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Open Access
Book part
Publication date: 4 May 2018

Heriyanti, Lenny Marlinda, Rayandra Asyhar, Sutrisno and Marfizal

Purpose – This work aims to study the treatment of adsorbant on the increasing liquid hydrocarbon quality produced by pyrolysis low density polyethylene (LDPE) plastic waste at…

Abstract

Purpose – This work aims to study the treatment of adsorbant on the increasing liquid hydrocarbon quality produced by pyrolysis low density polyethylene (LDPE) plastic waste at low temperature. The hydrocarbon distribution, physicochemical properties and emission test were also studied due to its application in internal combustion engine. This research uses pure Calcium carbonate (CaCO3) and pure activated carbon as adsorbant, LDPE type clear plastic samples with control variable that is solar gas station.

Design/Methodology/Approach – LDPE plastic waste of 10 kg were vaporized in the thermal cracking batch reactor using LPG 12 kg as fuel at range temperature from 100 to 300°C and condensed into liquid hydrocarbon. Furthermore, this product was treated with the mixed CaCO3 and activated carbon as adsorbants to decrease contaminant material.

Findings – GC-MS identified the presence of carbon chain in the range of C6–C44 with 24.24% of hydrocarbon compounds in the liquid. They are similar to diesel (C6–C14). The 30% of liquid yields were found at operating temperature of 300°C. The calorific value of liquid was 46.021 MJ/Kg. This value was 5.07% higher than diesel as control.

Originality/Value – Hydrocarbon compounds in liquid produced by thermal cracking at a low temperature was similar to liquid from a catalytic process.

Details

Proceedings of MICoMS 2017
Type: Book
ISBN:

Keywords

Article
Publication date: 30 December 2022

Fatimah A.M. Al-Zahrani

The purpose of this study aims to synthesize a novel donor–acceptor dye based on phenothiazine as a donor (D) and nonconjugated spacer was devised and synthesized by condensing of…

Abstract

Purpose

The purpose of this study aims to synthesize a novel donor–acceptor dye based on phenothiazine as a donor (D) and nonconjugated spacer was devised and synthesized by condensing of 2,2'-(1H-indene-1,3(2H)-diylidene) dimalononitrile with aldehyde and the practical synthesis methodology as given in Scheme 1.

Design/methodology/approach

The prepared phenothiazine dye was systematically experimentally and theoretically examined and characterized using nuclear magnetic resonance spectroscopy (1H,13C NMR), Fourier-transform infrared spectroscopy (IR) and high-resolution mass spectrometry. Density functional theory (DFT) and time-dependent density functional theory DT-DFT calculations were implemented to determine the electronic properties of the new dye

Findings

The UV-Vis absorption and fluorescence spectroscopy of the synthesized dye was investigated in a variety of solvents with varying polarities to demonstrate positive solvatochromism correlated with intramolecular charge transfer (ICT). The probe’s quantum yields (Фf) are experimentally measured in ethanol, and the Stokes shifts are found to be in the 4846–9430 cm−1 range.

Originality/value

The findings depicted that the novel (D-π-A) chromophores may act as a significant factor in the organic optoelectronics.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 3 January 2017

Abderrazzak El Boukili

The purpose of this paper is to develop and apply accurate and original models to understand and analyze the effects of the fabrication temperatures on thermal-induced stress and…

Abstract

Purpose

The purpose of this paper is to develop and apply accurate and original models to understand and analyze the effects of the fabrication temperatures on thermal-induced stress and speed performance of nano positively doped metal oxide semiconductor (pMOS) transistors.

Design/methodology/approach

The speed performances of nano pMOS transistors depend strongly on the mobility of holes, which itself depends on the thermal-induced extrinsic stress σ. The author uses a finite volume method to solve the proposed system of partial differential equations needed to calculate the thermal-induced stress σ accurately.

Findings

The thermal extrinsic stress σ depends strongly on the thermal intrinsic stress σ0, thermal intrinsic strain ε0, elastic constants C11 and C12 and the fabrication temperatures. In literature, the effects of fabrication temperatures on C11 and C12 needed to calculate thermal-induced stress σ0 have been ignored. The new finding is that if the effects of fabrication temperatures on C11 and C12 are ignored, then, the values of stress σ0 and σ will be overestimated and, then, not accurate. Another important finding is that the speed performance of nano pMOS transistors will increase if the fabrication temperature of silicon-germanium films used as stressors is increased.

Practical implications

To predict correctly the thermal-induced stress and speed performance of nano pMOS transistors, the effects of fabrication temperatures on the elastic constants required to calculate the thermal-induced intrinsic stress σ0 should be taken into account.

