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Real-Time Medical Systems Based on Human Biometric Steganography: a Systematic Review

Mohsin AH, Zaidan AA, Zaidan BB, Ariffin SAB, Albahri OS, Albahri AS, et al.

J Med Syst, 2018 Oct 29;42(12):245.
PMID: 30374820 DOI: 10.1007/s10916-018-1103-6

In real-time medical systems, the role of biometric technology is significant in authentication systems because it is used in verifying the identity of people through their biometric features. The biometric technology provides crucial properties for biometric features that can support the process of personal identification. The storage of biometric template within a central database makes it vulnerable to attack which can also occur during data transmission. Therefore, an alternative mechanism of protection becomes important to develop. On this basis, this study focuses on providing a detailed analysis of the extant literature (2013-2018) to identify the taxonomy and research distribution. Furthermore, this study also seeks to ascertain the challenges and motivations associated with biometric steganography in real-time medical systems to provide recommendations that can enhance the efficient use of real-time medical systems in biometric steganography and its applications. A review of articles on human biometric steganography in real-time medical systems obtained from three main databases (IEEE Xplore, ScienceDirect and Web of Science) is conducted according to an appropriate review protocol. Then, 41 related articles are selected by using exclusion and inclusion criteria. Majority of the studies reviewed had been conducted in the field of data-hiding (particularly steganography) technologies. In this review, various steganographic methods that have been applied in different human biometrics are investigated. Thereafter, these methods are categorised according to taxonomy, and the results are presented on the basis of human steganography biometric real-time medical systems, testing and evaluation methods, significance of use and applications and techniques. Finally, recommendations on how the challenges associated with data hiding can be addressed are provided to enhance the efficiency of using biometric information processed in any authentication real-time medical system. These recommendations are expected to be immensely helpful to developers, company users and researchers.

Matched MeSH terms: Time Factors
Are Neonatal Trials Better Conducted and Reported over the Last 6 Decades? An Analysis on Their Risk-of-Bias Status in Cochrane Reviews

Lai NM, Ong JMJ, Chen KH, Chaiyakunapruk N, Ovelman C, Soll R

Neonatology, 2019;116(2):123-131.
PMID: 31108494 DOI: 10.1159/000497423

BACKGROUND: The introduction of Neonatology as a subspecialty in 1960 has stimulated an enormous amount of neonatal research. A large proportion of neonatal randomized-controlled trials (RCTs) have been included in the Cochrane reviews, within which methodological quality or risk-of-bias (ROB) assessment is an integral feature.
OBJECTIVES: We described the ROB profile of neonatal RCTs published since the 1950s.
METHODS: We analyzed individual studies within the Cochrane Neonatal reviews published up to December 2016. We extracted the reviewers' judgments on the ROB domains including random sequence generation, allocation concealment, blinding, incomplete outcome data, and selective reporting. We evaluated blinding of personnel in trials in which blinding was considered feasible.
RESULTS: We assessed 1980 RCTs published between 1952 and 2016 from 294 Cochrane Neonatal systematic reviews, with full ROB assessments performed in 848 trials (42.8%). Among the ROB domains, the highest proportion of trials (73%) were judged as satisfactory ("low risk") in handling incomplete outcome data, while fewest trials achieved blinding of outcome assessor (38.4%). In the last 6 decades, a progressive increase has been observed in the proportion of trials that were rated as low risk in random sequence generation, allocation concealment, and selective reporting. However, blinding was achieved in less than half of the trials with no clear improvement across decades (23-44% since the 1980s).
CONCLUSIONS: Despite steady improvement in the overall quality of neonatal RCTs over the last 6 decades, blinding remained unsatisfactory in the majority of the trials.

