Southwestern Iran Research Articles

A committee machine with intelligent experts (CMIE) for estimation of fast and slow shear wave velocities utilizing petrophysical logs

Petrophysical properties determination of a reservoir such as shear wave velocity plays a crucial role in exploration and production management. The purpose of this study is to develop a robust committee machine model for estimating fast and slow shear wave velocities from petrophysical logs. To this end, appropriate inputs were determined and different algorithms including artificial neural network, fuzzy logic and neuro-fuzzy were applied. Afterward, the obtained outputs were merged by utilizing optimization methods consisting of Ant Colony Optimization for Continuous Domain, Genetic and Simulated Annealing approaches. The construction of the committee machine was done using a case study including 2000 data samples from the Sarvak Formation in one of the southwestern Iran oilfields. The utilized dataset was divided into training and testing data which contain 1600 and 400 samples, respectively. Mean Squared Error was presented as a determinative factor for evaluating system performance. To obtain the best system performance with the lowest Mean Squared Error, the parameters setting of each algorithm were coded in different ranges. A total 52416, 76896 and 29400 cases were run to optimize the parameter settings of genetic algorithms, simulated annealing and continues ant colony optimization models, respectively. A weight factor is assigned to each method indicating their contribution in the final estimation. The desirable weights' combination is acquired using optimization methods. Among the individual systems, fuzzy logic and artificial neural network obtained the best performance for estimating fast and slow shear wave velocities, respectively. Also, the results of committee machine algorithms indicate a well optimization on individual systems and have superior performance over them. The most efficient optimization algorithms in the structure of committee machines for fast shear wave velocity are Genetic and Simulated Annealing and for slow shear wave velocity is Genetic Algorithm, in terms of Mean Squared Error criteria.

Prevalence and molecular characterization of Giardia duodenalis in small ruminants of Shiraz, southwestern Iran: A zoonotic concern

Livestock are commonly affected by gastrointestinal protozoan parasites, including Giardia duodenalis. In small ruminants, G. duodenalis infection may decrease carcass weight and dressing percentage. Current study was done to determine the prevalence, assemblage distribution, and zoonotic significance of Giardia infection in sheep and goats in Shiraz, southwestern Iran. In total, 200 fecal samples were randomly collected from 100 sheep and 100 goats in 10 farms in Shiraz, southwest of Iran (June 2021-February 2022) and directly examined for G. duodenalis cyst by saline/iodine wet mount examination using a light microscope (400 ×). Positive samples were further genotyped using a nested-PCR and sequencing methods. A mean prevalence of 5.5% (11/200) was estimated for G. duodenalis infection among small ruminants, with 7% and 4% for sheep and goats, respectively. Next, 9 out of 11 positive samples were amplified and only 5 were successfully sequenced at the tpi locus. Our results showed that 80% (4/5) isolates belonged to assemblage E, while only 20% (1/5) were associated with the assemblage A (subtype AI). Of note, 2 E assemblages were isolated from goats and 2 E assemblages plus 1 assemblage A were isolated from sheep. The major finding in the present study was the isolation of assemblage A from sheep in Shiraz, highlighting the zoonotic transmission of Giardia infection in the study area. In general, the information mentioned in the present study is very limited and more extensive studies in this field are needed to achieve more conclusive results.

Procalcitonin as a Prognostic Factor in Patients with COVID-19 in Southwestern Iran.

There is increasing evidence supporting a central role of the viral-induced hyper-inflammatory immune response in the pathogenesis of COVID-19. Serum procalcitonin (PCT) is an emerging prognostic marker in coronavirus disease 2019 (COVID-19). The aim of this study was to investigate the relationship between serum procalcitonin and clinical severity and outcomes in patients with coronavirus disease 2019 (COVID-19). Hematological and biochemical parameters were evaluated in patients with COVID-19 infection from February to April 2020 at Hajar Hospital in the Shahrekord University of Medical Science, Shahrekord, Iran. The results showed that total lymphocyte counts, albumin, calcium, and creatinine levels were significantly different between the two moderate and severe groups, and the mean of procalcitonin level in COVID-19 patients with severe disease was higher (0.36 ng/mL) compared with the patients with moderate disease, and its level was found to be >5 ng/mL in 14.2% of5 ng/mL in 14.2% of patients in the former group. PCT may be a marker of disease severity in COVID-19 and may contribute to determining the severity of patients infected with SARS-CoV-2. Moreover, serial PCT measurements may be beneficial in predicting the prognosis.

