Search

Acute subdural hematoma (ASDH) sometimes occurred in judo because of the bridging veins' failure by rotation of the brain in the skull. However, the relationship between intracranial behaviour and the motion of the body on occiput impact has not yet been clarified. In this study, we developed an intracranial mechanical model based on multibody dynamics and compared it with experimental results. The results show the importance of modelling bridging veins and cerebral spinal fluid to the relative displacement between brain and skull. The proposed model will contribute to accident analyses or the optimum design of supporting devices.

Switching ability for infrared-light (IR) of commercial glass is of great interest for realizing practical smart windows which enable energy savings. In this article, we report on highly oriented growth of vanadium dioxide (VO2) films on ZnO-buffered glass substrates by means of biased reactive sputtering technique and their high switching ability for IR against temperature based on the insulator-metal transition (IMT). In addition, lower shift of transition temperature down to 55 °C was realized without deterioration of IMT properties in which resistance change nearly three orders of magnitude was kept. Shortening of in-plane V-V atoms distance through the effect of in-plane compressive stress responsible for energetic ion irradiation to biased substrate was supposed to contribute the achievement of controlled IMT temperatures. Large switching of around 50% for transmittance of IR with wavelength of 2.5 µm was realized under controlled phase transition temperatures. We emphasized that high biasing power enabled the shift of transition temperature for IR to nearly room temperature (～38 °C) by combination of the shortening of V-V distance and the oxygen defect formation, while the IMT reveals gradual change at biasing power higher than certain threshold value.

Vanadium dioxide (VO2) is a promising compound for thermochromic applications because of its insulator-metal transition (IMT) characteristic with concomitant transmittance change for infrared-light. For practical applications, we deposited VO2 thin films on transparent ZnO films on glass substrate. Growth of (010)-oriented VO2 film was obtained on c-axis oriented hexagonal ZnO layer, however, zinc vanadate (Zn2V2O7) was formed at the interface region in conventional radio-frequency magnetron sputtering at substrate temperature of 350 °C. On the other hand, (010)-oriented VO2 films were successfully grown on ZnO/glass substrates even at lower temperature of 250 °C by introducing inductively coupled plasma (ICP)-assisted sputtering, realizing steep interface between VO2 and ZnO without undesirable compounds. The VO2 films showed resistivity drop of more than two orders of magnitude together with transmittance change for infrared-light from 45 to 10% at around 70 °C. Simultaneous achievement of steep changes for both resistivity and transmittance is a milestone for practical application of VO2 films into thermochromic devices, such as smart windows and optoelectrical devices. Further, we succeeded the low temperature growth of VO2 films on conductive Al-doped ZnO (AZO) by using ICP-assisted sputtering technique. The transmittance change of VO2 on AZO/glass from 50 to 10% was observed, realizing a basis for electrically controllable intelligent optical windows.

An exponentially Increasing number of wireless-LAN (WLAN) devices In a dense environment causes a decrease in throughput owing to collisions among the devices and the lack of contiguous bandwidth. The next-generation standard of 802.11ax improves spectrum efficiency by additionally supporting 1024 (1K) QAM, OFDMA with 80+80MHz; these impose several challenges to silicon design. 1K-QAM demands extreme IQ balance with an IRR better than −50dB over a wide frequency range up to 80MHz to achieve at least −35dB RX EVM or less. Noise characteristics better than −44dBc LO integrated phase noise as well as 50dB isolation between each TRX chain are mandatory. To best make use of the essential features defined in the 11ax standard, a real-time and arbitrary spectrum-resource control capability at each access point (AP) is beneficial both in terms of further improvement in spectrum efficiency as well as communication reliability in ISM coexisting bands and legacy WLAN. Interference identification of the order of 10μe while incorporating everything into a strictly limited silicon area is key to launching the advanced unique functionality. This paper presents a fully integrated 4×4 802.11abgn/ac/ax-compliant AP transceiver SoC. The chip offers frequency-dependent IQ (FD-IQ) mismatch calibration for both amplitude and phase, low-noise TX BB and multimode LO distribution techniques, and real-time interference detection including 2.4GHz inverter-type microwave (MW) ovens.

