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To meet the increasing demand for air transportation, Ministry of Land, Infrastructure and Transport had carried out the offshore extension project at Tokyo International Airport (Haneda Airport). The airport should be constructed to be perfectly level, but the ground conditions with very thick layers of super soft dredged soils and need for reclamation made the task very difficult. Because of large amount of consolidation settlement, ground improvement by combined vertical drain method was applied to decrease residual and differential settlement after opening of new airport. This paper is aimed to introduce the design concept and method of ground improvement for this project. In addition the result of ground improvement is keeping satisfactory performance for operating airport confirmed by long-term monitoring for airport facilities. [ABSTRACT FROM AUTHOR]

The two key impediments to addressing the ageing crisis of Japan are: electoral politics which avoid making hard decisions painful to voters (especially the hiking of the consumption tax), and even more insidious, the norms of Japanese corporations and patriarchal society which discourage women from marrying and producing babies while holding onto a career and aspirations of their own. If Japan’s ageing problem were to persist in the long run, then a concomitant decline in its manufacturing capacity (which underpins its export-dependent economy) and a diminution of its political weight in its international affairs can be anticipated. [ABSTRACT FROM AUTHOR]

Morphological variation in current-year shoots within plants was examined in five deciduous and four evergreen liana species from temperate forests in Japan to elucidate the role differentiation in shoots. All lianas had both shoots that twined or developed adventitious roots to gain support on host materials (searcher shoots) and self-supporting shoots with no climbing structures (ordinary shoots). Searcher shoots were 20–295 times longer than ordinary shoots. The allometric relationships between stem length and leaf area differed between searcher and ordinary shoots, and the stem length for a given leaf area was greater in searcher shoots. Leaf area per shoot mass was 1.4–4.3 times higher in ordinary shoots because of the greater allocation to leaf biomass. Searcher shoots comprised only 1–6% of total shoots but 30–85% of total shoot length in deciduous lianas. Ordinary shoots accounted for 70–95% of the total leaf area in these liana species. These results suggest that the exploration of new space was primarily achieved by searcher shoots, whereas a large proportion of current photosynthetic production was achieved by ordinary shoots. The range of stem length and leaf mass ratio of ordinary shoots was similar to that in shoots of tree species. Specialization of shoots in lianas is discussed. [ABSTRACT FROM AUTHOR]

The use of parametric and multi-objective optimization (MOO) as a new way of approaching architectural design has been growing in line with current breakthroughs in computational architecture. Wood, on the other hand, is a living and unique building material that provides durability, manufacturing flexibility, and local availability. One of the structure types that provides high structural stability is the hyperboloid. However, the exploration of hyperboloid structures in building design, together with the building daylight objective, is still limitedly reported. This paper presents the application of the parametric approach and multi-objective optimization in optimizing the structure and daylight objectives of a hyperboloid two-story wooden house in Japan, made of 105 mm × 105 mm × 4000 mm Japanese timber. The method involves iterating dynamic parameters such as radius bottom, offset distance, timber members, twisting level, building height, radius-top, and roof slope to optimize the structural objective of minimizing normal force average, displacement, and cost while simultaneously maximizing building volume. Regarding daylight objectives, unit movement and glazing ratio that control the glazing strategies were explored to optimize useful daylight illumination (UDI) in summer and winter. The optimization and exploration yielded 10,098 solutions in structural analysis and 406 solutions in daylight exploration. Based on the data analysis, the proposed methodology has successfully produced the best design solution, discovering the balance between the objective trade-offs. In addition, the most influential parameter that shapes the value of design objectives has been identified. The findings of this research were expected to contribute to and enhance the performance-based design optimization, and support design decision-making process in the early design stage of a wooden house with a hyperboloid structure. [ABSTRACT FROM AUTHOR]

