Search results for: internal erosion
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2922

Search results for: internal erosion

2322 Evaluating Viability of Solar Tubewell Irrigation Technology

Authors: Junaid N. Chauhdary, Bernard A. Engel, Allah Bakhsh

Abstract:

Solar powered tubewells can be a reliable and affordable source of supplying irrigation water compared with electric or diesel operated tubewells due to frequent load shedding and soaring energy prices. A study was conducted on a solar tubewell installed at the Water Management Research Center (WMRC), University of Agriculture, Faisalabad to investigate the viability of a solar powered tubewell in terms of discharge and benefit cost ratio. The tubewell discharge was 50 m3hr-1 with a total dynamic head of 30 m. The depth of bore was 31 m (14 m blind + 17 m screen) with a casing diameter of 15.2 cm (6 inches). A 3-stage submersible pump of 10.2 cm (4 inch) diameter was lowered in the casing to a depth of 22 m. The pump was powered from 21 solar panels of 200 W capacity each. The tubewell peak discharge was observed as 6 and 7 hr day-1 in winter and summer, respectively. The breakeven analysis of the solar tubewell showed that the payback period of the solar tubewell was 1.5 years of its 10 year usable life with an IRR (internal rate of return) of 69 %. The BCR (benefit cost ratio) of the solar tubewell at 2, 4, 6, and 8 percent discount rate were 3.75, 3.45, 3.19 and 2.96, respectively. The NPV (net present value) of the solar tubewell at 2, 4, 6, and 8 % discount rates were 1.89, 1.65, 1.45 and 1.27 million rupees, respectively. These results indicated that the solar powered tubewells are a viable option as well as environmentally friendly and can be adopted by the farmers due to their affordable payback period.

Keywords: benefit cost ratio, internal rate of return (IRR), net present value (NPV), solar tubewell

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2321 Using Scanning Electron Microscope and Computed Tomography for Concrete Diagnostics of Airfield Pavements

Authors: M. Linek

Abstract:

This article presents the comparison of selected evaluation methods regarding microstructure modification of hardened cement concrete intended for airfield pavements. Basic test results were presented for two pavement quality concrete lots. Analysis included standard concrete used for airfield pavements and modern material solutions based on concrete composite modification. In case of basic grain size distribution of concrete cement CEM I 42,5HSR NA, fine aggregate and coarse aggregate fractions in the form of granite chippings, water and admixtures were considered. In case of grain size distribution of modified concrete, the use of modern modifier as substitute of fine aggregate was suggested. Modification influence on internal concrete structure parameters using scanning electron microscope was defined. Obtained images were compared to the results obtained using computed tomography. Opportunity to use this type of equipment for internal concrete structure diagnostics and an attempt of its parameters evaluation was presented. Obtained test results enabled to reach a conclusion that both methods can be applied for pavement quality concrete diagnostics, with particular purpose of airfield pavements.

Keywords: scanning electron microscope, computed tomography, cement concrete, airfield pavements

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2320 Impact of Financial Factors on Total Factor Productivity: Evidence from Indian Manufacturing Sector

Authors: Lopamudra D. Satpathy, Bani Chatterjee, Jitendra Mahakud

Abstract:

The rapid economic growth in terms of output and investment necessitates a substantial growth of Total Factor Productivity (TFP) of firms which is an indicator of an economy’s technological change. The strong empirical relationship between financial sector development and economic growth clearly indicates that firms financing decisions do affect their levels of output via their investment decisions. Hence it establishes a linkage between the financial factors and productivity growth of the firms. To achieve the smooth and continuous economic growth over time, it is imperative to understand the financial channel that serves as one of the vital channels. The theoretical or logical argument behind this linkage is that when the internal financial capital is not sufficient enough for the investment, the firms always rely upon the external sources of finance. But due to the frictions and existence of information asymmetric behavior, it is always costlier for the firms to raise the external capital from the market, which in turn affect their investment sentiment and productivity. This kind of financial position of the firms puts heavy pressure on their productive activities. Keeping in view this theoretical background, the present study has tried to analyze the role of both external and internal financial factors (leverage, cash flow and liquidity) on the determination of total factor productivity of the firms of manufacturing industry and its sub-industries, maintaining a set of firm specific variables as control variables (size, age and disembodied technological intensity). An estimate of total factor productivity of the Indian manufacturing industry and sub-industries is computed using a semi-parametric approach, i.e., Levinsohn- Petrin method. It establishes the relationship between financial factors and productivity growth of 652 firms using a dynamic panel GMM method covering the time period between 1997-98 and 2012-13. From the econometric analyses, it has been found that the internal cash flow has a positive and significant impact on the productivity of overall manufacturing sector. The other financial factors like leverage and liquidity also play the significant role in the determination of total factor productivity of the Indian manufacturing sector. The significant role of internal cash flow on determination of firm-level productivity suggests that access to external finance is not available to Indian companies easily. Further, the negative impact of leverage on productivity could be due to the less developed bond market in India. These findings have certain implications for the policy makers to take various policy reforms to develop the external bond market and easily workout through which the financially constrained companies will be able to raise the financial capital in a cost-effective manner and would be able to influence their investments in the highly productive activities, which would help for the acceleration of economic growth.