The use of intelligent search algorithms in the cost optimization of road pavement thickness design

Since road pavements consume a significant portion of the financial resources of construction costs, design engineers aim to find an appropriate pavement thickness design with minimum possible cost. The optimal design can be located using intelligent search algorithms. This study compares the performance of genetic algorithm and particle swarm optimization to determine the efficacy of intelligent algorithms in determining the economically optimal pavement thickness design. The software required to implement the two algorithms for solving the pavement design and the simulation–optimization model were developed. Then, nine completed projects in Khuzestan, in Southwestern Iran, were evaluated using the manual design approach of consulting engineers, and the projects’ capabilities were compared by applying the programs developed for the two algorithms to the projects. The results indicated using GA and PSO reduced design costs by 9–26.5% and 5–25%, respectively compared to the manual design, and GA outperforms PSO by 1–5.5% regarding cost savings.

Suicidal ideation and its related factors among older adults: a population-based study in Southwestern Iran

ObjectivesSuicidal ideation is a major risk factor for suicide and can negatively affect self-care and health behaviors among the older adults. There are limited data on the prevalence and risk factors of suicidal ideation among the older population during the COVID-19 pandemic. The aim of the present study was to examine the prevalence and risk factors of suicidal ideations among Iranian older adults during the COVID-19 pandemic.MethodsA total of 803 older community adults in Shiraz (Southwestern Iran) were surveyed to determine potential factors influencing suicidal ideation, including demographic factors, physical health status, access to healthcare, current depression status, fear of COVID-19, perceived social support, and social engagement. Data were collected utilizing face-to-face interviews between November and December 2020. Multivariate logistic regression analysis was used to identify independent variables associated with suicidal ideations.ResultsAmong the 803 participants, 69 reported suicidal ideations (8.6%). Individuals with suicidal ideations were more likely to have greater fear of COVID-19. However, based on the results of multivariate logistic regression analysis, current depression (OR: 2.07, CI 95%: 1.18–3.65), not being married (OR: 1.82, CI 95%: 1.06–3.13), inability to pay for medical bills (OR: 2.16, CI 95%: 1.23–3.79), low perceived social support (OR: 2.03, CI95%: 1.11–3.71), and having limited social network (OR:1.77, CI 95%: 1.02–3.10) appeared to be more powerful influencing factors.ConclusionSuicidal ideation appears to be relatively common among Iranian older adults during the COVID-19 pandemic. A lack of longitudinal data makes it difficult to establish an association between suicidal ideations and the COVID-19 pandemic. Systematic monitoring of suicidal ideation is recommended among high-risk groups, particularly the older population.

Foraminiferal biozonation, biostratigraphy and trans-basinal correlation of the Oligo-Miocene Qom Formation, Iran (northeastern margin of the Tethyan Seaway)

During the Rupelian–Burdigalian (early Oligocene–early Miocene), the Qom Formation was deposited along the northeastern margin of the Tethyan Seaway in the Sanandaj–Sirjan, Urumieh–Dokhtar, and Central Iran basins. The biostratigraphic data from a total of 1152 thin sections from 10 outcrop sections along over 1000 km of the Tethyan Seaway margin are presented. A larger benthic foraminiferal (LBF) biozonation, consisting of five biozones, is proposed for dating the Rupelian–Burdigalian Qom Formation. It is correlated with global planktonic zones, LBF zones, southeastern Asian “Letter Stages”, shallow benthic foraminiferal zones (SB-zones) of southern European basins, and newly revised zones of the Asmari Formation in southwestern Iran. This biozonation subdivides the Rupelian stage into “early Rupelian” and “late Rupelian”, based on the first appearances of lepidocyclinids in the latter one. The early Rupelian strata are characterized by the presence of Nummulites without lepidocyclinids which are reported merely from southwestern and southern Kashan, where the thickest Rupelian deposits of the Qom Formation are recorded. The basal layers of the Qom Formation in southeasternmost outcrops (northwestern Jazmurian Lake) are late Rupelian in age based on the co-occurrence of lepidocyclinids and Nummulites spp. By comparison of the well-documented transgression of the Tethyan Seaway over the Iranian plate (from southeast to northwest) and the limitation of all reported early Rupelian strata of the Qom Formation to southwestern and southern Kashan, the following scenarios can be supposed: 1) the oldest deposits could be deposited in southeastern Iran, but they have not been reported, yet; 2) during early Rupelian, there was a transgression from the Zagros Basin to southwestern and southern Kashan areas, then the transgression progressed both northwestward and southeastward.

