Maintenance and Physical Asset Management Issues in Project Commissioning

This study describes the review on maintenance related issues during design and construction stage within construction industry. The paper highlights the causes and errors made during design and construction stage and their impact during the operation/production/occupancy stage as well as the maintenance costs associated with it. The study identifies the mistakes in the working processes within design and construction stage leading to the errors that affect the durability, performance, reliability, maintainability, availability and safety of the systems. The paper presents a comprehensive review of the published literatures, journals, technical papers in the related areas in the construction field. The review highlights the new approaches and decision framework which link the designers and construction personnel that could reduce the errors and defects in construction which then lead to maintenance issues and asset management. The factors of accessibility, materials, design and documentation standardization have been discussed thoroughly for better understanding in improving maintenance and physical asset management in project commissioning

Performance of sludge palm oil combustion using waste oil burner

Sludge palm oil (SPO) is one of the wastes produced during the activity of palm oil milling process. The most common method to synthesise biodiesel from SPO is through a chemical process known as esterification and transesterification. The chemical process required additional cost and time. Hence this paper aims to evaluate the utilisation of SPO directly as fuel in burner system and compare with conventional diesel. The SPO studied contain free fatty acid (FFA) content about 30 %, density and viscosity at 0.982 g/cm3 and 67.76 mm2/s respectively which is higher than diesel. The maximum combustion temperature achieved was 869 °C lower than diesel, 891 °C. Lower CO, CO2 and NOx emission during combustion compare to diesel around 34 %, 6% and 90 % reduction respectively. The low combustion temperature, flame length and emission due to the high viscosity of SPO compare to diesel. Fuel spray and flow was affected by viscosity which lowers the combustibility and consumption of SPO. SPO show great properties and combustion performance as fuel for burner system and improvement can make it even better

Splicing system in Automata Theory: A review

The study of formal language theory rapidly evolves after Tom Head introduce his research on formal language theory in 1987. Splicing system involves the process of cutting and pasting on DNA molecules with the presence of restriction enzymes and ligase, respectively. A mathematical model of the splicing system has been developed by using the concept of formal language theory, which is a branch of theoretical computer science and applied discrete mathematics, and informational macromolecules. Over the year, theoretical results in splicing systems have contributed to new research in formal language theory focused on modelling of biochemical processes. In this paper, the relation between formal language theory and some related molecular biological terms are explored. In addition, new ideas in the framework of biomolecular science, for example, the design of automated enzymatic processes are then discussed. Then, a mutual relation that exist in these field is then explained. The regular language can be implemented in the splicing system to show the DFA structure in the splicing system

An Introduction to n-th Order Limit Language

The study of the splicing system swiftly grew after Tom Head investigated the biochemical process modelling involving the DNA in 1987. The process of the splicing system consists of a cut and paste of the DNA molecules. Splicing language produced by the splicing system can be classified into inert, transient, and limit language. Previously, second-order limit language was described as a new set of language from the previous splicing language. In this research, we would like to extend the study to n-th order limit language by investigating the effect of the number of rules involved in the splicing system. Following from here, its properties are explored using the formal language theory

Various regulations on the existence of n-th order limit language

In molecular biology, recombinant Deoxyribonucleic acid technology has ignited an increase in the interest of new researches. Moreover, the splicing system has generated enthusiasm in developing computational models collaborating with formal language theory. Formal language theory tends to be a natural structure for formalising and investigating DNA computing models from this viewpoint. The work of several researchers who added control structures to the splicing formalism, thus creating universal computation systems, has provided additional inspiration for the study of splicing systems. A splicing system is a conventional model of a set of dsDNA that undergoes the cutting and pasting process with the presence of restriction enzyme and ligase. Previously, an introduction of the n-th order limit language is presented and discussed. The properties and the characteristics of the n-th order limit language are developed and also explained by using examples and sort into a few cases. However, the regulation of the existence of the n-th order limit language is left unintended. In this paper, the factors that restrict the formation of the n-th order limit language are discussed. Several restrictions applied are the length of the rules are not equal and same rules applies on several crossing sites of the initial strings. In addition, some examples are given to show the restriction of the formation of n-order limit language

