Compensation for position‐dependent mechanical resonances in head‐positioning control of hard disk drives

We propose a compensation method for position‐dependent mechanical resonances in head‐positioning control system of hard disk drives (HDDs). To realize high‐accuracy head‐positioning control, it is important to compensate for the mechanical resonances in the head‐positioning control system. The some mechanical resonance characteristics depend on the magnetic head's location. In conventional design method, a notch filter must be designed to compensate for the mechanical resonances at any magnetic head location. The disadvantage is that phase lag caused by the notch filter worsens the stability of the head‐positioning control system. To overcome this disadvantage, we propose a magnetic head‐position‐dependent notch filter to compensate for the position‐dependent mechanical resonances in the head‐positioning control system. The simulation results in HDD benchmark model show that the proposed method can decrease the phase lag caused by the notch filter. That is, the proposed method can improve the stability compared to the conventional method. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Improved 40-inch plasma display for wall-hanging HDTV receiver

A new 40-inch-diagonal color dc plasma display panel (cell pitch: 0.65 mm, 800×1340 cells) with both a resistor-in-cell structure and a phosphor screen on the side wall and bottom of the cell has been developed through the improvement on the large-area panel fabrication technologies. Stable HDTV pictures have been experimentally reproduced on a compact display using the new panel and pulse memory drive circuits. The peak white luminance is 150 cd/m². The lifetime of the 40-inch panel is expected to be over 30,000 hours, judging from the results obtained using a medium-sized panel under the same conditions     

Diabetes associated with a novel 3264 mitochondrial tRNA(Leu)(UUR) mutation

OBJECTIVE: To present a novel mitochondrial DNA mutation in a diabetic family RESEARCH DESIGN AND METHODS: The proband was a 64-year-old man. In the family, diabetes was maternally inherited. He had diabetes, cerebellar ataxia, cervical lipoma, hearing loss, olfactory dysfunction, ophthalmoplegia, and facial nerve bilateral palsy. On examination, early insulin secretion was blunted, and the M value on glucose clamp test was low. In muscle, ragged red fibers were not found. T-to-C mutation at position 3264 was detected in the proband (0.5% mutant DNAs in leukocyte and 30% in muscle), but was not detected in 201 normal individuals. RESULTS: Heteroplasmy of mutation, maternal inheritance of diabetes, and symptoms related to mitochondrial dysfunction suggest the pathogenecity of this 3264 mutation. As for diabetes etiology, both impaired insulin secretion and decreased insulin sensitivity seem to be important. In phenotypic characteristics, the combination of cerebellar ataxia and lipoma is a symptom sometimes found in myoclonic epilepsy and ragged red fibers (MERRFs). Ophthamoplegia is a symptom of chronic progressive external ophthalmoplegia (CPEO). These suggest that our proband had phenotypic overlap with MERRF and CPEO. Conversely, facial nerve bilateral palsy is a rare finding. The pictures that focused on his cranial nerves were thus unique, suggesting the heterogeneity of mitochondrial DNA (mtDNA)-related diabetes. CONCLUSIONS: A novel 3264 mitochondrial DNA mutation in diabetes gives new insight to the etiology of mitochondrial diabetes. Its pathogenecity supports the belief that the tRNA(Leu)(UUR) gene is an etiological hot spot of mitochondrial diseases.     

A 5-V-only operation 0.6-μm flash EEPROM with row decoder schemein triple-well structure

An experimental 4-Mb flash EEPROM has been developed based on 0.6-μm triple-well CMOS technology in order to establish circuit technology for high-density flash memories. A cell size of 2.0×1.8 μm² has been achieved by using a negative-gate-biased source erase scheme and a self-aligned source (SAS) process technology. A newly developed row decoder with a triple-well structure has been realized in accordance with its small cell size. The source voltage during the erase operation was reduced by applying a negative voltage to the word line, which results in a 5-V-only operation. The chip size of the 4-Mb flash EEPROM is 8.11×6.95 mm², and the estimated chip size of a 16-Mb flash EEPROM is 98.4 mm² by using the minimal cell size (2.0×10 μm²)     