The effectiveness of drought adaptation strategies in explaining the livability of Iranian rural households

Rural areas, where most people depend on agriculture, are extremely vulnerable to the drought that destroys agriculture, depopulates villages, and drastically reduces rural household livability (RHL). However, previous studies tended to focus on the adoption of drought adaptation strategies without defining and prioritizing their effectiveness to improve RHL. This study aimed to fill this gap in previous research by evaluating drought adaptation strategies' effectiveness to explain RHL in Iran. The participants of the study were all rural households in Hindijan city, Khuzestan province (southwest of Iran). To evaluate the adaptation strategies at RHL level, 42 strategies were classified into six categories (farm management, crop management, financial management, irrigation and water management, social activities and physical infrastructure management). According to the results, the studied rural households in southwestern Iran had low livability. The results also showed that the six adaptation categories explained 64.2% of the variance in RHL under drought conditions, which is quite a significant level. The most important adaptation classes under drought conditions were farming strategies and crop management. Overall, these results can be used to improve RHL and drought management for policymakers in this area.

Surface Displacement and Source Parameters of the 2021 Bandar-e Genaveh, Iran, Earthquake Determined from InSAR Observations

On 18 April 2021, a MW 5.8 earthquake occurred near the city of Bandar-e Genaveh, southwestern Iran. Four synthetic aperture radar (SAR) images, acquired from Sentinel-1 (ESA Copernicus project) satellites in ascending and descending orbits, were used to get two displacement maps, catching the surface co-seismic effects through the two-pass InSAR technique. Modeling the deformation patterns using equations for a shear dislocation in elastic half-space allowed the source parameters and the slip distribution of the seismogenic source to be determined. We calculated that the rupture occurred on a reverse fault extending NW-SE, gently dipping NE and with a maximum slip reaching about 1 m. The northeast and low-dip angle of this fault are also consistent with the tectonics of the region, which is subject to deformation and shortening along the northern margin of the Arabian plate. Our estimations of the fault parameters agree with the Zagros Foredeep reverse fault. We additionally processed four other SAR images to investigate the possibility that the Mw 5.0 aftershock, which occurred about one month later, induced surface effects visible with InSAR. This analysis, however, did not provide any clear conclusions.

Identification of mutations in rpoB, pncA, embB, and ubiA genes among drug-resistant Mycobacterium tuberculosis clinical isolates from Iran.

Mycobacterium tuberculosis resistant to effective first-line drugs (FLDs) has challenged national and global tuberculosis control programs. This study aimed to identify mutations in 4 genes related to rifampin, pyrazinamide, and ethambutol resistance among clinical isolates of M. tuberculosis from southwestern Iran. After drug susceptibility testing of 6620 M. tuberculosis clinical isolates by proportional method, a total of 24 FLD-resistant strains were included in the study. Fragments of rpoB, pncA, embB, and ubiA genes were amplified and sequenced to mine the mutations by pairwise alignment with the corresponding M. tuberculosis H37Rv genes. Phenotypic resistance to rifampin, isoniazid, and ethambutol was detected in 67, 54, and 33% (n = 16, 13, and 8) of the isolates, respectively. Of rifampin-resistant isolates, 31% (5/16) were mono-resistant, and 56% (9/16) were multidrug-resistant (MDR). In 100% of rifampin-resistant isolates, mutations were found in the rifampin resistance-determining region (RRDR) of the rpoB, with S450L substitution being the most common, especially in MDRs (77.8%, 7/9). Resistance-conferring mutations in pncA were present in 12.5% (3/24) of FLD-resistant isolates. The embB and ubiA mutations were found in 62.5 and 12.5% (5/8 and 1/8) of ethambutol-resistant isolates, respectively, of which the embB D354A was the most common substitution (37.5%, 3/8). Sixteen distinct mutations were identified, one of which was novel. The sequence analysis of the RRDR segment was the best way to detect rifampin resistance. The rpoB S450L substitution could be a helpful molecular marker to predict MDR. In other genes, no mutation was identified as a reliable marker.

