The evolution of the integrated circuit technology during the last 3 decades has been based on an increasing accuracy of the manufacturing process. With this principle and by using a quality control at the end of the production line (Test Technology) the semiconductor industry has reached very high productivity levels. However, with technology reaching critical sizes (<65nm) the manufacturing control is starting to fail and new design principles have to be introduced to be able to produce functional chips from low quality components. In this article two scenarios partially addressing the problem with gradual introduction of redundancy are considered: the scenario of the era at the end of the CMOS Moore's Law and the expected next scenario of nanoelectronic technology using new emergent devices. In the paper techniques for the design of robust electronic systems in spite of the low quality of components are presented for the two scenarios.

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The goal of replacing ‘conventional’ Al alloys with Al-Li alloys to reduce weight of aerospace structures has had only limited success to date, despite one of the largest alloy-development programs ever undertaken. One of the reasons being, for some product forms and crack-plane orientations, fracture toughness is lower compared with conventional Al alloys due to a greater propensity for low-energy intergranular fracture. Proposed explanations for brittle intergranular fracture include: (i) planar slip resulting in high stresses where slip bands impinge on grain-boundaries, (ii) embrittlement due to alkali-metal-impurity phases, and (iii) grain-boundary structural changes associated with segregation of lithium. The present paper reviews evidence for and against these proposed mechanisms based on (i) studies of 8090 and 2090 alloys, and the more recently developed 2297 alloy, and (ii) comparisons of fracture of these alloys with other materials that exhibit grain-boundary weakness. It appears that lithium segregation to grain boundaries is the prime cause of low-energy intergranular fracture in Al-Li alloys. Embrittlement by alkali-metal impurities is not important providing that impurity levels are less than about 5 ppm (as is the case for most commercially produced alloys). Planar slip and other factors probably play only a minor role.

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Nano-interfacial dielectric polarization phenomena were discussed from the viewpoint of electronics, paying attention to the alignment of dipoles and dipolar energy. Firstly, we summarized dielectric polarization phenomena of monolayer comprised of polar molecules, and showed that monolayer is quite different from bulk materials, and the unique dielectric properties of monolayers can be discussed in terms of orientational order parameters. Maxwell-displacement-current (MDC) measurement coupled with optical second harmonic generation (SHG) measurement is shown as an effective way for detecting unique dielectric polarization phenomena of surface monolayers. Then, the importance of dielectric energy is discussed from the viewpoint of monolayer pattern formation and pointed out that the control of dipolar energy can be new pattern formation technology.

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Sphingolipids such as ceramide and glycosylceramide have recently attracted intense research interests because of their roles as signalling molecules in many important physiological processes, such as apoptosis, inflammation and immune responses. Their well-defined modular structures are ideally amenable to library formation for medicinal chemistry investigations. We have developed practical, divergent synthetic routes to sphingosine and phytosphingosine isomers as well as to carba-sugar analogues of all D-aldohexopyranose isomers toward these goals. And then we have proceeded to prepare ceramide libraries, composed of more than 500 compounds each, based on these sphingosine and phytosphingosine isomers, and demonstrated their utility in cell-based bioassays involving activation of NF- KB and induction of apoptosis. We are also in the process of forming libraries of mono-glycosylceramide and mono-carba-glycosylceramide.

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The 3-dimensional atom probe is based on field ion microscopy where the screen is replaced by a 2-dimensional, position sensitive detector. Atoms were removed from a conducting sample by a high voltage pulse. The time of flight reveals their chemical nature, and continuous stripping allows lateral and in-depth analysis. The spatial resolution permits a chemical analysis on the sub-nanometer scale. Results of this new technique are presented for (i) the initial stages of interdiffusion at the boundary between two metals, (ii) P-segregation at grain boundaries in nanocrystalline Ni-P alloys, (iii) initial stages of nucleation and growth in various alloys, (iv) composition of thin oxide films in TMR-structures, and (v) distribution of hydrogen in metallic multilayers. It will be also shown that the new technique not only allowed a characterization on the atomic scale but verified and/or falsified existing models for the examples given before.

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Biosynthetic genes of kasugamycin (KSM), an aminoglycoside antibiotic produced by Streptomyces kasugaensis, forms a cluster within the chromosome. A cloned 22.4-kb cluster region contains almost all the enzyme-coding genes required for KSM biosynthesis together with kac³³⁸, a gene for KSM acetyltransferase, and kasKLM, a set of genes encoding an ABC transporter, both of which participate in KSM self-resistance as well as kasT encoding a KSM-synthesis-specific transcriptional activator of the biosynthetic genes. Furthermore, rpoZ, encoding a 90-amino acid omega (ω) subunit of RNA polymerase (RNAP), is required for the simultaneous production of KSM and aerial mycelium, and rpoZ-disrupted wild-type S. kasugaensis produces neither KSM nor aerial mycelia. Transcriptional analysis of the biosynthetic genes and forcible expression of kasT in the mutant revealed that the presence of rpoZ, which results in formation of RNAP carrying the ω subunit, facilitates initiation of kasT transcription and is thus crucial for KSM production.

