Mesh segmentation using feature point and core extraction

Mesh segmentation has become a necessary ingredient in many applications in computer graphics. This paper proposes a novel hierarchical mesh segmentation algorithm, which is based on new methods for prominent feature point and core extraction. The algorithm has several benefits. First, it is invariant both to the pose of the model and to different proportions between the model’s components. Second, it produces correct hierarchical segmentations of meshes, both in the coarse levels of the hierarchy and in the fine levels, where tiny segments are extracted. Finally, the boundaries between the segments go along the natural seams of the models.     

深化体制改革必须加强企业管理

针对目前有些企业在深化体制改革, 转换经营机制后仍存在以改代管, 以转代管, 忽视企业管理的片面做法, 指出转换经营机制, 建立现代企业制度是增强企业活力的必要条件, 实施科学管理则是企业生存和发展的基础。企业管理必须随着体制改革的深入发展而不断创新, 加强管理必须从更新观念, 完善法人治理结构, 大力培养管理人才, 建立以人为本的激励制度, 建立目标成本管理制度, 吸收和引进现代科学管理方法, 以及改革投资管理制度等方面着手。     

E-empowerment: Empowerment by the Internet

This article focuses on the concept of empowerment and the ways in which the Internet is being utilized as an empowering tool. This analysis ranges from the personal to the global levels and the consequences of that empowerment are also discussed. We propose a four-level model that serves to explain what we term E-empowerment and the effects that can be observed at each of the four levels, ranging from (1) the personal; (2) the interpersonal; (3) group; and (4) citizenship. The potential for future development of E-empowerment is also discussed.     

Castration prevents calcium channel blocker-induced gingival hyperplasia in beagle dogs

1. The purpose of this study was to investigate testosterone's role on the calcium channel antagonist oxodipine-inducing gingival hyperplasia in a dog model. 2. Two experiments were conducted using castrated and intact male dogs. Oxodipine was administered orally for 90 days, at a dose of 24 mg/kg/day. In the first experiment, the occurrence of gingival hyperplasia was evaluated. In the second, the gingival index (GI) and gingival hyperplasia index (GHI) were recorded and correlated with serum levels of testosterone. 3. A significant positive correlation between GI, GHI and plasma testosterone was noted. Castrated dogs were injected with testosterone, 4 months after the start of oxodipine treatment, while in the non-castrated dogs, administration of oxodipine was stopped. Castration correlated with lack of GH, while testosterone injection to the same dogs was associated with an increase of GI and GHI. 4. Since it is known that testosterone receptors are present in the gingiva, it is proposed that oxodipine-induced gingival hyperplasia could be mediated by the calcium channel blocker on plasma testosterone levels.     

Using obstacle analysis to identify contingency requirements on an unpiloted aerial vehicle

This paper describes the use of Obstacle Analysis to identify anomaly handling requirements for a safety-critical, autonomous system. The software requirements for the system evolved during operations due to an on-going effort to increase the autonomous system’s robustness. The resulting increase in autonomy also increased system complexity. This investigation used Obstacle Analysis to identify and to reason incrementally about new requirements for handling failures and other anomalous events. Results reported in the paper show that Obstacle Analysis complemented standard safety-analysis techniques in identifying undesirable behaviors and ways to resolve them. The step-by-step use of Obstacle Analysis identified potential side effects and missing monitoring and control requirements. Adding an Availability Indicator and feature-interaction patterns proved useful for the analysis of obstacle resolutions. The paper discusses the consequences of these results in terms of the adoption of Obstacle Analysis to analyze anomaly handling requirements in evolving systems.     

Chosen ciphertext attacks on lattice-based public key encryption and modern (non-quantum) cryptography in a quantum environment

Modern cryptography is based on various building blocks such as one way functions with or without trapdoors, pseudo-random functions, one way permutations with or without trapdoors, etc. In a quantum world some of the main candidates for these building blocks are broken. For instance, the security of the most popular public-key cryptosystem—RSA—is related to the difficulty of factoring large numbers, and is broken (in principle) by a quantum computer. We investigate some of the remaining candidates, and discuss the resulting “Post-Quantum Cryptography” (namely, the resulting “modern cryptography in a quantum environment”).     

On the a-posteriori error bounds for the solution of ordinary nonlinear differential equations

This paper advances a procedure to compute the a-posteriori error bounds for the solution of a wide class of ordinary differential equations with given initial conditions. The method is based on an iterative scheme which yields upper and lower bounds which approach each other. The convergence of these iterations is proved analytically. Application of the proposed method is demonstrated by several examples. The method is independent of the integration scheme used. Also, separate bounds for each component of the solution are specifically available as a function of time compared to the bound on the norm yielded by conventional methods.     

An ecology of ideology: theory and evidence from four populations

This paper analyzes the founding rates of two types of Jewishagricultural cooperatives, the moshav and the kibbutz, to showhow political ideology intersects with resource requirementsto produce competition and mutualism between organizations.These two populations, which share ideology and a resource base,competed with each other. They both enjoyed mutualism with thepopulation of credit cooperatives, which represented a kindredideology, but relied on different resources. They both sufferedcompetition from the population of corporations, which representeda rival ideology, capitalism.     

Attachment style as a predictor of behavior in group counseling with preadolescents.

This study investigated the role that attachment style plays in preadolescent behavior in group counseling. The study population consisted of 77 preadolescents referred to counseling services in their schools in Israel. They were treated in 11 small counseling groups led by novice counselors. Variables included self-disclosure, client behavior in therapy, and responsiveness to other group members--all assessed based on transcribed sessions. Participants also completed attachment questionnaires. The analyses were performed with hierarchical modeling (mixed) nesting individuals within groups. Results indicated differences on all dependent variables among the three attachment styles: secure, preoccupied, and avoidant. Secure adolescents showed the highest rates of self-disclosure, productive client behavior, and responsiveness to others, whereas avoidant participants showed the lowest scores on all measures. Gender, age, and group size showed little effect. The discussion focuses on implications for group therapists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

RSA-Based Undeniable Signatures

We present the first undeniable signatures scheme based on RSA. Since their introduction in 1989 a significant amount of work has been devoted to the investigation of undeniable signatures. So far, this work has been based on discrete log systems. In contrast, our scheme uses regular RSA signatures to generate undeniable signatures. In this new setting, both the signature and verification exponents of RSA are kept secret by the signer, while the public key consists of a composite modulus and a sample RSA signature on a single public message. Our scheme possesses several attractive properties. First, provable security, as forging the undeniable signatures is as hard as forging regular RSA signatures. Second, both the confirmation and denial protocols are zero-knowledge. In addition, these protocols are efficient (particularly, the confirmation protocol involves only two rounds of communication and a small number of exponentiations). Furthermore, the RSA-based structure of our scheme provides with simple and elegant solutions to add several of the more advanced properties of undeniable signatures found in the literature, including convertibility of the undeniable signatures (into publicly verifiable ones), the possibility to delegate the ability to confirm and deny signatures to a third party without giving up the power to sign, and the existence of distributed (threshold) versions of the signing and confirmation operations. Due to the above properties and the fact that our undeniable nsignatures are identical in form to standard RSA signatures, the scheme we present becomes a very attractive candidate for practical implementations. Received 25 July 1997 and revised 5 November 1998