The Time-trend of Multiple Sclerosis Incidence and Prevalence in Khuzestan Province, Iran

Background: The prevalence and incidence of Multiple Sclerosis (MS) have increased in Iran. Objectives: This study aimed to observe the temporal trends and provide a predictive model in the prevalence and incidence of MS in Khuzestan Province, Iran. Materials & Methods: This cross-sectional study was performed from 2006 to 2019 in Khuzestan Province, Southwestern Iran, on 2676 patients registered in the Khuzestan Multiple Sclerosis Center. The simple exponential smoothing model was used to study the time trends and predict the prevalence and incidence of MS in 2020. Results: The mean±SD age of the examined patients with MS was 31.40±8.94 years; while the mean±SD age-incidence of MS was 29.19±9.16 years. The sex ratio (female to male) was measured as 3.05. The patients’ prevalence and average annual incidences were 57.77 and 4.35per 100000 individuals from 2006 to 2019, respectively. The trend in the MS incidence has been upward with a very slight slope during the years 2006 to 2019. The slope of the increase from 2006 to 2019 was higher for women than men. Conclusion: The collected results suggested that Khuzestan Province is a high-risk area for MS; the prevalence and incidence of the disease are increasing, especially in women. We prognosticate a slight increase in the incidence of MS in the age group of 20 to 50 years. However, the prevalence of the disease in this age group was similar to 2019.

Microfacies and depositional environment of Tarbur Formation (Upper Cretaceous‐Lower Palaeocene) Zagros area, southwestern Iran

Over 3,000 m of Upper Cretaceous‐Lower Palaeocene sediments belonging to the Tarbur Formation were studied in seven stratigraphic sections around Shiraz city (south Zagros Basin, SW of Iran). The Tarbur Formation is divided into two informal lithostratigraphic units: a lower well‐bedded rudist limestone and an upper massive rudist limestone. Both units comprise rudist particles as a major organo‐detrital component. Microscopic studies have identified the presence of the following carbonate microfacies types in the Tarbur Formation: rudist orbitoid wackestone, miliolid algal‐bioclast wackestone, rudist packstone, rudist orbitoid packstone, rudist intraclast miliolid packstone, rudist‐agglutinated foraminifer grainstone, orbitoid rudist grainstone, rudist‐hyaline foraminifer‐intraclast grainstone, rudist boundstone and coral boundstone, which are attributed to shallow water lagoon, bar and fore‐reef palaeoenvironments. The rudist fragments co‐existed with a Campanian/Maastrichtian foraminiferal assemblage. The stratigraphic distribution of the investigated microfacies was affected by vertical displacement of studied area basement faults.

Occurrence, genetic characterization, and zoonotic importance of Giardia duodenalis in various species of rodents (Mus musculus, Rattus norvegicus, and Rattus rattus)

