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Article
Publication date: 19 June 2017

Yoshiteru Amemiya and Shin Yokoyama

This paper aims to develop ring resonator type optical sensors for high-sensitive detection of biomaterials and a solution concentration surrounding sensor devices. The…

Abstract

Purpose

This paper aims to develop ring resonator type optical sensors for high-sensitive detection of biomaterials and a solution concentration surrounding sensor devices. The sensing characteristics of a proposed device are investigated.

Design/methodology/approach

The proposed device structure is multi-slot ring resonator where the horizontal slots are arranged in vertical direction called as stacked multi-slot ring resonator. The ring resonator consists of silicon nitride because of several advantages such as easy integration of Si photo-detectors. A high sensitivity is expected in this structure because the slot height is precisely controlled by the thickness of stacked silicon nitride and etched silicon oxide layers. Sensing characteristics are evaluated from the simulated effective refractive index using the finite element method and sucrose solution sensing is confirmed using polydimethylsiloxane fluid channel.

Findings

In the simulation for the solution concentration sensor, the detection sensitivity is enhanced with increasing the slot height and the number of slots. On the other hand, for the biomaterial sensor such as the adsorbed antigen-antibody reaction, the sensitivity increases with decreasing the slot height. In this case, more than four times higher sensitivity is expected compared with the slot ring resonator sensor with vertical single slot and 0.1-0.2 μm slot width.

Originality/value

This paper presents an improved new structure of ring resonator type sensors and its optimum design parameters. The sensing characteristics are evaluated, and, for the biomaterial sensor, the sensitivity is high in comparison to the previous slot ring resonator.

Article
Publication date: 17 May 2013

Abdullah M. Asiri, Khalid A. Alamry and Mahmoud A. Hussein

The purpose of this paper is to investigate the effect of annealing on photochromic performance of (E)‐dicyclopropylmethylene‐(2…

Abstract

Purpose

The purpose of this paper is to investigate the effect of annealing on photochromic performance of (E)‐dicyclopropylmethylene‐(2, 5‐dimethyl‐3‐furylethylid‐ene)‐succinicanhydride doped in polyacrylic acid thin film.

Design/methodology/approach

(E)‐dicyclopropylmethylene‐(2,5‐dimethyl‐3‐furyl‐ethylidene)‐succinic‐anhydride (DMDFS‐E) fulgide doped in polyacrylic acid thin films was prepared. DMDFS‐E fulgide doped in polyacrylic acid thin films was heated at various annealing temperatures. Photocoloration, photobleaching and photochemical fatigue resistance for the desired DMDFS‐E fulgide doped in polyacrylic acid thin films were studied.

Findings

Upon irradiation with UV light (366 nm), fulgide DMDFS‐E undergoes a conrotatory ring closure to the pinkish colored closed form C (523 nm). The later color was switched back to the original color when the films were irradiated with white light. The kinetics of photocoloration and photobleaching processes were followed spectrophotometrically by monitoring the absorbance of the ring closed product DMDFS‐C at its λmax of 523 nm. The first‐order plots of photocoloration reaction showed distinct linear line at different temperatures. The slope of these first‐order lines corresponding to the rate constants k. It was found that for photocoloration reaction, the rate constant of the photocoloration reaction was slower than the photobleaching reaction and both reactions decrease with increasing the annealing temperatures. It was found that there was almost improvement of photochemical fatigue resistance of fulgide DMDFS‐E doped in polyacrylic acid thin film at several of the annealing temperatures.

Originality/value

The results obtained in this work showed that the photochromic properties of DMDFS fulgide E were improved upon annealing the film at 100°C. Therefore, it would be recommended for improvement to apply fulgides as annealed polymer films.

Details

Pigment & Resin Technology, vol. 42 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 20 April 2022

Hieu Thi Ngo, Le Duc Niem, Phong Cong Tran, Truc Thanh Nguyen, Dung Thi Doan and Huyen Thi Ngo

This paper aims at identifying perceived factors and measuring opinions about the factors' impact on academic staff development (ASD) at Tay Nguyen University (TNU), Dak…

Abstract

Purpose

This paper aims at identifying perceived factors and measuring opinions about the factors' impact on academic staff development (ASD) at Tay Nguyen University (TNU), Dak Lak, Vietnam.

