Search results for: channel length modulation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4270

Search results for: channel length modulation

3790 Radial Variation of Anatomical Characteristics in Three Native Fast-Growing Species Growing in South Kalimantan, Indonesia

Authors: Wiwin Tyas Istikowati, Futoshi Ishiguri, Haruna Aisho, Budi Sutiya, Imam Wahyudi, Kazuya Iizuka, Shinso Yokota

Abstract:

The objective of this study was to investigate the anatomical characteristics of three native fast-growing species, terap (Artocarpus elasticus Reinw. ex Blume), medang (Neolitsea latifolia (Blume) S. Moore), and balik angin (Alphitonia excelsa (Fenzel) Reissek ex Benth) growing in the secondary forest in South Kalimantan, Indonesia for evaluating the possibility of tree breeding for wood quality. Cell lengths were investigated for 5 trees in each species at several different height positions (1.0, 3.0, 5.0, 7.0, 9.0, and 11.0 m above the ground). The mean values of fiber and vessel element lengths in terap, medang, and balik angin were 1.52 and 0.44, 1.16 and 0.53, and 1.02 and 0.49 mm, respectively. Fiber length in terap and balik angin gradually increased from pith to bark, whereas it increased up to 2 cm and then became nearly constant to the bark in medang. Vessel element length was almost constant from pith to bark in terap and balik angin, while slightly increased from pith to bark in medang. Fiber length in terap has a fluctuation pattern from ground level to top of the tree. It decreased up to 3 m above the ground, increased up to 5 m, and then decreased to the top of the tree. On the other hand, vessel element length slightly increased up to 5 m above the ground, and then decreased to the top of the tree. Both fiber and vessel element lengths in medang were almost constant from ground level to top of the tree, whereas decreased from ground level to top of the tree in balik angin. Significant difference at 1% level among trees was found in both fiber and vessel element length in both radial and longitudinal directions for terap and medang. Based on obtained results, it is concluded that the wood quality in fiber and vessel element lengths of terap and medang can be improved by tree breeding programs.

Keywords: anatomical properties, fiber length, vessel elements length, fast-growing species

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3789 Analysis of Gait Characteristics Using Dynamic Foot Scanner in Type 2 Diabetes Mellitus

Authors: C. G. Shashi Kumar, G. Arun Maiya, H. Manjunath Hande, K. V. Rajagopal

Abstract:

Background: Diabetes mellitus (DM) is a metabolic disorder with involvement of neurovascular and muscular system. Studies have documented that the gait parameter is altered in type 2 diabetes mellitus with peripheral neuropathy. However, there is a dearth of literature regarding the gait characteristics in type 2 diabetes mellitus (T2DM) without peripheral neuropathy. Therefore, the present study is focused on identifying gait changes in early type 2 diabetes mellitus without peripheral neuropathy. Objective: To analyze the gait characteristics in Type 2 diabetes mellitus without peripheral neuropathy. Methods: After obtaining ethical clearance from Institutional Ethical Committee (IEC), 36 T2DM without peripheral neuropathy and 32 matched healthy subjects were recruited. Gait characteristics (step duration, gait cycle length, gait cycle duration, stride duration, step length, double stance duration) of all the subjects were analyzed using Windtrack dynamic foot scanner. Data were analyzed using Independent‘t’ test to find the difference between the groups (step duration, gait cycle length, gait cycle duration) and Mann-Whitney test was used to analyze the step length and double stance duration to find difference between the groups. Level of significance was kept at P<0.05. Results: Result analysis showed significant decrease in step duration, gait cycle length, gait cycle duration, step length, double stance duration in T2DM subjects as compared to healthy subjects. We also observed a mean increase in stride duration in T2DM subjects compared to healthy subjects.

