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1.
Roope Kaivola Katherine Kohatsu 《International Journal on Software Tools for Technology Transfer (STTT)》2003,4(3):323-334
We examine the challenges presented by large-scale formal verification of industrial-size circuits, based on our experiences
in verifying the class of all micro-operations executing on the floating-point division and square root unit of the Intel
IA-32 Pentium?4 microprocessor. The verification methodology is based on combining human-guided mechanised theorem-proving
with low-level steps verified by fully automated model-checking. A key observation in the work is the need to explicitly address
the issues of proof design and proof engineering, i.e., the process of creating proofs and the craft of structuring and formulating
them, as concerns on their own right.
Published online: 19 November 2002 相似文献
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Tatiana G. Evreinova Grigori Evreinov Roope Raisamo Leena K. Vesterinen 《Universal Access in the Information Society》2008,7(1-2):93-102
Blind and visually impaired students need special educational and developmental tools to allow them to interact with graphic
entities on PDA and desktop platforms. In previous research, stylus movements regarding the hidden graph were sonified with
three directional-predictive sound (DPS) signals, taking into account an exploration behavior and the concept of the capture
radius. The results indicated that the scanpaths were by 24–40% shorter in length and task completion times decreased by 20–25%.
The goal of the study presented in this paper was to measure and compare the subjective performance recorded with directional-predictive
vibrations (DPV) regarding the subjective performance achieved when the hidden graphic images were explored with DPS. The
study also aimed to find out which kind of feedback cues would require less cognitive efforts in interpreting their meaning.
The prototype of vibro-tactile pen with embedded vibration motor was used to produce DPV instead of sounds. The performance
of eight blindfolded subjects was investigated in terms of the number of both feedbacks used and the time spent to complete
non-visual inspection of the hidden graphs. There was a statistically significant difference between the average number of
DPS and vibrations and task completion time taken by the players to discover the features of hidden graphs being explored
with different capture radius. The experimental findings confirmed the beneficial use of DPS signals in the task when cross-modal
coordination should benefit the user in the absence of visual information when compared with DPV patterns. 相似文献
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Tatiana V. Evreinova Grigori Evreinov Roope Raisamo 《Universal Access in the Information Society》2008,7(3):129-144
This paper presents the results of a comparative study of user input with a camera-joystick and a manual joystick used in
a target acquisition task when neither targets nor pointer could be perceived visually. The camera-joystick is an input technique
in which each on-screen item is accessible from the center with a predefined vector of head motion. Absolute pointing was
implemented with an acceleration factor of 1.7 and a moving average on 5 detected head positions. The underlying assumption
was that, in order to provide a robust input for blind users, the interaction technique has to be based on perceptually well-discriminated
human movements, which compose a basic framework of an accessible virtual workspace demanding minimum external auxiliary cues.
The target spots, having a diameter of 35 mm and a distance between the centers of adjacent spots of 60 mm, were arranged
in a rectangular grid of 5 rows by 5 columns. The targets were captured from a distance of 600 mm. The results have shown
that the camera input is a promising technique for non-visual human–computer interaction. The subjects demonstrated, more
than twice, better performance in the target acquisition task with the camera-joystick versus the manual joystick. All the
participants reported that the camera-joystick was a robust and preferable input technique when visual information was not
available. Blind interaction techniques could be significantly further improved allowing a user-dependent activation of the
navigational cues to better coordinate feedbacks with exploratory behavior. 相似文献
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Jani Heikkinen Jussi Rantala Thomas Olsson Roope Raisamo Jani Lylykangas Jukka Raisamo Veikko Surakka Teemu Ahmaniemi 《Journal of Visual Languages and Computing》2009,20(5):287-304
Haptic gestures and sensations through the sense of touch are currently unavailable in remote communication. There are two main reasons for this: good quality haptic technology has not been widely available and knowledge on the use of this technology is limited. To address these challenges, we studied how users would like to, and managed to create spatial haptic information by gesturing. Two separate scenario-based experiments were carried out: an observation study without technological limitations, and a study on gesturing with a functional prototype with haptic actuators. The first study found three different use strategies for the device. The most common gestures were shaking, smoothing and tapping. Multimodality was requested to create the context for the communication and to aid the interpretation of haptic stimuli. The second study showed that users were able to utilize spatiality in haptic messages (e.g., forward–backward gesture for agreement). However, challenges remain in presenting more complex information via remote haptic communication. The results give guidance for communication activities that are usable in spatial haptic communication, and how to make it possible to enable this form of communication in reality. 相似文献
