Search results for: unknown input observer
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3124

Search results for: unknown input observer

2074 The Admitting Hemogram as a Predictor for Severity and in-Hospital Mortality in Acute Pancreatitis

Authors: Florge Francis A. Sy

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Acute pancreatitis (AP) is an inflammatory condition of the pancreas with local and systemic complications. Severe acute pancreatitis (SAP) has a higher mortality rate. Laboratory parameters like the neutrophil-to-lymphocyte ratio (NLR), red cell distribution width (RDW), and mean platelet volume (MPV) have been associated with SAP but with conflicting results. This study aims to determine the predictive value of these parameters on the severity and in-hospital mortality of AP. This retrospective, cross-sectional study was done in a private hospital in Cebu City, Philippines. One-hundred five patients were classified according to severity based on the modified Marshall scoring. The admitting hemogram, including the NLR, RDW, and MPV, was obtained from the complete blood count (CBC). Cut-off values for severity and in-hospital mortality were derived from the ROC. Association between NLR, RDW, and MPV with SAP and mortality were determined with a p-value of < 0.05 considered significant. The mean age for AP was 47.6 years, with 50.5% being male. Most had an unknown cause (49.5%), followed by a biliary cause (37.1%). Of the 105 patients, 23 patients had SAP, and 4 died. Older age, longer in-hospital duration, congestive heart failure, elevated creatinine, urea nitrogen, and white blood cell count were seen in SAP. The NLR was associated with in-hospital mortality using a cut-off of > 10.6 (OR 1.133, 95% CI, p-value 0.003) with 100% sensitivity, 70.3% specificity, 11.76% PPV and 100% NPV (AUC 0.855). The NLR was not associated with SAP. The RDW and MPV were not associated with SAP and mortality. The admitting NLR is, therefore, an easily accessible parameter that can predict in-hospital mortality in acute pancreatitis. Although the present study did not show an association of NLR with SAP nor RDW and MPV with both SAP and mortality, further studies are suggested to establish their clinical value.

Keywords: acute pancreatitis, mean platelet volume, neutrophil-lymphocyte ratio, red cell distribution width

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2073 Sexual Risk Behaviours among Patients Living with HIV/AIDS in Douala in 2012

Authors: Etienne Sugewe

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Purpose: The establishment of a positive HIV serologic status of an individual could have been an inhibitory factor to prevent risk behaviours in people living with HIV/AIDS. We conducted a cross-sectional study in order to assess the prevalence and predictors of risk behaviors among HIV-positive people in Douala-Cameroon. Methods: We used pre-checked questionnaires to systematically collect data from four HIV treatment centers in Douala. This was done to some of them during the distribution of drugs and to others during their classical rendezvous between the months of May and July 2012. The Chi-Square and Student t-test were used for cross tabulation of variables; multiple regression analysis was performed to identify predictors of risky sexual behaviours. Results: Of the 330 persons interviewed, sixty percent were reported to have had sexual intercourse after the diagnosis of HIV. We obtained 37% HIV-positive partners, and 63% had HIV- negative partners or partners with unknown status. Among our patients, 45% of the subjects with regular partners reported to have had anal or vaginal sex. Those whose score on the knowledge about HIV/AIDS was < 50% and where 90% of them were less susceptible to the condom during intercourse (p: 0.01). About 74% of patients on ARV were less susceptible to the use of condoms during sexual intercourse (p: 0.03). Conclusion: Risk sexual behaviours among people living with HIV/AIDS are common and potentially expose their partners. For HIV-positive partners, these habits pose a real risk of suprainfection by other strains of HIV. The need to increase awareness and education among people living with HIV is therefore highly recommended.

Keywords: HIV/AIDS, behaviours, HIV positive, Douala, 2012

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2072 Facial Behavior Modifications Following the Diffusion of the Use of Protective Masks Due to COVID-19

Authors: Andreas Aceranti, Simonetta Vernocchi, Marco Colorato, Daniel Zaccariello

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Our study explores the usefulness of implementing facial expression recognition capabilities and using the Facial Action Coding System (FACS) in contexts where the other person is wearing a mask. In the communication process, the subjects use a plurality of distinct and autonomous reporting systems. Among them, the system of mimicking facial movements is worthy of attention. Basic emotion theorists have identified the existence of specific and universal patterns of facial expressions related to seven basic emotions -anger, disgust, contempt, fear, sadness, surprise, and happiness- that would distinguish one emotion from another. However, due to the COVID-19 pandemic, we have come up against the problem of having the lower half of the face covered and, therefore, not investigable due to the masks. Facial-emotional behavior is a good starting point for understanding: (1) the affective state (such as emotions), (2) cognitive activity (perplexity, concentration, boredom), (3) temperament and personality traits (hostility, sociability, shyness), (4) psychopathology (such as diagnostic information relevant to depression, mania, schizophrenia, and less severe disorders), (5) psychopathological processes that occur during social interactions patient and analyst. There are numerous methods to measure facial movements resulting from the action of muscles, see for example, the measurement of visible facial actions using coding systems (non-intrusive systems that require the presence of an observer who encodes and categorizes behaviors) and the measurement of electrical "discharges" of contracting muscles (facial electromyography; EMG). However, the measuring system invented by Ekman and Friesen (2002) - "Facial Action Coding System - FACS" is the most comprehensive, complete, and versatile. Our study, carried out on about 1,500 subjects over three years of work, allowed us to highlight how the movements of the hands and upper part of the face change depending on whether the subject wears a mask or not. We have been able to identify specific alterations to the subjects’ hand movement patterns and their upper face expressions while wearing masks compared to when not wearing them. We believe that finding correlations between how body language changes when our facial expressions are impaired can provide a better understanding of the link between the face and body non-verbal language.

