Turing Number: How Far Are You to A. M. Turing Award?

Welcome to the third issue of the ACM Computers in Entertainment magazine! In this exciting issue we present eight articles on a diversity of entertainment technology topics including Internet movie piracy, performing arts, animatronics, robotics, music, games, and interactive television. To get started, the Interviews section features video interviews with our distinguished advisory board members Leonard Kleinrock and Richard Edlund. Leonard talks about nomadic computing, embedded technology, smart spaces, ubiquitous computing, ethics, the roles of the government, and the future of the Internet. Richard speaks of movie visual effects, digital cinema, digital cameras, and technical Oscars. In the Movies and Performing Arts section, Sai Ho Kwok investigates the file-sharing patterns of pirated movies over BitTorrent peer-to-peer networks and offers suggestions on the design of an anti-piracy strategy. W. Scott Meador et al. describe an experimental dance performance featuring live-motion capture, real-time computer graphics, and multi-image projection produced by a cross-departmental team of faculty and students at Purdue University. In the Animatronics and Robotics section, Ray Dominey et al. discuss their integrated technology for raising the level of interactivity and realistic animatronics in amusement park dark rides. John D. Decuir et al. detail their use of Sonys AIBO entertainment robots to improve young childrens reading comprehension in a classroom setting. In the Music and Games section, Magy Seif El-Nasr et al. present a real-time lighting design to automatically adjust lighting in an interactive scene where the camera and character movements are unpredictable. Myriam Desainte-Catherine et al. examine their research on early-learning games using a joystick as a Dolabip instrument for electro-acoustic music education in schools. In the Synopsis - Books and Software section, Eddie Schwalb introduces the technologies, standards, and business issues for interactive television (iTV). Doug Twilleager et al. provide an overview of the server, desktop, and mobile technologies that are available to build a networked game with Java technology. I hope you will enjoy this issue of the online magazine. Before you dive into the exciting content, I would like to share with you the latest headline news about our distinguished editorial board advisors Alan Kay and Quincy Jones: On April 19, 2004, Dr. Alan Kay was named the 2003 winner of the A.M. Turing Award for pioneering many of the ideas at the root of contemporary object-oriented programming languages, leading the team that developed Smalltalk, and for fundamental contributions to personal computing. The A.M. Turing Award is the most prestigious technical award in computer science and is accompanied by a prize of $100,000. Earlier this year, Alan and his colleagues won the engineerings highest award - the Charles Stark Draper Prize from the National Academy of Engineering - for their vision, conception, and development of the worlds first practical networked personal computers. Both the Draper Prize and Turing Award are considered the equivalent of Nobel Prizes for their fields - engineering and computer science, respectively. In June, Alan was named winner of the 2004 Kyoto Prize in advanced technology, his third major scientific award this year. On May 16, 2004, nearly half a million people attended Mr. Quincy Jones all-star humanitarian concert "We Are the Future" at Romes Circus Maximus. In the tradition of "We Are the World,"the successful concert marked the launch of a worldwide initiative aspiring to create a sustainable chain of support for children in war-ravaged cities. The concert was broadcast on MTV, MTG/VIASAT, XM Radio, and Yahoo! webcasts. More information can be found at http://www.wearethefuture.com/concert_press.html I wish to express my admiration and gratitude to the legendary Alan Kay and Quincy Jones for their immense contributions to society. We are most fortunate to be working with the most innovative and philanthropic individuals in the world. A growing list of our distinguished editorial board members can be found at http://www.acm.org/pubs/cie/acmcie_editorial_board.pdf Now its time to dive into the magazine and send me your comments and feedback. Thank you very much for your continuing support. Sincerely, Newton Lee Editor-in-Chief ACM Computers in Entertainment Los Angeles June 2004

Herbert A. Simon, 1916-2001

Privacy preserving network publishing has been studied extensively in recent years. Although more works have adopted un-weighted graphs to model network relationships, weighted graph modeling can provide deeper analysis of the degree of relationships. Previous works on weighted graph privacy have concentrated on preserving the shortest path characteristic between pairs of vertices. Two common types of privacy have been proposed. One type of privacy tried to add random noise edge weights to the graph but still maintain the same shortest path. The other privacy, k-shortest path privacy, minimally perturbed edge weights so that there exists k shortest paths. However, the k-shortest path privacy only considers anonymizing same fixed number of shortest paths for all pairs of source and destination vertices. In this work, we present a new concept called [k1, k2]-shortest path privacy to allow different number of shortest paths for different pairs of vertices. A published network graph with [k1, k2]-shortest path privacy has at least k' indistinguishable shortest paths between the source and destination vertices, where k1 l k' l k2. A heuristic algorithm based on modifying only Non-Visited (NV) edges is proposed and experimental results showing the feasibility and characteristics of the proposed approach are presented.