Matched MeSH terms: Time Factors
The role of psychological detachment in burnout and depression: A longitudinal study of Malaysian workers

Muhamad Nasharudin NA, Idris MA, Loh MY, Tuckey M

Scand J Psychol, 2020 Jun;61(3):423-435.
PMID: 32079048 DOI: 10.1111/sjop.12622

The current study aimed to examine the role of psychological detachment in the relationship between working conditions and burnout and depression. First, the study proposed that job demands would increase burnout after four months but not depression. Second, it proposed that psychological detachment would moderate the impact of job demands and job resources on burnout and depression. Third, it was proposed that the interaction between job demands, job resources and psychological detachment would predict burnout and depression. The longitudinal study design involved 345 workers (at both Time 1 and Time 2). The hierarchical regression analysis showed that increasing psychological detachment reduced the negative relationship between physical demands and depression four months later. In contrast, high psychological detachment increased the negative association between emotional resources and burnout, but not between emotional resources and depression. Overall, this study, in its discovery of the impact of working conditions on psychological health, has made a new contribution to psychological detachment studies by using different sub-constructs of job demands and job resources (i.e., emotional and physical) with four-month gaps, as previous studies did not address the impact within this time frame.

Matched MeSH terms: Time Factors
Fulltext Rapid Detection of Sepsis using CESDA: the Caenorhabditis elegans Sepsis Detection Assay

Tee LF, Tan TL, Neoh HM, Jamal R

Rev Soc Bras Med Trop, 2019 Mar 14;52:e20180300.
PMID: 30892548 DOI: 10.1590/0037-8682-0300-2018

INTRODUCTION: The nematode Caenorhabditis elegans was used as a biological sensor to detect the urine of sepsis patients (CESDA assay).
METHODS: C. elegans was aliquoted onto the center of assay plates and allowed to migrate towards sepsis (T) or control (C) urine samples spotted on the same plate. The number of worms found in either (T) or (C) was scored at 10-minute intervals over a 60-minute period.
RESULTS: The worms were able to identify the urine (<48 hours) of sepsis patients rapidly within 20 minutes (AUROC=0.67, p=0.012) and infection within 40 minutes (AUROC=0.80, p=0.016).
CONCLUSIONS: CESDA could be further explored for sepsis diagnosis.

Matched MeSH terms: Time Factors
Multiclass Benchmarking Framework for Automated Acute Leukaemia Detection and Classification Based on BWM and Group-VIKOR

Alsalem MA, Zaidan AA, Zaidan BB, Albahri OS, Alamoodi AH, Albahri AS, et al.

J Med Syst, 2019 Jun 01;43(7):212.
PMID: 31154550 DOI: 10.1007/s10916-019-1338-x

This paper aims to assist the administration departments of medical organisations in making the right decision on selecting a suitable multiclass classification model for acute leukaemia. In this paper, we proposed a framework that will aid these departments in evaluating, benchmarking and ranking available multiclass classification models for the selection of the best one. Medical organisations have continuously faced evaluation and benchmarking challenges in such endeavour, especially when no single model is superior. Moreover, the improper selection of multiclass classification for acute leukaemia model may be costly for medical organisations. For example, when a patient dies, one such organisation will be legally or financially sued for incidents in which the model fails to fulfil its desired outcome. With regard to evaluation and benchmarking, multiclass classification models are challenging processes due to multiple evaluation and conflicting criteria. This study structured a decision matrix (DM) based on the crossover of 2 groups of multi-evaluation criteria and 22 multiclass classification models. The matrix was then evaluated with datasets comprising 72 samples of acute leukaemia, which include 5327 gens. Subsequently, multi-criteria decision-making (MCDM) techniques are used in the benchmarking and ranking of multiclass classification models. The MCDM used techniques that include the integrated BWM and VIKOR. BWM has been applied for the weight calculations of evaluation criteria, whereas VIKOR has been used to benchmark and rank classification models. VIKOR has also been employed in two decision-making contexts: individual and group decision making and internal and external group aggregation. Results showed the following: (1) the integration of BWM and VIKOR is effective at solving the benchmarking/selection problems of multiclass classification models. (2) The ranks of classification models obtained from internal and external VIKOR group decision making were almost the same, and the best multiclass classification model based on the two was 'Bayes. Naive Byes Updateable' and the worst one was 'Trees.LMT'. (3) Among the scores of groups in the objective validation, significant differences were identified, which indicated that the ranking results of internal and external VIKOR group decision making were valid.