Little is known about the population structure of social microorganisms, yet such studies are particularly interesting for the ways that genetic variation impacts their social evolution. Dictyostelium, a eukaryotic microbe widely used as a developmental model, has a social fruiting stage in which some formerly independent individuals die to help others. To assess genetic variation within the social amoeba Dictyostelium purpureum, we sequenced ∼4000 base pairs of ribosomal DNA (rDNA) from 37 isolates collected in Texas, Virginia, and Japan. Our analysis showed extensive genetic variation between populations and clear evidence of phylogenetic structure. We identified three major phylogenetic groups that were more different than other accepted species pairs. Tests using pairs of clones showed that both sexual macrocyst and asexual fruiting body formation were influenced by genetic divergence. Macrocysts were less likely to form between pairs of clones from different groups than from the same group. There was also a correlation between the genetic divergence of a pair of clones and their degree of mixing within fruiting bodies. These observations suggest that cryptic species might occur within D. purpureum and, more importantly, reveal how genetic variation impacts social interactions. [ABSTRACT FROM AUTHOR]

The article focuses on the use of high-performance steels for the construction of bridge in Japan and presents examples of their application. To increase the competitiveness of steel bridges against concrete, to improve safety, and to respond to demands for the reduction of costs, the use of high-performance bridge steel is predicted to be further developed and used. Several tables and graphs showing the names, properties and codes of high performance steels as of April 2004 are presented.

We compared tree architecture and allometry among five Symplocos species ( Symplocos myrtacea, Symplocos lancifolia, Symplocos lucida, Symplocos glauca, and Symplocos theophrastiifolia) in a Japanese warm-temperate forest to understand the causes of interspecific variations in these characteristics. S. lancifolia, S. glauca, and S. theophrastiifolia grew at elevations below 500 m, whereas S. lucida grew on ridges irrespective of elevations, and S. myrtacea grew at elevations above 590 m. The species that shared a habitat exhibited trade-offs between height growth and crown area extension that might reflect differentiation in their regeneration niches. S. lancifolia showed the lowest height growth and widest crown extension, whereas S. theophrastiifolia showed the greatest height growth and lowest crown extension. S. glauca was intermediate between these species. S. lucida grows on ridges characterized by strong winds and the absence of other Symplocos species; it had the thickest stem and second-narrowest crown of the five species, possibly due to mechanical stability constraints. S. myrtacea was smallest at the onset of reproduction, and its fruits developed under closed canopies. Its architecture and allometry may increase seed production. Variation in tree architecture and allometry among the five species appear to be related to differentiation among regeneration niches, mechanical stability, and reproduction constraints. [ABSTRACT FROM AUTHOR]

As part of the 2007 Tri-Center Field Mission to Japan, a reconnaissance team comprised of fourteen graduate students and three faculty members from three U.S. earthquake engineering research centers, namely, Multidisciplinary Center for Earthquake Engineering Research (MCEER), Mid-America Earthquake Center (MAE), and Pacific Earthquake Engineering Research Center (PEER), undertook a reconnaissance visit to the affected area shortly after the 2007 Niigata-Chuetsu Oki earthquake. This mission provided an opportunity to review the nature of the earthquake damage that occurred, as well as to assess the significance of the damage from an educational perspective. This paper reports on the seismological characteristics of the earthquake, preliminary findings of geotechnical and structural damage, and the causes of the observed failures or collapses. In addition, economic and socio-economic considerations and experiences to enhance earthquake resilience are presented. [ABSTRACT FROM AUTHOR]

The Median Tectonic Line (MTL) is a first-order tectonic boundary that separates the Sanbagawa and Ryoke Metamorphic Belts. Strike-slip movements on the MTL have been well documented by many workers. New field based structural studies in the Sanbagawa Belt close to the MTL reveal a large number of secondary faults and semibrittle shear bands indicating a top-to-the-north normal sense of displacement. The strikes of these shear zones and their spatial distributions suggest that development of these structures is related to movements on the MTL. These results imply that the MTL has a large-scale normal shear component on a regional scale that can help account for the exhumation of the Sanbagawa Belt. Our proposed history of the MTL can also account for changes in the geometry of folds in the Sanbagawa Belt. [ABSTRACT FROM AUTHOR]