Design/methodology/approach

The research used the exploratory factor analysis (EFA) method, the multiple regression model (ordinary least squares (OLS)) and a five-point Likert scale questionnaire. A sample of 70 managerial staff, 374 lecturers and 512 students of TNU was surveyed to obtain data.

Findings

The EFA showed that opinions concerning university autonomy (UA) and university social responsibility (USR) were positively correlated. With the above two factors united as responsible autonomy (RA), the OLS indicated perceptions that RA and internal driving factor (IF) had significant and positive impacts on the ASD, while external driving factor (EF) was found to have a perceived negative influence on ASD.

Research limitations/implications

The results indicated that there appears to be a close relationship between UA and USR, and these can be considered as a factor that has apparent impacts on the ASD of the university.

Practical implications

The degree of UA and USR of TNU should be enhanced through awareness of the university's academic staff, the application of a suitable evaluation system and the efficiency of university's regulations. In addition, efforts should be made to improve internal factors such as the dissemination of educational philosophy, the suitability of strategic plans, the development of key performance indicators KPIs and the building of organizational culture – all of which will help to heighten the university’s ASD. At the same time, TNU should endeavor to quickly transform aspects of administration and management to meet the shifting requirements of the autonomous environment and competitive features of the market economy. In particular, there is a need for the academic staff themselves to have increased capacity to adapt to these changes.

Social implications

The authors' results have a broader application to not only the case of TNU but to other situations in developing countries where universities are in transitional stages as governments assign increasing autonomy and responsibility to them.

Originality/value

This paper suggests that the academic staff of TNU should be provided with both professional autonomy and adaptive capacity to foster research and educational innovation in the market-based higher education system of Vietnam. More generally, if true, the paper suggests that an increase in the degree of UA and USR should be combined with the efforts to improve the internal environments such as disseminating educational philosophy, mission, vision and strategies and building organizational culture.

Details

Journal of Applied Research in Higher Education, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2050-7003

Keywords

Article
Publication date: 6 November 2009

A.A. Bahajaj, A.M. Asiri, A.M. Alsoliemy and A.G. Al‐Sehemi

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

Abstract

Purpose

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

Design/methodology/approach

The poly(methyl methacrylate) PMMA and epoxy resin doped with photochromic spirooxazine (SO) are prepared and the effects of ultraviolet (UV) irradiation are studied using spectrophotometer. The reversible reaction is effected using white light. Photochemical fatigue resistance of these films is also studied.

Findings

Irradiation of colourless 7′,8′‐dichloro‐1,3,3‐trimethylspiro[indoline‐2,3′‐[3H]benzo[b][1,4]oxazine] (SO) doped in PMMA and epoxy resin with UV light (366 nm) results in the formation of an intense purple‐red coloured zwitterionic photomerocyanine (PMC). The reverse reaction is photochemically induced by irradiation with white light. Photocolouration and photobleaching reactions follow a first‐order rate equation. It is found that photocoloration rate constant of (SO) in both matrices is almost the same, which is unexpected. On the other hand, the rate of photobleaching reaction of (PMC) in PMMA is twice slower than that in the epoxy resin. It seems that the presence of the two chlorine atoms at positions 7′ and 8′ of the benzooxazine moiety destabilise the PMC in epoxy resin film and results in speeding up the fading process compared to that in PMMA. SO doped in epoxy resin shows much better fatigue resistance than that doped in PMMA.

Research limitations/implications

The PMMA and epoxy resin polymers doped photochromic spirobenzooxazine described in this paper were prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

Practical implications

The photochromic materials developed can be used for different applications, such as coatings and holography.

Originality/value

The method developed may be used to enhance the performance of photochromic materials.

Details

Pigment & Resin Technology, vol. 38 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 15 November 2011

Rémy Magnier‐Watanabe

In an economy where firms compete for limited resources, focusing internally to boost efficiency and reduce waste is critical. In particular, the kaizen philosophy of

4980

Abstract

Purpose

In an economy where firms compete for limited resources, focusing internally to boost efficiency and reduce waste is critical. In particular, the kaizen philosophy of continuous improvement in small sustainable increments has spread in the manufacturing industry with mixed results. However, the knowledge management requirements of kaizen have not yet been formalized for practitioners to easily check the necessary pre‐conditions of their organization. The objective of this paper is to explore the successful implementation of kaizen in terms of its organizational design and knowledge management preconditions.

