Search results for: local characteristic
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6756

Search results for: local characteristic

2016 Antifungal Activity of Medicinal Plants Used Traditionally for the Treatment of Fungal Infections and Related Ailments in South Africa

Authors: T. C. Machaba, S. M. Mahlo

Abstract:

The current study investigates the antifungal properties of crude plant extracts from selected medicinal plant species. Eight plant species used by the traditional healers and local people to treat fungal infections were selected for further phytochemical analysis and biological assay. The selected plant species were extracted with solvent of various polarities such as acetone, methanol, ethanol, hexane, dichloromethane, ethyl acetate and water. Leaf, roots and bark extracts of Maerua juncea Pax, Albuca seineri (Engl & K. Krause) J.C Manning & Goldblatt, Senna italica Mill., Elephantorrhiza elephantina (Burch.) Skeels, Indigofera circinata Benth., Schinus molle L., Asparagus buchananii Bak., were screened for antifungal activity against three animal fungal pathogens (Candida albicans, Aspergillus fumigatus and Cryptococcus neoformans). All plant extracts were active against the tested microorganisms. Acetone, dichloromethane, hexane and ethanol extracts of Senna italica and Elephantorrhiza elephantine had excellent activity against Candida albicans and A. fumigatus with the lowest MIC value of 0.02 mg/ml. Bioautography assay was used to determine the number of antifungal compounds presence in the plant extracts. No active compounds were observed in plant extracts of Indigofera circinnata, Schinus molle and Pentarrhinum insipidum with good antifungal activity against C. albicans and A. fumigatus indicating possible synergism between separated metabolites.

Keywords: antifungal activity, bioautography, ethnobotanical survey, minimum inhibitory concentration

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2015 Joint Replenishment and Heterogeneous Vehicle Routing Problem with Cyclical Schedule

Authors: Ming-Jong Yao, Chin-Sum Shui, Chih-Han Wang

Abstract:

This paper is developed based on a real-world decision scenario that an industrial gas company that applies the Vendor Managed Inventory model and supplies liquid oxygen with a self-operated heterogeneous vehicle fleet to hospitals in nearby cities. We name it as a Joint Replenishment and Heterogeneous Vehicle Routing Problem with Cyclical Schedule and formulate it as a non-linear mixed-integer linear programming problem which simultaneously determines the length of the planning cycle (PC), the length of the replenishment cycle and the dates of replenishment for each customer and the vehicle routes of each day within PC, such that the average daily operation cost within PC, including inventory holding cost, setup cost, transportation cost, and overtime labor cost, is minimized. A solution method based on genetic algorithm, embedded with an encoding and decoding mechanism and local search operators, is then proposed, and the hash function is adopted to avoid repetitive fitness evaluation for identical solutions. Numerical experiments demonstrate that the proposed solution method can effectively solve the problem under different lengths of PC and number of customers. The method is also shown to be effective in determining whether the company should expand the storage capacity of a customer whose demand increases. Sensitivity analysis of the vehicle fleet composition shows that deploying a mixed fleet can reduce the daily operating cost.

Keywords: cyclic inventory routing problem, joint replenishment, heterogeneous vehicle, genetic algorithm

Procedia PDF Downloads 88
2014 Generation of Renewable Energy Through Photovoltaic Panels, Albania Photovoltaic Capacity

Authors: Dylber Qema

Abstract:

Driven by recent developments in technology and the growing concern about the sustainability and environmental impact of conventional fuel use, the possibility of producing clean and sustainable energy in significant quantities from renewable energy sources has sparked interest all over the world. Solar energy is one of the sources for the generation of electricity, with no emissions or environmental pollution. The electricity produced by photovoltaics can supply a home or business and can even be sold or exchanged with the grid operator. A very positive effect of using photovoltaic modules is that they do not produce greenhouse gases and do not produce chemical waste, unlike all other forms of energy production. Photovoltaics are becoming one of the largest investments in the field of renewable generating units. Improving the reliability of the electric power system is one of the most important impacts of the installation of photovoltaics (PV). Renewable energy sources are so large that they can meet the energy demands of the whole world, thus enabling sustainable supply as well as reducing local and global atmospheric emissions. Albania is rated by experts as one of the most favorable countries in Europe for the production of electricity from solar panels. But the country currently produces about 1% of its energy from the sun, while the rest of the needs are met by hydropower plants and imports. Albania has very good characteristics in terms of solar radiation (about 1300–1400 kW/m2). Solar energy has great potential and is a permanent source of energy with greater economic efficiency. Photovoltaic energy is also seen as an alternative, as long periods of drought in Albania have produced crises and high costs for securing energy in the foreign market.

Keywords: capacity, ministry of tourism and environment, obstacles, photovoltaic energy, sustainable

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2013 Community’s Role in Slum Development: A Case Study of the Kabul Old City

Authors: Habibi Said Mustafa, Hiroko Ono

Abstract:

Kabul, the capital of Afghanistan, has witnessed a major population growth in the last decades which caused a significant increase in the number of informal settlements. The residents are suffering from many problems such as poor infrastructure, shortage of public facilities, depriving of the sense of ownership and facing much environmental degradation. Even though majority of the residents are living in such condition, the government response has been quite weak. The government’s main planning strategy has been upgrading in the form of provision of facilities and improving elements of physical infrastructure, unfortunately most of the projects which had not community’s support, faced with lots of challenges such as people’s resistance or even in some cases the project rather than solving the problem, compounded them to a worse condition. A major reason as to why many projects have not been effective in achieving certain objectives in the past is the results of local people were not being involved. Community participation plays an important role in slum development projects. The development of an integrated urban development concept these days without the mobilization of participants and community seems difficult and impossible. Therefore this paper looks into factors and methods which can help in creating a participatory approach for developing the slums in Kabul city. Furthermore, it describes the result of a questionnaire which was conducted on a part of the Kabul Old City due to hear resident’s problem related to the slum upgrading and collect their opinions on this regard. The research also points out some factors which can severely hamper the successful implementation of a slum upgrading project if not adequately addressed.

