Search results for: grazing incidence small angle x-ray scattering
Commenced in January 2007
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Edition: International
Paper Count: 7405

Search results for: grazing incidence small angle x-ray scattering

6085 Effects of Small Impoundments on Leaf Litter Decomposition and Methane Derived Carbon in the Benthic Foodweb in Streams

Authors: John Gichimu Mbaka, Jan Helmrich Martin von Baumbach, Celia Somlai, Denis Köpfer, Andreas Maeck, Andreas Lorke, Ralf Schäfer

Abstract:

Leaf litter decomposition is an important process providing energy to biotic communities. Additionally, methane gas (CH4) has been identified as an important alternative source of carbon and energy in some freshwater food webs.Flow regulation and dams can strongly alter freshwater ecosystems, but little is known about the effect of small impoundments on leaf litter decomposition and methane derived carbon in streams. In this study, we tested the effect of small water storage impoundments on leaf litter decomposition rates and methane derived carbon. Leaf litter decomposition rates were assessed by comparing treatment sites located close to nine impoundments (Rheinland Pfalz state, Germany) and reference sites located far away from the impoundments.CH4 concentrations were measured in eleven impoundments and correlated with the δ13C values of two subfamilies of chironomid larvae (i.e. Chironomini and Tanypodinae). Leaf litter break down rates were significantly lower in study sites located immediately above the impoundments, especially associated with a reduction in the abundance of shredders. Chironomini larvae had the lower mean δ13C values (‒29.2 to ‒25.5 ‰), than Tanypodinae larvae (‒26.9 to ‒25.3 ‰).No significant relationships were established between CH4 concentrations and δ13C values of chironomids (p> 0.05).Mean δ13C values of chironomid larvae (mean: ‒26.8‰, range: ‒ 29.2‰ to ‒ 25.3‰) were similar to those of sedimentary organic matter (SOM) (mean: ‒28.4‰, range: ‒ 29.3‰ to ‒ 27.1‰) and tree leaf litter (mean: ‒29.8 ‰, range: ‒ 30.5‰ to ‒ 29.1‰). In conclusion, this study demonstrates that small impoundments may have a negative effect on leaf litter decomposition in forest streams and that CH4 has limited influence on the benthic food web in stream impoundments.

Keywords: river functioning, chironomids, Alder tree, stable isotopes, methane oxidation, shredder

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6084 Histopathological Features of Basal Cell Carcinoma: A Ten Year Retrospective Statistical Study in Egypt

Authors: Hala M. El-hanbuli, Mohammed F. Darweesh

Abstract:

The incidence rates of any tumor vary hugely with geographical location. Basal Cell Carcinoma (BCC) is one of the most common skin cancer that has many histopathologic subtypes. Objective: The aim was to study the histopathological features of BCC cases that were received in the Pathology Department, Kasr El-Aini hospital, Cairo University, Egypt during the period from Jan 2004 to Dec 2013 and to evaluate the clinical characters through the patient data available in the request sheets. Methods: Slides and data of BCC cases were collected from the archives of the pathology department, Kasr El-Aini hospital. Revision of all available slides and histological classification of BCC according to WHO (2006) was done. Results: A total number of 310 cases of BCC representing about 65% from the total number of malignant skin tumors examined during the 10-years duration in the department. The age ranged from 8 to 84 years, the mean age was (55.7 ± 15.5). Most of the patients (85%) were above the age of 40 years. There was a slight male predominance (55%). Ulcerated BCC was the most common gross picture (60%), followed by nodular lesion (30%) and finally the ulcerated nodule (10%). Most of the lesions situated in the high-risk sites (77%) where the nose was the most common site (35%) followed by the periocular area (22%), then periauricular (15%) and finally perioral (5%). No lesion was reported outside the head. The tumor size was less than 2 centimeters in 65% of cases, and from 2-5 centimeters in the lesions' greatest dimension in the rest of cases. Histopathological reclassification revealed that the nodular BCC was the most common (68%) followed by the pigmented nodular (18.75%). The histologic high-risk groups represented (7.5%) about half of them (3.75%) being basosquamous carcinoma. The total incidence for multiple BCC and 2nd primary was 12%. Recurrent BCC represented 8%. All of the recurrent lesions of BCC belonged to the histologic high-risk group. Conclusion: Basal Cell Carcinoma is the most common skin cancer in the 10-year survey. Histopathological diagnosis and classification of BCC cases are essential for the determination of the tumor type and its biological behavior.

Keywords: basal cell carcinoma, high risk, histopathological features, statistical analysis

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6083 Electrohydrodynamic Patterning for Surface Enhanced Raman Scattering for Point-of-Care Diagnostics

Authors: J. J. Rickard, A. Belli, P. Goldberg Oppenheimer

Abstract:

Medical diagnostics, environmental monitoring, homeland security and forensics increasingly demand specific and field-deployable analytical technologies for quick point-of-care diagnostics. Although technological advancements have made optical methods well-suited for miniaturization, a highly-sensitive detection technique for minute sample volumes is required. Raman spectroscopy is a well-known analytical tool, but has very weak signals and hence is unsuitable for trace level analysis. Enhancement via localized optical fields (surface plasmons resonances) on nanoscale metallic materials generates huge signals in surface-enhanced Raman scattering (SERS), enabling single molecule detection. This enhancement can be tuned by manipulation of the surface roughness and architecture at the sub-micron level. Nevertheless, the development and application of SERS has been inhibited by the irreproducibility and complexity of fabrication routes. The ability to generate straightforward, cost-effective, multiplex-able and addressable SERS substrates with high enhancements is of profound interest for SERS-based sensing devices. While most SERS substrates are manufactured by conventional lithographic methods, the development of a cost-effective approach to create nanostructured surfaces is a much sought-after goal in the SERS community. Here, a method is established to create controlled, self-organized, hierarchical nanostructures using electrohydrodynamic (HEHD) instabilities. The created structures are readily fine-tuned, which is an important requirement for optimizing SERS to obtain the highest enhancements. HEHD pattern formation enables the fabrication of multiscale 3D structured arrays as SERS-active platforms. Importantly, each of the HEHD-patterned individual structural units yield a considerable SERS enhancement. This enables each single unit to function as an isolated sensor. Each of the formed structures can be effectively tuned and tailored to provide high SERS enhancement, while arising from different HEHD morphologies. The HEHD fabrication of sub-micrometer architectures is straightforward and robust, providing an elegant route for high-throughput biological and chemical sensing. The superior detection properties and the ability to fabricate SERS substrates on the miniaturized scale, will facilitate the development of advanced and novel opto-fluidic devices, such as portable detection systems, and will offer numerous applications in biomedical diagnostics, forensics, ecological warfare and homeland security.