Keywords: dynamic panel, financial factors, manufacturing sector, total factor productivity

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2319 Assessment of the Economic Factors and Motivations towards De-Dollarization since the Early 2000s and Their Implications

Authors: Laila Algalal, Chen Xi

Abstract:

The US dollar has long served as the world's primary reserve currency. However, this dominance faces growing challenges from internal US economic pressures and the rise of alternative currencies. Internally, issues like high debt, inflation, reduced competitiveness, and economic instability due to inequality in economic policies threaten the dollar's position. Externally, more countries are establishing alternative currencies, payment systems, and regional financial institutions to reduce dollar dependence. These drivers have contributed to a decline in the dollar's share of global foreign exchange reserves from 71% in 2001 to an estimated 58% in 2022. While this 13-percentage point drop took two decades, recent initiatives suggest de-dollarization could accelerate in the coming few decades. Efforts to establish non-dollar trade deals and alternative financial systems show more substantial progress compared to initiatives in the early 2000s. As the nature of the world system is anarchic, states make either individual or group efforts to guarantee their economic security and achieve their interests. Based on neoclassical realism, this paper analyzes both internal and external US economic factors driving current and future de-dollarization and the implications on the international monetary system, in addition to examining the motivation for such moves.

Keywords: de-dollarization, US dollar, monetary system, economic security, economic policies.

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2318 Investigation of Fire Damaged Concrete Using Nonlinear Resonance Vibration Method

Authors: Kang-Gyu Park, Sun-Jong Park, Hong Jae Yim, Hyo-Gyung Kwak

Abstract:

This paper attempts to evaluate the effect of fire damage on concrete by using nonlinear resonance vibration method, one of the nonlinear nondestructive method. Concrete exhibits not only nonlinear stress-strain relation but also hysteresis and discrete memory effect which are contained in consolidated materials. Hysteretic materials typically show the linear resonance frequency shift. Also, the shift of resonance frequency is changed according to the degree of micro damage. The degree of the shift can be obtained through nonlinear resonance vibration method. Five exposure scenarios were considered in order to make different internal micro damage. Also, the effect of post-fire-curing on fire-damaged concrete was taken into account to conform the change in internal damage. Hysteretic non linearity parameter was obtained by amplitude-dependent resonance frequency shift after specific curing periods. In addition, splitting tensile strength was measured on each sample to characterize the variation of residual strength. Then, a correlation between the hysteretic non linearity parameter and residual strength was proposed from each test result.

Keywords: nonlinear resonance vibration method, non linearity parameter, splitting tensile strength, micro damage, post-fire-curing, fire damaged concrete

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2317 Planning of Green Infrastructure on a City Level

Authors: James Li, Darko Joksimovic

Abstract:

Urban development changes the natural hydrologic cycle, resulting in storm water impacts such as flooding, water quality degradation, receiving water erosion, and ecosystem deterioration. An integrated storm water managementapproach utilizing source and conveyance (termed green infrastructure) and end-of-pipe control measures is an effective way to manage urban storm water impacts. This paper focuses onplanning green infrastructure (GI) at the source and along the drainage system on a city level. It consists of (1)geospatial analysis of feasible GI using physical suitability; (2) modelling of cumulative GI's stormwater performance; and (3) cost-effectiveness analysis to prioritize the implementation of GI. A case study of the City of Barrie in Ontario, Canada, was used to demonstrate the GI's planning.

Keywords: cost-effectiveness of storm water controls, green infrastructure, urban storm water, city-level master planning

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2316 Sailing/Anchoring: Home-making and Aspirations of Non-Majority Female Migrants in Shenzhen, China

Authors: Meiyun Meng

Abstract:

Urban China is now undergoing social transformation based on its rapid economic growth, developing its individualism and feminism. This paper approaches emergent relationships between female individuals’ everyday lives and urban China through internal migration, home-making practices and life-course perspectives. Focusing on Shenzhen, it explores how ten highly educated female migrants pursue aspirations of accommodating ‘non-majority’ identities, such as lesbians, divorced, or childless women, in urban China. Based on life stories and home video tours, this paper finds how these women develop non-majority lifestyles to negotiate their aspirations. On the one hand, they ‘sail’ away from past/present situations where collectivist and hetero-patriarchal norms marginalised their non-majority identities. On the other hand, they ‘anchor’ in places where ‘new’ socio-cultural contexts allow female individuals to pursue alternative opportunities and preferential lifestyles. This paper provides fresh insights to interpret the social transformation in urban China, under the collectivist culture and hetero-patriarchal norms, through the lens of individual everyday home-making practices.

Keywords: home-making practices, internal migration, highly educated women, shenzhen, transforming urban China

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2315 Effect of Tensile Strain on Microstructure of Irradiated Core Internal Material

Authors: Hygreeva Kiran Namburi, Anna Hojna, Edita Lecianova, Fencl Zdenek

Abstract:

Irradiation Assisted Stress Corrosion Cracking [IASCC] is one of the most significant environmental degradation in the internal components made from Austenitic stainless steel. This mechanism is still not fully understood and there are no suitable criteria for prediction of the damage during operation. In this work, core basket material 08Ch18N10T austenitic stainless steel acquired from decommissioned NPP Nord / Greifswald Unit 1, VVER 440-230 type, operated for 15 years and irradiated at 5.2 dpa is studied. This material was tensile tested at two different test temperatures and strain rates in air and at the elevated temperature under the water environment. SEM observations of the fracture surface documented ductile fracture of the samples tested in air, but areas of IASCC tested in water. This paper emphasizes on the microscopic examination results from the mechanically tested samples to determine the underlying IASCC physical damage process. TEM observations of thin foils made from the gauge sections that are closer to the fractured surface of the specimen aimed to find variances in interaction of dislocations and grain boundaries owing to different test conditions.