Keywords: facial action coding system, COVID-19, masks, facial analysis

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2071 Interactive Lecture Demonstration and Inquiry-Based Instruction in Addressing Students' Misconceptions in Electric Circuits

Authors: Mark Anthony Casimiro, Ivan Culaba, Cornelia Soto

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Misconceptions are the wrong concepts understood by the students which may come up based on what they experience and observe around their environment. This seemed to hinder students’ learning. In this study, six different misconceptions were determined by the researcher from the previous researches. Teachers play a vital role in the classroom. The use of appropriate strategies can contribute a lot in the success of teaching and learning Physics. The current study aimed to compare two strategies- Interactive Lecture Demonstration (ILD) and Inquiry-Based Instruction (IBI) in addressing students’ misconceptions in electric circuits. These two strategies are both interactive learning activities and student-centered. In ILD, the teacher demonstrates the activity and the students have their predictions while in IBI, students perform the experiments. The study used the mixed method in which quantitative and qualitative researches were combined. The main data of this study were the test scores of the students from the pretest and posttest. Likewise, an interview with the teacher, observer and students was done before, during and after the execution of the activities. Determining and Interpreting Resistive Electric Circuits Test version 2 (DIRECT v.2) was the instrument used in the study. Two sections of Grade 9 students from Kalumpang National High School were the respondents of the study. The two strategies were executed to each section; one class was assigned as the ILD group and the other class was the IBI group. The Physics teacher of the said school was the one who taught and executed the activities. The researcher taught the teacher the steps in doing the two strategies. The Department of Education level of proficiency in the Philippines was adopted in scoring and interpretation. The students’ level of proficiency was used in assessing students’ knowledge on electric circuits. The pretest result of the two groups had a p-value of 0.493 which was greater than the level of significance 0.05 (p >0.05) and it implied that the students’ level of understanding in the topic was the same before the execution of the strategies. The posttest results showed that the p-value (0.228) obtained was greater than the level of significance which is 0.05 (p> 0.05). This implied that the students from the ILD and IBI groups had the same level of understanding after the execution of the two strategies. This could be inferred that either of the two strategies- Interactive Lecture Demonstration and Inquiry-Based Instruction could be used in addressing students’ misconception in electric circuit as both had similar effect on the students’ level of understanding in the topic. The result of this study may greatly help teachers, administration, school heads think of appropriate strategies that can address misconceptions depending on the availability of their materials of their school.

Keywords: inquiry- based instruction, interactive lecture demonstration, misconceptions, mixed method

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2070 Hybrid Precoder Design Based on Iterative Hard Thresholding Algorithm for Millimeter Wave Multiple-Input-Multiple-Output Systems

Authors: Ameni Mejri, Moufida Hajjaj, Salem Hasnaoui, Ridha Bouallegue

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The technology advances have most lately made the millimeter wave (mmWave) communication possible. Due to the huge amount of spectrum that is available in MmWave frequency bands, this promising candidate is considered as a key technology for the deployment of 5G cellular networks. In order to enhance system capacity and achieve spectral efficiency, very large antenna arrays are employed at mmWave systems by exploiting array gain. However, it has been shown that conventional beamforming strategies are not suitable for mmWave hardware implementation. Therefore, new features are required for mmWave cellular applications. Unlike traditional multiple-input-multiple-output (MIMO) systems for which only digital precoders are essential to accomplish precoding, MIMO technology seems to be different at mmWave because of digital precoding limitations. Moreover, precoding implements a greater number of radio frequency (RF) chains supporting more signal mixers and analog-to-digital converters. As RF chain cost and power consumption is increasing, we need to resort to another alternative. Although the hybrid precoding architecture has been regarded as the best solution based on a combination between a baseband precoder and an RF precoder, we still do not get the optimal design of hybrid precoders. According to the mapping strategies from RF chains to the different antenna elements, there are two main categories of hybrid precoding architecture. Given as a hybrid precoding sub-array architecture, the partially-connected structure reduces hardware complexity by using a less number of phase shifters, whereas it sacrifices some beamforming gain. In this paper, we treat the hybrid precoder design in mmWave MIMO systems as a problem of matrix factorization. Thus, we adopt the alternating minimization principle in order to solve the design problem. Further, we present our proposed algorithm for the partially-connected structure, which is based on the iterative hard thresholding method. Through simulation results, we show that our hybrid precoding algorithm provides significant performance gains over existing algorithms. We also show that the proposed approach reduces significantly the computational complexity. Furthermore, valuable design insights are provided when we use the proposed algorithm to make simulation comparisons between the hybrid precoding partially-connected structure and the fully-connected structure.

Keywords: alternating minimization, hybrid precoding, iterative hard thresholding, low-complexity, millimeter wave communication, partially-connected structure

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2069 Measuring Science and Technology Innovation Capacity in Developing Countries: From a National Innovation System

Authors: Haeng A. Seo, Changseok Oh, Seung Jun Yoo

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This study attempts to examine the disparities in S&T innovation capacity from 14 developing countries to discuss how to support specific features in national innovation systems. It includes East-Asian, Middle-Asian, Central American and African countries. Here, we particularly focus on five dimensions- resources, activities, network, environment and performance- with 37 indicators. They were derived as structuring components of the relevant diagnostic model, which encompasses the whole process of S&T innovation from the input of resources to the output of economically valuable results. For many developing nations, economic industries remain weaker than actual S&T capabilities, and relevant regulatory authorities may not exist. This paper will be helpful to provide basic evidence and to set directions for better national S&T Innovation capacities and toward national competitiveness.