Keywords: Community empowerment, Informal settlements, Job opportunities, People participation

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2012 Unconventional Explorers: Gen Z Travelers Redefinding the Travel Experience

Authors: M. Panidou, F. Kilipiris, E. Christou, K. Alexandris

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This study intends to investigate the travel preferences of Generation Z (born between 1996 and 2012), focusing on their inclination towards unique and unconventional travel experiences, prioritization of authentic cultural immersion and local experiences over traditional tourist attractions, and their value for flexibility and spontaneity in travel plans. By examining these aspects, the research aims to provide insights into the preferences and behaviors of Generation Z travelers, contributing to a better understanding of their travel choices and informing the tourism industry in catering to their needs and desires. Secondary data was gathered from academic literature and industry reports to offer a thorough study of the topic. A quantitative method was used, and primary data was collected through an online questionnaire. One hundred Greek people between the ages of eighteen and twenty-seven were the study's sample. SPSS software was used to assist in the analysis of the data. The findings of the research showed that Gen Z is attracted to unusual and distinctive travel experiences, prioritizing genuine cultural immersion over typical tourist attractions, and they highly value flexibility in their travel decision-making. This research contributes to a deeper understanding of how Gen Z travelers are reshaping the travel industry. Travel companies, marketers, and destination management organizations will find the findings useful in adjusting their products to suit this influential demographic's changing demands and preferences. Considering the limitations of the sample size, future studies could expand the sample size to include individuals from different cultural backgrounds for a more comprehensive understanding.

Keywords: cultural immersion, flexibility, generation Z, travel preferences, unique experiences

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2011 Integrating Accreditation and Quality Assurance Exercises into the Quranic School System in the South-Western Nigeria

Authors: Popoola Sulaimon Akorede, Muinat A. Agbabiaka-Mustapha

Abstract:

The Quranic / piazza school where the rudiments of Islam are being imparted from the teaching of Arabic/ Quranic alphabets which later metamorphosized to higher fundamental principles of Islam is the major determinant of the existence of Islam in any part of south western Nigeria. In other words, one can successfully say that where there is a few or non-existence of such schools in that part of the country, the practice of the religion of Islam would be either very low or not existing at all. However, it has been discovered in the modern worlds that several challenges are militating against the development of these schools and among these challenges are poor admission policy, inadequate facilities such as learning environment and instructional materials, curriculum inadequacy and the management and the administration of the schools which failed to change in order to meet the modern contemporary Educational challenges. The focus of this paper therefore is to improve the conditions of these basic Islamic schools through the introduction of quality assurance and integrating accreditation Exercise to improve their status in order to enhance economic empowerment and to further their educational career in the future so that they will be able to compete favourably among the graduates of conventional universities. The scope of this study is limited to only seven (7) states of yorubaland and with only three (3) proprietors/ schools from each state which are Lagos, Oyo, Ogun, Osun, Ekiti, Ondo and parts of Kwara State. The study revealed that quality assurance as well as accreditation exercise are lacking in all the local Arabic/Quranic schools. Suggestions are proffered towards correcting the anomalies in these schools so that they can meet the modern Educational standard.

Keywords: accreditation, quality assurance, Quranic schools, South-western Nigeria

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2010 A Study on Shavadoon Underground Living Space in Dezful and Shooshtar Cities, Southwest of Iran: As a Sample of Sustainable Vernacular Architecture

Authors: Haniyeh Okhovat, Mahmood Hosseini, Omid Kaveh Ahangari, Mona Zaryoun

Abstract:

Shavadoon is a type of underground living space, formerly used in urban residences of Dezful and Shooshtar cities in southwestern Iran. In spite of their high efficiency in creating cool spaces for hot summers of that area, Shavadoons were abandoned, like many other components of vernacular architecture, as a result of the modernism movement. However, Shavadoons were used by the local people as shelters during the 8-year Iran-Iraq war, and although several cases of bombardment happened during those years, no case of damage was reported in those two cities. On this basis, and regarding the high seismicity of Iran, the use of Shavadoons as post-disasters shelters can be considered as a good issue for research. This paper presents the results of a thorough study conducted on these spaces and their seismic behavior. First, the architectural aspects of Shavadoon and their construction technique are presented. Then, the results of seismic evaluation of a sample Shavadoon, conducted by a series of time history analyses, using Plaxis software and a set of selected earthquakes, are briefly explained. These results show that Shavadoons have good stability against seismic excitations. This stability is mainly because of the high strength of conglomerate materials inside which the Shavadoons have been excavated. On this basis, and considering other merits of this components of vernacular architecture in southwest of Iran, it is recommended that the revival of these components is seriously reconsidered by both architects and civil engineers.

Keywords: Shavadoon, Iran high seismicity, Conglomerate, Modeling in Plaxis, Vernacular sustainable architecture

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2009 Whether Buffer Zone Community Forests’ Benefits Are Distributed Fairly to Low-Income Users: Reflection From the Buffer Zone Community Forests in Bardia National Park, Nepal

Authors: Keshav Raj Acharya, Thakur Silwal, Neelam C. Poudyal

Abstract:

Buffer zones, the peripheral areas around the national parks and wildlife reserves, are available for the purpose of benefitting the local inhabitants by providing forest products for subsistence needs of basic forest products outside the protected areas. The forest area within the buffer zone has been managed as a buffer zone community forest (BZCF) for the last 25 years after the approval of the buffer zone management regulation 1996. With a case study of select BZCF in Bardia National Park, this study aims to analyze whether the benefit provided by BZCF is equally available to poor users among other socioeconomic classes of the users. The findings are based on the analysis of cross-sectional data involving household surveys (n=305) and key informants’ interviews (n=10) as well as office records available at different 5 buffer zone community forest user groups offices. Results indicate that despite the provisions of subsidized rates for poor; poor households were more deprived due to higher forest products price particularly, the timber price in buffer zone. Evidence also indicate that due to the increased forest coverage, the incidence of wildlife damage has also increased and impacted the poor more due to lack of land ownership as well as limited alternatives. Clear community forest management guidelines with equitable benefit sharing and compensatory mechanisms to the users of poor socioeconomic class have been identified as a solution to increase the benefit to poor users in BZCFUGs.

Keywords: crop depredation, forest products, users, wellbeing ranking

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2008 Dry Season Rice Production along Hadejia Valley Irrigation Scheme in Auyo Local Government Area in Jigawa State

Authors: Saifullahi Umar, Baba Mamman Yarima, Mohammed Bello Usman, Hassan Mohammed

Abstract:

This study was conducted along with the Hadejia valley project irrigation under the Hadejia-Jama’are River Basin Development Authority (HRBDA) in Jigawa State. The multi-stage sampling procedure was used to select 72 rice farmers operating along with the Hadejia Valley Irrigation Project. Data for the study were collected using a structured questionnaire. The analytical tools employed for the study were descriptive statistics and Farm budget technique. The result shows that 55% of the farmers were between 31-40 years of age, 66.01% were male, and the result also revealed that the total cost of cultivation of an acre of land for rice production during the dry season was N73,900 with input cost accounting for 63.59% of the total cost of production. The gross return was N332,500, with a net return of N258,600 per acre. The estimated benefit-cost ratio of 3.449 indicates the strong performance of the dry season rice production. The leading constraints to dry season rice production were low access to quality extension services, low access to finance, poor quality fertilizers, and poor prices. The study, therefore, concludes that dry season rice production is a profitable enterprise in the study area hence, to productivity the farmers should be linked to effective extension service delivery institutions, expanding their access to productive sources of finances, the government should strengthen fertilizer quality control measures and comprehensive market linkages for the farmers.