Keywords: irradiation assisted stress corrosion cracking, core basket material, SEM observations of the fracture surface, microscopic examination results

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2314 Range Suitability Model for Livestock Grazing in Taleghan Rangelands

Authors: Hossein Arzani, Masoud Jafari Shalamzari, Z. Arzani

Abstract:

This paper follows FAO model of suitability analysis. Influential factors affecting extensive grazing were determined and converted into a model. Taleghan rangelands were examined for common types of grazing animals as an example. Advantages and limitations were elicited. All range ecosystems’ components affect range suitability but due to the time and money restrictions, the most important and feasible elements were investigated. From which three sub-models including water accessibility, forage production and erosion sensitivity were considered. Suitable areas in four levels of suitability were calculated using GIS. This suitability modeling approach was adopted due to its simplicity and the minimal time that is required for transforming and analyzing the data sets. Managers could be benefited from the model to devise the measures more wisely to cope with the limitations and enhance the rangelands health and condition.

Keywords: range suitability, land-use, extensive grazing, modeling, land evaluation

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2313 Flexible Current Collectors for Printed Primary Batteries

Authors: Vikas Kumar

Abstract:

Portable batteries are reliable source of mobile energy to power smart wearable electronics, medical devices, communications, and others internet of thing (IoT) devices. There is a continuous increase in demand for thinner, more flexible battery with high energy density and reliability to meet the requirement. For a flexible battery, factors that affect these properties are the stability of current collectors, electrode materials and their interfaces with the corrosive electrolytes. State-of-the-art conventional and flexible batteries utilise carbon as an electrode and current collectors which cause high internal resistance (~100 ohms) and limit the peak current to ~1mA. This makes them unsuitable for a wide range of applications. Replacing the carbon parts with metallic components would reduce the internal resistance (and hence reduce parasitic loss), but significantly increases the risk of corrosion due to galvanic interactions within the battery. To overcome these challenges, low cost electroplated nickel (Ni) on copper (Cu) was studied as a potential anode current collector for a zinc-manganese oxide primary battery with different concentration of NH4Cl/ZnCl2 electrolyte. Using electrical impedance spectroscopy (EIS), we monitored the open circuit potential (OCP) of electroplated nickel (different thicknesses) in different concentration of electrolytes to optimise the thickness of Ni coating. Our results show that electroless Ni coating suffer excessive corrosion in these electrolytes. Corrosion rates of Ni coatings for different concentrations of electrolytes have been calculated with Tafel analysis. These results suggest that for electroplated Ni, channelling and/or open porosity is a major issue, which was confirmed by morphological analysis. These channels are an easy pathway for electrolyte to penetrate thorough Ni to corrode the Ni/Cu interface completely. We further investigated the incorporation of a special printed graphene layer on Ni to provide corrosion protection in this corrosive electrolyte medium. We find that the incorporation of printed graphene layer provides the corrosion protection to the Ni and enhances the chemical bonding between the active materials and current collector and also decreases the overall internal resistance of the battery system.

Keywords: corrosion, electrical impedance spectroscopy, flexible battery, graphene, metal current collector

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2312 The Attentional Focus Impact on the Decision Making in Three-Game Situations in Tennis

Authors: Marina Tsetseli, Eleni Zetou, Maria Michalopoulou, Nikos Vernadakis

Abstract:

Game performance, besides the accuracy and the quality skills execution, depends heavily on where the athletes will focus their attention while performing a skill. The purpose of the present study was to examine and compare the effect of internal and external focus of attention instructions on the decision making in tennis at players 8-9 years old (M=8.4, SD=0.49). The participants (N=40) were divided into two groups and followed an intervention training program that lasted 4 weeks; first group (N=20) under internal focus of attention instructions and the second group (N=20) under external focus of attention instructions. Three measurements took place (pre-test, post-test, and retention test) in which the participants were video recorded while playing matches in real scoring conditions. GPAI (Game Performance Assessment Instrument) was used to evaluate decision making in three game situations; service, return of the service, baseline game. ANOVA repeated measures (2 groups x 3 measurements) revealed a significant interaction between groups and measurements. Specifically, the data analysis showed superiority of the group that was instructed to focus externally. The high scores of the external attention group were maintained at the same level at the third measurement as well, which indicates that the impact was concerning not only performance but also learning. Thus, cues that lead to an external focus of attention enhance the decision-making skill and therefore the game performance of the young tennis players.

Keywords: decision making, evaluation, focus of attention, game performance, tennis

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2311 Propellant Less Propulsion System Using Microwave Thrusters

Authors: D. Pradeep Mitra, Prafulla

Abstract:

Looking to the word propellant-less system it makes us to believe that it is an impossible one, but this paper demonstrates the use of microwaves to create a system which makes impossible to be possible, it means a propellant-less propulsion system using microwaves. In these thrusters, microwaves are radiated into a sealed parabolic cavity through a waveguide, which act on the surface of the cavity and follow the axis of the thrusters to produce thrust. The advantages of these thrusters are: (1) Producing thrust without propellant; without erosion, wear, and thermal stress from the hot exhaust gas; and at the same time increasing quality. (2) If the microwave output power is stable, the performance of thrusters is not affected by its working environment. This paper is demonstrated from general maxwell equations. These equations are used to create the mathematical model of the thrusters. These mathematical model helps us to calculate the Q factor and calculate the approximate thrust which would be generated in the system.