Keywords: developing countries, measurement, NIS, S&T innovation capacity

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2068 Mixing Time: Influence on the Compressive Strength

Authors: J. Alvarez Muñoz, Dominguez Lepe J. A.

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A suitable mixing time of the concrete, allows form a homogeneous mass, quality that leads to greater compressive strength and durability. Although there are recommendations as ASTM C94 standard these mention the time and the number of minimum and maximum speed for a ready-mix concrete of good quality, the specific behavior that would have a concrete mixed on site to variability of the mixing time is unknown. In this study was evaluated the behavior a design of mixture structural of f´c=250 kg/cm2, elaborate on site with limestone aggregate in warm sub-humid climate, subjected to different mixing times. Based on the recommendation for ready-mixed concrete ASTM C94, different times were set at 70, 90, 100, 110, 120, 140 total revolutions. A field study in which 14 works were observed where structural concrete made on site was used, allowed to set at 24 the number of revolutions to the reference mixture. For the production of concrete was used a hand feed concrete mixer with drum speed 28 RPM, the ratio w/c was 0.36 corrected, with a slump of 5-6 cm, for all mixtures. The compressive strength tests were performed at 3, 7, 14, and 28 days. The most outstanding results show increases in resistance in the mixtures of 24 to 70 revolutions between 8 and 17 percent and 70 to 90 revolutions of 3 to 8 percent. Increasing the number of revolutions at 110, 120 and 140, there was a reduction of the compressive strength of 0.5 to 8 percent. Regarding mixtures consistencies, they had a slump of 5 cm to 24, 70 and 90 rpm and less than 5 cm from 100 revolutions. Clearly, those made with more than 100 revolutions mixtures not only decrease the compressive strength but also the workability.

Keywords: compressive strength, concrete, mixing time, workability

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2067 Cause of the Disappearance of Wild Bees in Kinshasa, Democratic Republic of Congo

Authors: Sarah Ekuwo Okende, Armand Lokolo

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Gradually, the recognition of wild bees in processes affecting ecosystems and as major components of biodiversity has led to their protection as well as their areas in Kinshasa. And despite their decisive role in the well-being of men, the general public and decision-makers know nothing of the consequences of the loss of these, which are nevertheless of considerable magnitude. On this, they provide the pollination of sexual plants, and they also provide us with a number of goods that have a direct economic value, such as food, medicines, etc. And yet today, more than half of these wild bee species are threatened in Kinshasa. The causes of this phenomenon are largely unknown to the general public in the Kinshasa region. The objective of this study is to find the causes leading to the disappearance of wild bee species in Kinshasa. Also, this research contributes to current knowledge of the biodiversity of wild bees in the Kinshasa region and helps the authorities to develop a good policy for the conservation or safeguarding of this biodiversity, which plays a key role in maintaining the integrity of our ecosystems. We carried out field surveys using interview sheets in the forest areas of Kinshasa where wild bees populated them. To achieve this, an interview sheet was made, and it included questions on the causes of the disappearance of wild bees and the destruction of forest areas. The interviews were carried out with the natives of these forest areas. The results of this study show us that the destruction of habitats or natural areas and the use of pesticides are the causes of the disappearance of these wild bees.

Keywords: wild bees, pollinisation, forest, biodiversity, habitats, ecosystem, destruction, pesticide

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2066 Potentials of Underutilised Crops in the Nigerian Farming Systems for Sustainable Food Production and Economic Empowerment

Authors: Jesse Silas Mshelia, Michael Mamman Degri, Akeweta Emmanuel Samaila

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This review was conducted in the North-Eastern part of Nigeria where there are a lot of challenges of poverty and low level of productivity of farmlands as a result of dwindling soil fertility and dependence on crops that are not so much adopted to the soil and climatic condition and the prevailing farming systems of the area which is predominantly mixed cropping. The crops that are neglected are well fitted into this system of production and yield better with the low level of input and management and give a higher profit margin. These crops, the farmers have mastered the production techniques, but do not have the scientific knowledge to improve the quality of the seed and the products hence need the intervention of modern technologies to benefit maximally from the full potentials of these crops.

Keywords: farming systems, neglected crops, potentials, underutilised

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2065 Theoretical Evaluation of the Effect of Solvent on the Feasibility of the Reaction of 2-Chlorobenzimidazole With Four N,N′-Cyclic Azomethine Imines to Construct Polycyclic Benzimidazoles

Authors: Mohamed Abdoul-Hakim, A. Zeroual, H. Garmes

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In this work, we theoretically evaluated the reactivity of four 4-methyl-3-oxo-1,2-pyrazolidinium ylides with 2-Chlorobenzimidazole in MeOH in basic medium using DFT at the B3LYP/6-311+G(d,p) level. The analysis of the results shows that apart from its ability to retain its electrons, the deprotonated 2-Chlorobenzimidazole has a higher nucleophilic character. The reaction requires energy input to initiate the nucleophilic attack of the 2-Chlorobenzimidazole anion, and the inclusion of the solvent effect facilitates the formation of two regioisomers via an intramolecular vinyl nucleophilic substitution (SNVi). The transition states of this latter step are stabilized by charge transfer interactions σ(N-C) →σ*(C-Cl) for the more favorable regioisomer and n(N)→σ*(C-Cl) for the other regioisomer.