Chromatin-enriched noncoding RNAs (ncRNAs) have emerged as key molecules in epigenetic processes by interacting with chromatin-associated proteins. Recently, protein-coding mRNA genes have been reported to be chromatin-tethered, similar with ncRNA. However, very little is known about whether chromatin-enriched mRNA is involved in the chromatin modification process. Here, we comprehensively examined chromatin-enriched RNA in squamous cell carcinoma (SQCC) cells by RNA subcellular localization analysis, which was a combination of RNA fractionation and RNA-seq. We identified 11 mRNAs as highly chromatin-enriched RNAs. Among these, we focused on the dentin matrix protein-1 (DMP-1) gene because its expression in SQCC cells has not been reported. Furthermore, we clarified that DMP-1 mRNA was retained in chromatin in its unspliced form in SQCC in vitro and in vivo. As the inhibition of the unspliced DMP-1 mRNA (unspDMP-1) expression resulted in decreased cellular proliferation in SQCC cells, we performed ChIP-qPCR to identify cell cycle-related genes whose expression was epigenetically modified by unspDMP-1, and found that the CDKN1B promoter became active in SQCC cells by inhibiting unspDMP-1 expression. This result was further validated by the increased CDKN1B gene expression in the cells treated with siRNA for unspDMP-1 and by restoration of the decreased cellular proliferation rate by simultaneously inhibiting CDKN1B expression in SQCC cells. Further, to examine whether unspDMP-1 was able to associate with the CDKN1B promoter region, SQCC cells stably expressing PP7-mCherry fusion protein were transiently transfected with the unspDMP-1 fused to 24 repeats of the PP7 RNA stem loop (unspDMP-1-24xPP7) and we found that unspDMP-1-24xPP7 was efficiently precipitated with the antibody against mCherry and was significantly enriched in the CDKN1B promoter region. Thus, unspDMP-1 is a novel chromatin-enriched RNA that epigenetically regulates cellular proliferation of SQCC.

Objective Phosphophoryn (PP) is generated from the proteolytic cleavage of dentin sialophosphoprotein (DSPP). PP which contains tandem serine/asparatic acid rich repeats (SDrr) is known to enhance dentin mineralization. The nucleotide sequences coding SDrr are identified in the DSPP genes of toothed animals and the length variations of SDrr between intra- and inter-species have been reported. However, it remains unknown about the relationship between the length variations in SDrr and the functions of PP in matrix mineralization. Design By utilizing a mammalian expression system, we generated several recombinant PP proteins (rPP) containing SDrr of different lengths and analyzed their effects on the precipitation of calcium phosphate with an in vitro gel diffusion system. Results rPP-Δ37.6 SDrr and rPP-Δ63.5 SDrr, which possessed shortened SDrr that accounted for 62.4 and 36.5% the length of SDrr in full-length rPP (rPP-full), respectively, induced the precipitation of calcium phosphate similar to that of rPP-full at the same molar concentration, whereas rPP-ΔSDrr, in which SDrr were flipped, did not. Furthermore, rPP-Δ63.5 SDrr significantly increased the accumulation of calcium compared with rPP-full at adjusted concentrations so that the same amounts of SDrr were embedded. The results of an ELISA analysis indicated that the amounts of rPP-Δ37.6 SDrr and rPP-Δ63.5 SDrr secreted from transfected cells were 5.2- and 7.1-fold greater than that of rPP-full, respectively. Conclusions The generated rPP-Δ63.5 SDrr which can be substituted for rPP-full may be a candidate for a therapeutic molecule to facilitate hard tissue generation such as reparative dentin formation.

This paper presents a fully integrated CMOS 60-GHz transceiver chipset for short-range and high-speed wireless communication. The target application of the short-range communication is less than 5-cm communication distance and more than 2-Gb/s throughput for file transfer. In order to achieve file transfer, physical (PHY) layers with error packet correction and media access control (MAC) layer with frame-exchanging function are implemented. The MAC is designed to have a high-efficiency feature due to short interval DATA/Acknowledgement (ACK) frame exchange. It is realized by fast transmitter (TX)/receiver (RX) switching. A bonding wire-based in-package antenna is adopted using a standard BGA package without any off-chip 60-GHz components. The proposed chipset is composed of two chips, an RF chip with in-package antenna, and a baseband chip including PHY and MAC layer. The fabricated chipset achieves 2.62-Gb/s PHY data rate, 2.07-Gb/s MAC throughput, and energy consumption of 651 pJ/bit in 3-cm distance.

