Usually, a proof of a theorem contains more knowledge than the mere fact that the theorem is true. For instance, to prove that a graph is Hamiltonian it suffices to exhibit a Hamiltonian tour in it; however, this seems to contain more knowledge than the single bit Hamiltonian/non-Hamiltonian.In this paper a computational complexity theory of the “knowledge” contained in a proof is developed. Zero-knowledge proofs are defined as those proofs that convey no additional knowledge other than the correctness of the proposition in question. Examples of zero-knowledge proof systems are given for the languages of quadratic residuosity and 'quadratic nonresiduosity. These are the first examples of zero-knowledge proofs for languages not known to be efficiently recognizable.

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The knowledge complexity of interactive proof-systems

argument is often, if not acrimonious, at least heated. It gives an impression of the fluidity of opinion on many fundamental ideas under discussion and of the urgency with which cardiac cyanosis in the newborn is regarded. When Dr. William Muscott says that the earliest he has operated for pulmonary stenosis is on an infant 3 days old, and Sir Russell Brock agrees that the earlier in the first month that operation is undertaken the better, and when Dr. Varco asks Dr. Senning 'so far as I know they have never yet catheterized any child intrauterine in Sweden, but they have done it through the delivery canal sometimes-would you tell us the indications of the Scandinavian group for catheterization in the immediate newborn period?', one is indeed being kept up with the times. But that was two years ago and already some of the questions then debated have since been answered. This beautifully printed and well-illustrated stiff paperbacked volume is, and will for a few years yet remain, an invaluable companion to a full-scale textbook on congenital heart disease.

Growth at Adolescence.

我的台灣, 看見心靈的故鄉 =2009林磐聳藝術與設計展

The past decade has witnessed the rapid evolution in blockchain technologies, which has attracted tremendous interests from both the research communities and industries. The blockchain network was originated from the Internet financial sector as a decentralized, immutable ledger system for transactional data ordering. Nowadays, it is envisioned as a powerful backbone/framework for decentralized data processing and data-driven self-organization in flat, open-access networks. In particular, the plausible characteristics of decentralization, immutability, and self-organization are primarily owing to the unique decentralized consensus mechanisms introduced by blockchain networks. This survey is motivated by the lack of a comprehensive literature review on the development of decentralized consensus mechanisms in blockchain networks. In this paper, we provide a systematic vision of the organization of blockchain networks. By emphasizing the unique characteristics of decentralized consensus in blockchain networks, our in-depth review of the state-of-the-art consensus protocols is focused on both the perspective of distributed consensus system design and the perspective of incentive mechanism design. From a game-theoretic point of view, we also provide a thorough review of the strategy adopted for self-organization by the individual nodes in the blockchain backbone networks. Consequently, we provide a comprehensive survey of the emerging applications of blockchain networks in a broad area of telecommunication. We highlight our special interest in how the consensus mechanisms impact these applications. Finally, we discuss several open issues in the protocol design for blockchain consensus and the related potential research directions.

/pdf/a-survey-on-consensus-mechanisms-and-mining-strategy-13qvwin6yd.pdf

A Survey on Consensus Mechanisms and Mining Strategy Management in Blockchain Networks

Post-activation potentiation (PAP) is induced by a voluntary conditioning contraction (CC), performed typically at a maximal or near-maximal intensity, and has consistently been shown to increase both peak force and rate of force development during subsequent twitch contractions. The proposed mechanisms underlying PAP are associated with phosphorylation of myosin regulatory light chains, increased recruitment of higher order motor units, and a possible change in pennation angle. If PAP could be induced by a CC in humans, and utilized during a subsequent explosive activity (e.g. jump or sprint), it could potentially enhance mechanical power and thus performance and/or the training stimulus of that activity. However, the CC might also induce fatigue, and it is the balance between PAP and fatigue that will determine the net effect on performance of a subsequent explosive activity. The PAP-fatigue relationship is affected by several variables including CC volume and intensity, recovery period following the CC, type of CC, type of subsequent activity, and subject characteristics. These variables have not been standardized across past research, and as a result, evidence of the effects of CC on performance of subsequent explosive activities is equivocal. In order to better inform and direct future research on this topic, this article will highlight and discuss the key variables that may be responsible for the contrasting results observed in the current literature. Future research should aim to better understand the effect of different conditions on the interaction between PAP and fatigue, with an aim of establishing the specific application (if any) of PAP to sport.

Factors Modulating Post-Activation Potentiation and its Effect on Performance of Subsequent Explosive Activities

The boom in the capabilities and features of mobile devices, like smartphones, tablets, and wearables, combined with the ubiquitous and affordable Internet access and the advances in the areas of cooperative networking, computer vision, and mobile cloud computing transformed mobile augmented reality (MAR) from science fiction to a reality. Although mobile devices are more constrained computationalwise from traditional computers, they have a multitude of sensors that can be used to the development of more sophisticated MAR applications and can be assisted from remote servers for the execution of their intensive parts. In this paper, after introducing the reader to the basics of MAR, we present a categorization of the application fields together with some representative examples. Next, we introduce the reader to the user interface and experience in MAR applications and continue with the core system components of the MAR systems. After that, we discuss advances in tracking and registration, since their functionality is crucial to any MAR application and the network connectivity of the devices that run MAR applications together with its importance to the performance of the application. We continue with the importance of data management in MAR systems and the systems performance and sustainability, and before we conclude this survey, we present existing challenging problems.