Originality/value

There are three levels of originalities. The author considers the effects of the fabrication temperatures on extrinsic stress σ, intrinsic stress σ0 and elastic constants C11 and C12.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 January 2009

P.K. Yadawa and R.R. Yadav

A simple interaction‐potential model has been established to calculate the higher order elastic constants of intermetallic YbAl2 in the temperature range from 10‐300K. Temperature…

Abstract

A simple interaction‐potential model has been established to calculate the higher order elastic constants of intermetallic YbAl2 in the temperature range from 10‐300K. Temperature dependent second and third order elastic constants are used for the determination of the ultrasonic attenuation, velocity, Grüneisen numbers, Acoustic‐coupling constants, and thermal relaxation time at the different temperatures. Temperature dependency of the ultrasonic properties of YbAl2 is similar at low temperatures to that of pure metals and the low carrier heavy fermion systems ‐ LaSb, YbAs and YbP having simple NaCl‐type structures. Thermal energy density makes significant contribution to the total attenuation in the compound at the higher temperatures from 100‐300K. Effect of the magnetic field on the ultrasonic attenuation is also evaluated using the magneto resistance data. At 100K, the effect of the magnetic field becomes insignificant. The attenuation decreases with the field at 3K to 50K.

Details

Multidiscipline Modeling in Materials and Structures, vol. 5 no. 1
Type: Research Article
ISSN: 1573-6105

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Book part
Publication date: 1 August 2019

Nikolai G. Sinyavsky

The issues of development of decisions are very important during formation of the system of management of modern business systems in the conditions of turbulence of external…

Abstract

The issues of development of decisions are very important during formation of the system of management of modern business systems in the conditions of turbulence of external conditions. The ideas of rational structuring of information flows, which are used for decision making, are related to the necessity for development of communicative culture of companies. Quality of interaction between persons that participate in decision making should be assessed by analyzing the ratio of probabilities that characterize quality of information and correctness of decisions and development of a special model.

Details

Specifics of Decision Making in Modern Business Systems
Type: Book
ISBN: 978-1-78756-692-7

Keywords

Book part
Publication date: 10 February 2020

Özlem Kuvat and Burcu İşgüden Kılıç

The confidence in the qualifications and independence of the audit activities and professionals has been lost due to the financial scandals that have arisen over time. These…

Abstract

The confidence in the qualifications and independence of the audit activities and professionals has been lost due to the financial scandals that have arisen over time. These scandals in the accounting and auditing fields caused both enterprises and investors to suffer from large amounts of losses and thus the need for reliable financial statements and corporate governance increased.

Both investors and decision-makers need independent assurance to achieve transparent, reliable, and impartial financial information. The fulfillment of this requirement is possible through independent auditing activity and independent audit firms. Business management shall carry out the selection of independent auditors based on various criteria (fee, reputation, audit team, relations, etc.). In addition, it may also be necessary to periodically change an independent audit firm due to rotation or other reasons (fee, disputes, relationships, etc.).

In this study, a ranking of the importance level of the evaluation criteria, for the selection and change of the independent audit firm in an enterprise in Borsa İstanbul (BIST) 100 in Turkey, was conducted. Analytical Hierarchy Process (AHP), which is one of the multicriteria decision-making techniques, was used for ranking. In the hierarchy established for the selection of the independent audit firm, the main criteria of the “audit fee” and the “reputation and qualifications of the audit firm” have been established. According to the findings obtained as a result of binary comparisons, the first four ranks among sub-criteria are “provision of international service,” “quality of technical expertise of audit firm,” “industry expertise of audit firm,” and “suitability of fee offered by audit firm.”

For the change of audit firm, four main criteria “audit fee,” “disputes arising during the audit process,” “relations with the audit firm,” and “rotation” are taken into consideration. For sub-criteria, first four criteria were “rotation of independent audit firm,” “rotation of independent auditor,” “audit firm’s inability to adequately practice proactive audit approaches,” and “inadequate communication.”

Details

Contemporary Issues in Audit Management and Forensic Accounting
Type: Book
ISBN: 978-1-83867-636-0

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Book part
Publication date: 15 September 2022

Violeta Cvetkoska, Gokulananda Patel and Milanka Dimovska

Purpose: The purpose of this study is to reveal the readiness of the employees in the banking sector in the Republic of North Macedonia to adapt to the reorganisation of working…

Abstract

Purpose: The purpose of this study is to reveal the readiness of the employees in the banking sector in the Republic of North Macedonia to adapt to the reorganisation of working hours while at the same time using the safest payment methods in conditions when the world is trying to deal with the crisis caused by the COVID-19 virus.

