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Structures in earthquake-prone areas may suffer from accumulative damages caused by sequential shocks, including the mainshock and aftershock of an earthquake or several strong motions throughout their service lifespan. Sequential shocks lead to a decrease in the capacity of structures. Nevertheless, seismic fragility curves and their applications do not often consider the sequential effect. This study investigates the impact of sequential seismic events on seismic fragility curves of 3-, 6-, and 9-story reinforced concrete buildings constructed before and after 1982 in Japan. The research proposes analytical fragility curves based on dynamic nonlinear multi-degree-of-freedom analyses under the influence of single shock and sequential shock of recorded motions of six destructive earthquakes in Japan. The results demonstrate that the seismic sequence increases the probability of damage ratio. This increase in the fragility curve follows the Gaussian function. The study presents a regression model that can be used for other seismic areas to estimate the effect of seismic sequences on single shock seismic fragility curves. [ABSTRACT FROM AUTHOR]

This paper presents the impact of varying the input seismic excitation directions on the system fragility of a geometrically complex highway bridge structure. The traditional approach of fragility derivation in the principal loading directions (longitudinal and transverse) results in an under/overestimation of the system fragility. To reduce such errors, the contribution of all major vulnerable components to the system fragility in the critical loading direction must be considered. For this purpose, a series of nonlinear time-history analyses were conducted for a testbed configured geometrically curved highway bridge structure in Japan. Shear strain, ductility, and distortion strain were considered as engineering demand parameters for bearings, concrete pier, and steel piers, respectively. The demand dependency among the components was considered using the correlation coefficient matrix for fragility estimation. Subsequently, fragility functions with respect to the input loading directions were generated for the bridge components and system to quantify their sensitivity to seismic input excitation directions. The results show that the component fragility is significantly influenced by the input excitation direction. A relative comparison of the system fragility for different loading directions indicated that a 150° loading direction yielded a higher fragility demand. The findings suggest that the critical fragility assessment should not always be decided only along the principal loading directions. [ABSTRACT FROM AUTHOR]

In the new energy systems' modeling paradigm with high temporal and spatial resolutions, the complexity of renewable resources and demand dynamics is a major obstacle for the scenario analysis of future energy systems and the design of sustainable solutions. Most advanced models are indeed currently restricted by past temporal energy demand data, improper for the analysis of future systems and often insufficient in terms of quantity or spatial resolution. A deeper understanding on energy demand dynamics is thus necessary to improve energy system models and expand their possibilities. The present study introduces noise-assisted multivariate empirical mode decomposition and recurrence quantification analysis for the study of this problematic variable with a case study of Japan's electricity demand data per region. These tools are adapted to nonlinear, complex systems' data and are already applied in a wide range of scientific fields including climate studies. The decomposition of electricity demand as well as the detection of irregularities in its dynamics allow to identify relations with temperature variations, demand sector shares, life style and local culture at different temporal scales. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the top‐down effects of natural enemies on agricultural pests is essential for achieving effective biological control in integrated pest management. However, it is typically difficult to identify causal effects between the interacting species from time‐series data, which have often been monitored for pest forecasting purposes in agricultural ecosystems, as it is likely to involve non‐linear (state‐dependent) population dynamics. In this study, we applied a recently developed framework of non‐linear time‐series analysis (empirical dynamic modelling) to determine top‐down and bottom‐up effects between the citrus whitefly Dialeurodes citri and the whitefly‐specialist ladybird Serangium japonicum. We used weekly monitoring data for the two species collected over 4 years in pesticide‐free citrus groves located in Shizuoka Prefecture, central Japan. Although we were able to identify time‐delayed positive effects of D. citri abundance on S. japonicum abundance, we failed to detect any significant causal effects of S. japonicum abundance on D. citri abundance. Moreover, weather variables (temperature and rainfall) were found to have only a negligible effect on the population dynamics of the two species. Our findings indicate that bottom‐up rather than top‐down effects predominate in the weekly dynamics of this predator–prey system. On the basis of these observations, we discuss whether S. japonicum would be an effective agent for the biological control of D. citri in open‐field systems. [ABSTRACT FROM AUTHOR]