Matched MeSH terms: Time Factors
Fulltext Retention of Carotenes and Vitamin E, and Physico-chemical Changes Occurring upon Heating Red Palm Olein Using Deep-fat Fryer, Microwave Oven and Conventional Oven

Loganathan R, Tarmizi AHA, Vethakkan SR, Teng KT

J Oleo Sci, 2020 Mar 01;69(3):167-183.
PMID: 32051355 DOI: 10.5650/jos.ess19209

Red palm olein is known to be high in carotenes and vitamin E (tocols) and possess various nutritional benefits. This study evaluates the effect of prolonged heating using three common cooking techniques i.e. deep-fat fryer, microwave oven and conventional oven, on the profiles of carotenes and tocols as well as the physico-chemical changes occurring in red palm olein when compared to conventional palm olein. Physico-chemical changes in all oils were gauged based on their peroxide, p-anisidine and total oxidation values, acidity, and fatty acid composition. Both red palm olein and palm olein were thermally stable based on their lower rate of hydrolytic and oxidative degradations as well as higher tocols retention, which allow the oils to undergo heating up to 3 hours using deep-fat fryer and conventional oven. Nevertheless, red palm olein seemed not suitable for prolonged heating processes considering lower retention of carotenes. Microwave heating also influenced the stability of phytonutrients.

Matched MeSH terms: Time Factors
Contact toxicity and residual effects of selected insecticides against the adult Paederus fuscipes (Coleoptera: Staphylinidae)

Bong LJ, Neoh KB, Jaal Z, Lee CY

J Econ Entomol, 2013 Dec;106(6):2530-40.
PMID: 24498755

The contact toxicity of four insecticide formulations (deltamethrin, fipronil, fenitrothion, and imidacloprid) applied on three different substrates (tile, plywood, and concrete) against the adult rove beetle, Paederus fuscipes Curtis, was evaluated. The relative order of speed of killing effects was as follows: deltamethrin > imidacloprid > fipronil > fenitrothion. Although deltamethrin showed the fastest action against P. fuscipes, the recovery rate of rove beetles at 48 h posttreatment was moderate (approximately 25%) on the tile surface to high (approximately 80%) on the plywood surface. Thus, it is likely that the insects did not pick up the lethal dose especially on porous surfaces. In contrast, fipronil demonstrated delayed toxicity that might promote maximal uptake by the insects. More than 80% mortality was registered for tile and plywood surfaces up to 4 wk after exposure. High mortality (almost 100%) was recorded for imidacloprid-exposed P. fuscipes at 48 h posttreatment, but only on the tile surface. Among the four insecticides tested, fenitrothion was the least effective against P. fuscipes because low percentage to no mortality was recorded in the fenitrothion treatment.

Matched MeSH terms: Time Factors
Thermal death kinetics of Mediterranean, Malaysian, melon, and oriental fruit fly (Diptera: Tephritidae) eggs and third instars