Keywords: propellant less, microwaves, parabolic wave guide, propulsion system

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2310 Internal Cycles from Hydrometric Data and Variability Detected Through Hydrological Modelling Results, on the Niger River, over 1901-2020

Authors: Salif Koné

Abstract:

We analyze hydrometric data at the Koulikoro station on the Niger River; this basin drains 120600 km2 and covers three countries in West Africa, Guinea, Mali, and Ivory Coast. Two subsequent decadal cycles are highlighted (1925-1936 and 1929-1939) instead of the presumed single decadal one from literature. Moreover, the observed hydrometric data shows a multidecadal 40-year period that is confirmed when graphing a spatial coefficient of variation of runoff over decades (starting at 1901-1910). Spatial runoff data are produced on 48 grids (0.5 degree by 0.5 degree) and through semi-distributed versions of both SimulHyd model and GR2M model - variants of a French Hydrologic model – standing for Genie Rural of 2 parameters at monthly time step. Both extremal decades in terms of runoff coefficient of variation are confronted: 1951-1960 has minimal coefficient of variation, and 1981-1990 shows the maximal value of it during the three months of high-water level (August, September, and October). The mapping of the relative variation of these two decadal situations allows hypothesizing as following: the scale of variation between both extremal situations could serve to fix boundary conditions for further simulations using data from climate scenario.

Keywords: internal cycles, hydrometric data, niger river, gr2m and simulhyd framework, runoff coefficient of variation

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2309 Influence of Annealing on the Mechanical Properties of Polyester-Cotton Friction Spun Yarn

Authors: Sujit Kumar Sinha, R. Chattopadhyay

Abstract:

In the course of processing phases and use, fibres, yarns, or fabrics are subjected to a variety of stresses and strains, which cause the development of internal stresses. Given an opportunity, these inherent stresses try to bring back the structure to the original state. As an example, a twisted yarn always shows a tendency to untwist whenever its one end is made free. If the yarn is not held under tension, it may form snarls due to the presence of excessive torque. The running performance of such yarn or thread may, therefore, get negatively affected by it, as a snarl may not pass through the knitting or sewing needle smoothly, leading to an end break. A fabric shows a tendency to form wrinkles whenever squeezed. It may also shrink when brought to a relaxed state. In order to improve performance (i.e., dimensional stability or appearance), stabilization of the structure is needed. The stabilization can be attained through the release of internal stresses, which can be brought about by the process of annealing and/or other finishing treatments. When a fabric is subjected to heat, a change in the properties of the fibers, yarns, and fabric is expected. The degree to which the properties are affected would depend upon the condition of heat treatment and on the properties & structure of fibres, yarns, and fabric. In the present study, an attempt has been made to investigate the effect of annealing treatment on the properties of polyester cotton yarns with varying sheath structures.

Keywords: friction spun yarn, annealing, tenacity, structural integrity, decay

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2308 USA Commercial Pilots’ Views of Crew Resource Management, Social Desirability, and Safety Locus of Control

Authors: Stephen Vera, Tabitha Black, Charalambos Cleanthous, Ryan Sain

Abstract:

A gender comparison of USA commercial pilots’ demographics and views of CRM, social desirability and locus of control were surveyed. The Aviation safety locus of control (ASLOC) was used to measure external (ASLOC-E) or internal (ASLOC-I) aviation safety locus of control. The gender differences were explored using the ASLOC scores as a categorical variable. A differential comparison of crew resource management (CRM), based on the Federal Aviation Administration’s (FAA) guidelines was conducted. The results indicated that the proportion of female to male respondents matches the current ratio of USA commercial pilots. Moreover, there were no significant differences regarding overall education and the total number of communication classes one took. Regarding CRM issues, there were no significant differences on their views regarding the roles of the PIC, stress, time management, and managing a flight team. The females scored significantly lower on aeronautical decision making (ADM) and communications. There were no significant differences on either the Balanced Inventory of Desirable Responding (BIDR) impression management (IM) or self-deceptive enhancement (SDE). Although there were no overall significant differences on the ASLOC, the females did score higher on the internal subscale than did the males. An additional comparison of socially desirable responding indicates that all scores may be invalid, especially from the female respondents.

Keywords: social desirability, safety locus of control, crew resource management, commercial pilots

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2307 Effects of Coastal Structure Construction on Ecosystem

Authors: Afshin Jahangirzadeh, Shatirah Akib, Keyvan Kimiaei, Hossein Basser

Abstract:

Coastal defense structures were built to protect part of shore from beach erosion and flooding by sea water. Effects of coastal defense structures can be negative or positive. Some of the effects are beneficial in socioeconomic aspect, but environment matters should be given more concerns because it can bring bad consequences to the earth landscape and make the ecosystem be unbalanced. This study concerns on the negative impacts as they are dominant. Coastal structures can extremely impact the shoreline configuration. Artificial structures can influence sediment transport, split the coastal space, etc. This can result in habitats loss and lead to noise and visual disturbance of birds. There are two types of coastal defense structures, hard coastal structure and soft coastal structure. Both coastal structures have their own impacts. The impacts are induced during the construction, maintaining, and operation of the structures.