Keywords: Auyo, dry season, Hadejia Valley, rice

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2007 Parameter Identification Analysis in the Design of Rock Fill Dams

Authors: G. Shahzadi, A. Soulaimani

Abstract:

This research work aims to identify the physical parameters of the constitutive soil model in the design of a rockfill dam by inverse analysis. The best parameters of the constitutive soil model, are those that minimize the objective function, defined as the difference between the measured and numerical results. The Finite Element code (Plaxis) has been utilized for numerical simulation. Polynomial and neural network-based response surfaces have been generated to analyze the relationship between soil parameters and displacements. The performance of surrogate models has been analyzed and compared by evaluating the root mean square error. A comparative study has been done based on objective functions and optimization techniques. Objective functions are categorized by considering measured data with and without uncertainty in instruments, defined by the least square method, which estimates the norm between the predicted displacements and the measured values. Hydro Quebec provided data sets for the measured values of the Romaine-2 dam. Stochastic optimization, an approach that can overcome local minima, and solve non-convex and non-differentiable problems with ease, is used to obtain an optimum value. Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Differential Evolution (DE) are compared for the minimization problem, although all these techniques take time to converge to an optimum value; however, PSO provided the better convergence and best soil parameters. Overall, parameter identification analysis could be effectively used for the rockfill dam application and has the potential to become a valuable tool for geotechnical engineers for assessing dam performance and dam safety.

Keywords: Rockfill dam, parameter identification, stochastic analysis, regression, PLAXIS

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2006 Transnational Migration of Sports Workers from Africa to Foreign Countries: The Impact of their Assistance to the Domestic Community Through their Socioeconomic Choices of Action

Authors: Ernest Yeboah Acheampong, Malek Bouhaouala, Michel Raspaud

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Studies on African sport workers’ migration have given less attention to examining the extent to which the individual (sports workers) contributes to a socio-economic development of their domestic communities. The decision to support or not to support can also have a debilitating effect on the domestic communities. This article therefore, analyses the choices of action of these actors with an exact focus on footballers to the domestic community. This exploratory survey focuses on 13 UEFA countries leagues of footballers from 43 African countries, including seventeen interviews and four autobiographies of the players. Max Weber theory of individual subjectivity can underpin their decisions making processes to either offer assistance or not to their locales. This study revealed some players closed relationships, particularly those raised in the typical locales as they often provide support via projects like building hospitals, schools, sporting facilities, health centres, and scholarship schemes among others. While others shown commitment and readiness to offer assistance, touch livelihood, and promote social development based on their lived experiences abroad. With many lamenting against lack of support from local and national authorities as disincentive to do more yet committed to the cause of the society. This article can conclude that football athletes logics of action depend on the individual values and conceptions from evidence of their socio-economic projects, as well as social embeddedness in the locality

Keywords: choices of action, domestic development, footballers, transnational migration

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2005 Electrochemical Properties of Li-Ion Batteries Anode Material: Li₃.₈Cu₀.₁Ni₀.₁Ti₅O₁₂

Authors: D. Olszewska, J. Niewiedzial

Abstract:

In some types of Li-ion batteries carbon in the form of graphite is used. Unfortunately, carbon materials, in particular graphite, have very good electrochemical properties, but increase their volume during charge/discharge cycles, which may even lead to an explosion of the cell. The cell element may be replaced by a composite material consisting of lithium-titanium oxide Li4Ti5O12 (LTO) modified with copper and nickel ions and carbon derived from sucrose. This way you can improve the conductivity of the material. LTO is appropriate only for applications which do not require high energy density because of its high operating voltage (ca. 1.5 V vs. Li/Li+). Specific capacity of Li4Ti5O12 is high enough for utilization in Li-ion batteries (theoretical capacity 175 mAh·g-1) but it is lower than capacity of graphite anodes. Materials based on Li4Ti5O12 do not change their volume during charging/discharging cycles, however, LTO has low conductivity. Another positive aspect of the use of sucrose in the carbon composite material is to eliminate the addition of carbon black from the anode of the battery. Therefore, the proposed materials contribute significantly to environmental protection and safety of selected lithium cells. New anode materials in order to obtain Li3.8Cu0.1Ni0.1Ti5O12 have been prepared by solid state synthesis using three-way: i) stoichiometric composition of Li2CO3, TiO2, CuO, NiO (A- Li3.8Cu0.1Ni0.1Ti5O12); ii) stoichiometric composition of Li2CO3, TiO2, Cu(NO3)2, Ni(NO3)2 (B-Li3.8Cu0.1Ni0.1Ti5O12); and iii) stoichiometric composition of Li2CO3, TiO2, CuO, NiO calcined with 10% of saccharose (Li3.8Cu0.1Ni0.1Ti5O12-C). Structure of materials was studied by X-ray diffraction (XRD). The electrochemical properties were performed using appropriately prepared cell Li|Li+|Li3.8Cu0.1Ni0.1Ti5O12 for cyclic voltammetry and discharge/charge measurements. The cells were periodically charged and discharged in the voltage range from 1.3 to 2.0 V applying constant charge/discharge current in order to determine the specific capacity of each electrode. Measurements at various values of the charge/discharge current (from C/10 to 5C) were carried out. Cyclic voltammetry investigation was carried out by applying to the cells a voltage linearly changing over time at a rate of 0.1 mV·s-1 (in the range from 2.0 to 1.3 V and from 1.3 to 2.0 V). The XRD method analyzes show that composite powders were obtained containing, in addition to the main phase, 4.78% and 4% TiO2 in A-Li3.8Cu0.1Ni0.1O12 and B-Li3.8Cu0.1Ni0.1O12, respectively. However, Li3.8Cu0.1Ni0.1O12-C material is three-phase: 63.84% of the main phase, 17.49 TiO2 and 18.67 Li2TiO3. Voltammograms of electrodes containing materials A-Li3.8Cu0.1Ni0.1O12 and B-Li3.8Cu0.1Ni0.1O12 are correct and repeatable. Peak cathode occurs for both samples at a potential approx. 1.52±0.01 V relative to a lithium electrode, while the anodic peak at potential approx. 1.65±0.05 V relative to a lithium electrode. Voltammogram of Li3.8Cu0.1Ni0.1Ti5O12-C (especially for the first measurement cycle) is not correct. There are large variations in values of specific current, which are not characteristic for materials LTO. From the point of view of safety and environmentally friendly production of Li-ion cells eliminating soot and applying Li3.8Cu0.1Ni0.1Ti5O12-C as an active material of an anode in lithium-ion batteries seems to be a good alternative to currently used materials.

