Evaluation of water film by reynolds' equation in deep drawing using high-pressured water jet

The authors had proposed a deep drawing method using high-pressured jet waters as lubricant. This method aimed to suppress the usage of oil or other chemical lubricants, which might require some additional processes for lubricant removal and become a nuisance in environment. The conditions had been determined through trial and error approach without knowing water behaviors as lubricant. As a result, some scars and dimples were observed on the surface of deformed cup. In the present paper, a numerical model was composed for the evaluation of the water behaviors as lubricant. Darcy-Weisbach equation was used for evaluation of pressure drop between nozzle exit and pump, while Reynolds' equation was used for the thin film of fluid between the die and blank. The data of blank deformation in FEM was considered for the determination of the thickness distribution of the fluid film. The characteristics of the water were evaluated by the composed numerical method, and the results were used for examination of lubrication characteristics in experiments

Prevention of drowsy driving by means of warning sound

Traffic accidents occur due to inattentive driving such as drowsy driving. A variety of support systems that make an attempt to prevent inattentive driving are under development. The development of a system to prevent drowsy driving using auditory or tactile alarm system is undertaken. It is essential to detect the low arousal state and warn drivers of such a state so that drowsy can be prevented. EEG (Electroencephalography) was used to evaluate how an arousal level degraded with time for eight participants under a low arousal level. Mean power frequency (MPF) was calculated to evaluate an arousal level. The value of MPF was compared between high and low arousal levels. The difference of arousal effect among four warning sounds was examined. As a result, there was no significant difference of arousal effect among four alarm sounds. The alarm sound was found to temporarily heighten participants' arousal level

An extrusion method of tube with spiral inner fins by utilizing generation of spiral outer fins/grooves

This paper presents a new extrusion method for fabrication of a tube with spiral inner fins. The spiral fins are formed by utilizing the generation of spiral outer fins or grooves, which drive the metal to circumferentially move with twist deformation. The effect of the outer fins/grooves is examined for realizing the circumferential metal flow. The position of the mandrel has an ability to flexibly control the spiral angle. This method would drastically enhance the productivity and reduce the manufacturing cost, as the tube would be manufactured directly from a billet through only one process

Evaluation of Automotive Control-Display System by means of MentalWorkload

The effects of age, task difficulty on performance and mental workload were discussed in order to provide design guideline of automobile display that is friendly to older adults from the viewpoints of mental attention, speed and accuracy. A dual-task experiment was conducted in which the primary task was first order tracking. The secondary tasks included selection of function (easy condition), and control of an air conditioner, the operation of a radio, and the operation of a CD/MD (difficult condition), by means of a steering wheel mounted switch. The display was arranged in front of a participant. Age affected the performance measures and heart rate variability (HRV). As for the young adults, the task completion time did not differ significantly among easy and difficult (one-, two-, and three-layered) conditions. The performance of older adults was affected by task difficulty. The HRV measures such as CV (coefficient of variance) and RRV8-3 during the task showed different tendency between young and older adults. As for the young group, the HRV measures did not differ significantly between the four task levels (easy, one-, two-, and three-layered). This confirmed that the task difficulty did not induce different mental workload to young adults. On the other hand, as for the older adults, the HRV measures tended to increase with the increase of task difficulty. Although it appears that mental workload was lessened with the increase of task difficulty, such an interpretation was contradictory to the results on performance. This phenomenon was interpreted that the difficult task condition was overloaded for older adults, and was beyond the limit of mental effort. Based on the results, it could be concluded that the difficult task condition is not proper for older adults

Effectiveness of the menu selection method for eye-gaze input system - Comparison between young and older adults -

Although the opportunity of older adults to use personal computer is increased more and more, the operation of a personal computer with a mouse is very annoying for older adults who cannot move his or her arm smoothly and effectively due to declined motor function. An attempt to move a cursor by an eye-gaze input system has been carried out as one solution to this problem. Until now, a menu selection method suitable for an eye-gaze input system has not been clarified. In this study, an effective menu selection for the eye-gaze input system was identified as a basic design parameter to develop a Web browser using an eye-gaze input system. Concretely, a menu selection method, that is, improved quick glance menu selection (I-QGMS) was proposed. The effectiveness was evaluated by means of the pointing accuracy, the pointing time, and the psychological rating on usability. On the basis of the evaluation experiment, the proposed I-QGMS was found to be effective especially for older adults