Keywords: benzonitrile N-oxide, DFT, intramolecular vinyl nucleophilic substitution (SNVi), 4-methyl-3-OXO-1, 2-pyrazolidinium ylides

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2064 Optimization of MAG Welding Process Parameters Using Taguchi Design Method on Dead Mild Steel

Authors: Tadele Tesfaw, Ajit Pal Singh, Abebaw Mekonnen Gezahegn

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Welding is a basic manufacturing process for making components or assemblies. Recent welding economics research has focused on developing the reliable machinery database to ensure optimum production. Research on welding of materials like steel is still critical and ongoing. Welding input parameters play a very significant role in determining the quality of a weld joint. The metal active gas (MAG) welding parameters are the most important factors affecting the quality, productivity and cost of welding in many industrial operations. The aim of this study is to investigate the optimization process parameters for metal active gas welding for 60x60x5mm dead mild steel plate work-piece using Taguchi method to formulate the statistical experimental design using semi-automatic welding machine. An experimental study was conducted at Bishoftu Automotive Industry, Bishoftu, Ethiopia. This study presents the influence of four welding parameters (control factors) like welding voltage (volt), welding current (ampere), wire speed (m/min.), and gas (CO2) flow rate (lit./min.) with three different levels for variability in the welding hardness. The objective functions have been chosen in relation to parameters of MAG welding i.e., welding hardness in final products. Nine experimental runs based on an L9 orthogonal array Taguchi method were performed. An orthogonal array, signal-to-noise (S/N) ratio and analysis of variance (ANOVA) are employed to investigate the welding characteristics of dead mild steel plate and used in order to obtain optimum levels for every input parameter at 95% confidence level. The optimal parameters setting was found is welding voltage at 22 volts, welding current at 125 ampere, wire speed at 2.15 m/min and gas flow rate at 19 l/min by using the Taguchi experimental design method within the constraints of the production process. Finally, six conformations welding have been carried out to compare the existing values; the predicated values with the experimental values confirm its effectiveness in the analysis of welding hardness (quality) in final products. It is found that welding current has a major influence on the quality of welded joints. Experimental result for optimum setting gave a better hardness of welding condition than initial setting. This study is valuable for different material and thickness variation of welding plate for Ethiopian industries.

Keywords: Weld quality, metal active gas welding, dead mild steel plate, orthogonal array, analysis of variance, Taguchi method

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2063 Modeling of Hydrogen Production by Inductively Coupled Methane Plasma for Input Power Pin=700W

Authors: Abdelatif Gadoum, Djilali Benyoucef, Mouloudj Hadj, Alla Eddine Toubal Maamar, Mohamed Habib Allah Lahoual

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Hydrogen occurs naturally in the form of chemical compounds, most often in water and hydrocarbons. The main objective of this study is 2D modeling of hydrogen production in inductively coupled plasma in methane at low pressure. In the present model, we include the motions and the collisions of both neutral and charged particles by considering 19 species (i.e in total ; neutrals, radicals, ions, and electrons), and more than 120 reactions (electron impact with methane, neutral-neutral, neutral-ions and surface reactions). The results show that the rate conversion of methane reach 90% and the hydrogen production is about 30%.

Keywords: hydrogen production, inductively coupled plasma, fluid model, methane plasma

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2062 Performance Evaluation of Distributed and Co-Located MIMO LTE Physical Layer Using Wireless Open-Access Research Platform

Authors: Ishak Suleiman, Ahmad Kamsani Samingan, Yeoh Chun Yeow, Abdul Aziz Bin Abdul Rahman

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In this paper, we evaluate the benefits of distributed 4x4 MIMO LTE downlink systems compared to that of the co-located 4x4 MIMO LTE downlink system. The performance evaluation was carried out experimentally by using Wireless Open-Access Research Platform (WARP), where the comparison between the 4x4 MIMO LTE transmission downlink system in distributed and co-located techniques was examined. The measured Error Vector Magnitude (EVM) results showed that the distributed technique achieved better system performance compared to the co-located arrangement.

Keywords: multiple-input-multiple-output (MIMO), distributed MIMO, co-located MIMO, LTE

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2061 Probing Language Models for Multiple Linguistic Information

Authors: Bowen Ding, Yihao Kuang

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In recent years, large-scale pre-trained language models have achieved state-of-the-art performance on a variety of natural language processing tasks. The word vectors produced by these language models can be viewed as dense encoded presentations of natural language that in text form. However, it is unknown how much linguistic information is encoded and how. In this paper, we construct several corresponding probing tasks for multiple linguistic information to clarify the encoding capabilities of different language models and performed a visual display. We firstly obtain word presentations in vector form from different language models, including BERT, ELMo, RoBERTa and GPT. Classifiers with a small scale of parameters and unsupervised tasks are then applied on these word vectors to discriminate their capability to encode corresponding linguistic information. The constructed probe tasks contain both semantic and syntactic aspects. The semantic aspect includes the ability of the model to understand semantic entities such as numbers, time, and characters, and the grammatical aspect includes the ability of the language model to understand grammatical structures such as dependency relationships and reference relationships. We also compare encoding capabilities of different layers in the same language model to infer how linguistic information is encoded in the model.