Beta2-glycoprotein I is necessary to inhibit protein C activity by monoclonal anticardiolipin antibodies

OBJECTIVE: To clarify mechanisms of the thrombosis associated with anticardiolipin antibodies (aCL), we examined the effects on activated protein C (APC) of monoclonal aCL and beta2-glycoprotein I (beta2GPI), which is required for formation of the epitopes of aCL. METHODS: We developed the chromogenic assay, in which the degradation of coagulation factor Va by APC is reflected in the reduced generation of thrombin from prothrombin, using soybean trypsin inhibitor to inhibit APC. APC activities were measured in the presence and absence of 3.4 microM beta2GPI and/or 2.5 microg/ml of IgM monoclonal aCL (EY2C9 and EY1C8) established from peripheral blood lymphocytes obtained from a patient with aCL. RESULTS: Without APC, the formed thrombin activity decreased by the addition of 3.4 microM beta2GPI. When 12.8 nM APC was added, beta2GPI partially reversed the APC-induced inhibition of thrombin generation in a concentration-dependent manner. With 3.4 microM beta2GPI, the thrombin generation in monoclonal aCL (2.5 microg/ml) decreased to 77.1-80.2% by the addition of 12.8 nM APC, but the values were above that in the control IgM (72.7%). Without beta2GPI, the APC activity was unaffected by the addition of monoclonal aCL. CONCLUSION: Beta2-glycoprotein I exhibits procoagulant activity by inhibiting APC activity and anticoagulant activity by inhibiting thrombin generation. Any further inhibition of APC activity was caused by monoclonal aCL and only in the presence of beta2GPI.     

Using multiple data sources to get closer insights into user cost and task performance

This pilot study explores the use of combining multiple data sources (subjective, physical, physiological, and eye tracking) in understanding user cost and behavior. Specifically, we show the efficacy of such objective measurements as heart rate variability (HRV), and pupillary response in evaluating user cost in game environments, along with subjective techniques, and investigate eye and hand behavior at various levels of user cost. In addition, a method for evaluating task performance at the micro-level is developed by combining eye and hand data. Four findings indicate the great potential value of combining multiple data sources to evaluate interaction: first, spectral analysis of HRV in the low frequency band shows significant sensitivity to changes in user cost, modulated by game difficulty—the result is consistent with subjective ratings, but pupillary response fails to accord with user cost in this game environment; second, eye saccades seem to be more sensitive to user cost changes than eye fixation number and duration, or scanpath length; third, a composite index based on eye and hand movements is developed, and it shows more sensitivity to user cost changes than a single eye or hand measurement; finally, timeline analysis of the ratio of eye fixations to mouse clicks demonstrates task performance changes and learning effects over time. We conclude that combining multiple data sources has a valuable role in human–computer interaction (HCI) evaluation and design.     

Optimization of word-line booster circuits for low-voltage flashmemories

Two word-line booster circuits, which output a word-line voltage for reading dash memory data, are analyzed and optimized. A capacitor-switched booster circuit outputs a voltage higher than the supply voltage by switching the connection state of one of more boosting capacitors with the load capacitor from parallel to series. The optimum number of capacitors and capacitance per boosting capacitor are obtained as a function of the voltage ratio of the required high voltage to the supply voltage. The operation current consumed by the boosting operation is also analytically derived. In addition, another booster circuit-Dickson charge-pump circuit-is optimized under the condition to maximize the output current at a high word-line voltage. Characteristics of the booster circuits are compared, and the selection of booster circuit for low-voltage flash memory is discussed     

Resonant tunnelling delta sigma modulator suitable for high-speed operation

A resonant tunnelling logic gate, monostable-bistable transition logic element (MOBILE), was used to test high frequency operation of the /spl Delta//spl Sigma/ modulator based on a frequency modulated intermediate signal. This /spl Delta//spl Sigma/ modulator has no feedback loop and is promising for high-speed operation. Good noise shaping characteristics over four decades were measured. This ideal noise shaping demonstrated that the MOBILE can work as an ideal quantiser.