A new index U* which represents load paths in structures was applied to a truck cab under collision. After obtaining the deformed body by a dynamic crash simulation, U* for the extracted deformed body was statically calculated. The distributions of U* were compared with the values of U** obtained in our previous report. The U* and U** distributions show almost the same pattern. However, the absolute value of U* is larger than U** by about 1.6 times. The difference is inevitable because of the difference in their definitions. The concepts of U*sum and its histogram were used to express the effectiveness of the load transfer. Using these expressions, it was shown that the main member of this cab transfers the loading effectively.

The first 77 GHz frequency modulated continuous wave (FMCW) radar transceiver IC with an accurate FMCW chirp signal generator using a 90 nm CMOS process is presented. To realize accurate FMCW radar system in CMOS, a PLL synthesizer based FMCW generator with chirp smoothing technique that is able to output linear FMCW frequency chirp using a nonlinear reference chirp signal supplied from a low spec/cost digital-oriented frequency reference is applied. The fabricated IC consists of an LNA, a down-conversion mixer with an output buffer, a driver amplifier, a power amplifier with power combiner, an LO distributer and an FMCW synthesizer. The measured FMCW signal from the proposed FMCW generator achieves 93 kHz frequency error (nonlinearity) at the 77 GHz chip signal. Radar performance of the IC has less than 1% ranging error from 1 m to 8 m distance from the measurement in a laboratory. These results show the transceiver achieves a fundamental function for radar applications with 520 mW power consumptions.

A 60-GHz phase-locked loop (PLL) with an inductor-less prescaler is fabricated in a 90-nm CMOS process. The inductor-less prescaler has a smaller chip area than previously reported ones. The PLL operates from 61 to 63GHz and consumes 78mW from a 1.2V supply. The phase noise at 100kHz and 1MHz offset from carrier are -72 and -80dBc/Hz, respectively. The prescaler occupies 80 × 40µm2. The active area of the PLL is 0.31mm2.

A 60-GHz receiver (RX) front-end chip fabricated in 90 nm CMOS process is presented. The RX chip consists of an LNA, a downconversion mixer, and a phase-locked loop synthesizer. The RX chip is capable of generating LO signal from phase-locked synthesizer. The components of the RX chip employ fully differential architecture to avoid influences of parasitic components and operate with low LO signal amplitude. Measured power gain and NF of 22 dB and 8.4 dB were obtained at 61.5 GHz, respectively, and the RX chip receives a radio signal with an on-chip dipole antenna. These results indicate the possibility of realization of a CMOS single-chip 60-GHz transceiver.

The concept of the parameter U* has been introduced by the authors to express load transfer in structures. In this paper, an extended definition of U* is introduced for structures under multiple loadings. The new expression of U* with the matrix formulation of internal stiffness can effectively be applied to an efficient calculation of U* distribution. Examples of U* calculation for an actual truck cab structure under multiple loading are demonstrated. Calculation results of U* for cases under multiple loading condition and single loading condition are compared, and the applicability of St. Venant's principle concerning U* distribution is discussed.

A concept of a parameter U* has been introduced by the authors to express load transfer paths in a structure. In this paper, a new extended expression of U* is introduced, and it is shcown that the new parameter can be applied to structures with complicated multiple support conditions. The present expression that is derived by matrix formulation of internal stiffness and initial deformation includes the definition of U* in the previous report. Examples of U* calculation for structures with multiple support conditions are demonstrated. Calculation results for a simple structure and an actual truck cab body show the effectiveness of the present method of U* calculation.

We propose a novel variable inductor on a Si complementary metal oxide semiconductor (CMOS) chip, whose inductance is of nH-order, for GHz applications. The inductance value can be varied by moving a metal plate above the inductor. The magnetic flux penetrating the spiral inductor continuously varies depending on the position of the metal plate. The metal plate is slid horizontally using a micro electro mechanical system (MEMS) actuator. We present the measured and simulated results. At 2.45 GHz, the inductance is varied from 6.6 nH to 5.7 nH, i.e., the variable range is 13%. These results show that the effect of parasitic capacitance between the spiral inductor and the metal plate can be ignored. The proposed variable inductor can be applied to RF circuits.