Keywords: language models, probing task, text presentation, linguistic information

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2060 Hepatoprotective Effect of Oleuropein against Cisplatin-Induced Liver Damage in Rat

Authors: Salim Cerig, Fatime Geyikoglu, Murat Bakir, Suat Colak, Merve Sonmez, Kubra Koc

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Cisplatin (CIS) is one of the most effective an anticancer drug and also toxic to cells by activating oxidative stress. Oleuropein (OLE) has key role against oxidative stress in mammalian cells, but the role of this antioxidant in the toxicity of CIS remains unknown. The aim of the present study was to investigate the efficacy of OLE on CIS-induced liver damages in male rats. With this aim, male Sprague Dawley rats were randomly assigned to one of eight groups: Control group; the group treated with 7 mg/kg/day CIS; the groups treated with 50, 100 and 200 mg/kg/day OLE (i.p.); and the groups treated with OLE for three days starting at 24 h following CIS injection. After 4 days of injections, serum was provided to assess the blood AST, ALT and LDH values. The liver tissues were removed for histological, biochemical (TAC, TOS and MDA) and genotoxic evaluations. In the CIS treated group, the whole liver tissue showed significant histological changes. Also, CIS significantly increased both the incidence of oxidative stress and the induction of 8-hydroxy-deoxyguanosine (8-OH-dG). Moreover, the rats taking CIS have abnormal results on liver function tests. However, these parameters reached to the normal range after administration of OLE for 3 days. Finally, OLE demonstrated an acceptable high potential and was effective in attenuating CIS-induced liver injury. In this trial, the 200 mg/kg dose of OLE firstly appeared to induce the most optimal protective response.

Keywords: antioxidant response, cisplatin, histology, liver, oleuropein, 8-OhdG

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2059 Two Day Ahead Short Term Load Forecasting Neural Network Based

Authors: Firas M. Tuaimah

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This paper presents an Artificial Neural Network based approach for short-term load forecasting and exactly for two days ahead. Two seasons have been discussed for Iraqi power system, namely summer and winter; the hourly load demand is the most important input variables for ANN based load forecasting. The recorded daily load profile with a lead time of 1-48 hours for July and December of the year 2012 was obtained from the operation and control center that belongs to the Ministry of Iraqi electricity. The results of the comparison show that the neural network gives a good prediction for the load forecasting and for two days ahead.

Keywords: short-term load forecasting, artificial neural networks, back propagation learning, hourly load demand

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2058 Efficient Principal Components Estimation of Large Factor Models

Authors: Rachida Ouysse

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This paper proposes a constrained principal components (CnPC) estimator for efficient estimation of large-dimensional factor models when errors are cross sectionally correlated and the number of cross-sections (N) may be larger than the number of observations (T). Although principal components (PC) method is consistent for any path of the panel dimensions, it is inefficient as the errors are treated to be homoskedastic and uncorrelated. The new CnPC exploits the assumption of bounded cross-sectional dependence, which defines Chamberlain and Rothschild’s (1983) approximate factor structure, as an explicit constraint and solves a constrained PC problem. The CnPC method is computationally equivalent to the PC method applied to a regularized form of the data covariance matrix. Unlike maximum likelihood type methods, the CnPC method does not require inverting a large covariance matrix and thus is valid for panels with N ≥ T. The paper derives a convergence rate and an asymptotic normality result for the CnPC estimators of the common factors. We provide feasible estimators and show in a simulation study that they are more accurate than the PC estimator, especially for panels with N larger than T, and the generalized PC type estimators, especially for panels with N almost as large as T.

Keywords: high dimensionality, unknown factors, principal components, cross-sectional correlation, shrinkage regression, regularization, pseudo-out-of-sample forecasting

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2057 ZVZCT PWM Boost DC-DC Converter

Authors: Ismail Aksoy, Haci Bodur, Nihan Altintaş

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This paper introduces a boost converter with a new active snubber cell. In this circuit, all of the semiconductor components in the converter softly turns on and turns off with the help of the active snubber cell. Compared to the other converters, the proposed converter has advantages of size, number of components and cost. The main feature of proposed converter is that the extra voltage stresses do not occur on the main switches and main diodes. Also, the current stress on the main switch is acceptable level. Moreover, the proposed converter can operates under light load conditions and wide input line voltage. In this study, the operating principle of the proposed converter is presented and its operation is verified with the Proteus simulation software for a 1 kW and 100 kHz model.

Keywords: active snubber cell, boost converter, zero current switching, zero voltage switching

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2056 The Analysis of Different Classes of Weighted Fuzzy Petri Nets and Their Features

Authors: Yurii Bloshko, Oksana Olar

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This paper presents the analysis of 6 different classes of Petri nets: fuzzy Petri nets (FPN), generalized fuzzy Petri nets (GFPN), parameterized fuzzy Petri nets (PFPN), T2GFPN, flexible generalized fuzzy Petri nets (FGFPN), binary Petri nets (BPN). These classes were simulated in the special software PNeS® for the analysis of its pros and cons on the example of models which are dedicated to the decision-making process of passenger transport logistics. The paper includes the analysis of two approaches: when input values are filled with the experts’ knowledge; when fuzzy expectations represented by output values are added to the point. These approaches fulfill the possibilities of triples of functions which are replaced with different combinations of t-/s-norms.

