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The purpose of this study is to design a spherical sensor which can detect the surge from various directions to lay the foundation of the research of surge.

This paper designed a spherical sensor to detect the impact force generated by the surge. To realize the depth and stability control of the shallow underwater vehicles, it is necessary to do research and analysis on the surge in shallow waters. The spherical sensor with novel structure was skillfully composed of 24 cantilever beam pressure-type strain sensors. It is powerful to detect the surge from various directions simultaneously.

It is proved that the spherical sensor can accurately collect the surge data from multiple directions through experiments, which laid the foundation of the anti-surge study.

Surge is not a new topic. But there is no effective tool to detect surge. The research of this paper is an attempt to provide an available tool to analyze surge. The research limitation is that the pool where the spherical sensor is installed is a little small. In the future, a bigger pool can be used.

A deep and comprehensive analysis of surge can be conducted according to the surge data detected by the spherical sensor to achieve the essential features of surge. This lays the foundation for the accurate control of Autonomous Underwater Vehicles (AUVs), especially fixed depth and stability control.

As the control accuracy of AUVs increases, the AUVs can perform much more difficult tasks such as port monitoring, underwater salvaging, underwater pipeline maintenance and so on. These can be applied in commercial applications or in the national defense of many countries.

A novel spherical sensor using 24 cantilever beam pressure-type strain sensors to detect the surge was designed. The spherical sensor was installed in the physical surge simulator to collect surge data and conduct an analysis of the collected data.

The purpose of this paper is to consider the transition of surge episodes to stop episodes and differentiates between two types of surges, namely, surges that end in stops and surges that end in normal episodes.

Previous studies show that surges end in output contractions, crises, and reversals of capital inflows. However, when one looks closely at the data, more than half of surges end in normal episodes at least four quarters following the last surge quarter.

The results show the varying significance of global and domestic factors correlated with the occurrence of surges leading to stops and the size of gross inflows during these two types of surges.

The findings highlight the importance of differentiating between these two types of surges as it leaves scope for policy design in safeguarding financial stability amidst surging capital inflows.

Leakage current is one of the factors, which can contribute towards degradation of surge arresters. Thus, the purpose of this paper is to study on leakage current within surge arresters and improvement on their design.

In this work, a three-dimensional model geometry of 11 kV zinc oxide surge arrester was designed in finite element analysis and was applied to calculate the leakage current under normal operating condition and being verified with measurement results. The optimisation methods were used to improve the arrester design by minimising the leakage current across the arrester using imperialist competitive algorithm (ICA) and gravitational search algorithm (GSA).

The arrester design in reducing leakage current was successfully optimised by varying the glass permittivity, silicone rubber permittivity and the width of the ground terminal of the surge arrester. It was found that the surge arrester design obtained using ICA has lower leakage current than GSA and the original design of the surge arrester.

The comparison between measurement and simulation enables factors that affect the mechanism of leakage current in surge arresters to be identified and provides the ideal design of arrester.

Surge arrester design was optimised by ICA and GSA, which has never been applied in past works in designing surge arrester with minimum leakage current.

Planning inventories for emergency supplies such as bottled water, non‐perishable foods, batteries, and flashlights can be challenging for retailers situated within the projected path of a severe storm. The retailer's inventory decisions are complicated by the inherent volatility of storm forecasts and the corresponding demand predictions. The purpose of this paper is to explore both proactive and reactive inventory control policies within the context of probable pre‐storm demand surge for a fast‐moving emergency supply item, and identify the conditions that are most conducive to each strategy according to the minimax decision criterion.

The inventory system is formulated based on an underlying economic order quantity framework. Minimax decision rules are developed analytically. Sensitivity analysis is facilitated by both analytic and numerical methods.

The conditions that are conducive to a proactive ordering strategy are limited supplier flexibility, acute demand surge, and exorbitant reorder costs; otherwise, the minimax inventory control policy is given by a reactive ordering strategy.

The above‐mentioned findings are based on a stylized inventory model characterized by assumptions that are consistent with the academic literature. In order to assess the implications of these results in practice, the model should be extended according to the relevance of each assumption to specific real‐world inventory systems.