The objective of this study is to investigate the load transfer paths in the cabin structures of heavy-duty trucks under static loading, and to apply the results to reduce vibration in cabins. In a preliminary simulation using a simple model, it is shown that the floor panel vibration is closely related to the stiffness of the front cross-member of the floor structure. Load path U* analyses using the finite element method show that the low stiffness of the front cross-member is caused by discontinuities and nonuniformities in the load paths.

We developed a slurry mixing device with microchannels. Each channel has a width of 500@mm and a height of 75@mm with oblique ridges on the wall with the aim of rotating the slurry and enhancing the chaotic mixing efficiency. The effect of the oblique ridges on the slurry mixing efficiency was investigated for various ridge angles (30^o, 45^o, and 60^o). We found that the slurry was successfully mixed by the channels with oblique ridges and that channels with a 45^o ridge angle had the highest mixing efficiency.

A fully-integrated single-chip CMOS transceiver with MAC and PHY for 60GHz proximity wireless communication is presented. A 60GHz wireless communication single-chip transceiver has not yet been reported due to large power consumption issues. However, by limiting the application to high-throughput proximity transmission, thermal issues arising in a single-chip have been overcome. A 2GHz broadband OFDM single-chip transceiver suffers from SNR degradation due to the reference clock (REFCLK) and baseband clock (BBCLK) spurs in RF/analog circuits. Low frequency spurs in the clock generator (CLKPLL) due to the mixing of the ADC/DAC sampling clock (SCLK) and other clocks such as REFCLK and BBCLK have been eliminated by careful frequency planning of those clocks. In addition to that, spur suppression in digital baseband and noise-tolerant RF/analog circuit designs are employed. The spurs have been successfully suppressed to less than -35dBc. The chip achieves a PHY data-rate of 2.35Gb/s and MAC throughput of 2.0Gb/s at a distance of 4cm. Power consumption is scalable to the throughput by the introduction of fast Sleep and Awake modes. The average power consumption at a throughput of 0.2Gb/s is reduced to 36% of that at 2.0Gb/s.

We studied Ar gas cluster ion beam (GCIB) planarization effect on patterned surfaces refilled with Cr, Ta and SiO2. The patterns of 20 nm in depth were fabricated on Si substrate by using electron beam lithography and CHF3 -reactive-ion-etching. The bit pattern pitches and the height of peak-to-valley were 150/200/300/400 nm and 20 nm, respectively. Then, refilling materials were deposited 30 nm in thickness on the patterned substrates. The test samples were irradiated by Ar-GCIB and the resultant surface profiles were measured by atomic force microscopy. Acceleration energy for a cluster was 20 keV. The dose was set from 2 × 1015 to 5 × 1015 ion/cm2. Although there was a difference in the dose, the patterns disappeared clearly by irradiating GCIB. The reduction rate of peak-to valley height decreased with decreases of the pattern pitch. We indicated that GCIB irradiation is effective for the planarization of patterned surface refilled with Cr, Ta, and SiO2.

Structural-acoustic analysis was performed in order to reduce booming noise due to floor panel vibration in heavy duty truck cab. Usually a common cab is used for various truck configurations. Therefore, a robust cab design which allows reduction f booming noise under various cab excitation forces is deemed to be important. As a first step towards this goal, finite element model of a cab floor panel and bounday elment model of a cab cavity were created, and the good correlation of booming noise between the simulation and excitation test was confirmed. In order to propose a rubust cab design, Taguchi Method was applied for a design parameter sstudy of the floor structure. This paper describes the method which can evaluate the effect of design parameters quantitatively with the ratio of main effect variance and interaction variance between main effect and excitation frequency. The parameters for noise reduction over a wide frequency range and paramers for noise reduction at a specified frequency can be discriminated with this method.

High-Q and scalable MOS varactor for mm-wave VCO has been studied. To realize high-Q varactor in mm-wave region, low varactor capacitance and low series resistance of unit cell are essential. Since low varactor capacitance and low series resistance are impossible to realize simultaneously, optimization and scalable model are necessary. This paper presents strategy of high-Q optimization, a novel scalable model for mm-wave varactor, and confirmation results by VCO measurements. The Q of small-geometry varactor improved 30 times at f =30 GHz. The novel scalable varactor model improved its accuracy from 21.9% to 1.7%.