This paper presents comprehensive parametric analyses on the behavior of damage-repaired steel-concrete composite girders using CFRP sheets. Cross-sectional loss was considered on the lower steel flange at midspan to replicate corrosion damage in the girder. Damage was repaired using CFRP sheets to the underside of the lower flange. Non-linear Finite Element (FE) analyses were conducted on the repaired and intact composite girders. The FE models were validated using experimental results and a parametric study was carried out considering the variables such as number of CFRP sheets, CFRP elastic modulus, damage amount, epoxy resin elastic modulus, concrete strength, flange strength, and CFRP bonding area. The effect of parameters on failure components was studied for Limit States 1, 2, and 3 defined in the revised Design Specification for Highway Bridges in Japan (JSHB) (2017). Limit States 1 and 3 correspond to the service limit and ultimate Limit States in AASHTO, respectively. However, Limit State 2 is JSHB unique Limit State located between 1 and 3 in terms of functionality. Regression models were proposed to determine the load-carrying capacity of the repaired composite girder for 3 Limit States. Comparison between the proposed equation and FE-predicted values showed good agreement with prediction errors of ±10% to ±19%. The study showed that to restore the stiffness and load capacities for Limit State 1 high-modulus CFRP sheets and resins are more suitable options than the low-modulus sheets and resins. Finally, the study proposes the optimal repair method for damaged composite girder considering the Limit States. • Parametric analyses of damage repaired steel-concrete composite girder were conducted using CFRP sheets. • Effect of various parameters has been investigated. • Equations for loadcapacities of repaired composite girders for Limit States 1, 2 and 3 have been proposed. [ABSTRACT FROM AUTHOR]

Since the financial system has illustrated an increasingly prominent characteristic of inextricable connections, information theory is gradually utilized to study the financial system. By collecting the daily data of industry index (2005-2020) and region index (2012-2020) listed in China as samples, this paper applies an innovative measure named partial mutual information on mixed embedding to generate directed networks. Based on the analysis of nonlinear relationships among sectors, this paper realizes the accurate construction of "time-varying" financial network from the perspective of risk spillover. The results are presented as follow: (1) interactions can be better understood through the nonlinear networks among distinct sectors, and sectors in the networks could be classified into different types according to their topological properties connected to risk spillover; (2) in the rising stage, information is transmitted rapidly in the network, so the risk is fast diffused and absorbed; (3) in the declining stage, the network topology is more complex and panic sentiments have long term impact leading to more connections; (4) The US market, Japan market and Hongkong market have significant affect on China's market. The results suggest that this nonlinear measure is an effective approach to develop financial networks and explore the mechanism of risk spillover. [ABSTRACT FROM AUTHOR]

Purpose: To develop a pharmacokinetic (PK) and pharmacodynamic (PD) model for neutropenia following nab-paclitaxel administration and identify factors associated with drug disposition and changes in neutrophil counts in patients with solid cancer.Methods: PK/PD analysis by nonlinear mixed effects approach was performed using the data from 27 patients who participated in phase I studies of nab-paclitaxel monotherapy conducted in Japan. The patients were treated with either weekly (80, 100, or 125 mg/m2) or every 3 weeks (200, 260, or 300 mg/m2). The observed paclitaxel concentrations in whole blood and neutrophil counts in the first cycle were used for PK/PD analysis. Covariate analysis was performed to identify factors affecting PK and the decrease in neutrophil counts.Results: The developed 3-compartment, non-linear PK model described relationships of body surface area with total body clearance and volume of distribution for the peripheral compartment. Covariate factors affecting neutrophil counts were age and serum albumin level. Simulation based on the developed PK/PD model showed a substantial impact of age and serum albumin level on the time course of neutrophil counts after nab-paclitaxel administration. Advanced age was related to greater decrease in neutrophil counts, and serum albumin level, inversely related to change in neutrophil counts.Conclusion: We have developed a novel PK/PD model for nab-paclitaxel in which age and serum albumin level were considered clinically important covariate factors. This model needs to be further validated using a larger patient population. [ABSTRACT FROM AUTHOR]

