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The purpose of this paper is to propose and optimize plastic optical fiber (POF) probe with macro-bending biconical tapered structure for the relative humidity (RH) sensing.

In this study, the principle is the evanescent wave power modulated by the ambient humidity. The probe is fabricated by using fused biconical taper and heat-setting method and then coated with a fluorescent moisture-sensitive film.

The probe’s sensing performance can be optimized by changing the probe’s curvature radius, biconical tapered transition length and taper waist diameter. The result shows that the sensitivity of the probe is up to 1.60 and 3.40 mV/ per cent, respectively, at low humidity (10-45 per cent) and high humidity (45-90 per cent). Also, this probe has good linearity, repeatability, photostability and long-term stability.

The proposed probe can improve the sensitivity and linearity of RH sensing without complex devices, which is necessary for mass production, remote measurement and convenient operation.

POF probe with macro-bending biconical tapered structure is investigated in this paper, which is proved to be effective in improving the sensitivity and linearity.

This paper aims to estimate the level of histamine in fish and fish products, as it is very important because of their implication in fish poisoning in humans; hence, ascertaining histamine levels in the aforementioned serves as a chemical index for spoilage.

A technique was developed to immobilize an ordered multilayer of diamine oxidase (DAO) by means of chemical cross-linking on the biconical taper surface stepwisely alternating between chitosan, glutaraldehyde and the enzyme. A spectrophotometric signal results from horseradish peroxidase catalyzed reduction of H₂O₂, a secondary product of the oxidative deamination of histamine monitored at 450 nm.

The biosensor showed a linear response range up to 1.5 mM, a good sensitivity of 0.64 mM-1 with detection and quantification limits towards histamine of 0.086 mM (15.8 ppm) and 0.204 mM (37.7 ppm) and a linear response range of 0-1.5 mM. It showed a response and recovery time of 14 sec and operational stability up to 40 repeated analyses without significant loss of sensitivity.

The developed biosensor has a good potential for use in the quantitative determination of histamine in seafood.

The paper described an outcome of an experimental work on tapered fibre optics (taper)-based biosensor coated with DAO embedded into a chitosan membrane to measure histamine.

The purpose of this paper is to present a review of research performed at the Communications Research Centre Canada on sensing applications of femtosecond infrared laser‐inscribed Bragg gratings.

By using fibre Bragg gratings induced with ultrafast infrared radiation, inscription of high temperature stable sensors in standard and exotic optical waveguides is investigated for a variety of novel applications.

Generally, femtosecond laser‐induced gratings are effective sensors that can be applied in situations and environments where most fibre optic sensors are not effective.

The paper is a review of existing work already published in the literature and provides an overview of this technology to the reader.

The purpose of this study is to present the state of the art for fiber Bragg grating (FBG) acceleration sensing technologies from two aspects: the principle of the measurement dimension and the principle of the sensing configuration. Some commercial sensors have also been introduced and future work in this field has also been discussed. This paper could provide an important reference for the research community.

This review is to present the state of the art for FBG acceleration sensing technologies from two aspects: the principle of the measurement dimension (one-dimension and multi-dimension) and the principle of the sensing configuration (beam type, radial vibration type, axial vibration type and other composite structures).

The current research on developing FBG acceleration sensors is mainly focused on the sensing method, the construction and design of the elastic structure and the design of a new information detection method. This paper hypothesizes that in the future, the following research trends will be strengthened: common single-mode fiber grating of the low cost and high utilization rate; high sensitivity and strength special fiber grating; multi-core fiber grating for measuring single-parameter multi-dimensional information or multi-parameter information; demodulating equipment of low cost, small volume and high sampling frequency.

The principle of the measurement dimension and principle of the sensing configuration for FBG acceleration sensors have been introduced, which could provide an important reference for the research community.

The main purpose of this study is to demonstrate the development of an enzyme-based sensor for haloalkane detection. Haloalkane is a toxic compound that is found as genotoxic impurities in pharmaceutical products and contaminants in waste. The need to investigate the genotoxic level in pharmaceutical manufacturing is very crucial because of its toxicity effects on human health. The potential of mini protein as an alternative bioreceptor was explored with the aim to be more effective and stable under extreme conditions.