Keywords: anode, Li-ion batteries, Li₄O₅O₁₂, spinel

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2004 Sergei Prokofiev and Ukraine: The Influence of the Ukrainian Musical Tradition

Authors: Khrystyna Zai

Abstract:

This research delves into the profound impact of Ukrainian musical traditions on the life and works of the renowned composer Sergei Prokofiev. Sergei Prokofiev's formative years in Ukraine, particularly in Sontsivka(Eastern Ukraine), allowed him to immerse himself in the local music. He encountered Ukrainian folk songs and dances, which left an indelible mark on his musical sensibilities. With a focus on the early 20th century, a period of significant cultural transformation in both Ukraine and Europe, this study examines how Prokofiev's exposure to Ukrainian folk music, its melodic motifs, and rhythmic patterns influenced his compositions. Prokofiev’s works showcase his deliberate efforts to fuse Ukrainian elements with his distinctive modernist style. This study analyzes Prokofiev's engagement with Ukrainian themes in his music, such as the "Semen Kotko”, “The Love of Three Oranges”, “On the Dnieper”, “Scythian Suite”, “Sinfonia Concertante" for cello and orchestra, "Sonata No. 9,", “Partisans in the steppes of Ukraine” (where Prokofiev uses texts in Ukrainian). The scientific work mentions his interactions and collaborations with Ukrainian musicians and cultural figures during Prokofiev’s career. Notably, his association with Ukrainian pianist Sviatoslav Richter and conductor Kirill Karabits led to interpretations of his compositions with a Ukrainian perspective. This research illuminates the nuances of cross-cultural influences in Prokofiev's oeuvre, contributing to a deeper understanding of the interplay between national identities and artistic expression during a pivotal period in history, based on the fact that the composer himself considered Ukraine to be his homeland, calling himself “steppe boy”.

Keywords: florida atlantic university, ukrainian music, ukrainian composer, sergei prokofiev

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2003 Building Collapse: Factors and Resisting Mechanisms: A Review of Case Studies

Authors: Genevieve D. Fernandes, Nisha P. Naik

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All through the ages in all human civilizations, men have been engaged in construction activity, not only to build their dwellings and house their activities, but also roads, bridges to facilitate means of transport, and communication etc. The main concern in this activity was to ensure safety and reduce the collapse of the buildings and other structures. But even after taking all precautions, it is impossible to guarantee safety and collapse because of several unforeseen reasons like faulty constructions, design errors, overloading, soil liquefaction, gas explosion, material degradation, terrorist attacks and economic factors also contributing to the collapse. It is also uneconomical to design the structure for unforeseen events unless they have a reasonable chance of occurrence. In order to ensure safety and prevent collapse, many guidelines have been framed by local bodies and government authorities in many countries like the United States Department of Defence (DOD), United States General Service Administration (GSA) and Euro-Codes in European Nations. Some other practices are followed to incorporate redundancies in the structure like detailing, ductile designs, tying of elements at particular locations, and provision of hinges and interconnections. It is also to be admitted that a full-proof safe design structure for accidental events cannot be prepared and implemented as it is uneconomical and the chances of such occurrences are less. This paper reviews past case studies of the collapse of structures with the aim of developing an understanding of the collapse mechanism. This study will definitely help to bring about a detailed improvement in the design to maximise the quality of the construction at a minimal cost.

Keywords: unforeseen factors, progressive collapse, collapse resisting mechanisms, column removal scenario

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2002 Phytoremediation Aeration System by Using Water Lettuce (Pistia Stratiotes I) Based on Zero Waste to Reduce the Impact of Industrial Liquid Waste in Jember, Indonesia

Authors: Wahyu Eko Diyanto, Amalia Dyah Arumsari, Ulfatu Layinatinnahdiyah Arrosyadi

Abstract:

Tofu industry is one of the local food industry which is can being competitive industry in the ASEAN Economic Community (AEC). However, a lot of tofu entrepreneurs just thinking how to produce good quality product without considering the impact of environmental conditions from the production process. Production of tofu per day requires a number of 15 kg with liquid waste generated is 652.5 liters. That liquid waste is discharged directly into waterways, whereas tofu liquid waste contains organic compounds that quickly unraveled, so it can pollute waterways. In addition, tofu liquid waste is high in Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), nitrogen and phosphorus. This research is aim to create a method of handling liquid waste effectively and efficiently by using water lettuce. The method is done by observation and experiment by using phytoremediation method in the tofu liquid waste using water lettuce and adding aeration to reduce the concentration of contaminants. The results of the research analyzed the waste quality standard parameters based on SNI (National Standardization Agency of Indonesia). The efficiency concentration and parameters average of tofu liquid waste are obtained pH 3,42% (from 4,0 to be 3,3), COD 76,13% (from 3579 ppm to be 854 ppm), BOD 55 % (from 11600 ppm to be 5242 ppm), TSS 93,6% (from 3174 ppm to be 203 ppm), turbidity is 64,8% (from 977 NTU to be 1013 NTU), and temperature 36oC (from 45oC to be 40oC). The efficiency of these parameters indicates a safe value for the effluent to be channeled in waterways. Water lettuce and tofu liquid waste phytoremediation result will be used as biogas as renewable energy.