A new parameter U** that represents load paths in structures is applied to a truck cab under collision. Since the main part of a compartment should be maintained in a linear elastic condition, a linear U** analysis can be applied. U** for the deformed body is statically calculated from the extracted deformation results of a crash simulation. A substitution-modulus method is applied to reproduce the material and geometrical nonlinearities. An index "m2-4msU**" is proposed as a standard condition for the truck cab. The predominant load paths along the floor member and the shear effect of the floor panel are demonstrated.

A novel Marchand balun-based parallel power combiner suitable for a 60-GHz CMOS power amplifier is proposed. It improves the power efficiency by solving the issues of the phase difference of the signals to be combined and the low coupling factor of the on-chip balun in scaled CMOS technologies. The power amplifier using the proposed power combiner is fabricated in a 90 nm CMOS process with 1.2 V supply. Measured power gain, output referred 1-dB compression point, and saturated output power are 11.2 dB, +8.3 dBm, and +11.2 dBm, respectively, at 60-GHz.

A 60-GHz phase-locked loop (PLL) with inductor-less prescaler is fabricated in a 90-nm CMOS process. The inductor-less prescaler has a smaller chip area than previously reported ones. The PLL operates from 61 to 63 GHz and consumes 78 mW from a 1.2 V supply. The phase noise at 100 kHz and 1 MHz offset from carrier are -72 and -80 dBc/Hz, respectively. The prescaler occupies 80 x 40 mum2. The active area of the PLL is 0.6 x 0.6 mm2.

A 60-GHz receiver (RX) chip fabricated in 90 nm CMOS process is reported. The RX chip consists of an LNA, a downconversion mixer and a phase-locked loop synthesizer. The RX chip is capable of generating LO signal from phase-locked synthesizer. Measured power gain and NF of 22 dB and 8.4 dB were obtained at 61.5 GHz. These results indicate the possibility of realization of CMOS single-chip 60-GHz transceiver.

A 5 GHz MIMO direct-conversion transceiver composed of 2 transmitters (TXs) and 3 receivers (RXs) is fabricated with 0.13 mum CMOS technology. Die size is 4.56 mm times 7.7 mm. For driving 10 GHz LO signal lines of 5 mm length for both TXs and RXs, inductor-less low-power LO repeaters are equipped in individual LO paths. A linearized RF variable gain amplifier is proposed for low power operation. Isolation of over 40 dB is obtained by equipping separate GNDs on both the MIMO IC and the circuit board. This results in negligible degradation of EVM. TX EVM of over -31 dB is obtained at -8.6 dBm for 2 TX mode when external LO of 10 GHz is applied. The 3 RXs and 2 TXs with LO paths dissipate 703 mW and 412 mW from 1.5 V, respectively.

This paper describes the structural optimization technique with FEM optimization technology. The design shape of engine components have been optimized with consideration of dynamic effects. In the conventional approach of structural optimization in a Multibody Dynamics (MBD) system, the loads on FEM models of components as boundary conditions for subsequent shape optimization were used to be an output from MBD analysis. When an MBD system was optimized in MBD analysis, the body properties were used to be optimized instead of component shape. In this study a special modeling approach is followed to capture the loads easily and accurately with respect to contact behavior of metal bearings existing in engine components in order to improve the conventional approach with rigid elements. This approach is applied to the piston-crankshaft system of a one-cylinder engine. Topology optimization is performed to detect the effective design parameters of connecting rod (con-rod) shape to reduce weight prior to the shape optimization. Shape optimization of the con-rod results in a 6% weight reduction under the condition of critical compression loading just after the TCD (top dead center) of the combustion process. Furthermore, the structure modification for a piston based on an FE model also inside MBD analysis is performed. The base vectors of FEM morphing technology are used as design variables instead of body properties. These techniques are advanced approaches of structure modification based on FE model for MBD system.Copyright © 2007 by ASME

The authors made an error in Fig. 19 in the above-named article [ibid., vol. 47, no. 12, pp. 3160–3171, Dec. 2012]. The figure is the same as Fig. 13 by mistake. The correct figure "Data rate/throughput measurement setup" is shown here. The authors apologize for any confusion.