Keywords: hierarchical electrohydrodynamic patterning, medical diagnostics, point-of care devices, SERS

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6082 Influence of Dopant of Tin (Sn) on the Optoelectronic and Structural Properties of Cadmium Sulfide (CdS) Pallets

Authors: Himanshu Pavagadhi, Maunik Jani, S. M. Vyas, Jaymin Ray, Vimal Patel, Piyush Patel, Jignesh P. Raval

Abstract:

The preparation of pure and Sn-doped cadmium sulfide (CdS) pellets was carried out using a compression technique with a pelletizer. The energy dispersive X-ray (EDX) analysis is used to confirm the purity and stoichiometric ratio of Cd, S, and Sn in the prepared pellets. The surface morphology of the pellets was examined using a scanning electron microscope. Both XRD and Raman scattering spectrum analysis confirmed the doping effect in the CdS pellets. The X-ray diffraction (XRD) analysis confirmed the hexagonal structure and revealed that the grain size decreases with increasing Sn dopant concentration in the parent CdS pellet. The optical properties of the pellets were evaluated by measuring diffuse reflectance using a UV-vis spectrophotometer. The analysis indicated that as the Sn concentration increases in the parent CdS pellet, the optical band gap decreases. This implies that the optical properties of the CdS material are also affected by the Sn dopant.

Keywords: CdS, Sn dopant, UV-Spetrophotometer, XRD

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6081 Quaternized PPO/PSF Anion Exchange Membranes Doped with ZnO-Nanoparticles for Fuel Cell Application

Authors: P. F. Msomi, P. T. Nonjola, P. G. Ndungu, J. Ramontja

Abstract:

In view of the projected global energy demand and increasing levels of greenhouse gases and pollutants issues have inspired an intense search for alternative new energy technologies, which will provide clean, low cost and environmentally friendly solutions to meet the end user requirements. Alkaline anion exchange membrane fuel cells (AAEMFC) have been recognized as ideal candidates for the generation of such clean energy for future stationary and mobile applications due to their many advantages. The key component of the AAEMFC is the anion exchange membrane (AEM). In this report, a series of quaternized poly (2.6 dimethyl – 1.4 phenylene oxide)/ polysulfone (QPPO/PSF) blend anionic exchange membranes (AEM) were successfully fabricated and characterized for alkaline fuel cell application. Zinc Oxide (ZnO) nanoparticles were introduced in the polymer matrix to enhance the intrinsic properties of the AEM. The characteristic properties of the QPPO/PSF and QPPO/PSF-ZnO blend membrane were investigated with X-ray diffraction (XRD), thermogravimetric analysis (TGA) scanning electron microscope (SEM) and contact angle (CA). To confirm successful quaternisation, FT-IR spectroscopy and proton nuclear magnetic resonance (1H NMR) were used. Other properties such as ion exchange capacity (IEC), water uptake, contact angle and ion conductivity (IC) were also undertaken to check if the prepared nanocomposite materials are suitable for fuel cell application. The membrane intrinsic properties were found to be enhanced by the addition of ZnO nanoparticles. The addition of ZnO nanoparticles resulted to a highest IEC of 3.72 mmol/g and a 30-fold IC increase of the nanocomposite due to its lower methanol permeability. The above results indicate that QPPO/PSF-ZnO is a good candidate for AAEMFC application.

Keywords: anion exchange membrane, fuel cell, zinc oxide nanoparticle, nanocomposite

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6080 Hsa-miR-329 Functions as a Tumor Suppressor through Targeting MET in Non-Small Cell Lung Cancer

Authors: Cheng-Cao Sun, Shu-Jun Li, Cuili Yang, Yongyong Xi, Liang Wang, Feng Zhang, De-Jia Li

Abstract:

MicroRNAs (miRNAs) act as key regulators of multiple cancers. Hsa-miR-329 (miR-329) functions as a tumor suppressor in some malignancies. However, its role on lung cancer remains poorly understood. In this study, we investigated the role of miR-329 on the development of lung cancer. The results indicated that miR-329 was decreased in primary lung cancer tissues compared with matched adjacent normal lung tissues and very low levels were found in a non-small cell lung cancer (NSCLC) cell lines. Ectopic expression of miR-329 in lung cancer cell lines substantially repressed cell growth as evidenced by cell viability assay, colony formation assay and BrdU staining, through inhibiting cyclin D1, cyclin D2, and up-regulatiing p57(Kip2) and p21(WAF1/CIP1). In addition, miR-329 promoted NSCLC cell apoptosis, as indicated by up-regulation of key apoptosis gene cleaved caspase-3, and down-regulation of anti-apoptosis gene Bcl2. Moreover, miR-329 inhibited cellular migration and invasiveness through inhibiting matrix metalloproteinases (MMP)-7 and MMP-9. Further, oncogene MET was revealed to be a putative target of miR-329, which was inversely correlated with miR-329 expression. Furthermore, down-regulation of MET by siRNA performed similar effects to over-expression of miR-329. Collectively, our results demonstrated that miR-329 played a pivotal role in lung cancer through inhibiting cell proliferation, migration, invasion, and promoting apoptosis by targeting oncogenic MET.

