Temperature and Path Length Optimisation for near Infrared Measurement of Liquid Samples: An Alternative Approach

2007 ◽  
Vol 15 (2) ◽  
pp. 71-80 ◽  
Author(s):  
M.J. Sáiz-Abajo ◽  
J.M. González-Sáiz ◽  
C. Pizarro

Traditionally, when performing a spectroscopic measurement, temperature and path length are normally set by modifying one factor at a time. This fact means that spectroscopists can be unaware of some possible interaction between these factors and it supposes that a lot of experimental effort is required before inexperienced researchers understand the extent of the variation these may introduce. In this study, experimental design methodology and the subsequent evaluation of results were proposed and applied to this problem in order to make the selection of conditions easier and ensure that it is performed correctly. The present paper is a case study which focused on the selection of path length and temperature for near infrared measurements of vinegar samples from different origins. The main objective was to ensure repeatability between replicates and to make sure that absorbance values in the spectra fell within the linear absorbance range of 0.5–2 au. This paper reports the detection of possible interactions between the factors which can lead to erroneous interpretation of results.

1995 ◽  
Vol 83 (4) ◽  
pp. 738-746. ◽  
Author(s):  
Warren J. Levy ◽  
Serle Levin ◽  
Britton Chance

Background The application of phase-modulated near-infrared techniques for measurement of the oxygen saturation of cerebral tissue requires both validation by conventional measures of cerebral oxygenation and determination of normal and abnormal values. This study was undertaken to validate phase-modulated near-infrared measurements of cerebral oxygen saturation by comparing them with electroencephalographic evidence of cerebral ischemia during implantation of cardioverting defibrillators. This comparison also yields an estimate of the ischemic threshold as measured with near-infrared techniques. Methods Electroencephalograms and near-infrared measurements were performed during 85 episodes of ventricular fibrillation in ten patients. Light at 754, 785, and 816 nm was modulated at 200 MHz, transmitted through the skull, and the path lengths of the reflected light were determined by measuring the phase shifts. The electroencephalogram was inspected for changes during the hypotension associated with the arrhythmia and the oxygen saturation was calculated from the near-infrared path lengths. Changes in oxygen saturation were then compared with electroencephalographic evidence of cerebral ischemia. Results The mean saturation before fibrillation was 56.5% +/- 1.2 (SEM). In 40 (47%) of the events, electroencephalographic evidence of ischemia was observed. Such changes were related to the minimum saturation observed during ventricular fibrillation (44% +/- 2.5 vs. 56% +/- 1.9 in the absence of electroencephalographic changes; P < 0.001). The ischemic threshold was estimated to be 47% saturation. The sensitivity of this technique was estimated to be 0.6, the specificity 0.84, and the predictive accuracy 0.73. Conclusions Near-infrared measurements reflect changes in cerebral oxygenation as indicated by electroencephalographic evidence of cerebral ischemia.


Sains Insani ◽  
2018 ◽  
Vol 3 (2) ◽  
pp. 15-21
Author(s):  
Zulkefli Aini ◽  
Abdul Ghafar Don ◽  
Ahmad Irdha Mokhtar ◽  
Nur Uswah Ahmad Fauzi

One of the factors that can affect a person's behavior is a communication message. In the context of the da`wah, preachers who involved actively in da`wah communication with the Orang Asli should be able to ensure that the message conveyed can be understood by the target group. In addition, the selection of the correct messages of da`wah based on the foremost priority simplify the process of sharing information between the preachers and the Orang Asli. Accordingly, this article aims to identify specific topics of Islamic faith (akidah) submitted by the Orang Asli in the process of da`wah communication and to identify verbal feedback given by the preachers to the Orang Asli of the topics. This qualitative study using case study design and data was collected through semi-structured interviews. Interviews involving nine preachers were active in da`wah activity to the Orang Asli community in Selangor. Data were analyzed thematically according to the specified objectives. The study found that the topics frequently raised by the Orang Asli is concerned about belief in Allah, belief in Malaikat, and belief in Qada' and Qadar. The topics may be found within the framework of worldview in their beliefs and practice of ancient traditions. Therefore, the preachers gave verbal feedback on these topics is based on a clear and precise sample corresponding to the level of their thinking. The emphasis on these topics is very important to strengthen and purify the faith of the community.Keywords: Communication; Message; Preacher; Indigenous community Abstrak: Elemen mesej dalam komunikasi merupakan salah satu faktor yang dapat memberi kesan terhadap perubahan tingkah laku seseorang. Dalam konteks dakwah, pendakwah yang terlibat dalam proses komunikasi dakwah dengan Orang Asli seharusnya berkebolehan memastikan kandungan mesej yang disampaikan boleh difahami oleh sasaran dakwahnya. Di samping itu, pemilihan mesej dakwah yang betul mengikut keutamaan memudahkan proses perkongsian maklumat antara pendakwah dengan Orang Asli. Sehubungan dengan itu, artikel ini bertujuan untuk mengenalpasti topik-topik tertentu dalam mesej akidah yang dikemukakan oleh masyarakat Orang Asli kepada pendakwah dan mengenalpasti maklum balas lisan yang diberikan oleh pendakwah kepada Orang Asli terhadap topik tersebut. Kajian kualitatif ini menggunakan reka bentuk kajian kes dengan pengumpulan data melalui temu bual separa struktur. Temu bual melibatkan sembilan orang pendakwah yang aktif dalam aktiviti dakwah masyarakat Orang Asli di Selangor. Data kajian dianalisis secara tematik mengikut objektif yang ditentukan. Kajian ini mendapati bahawa topik-topik yang sering dikemukan oleh Orang Asli kepada pendakwah dalam penyampaian mesej akidah ialah berkenaan tentang keimanan kepada Allah SWT, keimanan kepada malaikat, dan keimanan kepada qada’ dan qadar. Topik-topik berkenaan didapati berada dalam kerangka worldview kepercayaan dan amalan tradisi mereka. Sehubungan dengan itu, pendakwah memberikan maklum balas lisan terhadap topik-topik tersebut adalah berdasarkan keterangan yang jelas dan contoh yang tepat bersesuaian dengan tahap pemikiran mereka. Penekanan terhadap topik-topik tersebut merupakan perkara yang penting dalam rangka mengukuhkan dan memurnikan akidah masyarakat Orang Asli.Kata kunci: Komunikasi; Mesej; Pendakwah; Komuniti Orang Asli