Keywords: type 2 diabetes mellitus, dynamic foot scan, gait characteristics, medical and health sciences

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3788 Using Personalized Spiking Neural Networks, Distinct Techniques for Self-Governing

Authors: Brwa Abdulrahman Abubaker

Abstract:

Recently, there has been a lot of interest in the difficult task of applying reinforcement learning to autonomous mobile robots. Conventional reinforcement learning (TRL) techniques have many drawbacks, such as lengthy computation times, intricate control frameworks, a great deal of trial and error searching, and sluggish convergence. In this paper, a modified Spiking Neural Network (SNN) is used to offer a distinct method for autonomous mobile robot learning and control in unexpected surroundings. As a learning algorithm, the suggested model combines dopamine modulation with spike-timing-dependent plasticity (STDP). In order to create more computationally efficient, biologically inspired control systems that are adaptable to changing settings, this work uses the effective and physiologically credible Izhikevich neuron model. This study is primarily focused on creating an algorithm for target tracking in the presence of obstacles. Results show that the SNN trained with three obstacles yielded an impressive 96% success rate for our proposal, with collisions happening in about 4% of the 214 simulated seconds.

Keywords: spiking neural network, spike-timing-dependent plasticity, dopamine modulation, reinforcement learning

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3787 A Portable Cognitive Tool for Engagement Level and Activity Identification

Authors: Terry Teo, Sun Woh Lye, Yufei Li, Zainuddin Zakaria

Abstract:

Wearable devices such as Electroencephalography (EEG) hold immense potential in the monitoring and assessment of a person’s task engagement. This is especially so in remote or online sites. Research into its use in measuring an individual's cognitive state while performing task activities is therefore expected to increase. Despite the growing number of EEG research into brain functioning activities of a person, key challenges remain in adopting EEG for real-time operations. These include limited portability, long preparation time, high number of channel dimensionality, intrusiveness, as well as level of accuracy in acquiring neurological data. This paper proposes an approach using a 4-6 EEG channels to determine the cognitive states of a subject when undertaking a set of passive and active monitoring tasks of a subject. Air traffic controller (ATC) dynamic-tasks are used as a proxy. The work found that when using the channel reduction and identifier algorithm, good trend adherence of 89.1% can be obtained between a commercially available BCI 14 channel Emotiv EPOC+ EEG headset and that of a carefully selected set of reduced 4-6 channels. The approach can also identify different levels of engagement activities ranging from general monitoring ad hoc and repeated active monitoring activities involving information search, extraction, and memory activities.

Keywords: assessment, neurophysiology, monitoring, EEG

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3786 Allelopathic Effects of Eucalyptus camaldulensis and E. gomphocephala on Seed Germination and Seedling Growth of Barley

Authors: Sallah S. El-Ammari, Mona. S. Hasan

Abstract:

This research is aimed to study allelopathic effects of two wind breakers Eucalyptus camaldulensis and E.gomphocephala on germination and growth of barley using aqueous extracts of leaves at 0.5, 1, 5, and 10% concentrations for treatment of barley caryopsis in petri dishes incubated in growth chamber. Distilled water was used in the experiment as a control. Seed germination was recorded on daily basis for five days. After ten days measurements of root length, shoot length, fresh and dry weight of root and shoot were taken. With the exception of 0.5% E. gomphocephala extract effect on length and dry weight of barley root, all the tested extract concentrations for both eucalyptus species significantly decreased the percent and speed of germination, root and shoot length, fresh and dry weight of root and shoot of barley compared to the control. For both species the allelopathic effect was significantly increasing with the increase of the extract concentration. Although, higher allelopathic effect was shown by E. camaldulensis, the results indicating that both eucalyptus species should not be recommended as wind breakers for barley fields.

Keywords: allelopathy, eucalyptus, barley, Libya

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3785 A Dissipative Particle Dynamics Study of a Capsule in Microfluidic Intracellular Delivery System

Authors: Nishanthi N. S., Srikanth Vedantam

Abstract:

Intracellular delivery of materials has always proved to be a challenge in research and therapeutic applications. Usually, vector-based methods, such as liposomes and polymeric materials, and physical methods, such as electroporation and sonoporation have been used for introducing nucleic acids or proteins. Reliance on exogenous materials, toxicity, off-target effects was the short-comings of these methods. Microinjection was an alternative process which addressed the above drawbacks. However, its low throughput had hindered its adoption widely. Mechanical deformation of cells by squeezing them through constriction channel can cause the temporary development of pores that would facilitate non-targeted diffusion of materials. Advantages of this method include high efficiency in intracellular delivery, a wide choice of materials, improved viability and high throughput. This cell squeezing process can be studied deeper by employing simple models and efficient computational procedures. In our current work, we present a finite sized dissipative particle dynamics (FDPD) model to simulate the dynamics of the cell flowing through a constricted channel. The cell is modeled as a capsule with FDPD particles connected through a spring network to represent the membrane. The total energy of the capsule is associated with linear and radial springs in addition to constraint of the fixed area. By performing detailed simulations, we studied the strain on the membrane of the capsule for channels with varying constriction heights. The strain on the capsule membrane was found to be similar though the constriction heights vary. When strain on the membrane was correlated to the development of pores, we found higher porosity in capsule flowing in wider channel. This is due to localization of strain to a smaller region in the narrow constriction channel. But the residence time of the capsule increased as the channel constriction narrowed indicating that strain for an increased time will cause less cell viability.