Keywords: hsa-miRNA-329(miR-329), MET, non-small cell lung cancer (NSCLC), proliferation, apoptosis

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6079 Understanding Childhood Sexual Abuse and Its Association with Psychological Traumatization, Re-Traumatization, and Shame in Adult South Asian Women: A Scoping Review

Authors: Manisha Massey, Mariette Berndsen, Helen McLaren

Abstract:

The existing body of literature concerning the incidence, prevalence, and experiences of childhood sexual abuse (CSA) lacked cultural inclusivity, primarily reflecting Euro-centric perspectives. This study investigated and reviewed the existing literature to understand the experiences of women of color from South Asia, addressing the gap in understanding how culture and diversity impact CSA. While individualist cultures emphasize autonomy, collectivist societies prioritize interdependence. South Asia's diverse intersections, including gender, caste, religion, and class, have intensified child sexual exploitation, challenging assumed homogeneity and safety. Additionally, the power exploitation in the space of abuse and grooming supplementing with the prevalence of honor violence makes disclosures of sexual abuse for children daunting and unsafe in these cultures. This scoping review examined the connection between CSA, psychological trauma, re-traumatization, and shame among adult South Asian women from India, Pakistan, and Bangladesh. Despite distinct borders, these countries share historical, linguistic, and traditional ties. Following PRISMA guidelines, the review employed thematic analysis. Findings underscored cultural factors' influence on CSA incidence, help-seeking barriers, and treatment challenges. The pivotal role of shame (sharam) and honor (izzat) in disclosure and healing processes was highlighted. The study emphasized the need for culturally sensitive interventions while noting limited literature on re-traumatisation. Incorporating a culturally informed perspective, this research aims to decolonize trauma therapy by contributing to the CSA discourse, shedding light on its intricate interaction with trauma, shame, and healing among South Asian women.

Keywords: Childhood sexual abuse, decolonizing psychology, trauma, re-trauma, shame

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6078 Development of a Combustible Gas Detector with Two Sensor Modules to Enable Measuring Range of Low Concentration

Authors: Young Gyu Kim, Sangguk Ahn, Gyoutae Park, Hiesik Kim

Abstract:

In the gas industrial fields, there are many problems to detect extremely small amounts of combustible gas (CH₄) if a conventional semiconductor is used. Those reasons are that measuring is difficult at the low concentration level, the stabilization time is long, and an initial response time is slow. In this study, we propose a method to solve these issues using two specific sensors to overcome the circumstances of temperature and humidity. This idea is to combine a catalytic and a semiconductor type sensor and to utilize every advantage from every sensor’s characteristic. In order to achieve the goal, we reduced fluctuations of a gas sensor for temperature and humidity by applying designed circuits for sensing temperature and humidity. And we induced the best calibration line of gas sensors through adjusting a weight value corresponding to changeable patterns of temperature and humidity after their data are previously acquired and stored. We proposed and developed the gas leak detector using two sensor modules, which is first operated by a semiconductor sensor for measuring small gas quantities and second a catalytic type sensor is detected if measuring range of the first sensor is beyond. We conclusively verified characteristics of sharp sensitivity and fast response time against even at lower gas concentration level through experiments other than a conventional gas sensor. We think that our proposed idea is very useful if another gas leak is developed to enable measuring extremely small quantities of toxic and flammable gases.

Keywords: gas sensor, leak detector, lower concentration, and calibration

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6077 Attributes of Employee Engagement Best Practices: A Guideline for SMEs

Authors: Ghazanfar Bozai, Kanwal Gul

Abstract:

In Pakistan, SMEs are the major source of contribution to the economy, but due to lack of proper HR practices (lack of employee engagement), these fast growing business shut down with in few years of startup. The purpose of this study is to conduct a comprehensive literature survy of the major best practices used for employee engagement globally. This paper could be used as employee engagement best practices guide for SME’s in developing countries. This article is focused on identifying the attributes of employee engagement in different countries/ cultures and organizations. It will provide a summary of employee engagement models used globally and how SMEs could pick suitable attributes of employee engagement as per their structural culture. This article will add valuable literature on employee engagement in developing countries for new startups and small, medium business.

Keywords: attributes, employee engagement, human resources practices, small medium enterprises

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6076 Wastewater Treatment Sludge as a Potential Source of Heavy Metal Contamination in Livestock

Authors: Glynn K. Pindihama, Rabelani Mudzielwana, Ndamulelo Lilimu

Abstract:

Wastewater treatment effluents, particularly sludges, are known to be potential sources of heavy metal contamination in the environment, depending on how the sludge is managed. Maintenance of wastewater treatment infrastructure in developing countries such as South Africa has become an issue of grave concern, with many wastewater treatment facilities in dilapidating states. Among the problems is the vandalism of the periphery fence to many wastewater treatment facilities, resulting in livestock, such as cows from neighboring villages, grazing within the facilities. This raises human health risks since dried sludge from the treatment plants is usually spread on the grass around the plant, resulting in heavy metal contamination. Animal products such as meat and milk from these cows thus become an indirect route to heavy metals to humans. This study assessed heavy metals in sludges from 3 wastewater treatment plants in Limpopo Province of South Africa. In addition, cow dung and sludge liquors were collected from these plants and evaluated for their heavy metal content. The sludge and cow dung were microwave-digested using the aqua-regia method, and all samples were analyzed for heavy metals using ICP-OES. The loadings of heavy metals in the sludge were in the order Cu>Zn>Ni>Cr>Cd>As>Hg. In cow dung, the heavy metals were in the order Fe>Cu>Mn>Zn>Cr>Pb>Co>Cd. The levels of Zn and Cu in the sludge liquors where the animals were observed drinking were, in some cases, above the permissible limit for livestock consumption. Principal component and correlation analysis are yet to be done to determine if there is a correlation between the heavy metals in the cow dung and sludge and sludge liquors.

Keywords: cow dung, heavy metals, sludge, wastewater treatment plants, sludge.

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6075 Simulation and Characterization of Compact Magnetic Proton Recoil Spectrometer for Fast Neutron Spectra Measurements

Authors: Xingyu Peng, Qingyuan Hu, Xuebin Zhu, Xi Yuan

Abstract:

Neutron spectrometry has contributed much to the development of nuclear physics since 1932 and has also become an importance tool in several other fields, notably nuclear technology, fusion plasma diagnostics and radiation protection. Compared with neutron fluxes, neutron spectra can provide more detailed information on the internal physical process of neutron sources, such as fast neutron reactors, fusion plasma, fission-fusion hybrid reactors, and so on. However, high performance neutron spectrometer is not so commonly available as it requires the use of large and complex instrumentation. This work describes the development and characterization of a compact magnetic proton recoil (MPR) spectrometer for high-resolution measurements of fast neutron spectra. The compact MPR spectrometer is featured by its large recoil angle, small size permanent analysis magnet, short beam transport line and dual-purpose detector array for both steady state and pulsed neutron spectra measurement. A 3-dimensional electromagnetic particle transport code is developed to simulate the response function of the spectrometer. Simulation results illustrate that the performance of the spectrometer is mainly determined by n-p recoil foil and proton apertures, and an overall energy resolution of 3% is achieved for 14 MeV neutrons. Dedicated experiments using alpha source and mono-energetic neutron beam are employed to verify the simulated response function of the compact MPR spectrometer. These experimental results show a good agreement with the simulated ones, which indicates that the simulation code possesses good accuracy and reliability. The compact MPR spectrometer described in this work is a valuable tool for fast neutron spectra measurements for the fission or fusion devices.

