Fundamental Study on Deterioration Estimation Method of Fire-Damaged Concrete by the Impact Elastic Wave Method.

The majority of the water distribution pipes which take the greater part of Japanese drinking water utilities' assets are made of iron such as gray/ductile cast iron or steel. It will be necessary to replace most of these pipes due to corrosion in the near future. In general, pipeline assessment which is done before replacement is carried out through digging to take visual observation; however, digging costs and environmental burden due to digging will become a problem. This study therefore undertakes a research into methods of pipeline assessment which reduce the digging necessity. In the study of the Impact Elastic-Wave Method, elastic-waves were applied to cast iron pipes whose external surfaces were in various states of corrosion (pitting, partial, uniform, etc.); the frequency component of the received waves showed that there was a tendency for the frequency component of the waves for corroded iron pipes to be distributed in a lower range than sound pipes. In addition, it also showed that it is possible to discriminate the thickness reduction of approximately one mm. These results demonstrate the possibility of applying this method to pipeline assessment without or with minimum digging.

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Institutional Quality and Trade Flow: Empirical Evidence from Malaysia and Other OIC Member Countries in Africa

Insight on Africa ◽

10.1177/0975087820987174 ◽

2021 ◽

pp. 097508782098717

Author(s):

Hammed Agboola Yusuf ◽

Luqman Olanrewaju Afolabi ◽

Waliu Olawale Shittu ◽

Kafilah Lola Gold ◽

Murtala Muhammad

Keyword(s):

Economic Growth ◽

Bilateral Trade ◽

Trade Flow ◽

Estimation Method ◽

Institutional Quality ◽

Likelihood Estimation ◽

Political Stability ◽

Bilateral Trade Flow ◽

World Governance Indicators ◽

The Impact

This article examines the impact of institutional quality on bilateral trade flow between Malaysia and selected 25 African Organisation of Islamic Cooperation (OIC) member countries. Four institutional qualities were selected from World Governance Indicators with other trade predictors from the period from 1985 to 2016. Using gravity model of trade and Poisson pseudo-maximum likelihood estimation method (PPML) technique, the results confirm that government effectiveness, regulatory quality and political stability have an adverse effect on bilateral trade flow among the OIC countries in Africa. On the other hand, these institutional quality variables were considered as a strength for Malaysian economic growth. Therefore, better institutional quality reforms are needed among OIC member countries in Africa in order to accelerate trade, economic growth and development in their region.

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A Fundamental Study on the Development of New Energy Performance Index in Office Buildings

Energies ◽

10.3390/en14082064 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2064

Author(s):

Jin-Hee Kim ◽

Seong-Koo Son ◽

Gyeong-Seok Choi ◽

Young-Tag Kim ◽

Sung-Bum Kim ◽

...

Keyword(s):

Energy Consumption ◽

Energy Requirement ◽

Energy Performance ◽

Office Buildings ◽

Light Transmittance ◽

Wall Structure ◽

Fundamental Study ◽

Future Studies ◽

U Value ◽

The Impact

Recently, there have been significant concerns regarding excessive energy use in office buildings with a large window-to-wall ratio (WWR) because of the curtain wall structure. However, prior research has confirmed that the impact of the window area on energy consumption varies depending on building size. A newly proposed window-to-floor ratio (WFR) correlates better with energy consumption in the building. In this paper, we derived the correlation by analyzing a simulation using EnergyPlus, and the results are as follows. In the case of small buildings, the results of this study showed that the WWR and energy requirement increase proportionally, and the smaller the size is, the higher the energy sensitivity will be. However, results also confirmed that this correlation was not established for buildings approximately 3600 m2 or larger. Nevertheless, from analyzing the correlation between the WFR and the energy requirements, it could be deduced that energy required increased proportionally when the WFR was 0.1 or higher. On the other hand, the correlation between WWR, U-value, solar heat gain coefficient (SHGC), and material property values of windows had little effect on energy when the WWR was 20%, and the highest effect was seen at a WWR of 100%. Further, with an SHGC below 0.3, the energy requirement decreased with an increasing WWR, regardless of U-value. In addition, we confirmed the need for in-depth research on the impact of the windows’ U-value, SHGC, and WWR, and this will be verified through future studies. In future studies on window performance, U-value, SHGC, visible light transmittance (VLT), wall U-value as sensitivity variables, and correlation between WFR and building size will be examined.

