JxB Arc Jet Fullerene Producer with a Revolver Type Automatic Material Injector

In order to produce various kinds of fullerenes efficiently, a J×B arc jet fullerene reactor with a revolver type automatic and continuous material injector has been developed. The J×B force reduces deposition of carbon vapor on a cathode and increases production rate of fullerenes. Effective production of LaC₆₀ and LaC₇₀ is also obtained by this reactor.     

Effect of defects and moisture on insulation characteristics of XLPE insulated cable

Sample cables having a few types of defects (such as voids, contaminants, and protrusions) with more volume than usual, were prepared intentionally to clarify how these defects affect separately insulation characteristics under the presence/nonpresence of moisture. In the case of void inclusion, insulation characteristics are even more susceptible to ac voltage than impulse voltage, and the distribution of lifetimes is classified into a wornout failure type due to discharge deterioration. While protrusions and some other contaminants can greatly deteriorate original dielectric strength, these defects have a relatively slight effect on long-term endurance in the atmosphere. Therefore, the distribution of lifetimes is classified into an early-failure type. With reference to the influence of moisture, in a strong electric field (exceeding 15 kV/mm) and in a short-term region, there is an increase in harmfulness around defects with water absorbed, thereby inducing electrical trees and resulting in a breakdown. In the light electric field (no more than 15 kV/mm) and in a long-term region, harmfulness of defects will not deepen to a considerable extent, and the growth of water trees very possibly is influential.     

Efficient production of the C-terminal domain of secretory leukoprotease inhibitor as a thrombin-cleavable fusion protein in Escherichia coli

We have developed a high-level production system for the C-terminaldomain of secretory leukoprotease inhibitor (SLPI) to investigateits pharmacological activities. A gene for the C-terminal domainof SLPI, (Asn55-AlalO7)SLPI, was constructed from chemicallysynthesized deoxyoligonucleotides. It was fused to a gene forthe N-terminal portion of human growth hormone via a DNA sequenceencoding Leu-Val-Pro-Arg, which can he cleaved by thrombin.The fused gene was expressed in Escherichia coli under the controlof a trp promoter, and the fusion protein was obtained as aninclusion body. After sulfonation of the cysteine residues,the sulfonated fusion protein was cleaved at the desired siteby thrombin. Sulfonated (Asn55-Ala107)SLPI was refolded in Trisbuffer containing reduced and oxidized glutathione. The resulting(Asn55-Ala107) SLPI was purified by cation-exchange chromatographyand reverse-phase high performance liquid chromatography. Thefinal yield was 50 mg/l culture. (Asn55-Ala107)SLPI was as activeagainst elastase as, but had less trypsin inhibitory activitythan, native SLPI. This system is suitable for the large-scaleproduction of the C-terminal domain of SLPI, which is an elastase-specificinhibitor.     

Flow characteristics on a heated rotating disc under natural convection dominant conditions

Characteristics of circumferential vortices, which emerge on a heated rotating disc under natural convection dominant conditions, have been studied experimentally. The techniques of laser induced fluorescence (LIF) and particle image velocimetry (PIV) have been utilized as a non-invasive method to obtain two-dimensional temperature and velocity distributions, respectively. The results show that the frequency of appearance of the vortex increases with increasing buoyancy effect. The ensemble averages of the temperature and vertical velocity as well as those of RMS values of temperature and vertical velocity fluctuations are large in the vortex. Most of heat is transferred vertically by fluctuations in the vortex.     

Crack propagation of steels during low cycle thermal-mechanical and isothermal fatigue at elevated temperatures

The surface and through crack propagation of three high temperature steels in low cycle thermal-mechanical and isothermal fatigue at elevated temperatures was investigated. The rate of crack propagation obtained was correlated with the range of cyclicJ-integral, ΔJf. It was found that there is a linear relationship on alog-log plot regardless of materials, test conditions, and crack configurations. Furthermore, fatigue life predicted by integrating the equation of crack propagation was compared with experimental results.     