Keywords: neutron spectrometry, magnetic proton recoil spectrometer, neutron spectra, fast neutron

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6074 Large-scale Foraging Behaviour of Free-ranging Goats: Influence of Herd Size, Landscape Quality and Season

Authors: Manqhai Kraai, Adrian M. Shrader, Peter F. Scogings

Abstract:

For animals living in herds, competition between group members increases as herd size increases. The intensity of this competition is likely greater across poor quality landscapes and during the dry season. In contrast to wild herbivores, herd size in domestic livestock is determined by their owners. This then raises the question, how do domestic livestock, like goats, reduce competition for food within these defined herds? To explore this question, large-scale foraging behaviour of both small (12 to 28 individuals) and large (42 to 83 individuals) herds of free-ranging goats were recorded in Tugela Ferry, KwaZulu-Natal, South Africa. The study was conducted on three different landscapes that varied in both food quality and availability, during the wet and dry seasons of 2013-2014. The goats were housed in kraals overnight and let out in the mornings to forage unattended. Thus, foraging decisions were made by the goats and not by herders. The large-scale foraging behaviours focussed on included, (i) total distance travelled by goats while foraging, (ii) distance travelled before starting to feed, (iii) travel speed, and (iv) feeding duration. This was done using Garmin Foretrex 401 GPS devices harnessed to two goats per herd. Irrespective of season, there was no difference in the total distance travelled by the different sized herds across the different quality landscapes. However, both small and large herds started feeding farther from the kraal in the dry compared to the wet season. Despite this, there was no significant seasonal difference in total amount of time the herds spent feeding across the different landscapes. Finally, both small and large herds increased their travel speed across all the landscapes in the dry season, but large herds travelled faster than small herds. This increase was likely to maximise the time that large herds could spend feeding in good areas. Ultimately, these results indicate that both small and large herds were affected by declines in food quality and quantity during the dry season. However, as large herds made greater behavioural adjustments compared to smaller herds (i.e., feeding farther away from the kraal and travelling faster), it appeared that they were more affected by the seasonal increases in intra-herd competition.

Keywords: distance, feeding duration, food availability, food quality, travel speed

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6073 Factors Influencing Milk Yield, Quality, and Revenue of Dairy Farms in Southern Vietnam

Authors: Ngoc-Hieu Vu

Abstract:

Dairy production in Vietnam is a relatively new agricultural activity and milk production increased remarkably in recent years. Smallholders are still the main drivers for this development, especially in the southern part of the country. However, information on the farming practices is very limited. Therefore, this study aimed to determine factors influencing milk yield and quality (milk fat, total solids, solids-not-fat, total number of bacteria, and somatic cell count) and revenue of dairy farms in Southern Vietnam. The collection of data was at the farm level; individual animal records were unavailable. The 539 studied farms were located in the provinces Lam Dong (N=111 farms), Binh Duong (N=69 farms), Long An (N=174 farms), and Ho Chi Minh city (N=185 farms). The dataset included 9221 monthly test-day records of the farms from January 2013 to May 2015. Seasons were defined as rainy and dry. Farms sizes were classified as small (< 10 milking cows), medium (10 to 19 milking cows) and large (≥ 20 milking cows). The model for each trait contained year-season and farm region-farm size as subclass fixed effects, and individual farm and residual as random effects. Results showed that year-season, region, and farm size were determining sources of variation affecting all studied traits. Milk yield was higher in dry than in rainy seasons (P < 0.05), while it tended to increase from years 2013 to 2015. Large farms had higher yields (445.6 kg/cow) than small (396.7 kg/cow) and medium (428.0 kg/cow) farms (P < 0.05). Small farms, in contrast, were superior to large farms in terms of milk fat, total solids, solids-not-fat, total number of bacteria, and somatic cell count than large farms (P < 0.05). Revenue per cow was higher in large compared with medium and small farms. In conclusion, large farms achieved higher milk yields and revenues per cow, while small farms were superior in milk quality. Overall, milk yields were low and better training, financial support and marketing opportunities for farmers are needed to improve dairy production and increase farm revenues in Southern Vietnam.

Keywords: farm size, milk yield and quality, season, Southern Vietnam

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6072 Assessment of Population Trends of Birds at Taunsa Barrage Wildlife Sanctuary, Pakistan

Authors: Fehmeada Bibi, Shafqat Nawaz Qaisrani, Masood Akhtar, Zulfiqar Ali

Abstract:

Population trends learning is an important tool for conservation programs in rare as well as in common species of birds. A study was conducted to assess annual decline in species of birds and to identify the causes of this decline at Taunsa Barrage wildlife Sanctuary, Punjab, Pakistan. Data were collected by direct census method during wintering and breeding periods (2001 to 2002 and 2008 to 2011). The results indicated an increasing trend in 157, whereas a decreasing trend in 14 species of birds. Among the species with declining trend, there was a 92% decrease in White-backed Vulture (Gyps bengalensis), 60% in Greater Painted Snipe (Rostratula benghalensis), 57% in Garganey (Anas querquedula), Pallas’s Fish Eagle and Long-legged Buzzard (Buteo rufinus) 50% each, 41% in Grey Heron (Ardea cinerea), 39% in Little Cormorant (Phalacrocorax niger), 37% in Gadwall (Anas strepera), 33% in Marsh Harrier (Circus aeruginosus), 30% in Black Drongo (Dicrurus macrocercus) and 26% in Red-crested Pochard (Netta rufina) population. Habitat exploitation, hunting and grazing were found the main causes of this decline. In conclusion, conservation and management of the study area is foremost to interests of declining bird population. It is suggested, therefore, to take immediate steps for the protection of the sanctuary to conserve the declining population of birds.