Need for the study: The world is rapidly moving towards increasing digitalisation, which is part of all spheres of human life. The outbreak of the COVID-19 virus pandemic has accelerated these processes by requiring people to adapt to the new conditions. The countries that have worked rapidly to digitise the system, while massively using non-cash payments, have adapted more easily to their regular daily tasks. The Republic of North Macedonia, as a developing country, is trying to take a step forward by introducing the innovations used by developed countries, taking into account the available assets and human resources.

Methodology: A method for qualitative forecasting, Delphi, is used in three rounds, and the gained insights serve as inputs in the creation of two analytic hierarchy process (AHP) models.

Findings: From the extensive analysis we performed, we found that the lack of digitalisation and process automation made it difficult for employees to adapt to the method of working from home, and on the other hand, they had a much easier time adapting to the use of alternative distribution channels.

Practical implications: Our findings are useful for the country, regulatory bodies and the bank’s management in developing strategies and plans for working from home or reorganisation of working hours, to be more acceptable to employees, emphasising the benefits for both employees and employers. Also, researchers and management practitioners in developing countries interested in this area can follow our combined Delphi-AHP approach in conducting similar research.

Details

The New Digital Era: Digitalisation, Emerging Risks and Opportunities
Type: Book
ISBN: 978-1-80382-980-7

Keywords

Book part
Publication date: 21 November 2014

Kyungchul Song

When a parameter of interest is nondifferentiable in the probability, the existing theory of semiparametric efficient estimation is not applicable, as it does not have an…

Abstract

When a parameter of interest is nondifferentiable in the probability, the existing theory of semiparametric efficient estimation is not applicable, as it does not have an influence function. Song (2014) recently developed a local asymptotic minimax estimation theory for a parameter that is a nondifferentiable transform of a regular parameter, where the transform is a composite map of a continuous piecewise linear map with a single kink point and a translation-scale equivariant map. The contribution of this paper is twofold. First, this paper extends the local asymptotic minimax theory to nondifferentiable transforms that are a composite map of a Lipschitz continuous map having a finite set of nondifferentiability points and a translation-scale equivariant map. Second, this paper investigates the discontinuity of the local asymptotic minimax risk in the true probability and shows that the proposed estimator remains to be optimal even when the risk is locally robustified not only over the scores at the true probability, but also over the true probability itself. However, the local robustification does not resolve the issue of discontinuity in the local asymptotic minimax risk.

Book part
Publication date: 25 April 2022

Do Tien Sy, Zwe Man Aung and Nguyen Thanh Viet

Claims and disputes are often unavoidable in the construction industry due to its unique and complex characteristics involving the massive investment of capital, lengthy project

Abstract

Claims and disputes are often unavoidable in the construction industry due to its unique and complex characteristics involving the massive investment of capital, lengthy project duration, and multiple project stakeholders. This chapter intends to identify the critical construction claims attributes, compare the perceptions of major stakeholders on different claim attributes, and investigate the contrast of the top five claim attributes between this study and previous ones. The literature review resulted in 48 claim attributes responsible for the construction project schedule delays. These attributes were then presented to Vietnam construction industry (VCI) practitioners in the form of a questionnaire survey. Data analysis was done based on the collected 113 qualified samples. Relative importance index (RII) was applied to determine the ranking of claim attributes. The results were that the top five causes of claims, that is, payment delays, mistakes by contractor during construction stage, delays in work progress by the contractor, financial failure of the contractor, and frequently changing requirements by the owner, lead to the schedule delays in VCI. These findings can assist the local industry practitioners and foreign companies seeking a share in the VCI market in understanding the causes of construction claims comprehensively and formulating the countermeasures to minimise their impacts and hence reduce the unnecessary losses and raise the likelihood of success as well as maintain sustainable relationships among stakeholders.

Details

Sustainability Management Strategies and Impact in Developing Countries
Type: Book
ISBN: 978-1-80262-450-2

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Book part
Publication date: 10 April 2019

Christopher S. Henry and Tamás Ilyés

For central banks who study the use of cash, acceptance of card payments is an important factor. Surveys to measure levels of card acceptance and the costs of payments can be…

Abstract

For central banks who study the use of cash, acceptance of card payments is an important factor. Surveys to measure levels of card acceptance and the costs of payments can be complicated and expensive. In this paper, we exploit a novel data set from Hungary to see the effect of stratified random sampling on estimates of payment card acceptance and usage. Using the Online Cashier Registry, a database linking the universe of merchant cash registers in Hungary, we create merchant and transaction level data sets. We compare county (geographic), industry and store size stratifications to simulate the usual stratification criteria for merchant surveys and see the effect on estimates of card acceptance for different sample sizes. Further, we estimate logistic regression models of card acceptance/usage to see how stratification biases estimates of key determinants of card acceptance/usage.

Details

The Econometrics of Complex Survey Data
Type: Book
ISBN: 978-1-78756-726-9

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