Strict Alignment Research Articles

Proposal of Two-Dimensional Self-Matching Receiver Using Chaotic Spatial Synchronization for Free Space Optics Communication System and Its Application to Image Transmission and Code Division Multiplexing

This paper proposes a two-dimensional self-matching receiver for Free Space Optics (FSO) communication system using chaotic spatial synchronization. This system is able to obtain the information of two-dimensional code from received pattern. This paper considers that proposed system is applied to two applications. The first application is image transmission. This paper shows that applying proposed system to image transmission enables to restore the desired image, which doesn't require strict alignment of receiver, and evaluates transmission optical power. The second application is Code Division Multiplexing (CDM). This paper shows that applying proposed system to CDM system enables to demodulate desired digital signals regardless of the uncertainty of received position. Moreover, the required transmission optical power and bit error rate performance are obtained by computer simulation.

Self-Written Waveguide Optical Pin Fabricated Using Photomask Transfer Method

This letter reports on a new self-written waveguide (SWW) optical interconnection pin. The SWW-pin is formed directly on an optical device using a photomask transfer method and has a 45deg mirror on the end-face. The processed end-face provides 90deg optical path redirection and enables strict handling and alignment in optical interconnections on an optoelectronic printed-wiring board. We present 90deg path redirection characteristics of an SWW-pin having a coupling loss of 1.1 dB

Multiple Faces of Codification: Organizational Redesign in an IT Organization

This paper details a longitudinal interpretative field study of an information technology (IT) organization in which a new chief information officer (CIO) implemented a major organizational redesign. The redesign increased the degree of codification in activities of the IT organization so as to control, coordinate, and deliver services more cost effectively to its business clients. We examine different stakeholders’ views of the change, the implementation processes, and the consequences of the redesign. The case analysis emphasizes specific challenges that designers of support organizations face when increasing the degree of codification. Key implications include the need for these designers to (1) pay as much, if not more, attention to the local organizational context as they do to the external environmental conditions; (2) communicate and negotiate constantly with various stakeholders concerning the appropriate degree of codification and control; (3) be wary of how a strict alignment of all design elements can blind the designer to important, unrecognized issues; and (4) consider that increased codification may help support organizations compete more efficiently with external vendors, but may also ease the process of outsourcing.

Preparation of a Mesoporous Silica Film with a Strictly Aligned Porous Structure through a Sol−Gel Process

A novel strategy for the preparation of a mesoporous silica film, in which the in-plane alignment of the honeycomb packed mesochannels is strictly controlled, is developed. The highly aligned porous structure is achieved by using a substrate with a rubbing-treated polyimide coating in the evaporation induced self-assembly process. It is shown that the controlled porous structure is formed over the entire thickness of the film and that the alignment distribution is much narrower than that in the films prepared by the conventional process based on a heterogeneous nucleation and growth mechanism. In the present process, the aligned porous structure would be formed through a directional lamellar-to-hexagonal phase transition from the substrate surface toward the air/film interface. The new formation mechanism as well as the lower process temperature enables the observed strict alignment control of the mesochannels.

A normalization strategy applied to HiCEP (an AFLP-based expression profiling) analysis: Toward the strict alignment of valid fragments across electrophoretic patterns

BackgroundGene expression analysis based on comparison of electrophoretic patterns is strongly dependent on the accuracy of DNA fragment sizing. The current normalization strategy based on molecular weight markers has limited accuracy because marker peaks are often masked by intense peaks nearby. Cumulative errors in fragment lengths cause problems in the alignment of same-length fragments across different electropherograms, especially for small fragments (< 100 bp). For accurate comparison of electrophoretic patterns, further inspection and normalization of electrophoretic data after fragment sizing by conventional strategies is needed.ResultsHere we describe a method for the normalization of a set of time-course electrophoretic data to be compared. The method uses Gaussian curves fitted to the complex peak mixtures in each electropherogram. It searches for target ranges for which patterns are dissimilar to the other patterns (called "dissimilar ranges") and for references (a kind of mean or typical pattern) in the set of resultant approximate patterns. It then constructs the optimal normalized pattern whose correlation coefficient against the reference in the range achieves the highest value among various combinations of candidates. We applied the procedure to time-course electrophoretic data produced by HiCEP, an AFLP-based expression profiling method which can detect a slight expression change in DNA fragments. We obtained dissimilar ranges whose electrophoretic patterns were obviously different from the reference and as expected, most of the fragments in the detected ranges were short (< 100 bp). The normalized electrophoretic patterns also agreed well with reference patterns.ConclusionThe normalization strategy presented here demonstrates the importance of pre-processing before electrophoretic signal comparison, and we anticipate its usefulness especially for temporal expression analysis by the electrophoretic method.