Keywords: population trends, wildlife sanctuary, bird, habitat exploitation

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6071 Lyapunov and Input-to-State Stability of Stochastic Differential Equations

Authors: Arcady Ponosov, Ramazan Kadiev

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Input-to-State Stability (ISS) is widely used in deterministic control theory but less known in the stochastic case. Roughly speaking, the theory explains when small perturbations of the right-hand sides of the system on the entire semiaxis cause only small changes in the solutions of the system, again on the entire semiaxis. This property is crucial in many applications. In the report, we explain how to define and study ISS for systems of linear stochastic differential equations with or without delays. The central result connects ISS with the property of Lyapunov stability. This relationship is well-known in the deterministic setting, but its stochastic version is new. As an application, a method of studying asymptotic Lyapunov stability for stochastic delay equations is described and justified. Several examples are provided that confirm the efficiency and simplicity of the framework.

Keywords: asymptotic stability, delay equations, operator methods, stochastic perturbations

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6070 Development of a Cost Effective Two Wheel Tractor Mounted Mobile Maize Sheller for Small Farmers in Bangladesh

Authors: M. Israil Hossain, T. P. Tiwari, Ashrafuzzaman Gulandaz, Nusrat Jahan

Abstract:

Two-wheel tractor (power tiller) is a common tillage tool in Bangladesh agriculture for easy access in fragmented land with affordable price of small farmers. Traditional maize sheller needs to be carried from place to place by hooking with two-wheel tractor (2WT) and set up again for shelling operation which takes longer time for preparation of maize shelling. The mobile maize sheller eliminates the transportation problem and can start shelling operation instantly any place as it is attached together with 2WT. It is counterclockwise rotating cylinder, axial flow type sheller, and grain separated with a frictional force between spike tooth and concave. The maize sheller is attached with nuts and bolts in front of the engine base of 2WT. The operating power of the sheller comes from the fly wheel of the engine of the tractor through ‘V” belt pulley arrangement. The average shelling capacity of the mobile sheller is 2.0 t/hr, broken kernel 2.2%, and shelling efficiency 97%. The average maize shelling cost is Tk. 0.22/kg and traditional custom hire rate is Tk.1.0/kg, respectively (1 US$=Tk.78.0). The service provider of the 2WT can transport the mobile maize sheller long distance in operator’s seating position. The manufacturers started the fabrication of mobile maize sheller. This mobile maize sheller is also compatible for the other countries where 2WT is available for farming operation.

Keywords: cost effective, mobile maize sheller, maize shelling capacity, small farmers, two wheel tractor

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6069 A Spatio-Temporal Analysis and Change Detection of Wetlands in Diamond Harbour, West Bengal, India Using Normalized Difference Water Index

Authors: Lopita Pal, Suresh V. Madha

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Wetlands are areas of marsh, fen, peat land or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres. The rapidly expanding human population, large scale changes in land use/land cover, burgeoning development projects and improper use of watersheds all has caused a substantial decline of wetland resources in the world. Major degradations have been impacted from agricultural, industrial and urban developments leading to various types of pollutions and hydrological perturbations. Regular fishing activities and unsustainable grazing of animals are degrading the wetlands in a slow pace. The paper focuses on the spatio-temporal change detection of the area of the water body and the main cause of this depletion. The total area under study (22°19’87’’ N, 88°20’23’’ E) is a wetland region in West Bengal of 213 sq.km. The procedure used is the Normalized Difference Water Index (NDWI) from multi-spectral imagery and Landsat to detect the presence of surface water, and the datasets have been compared of the years 2016, 2006 and 1996. The result shows a sharp decline in the area of water body due to a rapid increase in the agricultural practices and the growing urbanization.

Keywords: spatio-temporal change, NDWI, urbanization, wetland

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6068 Enhancing Wheat Productivity for Small-Scale Farmers in the Northern State of Sudan through Developing a Local Made Seed Cleaner and Different Seeding Methods

Authors: Yasir Hassan Satti Mohammed

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The wheat cleaner was designed, manufactured, and tested in the workshop of the department of agricultural engineering, faculty of agricultural sciences, university of Dongola, the northern state of Sudan, for the purpose of enhancing productivity for small-scale-farmers who used to plant their saved wheat seeds every season with all risk of weed infestation and low viability. A one-season field experiment was then conducted according to the Randomized Complete Block Design (RCBD) experimental design in the demonstration farm of Dongola research station using clean seeds and unclean seeds of a local wheat variety (Imam); two different planting methods were also adopted in the experiment. One is the traditional seed drilling within the recommended seed rate (50 kg.feddan⁻¹), whereas the other was the precision seeding method using half of the recommended seed rate (25 kg.feddan⁻¹). The effect of seed type and planting method on field parameters were investigated, and the data was then analyzed using a computer application SAS system version 9.3. The results revealed significant (P ≥ 0.05) and highly significant (P ≥ 0.01) differences between treatments. The precision seeding method with clean seeds increased the number of kernels per spike (KS), tillers per plant (TPP), one thousand kernels mass (TKM), the biomass of wheat (BWT), and total yield (TOY), whereas weeds per area (WSM), the biomass of weeds (BWD) and weight of weed seeds were apparently decreased compared to seed drilling with unclean seed. Wheat seed cleaner could be of great benefit for small-scale wheat farmers in Sudan who cannot afford the cleaned seeds commercially provided by the local government.