Keywords: capsule, cell squeezing, dissipative particle dynamics, intracellular delivery, microfluidics, numerical simulations

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3784 Correlation Mapping for Measuring Platelet Adhesion

Authors: Eunseop Yeom

Abstract:

Platelets can be activated by the surrounding blood flows where a blood vessel is narrowed as a result of atherosclerosis. Numerous studies have been conducted to identify the relation between platelets activation and thrombus formation. To measure platelet adhesion, this study proposes an image analysis technique. Blood samples are delivered in the microfluidic channel, and then platelets are activated by a stenotic micro-channel with 90% severity. By applying proposed correlation mapping, which visualizes decorrelation of the streaming blood flow, the area of adhered platelets (APlatelet) was estimated without labeling platelets. In order to evaluate the performance of correlation mapping on the detection of platelet adhesion, the effect of tile size was investigated by calculating 2D correlation coefficients with binary images obtained by manual labeling and the correlation mapping method with different sizes of the square tile ranging from 3 to 50 pixels. The maximum 2D correlation coefficient is observed with the optimum tile size of 5×5 pixels. As the area of the platelet adhesion increases, the platelets plug the channel and there is only a small amount of blood flows. This image analysis could provide new insights for better understanding of the interactions between platelet aggregation and blood flows in various physiological conditions.

Keywords: platelet activation, correlation coefficient, image analysis, shear rate

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3783 Multichannel Object Detection with Event Camera

Authors: Rafael Iliasov, Alessandro Golkar

Abstract:

Object detection based on event vision has been a dynamically growing field in computer vision for the last 16 years. In this work, we create multiple channels from a single event camera and propose an event fusion method (EFM) to enhance object detection in event-based vision systems. Each channel uses a different accumulation buffer to collect events from the event camera. We implement YOLOv7 for object detection, followed by a fusion algorithm. Our multichannel approach outperforms single-channel-based object detection by 0.7% in mean Average Precision (mAP) for detection overlapping ground truth with IOU = 0.5.

Keywords: event camera, object detection with multimodal inputs, multichannel fusion, computer vision

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3782 Surgical Site Infections Post Ventriculoperitoneal (VP) Shunting: A Matched Healthcare Cost and Length of Stay Study

Authors: Issa M. Hweidi, Saba W. Al-Ibraheem

Abstract:

This study aimed to assess the increased hospital length of stay and healthcare costs associated with SSIs among ventriculoperitoneal shunting surgery patients in Jordan. This study adopted a retrospective and nested 1:1 matched case-control design. A non-probability convenient sample of 48 VP shunt patients was recruited for the purpose of the study. The targeted groups of the study basically used to cross-match the variables investigated to minimize the risk of confounding. Information was extracted from the text of patients' electronic health records. As compared to the non-SSI group, the SSI group had an extra mean healthcare cost of $13,696.53 (p=0.001) and longer hospital length of stay (22.64 mean additional days). Furthermore, Acinetobacter baumannii and Klebsiella pneumonia were identified as being the most predominant causative agents of SSIs. The results of this study may provide baseline data for national and regional benchmarking to evaluate the quality of care provided to likewise patients. Adherence to infection control strategies and protocols considering new surveillance methods of SSIs is encouraged.