Keywords: aeration, phytoremediation, water letuce, tofu liquid waste

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2001 Bio-Detoxification of Mycotoxins by Lactic Acid Bacteria from Different Food Matrices

Authors: António Inês, Ana Guimarães, José Maria, Vânia Laranjo, Armando Venâncio, Luís Abrunhosa

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Lactic acid bacteria (LAB) play a key role in the biopreservation of a wide range of fermented food products, such as yogurt, cheese, fermented milks, meat, fish, vegetables (sauerkraut, olives and pickles), certain beer brands, wines and silage, allowing their safe consumption, which gave to these bacteria a GRAS (Generally Recognised as Safe) status. Besides that, the use of LAB in food and feed is a promising strategy to reduce the exposure to dietary mycotoxins, improving their shelf life and reducing health risks, given the unique mycotoxin decontaminating characteristic of some LAB. Mycotoxins present carcinogenic, mutagenic, teratogenic, neurotoxic and immunosuppressive effects over animals and Humans, being the most important ochratoxin A (OTA), aflatoxins (AFB1), trichothecenes, zearalenone (ZEA), fumonisin (FUM) and patulin. In a previous work of our group it was observed OTA biodegradation by some strains of Pediococcus parvulus isolated from Douro wines. So, the aim of this study was to enlarge the screening of the biodetoxification over more mycotoxins besides OTA, including AFB1, and ZEA. This ability was checked in a collection of LAB isolated from vegetable (wine, olives, fruits and silage) and animal (milk and dairy products, sausages) sources. All LAB strains were characterized phenotypically (Gram, catalase) and genotypically. Molecular characterisation of all LAB strains was performed using genomic fingerprinting by MSP-PCR with (GTG)5 and csM13 primers. The identification of the isolates was confirmed by 16S rDNA sequencing. To study the ability of LAB strains to degrade OTA, AFB1 and ZEA, a MRS broth medium was supplemented with 2.0 μg/mL of each mycotoxin. For each strain, 2 mL of MRS supplemented with the mycotoxins was inoculated in triplicate with 109 CFU/mL. The culture media and bacterial cells were extracted by the addition of an equal volume of acetonitrile/methanol/acetic acid (78:20:2 v/v/v) to the culture tubes. A 2 mL sample was then collected and filtered into a clean 2 mL vial using PP filters with 0.45 μm pores. The samples were preserved at 4 °C until HPLC analysis. Among LAB tested, 10 strains isolated from milk were able to eliminate AFB1, belonging to Lactobacillus casei (7), Lb. paracasei (1), Lb. plantarum (1) and 1 to Leuconostoc mesenteroides. Two strains of Enterococcus faecium and one of Ec. faecalis from sausage eliminated ZEA. Concerning to strains of vegetal origin, one Lb. plantarum isolated from elderberry fruit, one Lb. buchnerii and one Lb. parafarraginis both isolated from silage eliminated ZEA. Other 2 strains of Lb. plantarum from silage were able to degrade both ZEA and OTA, and 1 Lb. buchnerii showed activity over AFB1. These enzymatic activities were also verified genotypically through specific gene PCR and posteriorly confirmed by sequencing analysis. In conclusion, due the ability of some strains of LAB isolated from different sources to eliminate OTA, AFB1 and ZEA one can recognize their potential biotechnological application to reduce the health hazards associated with these mycotoxins. They may be suitable as silage inoculants or as feed additives or even in food industry.

Keywords: bio-detoxification, lactic acid bacteria, mycotoxins, food and feed

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2000 Improving Waste Recycling and Resource Productivity by Integrating Smart Resource Tracking System

Authors: Atiq Zaman

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The high contamination rate in the recycling waste stream is one of the major problems in Australia. In addition, a lack of reliable waste data makes it even more difficult for designing and implementing an effective waste management plan. This article conceptualizes the opportunity to improve resource productivity by integrating smart resource tracking system (SRTS) into the Australian household waste management system. The application of the smart resource tracking system will be implemented through the following ways: (i) mobile application-based resource tracking system used to measure the household’s material flow; (ii) RFID, smart image and weighing system used to track waste generation, recycling and contamination; (iii) informing and motivating manufacturer and retailers to improve their problematic products’ packaging; and (iv) ensure quality and reliable data through open-sourced cloud data for public use. The smart mobile application, imaging, radio-frequency identification (RFID) and weighing technologies are not new, but the very straightforward idea of using these technologies in the household resource consumption, waste bins and collection trucks will open up a new era of accurately measuring and effectively managing our waste. The idea will bring the most urgently needed reliable, data and clarity on household consumption, recycling behaviour and waste management practices in the context of available local infrastructure and policies. Therefore, the findings of this study would be very important for decision makers to improve resource productivity in the waste industry by using smart resource tracking system.

Keywords: smart devices, mobile application, smart sensors, resource tracking, waste management, resource productivity

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1999 Critical Approach to Define the Architectural Structure of a Health Prototype in a Rural Area of Brazil

Authors: Domenico Chizzoniti, Monica Moscatelli, Letizia Cattani, Luca Preis

Abstract:

A primary healthcare facility in developing countries should be a multifunctional space able to respond to different requirements: Flexibility, modularity, aggregation and reversibility. These basic features could be better satisfied if applied to an architectural artifact that complies with the typological, figurative and constructive aspects of the context in which it is located. Therefore, the purpose of this paper is to identify a procedure that can define the figurative aspects of the architectural structure of the health prototype for the marginal areas of developing countries through a critical approach. The application context is the rural areas of the Northeast of Bahia in Brazil. The prototype should be located in the rural district of Quingoma, in the municipality of Lauro de Freitas, a particular place where there is still a cultural fusion of black and indigenous populations. Based on the historical analysis of settlement strategies and architectural structures in spaces of public interest or collective use, this paper aims to provide a procedure able to identify the categories and rules underlying typological and figurative aspects, in order to detect significant and generalizable elements, as well as materials and constructive techniques typically adopted in the rural areas of Brazil. The object of this work is therefore not only the recovery of certain constructive approaches but also the development of a procedure that integrates the requirements of the primary healthcare prototype with its surrounding economic, social, cultural, settlement and figurative conditions.

Keywords: architectural typology, developing countries, local construction techniques, primary health care.

Procedia PDF Downloads 324
1998 Numerical Analysis of NOₓ Emission in Staged Combustion for the Optimization of Once-Through-Steam-Generators

Authors: Adrien Chatel, Ehsan Askari Mahvelati, Laurent Fitschy

Abstract:

