The concealed information test (CIT) is a psychophysiological method for detecting a suspect's knowledge about a crime by comparing autonomic responses between crime-relevant and crime-irrelevant stimuli. Although the autonomic-based CIT has been widely used for criminal investigations in Japan, the cognitive processes underlying the test remain unclear. In order to examine this, we recorded event-related potentials (ERPs) from 128 scalp sites during an autonomic-based CIT. We asked 20 participants to steal an item and then conducted an autonomic-based CIT about the stolen item. A temporal-spatial principal component analysis revealed that three ERP components differed significantly between crime-relevant and crime-irrelevant items. The first component was a central-dominant negative component that peaked at 180 ms (N2). The second component was a parietal-dominant positive component that peaked at 461 ms (P300), which may be affected by the personal meaning of the crime-relevant item. The third component was an occipital-dominant positive component that occurred at 797 ms (positive slow wave), which may reflect an additional process after identifying the crime-relevant item. The present results suggest that in an autonomic-based CIT, a participant discriminates a crime-relevant item from crime-irrelevant items in around 200 ms after item onset and then performs an additional process to the indentified crime-relevant items.

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When two target stimuli (T1 and T2) are embedded in a rapid serial visual presentation (RSVP) stream of distractors and presented at variable stimulus onset asynchronies (SOAs), detection of T2 is impaired at SOAs of less than 600 ms. This phenomenon is called attentional blink. However, the attentional blink is often observed only if T2 is masked by a trailing stimulus. In the present study, T2 was the last item in the stream, and therefore unmasked. As a result, the typical attentional blink was not observed and the amplitude of the P3 component of the event-related potential (ERP) time-locked to T2 onset did not decrease. However, P3 latency was delayed with respect to the length of SOA between T1 and T2. Many studies have reported that the decrease in accuracy of detecting T2 in the attentional blink paradigm recovers as SOA of targets increases. Our results suggest that the brain process reflected in the P3 component is closely related to the strength of the attentional blink deficit.

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To investigate if the reaction time effect from an imagery task was due to behavioral control by tacit knowledge, we estimated ERP P3, the peak latency of which reflects stimulus classification speed. Participants visualized the uppercase letter on grids corresponding to a lowercase letter beneath them, and pressed a button only for the infrequent target trials, in which an "X" probe mark in any cell fell on the visualized letter. Half of these target trials were labeled "early" because the probe placed on a segment drawn early in the order to be drawn, and the other half were "late". Not only RT, but P3 latency were modulated by the required stimulus classification speed for the corresponding imagery representation. The result indicates that reaction time for the imagery task reflects cognitive decision based on the spatial property of imagery representation.

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The purpose of this study was to investigate human attention and auditory processing as indexed by event-related potential (ERP) mismatch negativity (MMN). MMN was recorded during gaps in rhythmic, repetitive sound. A hemispheric asymmetry was observed for the early negativity but not MMN amplitude. LORETA analysis findings support the assumption that the change detection signal generated by the auditory cortex triggers frontal mechanisms. We conclude that the right hemispheric response to rhythm change triggers attention-switching processes mediated via the ACC.

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Sleep and awakening are critical issues for people under high levels of stress in modern society. However, only a few studies on the effects of music on awakening have been conducted; thus, we focused on the effect of music on comfortable awakening in humans. This paper is the first to analyze the comfort of forced awakening relative to music and the brain. This is an analytical and observational study: a descriptive study of awakening from naps with music using three psychological tests. Ten healthy subjects (5 men and 5 women) participated in this experiment. Quantitative analyses were conducted on the subjects' feelings when awakened from a nap either with music or with an alarm tone. The music changes with time: We change width of the frequency to output. Participants were awakened after naps of 30, 60, 90 and 120 minutes for a total of 8 times overnight. Subjective feelings just after awakening were measured with three psychological questionnaires. The differences between the subjective data with music and with an alarm tone were calculated and analyzed. The results indicate that awakening with music was more comfortable than awakening with an alarm tone. Additionally, differences in comfort levels between awakening with music and awakening with an alarm tone were smaller at 30 and 90 minutes than at 60 and 120 minutes, suggesting the effects of the circadian rhythms.

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In this study, we examine a supporting method for making recipe for a measure against metabolic syndrome. We use existing recipes to produce new recipes as a countermeasure against metabolic syndrome. Some ingredients with fewer calories are used in new recipes instead of original ingredients in existing recipes as a countermeasure against metabolic syndrome. We therefore produce an ingredient thesaurus, which is useful to support making of new recipes as a measure against metabolic syndrome. We assess the effectiveness of the proposed method using experiments.