Giardia duodenalis is a well-known flagellated parasite and the causative agent of protozoal diarrhea in animals and humans worldwide. Current study was aimed at determination of G. duodenalis prevalence, genetic variation and zoonotic significance in various species of rodents in Shiraz, southwestern Iran. In brief, 120 fecal specimens were collected from rodents (Rattus rattus, Rattus norvegicus, and Mus musculus) during May up to November 2021 and microscopically examined for Giardia cysts. Further molecular characterization of positive samples was done by nested-PCR, followed by nucleotide sequencing of the triose phosphate isomerase (tpi) gene. A total prevalence of 3.3% (4/120) was observed in rodents, with highest rate in black rats [5% (2/40)]. Regarding brown rats and house mice, only one sample was found to be positive, showing 2.5% and 2.5% prevalence, respectively. It is noteworthy that Giardia B and G assemblages were found in black rats (one case/genotype), whereas the only positive samples from brown rats and house mice were characterized as assemblage G. The major findings of the present study were the presence of both zoonotic and non-zoonotic Giardia assemblages in examined rats in Shiraz and the potential of black rats to harbor Giardia infection to humans. These concerns should be taken seriously in terms of public health. Nevertheless, the true epidemiology and assemblage distribution of Giardia is still open to question.

Sustainable water resources management under population growth and agricultural development in the Kheirabad river basin, Iran

In this study, an integrated system dynamics model was developed for scenario analysis in sub-sectors of the Kheirabad River Basin in southwestern Iran where managing water resources is seriously challenging due to population growth and periodic drought. Afterward, the variability of water demand and supply under baseline scenario and different water demand management policies, including water conservation and water pricing, was evaluated. Findings illustrated that with increasing population and cropland area if no further demand management policies were implemented, the total water demand and withdrawal of water resources increase by more than 0.75% annually. The annual surface water availability during 2018-2030 is expected to decrease by around -1.23%. Under these circumstances, the sustainability index of the water resources system is equal to 0.703, indicating that the water system would not be able to meet the total water demand in the near future. However, the water resource sustainability index increases significantly by improving irrigation efficiency and changing crop patterns at the basin. Also, the reduction in per capita water demand and domestic water pricing under the competition structure would help to improve the sustainability index to 0.963 and 0.749, respectively.

Mesostigmata diversity by manure type: a reference study and new datasets from southwestern Iran

Manure-inhabiting Mesostigmata mites are important biological control agents of pest flies. However, the biodiversity of this mite community is mainly known from Europe and America, and especially from cattle manure. This study examined the diversity and abundance of Mesostigmata mites associated with various types of manure in an (intensive) agricultural region of the Middle East, i.e., the city Ahvaz and its suburbs, in southwest Iran. Mite samples were extracted from manure of cattle, buffalo, sheep, horse, poultry and quail in 30 livestock and poultry farms. In total, 40 species belonging to 24 genera and 16 families were identified. The most diverse families were Laelapidae with eight species, Macrochelidae with seven and Parasitidae with six. Macrocheles muscaedomesticae and Uroobovella marginata were the most widespread species, recorded in 28 and 27 out of 30 collection sites, respectively. Two species, M. sumbaensis and U. marginata, were found in all studied manures. Simpson’s diversity index recorded the highest diversity in buffalo and sheep manure. Real and theoretical species richness (rarefaction curves) were congruent in number of individuals. The presence of seven species of Macrochelidae in the manure confirms that these are important predators of the house fly for the region of Ahvaz and its suburbs. Members of the Parasitidae were highly prevalent, with one species known as a specialized predator of house fly eggs. This work aims to encourage further studies on the diversity of Mesostigmata in these agricultural settings, and further continue assessing the feasibility of these mites as effective biocontrol agents of filth flies in different types of manure and from different corners of the world.

Molecular characterization of Trichomonas infections in women of Ilam City, southwestern Iran.