2019 ◽  
Vol 73 (3) ◽  
pp. 218-221
Author(s):  
Kihachiro Bannno
Keyword(s):  

2013 ◽  
Vol 5 (2) ◽  
pp. 48-53
Author(s):  
William Aprilius ◽  
Lorentzo Augustino ◽  
Ong Yeremia M. H.

University Course Timetabling Problem is a problem faced by every university, one of which is Universitas Multimedia Nusantara. Timetabling process is done by allocating time and space so that the whole associated class and course can be implemented. In this paper, the problem will be solved by using MAX-MIN Ant System Algorithm. This algorithm is an alternative approach to ant colony optimization. This algorithm uses two tables of pheromones as stigmergy, i.e. timeslot pheromone table and room pheromone table. In addition, the selection of timeslot and room is done by using the standard deviation of the value of pheromones. Testing is carried out by using 105 events, 45 timeslots, and 3 types of categories based on the number of rooms provided, i.e. large, medium, and small. In each category, testing is performed 5 times and for each testing, the data recorded is the unplace and Soft Constraint Penalty. In general, the greater the number of rooms, the smaller the unplace. Index Terms—ant colony optimization, max-min ant system, timetabling


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Simone Savoia ◽  
Andrea Albera ◽  
Alberto Brugiapaglia ◽  
Liliana Di Stasio ◽  
Alessio Cecchinato ◽  
...  

Abstract Background The possibility of assessing meat quality traits over the meat chain is strongly limited, especially in the context of selective breeding which requires a large number of phenotypes. The main objective of this study was to investigate the suitability of portable infrared spectrometers for phenotyping beef cattle aiming to genetically improving the quality of their meat. Meat quality traits (pH, color, water holding capacity, tenderness) were appraised on rib eye muscle samples of 1,327 Piemontese young bulls using traditional (i.e., reference/gold standard) laboratory analyses; the same traits were also predicted from spectra acquired at the abattoir on the intact muscle surface of the same animals 1 d after slaughtering. Genetic parameters were estimated for both laboratory measures of meat quality traits and their spectra-based predictions. Results The prediction performances of the calibration equations, assessed through external validation, were satisfactory for color traits (R2 from 0.52 to 0.80), low for pH and purge losses (R2 around 0.30), and very poor for cooking losses and tenderness (R2 below 0.20). Except for lightness and purge losses, the heritability estimates of most of the predicted traits were lower than those of the measured traits while the genetic correlations between measured and predicted traits were high (average value 0.81). Conclusions Results showed that NIRS predictions of color traits, pH, and purge losses could be used as indicator traits for the indirect genetic selection of the reference quality phenotypes. Results for cooking losses were less effective, while the NIR predictions of tenderness were affected by a relatively high uncertainty of estimate. Overall, genetic selection of some meat quality traits, whose direct phenotyping is difficult, can benefit of the application of infrared spectrometers technology.


2021 ◽  
Vol 13 (6) ◽  
pp. 3571
Author(s):  
Bogusz Wiśnicki ◽  
Dorota Dybkowska-Stefek ◽  
Justyna Relisko-Rybak ◽  
Łukasz Kolanda

The paper responds to research problems related to the implementation of large-scale investment projects in waterways in Europe. As part of design and construction works, it is necessary to indicate river ports that play a major role within the European transport network as intermodal nodes. This entails a number of challenges, the cardinal one being the optimal selection of port locations, taking into account the new transport, economic, and geopolitical situation that will be brought about by modernized waterways. The aim of the paper was to present an original methodology for determining port locations for modernized waterways based on non-cost criteria, as an extended multicriteria decision-making method (MCDM) and employing GIS (Geographic Information System)-based tools for spatial analysis. The methodology was designed to be applicable to the varying conditions of a river’s hydroengineering structures (free-flowing river, canalized river, and canals) and adjustable to the requirements posed by intermodal supply chains. The method was applied to study the Odra River Waterway, which allowed the formulation of recommendations regarding the application of the method in the case of different river sections at every stage of the research process.


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