Keywords: ecosystem, environmental impact, hard coastal structures, soft coastal structures

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2306 Analyze Long-Term Shoreline Change at Yi-Lan Coast, Taiwan Using Multiple Sources

Authors: Geng-Gui Wang, Chia-Hao Chang, Jee-Cheng Wu

Abstract:

A shoreline is a line where a body of water and the shore meet. It provides economic and social security to coastal habitations. However, shorelines face multiple threats due to both natural processes and man-made effects because of disasters, rapid urbanization, industrialization, and sand deposition and erosion, etc. In this study, we analyzed multi-temporal satellite images of the Yilan coast, Taiwan from 1978 to 2016, using the United States Geological Survey (USGS) Digital Shoreline Analysis System (DSAS), weather information (as rainfall records and typhoon routes), and man-made construction project data to explore the causes of shoreline changes. The results showed that the shoreline at Yilan coast is greatly influenced by typhoons and anthropogenic interventions.

Keywords: shoreline change, multi-temporal satellite, digital shoreline analysis system, DSAS, Yi-Lan coast

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2305 Integral Abutment Bridge: A Study on Types, Importance, Limitations and Design Guidelines

Authors: Babitha Elizabeth Philip

Abstract:

This paper aims to study in general about bridges without expansion joints. Integral Abutment Bridges (IAB) fall into this category of bridges. They are having a continuous deck and also the girders are integrated into the abutments. They are most cost effective system in terms of construction, maintenance, and longevity. The main advantage of IAB is that it is corrosion resistant since water is not allowed to pass through the structure. The other attractions of integral bridges are its simple and rapid construction, smooth and uninterrupted deck which provides a safe ride. Also damages to the abutments can be avoided to a great extent due to better load distribution at the bridge ends. Damages due to improper drainage are not seen in IAB because of its properly drained approach slabs thus eliminating the possibility of erosion of the abutment backfill and freeze and thaw damage resulting from saturated backfill.

Keywords: continuous bridge, integral abutment bridge, joint bridge, life cycle cost, soil interaction

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2304 Protecting Migrants at Risk as Internally Displaced Persons: State Responses to Foreign Immigrants Displaced by Natural Disasters in Thailand, The United States, and Japan

Authors: Toake Endoh

Abstract:

Cross-border migration of people is a critical driver for sustainable economic development in the Asia-Pacific region. Meanwhile, the region is susceptible to mega-scale natural disasters, such as tsunami, earthquakes, and typhoons. When migrants are stranded in a foreign country by a disaster, who should be responsible for their safety and security? What legal or moral foundation is there to advocate for the protection and assistance of “migrants at risk (M@R)”? How can the states practice “good governance” in their response to displacement of the foreign migrants? This paper inquires how to protect foreign migrants displaced by a natural disaster under international law and proposes protective actions to be taken by of migrant-receiver governments. First, the paper discusses the theoretical foundation for protection of M@R and argues that the nation-states are charged of responsibility to protect at-risk foreigners as “internally displaced persons” in the light of the United Nations’ Guiding Principles of Internal Displacement (1998). Second, through the case study of the Kobe Earthquake in Japan (1995), the Tsunami in Thailand (2004), and the Hurricane Katrina in the U.S. (2005), the paper evaluates how effectively (or poorly) institutions and state actors addressed the specific vulnerability felt by M@R in these crises.

Keywords: internal displaced persons, natural disaster, international migration, responsibility to protect

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2303 Uncertainty in Near-Term Global Surface Warming Linked to Pacific Trade Wind Variability

Authors: M. Hadi Bordbar, Matthew England, Alex Sen Gupta, Agus Santoso, Andrea Taschetto, Thomas Martin, Wonsun Park, Mojib Latif

Abstract:

Climate models generally simulate long-term reductions in the Pacific Walker Circulation with increasing atmospheric greenhouse gases. However, over two recent decades (1992-2011) there was a strong intensification of the Pacific Trade Winds that is linked with a slowdown in global surface warming. Using large ensembles of multiple climate models forced by increasing atmospheric greenhouse gas concentrations and starting from different ocean and/or atmospheric initial conditions, we reveal very diverse 20-year trends in the tropical Pacific climate associated with a considerable uncertainty in the globally averaged surface air temperature (SAT) in each model ensemble. This result suggests low confidence in our ability to accurately predict SAT trends over 20-year timescale only from external forcing. We show, however, that the uncertainty can be reduced when the initial oceanic state is adequately known and well represented in the model. Our analyses suggest that internal variability in the Pacific trade winds can mask the anthropogenic signal over a 20-year time frame, and drive transitions between periods of accelerated global warming and temporary slowdown periods.