Actively Seeking Activating Sequences

I thank R. Brent, I. Cartwright, L. Keegan, Z. Liu, M. Ptashne, and M. Xu for comments. I apologize that the page limit did not permit citation of all relevant work. This work was supported in part by the AHA and the NSF.

Optical wireless communication through fog in the presence of pointing errors.

Terrestrial optical wireless communication (OWC) is emerging as a promising technology, which makes connectivity possible between high-rise buildings and metropolitan and intercity communication infrastructures. A light beam carries the information, which facilitates extremely high data rates. However, strict alignment between the transmitter and the receiver must be maintained at all times, and a pointing error can result in a total severance of the communication link. In addition, the presence of fog and haze in the propagation channel hampers OWC as the small water droplets scatter the propagating light. This causes attenuation due to the resultant spatial, angular, and temporal spread of the light signal. Furthermore, the ensuing low visibility may impede the operation of the tracking and pointing system so that pointing errors occur. We develop a model of light transmission through fogs of different optical densities and types using Monte Carlo simulations. Based on this model, the performance of OWC in fogs is evaluated at different wavelengths. The handicap of a transceiver pointing error is added to the model, and the paradoxically advantageous aspects of the transmission medium are exposed. The concept of a variable field of view receiver for narrow-beam OWC is studied, and the possibility of thus enhancing communication system performance through fog in an inexpensive and simple way is indicated.

Mechanism for specificity by HMG-1 in enhanceosome assembly.

Assembly of enhanceosomes requires architectural proteins to facilitate the DNA conformational changes accompanying cooperative binding of activators to a regulatory sequence. The architectural protein HMG-1 has been proposed to bind DNA in a sequence-independent manner, yet, paradoxically, it facilitates specific DNA binding reactions in vitro. To investigate the mechanism of specificity we explored the effect of HMG-1 on binding of the Epstein-Barr virus activator ZEBRA to a natural responsive promoter in vitro. DNase I footprinting, mutagenesis, and electrophoretic mobility shift assay reveal that HMG-1 binds cooperatively with ZEBRA to a specific DNA sequence between two adjacent ZEBRA recognition sites. This binding requires a strict alignment between two adjacent ZEBRA sites and both HMG boxes of HMG-1. Our study provides the first demonstration of sequence-dependent binding by a nonspecific HMG-box protein. We hypothesize how a ubiquitous, nonspecific architectural protein can function in a specific context through the use of rudimentary sequence recognition coupled with cooperativity. The observation that an abundant architectural protein can bind DNA cooperatively and specifically has implications towards understanding HMG-1's role in mediating DNA transactions in a variety of enzymological systems.

18.3: Implementation of a New Wide Viewing Angle Mode for TFT‐LCDs

AbstractCompare to the conventional twisted nematic (TN) mode TFT‐LCD fabrication process, so far suggested method for the wide viewing angle modes require extra mask‐counts. Patterning of the color filter common electrode to achieve the multi‐domain vertical alignment (VA) mode costs additional process step. In addition, to avoid improper disclinations, strict alignment margin is necessary. Enhanced vertical alignment (EVA) mode has been developed where the multi‐domain cell is formed by the interaction between fringe fields of the pixel electrodes and protrusions on the TFT‐array panel. Compared to the TN‐mode, since the common electrode is not patterned, EVA mode does not require any additional mask‐count. Using the combinations of multi‐layer overlap patterns with gate metal, gate dielectrics, passivation nitride, and source/drain metal, protrusions can be formed during the normal TFT‐array fabrication process. Viewing angle of the EVA mode can even surpass other wide viewing modes.