Mini proteins of haloalkane dehalogenase (HLD) were computationally designed and experimentally validated. Tapered multimode fiber (TMMF) was bio-functionalized with a bioreceptor either native (positive control) or mini protein. The absorbance-based sensor resulting from the binding interaction of mini protein with haloalkane was monitored through a wavelength range of 200-1,300 nm.

An increment of the UV absorption is observed at 325 nm when haloalkane interacted with the immobilized bioreceptors, native or mini protein. Both biosensors displayed a continuous response over the range of 5-250 µM haloalkane. They also had the capability to detect haloalkanes below 1 min and with an operational stability of up to seven days without significant loss of sensitivity.

The results indicate the potential viability of the enzyme HLD-based sensor to monitor the existence of haloalkane in both pharmaceutical and environmental products.

The paper describes an outcome of experimental work on TMMF-based biosensor coated with HLD for label-free haloalkane detection. Mini protein can be used as an effective bioreceptor with some structural modification to improve functionality and stability.

Two disastrous Tsunamis, one on the west coast of Sumatra Island, Indonesia, in 2004 and another in North East Japan in 2011, had seriously destroyed a large number of bridges. Thus, experimental tests in a wave flume and a fluid structure interaction (FSI) analysis were constructed to gain insight into tsunami bore force on coastal bridges.

Various wave heights and shallow water were used in the experiments and computational process. A 1:40 scaled concrete bridge model was placed in mild beach profile similar to a 24 × 1.5 × 2 m wave flume for the experimental investigation. An Arbitrary Lagrange Euler formulation for the propagation of tsunami solitary and bore waves by an FSI package of LS-DYNA on high-performance computing system was used to evaluate the experimental results.

The excellent agreement between experiments and computational simulation is shown in results. The results showed that the fully coupled FSI models could capture the tsunami wave force accurately for all ranges of wave heights and shallow depths. The effects of the overturning moment, horizontal, uplift and impact forces on a pier and deck of the bridge were evaluated in this research.

Photos and videos captured during the Indian Ocean tsunami in 2004 and the 2011 Japan tsunami showed solitary tsunami waves breaking offshore, along with an extremely turbulent tsunami-induced bore propagating toward shore with significantly higher velocity. Consequently, the outcomes of this current experimental and numerical study are highly relevant to the evaluation of tsunami bore forces on the coastal, over sea or river bridges. These experiments assessed tsunami wave forces on deck pier showing the complete response of the coastal bridge over water.

To provide a good insight into solving a multi‐response optimization problem using neuro‐fuzzy model and Taguchi method of experimental design.

Over the last few years in many manufacturing organizations, multiple response optimization problems were resolved using the past experience and engineering judgment, which leads to increase in uncertainty during the decision‐making process. In this paper, a four‐step procedure is proposed to resolve the parameter design problem involving multiple responses. This approach employs the advantage of both artificial intelligence tool (neuro‐fuzzy model) and Taguchi method of experimental design to tackle problems involving multiple responses optimization.

The proposed methodology is validated by revisiting a case study to optimize the three responses for a double‐sided surface mount technology of an electronic assembly. Multiple signal‐to‐noise ratios are mapped into a single performance statistic through neuro‐fuzzy based model, to identify the optimal level settings for each parameter. Analysis of variance is finally performed to identify parameters significant to the process.

The proposed model will be validated in future by conducting a real life case study, where multiple responses need to be optimized simultaneously.

It is believed that the proposed procedure in this study can resolve a complex parameter design problem with multiple responses. It can be applied to those areas where there are large data sets and a number of responses are to be optimized simultaneously. In addition, the proposed procedure is relatively simple and can be implemented easily by using ready‐made neural and statistical software like Neuro Work II professional and Minitab.

This study adds to the literature of multi‐optimization problem, where a combination of the neuro‐fuzzy model and Taguchi method is utilized hand‐in‐hand.