Householders preparing for probable evacuation or post‐storm power outages typically overwhelm grocery and home improvement stores during a brief period prior to the impact of an approaching weather system. This phenomenon triggers a temporary spike in demand for several stock keeping units, which is oftentimes accompanied by pervasive inventory shortages that proliferate community vulnerability and engender a sense of disarray throughout the local populace. Effective inventory management of emergency supply items during this period can help alleviate some of these social dilemmas.

Few academic publications address inventory management from the perspective of humanitarian relief. Among existing studies, the emphasis has been coordination of emergency supplies for post‐disaster relief and recovery activities. This paper appears to be the first academic investigation of an inventory system driven by the pre‐storm demand surge for emergency supplies that typically occurs in the presence of an ominous and potentially devastating weather system. Additionally, this study conceivably represents the first minimax distribution free approach to inventory control within the context of humanitarian logistics and disruption management.

The purpose of this paper is to examine whether surge in foreign direct investment (FDI) inflows leads to surge in economic growth in 52 developing countries for the period 1990-2014.

The author used a threshold approach to identify surge incidences in gross domestic product (GDP) per capita growth rates and FDI inflows (measured as percentage of GDP) for each country included in the sample. Three different criteria are used to identify surge instances. As a preliminary analysis the author used the probit and complementary log–log regression methods to estimate the likelihood of growth surge occurrence. To correct the potential endogeneity problem the author jointly estimated the growth surge and FDI surge equations using the recursive bivariate probit (RBP) regression.

The author found that East Asia and the Pacific region has highest rate of growth surge incidences followed by South Asia. The results suggest that surge in FDI inflows significantly increases the likelihood of growth surge. The finding is robust to alternative surge definitions and methods of estimation.

The analysis reveals that inbound FDI flow is a critical driver of economic growth in developing countries. Large FDI inflows matters for achieving rapid economic growth. Therefore developing countries should adopt favourable policies to attract more FDI. Policymakers should focus on improving the investment climate of the country to boost domestic investment and to attract larger amount of FDI into the economy.

To the best of the author’s knowledge this is the first study to examine whether surge in FDI inflows stimulates surge in economic growth in developing countries. The analysis reveals that FDI surge is a robust predictor of rapid economic growth in developing countries.

The paper aims to present an outline of the technology of the active anti-surge algorithm based on high-frequency pressure measurement. The presented system is fast, inexpensive and reliable and does not limit the machine-operating range. Many contemporary anti-surge systems are based on theoretical surge margin. This solution limits machine operating range by about 10-15 per cent in the region of the highest pressure ratios. It is also often sensitive to change in external conditions such as temperature or density, as the system reacts to limits calculated theoretically.

This paper presents results of pressure measurements obtained on the low-speed centrifugal blower DP1.12. The pressure signals were presented in the form of phase diagrams, and conclusions were drawn from their phase portraits to develop the surge indication parameter.

The presented safety system uses the signal to develop the so-called (rate of derivative fluctuation) RDF parameter. In nominal working conditions, this parameter keeps the value close to 1. When RDF reaches values over 3, the anti-surge procedure should be implemented. Experimental studies have shown that this algorithm assures enough time to incur actions suppressing unstable phenomena.

The system reacts to real machine working conditions and is hence reliable. The RDF algorithm could also be used to identify local flow instabilities, as well as off-design operation.

This paper aims to investigate the relationship between capital flow surges, reversals and sudden stops.

Emphasizing the importance of looking at the behavior of domestic as well as foreign capital flows, the authors distinguish sudden stops from capital flow reversals by attributing the former to foreign capital flows only.

It is found that, despite the large differences in the number of surges identified by several different measures in the literature, a majority of surges do end in reversals of some type. The percentages tend to be slightly over half for surges in net capital flows, but on average, 70 per cent of gross surges end in sudden stops. Furthermore, contrary to popular belief, approximately half of sudden stops and net capital flow reversals are not preceded by surges. It is also found that surges that persist longer are more likely to turn into sudden stops and reversals.