Keywords: ventriculoperitoneal shunt, health care cost, length of stay, neurosurgery, surgical site infections

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3781 Spectrum Allocation Using Cognitive Radio in Wireless Mesh Networks

Authors: Ayoub Alsarhan, Ahmed Otoom, Yousef Kilani, Abdel-Rahman al-GHuwairi

Abstract:

Wireless mesh networks (WMNs) have emerged recently to improve internet access and other networking services. WMNs provide network access to the clients and other networking functions such as routing, and packet forwarding. Spectrum scarcity is the main challenge that limits the performance of WMNs. Cognitive radio is proposed to solve spectrum scarcity problem. In this paper, we consider a cognitive wireless mesh network where unlicensed users (secondary users, SUs) can access free spectrum that is allocated to spectrum owners (primary users, PUs). Although considerable research has been conducted on spectrum allocation, spectrum assignment is still considered an important challenging problem. This problem can be solved using cognitive radio technology that allows SUs to intelligently locate free bands and access them without interfering with PUs. Our scheme considers several heuristics for spectrum allocation. These heuristics include: channel error rate, PUs activities, channel capacity and channel switching time. Performance evaluation of the proposed scheme shows that the scheme is able to allocate the unused spectrum for SUs efficiently.

Keywords: cognitive radio, dynamic spectrum access, spectrum management, spectrum sharing, wireless mesh networks

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3780 Improving Axial-Attention Network via Cross-Channel Weight Sharing

Authors: Nazmul Shahadat, Anthony S. Maida

Abstract:

In recent years, hypercomplex inspired neural networks improved deep CNN architectures due to their ability to share weights across input channels and thus improve cohesiveness of representations within the layers. The work described herein studies the effect of replacing existing layers in an Axial Attention ResNet with their quaternion variants that use cross-channel weight sharing to assess the effect on image classification. We expect the quaternion enhancements to produce improved feature maps with more interlinked representations. We experiment with the stem of the network, the bottleneck layer, and the fully connected backend by replacing them with quaternion versions. These modifications lead to novel architectures which yield improved accuracy performance on the ImageNet300k classification dataset. Our baseline networks for comparison were the original real-valued ResNet, the original quaternion-valued ResNet, and the Axial Attention ResNet. Since improvement was observed regardless of which part of the network was modified, there is a promise that this technique may be generally useful in improving classification accuracy for a large class of networks.

Keywords: axial attention, representational networks, weight sharing, cross-channel correlations, quaternion-enhanced axial attention, deep networks

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3779 The Design of a Die for the Processing of Aluminum through Equal Channel Angular Pressing

Authors: P. G. F. Siqueira, N. G. S. Almeida, P. M. A. Stemler, P. R. Cetlin, M. T. P. Aguilar

Abstract:

The processing of metals through Equal Channel Angular Pressing (ECAP) leads to their remarkable strengthening. The ECAP dies control the amount of strain imposed on the material through its geometry, especially through the angle between the die channels, and thus the microstructural and mechanical properties evolution of the material. The present study describes the design of an ECAP die whose utilization and maintenance are facilitated, and that also controls the eventual undesired flow of the material during processing. The proposed design was validated through numerical simulations procedures using commercial software. The die was manufactured according to the present design and tested. Tests using aluminum alloys also indicated to be suitable for the processing of higher strength alloys.

Keywords: ECAP, mechanical design, numerical methods, SPD

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3778 Numerical Analysis of Real-Scale Polymer Electrolyte Fuel Cells with Cathode Metal Foam Design

Authors: Jaeseung Lee, Muhammad Faizan Chinannai, Mohamed Hassan Gundu, Hyunchul Ju

Abstract:

In this paper, we numerically investigated the effect of metal foams on a real scale 242.57cm2 (19.1 cm × 12.7 cm) polymer electrolyte membrane fuel cell (PEFCs) using a three-dimensional two-phase PEFC model to substantiate design approach for PEFCs using metal foam as the flow distributor. The simulations were conducted under the practical low humidity hydrogen, and air gases conditions in order to observe the detailed operation result in the PEFCs using the serpentine flow channel in the anode and metal foam design in the cathode. The three-dimensional contours of flow distribution in the channel, current density distribution in the membrane and hydrogen and oxygen concentration distribution are provided. The simulation results revealed that the use of highly porous and permeable metal foam can be beneficial to achieve a more uniform current density distribution and better hydration in the membrane under low inlet humidity conditions. This study offers basic directions to design channel for optimal water management of PEFCs.