Accurate overlaying for mobile augmented reality

Mobile augmented reality requires accurate alignment of virtual information with objects visible in the real world. We describe a system for mobile communications to be developed to meet these strict alignment criteria using a combination of computer vision, inertial tracking and low-latency rendering techniques. A prototype low-power and low-latency renderer using an off-the-shelf 3D card is discussed.

A novel electrostatic slanted-grid-type ion spectrometer and the development and characterization of semiconductor ion detectors

Abstract A new slanted-grid-type ion-energy spectrometer has the following uniaue characteristic properties: (i) This spectrometer has the capability of a complete separation of ions from X-rays, neutral particles and electrons. (ii) No use of magnetic fields means no disturbances of ambient plasma-confinement magnetic fields. (iii) Its simple single-channel collector plate for “energy-derivative” direct spectrum measurements does not reauire its strict alignment. Furthermore, upgraded semiconductor ion detectors are developed for the purpose of plasma-ion-energy analyses in a wideion-energy range from only a few hun-dred eV to several tens of keV. The responses of these detectors are investigated using a test-ion-beam line. The ion-energy spectrometer using the semiconductor detector as a collector is demonstrated to have a signal-to-noise ratio of 2–3 orders of magnitude better than ion spectrometers using metal-collector detectors without the effects of X-rays and electrons from plasmas.

98/02922 Geomechanical considerations for coal combustion byproducts in engineering applications

Ultrasonic techniques are used to characterize the anisotropic and nonlinear elastic behavior of wood and rock and to interrogate the structural properties of these materials. For elastic anisotropy two types of experiments are performed, namely qP-wave velocity measurements on spherical samples in about 100 directions of propagation rather regularly sampled in space, together with S-wave birefringence measurements in a few directions on additional samples. For nonlinear elasticity, acoustoelastic experiments were conducted, consisting in P and S-wave velocity measurements under controlled confining pressure. The experimental results show that wood exhibits much larger elastic anisotropy, but much weaker elastic nonlinearity than rock. For instance, the deviations from isotropy in wood can reach 70%, whereas in rock, typically, it can hardly exceed 20%. In contrast, regarding nonlinearity the increase of P or S-wave moduli per unit confining pressure in wood is always smaller than 30, in the radial direction, or 10, in the longitudinal and transversal directions, whereas it can reach roughly one to a few hundreds in rock.These contrasted behaviors can be simply explained by structural considerations. Thus, the exceptionally strong elastic anisotropy of wood is due to the strict structural alignment of its constituents, that is to say to the preferential orientation of the anatomical elements (tracheids, fibers, ray cells, vessels etc.) for ‘textural’ anisotropy, and to the cellular wall organisation for ‘microstructural’ anisotropy. In comparison, rock only exhibits a rough statistics of the orientation distribution function of its constituents, mainly the grain minerals, the pores and the cements. In contrast, the strinkingly strong nonlinear elastic response of rock, a wellestablished classical observation, is due to the presence of compliant mechanical defects (cracks, microfractures, grain-joints etc.). Such features are practically nonexistent in wood which explains its weak nonlinear response.