Keywords: trade winds, walker circulation, hiatus in the global surface warming, internal climate variability

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2302 Killing for the Great Peace: An Internal Perspective on the Anti-Manchu Theme in the Taiping Movement

Authors: Zihao He

Abstract:

The majority of existing studies on the Taiping Movement (1851-1864) viewed their anti-Manchu attitudes as nationalist agendas: Taiping was aimed at revolting against the Manchu government and establishing a new political regime. To explain these aggressive and violent attitudes towards Manchu, these studies mainly found socio-economic factors and stressed the status of “being deprived”. Even the ‘demon-slaying’ narrative of the Taiping to dehumanize the Manchu tends to be viewed as a “religious tool” to achieve their political, nationalist aim. This paper argues that these studies on Taiping’s anti-Manchu attitudes and behaviors are analyzed from an external angle and have two major problems. Firstly, they distinguished “religion” from “nationalist” or “political”, focusing on the “political” nature of the movement. “Religion” and the religious experience within Taiping were largely ignored. This paper argues that there was no separable and independent “religion” in the Taiping Movement, as opposed to secular, nationalist politics. Secondly, these analyses held an external perspective on Taiping’s anti-Manchu agenda. Demonizing and killing Manchu were viewed as purely political actions. On the contrary, this paper focuses on the internal perspective of anti-Manchu narratives in the Taiping Movement. The method of this paper is mainly textual analysis, focusing on the official documents, edicts, and proclamations of the Taiping movement. It views the writing of the Taiping as a coherent narrative and rhetoric, which was attractive and convincing for its followers. In terms of the main findings, firstly, internal and external perspectives on anti-Manchu violence are different. Externally, violence was viewed as a tool and necessary process to achieve the political goal. However, internally speaking, in Taiping’s writing, violence was a result of Godlessness, which would be solved as far as the faith in God is restored in China. Having a framework of universal love among human beings as sons and daughters of the Heavenly Father and killing was forbidden, the Taiping excluded Manchus from the family of human beings and demonized them. “Demon-slaying” was not violence. It was constructed as a necessary process to achieve the Great Peace. Moreover, Taiping’s anti-Manchu violence was not merely “political.” Rather, the category “religion” and its binary opposition, “secular,” is not suitable for Taiping. A key point related to this argument is the revolutionary violence against the Manchu government, which inherited the traditional “Heavenly Mandate” model. From an internal, theological perspective, anti-Manchu was ordained and commanded by the Heavenly Father. Manchu, as a regime, was standing as a hindrance in the path toward God. Besides, Manchu was not only viewed as a regime, but they were also “demons.” Therefore, the paper examines how Manchus were dehumanized in Taiping’s writings and were situated outside of the consideration of nonviolent and love. Manchu as a regime and Manchu as demons are in a dynamic relationship. As a regime, the Manchu government was preventing Chinese people from worshipping the Heavenly Father, so they were demonized. As they were demons, killing Manchus during the revolt was justified and not viewed as being contradicted the universal love among human beings.

Keywords: anti-manchu, demon-slaying, heavenly mandate, religion and violence, the taiping movement.

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2301 Managerial Leadership Styles of Deans in Indonesian Universities

Authors: Jenny Ngo, Harry De Boer, Jurgen Enders

Abstract:

Indonesian higher education has experienced significant changes over the last decade. In 1999, the government published an overall strategy for decentralization and enhancement of local autonomy in many sectors, including (higher) education. Indonesian higher education reforms have forced universities to restructure their internal university governance to become more entrepreneurial. These new types of internal university governance are likely to affect the institutions’ leadership and management. This paper discusses the approach and findings of a study on the managerial leadership styles of deans in Indonesian universities. The study aims to get a better understanding of styles exhibited by deans manifested in their behaviors. Using the theories of reasoned action and planned behavior, in combination with the competing values framework, a large-scale survey was conducted to gather information on the deans’ behaviors, attitudes, subjective norms, and perceived behavioral control. Based on the responses of a sample of 218 deans, the study identifies a number of leadership styles: the Master, the Competitive Consultant, the Consensual Goal-Setter, the Focused Team Captain, and the Informed Trust-Builder style. The study demonstrates that attitudes are the primary determinant of the styles that were found. Perceived behavioral control is a factor that explains some managerial leadership styles. By understanding the attitudes of deans in Indonesian universities, and their leadership styles, universities can strengthen their management and governance, and thus improve their effectiveness.

Keywords: deans, Indonesian higher education, leadership and management styles, decentralization

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2300 Boundary Layer Flow of a Casson Nanofluid Past a Vertical Exponentially Stretching Cylinder in the Presence of a Transverse Magnetic Field with Internal Heat Generation/Absorption

Authors: G. Sarojamma, K. Vendabai

Abstract:

An analysis is carried out to investigate the effect of magnetic field and heat source on the steady boundary layer flow and heat transfer of a Casson nanofluid over a vertical cylinder stretching exponentially along its radial direction. Using a similarity transformation, the governing mathematical equations, with the boundary conditions are reduced to a system of coupled, non –linear ordinary differential equations. The resulting system is solved numerically by the fourth order Runge – Kutta scheme with shooting technique. The influence of various physical parameters such as Reynolds number, Prandtl number, magnetic field, Brownian motion parameter, thermophoresis parameter, Lewis number and the natural convection parameter are presented graphically and discussed for non – dimensional velocity, temperature and nanoparticle volume fraction. Numerical data for the skin – friction coefficient, local Nusselt number and the local Sherwood number have been tabulated for various parametric conditions. It is found that the local Nusselt number is a decreasing function of Brownian motion parameter Nb and the thermophoresis parameter Nt.