Keywords: wheat cleaner, precision seeding, seed drilling method, small-scale farmers

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6067 Predictors of Recent Work-Related Injury in a Rapidly Developing Country: Results from a Worker Survey in Qatar

Authors: Ruben Peralta, Sam Thomas, Nazia Hirani, Ayman El-Menyar, Hassan Al-Thani, Mohammed Al-Thani, Mohammed Al-Hajjaj, Rafael Consunji

Abstract:

Moderate to severe work-related injuries [WRI's] are a leading cause of trauma admission in Qatar but information on risk factors for their incidence are lacking. This study aims to document and analyze the predictive characteristics for WRI to inform the creation of targeted interventions to improve worker safety in Qatar. This study was conducted as part of the NPRP grant # 7 - 1120 - 3 - 288, titled "A Unified Registry for Occupational Injury Prevention in Qatar”. 266 workers were interviewed using a standard questionnaire, during ‘World Day for Safety and Health at Work’, a Ministry of Public Health event, none refused interview. Nurses and doctors from the Hamad Trauma Center conducted the interviews. Questions were translated into the worker’s native language when it was deemed necessary. Standard information on epidemiologic characteristics and incidence of work-related injury were collected and compared between nationalities and those injured versus those not injured. 262 males and 4 females were interviewed. 17 [6.4%] reported a WRI in the last 24 months. More than half of the injured worked in construction [59%] followed by water supply [11.8%]. Factors significantly associated with recent injury were: Working for a company with > 500 employees and speaking Hindi. Protective characteristics included: Being from the Philippines or Sri Lanka, speaking Arabic, working in healthcare, an office or trading and company size between 100-500 employees. Years of schooling and working in Qatar were not predictive factor for WRI. The findings from this survey should guide future research that will better define worker populations at an increased risk for WRI and inform recruiters and sending countries. A focus on worker language skills, interventions in the construction industry and occupational safety in large companies is needed.

Keywords: occupational injury, prevention, safety, trauma, work related injury

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6066 Automatic Registration of Rail Profile Based Local Maximum Curvature Entropy

Authors: Hao Wang, Shengchun Wang, Weidong Wang

Abstract:

On the influence of train vibration and environmental noise on the measurement of track wear, we proposed a method for automatic extraction of circular arc on the inner or outer side of the rail waist and achieved the high-precision registration of rail profile. Firstly, a polynomial fitting method based on truncated residual histogram was proposed to find the optimal fitting curve of the profile and reduce the influence of noise on profile curve fitting. Then, based on the curvature distribution characteristics of the fitting curve, the interval search algorithm based on dynamic window’s maximum curvature entropy was proposed to realize the automatic segmentation of small circular arc. At last, we fit two circle centers as matching reference points based on small circular arcs on both sides and realized the alignment from the measured profile to the standard designed profile. The static experimental results show that the mean and standard deviation of the method are controlled within 0.01mm with small measurement errors and high repeatability. The dynamic test also verified the repeatability of the method in the train-running environment, and the dynamic measurement deviation of rail wear is within 0.2mm with high repeatability.

Keywords: curvature entropy, profile registration, rail wear, structured light, train-running

Procedia PDF Downloads 254
6065 Ophthalmic Self-Medication Practices and Associated Factors among Adult Ophthalmic Patients

Authors: Sarah Saad Alamer, Shujon Mohammed Alazzam, Amjad Khater Alanazi, Mohamed Ahmed Sankari, Jana Sameer Sendy, Saleh Al-Khaldi, Khaled Allam, Amani Badawi

Abstract:

Background: Self-medication is defined as the selection of medicines by individuals to treat self-diagnosed. There are a lot of concerns about the safety of long-term use of nonprescription ophthalmic drugs, which may lead to a variety of serious ocular complications. Topical steroids can produce severe eye-threatening complications, including the elevation of intraocular pressure (IOP) with possible development of glaucoma and infrequent optic nerve damage. In recent times, many OTC ophthalmic preparations have been possible without a prescription. Objective: In our study, we aimed to determine the prevalence of self-medication ocular topical steroid practice and associated factors among adult ophthalmic patients attending King Saud medical city. Methods: This study was conducted as a cross-sectional study, targeting participants aged 18 years old or above who had used topical steroids eye drops to determine the prevalence of self-medication ocular topical steroid practice and associated factors among adult patients attending ophthalmology clinic in King Saud Medical City (KSMC) in the central region. Results: A total of 308 responses, 92(29.8%) were using ocular topical, 58(18.8%) with prescription, 5(1.6%) without prescription, 29(9.4%) with and without prescription while 216(70.1%) did not use it. The frequency of using ocular topical steroids without a prescription among participants was 11(12%) once and 33 (35%) many times. 26(28.3%) were having complication, mostly 11(12.4%) eye infection, 8(9%) Glaucoma, 6 (6.7%) Cataracts. Reasons for self-medication ocular topical steroid practice among participants were 14 (15.2%) repeated symptoms, 11(15.2%) had heard an advice from a friend, 11 (15.2%) thought they had enough knowledge. Conclusion: Our study reveals that, even though detecting a high level of knowledge and acceptable practices and attitudes among participants, the incidence of self-medication with steroid eye drops was observed. This practice is mainly due to participants having repeated symptoms and thinking they have enough knowledge. Increasing the education level of patients on self-medication steroid eye drops practice and it is associated complications would help reduce the incidence of self-medication steroid eye drops practice.

Keywords: self-medication, ophthalmic medicine, steroid eye drop, over the counter

Procedia PDF Downloads 80
6064 Pastoralist Transhumance and Conflict along the Nigeria-niger Borderlands: Towards New Perspective for Effective Border Management in Africa

Authors: Abubakar Samaila

Abstract:

Pastoralism has been an old practice in the Sahel region of west Africa. In recent years, pastoralists in Nigeria have increasingly been migrating on seasonal transhumance southward from the neighboring countries, especially Niger Republic, in search of better grazing conditions due to mainly, climate change. This has increased pressure on farm lands which instigate farmer-herder conflicts. These conflicts occur mainly between farmers and pastoralists but also between pastoralist groups themselves. However, there has been a shift in these conflicts recently to involve traditional institutions and, in some cases, the local authorities along the borderlands. The involvement of local institutions in the conflict has created an incentive to local actors, particularly pastoralcommunity-based groups, in responding to these violent threats. As pastoralists are mobile, these conflicts became difficult to contain and, thus, spill across borders. Consequently, the conflict has now transformed into an urbanized regional conflicts that involve some major cities along the Nigeria-Niger borderlands; Sokoto, Zamfara, and Katsina on the Nigerian side andDosso, Tahoa andMaradi in Niger republic. These areas are now experiencing unprecedented growing wave of violence that have become complex and escalates into a hydra-social conflict. The aim of this research is to investigate how the fluidities of Nigeria-Niger borderland intensified armed conflicts between the local pastoral organizations and sedentary populationspreading to some urban cities along the borderlands. The paper further suggests alternative approaches towards addressing the perennial crisis in African borderlands.