Armstrong JW, Tang J, Wang S

J Econ Entomol, 2009 Apr;102(2):522-32.
PMID: 19449631

The late-aged egg and third-instar life stages of laboratory-reared Malaysian fruit fly, Bactrocera latifrons (Hendel); Mediterranean fruit fly, Ceratitis capitata (Wiedemann); melon fly, B. cucurbitae Coquillett; and oriental fruit fly, B. dorsalis (Hendel), (Diptera: Tephritidae); and the third instars of wild Mediterranean fruit fly were exposed to thermal treatments. A heating block system was used to determine the thermal death kinetics of the four fruit fly species. Treatments consisted of heating the fruit fly life stages to 44, 46, 48, and 50 degrees C and holding for different times ranging from 0 to 120 min depending on the thermal mortality response and time required to obtain 100% mortality for each species and life stage. The 0.5-order kinetic model had the best fit to the survival ratio for all the treatment temperatures and was used to predict lethal times. The thermal death time (TDT) curves showed a tolerance order of Mediterranean fruit fly eggs < or = third instars at 44, 46, and 50 degrees C, third instars < or = eggs at 48 degrees C, and wild third instars < the laboratory-reared third instars. Comparison between Mediterranean fruit fly third instar thermotolerance from Hawaii and Israel showed that Israel Mediterranean fruit fly was more thermotolerant. A comparison of minimum treatment times at a given temperature required to obtain 100% mortality of laboratory-reared Malaysian, Mediterranean (Hawaii and Israel strains), melon, Mexican, and oriental fruit fly eggs or third instars and wild Mediterranean fruit fly (Hawaii strain) eggs or third instars showed that oriental fruit fly was the most thermotolerant among the third instars, and the difference in heat tolerance between third instars and eggs was negligible at 50 degrees C.

Matched MeSH terms: Time Factors
Fulltext Synchronous activity lowers the energetic cost of nest escape for sea turtle hatchlings

Rusli MU, Booth DT, Joseph J

J Exp Biol, 2016 05 15;219(Pt 10):1505-13.
PMID: 27207954 DOI: 10.1242/jeb.134742

A potential advantage of group movement in animals is increased locomotion efficiency. This implies a reduced energetic cost for individuals that occur in larger groups such as herds, flocks and schools. When chelonian hatchlings hatch in the underground nest with finite energy for their post-hatching dispersal phase, they face the challenge of minimizing energetic expenditure while escaping the nest. The term 'social facilitation' has been used to describe the combined digging effort of sea turtle hatchlings during nest escape. Given that in a normal clutch, a substantial part of the energy reserve within the residual yolk is used by hatchlings in the digging out process, a decreased cohort size may reduce the energy reserve available to cross the beach and sustain the initial swimming frenzy. This hypothesis was experimentally tested by varying cohort size in hatchling green turtles (Chelonia mydas) and measuring energy expenditure during the nest escape process using open-flow respirometry. The energetic cost of escaping through 40 cm of sand was calculated to vary between 4.4 and 28.3 kJ per individual, the cost decreasing as the number of individuals in the cohort increased. This represents 11-68% of the energy contained in a hatchling's residual yolk at hatching. The reduced energetic cost associated with large cohorts resulted from both a lower metabolic rate per individual and a shortened nest escape time. We conclude that synchronous digging activity of many hatchlings during nest escape evolved not only to facilitate rapid nest emergence but also to reduce the energetic cost to individuals.

Matched MeSH terms: Time Factors
Fulltext Gliding saves time but not energy in Malayan colugos

Byrnes G, Libby T, Lim NT, Spence AJ

J Exp Biol, 2011 Aug 15;214(Pt 16):2690-6.
PMID: 21795564 DOI: 10.1242/jeb.052993

Gliding is thought to be an economical form of locomotion. However, few data on the climbing and gliding of free-ranging gliding mammals are available. This study employed an animal-borne three-dimensional acceleration data-logging system to collect continuous data on the climbing and gliding of free-ranging Malayan colugos, Galeopterus variegatus. We combined these movement data with empirical estimates of the metabolic costs to move horizontally or vertically to test this long-standing hypothesis by determining whether the metabolic cost to climb to sufficient height to glide a given distance was less than the cost to move an equivalent distance horizontally through the canopy. On average, colugos climb a short distance to initiate glides. However, due to the high energetic cost of climbing, gliding is more energetically costly to move a given horizontal distance than would be predicted for an animal travelling the same distance through the canopy. Furthermore, because colugos spend a small fraction of their time engaged in locomotor activity, the high costs have little effect on their overall energy budget. As a result, the energetic economy hypothesis for the origins of gliding is not supported. It is likely that other ecologically relevant factors have played a greater role in the origins of gliding in colugos and other mammals.