Keywords: casson nanofluid, boundary layer flow, internal heat generation/absorption, exponentially stretching cylinder, heat transfer, brownian motion, thermophoresis

Procedia PDF Downloads 389
2299 An Equivalent Circuit Model Approach for Battery Pack Simulation in a Hybrid Electric Vehicle System Powertrain

Authors: Suchitra Sivakumar, Hajime Shingyouchi, Toshinori Okajima, Kyohei Yamaguchi, Jin Kusaka

Abstract:

The progressing need for powertrain electrification calls for more accurate and reliable simulation models. A battery pack serves as the most vital component for energy storage in an electrified powertrain. Hybrid electric vehicles (HEV) do not behave the same way as they age, and there are several environmental factors that account for the degradation of the battery on a system level. Therefore, in this work, a battery model was proposed to study the state of charge (SOC) variation and the internal dynamic changes that contribute to aging and performance degradation in HEV batteries. An equivalent circuit battery model (ECM) is built using MATLAB Simulink to investigate the output characteristics of the lithium-ion battery. The ECM comprises of circuit elements like a voltage source, a series resistor and a parallel RC network connected in series. A parameter estimation study is conducted on the ECM to study the dependencies of the circuit elements with the state of charge (SOC) and the terminal voltage of the battery. The battery model is extended to simulate the temperature dependence of the individual battery cell and the battery pack with the environment. The temperature dependence model accounts for the heat loss due to internal resistance build up in the battery pack during charging, discharging, and due to atmospheric temperature. The model was validated for a lithium-ion battery pack with an independent drive cycle showing a voltage accuracy of 4% and SOC accuracy of about 2%.

Keywords: battery model, hybrid electric vehicle, lithium-ion battery, thermal model

Procedia PDF Downloads 298
2298 Hygrothermal Assessment of Internally Insulated Prefabricated Concrete Wall in Polish Climatic Condition

Authors: D. Kaczorek

Abstract:

Internal insulation of external walls is often problematic due to increased moisture content in the wall and interstitial or surface condensation risk. In this paper, the hygrothermal performance of prefabricated, concrete, large panel, external wall typical for WK70 system, commonly used in Poland in the 70’s, with inside, additional insulation was investigated. Thermal insulation board made out of hygroscopic, natural materials with moisture buffer capacity and extruded polystyrene (EPS) board was used as interior insulation. Experience with this natural insulation is rare in Poland. The analysis was performed using WUFI software. First of all, the impact of various standard boundary conditions on the behavior of the different wall assemblies was tested. The comparison of results showed that the moisture class according to the EN ISO 13788 leads to too high values of total moisture content in the wall since the boundary condition according to the EN 15026 should be usually applied. Then, hygrothermal 1D-simulations were conducted by WUFI Pro for analysis of internally added insulation, and the weak point like the joint of the wall with the concrete ceiling was verified using 2D simulations. Results showed that, in the Warsaw climate and the indoor conditions adopted in accordance with EN 15026, in the tested wall assemblies, regardless of the type of interior insulation, there would not be any problems with moisture - inside the structure and on the interior surface.

Keywords: concrete large panel wall, hygrothermal simulation, internal insulation, moisture related issues

Procedia PDF Downloads 165
2297 Trend Analysis of Africa’s Entrepreneurial Framework Conditions

Authors: Sheng-Hung Chen, Grace Mmametena Mahlangu, Hui-Cheng Wang

Abstract:

This study aims to explore the trends of the Entrepreneurial Framework Conditions (EFCs) in the five African regions. The Global Entrepreneur Monitor (GEM) is the primary source of data. The data drawn were organized into a panel (2000-2021) and obtained from the National Expert Survey (NES) databases as harmonized by the (GEM). The Methodology used is descriptive and uses mainly charts and tables; this is in line with the approach used by the GEM. The GEM draws its data from the National Expert Survey (NES). The survey by the NES is administered to experts in each country. The GEM collects entrepreneurship data specific to each country. It provides information about entrepreneurial ecosystems and their impact on entrepreneurship. The secondary source is from the literature review. This study focuses on the following GEM indicators: Financing for Entrepreneurs, Government support and Policies, Taxes and Bureaucracy, Government programs, Basic School Entrepreneurial Education and Training, Post school Entrepreneurial Education and Training, R&D Transfer, Commercial And Professional Infrastructure, Internal Market Dynamics, Internal Market Openness, Physical and Service Infrastructure, and Cultural And Social Norms, based on GEM Report 2020/21. The limitation of the study is the lack of updated data from some countries. Countries have to fund their own regional studies; African countries do not regularly participate due to a lack of resources.

Keywords: trend analysis, entrepreneurial framework conditions (EFCs), African region, government programs

Procedia PDF Downloads 71
2296 Characterization the Internal Corrosion Behavior by Using Natural Inhibitor in Crude Oil of Low Carbon Steel Pipeline

Authors: Iman Adnan Annon, Kadhim F. Alsultan

Abstract:

This study investigate the internal corrosion of low carbon steel pipelines in the crude oil, as well as prepare and use natural and locally available plant as a natural corrosion inhibiter, the nature extraction achieved by two types of solvents in order to show the solvent effect on inhibition process, the first being distilled water and the second is diethyl ether. FT-IR spectra and using a chemical reagents achieved to detection the presence of many active groups and the presence of tannins, phenols, and alkaloids in the natural extraction. Some experiments were achieved to estimate the performance of a new inhibitor, one of these tests include corrosion measurement by simple immersion in crude oil within and without inhibitors which added in different amounts 30,40,50and 60 ppm at tow temperature 300 and 323k, where the best inhibition efficiencies which get when added the inhibitors in a critical amounts or closest to it, since for the aqueous extract (EB-A) the inhibition efficiency reached (94.4) and (86.71)% at 300 and 323k respectively, and for diethyl ether extract (EB-D) reached (82.87) and (84.6)% at 300 and 323k respectively. Optical microscopy examination have been conducted to evaluate the corrosion nature where it show a clear difference in the topography of the immersed samples surface after add the inhibitors at two temperatures. The results show that the new corrosion inhibitor is not only equivalent to a chemical inhibitor but has greatly improvement properties such as: high efficiency, low cost, non-toxic, easily to produce, and nonpolluting as compared with chemical inhibitor.

