Dynamics of absorption properties of CDOM and its composition in Likas estuary, North Borneo, Malaysia

This is the final version. Available from Elsevier via the DOI in this record. Chromophoric Dissolved Organic Matter (CDOM) is a vital water constituent in aquatic ecosystems that contributes to water colour, affects light penetration, and impacts primary production. This study aims to determine the spatial and monsoonal variability of CDOM absorption properties in the Likas estuary, characterise the source of CDOM, and investigate the correlations between CDOM absorption properties and salinity. Likas estuary is a small estuary located in Kota Kinabalu city on the west coast of Sabah, facing the South China Sea. A mangrove ecosystem surrounds it with manufactured structures such as residential areas and public facilities. Surface water samples were collected at 19 stations: upstream of rivers to the river mouth and coastal area during spring tides every month, from June 2018 to July 2019, for 14-months. The distribution of aCDOM(440) in the study area is predictable as a signature in a coastal area with a decreasing gradient from the upstream towards coastal water (0.29 ± 0.19 m−1 to 1.05 ± 0.39 m−1). There are increasing spatial patterns of spectral slopes S275-295 and SR. However, S350-400 and S300-600 declined spatial gradients from the upstream to coastal water. Thus, S300-600 indicates a linear relationship between aCDOM(440), which unconventional results in coastal water. We suspect this is due to a small coverage of the study site with a distance of 0.5 m intervals of each station. This could be why the S300-600 had constant values throughout the study area (with no statistical difference between stations). In addition, S300-600 was merely varied in the stations located at the river mouth and coastal water. Based on the spectral slope ratio (SR), most of the stations located in the Darau, Inanam, and Bangka-Bangka rivers had SR values less than 1. Hence, CDOM in these stations is a terrestrial-dominated source. Therefore, from our observations during the study period, monsoonal variation could alter the source of CDOM in the study area.Universiti Malaysia SabahUniversiti Malaysia SabahMinistry of Higher Education of Malaysi

Development of a cutting edge temperature measurement of end mill tool by using infrared radiation technique

This paper describes the development of cutting temperature measurement of end mill tool by using infrared radiation technique approach. Compared to conventional thermocouple technique, infrared radiation technique is an advance method of measuring temperature which featured high accuracy, high response rate, wide range of temperature scale detection and almost compatible with all materials used in the manufacturing industry. We measures the emission of infrared radiation from the source, which is cutting edge of tool by using photocells that contains InAs and InSb photovoltaic detectors. Photocells converts the infrared radiation to a voltage signal and then recorded by oscilloscope followed with a calibration with its corresponding temperature. This paper discussed about the calibration method, cutting experiment setup, the limit of infrared radiation level detected by photocells, signal correction of output signal, and relations of peak signal formation with rotation of end mill tool. The developed pyrometer is also capable to profile the cutting tool’s rotation based on the movements of infrared radiation’s emission at cutting tool’s edge. The conclusion was that the measurement of cutting temperature of high speed machining by using infrared radiation technique is possible. The developed pyrometer are capable to detect temperature changes at a span of 0.01 ms

Determination of trace metals in airborne particulate matter of Kuala Terengganu, Malaysia

Results from the present study in Kuala Terengganu, Malaysia indicated a significant spatial variation but generally the total suspended particulate concentrations (mean = 17.2–148 lg/m3) recorded were below the recommended Malaysia guideline for total suspended particulate (mean of 24-h measurement = 260 lg/m3). Some of the elemental composition of particulate aerosol is clearly affected by non crustal sources, e.g. vehicular emission sources. Based on correlation and enrichment analyses, the elements could be grouped into two i.e. Pb, Cd and Zn group with sources from vehicular emission (r[0.6; enrichment factor[10) and Al, Fe, Mn and Cr group that appears to be of crustal origin (r[0.6; enrichment factor\10). It can also be concluded that the mean levels of Pb (1 ng/m3), Cd (0.02 ng/m3) and Zn (2 ng/m3) in the study area are generallylower than other urban areas in Malaysia (Pb\181 ng/m3; Cd\6 ng/m3; Zn\192 ng/m3)

Assessing bat roosts using the LiDAR system at Wind Cave Nature Reserve in Sarawak, Malaysian Borneo

Conventionally, bat roost counts and roost size estimation are potentially a disruptive, repetitive method and are time consuming. Introduction of the Light Detection and Ranging (LiDAR) scanning system, an optical remote sensing technology, for scientific purposes have open many research possibilities especially on cave wildlife surveys. Scanned images at high resolution provide new effective biological tools for assessing bat roosts inside caves on walls or ceiling in total darkness. LiDAR system was applied to census bats that roost in Wind Cave Nature Reserve, Sarawak, Malaysia, based on laser return intensity values from the images. Bats that roost in large clusters, specifically Penthetor lucasi were determined through automated counting using connected components labelling, a graph theory algorithm mostly used in image analysis applications. Roost surface area of bats species was calculated based on point clouds extracted and using simple trigonometry. Wind Cave was successfully modelled into three dimensional (3D) cave images with bats roosting inside the cave. The roost sites of bats in the cave were represented in coloured point clouds that represent the species. Through LiDAR images, bats in Wind Cave consisted of about 979 individuals of P. lucasi and 1,907 individuals of insectivorous bats from nine species representing four families. There is a positive correlation between group size and roost area. For every additional bat, roost area is expected to increase by an average of 1.75 m2. Our result suggested that terrestrial LiDAR technology is capable of assessing bat roosts in their natural habitat to determine their roost size and number of individuals that roost in the cave. Terrestrial LiDAR application is most complementary when integrated with field surveys to produce more reliable outcomes which open up possibilities of effective conservation action plans

Current Directions and Future Research Priorities of Customer Data Analysis

Customer analysis is receiving special attention from both researchers and professionals. The objective of this paper is to identify the trends of techniques used to address customer's current problems and shed light on future research directions using a literature review. We reviewed the literature for the last five years. The findings revealed that customer purchase was the most popular technique used by the research community followed by customer satisfaction and visit wit. Whereas customer segmentation and customer churn were the least. However, the regression method was commonly used for predicting customer purchase and behavior. But, social media and big data are still in their early stages for customer analytics research