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Effective diagnostic capabilities and good drilling technique are both vital skills for dentists. Typical training approaches include the use of synthetic replica teeth or real teeth extracted from patients. Both present challenges with respect to cost and difficulty of creating representations of specific pathologies. Our research focuses on developing interactive computer-based simulations to help address these issues. We have created a prototype dental drilling training system that demonstrates a number of key technical components, and we have begun the process of validating the educational effectiveness of the simulator by running a pilot user study. The aim of the pilot study is to evaluate our experimental design and to identify potential improvements to the system design and experimental procedure in preparation for a full-sized user study. Method: We have run a user study in which we compared the performance of simulator-trained students to that of students trained using real-world drills. All participants were first or second year undergraduate dental students at Fukuoka Dental College with no prior experience in dental drilling. Results: Over the course of multiple training sessions, practice time decreased sharply for participants in the real-world training group, while it increased for those in the simulation group, indicating increased engagement with the task in the simulation group. Participants in the simulation group also showed a large jump in performance after the first session. This jump can be attributed to participants overcoming their initial unfamiliarity with the virtual reality system. Performance of the two groups on the final test was very close. Conclusion: The results of the experiment are encouraging, in that the simulation group experienced no recognizable negative training effects and performed on par or better than the real-world training group. The pilot study also pointed out a number of areas for improvement in the simulation, such as a more intuitive display system and better replication of the true hardness of teeth within the simulation, which we have since incorporated into the program. We will begin a modified and expanded version of the same study based on the experience gained from the pilot study.

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In this paper we address the problem of Software-MCU assignment in car electronic system design. This is a difficult optimization problem due to complex characteristics of the car electronic system; further, designer preferences make the problem more difficult. In order to solve this combinatorial optimization problem we propose a method which is based on the Lagrangian method. Experimental results show that the search can effectively find the feasible solutions. We also introduce short and long term memories to the Lagrangian method. There are several ways of integrating the short and long term memories. We examine these ways of integration in the experiments, and decide the most effective one. When we use this effective integration method, we can improve the efficiency of the Lagrangian method further.

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In order to examine the accidents involving organic solvents from 1995 to 2006 in Japan, all the cases were classified into 3 types of industry (construction, manufacturing, and other service industries), 12 types of work, 13 types of causes, and 5 types of unified causes. The relationship among the types of industry, the types of work, and the causes of the accidents were analyzed by the use of the Kruskal's multi-dimensional scaling method. All the analytical results were presented on a two-dimensional distribution in which both the abscissas and the ordinates were originally defined. All the data allocated in the distribution were classified into 3 or 4 groups in order to analyze the background information of the organic solvent accidents. We found that Kruskal's multi-dimensional scaling analysis is suitable for revealing the essence of a small number of miscellaneous cases, such as organic solvent accidents.

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Phonocardiography diagnosis can be improved by modern techniques of signal processing. It is shown that the wavelet transform provides enough features of the PCG signals that will help clinics to obtain qualitative and quantitative measurements of the time-frequency PCG signal characteristics and consequently aid to diagnosis. Abnormal heartbeat sounds may contain, in addition to the first and second sounds, Si and S2, murmurs and aberrations caused by different pathological conditions of the cardiovascular system. This work investigates the analysis of the heartbeat cardiac sounds (or the phonocardiogram signal) using the time-frequency analysis by using the continuous version of the wavelet transforms method. We show here a comparative study of normal and abnormal heart sounds (or phonocardiogram signals), whose scalograms exhibit noticeable morphological differences in terms of duration and spectral composition of sounds. These differences suggest that the cochlear-wavelet-based scalograms can become an interesting approach to design automatic diagnosis systems.

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A chemical analysis for the flavor of wines is attempted by three methods, i.e., GC/MS and SPME. At first, the ability of GC/MS and ZB-WAX column are confirmed by using 4 mixed similar chemical compounds. These are clearly separated and identified by GC/MS. Secondly, some fragrances are analyzed by using SPME for absorption of volatile compounds. This kit effectively works, and it is revealed that same or similar chemical compounds are contained among different samples. This result is supposed that a discriminative compound performs as an element of an aroma.

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This paper proposes queueing network models of cellular mobile communications networks for analyzing the soft capacity peculiar to Code Division Multiple Accesses (CDMA). I formulated these models as Jackson networks with multiple classes and state-dependent transition rates, that is to say, BCMP networks. I derived the product form of equilibrium distribution. As the performance measures, I obtain the explicit probabilities of call losses and handover blockings.

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This paper presents integrated physiological interaction simulation for a large-scale circulatory system which combines macro and micro models concerning with heart functions. The macro model is composed of physiological modules such as neural activity, hormonal adjustment, and body temperature control, and provides a mathematical representation of comprehensive knowledge of circulation physiology. The micro model, on the other hand, uses differential equations to describe hemodynamics with the heart as a pump, and calculates the heart pulsations in millisecond time steps. An electrical circuit model is constructed for the systemic and pulmonary circulatory systems, in which the time-varying elasticity of the ventricular muscle corresponds to a variable capacitor. By connecting the macro and micro models through common variables, a simulation which combines macroscopic and microscopic hemodynamics is produced Namely the investigation of the response of the pulsatile blood flow under various parameter conditions in the human body becomes possible.

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