Trichomoniasis is a sexually transmitted infection (STI) caused by the flagellated protozoan Trichomonas vaginalis. Little information is available on the epidemiology and genetic diversity of T. vaginalis in Ilam City, southwestern Iran. A descriptive cross-sectional investigation was carried out between July 2017 and December 2018 on the suspected women patients referred to eight gynecology clinics of Ilam City for probable Trichomonas infection. They were undergone a set of clinical, parasitological, and molecular examinations. During clinical consultation, posterior vaginal fornix secretions and urine samples were gathered from the participants. For the reasons such as physical conditions and cultural and religious constraints, most of participating women, especially young girls due to their virginity, preferred to give urine samples instead of vaginal discharge. The presence of Trichomonas was diagnosed by microscopic examination and molecular detection using conventional PCR targeting ITS1-rDNA. A total of 1765 suspected individuals were examined clinically via vaginal secretions (495 specimens) and urine samples (1270 specimens). Of them, 21 (1.18%) cases, including 13 vaginal secretions and 8 urine samples, were positive for Trichomonas infection by microscopy. Slightly more than half of the patients (11/21, 52.4%) complained of vulvar itching, burning, and frequent urination. Cervical lesions, patchy erythema, and vaginal discharge were recorded in 28.6%, 23.8%, and 19% of the patients respectively. All patients with positive microscopic identification were confirmed by amplification of 450-bp fragment of ITS1-rDNA. Phylogenetic analysis revealed a high rate of genetic homogeneity in which all our isolates together with homologous sequences from China, Philippines, Austria, and USA were clustered within the same clade. A statistically significant relationship was recorded between the patients positive for trichomoniasis and the presence of chronic disease (e.g., diabetes, immune system deficiency).

Calcareous nannofossil biostratigraphy and paleoenvironment of the Eocene–Oligocene interval in the Pabdeh Formation in southwestern Iran

Calcareous nannofossil biostratigraphy and paleoenvironment of the Eocene–Oligocene interval in the Pabdeh Formation in southwestern Iran

Population-based prevalence of polypharmacy and patterns of medication use in southwestern Iran: A cross-sectional study.

Pharmaceutical medications are considered an important component of healthcare delivery and there is a need for its rational use; although there have been major improvements in the pharmaceutical sector in the recent past, inappropriate medication use is considered a major threat to patients' health. Therefore, the pattern of medication use should be monitored routinely. The aim of this study was to investigate the population-based prevalence of polypharmacy and the patterns of medication use in southwestern Iran. We also investigated correlates between polypharmacy and patterns of medication use. Data from the Khuzestan Comprehensive Health Study (KCHS) which consists information of 30 506 with age range to 20 to 65 years were used. Crude and age-standardized prevalence of polypharmacy and their 95% confidence intervals were estimated for different subpopulations. Multivariable Poisson regression modeling was applied, and adjusted prevalence ratios and their 95% confidence intervals were estimated. The Anatomical Therapeutic Chemical classification system (first and second levels) was used for drug classification in different groups based on age, gender, and socioeconomic status. Out of 30 506 adults, 93.3% were not on any medications, and age- and gender-standardized prevalence of polypharmacy was 0.24%. The lowest estimated prevalence was among Arab participants (0.13%). The prevalence of polypharmacy was 1.57% among elderly people, and 4.78% among patients with heart diseases. Socioeconomic status was not associated with polypharmacy (prevalence ratio: 0.95; p= 0.573) but was significantly associated with patterns of medications use for alimentary tract and metabolism and nervous system diseases. The most common drug classes were cardiovascular system (3.93%), alimentary tract and metabolism (2.79%), nervous system (1.01%), systemic hormonal preparations (0.69%), and blood and blood-forming organs (0.38%). The prevalence of polypharmacy is very low in Khuzestan province, especially in the Arab population. Future research is needed to investigate the causes of medication underuse in this population.

The Time-Trend of Multiple Sclerosis Incidence and Prevalence in Khuzestan Province, Iran

Background: The prevalence and incidence of Multiple Sclerosis (MS) have increased in Iran. Objectives: This study aimed to observe the temporal trends and provide a predictive model in the prevalence and incidence of MS in Khuzestan Province, Iran. Methods: This cross-sectional study was performed from 2006 to 2019 in Khuzestan Province, Southwestern Iran, on 2676 patients registered in the Khuzestan Multiple Sclerosis Center. The simple exponential smoothing model was used to study the time trends and predict the prevalence and incidence of MS in 2020. Results: The mean(SD) age of the examined patients with MS was 31.40(8.94) years; while the mean(SD) age-incidence of MS was 29.19(9.16) years. The sex ratio (female to male) was measured as 3.05. The patients' prevalence and average annual incidences were 57.77 and 4.35per 100000 individuals from 2006 to 2019, respectively. The trend in the MS incidence has been upward with a very slight slope during the years 2006 to 2019. The slope of the increase from 2006 to 2019 was higher for women than men. Conclusions: The collected results suggested that Khuzestan Province is a high-risk area for MS; the prevalence and incidence of the disease are increasing, especially in women. We prognosticate a slight increase in the incidence of MS in the age group of 20 to 50 years. However, the prevalence of the disease in this age group was similar to 2019.