Dynamic elastic anisotropy and nonlinearity in wood and rock

Ultrasonic techniques are used to characterize the anisotropic and nonlinear elastic behavior of wood and rock and to interrogate the structural properties of these materials. For elastic anisotropy two types of experiments are performed, namely qP-wave velocity measurements on spherical samples in about 100 directions of propagation rather regularly sampled in space, together with S-wave birefringence measurements in a few directions on additional samples. For nonlinear elasticity, acoustoelastic experiments were conducted, consisting in P and S-wave velocity measurements under controlled confining pressure. The experimental results show that wood exhibits much larger elastic anisotropy, but much weaker elastic nonlinearity than rock. For instance, the deviations from isotropy in wood can reach 70%, whereas in rock, typically, it can hardly exceed 20%. In contrast, regarding nonlinearity the increase of P or S-wave moduli per unit confining pressure in wood is always smaller than 30, in the radial direction, or 10, in the longitudinal and transversal directions, whereas it can reach roughly one to a few hundreds in rock. These contrasted behaviors can be simply explained by structural considerations. Thus, the exceptionally strong elastic anisotropy of wood is due to the strict structural alignment of its constituents, that is to say to the preferential orientation of the anatomical elements (tracheids, fibers, ray cells, vessels etc.) for ‘textural’ anisotropy, and to the cellular wall organisation for ‘microstructural’ anisotropy. In comparison, rock only exhibits a rough statistics of the orientation distribution function of its constituents, mainly the grain minerals, the pores and the cements. In contrast, the strinkingly strong nonlinear elastic response of rock, a wellestablished classical observation, is due to the presence of compliant mechanical defects (cracks, microfractures, grain-joints etc.). Such features are practically nonexistent in wood which explains its weak nonlinear response.

Lack of a requirement for strict rotational alignment among transcription factor binding sites in yeast

The MF alpha 1 gene of Saccharomyces cerevisiae is an alpha specific gene whose expression is regulated by two upstream activation sites (UASMF alpha 1S), which are the binding sites for activator proteins, MAT alpha 1 and MCM1. UASMF alpha 1 elements act in a synergistic fashion; lack of either element causes reduced expression levels that are 6- to 45-fold less than that of intact promoter in alpha cells. We investigated the effect of manipulating rotational alignments among transcription factor binding sites of MF alpha 1 on the expression of the gene. The expression level of MF alpha 1 decreased with the spacing between the two UASMF alpha 1S and no synergism was observed when the distance of the two elements was longer than 90 base pairs. No strict rotational alignment was required for their synergistic action. We also show that the spacing between UASMF alpha 1 elements and TFIID binding site, the TATA box, had little, if any, effect on MF alpha 1 expression. We chose a sufficient number of positions for UASMF alpha 1S to ensure that, in several of these positions, MAT alpha 1 and MCM1 were on the opposite side of the DNA helix with respect to the TATA box.

An interplanetary planar magnetic structure oriented at a large (∼ 80 deg) angle to the Parker spiral

Magnetic field structures in the solar wind, characterised by a variation of the field vectors within a plane inclined to the ecliptic (‘Planar Magnetic Structures’, PMS's), were reported recenty (Nakagawa et al., 1989). These PMS's have the property that the plane of variation of the field also contains the nominal Parker spiral direction. We report here an observation of a PMS where the direction of the line of intersection of the plane of field variation with the ecliptic plane makes a large (∼80 deg) angle to the Parker spiral direction. Furthermore, the angular variables of the field, θB(elevation) and φB (azimuth) (a) vary over a restricted range, and (b) are linearly related. We show the latter property to be related to the former. We argue that currently proposed models for the origin of PMS's, in as much as they require field configurations which retain strict alignment with the Parker spiral direction from formation to observation, are probably incomplete.

No strict alignment is required between a transcriptional activator binding site and the "TATA box" of a yeast gene.

GAL4 is a transcriptional activator of the galactose metabolism genes in the yeast Saccharomyces cerevisiae. We show that GAL4 expressed in yeast activated transcription equally well when a single GAL4 binding site was placed at any of nine positions upstream of the GAL1 (galactokinase gene) "TATA box." We chose a sufficient number of positions for the binding site to ensure that, in several of these positions, GAL4 was on the opposite side of the DNA helix with respect to the TATA box. Smaller GAL4 derivatives were similar to wild-type GAL4 in that they also activated transcription in a manner independent of the side of the DNA helix they bound with respect to the TATA box. Unlike wild-type GAL4, however, these smaller GAL4 derivatives activated transcription better when we placed a binding site progressively closer to the TATA box over a distance of 34 base pairs.

