A design-aware test code approach for code writing problem in Java programming learning assistant system

To advance Java programming educations, we have developed the web-based Java programming learning assistant system (JPLAS) that provides the code writing problem. This problem asks a student to write a source code for a given assignment, where the correctness is verified by running the test code on JUnit. In this paper, we propose a design-aware test code approach for the code writing problem. The design-aware test code tests any important method in the model source code that has the advisable design for the assignment. Thus, by writing a code that can pass it, a student is expected to implement the code with the proper classes/methods in the model code. In evaluations of the proposal, all the students could complete highly qualitative codes for five graph algorithms using the design-aware test codes, where the code quality metrics were measured by metrics plugin for Eclipse

A proposal of a minimal-state processing search algorithm for isochronous channel reuse problems in DQDB networks

The IEEE 802.6 MAC standard protocol defines the distributed-queue dual bus (DQDB) for metropolitan area networks (MANs). The isochronous channel reuse problem (ICRP) has been studied for the efficient use of DQDB. Given a set of established connections and a set of connection requests, the goal of ICRP is to maximize the number of satisfied requests by finding a proper channel assignment, such that no established connection is not only reassigned a channel, but also any pair of active connections does not interfere each other. We propose a minimal-state processing search algorithm for ICRP (MIPS/sub -/ICRP). The simulation results show that MIPS/sub -/ICRP always provides near-optimum solutions

Compact tree plus algorithms for application-level multicast communications in multihome networks

Application-level multicast (ALM) communications replicate packets on host level to deliver them from a single source to multiple clients, so that it can efficiently realize a variety of network applications using moving pictures such as video conferences, distance learning, and video-on-demands. In this paper, we propose the CT+ (compact tree plus) algorithm for finding a better ALM routing tree in terms of delay minimization between hosts. CT+ consists of a tree construction stage from the existing CT algorithm, and a newly added iterative tree improvement stage. Then, we define the extended ALM routing problem and its heuristic algorithm ExCT+, to optimize the effectiveness of the multihome network in ALM communications by selecting multihomed hosts and connections in the ALM routing tree simultaneously. For their evaluations, we construct a network simulation model named MINET (multiple-ISP network simulator), where the topology is composed of multiple ISP backbone networks with IX connections, and the network traffic is generated by following the M/M/1 queuing process. The simulation results using MINET verify the effectiveness of our algorithms.</p

An Eye-Contour Extraction Algorithm from Face Image usingDeformable Template Matching

A variety of studies on face components such as eyes, lips, noses, and teeth have been proceeding in medicine, psychology, biometrics authentication, and other areas. In this paper, we present an algorithm of extracting eye contours from a face image using the deformable template matching method. Our template for an eye contour is composed of three quadratic functions for the perimeter and one circle for the pupil. In our algorithm, a digital color face image is rst converted to a binary image of representing eyes, after the region around eyes is identied on the face image by using hues and values of the color image. Then, parameters in the template are optimized by a local search method with a tabu period and a hill-climbing, so as to t the template to the eye contour in the binary image. The accuracy of our algorithm is evaluated through sample face images of students. In addition, the application of our proposal to eye shape indices is investigated in a face image database "HOIP", where recognizable dierence exists in index distributions between males and females

Optical-drop wavelength assignment problem for wavelength reuse in WDM ring metropolitan area networks

This paper presents a formulation of the optical-drop wavelength assignment problem (ODWAP) and its heuristic algorithm for WDM ring networks. The wavelength-division multiplexing (WDM) technology has been popular in communication societies for providing very large communication bands by multiple lightpaths with different wavelengths on a single optical fiber. Particularly, a double-ring optical network architecture based on the packet-over-WDM technology such as the HORNET architecture has been studied as a next generation platform for metropolitan area networks (MANs). Each node in this architecture is equipped with a wavelength-fixed optical-drop and a tunable transmitter so that a lightpath can be established between any pair of nodes without wavelength conversions. In this paper, we formulate ODWAP for efficient wavelength reuse under heterogeneous traffic in this network. Then, we propose a simple heuristic algorithm for ODWAP. Through extensive simulations, we demonstrate the effectiveness of our approach in reducing waiting times for packet transmissions when a small number of wavelengths are available to retain the network cost for MANs

Near-Optimal Detection for Binary Tardos Code by Estimating Collusion Strategy

A previously proposed optimal detector for bias-based fingerprinting codes such as Tardos and Nuida requires two kinds of important information: the number of colluders and the collusion strategy used to generate the pirated codeword. An estimator has now been derived for these two parameters. The bias in the pirated codeword is measured by observing the number of zeros and ones and compared with possible bias patterns calculated using information about the collusion strategy and number of colluders. Computer simulation demonstrated that the collusion strategy and number of colluders can be estimated with high probability and that the traceability of a detector using the proposed estimator is extremely close to being optimal

A proposal of calligraphy learning assistant system with letter portion practice function using projection mapping

Purpose For several decades, calligraphy has been popular among people in Japan, China, and even in the world. Traditionally, a teacher teaches how to write letters on a paper with a brush, and a student will imitate them by referring to the model letters. However, if a teacher is not available, this method will not be applicable either. This study aims to propose a calligraphy learning assistant system (CLAS) using projection mapping, which allows a student to learn calligraphy by him/herself. Design/methodology/approach By following the letter writing video of a teacher that is directly projected on the paper, a student is able to learn the stroke order and writing speed in addition to the letter shape. Moreover, the letter portion practice function is incorporated in CLAS to allow a learner to repeat practicing hard portions of each letter. Findings For evaluations, the authors implemented CLAS using Raspberry Pi and open-source software and asked students to use it. The results confirmed that CLAS is effective in improving calligraphy skills of novice students. Originality/value With CLAS, a student can practice calligraphy using a conventional brush, ink and paper at a desk while looking at the model letter writing of a teacher projected on the paper using projection mapping

A global routing technique for wave-steered design methodology

Wave-Steering is a new circuit design methodology to realize high throughput circuits by embedding layout friendly structures in silicon. Latches guarantee correct signal arrival times at the input of synthesized modules and maintain the high throughput of operation. This paper presents a global routing technique for networks of wave-steered blocks. Latches can be distributed along interconnects. Their number depends on net topologies and signal ordering at the inputs of wave steered blocks. here, we route nets using Steiner tree heuristics and determine signal ordering and latch positions on interconnect. The problem of total latch number minimization is solved using SAT formulation. Experimental results on benchmark circuits show the efficiency of our technique. We achieve on average a 40% latch reduction at minimum latency over un-optimized circuits operating at 250 MHz in 0.25 &#956;m CMOS technology</p