Keywords: corrosion in pipeline, inhibitors, crude oil, carbon steel, types of solvent

Procedia PDF Downloads 140
2295 Migration and Identity Erosion: An Exploratory Study of First Generation Nigerian-Americans

Authors: Lolade Siyonbola

Abstract:

Nigerians are often celebrated as being the most educated cultural group in America. The cultural values and history that have led to this reality are particular to a generation that came of age post colonialism. Many of these cultural values have been passed down from post-colonial parent to millennial child, but most have not. This study, based on interviews and surveys of Nigerian millennials and their parents in the United States, explores the degree to which identity has been eroded in the millennial generation due to a lack of imparted cultural values and knowledge from the previous generation. Most of the subjects do not speak their native language or identify with their cultural heritage sufficiently to build ties with their native land. Most are experiencing some degree of identity crisis, and therefore limited self-actualization, with little to no support; as there are few successful tools available to this population. If governmental programs to reverse these trends are not implemented within this generation, the implications to the individual, family and home nation (Nigeria), will be felt for generations to come.

Keywords: identity, culture, self-actualization, social identity theory, migration, transnationalism, value systems

Procedia PDF Downloads 372
2294 Application of the State of the Art of Hydraulic Models to Manage Coastal Problems, Case Study: The Egyptian Mediterranean Coast Model

Authors: Al. I. Diwedar, Moheb Iskander, Mohamed Yossef, Ahmed ElKut, Noha Fouad, Radwa Fathy, Mustafa M. Almaghraby, Amira Samir, Ahmed Romya, Nourhan Hassan, Asmaa Abo Zed, Bas Reijmerink, Julien Groenenboom

Abstract:

Coastal problems are stressing the coastal environment due to its complexity. The dynamic interaction between the sea and the land results in serious problems that threaten coastal areas worldwide, in addition to human interventions and activities. This makes the coastal environment highly vulnerable to natural processes like flooding, erosion, and the impact of human activities as pollution. Protecting and preserving this vulnerable coastal zone with its valuable ecosystems calls for addressing the coastal problems. This, in the end, will support the sustainability of the coastal communities and maintain the current and future generations. Consequently applying suitable management strategies and sustainable development that consider the unique characteristics of the coastal system is a must. The coastal management philosophy aims to solve the conflicts of interest between human development activities and this dynamic nature. Modeling emerges as a successful tool that provides support to decision-makers, engineers, and researchers for better management practices. Modeling tools proved that it is accurate and reliable in prediction. With its capability to integrate data from various sources such as bathymetric surveys, satellite images, and meteorological data, it offers the possibility for engineers and scientists to understand this complex dynamic system and get in-depth into the interaction between both the natural and human-induced factors. This enables decision-makers to make informed choices and develop effective strategies for sustainable development and risk mitigation of the coastal zone. The application of modeling tools supports the evaluation of various scenarios by affording the possibility to simulate and forecast different coastal processes from the hydrodynamic and wave actions and the resulting flooding and erosion. The state-of-the-art application of modeling tools in coastal management allows for better understanding and predicting coastal processes, optimizing infrastructure planning and design, supporting ecosystem-based approaches, assessing climate change impacts, managing hazards, and finally facilitating stakeholder engagement. This paper emphasizes the role of hydraulic models in enhancing the management of coastal problems by discussing the diverse applications of modeling in coastal management. It highlights the modelling role in understanding complex coastal processes, and predicting outcomes. The importance of informing decision-makers with modeling results which gives technical and scientific support to achieve sustainable coastal development and protection.

Keywords: coastal problems, coastal management, hydraulic model, numerical model, physical model

Procedia PDF Downloads 29
2293 Soil Reinforcement by Fibers Using Triaxial Compression Test

Authors: Negadi Kheira, Arab Ahmed, Kamal Elbokl Mohamed, Setti Fatima

Abstract:

In order to evaluate influences of roots on soil shear strength, monotonic drained and undrained triaxial laboratory tests were carried out on reconstituted specimens at various confining pressure (σc’=50, 100, 200, 300, 400 kPa) and a constant relative density (Dr = 50%). Reinforcement of soil by fibrous roots is crucial for preventing soil erosion and degradation. Therefore, we investigated soil reinforcement by roots of acacia planted in the area of Chlef where shallow landslides and slope instability are frequent. These roots were distributed in soil in two forms: vertically and horizontally. The monotonic test results showed that roots have more impacts on the soil shear strength than the friction angle, and the presence of roots in soil substantially increased the soil shear strength. Also, the results showed that the contribution of roots on the shear strength mobilized increases with increase in the confining pressure.

Keywords: soil, monotonic, triaxial test, root fiber, undrained

Procedia PDF Downloads 415