Usability of Site Map in Web Design – Design of Site Map that is Friendly to Older Adults-

The information or data for Web page design that is useful, in particular, to older adults was provided in this study. The proper design of site map is necessary to enhance the usability and reduce the number of getting lost in Web navigation especially for older adults. However, no design guideline on what site map is proper exists. The usability of six types of site maps was compared as a function of age. The six types of site maps included (1) vertical tree type, (2) horizontal tree type (A), (3) horizontal tree type (B), (4) table type, (5) radial type, and (6) itemized type. The usability was evaluated using search time, subjective rating of usability, and eye movement characteristics (fixation duration and fixation number). The age affected the evaluation measures. The horizontal type (B) was found to lead to faster search time and fewer fixation numbers. Moreover, this type of site map was found to make the difference of search time, fixation number, and fixation duration between young and older adults smaller. The result indicated that the vertical arrangement of site map, especially horizontal type (B) was proper for both young and older adults, and this should be incorporated into the Web page design guidelines. The results can be utilized as a universal design guideline for providing a site map that is friendly to both young and older adults

Hadronic decays of B→a1(1260)b1(1235)B \to a_1(1260) b_1(1235) in the perturbative QCD approach

We calculate the branching ratios and polarization fractions of the $B \to a_1 b_1$ decays in the perturbative QCD(pQCD) approach at leading order, where $a_1$($b_1$) stands for the axial-vector $a_1(1260)[b_1(1235)]$ state. By combining the phenomenological analyses with the perturbative calculations, we find the following results: (a) the large decay rates around $10^{-5}$ to $10^{-6}$ of the $B \to a_1 b_1$ decays dominated by the longitudinal polarization(except for the $B^+ \to b_1^+ a_1^0$ mode) are predicted and basically consistent with those in the QCD factorization(QCDF) within errors, which are expected to be tested by the Large Hadron Collider and Belle-II experiments. The large $B^0 \to a_1^0 b_1^0$ branching ratio could provide hints to help explore the mechanism of the color-suppressed decays. (b) the rather different QCD behaviors between the $a_1$ and $b_1$ mesons result in the destructive(constructive) contributions in the nonfactorizable spectator diagrams with $a_1(b_1)$ emission. Therefore, an interesting pattern of the branching ratios appears for the color-suppressed $B^0 \to a_1^0 a_1^0, a_1^0 b_1^0,$ and $b_1^0 b_1^0$ modes in the pQCD approach, $Br(B^0 \to b_1^0 b_1^0) > Br(B^0 \to a_1^0 b_1^0) \gtrsim Br(B^0 \to a_1^0 a_1^0)$, which is different from $Br(B^0 \to b_1^0 b_1^0) \sim Br(B^0 \to a_1^0 b_1^0) \gtrsim Br(B^0 \to a_1^0 a_1^0)$ in the QCDF and would be verified at future experiments. (c) the large naive factorization breaking effects are observed in these $B \to a_1 b_1$ decays. Specifically, the large nonfactorizable spectator(weak annihilation) amplitudes contribute to the $B^0 \to b_1^+ a_1^-(B^+ \to a_1^+ b_1^0\; {\rm and}\; B^+ \to b_1^+ a_1^0)$ mode(s), which demand confirmations via the precise measurements.Comment: 13 pages, 1 figure, 5 tables, revtex fil

Effects of location of information presentation in pedestrian detection system on visibility and performance

A few pedestrian warning systems for automobiles are in practical use. It has not been clarified where is best suited for the location of pedestrian information presentation. The most effective location of information presentation in pedestrian detection system was investigated. In other words, the location that assured the fastest cognition of pedestrian information was clarified. The locations of information presentation in pedestrian detection system were front glass, front display of cockpit module, and left side display of cockpit module (like car navigation system). The participants were required to pay attention to the predetermined front area as well as the randomly presented pedestrian information while carrying out a virtual driving task (tracking task) and a secondary switch pressing task such as selection of wiper function. We also investigated the effect of alarm sound presented to the participants together with the visual pedestrian information on the cognition time of pedestrian information. As a result, the front glass was most suitable for the presentation of pedestrian information. The presentation of pedestrian information to the front glass led to high visibility and faster pedestrian cognition time