Matched MeSH terms: Time Factors
Long-term changes in liana loads and tree dynamics in a Malaysian forest

Wright SJ, Sun IF, Pickering M, Fletcher CD, Chen YY

Ecology, 2015 Oct;96(10):2748-57.
PMID: 26649395 DOI: 10.1890/14-1985.1

The importance of lianas through time and their effect on tree reproduction are evaluated for the first time in a Southeast Asian Dipterocarp forest. We quantified flower and seed production by lianas and trees for 13 years, assessed liana loads in the crowns of all trees larger than 30 cm in diameter at breast height (1.3 m) in 2002 and 2014, and assessed levels of reproduction for the same trees during a strong general flowering event in 2014 for the 50-ha forest dynamics plot at the Pasoh Forest Reserve, Malaysia. General flowering refers to synchronous reproduction by hundreds of plant species at irregular, multiyear intervals and only occurs in Southeast Asian Dipterocarp forests. Overall, lianas were present in 50% of tree crowns and comprised 31% of flower production and 46% of seed production. Lianas reduced growth, survival, and reproduction by their host trees. Lianas were less frequent in canopy- emergent trees, Dipterocarps comprised a disproportionately large proportion of canopy emergents, and, as a consequence, lianas were less frequent in Dipterocarps than in trees from other plant families. Lianas infested the crowns of significantly fewer trees in 2014 (47.9%) than in 2002 (52.3%); however, the decrease was restricted to trees with the lightest liana loads and sample sizes and statistical power were enormous. Lianas comprised a stable proportion of flower production and a highly variable proportion of seed production from 2002 through 2013. We conclude lianas have a huge impact on trees in this forest and were a stable component of the forest between 2002 and 2014. The emergent habit and associated ability to avoid lianas might contribute to the success of the Dipterocarpaceae.

Matched MeSH terms: Time Factors
Comparison of condition index in the green-lipped mussel Perna viridis between Sebatu and Pasir Panjang, Peninsular Malaysia

Al-Barwani SM, Arshad A, Amin SMN, Rahman A

J Environ Biol, 2016 07;37(4 Spec No):705-8.
PMID: 28779729

The condition index (which relates to the tissue dry weight to shell volume) of the green-lipped mussel Perna viridis was investigated at Sebatu in Melaka and Pasir Panjang in Negri Sembilan from September 2003 to February 2004. Monthly samples of P. viridis were collected from culturing rafts at both sites. Variations in the average monthly condition index (CI) of P. viridis ranged from 21.06 to 26.72 g cm(-3) and 15.18 to 19.41 g cm(-3) in Sebatu and Pasir Panjang, respectively. Salinity values were lowest in November between 27.93 to 28.10 ppt in Sebatu and Pasir Panjang, respectively. Salinity then started increasing gradually until it reached 33.26 ppt in Sebatu and 31.23 ppt in Pasir Panjang in the month of February. Chlorophylla in Pasir Panjang showed higher fluctuation, ranging from 2.93 to 14.39 mg/L, while in Sebatu the fluctuations were lower and ranged between 7.70 and 9.37 mg l(-1). Rapid decline in CI values were recorded during January in Sebatu and February in Pasir Panjang. However, this rapid declining state of CI in P. viridis was an indication of its spawning period, when their gametes were released in the water column. These findings would help in the development of captive breeding techniques and mass seed production in aquaculture.

Matched MeSH terms: Time Factors
Temporal coexistence mechanisms contribute to the latitudinal gradient in forest diversity

Usinowicz J, Chang-Yang CH, Chen YY, Clark JS, Fletcher C, Garwood NC, et al.