Keywords: fuzzy petri net, intelligent computational techniques, knowledge representation, triangular norms

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2055 Optimal Design of Step-Stress Partially Life Test Using Multiply Censored Exponential Data with Random Removals

Authors: Showkat Ahmad Lone, Ahmadur Rahman, Ariful Islam

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The major assumption in accelerated life tests (ALT) is that the mathematical model relating the lifetime of a test unit and the stress are known or can be assumed. In some cases, such life–stress relationships are not known and cannot be assumed, i.e. ALT data cannot be extrapolated to use condition. So, in such cases, partially accelerated life test (PALT) is a more suitable test to be performed for which tested units are subjected to both normal and accelerated conditions. This study deals with estimating information about failure times of items under step-stress partially accelerated life tests using progressive failure-censored hybrid data with random removals. The life data of the units under test is considered to follow exponential life distribution. The removals from the test are assumed to have binomial distributions. The point and interval maximum likelihood estimations are obtained for unknown distribution parameters and tampering coefficient. An optimum test plan is developed using the D-optimality criterion. The performances of the resulting estimators of the developed model parameters are evaluated and investigated by using a simulation algorithm.

Keywords: binomial distribution, d-optimality, multiple censoring, optimal design, partially accelerated life testing, simulation study

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2054 Erosion Modeling of Surface Water Systems for Long Term Simulations

Authors: Devika Nair, Sean Bellairs, Ken Evans

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Flow and erosion modeling provides an avenue for simulating the fine suspended sediment in surface water systems like streams and creeks. Fine suspended sediment is highly mobile, and many contaminants that may have been released by any sort of catchment disturbance attach themselves to these sediments. Therefore, a knowledge of fine suspended sediment transport is important in assessing contaminant transport. The CAESAR-Lisflood Landform Evolution Model, which includes a hydrologic model (TOPMODEL) and a hydraulic model (Lisflood), is being used to assess the sediment movement in tropical streams on account of a disturbance in the catchment of the creek and to determine the dynamics of sediment quantity in the creek through the years by simulating the model for future years. The accuracy of future simulations depends on the calibration and validation of the model to the past and present events. Calibration and validation of the model involve finding a combination of parameters of the model, which, when applied and simulated, gives model outputs similar to those observed for the real site scenario for corresponding input data. Calibrating the sediment output of the CAESAR-Lisflood model at the catchment level and using it for studying the equilibrium conditions of the landform is an area yet to be explored. Therefore, the aim of the study was to calibrate the CAESAR-Lisflood model and then validate it so that it could be run for future simulations to study how the landform evolves over time. To achieve this, the model was run for a rainfall event with a set of parameters, plus discharge and sediment data for the input point of the catchment, to analyze how similar the model output would behave when compared with the discharge and sediment data for the output point of the catchment. The model parameters were then adjusted until the model closely approximated the real site values of the catchment. It was then validated by running the model for a different set of events and checking that the model gave similar results to the real site values. The outcomes demonstrated that while the model can be calibrated to a greater extent for hydrology (discharge output) throughout the year, the sediment output calibration may be slightly improved by having the ability to change parameters to take into account the seasonal vegetation growth during the start and end of the wet season. This study is important to assess hydrology and sediment movement in seasonal biomes. The understanding of sediment-associated metal dispersion processes in rivers can be used in a practical way to help river basin managers more effectively control and remediate catchments affected by present and historical metal mining.

Keywords: erosion modelling, fine suspended sediments, hydrology, surface water systems

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2053 On ‘Freaks’ and the Feminine in Margaret Atwood’s ‘Lusus Naturae’

Authors: Shahd Alshammari

Abstract:

This paper considers one of Margaret Atwood’s short stories ‘Lusus Naturae'. Through a critical lens that makes use of Julia Kristeva’s work on Powers of Horror and abjection, this paper suggests that the monstrous girl is the disabled woman, the abject in society. The monster is used as a metaphor for the unknown, the misunderstood, and the ‘different’ woman. Culturally Relevant Teaching (CRT) is a pedagogy that calls for making course material accessible and relevant to students. Through the study of literary texts, we are able to help create agency inside and outside the classroom. Stories are a necessary part of establishing connections across borders and boundaries. Stories are meant to raise awareness both inside and outside the classroom. The discussion is equally important, and the text is meant to facilitate relevant questions that the students need to consider when it comes to identity. Questions to consider are: what does it mean to be a ‘girl’ today, and what implications and consequences are at hand when you fail to perform this gendered identity? Gender is sometimes a fatal bond in the Middle East, and even more so, is the disability. In the case of our unnamed protagonist, she undergoes a process of un-becoming, a non-linear process of growing up. In a sense, it is a counter-Bildungsroman. The reading of this text emphasizes that a non-linear narrative is sometimes necessary for the female protagonist’s self-awareness and development. Discussion in class facilitates this sense of agency and questioning of gender and disability.