Design/methodology/approach

Using a case‐study approach building on previous in‐depth research of New United Motor Manufacturing Inc. (NUMMI) in Fremont, California, this study assesses the organizational and knowledge preconditions of kaizen.

Findings

The results show that the success of NUMMI may reside as much in Toyota's production system as in the alignment of kaizen and the organizational characteristics that support suitable knowledge management practices.

Practical implications

The findings highlight the need for practitioners who plan to implement kaizen to review their firm's organizational characteristics and knowledge management practices and ensure their congruence with the requirements of kaizen.

Originality/value

The paper shows how kaizen cannot be reduced to an add‐on grafted onto existing processes and aimed at temporarily fixing the bottom line. Instead, kaizen is deeply rooted in, and therefore strongly dependent on, the processes it intends to improve.

Details

VINE, vol. 41 no. 4
Type: Research Article
ISSN: 0305-5728

Keywords

Article
Publication date: 1 June 1997

Jaroslav Mackerle

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the…

5518

Abstract

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

Details

Engineering Computations, vol. 14 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 23 March 2010

A.A. Bahajaj, A.M. Asiri, A.M. Alsoliemy and A.G. Al‐Sehemi

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

Abstract

Purpose

The purpose of this paper is to evaluate the photochromic performance of photochromic compounds in polymer matrices.

Design/methodology/approach

The poly(methyl methacrylate) (PMMA) and epoxy resin doped with photochromic spirobenzopyran were prepared and the effects of ultraviolet (UV) irradiation were studied using spectrophotometer. The reversible reaction was effected using white light. Photochemical fatigue resistance of these films was also studied.

Findings

Irradiation of colourless 1′,3′,3′‐trimethyl‐6‐nitrospiro[2H‐1‐benzopyran‐2,2′‐indoline] spiropyran (SP) doped in PMMA and epoxy resin with UV light (366 nm) results in the formation of an intense purple‐red coloured zwitterionic photomerocyanine (PMC). The reverse reaction was photochemically induced by irradiation with white light. Photocolouration of SP doped in PMMA follows a first‐order rate equation (k=0.0011 s−1), while that doped in epoxy resin deviates from linearity. It was found that photobleaching follows a first‐order equation in both matrices. The photobleaching rate constant of PMC in both matrices is the same and equals 0.0043 s−1. Spirobenzopyran doped in PMMA shows better fatigue resistance than that doped in epoxy resin.

Research limitations/implications

The PMMA and epoxy resin polymers doped with photochromic spirobenzopyran described in the present paper were prepared and studied. The principle of study established can be applied to any type of polymer or to any type of photochromic compounds.

Practical implications

The photochromic materials developed can be used for different applications, such as coatings and holography.

Originality/value

The method developed may be used to enhance the performance of photochromic materials.

Details

Pigment & Resin Technology, vol. 39 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 12 April 2022

Hildemar Dos Santos, Diane Han, Mayabel Perez, Summer Johnson and Razaz Shaheen

To gain a better and more comprehensive understanding, this study aims to investigate the literature to explore the two popular diets’ health benefits and concerns. Google…

Abstract

Purpose

To gain a better and more comprehensive understanding, this study aims to investigate the literature to explore the two popular diets’ health benefits and concerns. Google Scholar and PubMed were used to search for available and relevant nutrition and health articles that pertain to the benefits and concerns of plantogenic and ketogenic diets. Search terms like low carbohydrate, diet, ketogenic, vegetarian and chronic diseases were used. Information was obtained from review articles and original research articles and checked for accuracy. Ketogenic diets have been used for a long time for convulsion in children and now reappeared for weight loss purposes.

Design/methodology/approach

Ketogenic and plantogenic (plant-based) diets have been adopted today by many professionals and the public.

Findings

Ketogenic diets have been used for a long time for convulsion in children and now reappeared for weight loss purposes. Plantogenic diets also have been practiced for many years for religious, health and environmental reasons. Compared to plantogenic diets, ketogenic diets lack long-term evidence of its potential benefits and harm.