Nature, 2017 10 05;550(7674):105-108.
PMID: 28953870 DOI: 10.1038/nature24038

The tropical forests of Borneo and Amazonia may each contain more tree species diversity in half a square kilometre than do all the temperate forests of Europe, North America, and Asia combined. Biologists have long been fascinated by this disparity, using it to investigate potential drivers of biodiversity. Latitudinal variation in many of these drivers is expected to create geographic differences in ecological and evolutionary processes, and evidence increasingly shows that tropical ecosystems have higher rates of diversification, clade origination, and clade dispersal. However, there is currently no evidence to link gradients in ecological processes within communities at a local scale directly to the geographic gradient in biodiversity. Here, we show geographic variation in the storage effect, an ecological mechanism that reduces the potential for competitive exclusion more strongly in the tropics than it does in temperate and boreal zones, decreasing the ratio of interspecific-to-intraspecific competition by 0.25% for each degree of latitude that an ecosystem is located closer to the Equator. Additionally, we find evidence that latitudinal variation in climate underpins these differences; longer growing seasons in the tropics reduce constraints on the seasonal timing of reproduction, permitting lower recruitment synchrony between species and thereby enhancing niche partitioning through the storage effect. Our results demonstrate that the strength of the storage effect, and therefore its impact on diversity within communities, varies latitudinally in association with climate. This finding highlights the importance of biotic interactions in shaping geographic diversity patterns, and emphasizes the need to understand the mechanisms underpinning ecological processes in greater detail than has previously been appreciated.

Matched MeSH terms: Time Factors
A robust real-time gait event detection using wireless gyroscope and its application on normal and altered gaits

Gouwanda D, Gopalai AA

Med Eng Phys, 2015 Feb;37(2):219-25.
PMID: 25619613 DOI: 10.1016/j.medengphy.2014.12.004

Gait events detection allows clinicians and biomechanics researchers to determine timing of gait events, to estimate duration of stance phase and swing phase and to segment gait data. It also aids biomedical engineers to improve the design of orthoses and FES (functional electrical stimulation) systems. In recent years, researchers have resorted to using gyroscopes to determine heel-strike (HS) and toe-off (TO) events in gait cycles. However, these methods are subjected to significant delays when implemented in real-time gait monitoring devices, orthoses, and FES systems. Therefore, the work presented in this paper proposes a method that addresses these delays, to ensure real-time gait event detection. The proposed algorithm combines the use of heuristics and zero-crossing method to identify HS and TO. Experiments involving: (1) normal walking; (2) walking with knee brace; and (3) walking with ankle brace for overground walking and treadmill walking were designed to verify and validate the identified HS and TO. The performance of the proposed method was compared against the established gait detection algorithms. It was observed that the proposed method produced detection rate that was comparable to earlier reported methods and recorded reduced time delays, at an average of 100 ms.

Matched MeSH terms: Time Factors
Fulltext Delayed intracranial haemorrhage in head injury

Zahari M, Mohd Ali AK, Chandrasekharan S

Singapore Med J, 1996 Jun;37(3):285-7.
PMID: 8942231

To determine the incidence of delayed intracranial haemorrhage and the indication for repeat computed tomography (CT), a one and a half year retrospective study was made. A total of 289 patients had CT scan for head injury of which 78 (26.9%) had multiple scans. Out of these, 5 patients developed delayed haemorrhages (one extradural, one subdural, and three intracerebral haematoma). The incidence of delayed intracranial haemorrhage in our series is small when compared with others. The main predisposing factors are decompressive surgery, hyperventilation and cerebral dehydration therapy. It is important to know when to repeat the CT scan. A review of the literature regarding this aspect is presented and compared with our protocol. Intracranial pressure monitoring plays an increasingly important role in the management of head injury and should be used to decide the patient requiring repeat CT. Follow-up CT without other indication is not necessary.