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Christopher Boyd Roope Vehkalahti Olav Tirkkonen 《International Journal of Wireless Information Networks》2018,25(4):422-433
Combinatorial code designs (CCDs) are proposed as a means for achieving ultra-reliability in the random access channel. In contrast to traditional access protocols that use random repetition coding, we show that by uniquely allocating repetition patterns to users, successful reception may be guaranteed up to a number of simultaneously active users in small frame sizes. Such codes are particularly robust in the low activity region where mission-critical machine-type communication is expected to operate. We also present deterministic codes designed to work in conjunction with successive interference cancellation to further improve reliability. The optimal IC code for frames of 5 access slots is given. Unlike slotted ALOHA, it is shown to limit packet losses to well below the ultra-reliability threshold (10?5). These error performance gains come at the cost of a strict limitation on the supported user population (11 users in the case of 5 slots). We therefore consider larger frames of 24 slots, and analyse heuristic, low-complexity CCDs with fixed repetition factors that support up to 2024 users. While these are sub-optimal IC codes, significant gains are still observed compared to random codes. 相似文献
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Rami Saarinen Janne Järvi Roope Raisamo Eva Tuominen Marjatta Kangassalo Kari Peltola Jouni Salo 《Virtual Reality》2006,9(2-3):108-117
Visually impaired children have a great disadvantage in the modern society since their ability to use modern computer technology is limited due to inappropriate user interfaces. The aim of the work presented in this paper was to develop a multimodal software architecture and applications to support learning of visually impaired children. The software architecture is based on software agents, and has specific support for visual, auditory and haptic interaction. It has been used successfully with different groups of 7-8 year-old and 12 year-old visually impaired children. In this paper we discuss the enabling software technology and interaction techniques aimed to realize our goal and our experiences in the actual use of the system. 相似文献
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Tuck L Astala R Reid JW Sayer M Stott MJ 《Journal of materials science. Materials in medicine》2008,19(2):917-927
Ultrasonically accelerated dissolution of multiphase silicon stabilized tricalcium phosphate powders in water or Earle’s balanced
salt solution transforms the powders into needle-like calcium deficient apatite crystals with the c-axis (001) oriented along
the needle. Ion exchange with the solution occurs primarily in the first hours of immersion. The transformation is driven
by an interaction between the crystal surface and adsorbed water leading to the growth of crystallites which have the most
stable surface configuration. First principles calculations of the surface energies of various hydroxyapatite surfaces with
and without adsorbed water shows that depending on the ion concentrations in the fluid that determine the chemical potential
of tricalcium phosphate, either Ca-rich (010) or stoichiometric (001) layers are the dominant surfaces. The higher the chemical
potential, the more elongated in the (001) direction the crystallites become to minimize the total surface energy. The loss
of a calcium Ca2+ compensated by the addition of two H+ is strongly favoured energetically on the (001) and Ca-rich (010) surfaces. A high concentration of excess Si at grain boundaries
may be partly responsible for the rapid transformation of multiphase Si-TCP. 相似文献
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Mäkinen E Raisamo R 《IEEE transactions on pattern analysis and machine intelligence》2008,30(3):541-547
We present a systematic study on gender classification with automatically detected and aligned faces. We experimented with 120 combinations of automatic face detection, face alignment and gender classification. One of the findings was that the automatic face alignment methods did not increase the gender classification rates. However, manual alignment increased classification rates a little, which suggests that automatic alignment would be useful when the alignment methods are further improved. We also found that the gender classification methods performed almost equally well with different input image sizes. In any case, the best classification rate was achieved with a support vector machine. A neural network and Adaboost achieved almost as good classification rates as the support vector machine and could be used in applications where classification speed is considered more important than the best possible classification accuracy. 相似文献
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