On June 11, Vint Cerf and Bob Kahn received computing's highest prize, the A.M. Turing Award, from the Association for Computing Machinery. Their Transmission Control Protocol (TCP), created in 1973, became the language of the Internet.In the May 6 issue of Science [1], we used this as the "news hook" for an invited editorial on the current state of computer science research in the United States. "Where will the next generation of groundbreaking innovations in IT arise?" we asked. "Where will the Turing Awardees 30 years hence reside?" Our conclusion: "Given current trends, the answers to both questions will likely be 'not in the United States.'"We take this opportunity to explore in greater depth the issues we raised in that editorial. What are the trends that concern us? What can all of us, as computer scientists, do to reverse them?

Cryptography is concerned with the construction of schemes that withstand any abuse. A cryptographic scheme is constructed so as to maintain a desired functionality, even under malicious attempts aimed at making it deviate from its prescribed behavior. The design of cryptographic systems must be based on firm foundations, whereas ad hoc approaches and heuristics are a very dangerous way to go. These foundations were developed mostly in the 1980s, in works that are all co-authored by Shafi Goldwasser and/or Silvio Micali. These works have transformed cryptography from an engineering discipline, lacking sound theoretical foundations, into a scientific field possessing a well-founded theory, which influences practice as well as contributes to other areas of theoretical computer science. This book celebrates these works, which were the basis for bestowing the 2012 A.M. Turing Award upon Shafi Goldwasser and Silvio Micali. A significant portion of this book reproduces some of these works, and another portion consists of scientific perspectives by some of their former students. The highlight of the book is provided by a few chapters that allow the readers to meet Shafi and Silvio in person. These include interviews with them, their biographies and their Turing Award lectures.

The A. M. Turing Award is given each year to an individual for his technical contributions to computer science and engineering. Upon acceptance of the award, the winner delivers the annual Turing Lecture. Dr. McCarthy's presentation, “The Present Status ...

Jeffrey D. Ullman and Alfred V. Aho are recipients of the 2020 ACM A.M. Turing award. They were recognized for creating fundamental algorithms and theory underlying programming language implementation and for synthesizing these results and those of others in their highly influential books, which educated generations of computer scientists.

Computing the shortest path between two given locations in a road network is an important problem that finds applications in various map services and commercial navigation products. The state-of-the-art solutions for the problem can be divided into two categories: spatial-coherence-based methods and vertex-importance-based approaches. The two categories of techniques, however, have not been compared systematically under the same experimental framework, as they were developed from two independent lines of research that do not refer to each other. This renders it difficult for a practitioner to decide which technique should be adopted for a specific application. Furthermore, the experimental evaluation of the existing techniques, as presented in previous work, falls short in several aspects. Some methods were tested only on small road networks with up to one hundred thousand vertices; some approaches were evaluated using distance queries (instead of shortest path queries), namely, queries that ask only for the length of the shortest path; a state-of-the-art technique was examined based on a faulty implementation that led to incorrect query results. To address the above issues, this paper presents a comprehensive comparison of the most advanced spatial-coherence-based and vertex-importance-based approaches. Using a variety of real road networks with up to twenty million vertices, we evaluated each technique in terms of its preprocessing time, space consumption, and query efficiency (for both shortest path and distance queries). Our experimental results reveal the characteristics of different techniques, based on which we provide guidelines on selecting appropriate methods for various scenarios.

A hardware-efficient scheme and FPGA realization for computation of single pair shortest path for a mobile automaton

Given a spatial network and a collection of activity events (e.g., emergency requests, crime reports, accident reports, etc.), spatial network activity summarization (SNAS) finds a set of k shortest paths based on the activity events. SNAS is important for critical societal applications such as disaster response and crime analysis. SNAS is computationally challenging because of the potentially exponential search space wherein there are an exponential number of k subsets of all possible shortest paths in a spatial network. Previous work on SNAS has focused on either geometry or sub-graph based (e.g., only one path), and cannot summarize multiple routes in a spatial network. We propose a novel approach, called K-Main Routes (KMR), that discovers a set of k shortest paths to summarize activities. KMR can be considered a generalization of the well known K-means technique for network space. KMR uses inactive node pruning to reduce the number of shortest paths calculated by accounting only for active nodes. Experimental evaluation of KMR using a real-world data set demonstrates that KMR with inactive node pruning leads to substantial computational savings without reducing the coverage of the resulting summary paths. A case study that compares network based with geometry based summarization on a real-world data set is also presented.