Keywords: disability, gender, literature, pedagogy

Procedia PDF Downloads 642
2052 Financial Inclusion as Twig of Internally Generated Revenue From Entrepreneurial Venture: A University Funding Alternate

Authors: Anifowose Oluwafemi Dele, Ngah Rohana, Hasni Abdulahi

Abstract:

The economic crisis, which resulted in university funding cuts with an astronomically devastating impact on teaching and research around the world. Sequel to this, Nigerian universities are in disarray due to insufficient government funding and are under pressure to discover new financial streams of Internally Generated Revenue (IGR) to disentangle finance-related teething problems and most tangible means of outsourcing finance inclusively for the creation of more entrepreneurial ventures through the possibilities of prudent IGR management. To the best of our knowledge, one way to address this still-unknown or underappreciated cog is through the strategic use of IGR and the outsourcing of financing for the launch of entrepreneurial ventures. As a result, it is critical to investigate and evaluate financial inclusion through prudently managed IGR to achieve greater financial inclusion for more long-term entrepreneurial ventures. Justifying the need to look inward and devise mechanisms for strong instruments internal fund raising and managing cash inflows to benefit university entrepreneurial ventures to increase the University's IGR for the benefit of the university and its stakeholders. The paper concludes that University Managers must fully accept the use of genuine means of boosting IGR through financial inclusion of in-house funds to aggressively established IGR boosting and the creation of entrepreneurial ventures that could serve as an alternative to inadequate government funding.

Keywords: government funding, university managers, financial inclusion, entrepreneurial venture

Procedia PDF Downloads 64
2051 Early Initiation of Breastfeeding among Postpartum Mothers at Two Rwandan Hospitals

Authors: Joella Mukashyaka, Rose Mukarubayiza, Emmanuel Habumugisha, Francois-Xavier Sunday, Kellen Muganwa, Valens Mbarushimana, Pamela Meharry

Abstract:

Background: Breastfeeding in the first hour post-birth can decrease neonatal morbidity and mortality. Disease prevention and health outcomes differ immensely between newborns who receive human milk and those who do not. Rwanda has high breastfeeding rates, though factors associated with early initiation of breastfeeding (EIBF) are unknown. Objective: To assess factors associated with EIBF among mothers in immediate postpartum units at two hospitals. Methods: A cross-sectional study design and a convenience sample of 187 mothers were used. An interviewer-administered questionnaire was used for data collection. A Chi-square test showed the relationship between EIBF and sociodemographic factors. Results: The findings showed less than one quarter (20.5%) breastfed within the first hour after birth. The majority was < 25 years (52.4%), had some primary education (27.7%) employed (66.7%), urban dweller (58.1%), attendance of one ANC visit or more (81.3%), vaginal birth (58.8%), and did not receive EIBF health education (92.0%). The majority (78.5%) was too tired to initiate breastfeeding, and many supplemented (41.9%) due to perceived insufficient breastmilk. Conclusion: Most mothers did not initiate breastfeeding within the first hour after birth. Sociodemographic factors were associated with EIBF. A program to promote, protect, and support EIBF is urgently needed the community.

Keywords: breastfeeding, early initiation, neonates, morbidity, mortality, sub-Saharan Africa

Procedia PDF Downloads 68
2050 The Relationship between Energy Consumption and Economic Growth in Turkey: A Time Series Analysis

Authors: Burcu Guvenek, Volkan Alptekin

Abstract:

Turkey is a country in the process of development and its economy has undergone structural reforms in order to realize a sustainable development and energy has vital role as a basic input for this aim. Turkey has been in the process of economic growth and development and, because of this, has an increasing energy need. This paper investigates relationship between economic growth and electricity consumption using annual data for Turkey between 1970-2008 by using bounds test. As economic growth and energy consumption variables used in empirical analysis was different order of integration I(0) and I(1), we employed bounds test approach. We have not found co-integration relationship between the variables.

Keywords: bounds test, economic growth, energy consumption, Turkey

Procedia PDF Downloads 348
2049 Self-Calibration of Fish-Eye Camera for Advanced Driver Assistance Systems

Authors: Atef Alaaeddine Sarraj, Brendan Jackman, Frank Walsh

Abstract:

Tomorrow’s car will be more automated and increasingly connected. Innovative and intuitive interfaces are essential to accompany this functional enrichment. For that, today the automotive companies are competing to offer an advanced driver assistance system (ADAS) which will be able to provide enhanced navigation, collision avoidance, intersection support and lane keeping. These vision-based functions require an accurately calibrated camera. To achieve such differentiation in ADAS requires sophisticated sensors and efficient algorithms. This paper explores the different calibration methods applicable to vehicle-mounted fish-eye cameras with arbitrary fields of view and defines the first steps towards a self-calibration method that adequately addresses ADAS requirements. In particular, we present a self-calibration method after comparing different camera calibration algorithms in the context of ADAS requirements. Our method gathers data from unknown scenes while the car is moving, estimates the camera intrinsic and extrinsic parameters and corrects the wide-angle distortion. Our solution enables continuous and real-time detection of objects, pedestrians, road markings and other cars. In contrast, other camera calibration algorithms for ADAS need pre-calibration, while the presented method calibrates the camera without prior knowledge of the scene and in real-time.

Keywords: advanced driver assistance system (ADAS), fish-eye, real-time, self-calibration

Procedia PDF Downloads 236
2048 Predicting the Uniaxial Strength Distribution of Brittle Materials Based on a Uniaxial Test

Authors: Benjamin Sonnenreich

Abstract:

Brittle fracture failure probability is best described using a stochastic approach which is based on the 'weakest link concept' and the connection between a microstructure and macroscopic fracture scale. A general theoretical and experimental framework is presented to predict the uniaxial strength distribution according to independent uniaxial test data. The framework takes as input the applied stresses, the geometry, the materials, the defect distributions and the relevant random variables from uniaxial test results and gives as output an overall failure probability that can be used to improve the reliability of practical designs. Additionally, the method facilitates comparisons of strength data from several sources, uniaxial tests, and sample geometries.

