Fabrication of high current and low profile micromachined inductorwith laminated Ni/Fe core

A new process for the fabrication of high current and very low profile micromachined inductors has been developed. This process involves the combination of mechanical lamination and electrodeposition of copper windings by means of LIGA-like lithography through thick epoxy photoresists. The dimension of the fabricated inductor is 16 mm×19 mm×1 mm. The fabricated inductor has an inductance value of 1.2 μH with DC saturation current of 3 A and an electrical resistance of less than 30 mΩ at 10 kHz     

Theory and implementation of path planning by negotiation for decentralized agents

This paper presents a cooperative decentralized path-planning algorithm for a group of autonomous agents that provides guaranteed collision-free trajectories in real-time. The algorithm is robust with respect to arbitrary delays in the wireless traffic, possible sources being transmission time and error correction. Agents move on reserved areas which are guaranteed not to intersect, therefore ensuring safety. A handshaking procedure guarantees recent information states for the agents. Conflicts between agents are resolved by a cost-based negotiation process. The basic algorithm is augmented by the introduction of waypoints, which increase performance at the cost of additional wireless traffic. An implementation of the algorithm is tested in simulation and successfully applied to a real system of autonomous robots. The results are presented and discussed.     

Optimization of salts in medium for production of carboxymethylcellulase by a psychrophilic marine bacterium, <Emphasis Type="Italic">Psychrobacter aquimaris</Emphasis> LBH-10 using two statistical methods

The concentration of four mineral salts in the medium for the production of carboxymethylcellulase (CMCase) by Psychrobacter aquimaris LBH-10 were optimized using orthogonal array method (OAM) and response surface method (RSM) and their results from two statistical methods were compared. The analysis of variance (ANOVA) of data from central composite design (CCD) based on OAM indicated that potassium phosphate gave the highest percentage participation for cell growth as well as production of CMCase. However, their relative participations of four salts for cell growth were different from those for production of CMCase. The ANOVA of results from RSM indicated that highly significant factors (“probe>F” less than 0.0001) for cell growth were K₂HPO₄ and (NH₄)₂SO₄, whereas those for production of CMCase were K₂HPO₄, NaCl, and MgSO₄·7H₂O. The optimal concentration of K₂HPO₄, NaCl, MgSO₄·7H₂O, and (NH₄)₂SO₄ for cell growth extracted by Design Expert Software based on RSM were 7.10, 0.84, 0.24, and 0.33 g/L, respectively, whereas those for production of CMCase were 3.00, 0.52, 0.34, and 0.45 g/L. The optimal concentrations of salts for cell growth and production of CMCase using RSM basically coincided with those using OAM as well as those from ‘one-factor-at-a-time’ method. The production of CMCase by P. aquimaris LBH-10 with optimized concentrations of salts was 273.0 U/mL, which was enhanced by 1.27 times higher than the previous report.     

ROS-Mediated Anti-Tumor Effect of Coptidis Rhizoma against Human Hepatocellular Carcinoma Hep3B Cells and Xenografts

Coptidis Rhizoma is the dried rhizome from the Coptis chinensis Franch. that has been shown to have a number of beneficial pharmacological properties including antioxidant, anti-inflammatory, and anti-cancer effects. However, the anti-cancer effects of Coptidis Rhizoma on hepatocellular carcinoma (HCC) remain unclear. In this study, we investigated the anti-cancer properties of Coptidis Rhizoma ethanol extract (CR) in HCC Hep3B cells and in a xenograft mouse model. Our results showed that the CR significantly inhibited cell growth and induced apoptosis in Hep3B cells through increased expression of Bcl-2 associated x-protein (Bax) and cleavage of poly-ADP ribose polymerase (PARP), reduced expression of Bcl-2, and activated caspases. CR also increased the generation of intracellular reactive oxygen species (ROS), which caused a loss of mitochondrial membrane potential (MMP, ΔΨm) and activation of the mitochondria-mediated intrinsic apoptosis pathway. Moreover, N-acetylcysteine (NAC), a ROS inhibitor, markedly blocked the effects of CR on apoptotic pathways. CR also induced the expression of light chain 3 (LC3)-I/II, a key autophagy regulator, whereas CR-mediated autophagy was significantly suppressed by NAC. In addition, pre-treatment with NAC perfectly attenuated the inhibition of cell invasion and migration of CR-stimulated Hep3B cells. Furthermore, oral administration of CR suppressed Hep3B tumor growth in xenograft mice without toxicity, alterations to body weight, or changes in hematological and biochemical profiles. Taken together, our findings suggest that CR has anti-tumor effects that result from ROS generation, and may be a potential pharmacological intervention for HCC.     

Multi-View Multi-Modal Head-Gaze Estimation for Advanced Indoor User Interaction

Gaze estimation is one of the most promising technologies for supporting indoor monitoring and interaction systems. However, previous gaze estimation techniques generally work only in a controlled laboratory environment because they require a number of high-resolution eye images. This makes them unsuitable for welfare and healthcare facilities with the following challenging characteristics: 1) users’ continuous movements, 2) various lighting conditions, and 3) a limited amount of available data. To address these issues, we introduce a multi-view multi-modal head-gaze estimation system that translates the user’s head orientation into the gaze direction. The proposed system captures the user using multiple cameras with depth and infrared modalities to train more robust gaze estimators under the aforementioned conditions. To this end, we implemented a deep learning pipeline that can handle different types and combinations of data. The proposed system was evaluated using the data collected from 10 volunteer participants to analyze how the use of single/multiple cameras and modalities affect the performance of head-gaze estimators. Through various experiments, we found that 1) an infrared-modality provides more useful features than a depth-modality, 2) multi-view multi-modal approaches provide better accuracy than single-view single-modal approaches, and 3) the proposed estimators achieve a high inference efficiency that can be used in real-time applications.     