Motion Coherent Tracking Using Multi-label MRF Optimization

We present a novel off-line algorithm for target segmentation and tracking in video. In our approach, video data is represented by a multi-label Markov Random Field model, and segmentation is accomplished by finding the minimum energy label assignment. We propose a novel energy formulation which incorporates both segmentation and motion estimation in a single framework. Our energy functions enforce motion coherence both within and across frames. We utilize state-of-the-art methods to efficiently optimize over a large number of discrete labels. In addition, we introduce a new ground-truth dataset, called Georgia Tech Segmentation and Tracking Dataset (GT-SegTrack), for the evaluation of segmentation accuracy in video tracking. We compare our method with several recent on-line tracking algorithms and provide quantitative and qualitative performance comparisons.     

Inclination of mold pattern’s sidewalls by combined technique with photolithography at defocus-positions and electroforming

We succeeded in achieving inclined sidewalls in a positive-tone photoresist structure by adjusting the focus offsets in a projection ultraviolet (UV) lithography system. In our experiments, highly precise patterns on Ni-electroformed mold were replicated from a photoresist master. The practicality of the mold was then evaluated by thermal nanoimprint experiments on polycarbonate (PC). When the focus offsets became small by moving the UV image plane (defined by wafer surface) closer to the lens the inclined angles of the photoresist walls increased. In this work, the release force was measured using a desktop nanoimprint system equipped with a load cell that measured not only the compression power but also the tensile force in the de-molding process. Starting from the glass transition temperature T _g (144°C) of PC, the heating temperature in the molding process was changed by increments of 10°C resulting in T _g + 10, T _g + 20, and T _g + 30°C. The result showed that the release force decreased with increasing incline angles. It was observed that the more inclined the sidewalls of the mold pattern were, further small the release forces became, and the mold pattern became to be defended from deformation.     

Coalition structure generation in cooperative games with compact representations

This paper presents a new way of formalizing the coalition structure generation problem (CSG) so that we can apply constraint optimization techniques to it. Forming effective coalitions is a major research challenge in AI and multi-agent systems. CSG involves partitioning a set of agents into coalitions to maximize social surplus. Traditionally, the input of the CSG problem is a black-box function called a characteristic function, which takes a coalition as input and returns the value of the coalition. As a result, applying constraint optimization techniques to this problem has been infeasible. However, characteristic functions that appear in practice often can be represented concisely by a set of rules, rather than treating the function as a black box. Then we can solve the CSG problem more efficiently by directly applying constraint optimization techniques to this compact representation. We present new formalizations of the CSG problem by utilizing recently developed compact representation schemes for characteristic functions. We first characterize the complexity of CSG under these representation schemes. In this context, the complexity is driven more by the number of rules than by the number of agents. As an initial step toward developing efficient constraint optimization algorithms for solving the CSG problem, we also develop mixed integer programming formulations and show that an off-the-shelf optimization package can perform reasonably well.     

Compensation for dead band of force measurement based on the coefficient of restitution in a hybrid simulator

In order to develop space robotic technologies, the feasibility and reliability of the systems have to be verified by repetitive operation tests. A hybrid simulator (also referred to as a Hardware-in-the-loop simulator) is one of the effective ways to examine orbital operations on the ground. The simulator embeds a hardware experiment in a numerical simulation loop. However, it is known that the hybrid simulator has a serious problem that energy increase arises in contact with a hardware experiment in the loop. In general, the energy increase in the hybrid simulator occurs due to the dead time in the system. However, this paper presents that dead band in force/torque measuring also causes the energy increase. The dead band in the force/torque measuring is necessary to avoid unexpected motion of the hybrid simulator due to the noise data in the force/torque sensor. This paper proposes two compensation methods for the energy increase problem due to the dead band. The first method is to insert a virtual damper to absorb the increased energy during the contact. The second method is to extrapolate force/torque data that is lost through the dead band processing right after the contact. The experimental verification with uniaxial contact in hybrid simulator is carried out to validate the proposed compensation methods.