The escalation of defensive/offensive arms is ubiquitous in prey-predator evolutionary interactions. However, there may be a geographically varying imbalance in the armaments of participating species that affects the outcome of local interactions. In a system involving the Japanese camellia (Camellia japonica) and its obligate seed predator, the camellia weevil (Curculio camelliae), we investigated the geographic variation in physical defensive/offensive traits and that in natural selection on the plant's defense among 17 populations over a 700-km-wide area in Japan. The sizes of the plant defensive apparatus (pericarp thickness) and the weevil offensive apparatus (rostrum length) clearly correlated with each other across populations. Nevertheless, the balance in armaments between the two species was geographically structured. In the populations for which the balance was relatively advantageous for the plant's defense, natural selection on the trait was stronger because in the other populations, most plant individuals were too vulnerable to resist the attacks of the weevil, and their seeds were infested independent of pericarp thickness. We also found that the imbalance between the defensive/offensive armaments and the intensity of natural selection showed clear latitudinal dines. Overall, our results suggest that the imbalance of armament between sympatric prey and predator could determine the strength of local selection and that climatic conditions could affect the local and overall trajectory of coevolutionary arms races. [ABSTRACT FROM AUTHOR]

Japan has twenty years of experience in designing and constructing base-isolated building structures. Construction has increased significantly since the 1995 Hyogoken-Nanbu (Kobe) earthquake, having reached over 150 annual construction projects. Many new developments and refinements have been made in the material, device, design, and construction of these structures. This paper summarises recent design and construction of base-isolated building structures in Japan, including statistical data with respect to the common usage as well as the number of new projects. It is notable that the size, height, and fundamental natural period of new base-isolated buildings increase steadily with time, indicating that base-isolation in Japan is reaching maturity. Base-isolators and dampers commonly adopted in Japan are also introduced, with emphasis on recent design efforts to enlarge the natural period of base-isolated structures and reduce the lateral forces induced in the superstructure. Basic design procedures are presented, including determination of design earthquake forces, modelling of base-isolation layers, modelling of the superstructure, selection of ground motions, time-history analyses, and performance criteria. A mandated peer-review system, unique for design of base-isolated structures, is also noted. Several characteristic issues in the design of base-isolated structures are discussed: Variation of base-isolation material properties, applications to high-rise buildings, effects of vertical ground motions, and response when subjected to near-fault ground motions. [ABSTRACT FROM AUTHOR]

This paper presents the current state of the art of nonlinear analysis of steel-concrete composite structures. The focus is on frame elements, which are computationally faster than continuum finite element models. First, section models are presented, with a review of resultant and fiber models and a discussion of possible practical applications. The presentation of frame elements follows. Models with lumped and distributed inelasticity, as well as models with perfect and partial connections are covered. Rigid and partially restrained joints are then reviewed and discussed at length. A discussion of the analysis of structural walls completes the presentation of the models. Modeling applications to the analysis of composite frames are also presented. This state-of-the-art review focuses on developments that have stemmed from the recently completed National Science Foundation sponsored U.S.-Japan program on composite and hybrid structures. [ABSTRACT FROM AUTHOR]