Once-Through-Steam-Generators are commonly used in the oil-sand industry in the heavy fuel oil extraction process. They are composed of three main parts: the burner, the radiant and convective sections. Natural gas is burned through staged diffusive flames stabilized by the burner. The heat generated by the combustion is transferred to the water flowing through the piping system in the radiant and convective sections. The steam produced within the pipes is then directed to the ground to reduce the oil viscosity and allow its pumping. With the rapid development of the oil-sand industry, the number of OTSG in operation has increased as well as the associated emissions of environmental pollutants, especially the Nitrous Oxides (NOₓ). To limit the environmental degradation, various international environmental agencies have established regulations on the pollutant discharge and pushed to reduce the NOₓ release. To meet these constraints, OTSG constructors have to rely on more and more advanced tools to study and predict the NOₓ emission. With the increase of the computational resources, Computational Fluid Dynamics (CFD) has emerged as a flexible tool to analyze the combustion and pollutant formation process. Moreover, to optimize the burner operating condition regarding the NOx emission, field characterization and measurements are usually accomplished. However, these kinds of experimental campaigns are particularly time-consuming and sometimes even impossible for industrial plants with strict operation schedule constraints. Therefore, the application of CFD seems to be more adequate in order to provide guidelines on the NOₓ emission and reduction problem. In the present work, two different software are employed to simulate the combustion process in an OTSG, namely the commercial software ANSYS Fluent and the open source software OpenFOAM. RANS (Reynolds-Averaged Navier–Stokes) equations combined with the Eddy Dissipation Concept to model the combustion and closed by the k-epsilon model are solved. A mesh sensitivity analysis is performed to assess the independence of the solution on the mesh. In the first part, the results given by the two software are compared and confronted with experimental data as a mean to assess the numerical modelling. Flame temperatures and chemical composition are used as reference fields to perform this validation. Results show a fair agreement between experimental and numerical data. In the last part, OpenFOAM is employed to simulate several operating conditions, and an Emission Characteristic Map of the combustion system is generated. The sources of high NOₓ production inside the OTSG are pointed and correlated to the physics of the flow. CFD is, therefore, a useful tool for providing an insight into the NOₓ emission phenomena in OTSG. Sources of high NOₓ production can be identified, and operating conditions can be adjusted accordingly. With the help of RANS simulations, an Emission Characteristics Map can be produced and then be used as a guide for a field tune-up.

Keywords: combustion, computational fluid dynamics, nitrous oxides emission, once-through-steam-generators

Procedia PDF Downloads 113
1997 Effects of the Different Recovery Durations on Some Physiological Parameters during 3 X 3 Small-Sided Games in Soccer

Authors: Samet Aktaş, Nurtekin Erkmen, Faruk Guven, Halil Taskin

Abstract:

This study aimed to determine the effects of 3 versus 3 small-sided games (SSG) with different recovery times on soma physiological parameters in soccer players. Twelve soccer players from Regional Amateur League volunteered for this study (mean±SD age, 20.50±2.43 years; height, 177.73±4.13 cm; weight, 70.83±8.38 kg). Subjects were performing soccer training for five days per week. The protocol of the study was approved by the local ethic committee in School of Physical Education and Sport, Selcuk University. The subjects were divided into teams with 3 players according to Yo-Yo Intermittent Recovery Test. The field dimension was 26 m wide and 34 m in length. Subjects performed two times in a random order a series of 3 bouts of 3-a-side SSGs with 3 min and 5 min recovery durations. In SSGs, each set were performed with 6 min duration. The percent of maximal heart rate (% HRmax), blood lactate concentration (LA) and Rated Perceived Exertion (RPE) scale points were collected before the SSGs and at the end of each set. Data were analyzed by analysis of variance (ANOVA) with repeated measures. Significant differences were found between %HRmax in before SSG and 1st set, 2nd set, and 3rd set in both SSG with 3 min recovery duration and SSG with 5 min recovery duration (p<0.05). Means of %HRmax in SSG with 3 min recovery duration at both 1st and 2nd sets were significantly higher than SSG with 5 min recovery duration (p<0.05). No significant difference was found between sets of either SSGs in terms of LA (p>0.05). LA in SSG with 3 min recovery duration was higher than SSG with 5 min recovery duration at 2nd sets (p<0.05). RPE in soccer players was not different between SSGs (p>0.05).In conclusion, this study demonstrates that exercise intensity in SSG with 3 min recovery durations is higher than SSG with 5 min recovery durations.

Keywords: small-sided games, soccer, heart rate, lactate

Procedia PDF Downloads 465
1996 Choosing the Lesser Evil: Tribal Alignment Formation in Civil Wars

Authors: Busra Nur Ozguler Aktel

Abstract:

This research aims to understand the factors that affect the ways in which tribes perceive and respond to violent conflicts in fragile states, given that tribes are essential stakeholders in many conflict-ridden fragile states, whether Afghanistan, Iraq, Syria, Libya, Somalia, Nigeria, or Yemen. It explores the primary questions of why some tribes align with extremist groups while others align with states during civil wars and why some tribes switch alignments. It argues that tribes form and switch alignments based on their perception of threats to their traditional tribal structure (internal dynamics) and clientelist relationships (external dynamics). Put differently; threat perceptions lead them to choose either the state or extremist groups that will more likely secure their traditional structure and patronage networks. This study focuses on Iraqi tribes as a case study. It builds a theory of tribal alignment formation based on ethnographic fieldwork in the Middle East, with a particular focus on Iraqi Sunni tribes living in the Kurdish region of Iraq and Jordan. As a result of the interviews with tribal leaders and members, local journalists, researchers, and politicians, it concludes that complex (re)alignments of tribes can determine the course and outcome of the conflicts, either mitigating or escalating violence. This study contributes to the larger body of conflict management and peacebuilding literature by introducing tribes as non-state actors and exploring their interactions with other actors in civil wars.

Keywords: civil wars, tribes, alignment formation, side-switching, Iraq

Procedia PDF Downloads 87
1995 Key Challenges Facing the Management of Archaeological and Tourism Sites in Jordan

Authors: Muna Slehat

Abstract:

Jordan is endowed with over 14,500 productive archaeological sites and also a wealth of heritage sites that need to be protected from the pressing threat of destruction and damage. Archaeological sites in Jordan face significant threats, including insensitive development, urbanization, pollution, tourism, and vandalism, therefore an effective management plan is a key element, not only for the conservation of this heritage, but also to address issues such as tourism and sustainable development. This study highlights the obstacles that confront the management of the archaeological and tourism sites in Jordan, prior to and after the launch of the Strategies for Management of Jordan’s Archaeological Heritage by the Department of Antiquities (DoA) 2007-2010 and 2014-2018, as well as the establishment of the Directorate of the Management of Archaeological Sites in 2010, and instructions for the proper use of tourism sites, 2014, by the Ministry of Tourism and Antiquities (MoTA). The study has revealed that the management of the archaeological and tourism sites under the pretext of improvement of services for tourists and visitors to Jordan would allow access to so-called polarization tourism and facilitate tourism development that would be sustainable economically and provide attractive returns. The data required have been collected through conducting interviews with 18 specialists. The main findings of the study are that management is new in Jordan, and has become a vital and dynamic force in Jordan after 2000 but that there have also been many mistakes, with sustainability of the sites being ignored and a lack of awareness among local communities surrounding these sites. Management of the sites has also suffered from a lack of organizational vision, with no instructions for practical application and no legislative provisions which cater for the efficient management of the sites. All of this needs to be amended to remove gaps, overlaps and ambiguities, so that the authorities responsible for the rehabilitation and promotion, development and management of these sites can overcome the problems, such as lack of human resources (specialists) and financial resources.

