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The pile bearing capacity varies even within the same site. This study aims to gain a better understanding of the effect of pile penetration techniques on the variability of bearing capacity. The study uses data from 83 jack-in test piles to explore the variations in penetration resistance at the pile head, base, and shaft. The semivariance increases with an increase of the horizontal distance, so we focus on the semivariance between 5 m range, whose error was defined as the error due to piling workmanship. The analysis shows that the errors follow a lognormal probability distribution, and the coefficient of variation (COV) in penetration resistance at the heads and bases is about 10%, while the COV in extracted resistance varies widely, with a range of 5–25%. Little difference in the variations due to piling workmanship was observed among different penetration motions, speeds, and soil types.

High-harmonic generation (HHG), which is the generation of light with multiple optical harmonics, is an unconventional nonlinear optical phenomenon beyond the perturbation regime. HHG, which was initially observed in gaseous media, has recently been demonstrated in solid-state materials. Determining how to control such extreme nonlinear optical phenomena is a challenging subject. Here, we demonstrate the control of HHG through tuning the electronic structure and carrier injection using single-walled carbon nanotubes (SWCNTs). We reveal systematic changes in the high-harmonic spectra of SWCNTs with a series of electronic structures ranging from a metal structure to a semiconductor structure. We demonstrate enhancement or reduction of harmonic generation by more than 1 order of magnitude by tuning the electron and hole injection into the semiconductor SWCNTs through electrolyte gating. These results open a path toward the control of HHG in the context of field-effect transistor devices.

Infrastructure has to be adequately planned, designed, executed and maintained to keep its structural performance over respective requirements throughout its life-cycle. However, infrastructure suffering from serious deterioration in structural members and subsequent loss in performance have been often found due to various reasons. To meet these facts, it is extremely important to pursue coordination of engineering work in the stages of design, execution and maintenance. The infrastructure management including the concepts of the life-cycle management and the asset management is an organized system to support engineering-based decision making for ensuring sufficient structural performance and long life of a structure at the design, execution, maintenance, and all related work during its life-cycle. This paper deals with infrastructure management system and an example of its application for a road bridge from seriously deteriorated.

The precise prediction of moisture variations within concrete is of great significance because various deterioration phenomena spanning corrosion to carbonation are induced by mass transfer facilitated by the presence of moisture. Under actual environmental conditions, concrete is exposed to numerous wetting and drying cycles. Thus, to accurately predict moisture variations it is essential to consider the effect of these conditions. This study investigates the effect of alternate wetting and drying cycles on moisture penetration through concrete at the mesoscale using a 3D discrete network model based on a Rigid Body Spring Model (RBSM). For modeling moisture transport during wetting, the non-linear diffusion equation is used and the effects of capillary suction in moisture transport are also considered. On the other hand, moisture transport during drying is modeled as an evaporation-diffusion process. The simulation results obtained using this discrete network model are validated against the available experimental outcomes. During the wetting cycle, the moisture content in regions close to the exposed surface rapidly increases and approaches the maximum saturation. The effect of subsequent drying is seen only until a certain depth below the exposed surface, known as the influential depth. It is also observed that moisture continues to penetrate deeper into a specimen even during a drying cycle.

Concrete breakout failures with acutely damaged concrete are one of the main problems caused by expansion anchors under tensile loading. In this study, the prevention of concrete breakout is investigated by post-installed reinforcement (PRs). Experimental and numerical studies were conducted to look into the effect of the PRs on the expansion anchors subjected to tensile loads. The 3D Rigid Body Spring Model (RBSM), which is based on discrete analysis at the mesoscale, was used as supporting numerical research. On pullout capacity, displacement, failure mechanism, and concrete breakout geometry, both experimental and numerical analyses were undertaken. The numerical analysis also looked at internal stress, strain, and concrete cracking. In general, the anchors with the PRs had steady displacement (ductile) and less brittle failure compared to the anchors without the PRs. The significant finding was in the failure mode, where severe concrete damage and concrete breakout failures were prevented by the PRs. The internal tensile stress of concrete was concentrated around the wedges of the anchors (interlocked area). The contribution of the PRs was shown by high strain values at around their mid-length. Additionally, due to the PRs, concrete cracking was less, mostly generated in the region between an anchor and its PRs. The utilization of PRs could be a method to protect concrete from breakout failure.