Mobile Augmented Reality Survey: From Where We Are to Where We Go

The purpose of this study was to investigate the effect of a combined heavy-resistance and running-speed training program performed in the same training session on strength, running velocity (RV), and vertical-jump performance (VJ) of soccer players. Thirty-five individuals were divided into 3 groups. The first group (n = 12, COM group) performed a combined resistance and speed training program at the same training session, and the second one (n = 11, STR group) performed the same resistance training without speed training. The third group was the control group (n = 12, CON group). Three jump tests were used for the evaluation of vertical jump performance: squat jump, countermovement jump, and drop jump. The 30-m dash and 1 repetition maximum (1RM) tests were used for running speed and strength evaluation, respectively. After training, both experimental groups significantly improved their 1RM of all tested exercises. Furthermore, the COM group performed significantly better than the STR and the CON groups in the 30-m dash, squat jump, and countermovement jump. It is concluded that the combined resistance and running-speed program provides better results than the conventional resistance training, regarding the power performance of soccer players.

The effect of a combined high-intensity strength and speed training program on the running and jumping ability of soccer players.

The purpose of this study was to investigate the postactivation potentiation effect after a heavy resistance stimulus (HRS) on running speed (RS). Fifteen amateur team game players (basketball, volleyball, handball, and soccer players), ages 18-23 years running the 30-m dash and the intermediate phase of 0-10 and 0-30 m sprints, were used to evaluate RS. Resistance training consisted of 10 single repetitions at 90% of 1 repetition maximum. The running tests were performed 3 times--(a) 3 minutes prior the HRS, (b) 3 minutes after the HRS, and (c) 5 minutes after the HRS--in separated training sessions. Results showed that RS was not affected 3 minutes after the resistance training, but it increased for both selected running phases (0-10 and 0-30 m) 5 minutes after the HRS (p < 0.05). These findings indicate that heavy resistance exercise improves 10- and 30-m sprint performance when performed 5 minutes after the exercise bout.

Postactivation potentiation effects after heavy resistance exercise on running speed.

Mobile augmented reality (MAR) applications are gaining popularity due to the wide adoption of mobile and especially wearable devices. Such devices often present limited hardware capabilities while MAR applications often rely on computationally intensive computer vision algorithms with extreme latency requirements. To compensate for the lack of computing power, offloading data processing to a distant machine is often desired. However, if this process introduces new constrains in the application, especially in terms of latency and bandwidth. If current network infrastructures are not ready for such traffic, we envision that future wireless networks such as 5G will rapidly be saturated by resource hungry MAR applications. Moreover, due to the high variance of wireless networks, MAR applications should not rely only on the evolution of infrastructures. In this article, we analyze MAR applications and justify their need for accessing external infrastructure. After a review of the existing network infrastructures and protocols, we define guidelines for future real-time and multimedia transport protocols, with a focus on MAR offloading.

Future Networking Challenges: The Case of Mobile Augmented Reality

The purpose of this study was to compare the acute effects of three different stretching protocols on balance, agility, reaction time and movement time of the upper limbs. Participants were thirty one female high school athletes (age = 17.3 ± 0.5 yr.). All participants performed one of the following protocols on different days: (a) 3 min jogging followed by 7 min static stretching (SS), (b) 3 min jogging followed by 7 min dynamic stretching (DS), and (c) 3 min jogging followed by 7 min of rest (NS). After the protocols participants performed the following tests: dynamic balance, 505 agility test, reaction time (time between a sound stimulus and release of a button) and movement time (movement of the upper extremity over a 0.5 m distance). The order of stretching protocols and performance tests were counterbalanced to avoid carryover effects. Repeated measures analysis of variance revealed significant main effects for all variables except reaction time. The DS protocol compared to SS performed significantly better in balance, agility and movement time. Additionally, the DS protocol compared to NS performed significantly better in agility. According to the results of the study, a DS protocol is more appropriate than SS for activities that require balance, rapid change of running direction (agility) and movement time of the upper extremities. Key pointsStatic stretching has a negative effect on balance and agility performance compared to dynamic stretching.There was no effect of the stretching protocols on reaction time.Dynamic stretching was more effective than static stretching for increasing movement time of the upper extremities.

http://www.jssm.org/hfpdf.php?volume=13&issue=2&page=403

Dimitris Chatzopoulos

Papers

Mobile Augmented Reality Survey: From Where We Are to Where We Go

The effect of a combined high-intensity strength and speed training program on the running and jumping ability of soccer players.

Postactivation potentiation effects after heavy resistance exercise on running speed.

Future Networking Challenges: The Case of Mobile Augmented Reality

Acute Effects of Static and Dynamic Stretching on Balance, Agility, Reaction Time and Movement Time