人工しつ関節置換の手術技法の工夫 Ｉ／Ｂ ｔｏｔａｌ ｃｏｎｄｙｌａｒ ｋｎｅｅ型に関して

For the knee with severe pain and deformity, the total knee replacement may be one of the most effective therapy. To obtain fine results and to prevent the future migration and loosening of implants, this operation demands exact correction of the alignment of the lower limb.Some scales are designed to catch mechanical axis of thigh and lower leg. One is a staple shaped acrylic scale with buried wires at every 1cm. The position of the femoral head can be detected in a preoperative roentgenogram with this scale. Another is an isosceles triangle scale with a slit in the base. In the thigh, a bisector to the base is adjusted to the femoral mechanical axis in the coronall plane from the head to the center of condyles, and in the lower leg, to the tibial axis from the center of the tibial plateau to the center of condyles of the ankle respectively, and the bone cut is done through the slit of the base. By these scales and several techniques with this operative procedure, we are able to perform precise correction of the alignment under the direct visual orientation.In 26 joints of 22 patients, using I/B total condylar knee system, 25 joints showed strict alignment and their clinical results were good.

The structure and composition of the eggshell and embryonic membranes of Alligator mississippiensis

SummaryThe structure and chemical composition of the eggshell and eggshell membrane of Alligator mississippiensis were investigated utilizing macroscopy, scanning electron microscopy, energy dispersive analysis by X‐rays, atomic absorption flame spectroscopy and spectrographic techniques on age known eggs fixed at daily intervals throughout the 65‐day incubation period. Macroscopic observations were also made on the structure and disposition of the extraembryonic membranes. The freshly laid alligator egg is pure white and translucent. Within 24 h of egg‐laying the embryo attaches to the top of the egg, so inducing an opaque, chalky white, central band. As incubation progresses, this band expands in length, eventually reaching the ends of the egg by about the fifth week of development. The origin and expansion of eggshell banding are multifactorial, being caused by: (1) a drying out of the eggshell due to polarization of the watery albumen towards the ends of the egg and an increase in porosity of the shell; (2) the numerous pores in the central region of the shell which render the calcite opaque; (3) the development of erosion craters which render the calcite opaque and alter the optical properties of the shell; (4) the presence of fewer mammillae at the ends of the egg; (5) a progressive decrease in the ratio of calcite crystals to organic matrix in the organic layers; and (6) the expansion of the vascular chorio‐allantoic membrane around the inside of the shell which mobilizes minerals from the latter (for use in embryonic calcification), so causing the eggshell membrane to become chalky white. The alligator egg consists of the following layers from outside in: (1) an outer densely calcified layer (100–200 μm thick) consisting of small vertically stacked calcite crystals orientated with their crystallographic c axes at right angles to the shell surface; (2) a honeycomb layer (300–400 μm thick) consisting of horizontally stacked calcite crystals with their crystallographic c axes parallel to the shell surface; (3) an organic layer (approximately 10 μm thick) containing a higher percentage of organic matrix to calcite crystals, and through which the shell cleaves and falls away from the egg shortly before hatching; (4) a mammillary layer (20–30 μm thick) which is more pronounced in the central opaque region of the shell and which attaches the latter to the eggshell membrane; and (5) an eggshell membrane (150–250 μm thick) consisting of an interwoven mesh of fibres, separated from the albumen by an amorphous limiting membrane, in which there are numerous pores. The crystals of the outer densely calcified layer undergo extrinsic acidic dissolution (by organic acids produced by nest micro‐organisms and by hydrated carbon dioxide) to produce erosion craters and cratered pore orifices. The extent, shape and depth of these craters is governed by the strict crystallographic alignment of calcite crystals in the outer densely calcified and honeycomb layers, by the anisotropic properties of these crystals and by diffusion control. These erosion craters expose at their broad bases the underlying honeycomb layer which contains large numbers of vesicular holes, interconnecting with other cavities throughout the shell. Thus, development of erosion craters renders the entire egg more porous as incubation proceeds. In addition, these craters, together with the mobilization of calcite crystals out of the organic layer for use in embryonic mineralization, progressively weaken the shell causing it to crack and cleave off the eggshell membrane and mammillary layer, so facilitating hatching. No air space is present in the alligator egg, neither are there any chalzae. The embryo has the usual amniote arrangement of extra‐embryonic membranes which are firmly fused along two longitudinally opposite ribs, so anchoring the embryo in a constant position within the shell. The structure of the alligator egg is beautifully adapted to both its function and the nesting biology of the animal. The present investigation documents for the first time in any animal: (1) extrinsic degradation of an eggshell as incubation progresses; (2) a gross change in the external appearance of an egg as development proceeds; (3) two types of shell structure (mammillae plus pores, no mammillae no pores) within different regions of the same egg; and (4) a marked change in the porosity of an egg as incubation proceeds.