Keywords: pastoralism, climate change, conflict, nigeria, niger, borderlands

Procedia PDF Downloads 85
6063 The Correlation between Clostridium Difficile Infection and Bronchial Lung Cancer Occurrence

Authors: Molnar Catalina, Lexi Frankel, Amalia Ardeljan, Enoch Kim, Marissa Dallara, Omar Rashid

Abstract:

Introduction: Clostridium difficile (C. diff) is a toxin-producing bacteria that can cause diarrhea and colitis. U.S. Center for Disease Control and Prevention revealed that C. difficile infection (CDI) has increased from 31 cases per 100,000 persons per year in 1996 to 61 per 100,000 in 2003. Approximately 500,000 cases per year occur in the United States. After exposure, the bacteria colonize the colon, where it adheres to the intestinal epithelium where it produces two toxins: TcdA and TcdB. TcdA affects the intestinal epithelium, causing fluid secretion, inflammation, and tissue necrosis, while TcdB acts as a cytotoxin purpose of this study was to evaluate the association between C diff infection and bronchial lung cancer development. Methods: Using ICD- 9 and ICD-10 codes, the data was provided by a Health Insurance Portability and Accountability Act (HIPAA) compliant national database to assess the patients infected with C diff as opposed to the non-infected patients. The Holy Cross Health, Fort Lauderdale, granted access to the database for the purpose of academic research. Patients were matched for age and Charlson Comorbidity Index (CCI). Standard statistical methods were used. Results: Bronchial lung cancer occurrence in the population not infected with C diff infection was 4741, as opposed to the population infected with C. diff, where 2039 cases of lung cancer were observed. The difference was statistically significant (p-value < 2.2x10^e-16), which reveals that C diff might be protective against bronchial lung cancer. The data was then matched by treatment to create to minimize the effect of treatment bias. Bronchial cancer incidence was 422 and 861 in infected vs. non-infected (p-value of < 2.2x10^e-16), which once more indicates that C diff infection could be beneficial in diminishing bronchial cancer development. Conclusion: This retrospective study conveys a statistical correlation between C diff infection and decreased incidence of lung bronchial cancer. Further studies are needed to comprehend the protective mechanisms of C. Diff infection on lung cancer.

Keywords: C. diff, lung cancer, protective, microbiology

Procedia PDF Downloads 230
6062 A Model of the Universe without Expansion of Space

Authors: Jia-Chao Wang

Abstract:

A model of the universe without invoking space expansion is proposed to explain the observed redshift-distance relation and the cosmic microwave background radiation (CMB). The main hypothesized feature of the model is that photons traveling in space interact with the CMB photon gas. This interaction causes the photons to gradually lose energy through dissipation and, therefore, experience redshift. The interaction also causes some of the photons to be scattered off their track toward an observer and, therefore, results in beam intensity attenuation. As observed, the CMB exists everywhere in space and its photon density is relatively high (about 410 per cm³). The small average energy of the CMB photons (about 6.3×10⁻⁴ eV) can reduce the energies of traveling photons gradually and will not alter their momenta drastically as in, for example, Compton scattering, to totally blur the images of distant objects. An object moving through a thermalized photon gas, such as the CMB, experiences a drag. The cause is that the object sees a blue shifted photon gas along the direction of motion and a redshifted one in the opposite direction. An example of this effect can be the observed CMB dipole: The earth travels at about 368 km/s (600 km/s) relative to the CMB. In the all-sky map from the COBE satellite, radiation in the Earth's direction of motion appears 0.35 mK hotter than the average temperature, 2.725 K, while radiation on the opposite side of the sky is 0.35 mK colder. The pressure of a thermalized photon gas is given by Pγ = Eγ/3 = αT⁴/3, where Eγ is the energy density of the photon gas and α is the Stefan-Boltzmann constant. The observed CMB dipole, therefore, implies a pressure difference between the two sides of the earth and results in a CMB drag on the earth. By plugging in suitable estimates of quantities involved, such as the cross section of the earth and the temperatures on the two sides, this drag can be estimated to be tiny. But for a photon traveling at the speed of light, 300,000 km/s, the drag can be significant. In the present model, for the dissipation part, it is assumed that a photon traveling from a distant object toward an observer has an effective interaction cross section pushing against the pressure of the CMB photon gas. For the attenuation part, the coefficient of the typical attenuation equation is used as a parameter. The values of these two parameters are determined by fitting the 748 µ vs. z data points compiled from 643 supernova and 105 γ-ray burst observations with z values up to 8.1. The fit is as good as that obtained from the lambda cold dark matter (ΛCDM) model using online cosmological calculators and Planck 2015 results. The model can be used to interpret Hubble's constant, Olbers' paradox, the origin and blackbody nature of the CMB radiation, the broadening of supernova light curves, and the size of the observable universe.

Keywords: CMB as the lowest energy state, model of the universe, origin of CMB in a static universe, photon-CMB photon gas interaction

Procedia PDF Downloads 129
6061 Passenger Movement Pattern during Ship Evacuation Considering the Combined Effect of Ship Heeling and Trim

Authors: Jinlu Sun, Shouxiang Lu, Siuming Lo

Abstract:

Large passenger ship, especially luxury cruise, is one of the most prevalent means of marine transportation and tourism nowadays. In case of an accident, an effective evacuation would be the ultimate way to minimize the consequence. Ship heeling and trim has a considerable influence on passenger walking speed and posture during ship evacuation. To investigate passenger movement pattern under the combined effect of ship heeling and trim, a ship corridor simulator was developed. Both fast and freely individual walking experiments by male and female experimental subjects under heeling and trim conditions were conducted and recorded therein. It is found that routes of experimental subjects would change due to the heeling and trim angles, although they always walk along the right side because of cultural factors. Experimental subjects would also change their posture to adapt the combined heeling and trim conditions, such as leaning forward, adopting larger arm swaying, shorter and more frequent steps. While for individual walking speed, the speed would decrease with the increasing heeling and trim angles. But the maximum individual walking speed is achieved at heeling angle of 0° with trim angle ranging from -15° to -5 °, instead of on level ground, which may be attributable to the effect of the gravitational acceleration. Female is approximately 10% slower than male due to the discrepancy in physical quality. Besides, individual walking speed shows similar trends in both fast and freely walking modes, and the speed value in freely walking mode is about 78% of that in fast walking mode under each experimental condition. Furthermore, to designate the movement pattern of passengers in heeling and trim conditions, a model of the walking speed reduction was proposed. This work would provide guidance on the development of evacuation models and the design of evacuation facilities on board.