Application of statistical experimental design for optimization of physiological factors and their influences on production of pullulan by <Emphasis Type="Italic">Aureobasidium pullulans</Emphasis> HP-2001 using an orthogonal array method

Physiological factors for the production of pullulan by A. pullulans HP-2001 were optimized using orthogonal array method and their influences were compared using Qualitek-4 software. The analysis of variance (ANOVA) indicated that the most important factor for cell growth was yeast extract, whereas that for production of pullulan was glucose. The optimal conditions for cell growth were found to be 100.0 g/L glucose, 10.0 g/L yeast extract, and initial pH of 6.0, whereas those for the production of pullulan were 100.0 g/L glucose, 2.5 g/L yeast extract, and initial pH of 5.5. Among four mineral salts in the medium, potassium phosphate (K₂HPO₄) was found to be the most important factor for cell growth as well as production of pullulan. Next important salt for cell growth was (NH₄)₂SO₄, whereas that for production of pullulan was NaCl. The optimal concentrations of K₂HPO₄, NaCl, MgSO₄·7H₂O, and (NH₄)₂SO₄ for cell growth were 7.5, 1.00, 0.1, and 1.20 g/L, respectively, whereas those for production of pullulan were 2.5, 0.25, 0.8, and 0.30 g/L. The expected cell growth and the production of pullulan by A. pullulans HP-2001 under these optimized conditions were 12.61 and 11.49 g/L, respectively.     

Application of statistical experimental design for optimization of downstream process for recovery of pullulan produced by <Emphasis Type="Italic">Aureobasidium pullulans</Emphasis> HP-2001

The optimal conditions of the downstream process for recovery of pullulan produced by Aureobasidium pullulans HP-2001 were examined using response surface method (RSM). The optimal amount of diatomite in filter press and the optimal flow rate in a continuous flow centrifuge for removal of cells from the culture broth of A. pullulans HP-2001 were found to be 5.0% (v/v) and 2.0 L/min. Based on central composite design (CCD) experiments and analysis of variance (ANOVA) indicated that the optimal conditions for recovery of pullulan from the supernatant by precipitation were the volume ratio of ethanol (or isopropanol) to supernatant of 3.0: 1.0, the reaction time of 29.5 h, and the reaction temperature of 20.2 °C. The expected maximal recovery yields of pullulan using ethanol and isopropanol under optimized conditions were 79.2 and 85.5%, respectively.     

Creep and tensile properties of press molding joined GMT-sheets

GMT-sheet is used in automobile bumper with high rigidity and strength, and its joining strength is influenced by lap length, one of the joined molding conditions. Fracture strength was calculated by dividing fracture load with cross-sectional area. Total five repeated measurements were made to obtain the average value. Tensile test was conducted at room temperature for 10 specimens. In addition, the effect of compression ratio on creep and tensile performance during lap joined molding was discussed. With increasing lap length, the lap joining efficiency of GMT-sheet was increased. However, higher compression ratio reduced the joining efficiency. Creep test on GMT-sheet showed abrupt fracture without tertiary creep. This can be explained by the weak thermal resistance of the resin. If GMT-sheet was exposed to high temperature for a long time, it was easily failed by external force.     

Polymer-core conductor approaches for RF MEMS

In many radio frequency (RF) microelectromechanical systems (MEMS) applications, currents are confined to the outermost portions of conductors due to the skin effect. Conductors consisting of polymer cores coated with metal, the so-called polymer-core conductor, are appropriate to consider for these applications, and in many instances are easier to fabricate than their solid-metal-core counterparts. Implementation of polymer-core conductors using an SU-8 epoxy-core patterning and subsequent metal electrodeposition is reported. The SU-8 core approach allows for relatively simple formation of extremely high-aspect-ratio columns for inductor sidewalls. In addition, an SU-8 bridge fabrication technique has been realized using a double exposure and single develop scheme. The bridge thickness has been characterized as a function of the optical dose and the post bake time in an oven. Three-dimensional, high-aspect-ratio, high Q-factor, solenoid-type RF inductors are fabricated and tested to demonstrate the feasibility of the polymer-core conductor approach for RF applications. A single, vialess metallization over SU-8 back-bone structure provides the complete conducting paths of the inductor. A single turn inductor that is 900 /spl mu/m in height and 600 /spl mu/m in lateral extension shows a maximum Q-factor of 84 and an inductance of 1.17 nH at 2.6 GHz.     

Effects of Alkaline-Earth-Metal Addition on the Sinterability and Microwave Characteristics of (Zr,Sn)TiO4 Dielectrics

The sinterability and microwave dielectric properties of (Zr_0.8Sn_0.2)TiO₄ with additions of 1 mol% of magnesium, calcium, strontium, or barium were examined. All the alkaline-earth metals were effective for densification, and the order of effectiveness was as follows: Mg < Ca < Sr < Ba. The dielectric constant and the temperature coefficient of the resonant frequency were not influenced very much by the additives; however, a strong deterioration of the quality factor ( Q ) did occur when magnesium was added. The presence of grain-boundary phases was confirmed via microstructural observation, using transmission electron microscopy. In addition, energy-dispersive X-ray analysis was performed to investigate the cause of the deterioration in the Q value.