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Hot deformation behaviors of a ZK60 magnesium alloy were investigated by hot compressive tests on a Gleeble-1500 thermal simulation test machine at temperatures ranging from 473 K to 723K and strain rates of 0.01-1s^-1. Microstructures evolution of the alloy as well as dynamic recrystallization mechanisms at different strains with the strain rate 0.1s_-1 at 623K were examined under optical microscope (OM) and transmission electron microscope (TEM). The relationships between flow stress, strain rate and deformation temperature were analyzed, and the deformation activation energy at elevated temperatures (573-723K) were calculated. The results indicated that under the present deformation conditions, dynamic recrystallization happened in the alloy and fine recrystallized grains tended to form ductile shear zones under the large strain condition; and there were different dynamic recrystallization mechanisms at different strains; within the temperature range from 573K to 723K, deformation activation energy changed with the deformation temperature and strain rate.

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In this study, the role of fly ash as a grinding aid to facilitate fine grinding of limestone for improved flowability was examined by carrying out batch grinding test for varying feed amount and grinding time, while maintaining the limestone to fly ash ratio at 5: 1. As a result, it was found that fly ash was an effective grinding aid for the fine grinding of limestone, and the optimum feed amount of limestone and fly ash to the grinding mill increased with increase of grinding time.

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The synthesis of 9, 10-bis (3, 5-dihydroxy-1-phenyl) anthracene-tetrakis β-cyclodextrin was synthesizedfrom DCC coupling between anthacene-tetracarboxylic acid and amino β-cyclodextrin in a high yield. 1HNMR, IR and TOF-mass spectroscopy carried out the identification of the titled compound. TOF-mass spectroscopyshows a molecular weight peak at 4970.40, which means (M+Na)⁺ peak. In this study, weinvestigated to form supramolecular assembly mediated by guest molecule.

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In the present work, the energy recovery and the mechanical recycling, i.e. two treatment options forplastic wastes from the discarded TV sets have been assessed and compared in the context of the life cycleassessment methodology (LCA). The environmental impact of each option was assessed by calculatingthe following impact indicators: energy depletion (ED), depletion of abiotic resources (ADP), and global warming potential (GWP). Then, the indicators were compared and the option with the smallerenvironmental impact was selected. The main finding of this study was that mechanical recycling ofplastics is more attractive treatment option in environmental terms than incineration for energy recovery.

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The biggest illegal dumping site in Japan was found on the border between Iwate and Aomori Prefecturesabout 50 km away from Hachinohe city. It caused major social problems such as environmentalcontamination and must be reverted to its natural state. To monitor and analyze the environmental changes, a remote sensing system was established using artificial satellites and on-site sensors. From February, 2004, a large amount of data including satellite images, water quality data and weather data has been collectedusing this system. In this paper, these data was analyzed to explain the state of contamination and the stateof recovery. Satellite images from several different satellite sensors were combined for vegetation analysisand topographic analysis. The result manifested topographic characteristics of the site and the changes ofgreen vegetation. And the relationship between the changes of water quality and the existence or the removalof industrial wastes was explained. These will be powerful tools for dealing with industrial waste.

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Recently, the analysis of geographical features by digital elevation models (DEM) which are made fromsatellite images, has become a widely researched topic. However, espacially in the case of old satelliteimage, DEM or the stereo pair to make it might be hard-to-find. Then we developed the estimation methodfor three-dimensional detailed geographical features shape using shadow of satellite images. In this study, weinvestigated the influence on the result of estimation by choosing the boundary of a shadow. Also, weexamined the threshold of the brightness to discern the shadows of geographical features from old satelliteimages.

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Optical films are currently used for a range of optical components. The aim of this research was toprepare wavelength selective transmission thin films which can improve the performance of solar cells.Radio frequency (RF) sputtering equipment was used for depositing the wavelength selective transmissionthin film. The deposition of layers of various materials and of different thicknesses was carried out aftersoftware simulation of the wavelength selective transmission thin film. The experimental wavelengthselective transmission thin film was deposited on quartz glass, and the optical characteristics of the thinfilm were measured with a spectrophotometer. The transmission results showed that the designed wavelengthselective transmission thin film could be fabricated. The transmission range can be controlled by depositinglayers of different materials and thicknesses.

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Mesostructured composites of layered perovskites and cationic surfactants were synthesized. Layeredperovskite HC_a2Nb₃O₁₀ and alkyltrimethylammonium (C_nTMA) or alkylpridinium (C_nPy) surfactantsformed lamellar-type composites. The interlayer spacings of the composites increased with increasing carbonnumber of alkyl group in the surfactants. The spacings were also affected by the Nb: surfactant ratio in thereacting solutions. From comparison between size of molecule and interlayer spacing, it is suggested thattwo types of composites formed, which contain C₁₆Py⁺ ions with mono-or bilayer arrangements.

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Friction stir welding (FSW) experiments were conducted using three different aluminium alloys (a workhardened alloy, an age hardened alloy and a cast alloy) followed by metallographic examination focusingon the upper weld zone and the surface layer. The examination has revealed the features of the majorforward flow resulting from the forward motion of the tool shoulder. A thin shear layer due to tool rotationwas identified between the tool shoulder and the workpiece with a distinctive shear flow direction. Thethickness of the shear layer was alloy dependent. An embedded layer in the upper weld zone has also beenidentified. The flow phenomena leading to this will be discussed. A velocity profile in the shear layer, basedon the apparent alignment of Si particles in the cast alloy after welding, has suggested a dominant slidingcontact condition.

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