Keywords: brittle fracture, strength distribution, uniaxial, weakest link concept

Procedia PDF Downloads 312
2047 Identifying Protein-Coding and Non-Coding Regions in Transcriptomes

Authors: Angela U. Makolo

Abstract:

Protein-coding and Non-coding regions determine the biology of a sequenced transcriptome. Research advances have shown that Non-coding regions are important in disease progression and clinical diagnosis. Existing bioinformatics tools have been targeted towards Protein-coding regions alone. Therefore, there are challenges associated with gaining biological insights from transcriptome sequence data. These tools are also limited to computationally intensive sequence alignment, which is inadequate and less accurate to identify both Protein-coding and Non-coding regions. Alignment-free techniques can overcome the limitation of identifying both regions. Therefore, this study was designed to develop an efficient sequence alignment-free model for identifying both Protein-coding and Non-coding regions in sequenced transcriptomes. Feature grouping and randomization procedures were applied to the input transcriptomes (37,503 data points). Successive iterations were carried out to compute the gradient vector that converged the developed Protein-coding and Non-coding Region Identifier (PNRI) model to the approximate coefficient vector. The logistic regression algorithm was used with a sigmoid activation function. A parameter vector was estimated for every sample in 37,503 data points in a bid to reduce the generalization error and cost. Maximum Likelihood Estimation (MLE) was used for parameter estimation by taking the log-likelihood of six features and combining them into a summation function. Dynamic thresholding was used to classify the Protein-coding and Non-coding regions, and the Receiver Operating Characteristic (ROC) curve was determined. The generalization performance of PNRI was determined in terms of F1 score, accuracy, sensitivity, and specificity. The average generalization performance of PNRI was determined using a benchmark of multi-species organisms. The generalization error for identifying Protein-coding and Non-coding regions decreased from 0.514 to 0.508 and to 0.378, respectively, after three iterations. The cost (difference between the predicted and the actual outcome) also decreased from 1.446 to 0.842 and to 0.718, respectively, for the first, second and third iterations. The iterations terminated at the 390th epoch, having an error of 0.036 and a cost of 0.316. The computed elements of the parameter vector that maximized the objective function were 0.043, 0.519, 0.715, 0.878, 1.157, and 2.575. The PNRI gave an ROC of 0.97, indicating an improved predictive ability. The PNRI identified both Protein-coding and Non-coding regions with an F1 score of 0.970, accuracy (0.969), sensitivity (0.966), and specificity of 0.973. Using 13 non-human multi-species model organisms, the average generalization performance of the traditional method was 74.4%, while that of the developed model was 85.2%, thereby making the developed model better in the identification of Protein-coding and Non-coding regions in transcriptomes. The developed Protein-coding and Non-coding region identifier model efficiently identified the Protein-coding and Non-coding transcriptomic regions. It could be used in genome annotation and in the analysis of transcriptomes.

Keywords: sequence alignment-free model, dynamic thresholding classification, input randomization, genome annotation

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2046 An Improved Cooperative Communication Scheme for IoT System

Authors: Eui-Hak Lee, Jae-Hyun Ro, Hyoung-Kyu Song

Abstract:

In internet of things (IoT) system, the communication scheme with reliability and low power is required to connect a terminal. Cooperative communication can achieve reliability and lower power than multiple-input multiple-output (MIMO) system. Cooperative communication increases the reliability with low power, but decreases a throughput. It has a weak point that the communication throughput is decreased. In this paper, a novel scheme is proposed to increase the communication throughput. The novel scheme is a transmission structure that increases transmission rate. And a decoding scheme according to the novel transmission structure is proposed. Simulation results show that the proposed scheme increases the throughput without bit error rate (BER) performance degradation.

Keywords: cooperative communication, IoT, STBC, transmission rate

Procedia PDF Downloads 385
2045 Biological Activities of Flaxseed Peptides (Linusorbs)

Authors: Youn Young Shim, Ji Hye Kim, Jae Youl Cho, Martin J. T. Reaney

Abstract:

Flaxseed (Linum usitatissimum L.) is gaining popularity in the food industry as a superfood due to its health-promoting properties. The flax plant synthesizes an array of biologically active cyclic peptides or linusorbs (LOs, a.k.a. cyclolinopeptides) from three or more ribosome-derived precursors. [1–9-NαC]-linusorb B3 and [1–9-NαC]-linusorb B2, suppress immunity, induce apoptosis in human epithelial cancer cell line (Calu-3) cells, and inhibit T-cell proliferation, but the mechanism of LOs action is unknown. Using gene expression analysis in nematode cultures and human cancer cell lines, we have observed that LOs exert their activity, in part, through induction of apoptosis. Specific LOs’ properties include: 1) distribution throughout the body after flaxseed consumption; 2) induce heat shock protein (HSP) 70A production as an indicator of stress and address the issue in Caenorhabditis elegans (exposure of nematode cultures to [1–9-NαC]-linusorb B3 induced a 30% increase in production of the HSP 70A protein); 3) induce apoptosis in Calu-3 cells; and 4) modulate regulatory genes in microarray analysis. These diverse activities indicate that LOs might induce apoptosis in cancer cells or act as versatile platforms to deliver a variety of biologically active molecules for cancer therapy.

Keywords: flaxseed, linusorb, cyclic peptide, orbitides, heat shock protein, apoptosis, anti-cancer

Procedia PDF Downloads 123