This paper presents a study of analysis of minimum-time trajectories for a differential drive robot equipped with a fixed and limited field-of-view camera, which must keep a given landmark in view during maneuvers. Previous works have considered the same physical problem and provided a complete analysis/synthesis for the problem of determining the shortest paths. The main difference in the two cost functions (length vs. time) lays on the rotation on the spot. Indeed, this maneuver has zero cost in terms of length and hence leads to a 2D shortest path synthesis. On the other hand, in case of minimum time, the synthesis depends also on the orientations of the vehicle. In other words, the not zero cost of the rotation on the spot maneuvers leads to a 3D minimum-time synthesis. Moreover, the shortest paths have been obtained by exploiting the geometric properties of the extremal arcs, i.e., straight lines, rotations on the spot, logarithmic spirals and involute of circles. Conversely, in terms of time, even if the extremal arcs of the minimum-time control problem are exactly the same, the geometric properties of these arcs change, leading to a completely different analysis and characterization of optimal paths. In this paper, after proving the existence of optimal trajectories and showing the extremal arcs of the problem at hand, we provide the control laws that steer the vehicle along these arcs and the time-cost along each of them. Moreover, this being a crucial step toward numerical implementation, optimal trajectories are proved to be characterized by a finite number of switching points between different extremal arcs, i.e., the concatenations of extremal arcs with infinitely many junction times are shown to violate the optimality conditions.

To provide a model to estimate human resource needs for community-based mental health services in South Africa. A situation analysis was conducted of current community-based mental health service provision in South Africa, which comprise outpatient and emergency services, residential care and day care. Service utilisation rates and staffing needs were estimated for two levels of service coverage, using data from the situation analysis, local epidemiological studies and consultation with key stakeholders. For a population of 100,000 people, 7.3-23.8 full-time equivalent staff would be required to provide services in outpatient services, 14.9-41.6 in day care and 11.5-23.0 in residential care at minimum and full coverage levels respectively. The model can facilitate rational planning by requiring transparency and accountability in the assumptions used. This method can be adapted to a range of countries, by entering relevant country data. The model fills a gap, particularly in low- and middle-income countries, where community-based mental health services are sparse, and decisions regarding allocations to them are hampered by a lack of good quality data. The results of the model are limited by the quality of data and the assumptions upon which the modelling are based.

This paper introduces an active wave computing based algorithm for real-time robot navigation problem in dynamically changing environment and presents a real test setup with a roving robot. Travelling waves propagated on Cellular Neural Network (CNN) were employed by the system to find the shortest path as proposed in our previous work. The setup has a ceiling camera which captures an image of the top view of the platform at almost every one second. After preprocessing of this image, it is loaded to the network and an active wave which is generated by this network is propagated until the robot is covered by the wave. This method reduces the simulation time and speeds up the system. Although the robot is navigated in a dynamically changing environment, the system does not need to check the moving obstacles. The algorithm proposed here always generates a solution for the current state of the platform without the information about its past states. At every repetition of the algorithm, the target position is updated by the system if it is changed. Any change of the target position is immediately applied to the location of the wave source. Hence the system becomes working in dynamic environment with dynamic target.

We present a complete characterization of shortest paths to a goal position for a vehicle with unicycle kinematics and a limited range sensor, constantly keeping a given landmark in sight. Previous work on this subject studied the optimal paths in case of a frontal, symmetrically limited Field-Of-View (FOV). In this paper we provide a generalization to the case of arbitrary FOVs, including the case that the direction of motion is not an axis of symmetry for the FOV, and even that it is not contained in the FOV. The provided solution is of particular relevance to applications using side-scanning, such as e.g. in underwater sonar-based surveying and navigation.

Featuring agile controllability, high-level autonomy, and powerful field operational advantages, autonomous surface vessels (ASVs) are gaining increasing attention worldwide. Central to the control of ASVs, path planning is one of the key technologies that ensure the navigation safety. However, many of the previous works to solve the path planning problem are to find a collision-free and shortest path, but the solutions are not satisfied by the safety requirements and the non-holonomic constraints of ASVs. This paper expands on our previous work on the improved artificial fish algorithm (IAFSA) to address these challenges. The expanding technique is introduced to modify the grid cost, and a B-spline-based path smoother is applied to the algorithm to enhance its feasibility in cooperating with the ASV controller. Simulation experiments have been conducted to illustrate the effectiveness of the proposed method. Moreover, the new algorithm is tested in the USV control system model in a practical environment. The simulation results have demonstrated that the proposed method is more efficient than the other state-of-the-art algorithms, and the simulation with the ASV model illustrated its excellent performance cooperating with the control system. Therefore, the proposed method can be considered as a reliable algorithm to solve the path planning problem of ASVs.