Research limitations/implications

Maybe Lacto-ovo vegetarian and pesco-vegetarian (eat fish but not meats) diets are OK. However, for strict plantogenic diets (total plantogenic/vegan diet), the risk of mineral or vitamin deficiency is present (Melina et al., 2016). Of particular concern is dietary vitamin B12, which is obtained mostly from animal sources (Melina et al., 2016). A long-term deficiency of vitamin B12 can lead to macrocytic anemia and cause neuro and psychological effects (Obeid et al., 2019). Also, omega-3 fatty acids may be deficient in such a diet and probably need to be supplemented on those who follow the total plantogenic diet (Melina et al., 2016). Other deficiencies of concern would be zinc, iron, calcium, vitamin D and iodine (Melina et al., 2016). Another disadvantage is that many junk foods could be easily classified within the plantogenic diet, such as sugar, cakes, French fries, white bread and rice, sugar-sweetened beverages and sweets in general. These items are related to higher weight gain and, consequently, to a higher incidence of diabetes and other chronic diseases (Schulze et al., 2004; Malik et al., 2006; Fung et al., 2009).

Originality/value

Plantogenic diets were concluded to have sustainable health benefits for humans and the environment over ketogenic diets, which could be used but under professional follow-up only.

Details

Nutrition & Food Science , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 6 September 2022

Rajan Kumar Gangadhari, Vivek Khanzode, Shankar Murthy and Denis Dennehy

This paper aims to identify, prioritise and explore the relationships between the various barriers that are hindering the machine learning (ML) adaptation for analysing…

Abstract

Purpose

This paper aims to identify, prioritise and explore the relationships between the various barriers that are hindering the machine learning (ML) adaptation for analysing accident data information in the Indian petroleum industry.

Design/methodology/approach

The preferred reporting items for systematic reviews and meta-analysis (PRISMA) is initially used to identify key barriers as reported in extant literature. The decision-making trial and evaluation laboratory (DEMATEL) technique is then used to discover the interrelationships between the barriers, which are then prioritised, based on three criteria (time, cost and relative importance) using complex proportional assessment (COPRAS) and multi-objective optimisation method by ratio analysis (MOORA). The Delphi method is used to obtain and analyse data from 10 petroleum experts who work at various petroleum facilities in India.

Findings

The findings provide practical insights for management and accident data analysts to use ML techniques when analysing large amounts of data. The analysis of barriers will help organisations focus resources on the most significant obstacles to overcome barriers to adopt ML as the primary tool for accident data analysis, which can save time, money and enable the exploration of valuable insights from the data.

Originality/value

This is the first study to use a hybrid three-phase methodology and consult with domain experts in the petroleum industry to rank and analyse the relationship between these barriers.

Details

Benchmarking: An International Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1463-5771

Keywords

Article
Publication date: 17 August 2021

Edward Shih-Tse Wang and Fang-Tzu Hu

For Internet celebrities, self-disclosure (SD) is a crucial step in building relationships with their followers who perceive this communication as para-social interaction…

Abstract

Purpose

For Internet celebrities, self-disclosure (SD) is a crucial step in building relationships with their followers who perceive this communication as para-social interaction (PSI), which facilitates socialization among followers. Normative commitment (NC) is critical for creating bonds among community members that are strengthened through socialization. However, research on the predictive relationships among SD, PSI and NC has been insufficient. This paper aims to investigate the effects of two facets of Internet celebrity SDs (i.e. private life and opinion) and two facets of PSI (i.e. companionship and following) on NC. The mediating role of PSI on the effects of SD on NC was also analyzed.

Design/methodology/approach

People who follow at least one Internet celebrity on a social networking site were recruited to participate in this study, and 494 valid questionnaires were collected for examination. The collected data were analyzed using structural equation modeling (SEM).

Findings

The results revealed that both private-life and opinion SDs have positive effects on companionship and following PSI, which consequently influence NC. A mediation test revealed that companionship and following PSI mediate the effects of private-life and opinion SD on NC. This study's findings also revealed that NC is influenced more by following PSI than it is by companionship PSI. Furthermore, opinion SD was determined to be the more influential factor in following PSI, whereas private-life SD was the more influential factor in companionship PSI.

Originality/value

This paper is useful for understanding the influence mechanism of the SD of Internet celebrities on PSI and NC.

Details

Journal of Research in Interactive Marketing, vol. 16 no. 2
Type: Research Article
ISSN: 2040-7122

Keywords

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