As part of the U.S.-Japan Cooperative Research Program on Composite/Hybrid Structures (1992), investigations were carried out at the University of Nebraska-Lincoln and University of Illinois, to develop moment connection details and accompanying design provisions for connecting steel beams to circular concrete filled tube (CFT) columns. This paper provides an overview of the work carried out. Work at the University of Illinois consisted of evaluating the inelastic response of six possible connection details. Six large-scale connections were tested to failure using the quasi-static test method. Connections welded to the skin of the tube created large distortions of the tube wall, and were susceptible to weld, flange, or tube wall fracture. External diaphragm and continuous web details exhibited more favorable inelastic behavior, but the flexural strength of these connections began to deteriorate relatively early in the imposed deformation history. Continuing the flanges through the composite column showed adequate strength, however due to excessive slipping this connection did not dissipate significant inelastic dynamic energy. One of the details tested at the University of Illinois was passing the girder section through the CFT columns. This through beam detail provided the most effective detail to achieve the ideal rigid connection condition. Work at the University of Nebraska-Lincoln concentrated on comprehending the behavior of the through beam connection detail. The behavior of CFT columns under seismic loads was studied through testing six columns which were subjected to a constant axial load in addition to a cyclic lateral load. Failure modes for through beam connection detail were identified through testing seven, two-thirds scale connection specimens. These tests were used to comprehend the force transfer mechanisms between steel beams and CFT columns and develop design provisions that could estimate the capacity of the various elements of the through beam connection detail. [ABSTRACT FROM AUTHOR]

In the design of beam-to-column subassemblies in concrete-filled steel tubular column systems, a design formula established by the Architectural Institute of Japan (AIJ) is applied. However, in the current AIJ standard, the scope of the design formula is limited to ordinary material strengths; i.e. up to an unconfined compression strength of 36 MPa for concrete and tensile strength of 490 MPa for structural steel tubes. So, the effect of higher material strengths on subassembly behavior is studied in this investigation. The experimental results presented in this paper verified that the above-mentioned AIJ design formula is applicable up to an unconfined compression strength of 110 MPa for concrete and tensile strength of 809 MPa for structural steel tubes. An analytical model for the restoring force characteristics of the shear panel in the subassemblies was also proposed, and was found to reproduce the experimental results with good accuracy. [ABSTRACT FROM AUTHOR]

This report outlines the rolling stock of "Shinkansen" and conventional "narrow-gauge" railways, and reviews the research and development to put railway vehicles into revenue service from the viewpoint of rolling stock dynamics in Japan. [ABSTRACT FROM AUTHOR]

To characterize the clinical features associatedwith XLRS1 gene mutations in Japanese patients with X-linked juvenileretinoschisis (xlRS), we evaluated the following data on 14 Japanese malesfrom 13 unrelated families with XLRS1 mutations: age and symptomsat first visit to an ophthalmologist and ophthalmologic findings includingvisual acuity, refractive errors, fundoscopic appearance, and results of electroretinography(ERG) and electro-oculography (EOG). Each clinical finding was reviewed whenthe patients were between six and eight years of age. The best-corrected visualacuity in 12 patients (24 eyes) between the ages 6 and 8 years ranged from1.0 to no light perception. Macular abnormalities were present in all cases.Peripheral retinoschisis was present in 14 of 26 eyes (53.8%). In the 21 eyesfor which a single-flash ERG had been recorded, b-wave amplitude was reducedin 17 eyes. The EOG showed a low Arden ratio in three of the 13 eyes in theseven patients evaluated. No clear relationship was observed between the clinicalfeatures and the existing mutations. Three of four patients with a visualacuity less than 0.1 had retinal detachment or severe macular lesion thathad occurred before the age of four years. Two patients harbored deletionsof exon 1 or of the boundary region between exon 3 and intron 3, and one patientharbored R182C in exon 6. The present study shows a heterogeneity of mutationsin the XLRS1 gene and phenotypic variations in 14 Japanese patientswith xlRS. [ABSTRACT FROM AUTHOR]

Presents a study which discussed the similarities and differences in steel moment frames for seismic design between the United States and Japan. Details on the effect of earthquake to the frames in Japan; Conclusions.

Examines the lessons learned from the Hanshin-Awaji earthquake in Japan on January 17, 1995. Classification of the earthquake; Peculiar phenomena under which the earthquake occurred; Effects of the earthquake from ordinary ones coming from a seismic source; Proposal to use the longitudinal stress wave analysis method.