Keywords: evacuation, heeling, individual walking speed, ship corridor simulator, trim

Procedia PDF Downloads 249
6060 Comparing the Motion of Solar System with Water Droplet Motion to Predict the Future of Solar System

Authors: Areena Bhatti

Abstract:

The geometric arrangement of planet and moon is the result of a self-organizing system. In our solar system, the planets and moons are constantly orbiting around the sun. The aim of this theory is to compare the motion of a solar system with the motion of water droplet when poured into a water body. The basic methodology is to compare both motions to know how they are related to each other. The difference between both systems will be that one is extremely fast, and the other is extremely slow. The role of this theory is that by looking at the fast system we can conclude how slow the system will get to an end. Just like ripples are formed around water droplet that move away from the droplet and water droplet forming those ripples become small in size will tell us how solar system will behave in the same way. So it is concluded that large and small systems can work under the same process but with different motions of time, and motion of the solar system is the slowest form of water droplet motion.

Keywords: motion, water, sun, time

Procedia PDF Downloads 140
6059 Securing Land Rights for Food Security in Africa: An Appraisal of Links Between Smallholders’ Land Rights and the Right to Adequate Food in Ethiopia

Authors: Husen Ahmed Tura

Abstract:

There are strong links between secure land rights and food security in Africa. However, as land is owned by governments, land users do not have adequate legislative protection. This article explores normative and implementation gaps in relation to small-scale farmers’ land rights under the Ethiopia’s law. It finds that the law facilitates eviction of small-scale farmers and indigenous peoples from their land without adequate alternative means of livelihood. It argues that as access to land and other natural resources is strongly linked to the right to adequate food, Ethiopia should reform its land laws in the light of its legal obligations under international human rights law to respect, protect and fulfill the right to adequate food and ensure freedom from hunger.

Keywords: smallholder, secure land rights , food security, right to food, land grabbing, forced evictions

Procedia PDF Downloads 302
6058 Investigation of Boll Properties on Cotton Picker Machine Performance

Authors: Shahram Nowrouzieh, Abbas Rezaei Asl, Mohamad Ali Jafari

Abstract:

Cotton, as a strategic crop, plays an important role in providing human food and clothing need, because of its oil, protein, and fiber. Iran has been one of the largest cotton producers in the world in the past, but unfortunately, for economic reasons, its production is reduced now. One of the ways to reduce the cost of cotton production is to expand the mechanization of cotton harvesting. Iranian farmers do not accept the function of cotton harvesters. One reason for this lack of acceptance of cotton harvesting machines is the number of field losses on these machines. So, the majority of cotton fields are harvested by hand. Although the correct setting of the harvesting machine is very important in the cotton losses, the morphological properties of the cotton plant also affect the performance of cotton harvesters. In this study, the effect of some cotton morphological properties such as the height of the cotton plant, number, and length of sympodial and monopodial branches, boll dimensions, boll weight, number of carpels and bracts angle were evaluated on the performance of cotton picker. In this research, the efficiency of John Deere 9920 spindle Cotton picker is investigated on five different Iranian cotton cultivars. The results indicate that there was a significant difference between the five cultivars in terms of machine harvest efficiency. Golestan cultivar showed the best cotton harvester performance with an average of 87.6% of total harvestable seed cotton and Khorshid cultivar had the least cotton harvester performance. The principal component analysis showed that, at 50.76% probability, the cotton picker efficiency is affected by the bracts angle positively and by boll dimensions, the number of carpels and the height of cotton plants negatively. The seed cotton remains (in the plant and on the ground) after harvester in PCA scatter plot were in the same zone with boll dimensions and several carpels.

Keywords: cotton, bract, harvester, carpel

Procedia PDF Downloads 132
6057 Improvement of Spray Retention on Barley

Authors: Hassina Hafida Boukhalfa, Mohamed Belhamra

Abstract:

Adjuvants contribute to change the types of impact and thus the amount of spray retained by the leaves of the treated plant. We have performed tests of retention on barley plants on BBCH 12 stage and small pieces of barley leaves at the same stage of growth. Spraying was done in three ways: water without adjuvant, water with Break-Thru® S240 and water with Li700®. The three slurries of fluorescein contained in an amount of 0.2 g/l. Fluorescein retained by the leaves in both cases is then measured by a spectrofluoremeter. The retention tests on whole plants show that it is tripled by the first adjuvant and doubled by the second. By cons on small pieces of barley leaves, the amount was increased by the use of surfactants but not to the same scale. This study concluded that the use of adjuvants in spray pesticides may increase the amount of retention as a function of leaf area and the type of adjuvant.

Keywords: Barley, adjuvant, spray retention, fluorometry

Procedia PDF Downloads 295
6056 Application of Adaptive Neural Network Algorithms for Determination of Salt Composition of Waters Using Laser Spectroscopy

Authors: Tatiana A. Dolenko, Sergey A. Burikov, Alexander O. Efitorov, Sergey A. Dolenko

Abstract:

In this study, a comparative analysis of the approaches associated with the use of neural network algorithms for effective solution of a complex inverse problem – the problem of identifying and determining the individual concentrations of inorganic salts in multicomponent aqueous solutions by the spectra of Raman scattering of light – is performed. It is shown that application of artificial neural networks provides the average accuracy of determination of concentration of each salt no worse than 0.025 M. The results of comparative analysis of input data compression methods are presented. It is demonstrated that use of uniform aggregation of input features allows decreasing the error of determination of individual concentrations of components by 16-18% on the average.

Keywords: inverse problems, multi-component solutions, neural networks, Raman spectroscopy

Procedia PDF Downloads 523