Biomolecular aspects of second order limit language

The study on the recombinant behavior of double-stranded DNA molecules has led to the mathematical modelling of DNA splicing system. The interdisciplinary study is founded from the knowledge of informational macromolecules and formal language theory. A splicing language is resulted from a splicing system. Recently, second order limit language, a type of the splicing language, has been extensively explored. Before this, several types of splicing languages have been experimentally proven. Therefore, in this paper, a laboratory experiment was conducted to validate the existence of a second order limit language. To accomplish it, an initial strand of double-stranded DNA, amplified from bacteriophage lambda, was generated through polymerase chain reaction to generate thousands of copies of double-stranded DNA molecules. A restriction enzyme and ligase were added to the solution to complete the reaction. The reaction mixture was then subjected to polyacrylamide gel electrophoresis to separate biological macromolecules according to their sizes. A mathematical model derived at the early study was used to predict the approximate length of each string in the splicing language. The results obtained from the experiment are then used to verify the mathematical model of a second order limit language. This study shows that the theory on the second order limit language is biologically proven hence the model has been validated

STUDENTS’ PERCEPTIONS OF COMPUTER-BASED LANGUAGE TEST (CBLT) AND VALIDATION OF CBLT-LISTENING QUESTIONNAIRE USING EXPLORATORY FACTOR ANALYSIS

Background and Purpose: One of the difficulties that emerged during online learning was the teaching and learning of listening skills which prompted the development of an online platform, Computer-based Language Test (CBLT), to assist educators conduct listening practices and assessment with students without experiencing geographical limitations. As this is a novel platform, this paper intends to examine students’ perceptions of listening skills and online learning after utilising this platform using the developed CBLT-Listening Questionnaire.   Methodology: This cross-sectional quantitative study employed questionnaires to collect data from diploma students. Two-stage sampling was utilised whereby the first stage used stratified random sampling in selecting classes from twenty-three (23) branches of the university. Simple random sampling was practised in the second stage which yielded 410 responses. The data were subjected to descriptive and exploratory factor analyses (EFA) in SPSS.   Findings: Descriptive analysis revealed that the respondents find listening a difficult skill to acquire yet view CBLT an excellent initiative for online distance learning. EFA revealed that the items in the Listening construct were significant and to be retained. However, the EFA results reported that one item from the Online Distance Learning construct needs to be deleted from the questionnaire.   Contributions: The validated CBLT-S Listening Questionnaire serves as an instrument to investigate the impact of a novel online platform (CBLT) on students' perceptions on listening and online learning. The results from this study evidenced that online platforms that incorporate practices and assessment are viewed positively by students for pedagogy in language teaching.   Keywords: Computer-based language test, exploratory factor analysis, listening skill, online listening test, CBLT-listening questionnaire.   Cite as: Khairuddin, Z., Anuar, N., Azhari, M. A., Serip Mohamad, N. H., Mohd Daud, K., Ahmad, A. R., & Abd Rashid, M. H. (2023). Students’ perceptions of Computer-Based Language Test (CBLT) and validation of CBLT-listening questionnaire using exploratory factor analysis.  Journal of Nusantara Studies, 8(2), 222-241. http://dx.doi.org/10.24200/jonus.vol8iss2pp222-24

On the new relation of second order limit language and other different types of splicing system

Mathematical modelling of splicing system has been introduced to initiate a linkage between the study of informational macromolecules that includes DNA and formal language theory. The ability to present the nitrogenous base which is a component in a nucleotide of DNA, as a series of alphabet, ignites this interdisciplinary study. Over the years, researchers have developed models to match their need. In addition, product of splicing system is called splicing language. Through some development, second order limit language is derived from other type of languages known as limit language. Its existence and characteristics have been vastly discussed. Beside, some types of splicing system can produce second order limit language. In this research, the characteristics of varieties of splicing system are studied and their relations with second order limit language are established

Dynamics of Lebesgue Quadratic Stochastic Operator with Nonnegative Integers Parameters Generated by 2-Partition

The theory of quadratic stochastic operator (QSO) has been significantly developed since it was introduced in 1920s by Bernstein on population genetics. Over the century, many researchers have studied the behavior of such nonlinear operators by considering different classes of QSO on finite and infinite state spaces. However, all these studies do not comprehensively represent the core prob-lem of QSO; i.e., the trajectory behavior. Recently, a class of QSO called Lebesgue QSO has been introduced and studied. Such an operator got its name based on Lebesgue measure which serves as a probability measure of the QSO. The conditions of the Lebesgue QSO have allowed us to con-sider the possibility of introducing a new measure for such QSO. This research presents a new class of Lebesgue QSO with nonnegative integers parameters generated by a measurable 2-partition on the continual state space X=[,]01. This research aims to study the trajectory behavior of the QSO by reducing its infinite variables into a mapping of one-dimensional simplex. The behavior of such operators will be investigated computationally and analytically, where the computational results conform to the analytical results. We will apply measure and probability theory as well as functiona