Provides information on a study which discussed fire-safe design methods for construction in Japan incorporating the application of fire-protection materials. Description of the fire-protection materials targeted in the study; Fire-safe design model using an office building; Structural stability of frames at high temperature.

Discusses the passage from educational institution to employment enterprise among two groups of male employees at a small manufacturing company in Tokyo, Japan. Literature on the nature of Japanese education system; Case of the Shintani Metals Co.

The article looks at the stance of the Japanese and Soviet Union governments concerning the islands off the northeast coast of Hokkaido, Japan, which the Russians seized in the last days of World War II. It presents information on the wars fought by each country against each other. It discusses the reasons for Japan's pessimism over the chances for first Soviet and now Commonwealth political development. It compares the contradiction between the principle and reality in Japan's relations with Russia with Japan's self-defense policy.

Focuses on `Enola Gay' exhibition at the Smithsonian Institution in Washington, D.C. Public presentation of history; Issue on responsible scholarship; Controversies surround the exhibition; Exhibition script; Planning strategies; Social contests and human implications of the aviation and space experiences.

The 2008 Wenchuan-China earthquake showed the importance of considering the bidirectional seismic action as a cause of failure in column hinge mechanisms. Subsequently, the large 2011 Tohoku-Japan earthquake revealed that Special Moment Frames buildings, made of tubular columns (Hollow Structural Section or Built-up Box Section) and rigid connections with I-beams, did not suffer serious damage. However, only the ConXtech® ConXL™ moment connection has been prequalified according to the (American Institute of Construction) AISC Seismic Provisions for use with tubular columns and the rest of connections do not consider biaxial resistance. The research reported herein investigated the cyclic response of box-columns joints, connected to I beams using the four-bolt extended endplate connection, subjected to bidirectional bending and axial load on the column. To conduct the study, complex nonlinear finite element models (FEMs) of several I beam to box column joint configurations were constructed and analyzed under cyclic loading using the ANSYS software. The results reveal that the failure is concentrated in the beams of all joint configurations except for the columns with axial load equal to 75% of the column capacity, where a combined failure mechanism is achieved. The energy dissipation capacity of joints with a greater number of beams is lower than joints with fewer beams. The bidirectional effect of the seismic action and the level of axial load must be considered to avoid the formation of a column-hinge fragile failure mechanism also the behavior exhibited by 3D joints is more realistic than 2D joints according to real structures. [ABSTRACT FROM AUTHOR]

The 30 May 2015 M w 7.9 Bonin Islands earthquake, Japan, is one of the largest deep‐focus earthquakes ever recorded. Its occurrence, close to 700‐km depth, in an area without any known historical seismicity, along with its magnitude, was a surprise to scientists. Deep earthquakes are generally believed to have few aftershocks and no foreshocks. Here, we explore the earthquake productivity in the hypocentral surroundings and detect 49 not previously identified earthquakes, 28 of which occurred during an accelerating preseismic phase that started 3 months prior to the main shock. This is the first time that such foreshock activity has been observed for a deep earthquake. The preseismic and postseismic activity suggests transformational faulting within a metastable olivine wedge (MOW) inside the slab at depth as the triggering principal mechanism for this deep earthquake sequence, the seismicity starting where the backward bending of the subducting Pacific plate is maximum. Plain Language Summary: Deep earthquakes have been puzzling seismologists for almost a century, since their discovery in the 1920s. Earthquakes deeper than 50 km represent about 25 % of the global seismicity, and deep‐focus earthquakes are defined as those located at 300‐km depth or more. They can be exceedingly large and occur at temperatures and pressures where sliding and fracture are inhibited, thus the brittle fracture/friction mechanism, valid in Earth's crust, cannot hold. Despite their abundance, the physical mechanism behind deep‐focus earthquakes is still a subject of ongoing debate. The Bonin Islands earthquake (30 May 2015, M w7.9) occurred at 680‐km depth in a previously quiet area. In order to better understand why and how it occurred there, we searched for previously unknown earthquakes in the surroundings. For the first time, we identify a preseismic phase preceding such a very deep‐focus earthquake. The location of the newly detected earthquakes reveals the geometry of the slab at depth, and their spatiotemporal distribution supports transformation of metastable olivine as the rupture initiation process. Key Points: We present the first evidence of intense foreshock activity before a deep‐focus earthquake49 newly detected EQs reveal slab geometry and the possible existence of metastable olivine wedge at depthWe find a low productivity aftershock sequence that follows Omori's law [ABSTRACT FROM AUTHOR]