Keywords: Jordan, management, archaeological sites, tourism, challenges

Procedia PDF Downloads 311
1994 A Geogpraphic Overview about Offshore Energy Cleantech in Portugal

Authors: Ana Pego

Abstract:

Environmental technologies were developed for decades. Clean technologies emerged a few years ago. In these perspectives, the use of cleantech technologies has become very important due the fact of new era of environmental feats. As such, the market itself has become more competitive, more collaborative towards a better use of clean technologies. This paper shows the importance of clean technologies in offshore energy sector in Portuguese market, its localization and its impact on economy. Clean technologies are directly related with renewable cluster and concomitant with economic and social resource optimization criteria, geographic aspects, climate change and soil features. Cleantech is related with regional development, socio-technical transitions in organisations. There are an economical and social combinations which allow specialisation of regions in activities, higher employment, reduce of energy costs, local knowledge spillover and, business collaboration and competitiveness. The methodology used will be quantitative (IO matrix for Portugal 2013) and qualitative (questionnaires to stakeholders). The mix of both methodologies will confirm whether the use of technologies will allow a positive impact on economic and social variables used on this model. It is expected a positive impact on Portuguese economy both in investment and employment taking in account the localization of offshore renewable activities. This means that the importance of offshore renewable investment in Portugal has a few points which should be pointed out: the increase of specialised employment, localization of specific activities in territory, and increase of value added in certain regions. The conclusion will allow researchers and organisation to compare the Portuguese model to other European regions in order to a better use of natural and human resources.

Keywords: cleantech, economic impact, localisation, territory dynamics

Procedia PDF Downloads 228
1993 Consumers’ Trust and Values towards Halal Food Products in Malaysia

Authors: A. B. Elistina, S. Norhafifah, R. N. Nashaqilla, M. A. Afida Mastura., O. Mohhidin

Abstract:

The issue of halal, especially in food products, raises lots of concern among Muslim consumers. Halal is often associated with safe, clean and nutritious food, according to the principle of halal toyyiban. Apart from that, the importance of halal food is not only emphasized by Muslim consumers but also non-Muslims. This is because the halal product is something that has been recognized for its cleanliness and safety. Nevertheless, consumers often face problems to ensure that the products they buy are genuinely halal as they can only rely on the certification of the authorities. However, the issue is the extent to which consumers place trust in the responsible certification authorities to determine the status of halal for a product. Therefore, this paper is intended to identify the relationship between consumer values and trust towards responsible parties such as Department of Islamic Development Malaysia (JAKIM), the Ministry of Health (MOH), foreign halal certification body and producers with consumers’ behavior. Apart from that, this study will also determine the value which consumers hold when choosing halal food and its relationship with consumers’ behavior. The total of 400 respondents who had been selected through stratified random sampling had participated in this study, and the data were collected through a set of self-administered questionnaire. The results showed that trust towards JAKIM is the highest, followed by trust towards MOH, foreign Halal certification agency and lastly the producers. Meanwhile, the values associated with halal foods are the quality, followed by emotional, economic and lastly social values. Results show that all factors can explain 20.3% variance in consumers’ behavior when consuming halal food products and trust towards the producers become the main determinant factor. Therefore, this study is expected to help the certification authorities local or abroad to inculcate trust among consumers as well as assisting food products manufacturers to enhance the halal food industry in Malaysia.

Keywords: behavior, consumers, halal food, trust, value

Procedia PDF Downloads 408
1992 Evolutionary Swarm Robotics: Dynamic Subgoal-Based Path Formation and Task Allocation for Exploration and Navigation in Unknown Environments

Authors: Lavanya Ratnabala, Robinroy Peter, E. Y. A. Charles

Abstract:

This research paper addresses the challenges of exploration and navigation in unknown environments from an evolutionary swarm robotics perspective. Path formation plays a crucial role in enabling cooperative swarm robots to accomplish these tasks. The paper presents a method called the sub-goal-based path formation, which establishes a path between two different locations by exploiting visually connected sub-goals. Simulation experiments conducted in the Argos simulator demonstrate the successful formation of paths in the majority of trials. Furthermore, the paper tackles the problem of inter-collision (traffic) among a large number of robots engaged in path formation, which negatively impacts the performance of the sub-goal-based method. To mitigate this issue, a task allocation strategy is proposed, leveraging local communication protocols and light signal-based communication. The strategy evaluates the distance between points and determines the required number of robots for the path formation task, reducing unwanted exploration and traffic congestion. The performance of the sub-goal-based path formation and task allocation strategy is evaluated by comparing path length, time, and resource reduction against the A* algorithm. The simulation experiments demonstrate promising results, showcasing the scalability, robustness, and fault tolerance characteristics of the proposed approach.

Keywords: swarm, path formation, task allocation, Argos, exploration, navigation, sub-goal

Procedia PDF Downloads 42
1991 Theatrical Architecture in Bologna at the Beginning of the Twentieth Century: The Renaissance of Modernissimo Cinema

Authors: Giorgia Predari, Riccardo Gulli

Abstract:

The paper describes the history and the stylistic choices adopted in the construction of Palazzo Ronzani in Bologna, which was the first building to rise after the heavy demolitions carried out in the historical center of the city at the beginning of the twentieth century. In 1910, the local administration adopted a detailed plan to change the aspect of the city, as it was already happening in the main European capitals. In this context, starting from 1911, the architect and scenographer Gualtiero Pontoni designed for Alessandro Ronzani -the owner of a well-known Bolognese beer company- his Palazzo, which is listed among the first multifunctional buildings in Bologna, containing offices, commercial activities, and entertainment spaces. In an area of about 2000 m², the architect was able to propose a theatre with a capacity of 2000 seats at the basement, shops, a cafè-chantant and a restaurant on the ground floor, clubs, studios and commercial stores on the mezzanine and the first plan, and a hotel on the upper floors. The whole core of the building, at the underground levels, consisted of a reinforced concrete frame (one of the first examples of this type of construction in the city), which allowed the hall to have a free span of 11 x 12 meters, and a height of about 9 meters. Used until 2007 as a cinema, the hall has remained then in disuse for almost 10 years, but now an important functional restoration project with a strong architectural and scenographic value is taking place. It will bring the spaces back to the original geometries, in a historical and artistic condition inspired by the styles of the early Twentieth century.