The authors find substantial empirical differences in the characteristics of sudden stops (based on gross foreign flows) and reversals (based on net flows).

Large inflows of financial capital are not always a strong indicator that a country’s economic policies will continue to provide stability in the future. They may signal an increase rather than reduction in the risk of future instability.

This study focuses on an issue that has been less explored to date, the relationship between capital flow surges, reversals and sudden stops. The authors distinguish, redefine and document differences among capital flow reversals and sudden stops. Duration of surges is related to the likelihood of having reversals and sudden stops.

The growth in digital telecom systems around the world has led to an increase in demand for surge protection components. These components often use low ohm resistor compositions in a serpentine configuration. The demands placed upon these materials during pulsing are high. Not only are the materials expected to withstand more severe pulses, they are also expected to have minimal adverse effect on the environment. To meet these increased demands, a new system of surge resistor materials has been developed. The design, manufacture and testing of these materials ensures optimum performance in high voltage surge applications. This paper describes the performance of this new surge resistor system and discusses how the performance of the resistors relates to the paste constituents, encapsulant materials and the laser trimming process.

Health systems are periodically confronted by crises – think of Severe Acute Respiratory Syndrome, H1N1, and Ebola – during which they are called upon to manage exceptional situations without interrupting essential services to the population. The ability to accomplish this dual mandate is at the heart of resilience strategies, which in healthcare systems involve developing surge capacity to manage a sudden influx of patients. The paper aims to discuss these issues.

This paper relates insights from resilience research to the four “S” of surge capacity (staff, stuff, structures and systems) and proposes a framework based on complexity theory to better understand and assess resilience factors that enable the development of surge capacity in complex health systems.

Detailed and dynamic complexities manifest in different challenges during a crisis. Resilience factors are classified according to these types of complexity and along their temporal dimensions: proactive factors that improve preparedness to confront both usual and exceptional requirements, and passive factors that enable response to unexpected demands as they arise during a crisis. The framework is completed by further categorizing resilience factors according to their stabilizing or destabilizing impact, drawing on feedback processes described in complexity theory. Favorable order resilience factors create consistency and act as stabilizing forces in systems, while favorable disorder factors such as diversity and complementarity act as destabilizing forces.

The framework suggests a balanced and innovative process to integrate these factors in a pragmatic approach built around the fours “S” of surge capacity to increase health system resilience.

The paper explores and characterizes antifragility in simple inventory systems exposed to demand variability, providing the initial inroads to operationalizing antifragility in the context of inventory management. Antifragility refers to the feature of a system that can benefit from uncertainty, rather than suffer from it. The paper expands the concept of inventory beyond that of risk mitigation and towards one of enabling antifragility.

The study employs analytical and simulation modelling of an inventory system with two classes of demand. To separate the influence of factors, a simple inventory policy with a range of fixed order quantities is modelled, allowing for the identification of antifragile regions in an experimental space.

Outputs uncover a variety of performance outcomes, ranging from settings where additional inventory yields no benefit, to areas where additional inventory results in increasing normalized profit with increasing uncertainty, demonstrating antifragility. In between these regions, increases in normalized profit are bounded, and confined to specific regions.

This research expands academic understanding of inventory as a vehicle to achieving antifragile outcomes. Although this paper does not solve for an optimal policy as typical inventory research does, it instead characterizes the antifragile outcomes within simple inventory systems. Further research should be carried out to investigate antifragility in settings of greater complexity and design ordering policies leveraging inventory towards a gain from uncertainty.

Typically, inventory is used to buffer against uncertainty, and, with a given amount of inventory, the performance is expected to degrade with increasing variability. In this paper, the authors demonstrate that certain levels of additional inventory can result in antifragility and increase profitability as uncertainty increases, extending beyond traditional conceptualizations of inventory and uncertainty.

Empirical research into designing antifragile outcomes is limited, with very few examples of increasing performance with increases in uncertainty. This article presents an initial empirical exploration of how additional inventory can result in antifragility.