Azilsartan (AZL), the active metabolite of azilsartan medoxomil, is the newest angiotensin receptor blocker that has been approved for the treatment of hypertension in 2012 in Japan. The present study aimed to evaluate the safety and pharmacokinetic properties of AZL in healthy Chinese subjects. We performed 2 phase 1 studies to investigate the pharmacokinetics and safety of AZL in healthy Chinese adults after a single dose (20 mg or 40 mg) or multiple doses of AZL (40 mg/d for 7 days; Study I) and after a single 40‐mg dose under the fasted and fed conditions (Study II). Noncompartmental analysis and nonlinear mixed‐effects modeling were used to analyze the pharmacokinetic properties of AZL. Twenty‐seven healthy volunteers (14 men and 13 women) aged 20‐32 years were enrolled and completed the study. During single dosing of AZL, the pharmacokinetics of AZL exhibited a linear profile between dosage and area under the concentration‐time curve. There is no AZL accumulation after multiple doses. Food had no effect on the pharmacokinetic characteristics of AZL. AZL concentrations were best fit with a 2‐compartment model, and the typical value of clearance was 1.63 L/h. Body weight had an impact on both the apparent clearance and peripheral volume of distribution. The pharmacokinetic parameters were consistent with previous studies in non‐Chinese subjects. Model‐based simulations indicated that a 45‐kg subject would have approximately double the AZL exposure of a 90‐kg subject. Whether the exposure difference has clinical significance needs to be confirmed in further studies among patients. [ABSTRACT FROM AUTHOR]

Tsunami evacuation simulations are often used to determine necessary countermeasures that will reduce human loss effectively after earthquakes and subsequent tsunamis. However, so far there has been no simulation for the estimated building damage using up-to-date knowledge of seismic engineering. In this study, in order to clarify the effect of building damage on a tsunami evacuation, we first predicted building damage based on the nonlinear response analysis for a realistic strong ground motion and then simulated a tsunami evacuation considering road blockage due to the collapsed buildings. We used one district in Tanabe City in Wakayama Prefecture in Japan where we expect to have a 12 m of tsunami height after an earthquake along the Nankai Trough plate boundary. We found that the prepared capacity of evacuation sites is not enough to let everyone evacuate and that the number of survivors increases by 3–4% if all of the buildings and houses are seismically reinforced. Considering this, plus 1% of expected casualties inside the collapsed houses, it appears to be not as efficient to reinforce buildings and houses to prevent human loss in comparison with increasing the capacity of tsunami evacuation sites in the target district. However, the damage to building and houses will cause a lot of side effects which are not considered here, but will prolong the evacuation time. Thus, we concluded that we need to reinforce the buildings and houses as well as consider the appropriate placement, number, and capacity of the evacuation sites. [ABSTRACT FROM AUTHOR]

Introduction: The authors previously reported a CT-based nonlinear finite element analysis (nonlinear CT/FEA) model to investigate loading stress distribution in the femoral shaft of patients with atypical femoral fractures (AFFs). This showed that stress distribution, influenced primarily by femoral bowing, may determine the location of AFF. Here, we demonstrate the locational characteristics associated with AFFs in an Asian, specifically Japanese, population regarding bone strength. This is the second report from our multicentre research project suggesting a possible new concept of diagnostic criteria or treatment according to AFF subtype.Patients and Methods: A multicentre prospective study was conducted at 12 hospitals in Japan from August 2015 through June 2018. We recruited three study groups composed of elderly females over the age of 60 years-the mid-shaft AFF group (n = 14; 80.0 ± 6.5 years), the subtrochanteric AFF group (n = 15; 73.9 ± 6.8 years), and the control group who had sustained unilateral hip fracture (n = 21; 82.1 ± 7.1 years)-and analysed femoral neck bone density and strength. Bone strength of the femoral neck was predicted with an evaluation method using nonlinear CT/FEA in both standing and falling configuration.Results: Femoral neck bone density and strength were significantly higher in the subtrochanteric AFF group compared with the mid-shaft AFF and control groups (p <  0.0001). No significant difference was seen in bone strength between the mid-shaft AFF and control groups (standing, p =  0.7616; falling, p =  0.3803).Conclusions: AFF has different features, in terms of bone strength, depending on fracture location. At the very least, Japanese patients with mid-shaft AFF could be at high risk of hip fracture because of bone fragility, in contrast to the firm bone of subtrochanteric AFF. For internal fixation of mid-shaft AFF using an IM nail, cervical screw insertion toward the femoral head might be recommended to prevent possible hip fracture. [ABSTRACT FROM AUTHOR]