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Reliability Assessment of a Multi-State HVDC System by Combining Markov and Matrix-Based Methods

Energies ◽

10.3390/en14113097 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3097

Author(s):

Roberto Benato ◽

Antonio Chiarelli ◽

Sebastian Dambone Sessa

Keyword(s):

Current System ◽

Estimation Method ◽

Reliability Estimation ◽

Voltage Source ◽

Voltage Source Converter ◽

Hvdc System ◽

Critical Elements ◽

The Matrix ◽

The Impact

The purpose of this paper is to highlight that, in order to assess the availability of different HVDC cable transmission systems, a more detailed characterization of the cable management significantly affects the availability estimation since the cable represents one of the most critical elements of such systems. The analyzed case study consists of a multi-terminal direct current system based on both line commutated converter and voltage source converter technologies in different configurations, whose availability is computed for different transmitted power capacities. For these analyses, the matrix-based reliability estimation method is exploited together with the Monte Carlo approach and the Markov state space one. This paper shows how reliability analysis requires a deep knowledge of the real installation conditions. The impact of these conditions on the reliability evaluation and the involved benefits are also presented.

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The impact of globalization on the performance of Banks in South Africa

Review of International Business and Strategy ◽

10.1108/ribs-02-2016-0003 ◽

2016 ◽

Vol 26 (4) ◽

pp. 517-542 ◽

Cited By ~ 3

Author(s):

Fadzlan Sufian ◽

Fakarudin Kamarudin

Keyword(s):

South Africa ◽

Host Country ◽

Banking Sector ◽

Generalized Method Of Moments ◽

Estimation Method ◽

Bank Performance ◽

Content Type ◽

Multinational Banks ◽

Dynamic Panel Regression ◽

The Impact

Purpose This paper aims to provide empirical evidence for the impact globalization has had on the performance of the banking sector in South Africa. In addition, this study also investigates bank-specific characteristics and macroeconomic conditions that may influence the performance of the banking sector. Design/methodology/approach The authors use data collected for all commercial banks in South Africa between 1998 and 2012. The ratio of return on assets was used to measure bank performance. They then used the dynamic panel regression with the generalized method of moments as an estimation method to investigate the potential determinants and the impact of globalization on bank performance. Findings Positive impact of greater economic integration and trade movements of the host country, while greater social globalization in the host country tends to exert negative influence on bank profitability. The results show that banks originating from the relatively more economically globalized countries tend to perform better, while banks headquartered in countries with greater social and political globalizations tend to exhibit lower profitability levels. Originality/value An empirical model was developed that allows for the performance of multinational banks to depend on internal and external factors. Moreover, unlike the previous studies on bank performance, in this empirical analysis, we control for the different dimensions of globalizations while taking into account the origins of the multinational banks. The procedure allows us to test for the home field, the liability of foreignness and global advantage hypotheses to deduce further insights into the prospects of banking across borders.

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A Modified Extended Kalman Filter for a Two-Antenna GPS/INS Vehicular Navigation System

Sensors ◽

10.3390/s18113809 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3809 ◽

Cited By ~ 6

Author(s):

Yushi Hao ◽

Aigong Xu ◽

Xin Sui ◽

Yulei Wang

Keyword(s):

Kalman Filter ◽

Extended Kalman Filter ◽

Navigation System ◽

Adaptive Estimation ◽

Estimation Method ◽

Measurement Noise ◽

Model Errors ◽

State Process ◽

Stability And Accuracy ◽

The Impact

Recently, the integration of an inertial navigation system (INS) and the Global Positioning System (GPS) with a two-antenna GPS receiver has been suggested to improve the stability and accuracy in harsh environments. As is well known, the statistics of state process noise and measurement noise are critical factors to avoid numerical problems and obtain stable and accurate estimates. In this paper, a modified extended Kalman filter (EKF) is proposed by properly adapting the statistics of state process and observation noises through the innovation-based adaptive estimation (IAE) method. The impact of innovation perturbation produced by measurement outliers is found to account for positive feedback and numerical issues. Measurement noise covariance is updated based on a remodification algorithm according to measurement reliability specifications. An experimental field test was performed to demonstrate the robustness of the proposed state estimation method against dynamic model errors and measurement outliers.

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