Micropatterns applied to proton exchange membranes can improve the performance of polymer electrolyte fuel cells; however, the mechanism underlying this improvement is yet to be clarified. In this study, a patterned membrane electrode assembly (MEA) was compared with a flat one using electrochemical impedance spectroscopy and distribution of relaxation time analysis. The micropattern positively affects the oxygen reduction reaction by increasing the reaction area. However, simultaneously, the pattern negatively affects the gas diffusion because it lengthens the average oxygen transport path through the catalyst layer. In addition, the patterned MEA is more vulnerable to flooding, but performs better than the flat MEA in low-humidity conditions. Therefore, the composition, geometry, and operating conditions of the micropatterned MEA should be comprehensively optimized to achieve optimal performance.

Wave observations were carried out at the mouth of Danang Bay and off the Key Ha Cape in central Vietnam from April 1997 to February 1998 in a port development study by the Japan International Cooperation Agency. It is the first long-term measurement of waves in the west South China Sea by reliable wave measurement devices.Wind waves due to typhoons as high as 9m in maximum height were successfully recorded, including those generated by Typhoons 9721 and 9726. Long period waves up to 16 seconds in significant period were revealed to exist. It is proved that the long period waves are swells from a large-scale typhoon remotely located in the west Pacific and propagated through the Luzon Strait to the central coast of Vietnam.Wave hindcast calculations were made by a spectral method for the past 30 typhoons which affected the area from 1961 to 1997. Through statistical treatment of the hindcast waves, it is assessed that an offshore significant wave with a height of 9.7 m could be generated off Danang in a 50-year return period.Seasonal wave climate is that the sea is rather calm, except the typhoon and northeast monsoon season specifically from September to November.

Mammalian embryos undergo major change in their gene expression patterns throughout developmental stages of preimplantation. Following fertilization, the first change is the maternal transcripts to zygotic transition, in which transcripts expressed from the zygotic genome replace maternal transcripts that direct early development of fertilized embryos. The second change of major gene activation, named mid-preimplantation gene activation, precedes the dramatic morphological and functional changes from the morula to blastocyst stage. Currently, genome-wide expression and regulation of genes in preimplantation mouse embryos are explored using several methods, including mRNA differential display and microarray analysis. However, from the aspects of many molecular biological studies, mRNA and protein expressions are not necessarily correlated, as well as little is known regarding the proteome of preimplantation embryos. Here, we studied to obtain detailed information about protein profiles of mouse preimplantation embryos at each developmental stage. Oocytes and zygotes were collected from superovulated ICR female mice by conventional method. In brief, oocytes were collected 48h after PMSG injection, and the following stages collected at all stages (unfertilized egg, 1-cell, 2-cell, 4-cell, 8-cell, morula, and blastocyst stages). All samples were washed with PBS(-) and transferred into 1.5mL tubes and stored at 80°C until protein extracts. The eggs were extracted in lysis buffer containing 7M urea, 2M Thiourea, 4% CHAPS, 0.5% IPG buffer 0.05% TBP, BPB, and protease inhibitors. Isoelectric focusing of the egg extracts was performed using the Immobiline DryStrip of pH 3-10 (GE healthcare). The strip gels were placed on 10% SDS-polyacrylamide gels, stained with SYPRO Ruby (invitrogen). After gel image analysis, gel spots of unfertilized eggs were cut out for MS and MS/MS analysis. The peptide mass fingerprint data generated by the MALDI-TOF/TOF experiments were interpreted using MASCOT. Individual protein profiles during developmental stages were analyzed using TT900 (PerkinElmer). 2D gel electrophoresis of whole egg extract from 600, 10000, and 15000 unfertilized eggs was performed in order to identify as many proteins of the egg proteome as possible. 323 spots excised from the gel of unfertilized eggs were subjected to MALDI-TOF/TOF analysis. 105 spots were identified. The identified proteins were classified into 12 groups. Proteins concerning the protein metabolism and modification were present in the highest numbers. Other proteins were classified into factors such as nucleoside, nucleotide and nucleic acid metabolisms, carbohydrate metabolism, immunity and defense. In addition, we obtained the expression profiles of eggs during developmental stages. In conclusion, this proteome analysis of mouse embryos provides an opportunity to expand our knowledge of the molecular physiology of preimplantation embryos. Detailed comparison of the results from transcriptomics and proteimics are required to understand the molecular mechanism of the embryo development.