Keywords: Modernissimo, Palazzo Ronzani, liberty, Bologna

Procedia PDF Downloads 121
1990 Hybrid Adaptive Modeling to Enhance Robustness of Real-Time Optimization

Authors: Hussain Syed Asad, Richard Kwok Kit Yuen, Gongsheng Huang

Abstract:

Real-time optimization has been considered an effective approach for improving energy efficient operation of heating, ventilation, and air-conditioning (HVAC) systems. In model-based real-time optimization, model mismatches cannot be avoided. When model mismatches are significant, the performance of the real-time optimization will be impaired and hence the expected energy saving will be reduced. In this paper, the model mismatches for chiller plant on real-time optimization are considered. In the real-time optimization of the chiller plant, simplified semi-physical or grey box model of chiller is always used, which should be identified using available operation data. To overcome the model mismatches associated with the chiller model, hybrid Genetic Algorithms (HGAs) method is used for online real-time training of the chiller model. HGAs combines Genetic Algorithms (GAs) method (for global search) and traditional optimization method (i.e. faster and more efficient for local search) to avoid conventional hit and trial process of GAs. The identification of model parameters is synthesized as an optimization problem; and the objective function is the Least Square Error between the output from the model and the actual output from the chiller plant. A case study is used to illustrate the implementation of the proposed method. It has been shown that the proposed approach is able to provide reliability in decision making, enhance the robustness of the real-time optimization strategy and improve on energy performance.

Keywords: energy performance, hybrid adaptive modeling, hybrid genetic algorithms, real-time optimization, heating, ventilation, and air-conditioning

Procedia PDF Downloads 417
1989 Understanding of Malaysian Community Disaster Resilience: Australian Scorecard Adaptation

Authors: Salizar Mohamed Ludin, Mohd Khairul Hasyimi Firdaus, Paul Arbon

Abstract:

Purpose: This paper aims to develop Malaysian Government and community-level critical thinking, planning and action for improving community disaster resilience by reporting Phase 1, Part 1 of a larger community disaster resilience measurement study about adapting the Torrens Resilience Institute Australian Community Disaster Resilience Scorecard to the Malaysian context. Methodology: Pparticipatory action research encouraged key people involved in managing the six most affected areas in the 2014 flooding of Kelantan in Malaysia’s north-east to participate in discussions about adapting and self-testing the Australian Community Disaster Resilience Scorecard to measure and improve their communities’ disaster resilience. Findings: Communities need to strengthen their disaster resilience through better communication, cross-community cooperation, maximizing opportunities to compare their plans, actions and reactions with those reported in research publications, and aligning their community disaster management with reported best practice internationally while acknowledging the need to adapt such practice to local contexts. Research implications: There is a need for a Malaysia-wide, simple-to-use, standardized disaster resilience scorecard to improve the quality, quantity and capability of healthcare and emergency services’ preparedness, and to facilitate urgent reallocation of aid. Value: This study is the first of its kind in Malaysia. The resulting community disaster resilience guideline based on participants’ feedback about the Kelantan floods and scorecard self-testing has the potential for further adaptation to suit contexts across Malaysia, as well as demonstrating how the scorecard can be adapted for international use.

Keywords: community disaster resilience, CDR Scorecard, participatory action research, flooding, Malaysia

Procedia PDF Downloads 336
1988 Investigation of Resistive Switching in CsPbCl₃ / Cs₄PbCl₆ Core-Shell Nanocrystals Using Scanning Tunneling Spectroscopy: A Step Towards High Density Memory-based Applications

Authors: Arpan Bera, Rini Ganguly, Raja Chakraborty, Amlan J. Pal

Abstract:

To deal with the increasing demands for the high-density non-volatile memory devices, we need nano-sites with efficient and stable charge storage capabilities. We prepared nanocrystals (NCs) of inorganic perovskite, CsPbCl₃ coated with Cs₄PbCl₆, by colloidal synthesis. Due to the type-I band alignment at the junction, this core-shell composite is expected to behave as a charge trapping site. Using Scanning Tunneling Spectroscopy (STS), we investigated voltage-controlled resistive switching in this heterostructure by tracking the change in its current-voltage (I-V) characteristics. By applying voltage pulse of appropriate magnitude on the NCs through this non-invasive method, different resistive states of this system were systematically accessed. For suitable pulse-magnitude, the response jumped to a branch with enhanced current indicating a high-resistance state (HRS) to low-resistance state (LRS) switching in the core-shell NCs. We could reverse this process by using a pulse of opposite polarity. These two distinct resistive states can be considered as two logic states, 0 and 1, which are accessible by varying voltage magnitude and polarity. STS being a local probe in space enabled us to capture this switching at individual NC site. Hence, we claim a bright prospect of these core-shell NCs made of inorganic halide perovskites in future high density memory application.

Keywords: Core-shell perovskite, CsPbCl₃-Cs₄PbCl₆, resistive switching, Scanning Tunneling Spectroscopy

Procedia PDF Downloads 89
1987 The Influence of Viscosifier Concentration on Rheological Properties of Invert Emulsion Mud

Authors: Suzan Ibrahim

Abstract:

Oil-based muds are the most regularly used rotary drilling methods in the oil and gas industry. However, they have a negative impact on the environment, which leads to restrictions of their application in many countries of the world. Consequently, looking for new eco-friendly alternative formulations of oil-based drilling fluids for the exploration of troublesome formations. As one of the developments of Novel formulation of environmentally friendly drilling fluids and investigation of the formulation for jatropha oil-based drilling fluid samples at different concentrations of viscosifiers such as low viscosity polyanionic cellulose (PAC- LV), high viscosity polyanionic cellulose (PAC-V) and local Egyptian bentonite. The oil-water ratio was taken as 70:30, which is beneficial in producing a low fluid loss. 15 drilling fluid samples were formulated different concentrations of bentonite, PAC- LV and PAC-V individually and their mud density, rheological properties, electrical stability and filtration loss properties were determined. The rheological performance showed at higher concentrations of viscosifier, the trend of viscosity increment of PAC performed in a similar way to bentonite. The best result of electrical stability by using the lowest concentration of viscosifier was achieved with PAC-V. The lowest fluid loss volumes were obtained by using the highest concentrations (4 g) of viscosifiers. Mud cake thickness of samples increased by using viscosifiers; however, a lower range was achieved compared to API specification. From the overall experiment, it can be concluded that as the concentrations of viscosifier increase, the viscosity trend increase in a similar way to both PAC-V and bentonite. But we must note that the PAC-V is a more environmentally friendly additive and a renewable resource, cheaper than bentonite and improves properties of eco-friendly OBMs well. It is a preferable choice for oil-based drilling fluids.

Keywords: invert emulsion mud, oil-based mud, rheological properties, viscosifier

Procedia PDF Downloads 170