Identifying core habitats and corridors of a near threatened carnivore, striped hyaena (Hyaena hyaena) in southwestern Iran

Conservation of large carnivores requires preservation of extensive core habitats and linkages among them. The goal of this study was to identify core habitats and corridors by predicting habitat suitability (an ensemble approach), and calculating resistant kernel and factorial least-cost path modeling for a relatively unknown carnivore, the striped hyaena in Khuzestan area in southwestern Iran. We used the procedure of spatial randomization test to evaluate the coincidence of striped hyaena road crossing with the predicted corridors. The results revealed that elevation, distance to conservation areas, categorical climate and grasslands density were the most influential variables for predicting the occurrence of the striped hyaena in the study area. In the estimated dispersal distance of 70 km, four core habitats were identified. The largest core habitat was located in the northeast of the study area with the highest connectivity contribution. Only about 12% and 1.5% of core habitats and corridors were protected by conservation areas, respectively. Predicted corridors, crossed by roads represented a high risk for striped hyaenas. Adaptive management plan throughout the landscape (conservation of core habitats and corridors, and reducing species mortality on the roads) must be considered by wildlife managers in Iran.

Computational prediction of the drilling rate of penetration (ROP): A comparison of various machine learning approaches and traditional models

Rate of penetration (ROP) prediction, can assist precise planning of drilling operations and can reduce drilling costs. However, easy estimation of this key factor by traditional or experimental models is very difficult. This requires comparing available models for achieving the best prediction approach. In this study, four machine learning (ML) methods and two traditional ROP models were utilized to predict ROP. ML techniques include multilayer perceptron neural network (MLPNN), radial basis function neural network (RBFNN), adaptive neuro-fuzzy inference system (ANFIS), and support vector regression (SVR). MLPNN, ANFIS, and RBFNN methods were trained with four meta-heuristic algorithms including particle swarm optimization (PSO), ant colony optimization (ACO), differential evolution (DE), and genetic algorithm (GA). The backpropagation (BP) algorithm was also incorporated to train the ANFIS and MLPNN methods as a conventional method. For comparison purposes, the traditional ROP models of Bourgoyne and Young (BYM) and Bingham were also implemented in combination with four meta-heuristic algorithms. The required data were collected from the mud logging unit (MLU) and the final report of a drilled well located in southwestern of Iran. In the MLU, the information of different sensors is firstly collected through the data communications protocols and sent to a master unit to be processed into relevant dimensions (i.e. create operational variables). In order to accurately record information, the sensors are calibrated at regular intervals. After removing the outliers, the overall noise of data was reduced by Savitzky-Golay (SG) smoothing filter. Then, in order to simulate a drilling process in a realistic manner and also to evaluate the performance of the models in approximating the penetration rate at greater depth of hole, the available data were divided into 6 sections based on depth. After that, sections 2 Data collection and preprocessing , 3 Methodology , 4 Model development and ROP estimation , 5 Discussion and results , 6 Conclusion were separately used as a test dataset and all previous sections were considered as a training dataset. Results indicated that PSO-MLPNN achieved the highest performance in comparing with other developed models. The concluding remark is that ML models are more efficient and reliable than traditional models. In addition, combining ML models with meta-heuristic algorithms can achieve better results than conventional algorithms such as BP. The results of this study can be used as a practical guide for the management and planning of future well drilling. • Applying Savitzky-Golay (SG) filter to remove noise from data. • Data were divided into 6 sections. Section 2 to 6 were separately noted as test and the previous one(s) as training dataset. • Comparison of four machine learning (ML) methods and two traditional ROP models. • Coupling models with meta-heuristic algorithms and conventional algorithms. • PSO-MLPNNmodel showed the highest accuracy compared to others.