The relationship between money growth and inflation is a topic of debate among macroeconomists. This paper contributes to the empirical literature on the money‐inflation pass‐through using a Nonlinear Auto‐Regressive Distributed Lag model (NARDL) for three countries (the U.S., U.K. and Japan) over an estimation period spanning 1950Q1 to 2014Q4. This methodology allows for empirical tests of short‐ and long‐run asymmetric responses of inflation to both positive and negative shocks affecting money growth of three monetary aggregates (M1, M2, M0). The results reveal that inflation responds asymmetrically to monetary shocks in the long‐run for all three countries. Robustness tests are also undertaken by carrying out the Hatemi‐J (Empirical Economics, Vol. 43 (2012), pp. 447–456) causality test and splitting the sample period into two, before and after the financial crisis. The findings indicate the existence of a relation between money growth and inflation in the post‐crisis period only in the case of the U.K. When we use different break points, we find that the symmetric relationship more likely occurs in the post‐crisis period. [ABSTRACT FROM AUTHOR]

This study theoretically clarifies the non-linear transition mechanism of production and Japanese economic development. This mechanism is empirically known but the precise nature of the shifts is unclear and has yet to be specified theoretically. The study focuses on four factors: economies of scale, the operating rate, the vintage facilities, and the international transfer of facilities, all of which would impact on the transition mechanism and from which a new model is derived. This model demonstrates the jumping processes involved in production highlighting the existences of thresholds, which induce them. These thresholds relate to the identified factors and which provide an explanation for rapid increases and sudden declines in production. This study investigates specific cases of such changes in the Japanese manufacturing sector and reviews the role of these four factors. Illustrated is the non-linear nature of the transition mechanism in its effect on the Japanese economic growth. [ABSTRACT FROM AUTHOR]

Abstract: A full-scale four-story welded steel moment-frame building was shaken to collapse on the E-Defense shaking table in Japan in September 2007. This building was used as a case study to investigate modeling techniques for nonlinear structural and collapse simulations. This paper presents various kinds of numerical models for beams, columns, and panel zones. The analytical studies suggest that the fiber-beam frame model considering composite beam effects simulates the responses of the four-story building specimen better than the hinge-beam frame model. Considering panel zone deformations in the numerical model can improve the accuracy of computing the displacement-related responses. Moreover, considering the effects of the composite beam action on the panel zone stiffness and strength can further enhance the accuracy of the response simulations. The column model incorporating fiber-beam–column element using cyclic buckling fibers proposed in this study can satisfactorily simulate the degrading force versus deformation relationships of the three-dimensional shell column model due to the local buckling. A frame model incorporating the same type of fibered column element could predict the collapse time of the test building. Based on these nonlinear response analyses, it is illustrated that the responses of the building can be estimated satisfactorily by using the modeling techniques presented in this study. [Copyright &y& Elsevier]

• A novel controlled-rocking concentrically braced frame (CR-CBF) system is developed. • Seismic performance of the (CR-CBF) system is evaluated by using incremental dynamic procedure (IDA). • The developed CR-CBF shows an efficient safety margin against collapse under different hazard intensities. • The new CR-CBF can be used as an alternative earthquake resisting system. Recent earthquakes in New Zealand and Japan showed that structures designed according to modern building codes might suffer significant damages with hefty financial and social losses. The primary reason lies in the seismic design approach, where most seismic force resisting systems (SFRS) were designed to prevent structures from collapse during strong earthquake shaking, without considering the damage and the usability of the structure after an earthquake. In this paper, a controlled rocking-concentrically braced frame (CR-CBF) is proposed. CR-CBF is a fused structural system that uses a combination of post-tensioned tendons (PTs) and energy dissipation devices (EDs) to create a controlled-rocking mechanism to minimize structural repair costs and down time after a strong earthquake. PTs are placed in the structure to provide the restoring forces and to minimize any residual deformation in the structure, while EDs are placed at the base of a structure to dissipate the earthquake energy. To ensure the CR-CBF can achieve high performance, two (CR-CBF) prototypes with different heights are designed using the novel equivalent energy design procedure (EEDP). The EEDP procedure allows designers to select different performance objectives at different shaking intensities. The results of nonlinear dynamic analyses of the CR-CBFs show that CR-CBFs have superior seismic performances as intended and can be efficiently designed using EEDP. Finally, the seismic performance of CR-CBF against collapse is assessed using incremental dynamic analysis (IDA) outlined in the FEMA-P695 methodology. The results show that the CR-CBFs designed by EEDP have sufficient safety against collapse, hence it can be used as an efficient seismic force resisting system. [ABSTRACT FROM AUTHOR]