Matched MeSH terms: Time Factors
Fulltext Coitus and orgasm at term: effect on spontaneous labour and pregnancy outcome

Tan PC, Yow CM, Omar SZ

Singapore Med J, 2009 Nov;50(11):1062-7.
PMID: 19960160

INTRODUCTION: Coitus and orgasm in late pregnancy are believed to facilitate the onset of labour. We aim to evaluate the relationship at term of reported coitus and orgasm with spontaneous labour.
METHODS: Women at term scheduled for non-urgent labour induction were asked to keep a coitus and orgasm diary. These women were recruited for a randomised trial on the effect of coitus to promote spontaneous labour. For this analysis, the women were categorised into coitally-active and abstinent groups according to their coital diary. Spontaneous labour prior to the date of scheduled labour induction was the primary outcome. Labour, delivery and neonatal outcome were also evaluated. Multivariable logistic regression analysis was used to control for significant variables.
RESULTS: On univariate analysis, the inverse association of coitus with spontaneous labour was borderline (odds ratio [OR] 0.6; 95 percent confidence interval [CI] 0.3-1.0; p-value is 0.052). Orgasm was not associated with spontaneous labour (p-value is 0.33). After adjustment, coitus (adjusted OR 0.4; 95 percent CI 0.2-0.8; p-value is 0.009) displayed a significant inverse association with spontaneous labour. Coitus and orgasm were not associated with any other adverse pregnancy outcome.
CONCLUSION: Women who reported coitus were less likely to go into spontaneous labour prior to their scheduled labour induction. Reported coitus and orgasm were not associated with adverse pregnancy outcome.

Matched MeSH terms: Time Factors
Fulltext A delayed unusual presentation of a penetrating foreign body

Lee ST

Singapore Med J, 1992 Jun;33(3):304-5.
PMID: 1631596

Complications resulting from the penetrating percutaneous foreign bodies almost always arise in the early post injury period. Delayed presentations of previous asymptomatic foreign bodies are rare. In this case report, symptoms of tracheal irritation arose seven years following the initial penetrating shrapnel injury to the neck. Computed tomography scans enabled localisation of the foreign body at the tracheal wall and carotid sheath interface. The usefulness of this radiologic modality in the evaluation of the penetrating soft tissue injury is highlighted. A review of the phenomenon of the migrating and asymptomatic foreign body follows.

Matched MeSH terms: Time Factors
Analysing the accuracy of machine learning techniques to develop an integrated influent time series model: case study of a sewage treatment plant, Malaysia

Ansari M, Othman F, Abunama T, El-Shafie A

Environ Sci Pollut Res Int, 2018 Apr;25(12):12139-12149.
PMID: 29455350 DOI: 10.1007/s11356-018-1438-z

The function of a sewage treatment plant is to treat the sewage to acceptable standards before being discharged into the receiving waters. To design and operate such plants, it is necessary to measure and predict the influent flow rate. In this research, the influent flow rate of a sewage treatment plant (STP) was modelled and predicted by autoregressive integrated moving average (ARIMA), nonlinear autoregressive network (NAR) and support vector machine (SVM) regression time series algorithms. To evaluate the models' accuracy, the root mean square error (RMSE) and coefficient of determination (R2) were calculated as initial assessment measures, while relative error (RE), peak flow criterion (PFC) and low flow criterion (LFC) were calculated as final evaluation measures to demonstrate the detailed accuracy of the selected models. An integrated model was developed based on the individual models' prediction ability for low, average and peak flow. An initial assessment of the results showed that the ARIMA model was the least accurate and the NAR model was the most accurate. The RE results also prove that the SVM model's frequency of errors above 10% or below - 10% was greater than the NAR model's. The influent was also forecasted up to 44 weeks ahead by both models. The graphical results indicate that the NAR model made better predictions than the SVM model. The final evaluation of NAR and SVM demonstrated that SVM made better predictions at peak flow and NAR fit well for low and average inflow ranges. The integrated model developed includes the NAR model for low and average influent and the SVM model for peak inflow.