We applied tomographic inversion and receiver function analysis to seismic data from ocean-bottom seismometers and land-based stations to understand the structure and its relationship with slow slip events off Boso, Japan. First, we delineated the upper boundary of the Philippine Sea Plate based on both the velocity structure and the locations of the low-angle thrust-faulting earthquakes. The upper boundary of the Philippine Sea Plate is distorted upward by a few kilometers between 140.5 and 141.0°E. We also determined the eastern edge of the Philippine Sea Plate based on the delineated upper boundary and the results of the receiver function analysis. The eastern edge has a northwest–southeast trend between the triple junction and 141.6°E, which changes to a north–south trend north of 34.7°N. The change in the subduction direction at 1–3 Ma might have resulted in the inflection of the eastern edge of the subducted Philippine Sea Plate. Second, we compared the subduction zone structure and hypocenter locations and the area of the Boso slow slip events. Most of the low-angle thrust-faulting earthquakes identified in this study occurred outside the areas of recurrent Boso slow slip events, which indicates that the slow slip area and regular low-angle thrust earthquakes are spatially separated in the offshore area. In addition, the slow slip areas are located only at the contact zone between the crustal parts of the North American Plate and the subducting Philippine Sea Plate. The localization of the slow slip events in the crust–crust contact zone off Boso is examined for the first time in this study. Finally, we detected a relatively low-velocity region in the mantle of the Philippine Sea Plate. The low-velocity mantle can be interpreted as serpentinized peridotite, which is also found in the Philippine Sea Plate prior to subduction. The serpentinized peridotite zone remains after the subduction of the Philippine Sea Plate and is likely distributed over a wide area along the subducted slab. [ABSTRACT FROM AUTHOR]

This manuscript reviews seismic isolation and response control methods of buildings, which are able to make buildings resilient against earthquakes and have become popular during the last three decades in Japan. Seismic isolation is a method of protecting a building from major earthquakes by installing isolators and energy absorbing devices under the superstructure. The manuscript describes three types of laminated rubber bearings and three kinds of damping devices. Seismic isolation provides not only structural safety, but also safety and security for people and properties in the building. Seismic isolation is also used for the retrofit of historic buildings. Response control methods utilize various kinds of dampers that are installed into a building and absorb vibration energy. The manuscript explains three foremost response control dampers: the steel hysteretic damper, the viscoelastic damper and the viscous fluid damper. The effects of seismic isolation and response control methods were verified through shaking table tests, structural health monitoring and earthquake response analyses. [ABSTRACT FROM AUTHOR]

This article discusses the United States-Japan Cooperative Earthquake Research Program which began in the year 1979, and its overall objective was to improve seismic safety practices in both countries. First four phases of the program were reinforced concrete (RC) structures, steel structures, masonry structures, and precast concrete structures. The program contents were based on a number of technical meetings of the United States and Japan planning groups and on the outcome of a joint planning group workshop held in Berkeley, California. The work carried out in the four groups is briefly described in the article. The concrete infill confined by the steel tubes provides increased axial stiffness and load capacity. The RCS systems are moment frames consisting of RC columns and steel beams. They provide excellent stiffness with RC columns and energy dissipation capacity through steel beams. RC/steel RC hybrid wall systems are also discussed.