Oriented glass ceramic fibre

LONGITUDINAL velocity gradients in a flowing system have a powerful orienting influence on macromolecules and have been used to align polyethylene chains immediately before crystallisation1 and from the melt2. Corning 119 SCR is a glass which crystallises to a glass ceramic containing fluorophlogopite (mica) as the principal crystalline phase. By subjecting it to pure extensional flow during crystallisation, strict alignment of the fluorophlogopite crystals has been achieved. Once produced, the alignment is maintained during subsequent drawing down to fibre diameters of less than 100 µm.

QUATERNAKY VOLCANISM ON SUMATRA

The eruption of vast quantities of acid pumice tuffs stands out as the major event in the initial stages of Quaternary volcanism on Sumatra. By their strict alignment along a trend of longitudinal fault-trough systems, which follow the entire length of the island and cut through Mesozoic as well as Miocene fold belts, these rhyolitic volcanics strongly suggest that they are sheetlike deposits of paroxysmal fissure eruptions emptying magma chambers in an advanced stage of differentiation. During settling, the erupted material has evidently been similar to fiery clouds (“nuees ardentes”) of the Katmai type. Enormous gas pressures, gradually developed in the vault spaces of the original magma reservoirs, account for the sudden disrupture of the overlying roof portions along pre-existing lines of structural weakness. As contrasted with later andesitic volcanism, these outbursts built up no central cones, but rather extensive sheets with plateau-like surfaces. In the Lake Toba and Pasoemah1 Highland rhyolite tuffs, the volcanic sheets appear to consist, in at least their lower portions, of welded tuffs with columnar structures bearing all characteristics, both macroscopic and microscopic, of the New Zealand ignimbrites. In extreme southern Sumatra, however, they are simply deposits of loose pumice tuffs, whereas similar rocks in the Padang Highlands in Central Sumatra still await further investigation. At many places acid lavas of about the same age, and still preserved as partly mineralized rhyolitic plugs, rose along the same or adjacent channelways in South and Central Sumatra. Later dacitic to andesitic, and in isolated cases also basaltic, volcanism built up central cones above longitudinal as well as prominent transverse faults or fissures. Basaltic lavas resembling true plateau basalts were poured out on the surface of the rhyolite tuffs in a limited area near Soekadana in eastern South Sumatra, well beyond the zone of Miocene orogenesis of the western coast ranges. Repeated eruptions of acid pumice tuffs along the same longitudinal graben trends interrupted the andesitic period at the time of the great pre-historic Lake Ranau eruption in western South Sumatra, and, comparatively recently, at the occasion of the famous 1883 Krakatau pumice eruption, which apparently took place at the intersection of the submarine continuation of the Semangka graben in South Sumatra and an important transverse fault. Another young Quaternary explosion produced the acid block tuffs around the Pilomasin basin about 60 km northeast of Lake Ranau. The trend of differentiation of Quaternary Pacific magma types on the Sumatran mainland is almost duplicated within the limited space of the various magma types of the Krakatau island group with its basaltic to rhyo-dadtic lavas and tuffs; the extremely acid effusiva of Sumatra, however, are without equivalents.