Matched MeSH terms: Time Factors
Retrospective analysis of factors affecting rate of skeletonization within a tropical climate

Gunawardena SA, Abeyratne P, Jayasena A, Rajapaksha S, Senadhipathi H, Siriwardana D, et al.

Sci Justice, 2023 Sep;63(5):638-650.
PMID: 37718011 DOI: 10.1016/j.scijus.2023.08.001

Estimating the post mortem interval (PMI) in skeletonized cases is an extremely challenging exercise. Sri Lanka lacks adequate taphonomic research which is a serious limitation when assessing PMI in forensic death investigations. Methods that have been proposed to estimate PMI using the total body score (TBS) and accumulated degree days (ADD) are mainly based on data from continental and temperate climates and have shown less reliability in tropical climates. With the intention of developing a region-specific, evidence-based guide which would be applicable to tropical climates like Sri Lanka, we selected thirteen skeletonized remains with known PMIs from forensic case records and analysed their taphonomy in relation to selected weather data. We also compared the ADD values within our dataset with reference ranges calculated using published formula. All except one were found from outdoor locations. The TBS ranged from 24 to 32 and had a weak positive correlation with the PMI. The earliest appearance of skeletonization was 15 days in a body found indoors. The highest rate of skeletonization was seen in a body with a TBS of 32 and a PMI of 23 days. The average daily temperature and relative humidity were similar across all the cases however, the amount of rainfall varied. Bodies exposed to monsoon rains (n = 6) had a lower mean rate of skeletonization compared to those that were not exposed (n = 4) suggesting lower rates of decomposition during periods of heavy rainfall. No correlation was found between ADD and TBS. In 9 (69.2%) cases, the actual ADD was much lower than reference ADD ranges for TBS values, indicating poor applicability of TBS and ADD based formulae in estimating PMI within the Sri Lankan climate. Our study shows a strong need for taphonomic and entomological research in tropical climates to further explore the impact of monsoons on biotic and abiotic factors affecting skeletonization.

Matched MeSH terms: Time Factors
Fulltext Emergency traffic adaptive MAC protocol for wireless body area networks based on prioritization

Masud F, Abdullah AH, Abdul-Salaam G

PLoS One, 2019;14(12):e0225518.
PMID: 31790457 DOI: 10.1371/journal.pone.0225518

This paper proposes an emergency Traffic Adaptive MAC (eTA-MAC) protocol for WBANs based on Prioritization. The main advantage of the protocol is to provide traffic ranking through a Traffic Class Prioritization-based slotted-Carrier Sense Multiple Access/Collision Avoidance (TCP-CSMA/CA) scheme. The emergency traffic is handled through Emergency Traffic Class Provisioning-based slotted-CSMA/CA (ETCP-CSMA/CA) scheme. The emergency-based traffic adaptivity is provided through Emergency-based Traffic Adaptive slotted-CSMA/CA (ETA-CSMA/CA) scheme. The TCP-CSMA/CA scheme assigns a distinct, minimized and prioritized backoff period range to each traffic class in every backoff during channel access in Contention Access Period (CAP). The ETCP-CSMA/CA scheme delivers the sporadic emergency traffic that occurs at a single or multiple BMSN(s) instantaneously, with minimum delay and packet loss. It does this while being aware of normal traffic in the CAP. Then, the ETA-CSMA/CA scheme creates a balance between throughput and energy in the sporadic emergency situation with energy preservation of normal traffic BMSNs. The proposed protocol is evaluated using NS-2 simulator. The results indicate that the proposed protocol is better than the existing Medium Access Control (MAC) protocols by 86% decrease in packet delivery delay, 61% increase in throughput, and a 76% decrease in energy consumption.

Matched MeSH terms: Time Factors

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