症因子的能力,促进组织白细胞严重浸润和脾、肺、心等多器官损伤,进而导致多器官功能障碍。

对基于单向函数的He-Dawson多步骤秘密共享方案的改进

在(t,n)门限秘密共享方案中,有n个参与者,至少t个参与者拿出自己的子秘密就能够同时重构m个秘密。He-Dawson提出了一个基于单向函数的多步骤秘密共享方案。但是他们的方案是一次方案而且不能抵抗合谋攻击。每个参与者的子秘密由参与者自己选取,所以不存在秘密分发者的欺骗。并且每个参与者能够验证其他合作者的欺骗。每个参与者选取的子秘密可以复用。并且组秘密可以以任意顺序重构。此方案还能够抵抗合谋攻击。本方案的安全是基于Shamir门限方案和RSA密钥体制。

无可信中心的秘密共享-多重签名方案的密码分析

首先,对一种新的无可信中心的秘密共享-多重签名方案进行分析,并提出了一种伪造攻击;利用这种攻击,攻击者可以很容易地伪造有效的秘密共享-多重签名,从而证明了该方案是不安全的.然后,对该方案进行了改进,在改进的方案中,参与签名的所有签名者共同决定签名所需的参数,而且达到规定门限个数的签名者共同合作才能生成有效的秘密共享-多重签名.最后,证明了改进后的方案具有更高的安全性,而且可以抵抗文中提出的攻击.

肝细胞癌和慢性乙型肝炎患者血清sFRP-1和β-catenin水平及临床意义

目的探讨肝细胞癌(hepatocellular carcinoma,HCC)和慢性乙型肝炎(chronic hepatitis B,CHB)患者血清分泌型卷曲相关蛋白-1(secreted frizzled-related proteins,sFRP-1)和β-catenin水平及临床意义。方法采用ELISA法检测36例HCC、36例CHB和36例正常人血清sFRP-1和β-catenin水平,应用Spearman相关分析,分析血清sFRP-1和β-catenin水平与年龄、丙氨酸氨基转移酶(ALT)、白蛋白和总胆红素等的相关性。结果 HCC和CHB患者血清sFRP-1水平分别为(1136.28±332.43)pg/ml和(1194.53±156.84)pg/ml,均显著低于正常人[(1477.26±563.12)pg/ml,P<0.05];HCC患者血清β-catenin水平为(527.2±20.9)pg/ml,显著高于正常人和CHB患者[分别为(369.8±21.5)pg/ml和(374.0±8.3)pg/ml,P<0.05];HCC和CHB患者血清sFRP-1和β-catenin水平与年龄、ALT、白蛋白、总胆红素无显著相关性。结论肝细胞癌和慢性乙型肝炎患者血清sFRP-1降低,而肝细胞癌患者血清β-catenin水平升高。