Keywords: polymer electrolyte fuel cells, metal foam, real-scale, numerical model

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3777 Computational Insights Into Allosteric Regulation of Lyn Protein Kinase: Structural Dynamics and Impacts of Cancer-Related Mutations

Authors: Mina Rabipour, Elena Pallaske, Floyd Hassenrück, Rocio Rebollido-Rios

Abstract:

Protein tyrosine kinases, including Lyn kinase of the Src family kinases (SFK), regulate cell proliferation, survival, and differentiation. Lyn kinase has been implicated in various cancers, positioning it as a promising therapeutic target. However, the conserved ATP-binding pocket across SFKs makes developing selective inhibitors challenging. This study aims to address this limitation by exploring the potential for allosteric modulation of Lyn kinase, focusing on how its structural dynamics and specific oncogenic mutations impact its conformation and function. To achieve this, we combined homology modeling, molecular dynamics simulations, and data science techniques to conduct microsecond-length simulations. Our approach allowed a detailed investigation into the interplay between Lyn’s catalytic and regulatory domains, identifying key conformational states involved in allosteric regulation. Additionally, we evaluated the structural effects of Dasatinib, a competitive inhibitor, and ATP binding on Lyn active conformation. Notably, our simulations show that cancer-related mutations, specifically I364L/N and E290D/K, shift Lyn toward an inactive conformation, contrasting with the active state of the wild-type protein. This may suggest how these mutations contribute to aberrant signaling in cancer cells. We conducted a dynamical network analysis to assess residue-residue interactions and the impact of mutations on the Lyn intramolecular network. This revealed significant disruptions due to mutations, especially in regions distant from the ATP-binding site. These disruptions suggest potential allosteric sites as therapeutic targets, offering an alternative strategy for Lyn inhibition with higher specificity and fewer off-target effects compared to ATP-competitive inhibitors. Our findings provide insights into Lyn kinase regulation and highlight allosteric sites as avenues for selective drug development. Targeting these sites may modulate Lyn activity in cancer cells, reducing toxicity and improving outcomes. Furthermore, our computational strategy offers a scalable approach for analyzing other SFK members or kinases with similar properties, facilitating the discovery of selective allosteric modulators and contributing to precise cancer therapies.

Keywords: lyn tyrosine kinase, mutation analysis, conformational changes, dynamic network analysis, allosteric modulation, targeted inhibition

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3776 Dual-Channel Multi-Band Spectral Subtraction Algorithm Dedicated to a Bilateral Cochlear Implant

Authors: Fathi Kallel, Ahmed Ben Hamida, Christian Berger-Vachon

Abstract:

In this paper, a Speech Enhancement Algorithm based on Multi-Band Spectral Subtraction (MBSS) principle is evaluated for Bilateral Cochlear Implant (BCI) users. Specifically, dual-channel noise power spectral estimation algorithm using Power Spectral Densities (PSD) and Cross Power Spectral Densities (CPSD) of the observed signals is studied. The enhanced speech signal is obtained using Dual-Channel Multi-Band Spectral Subtraction ‘DC-MBSS’ algorithm. For performance evaluation, objective speech assessment test relying on Perceptual Evaluation of Speech Quality (PESQ) score is performed to fix the optimal number of frequency bands needed in DC-MBSS algorithm. In order to evaluate the speech intelligibility, subjective listening tests are assessed with 3 deafened BCI patients. Experimental results obtained using French Lafon database corrupted by an additive babble noise at different Signal-to-Noise Ratios (SNR) showed that DC-MBSS algorithm improves speech understanding for single and multiple interfering noise sources.

Keywords: speech enhancement, spectral substracion, noise estimation, cochlear impalnt

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3775 Effect of Pulmonary Rehabilitation towards Length of Stay and IL-6 Level on Community-Acquired Pneumonia Patients

Authors: Santony Santony, Teguh Rahayu Sartono, Iin Noor Chozin

Abstract:

Introduction: Pneumonia is acute inflammation on lung parenchyma which is caused by bacteria, virus, fungi, or parasite. In Indonesia, Pneumonia is among the ten inpatient cases. Length of stay is related to the increased morbidity rate, nosocomial infection, and costs. The aim of this study is to assess the effect of pulmonary rehabilitation on the difference in length of stay and the level of Interleukin 6 (IL-6) as an inflammation biomarker for community-acquired pneumonia (CAP) patients in non-intensive rooms. Therefore, pulmonary rehabilitation as adjunctive therapy can be routinely exercised in order to shorten the length of stay, along with the decrease in IL-6 level. Methods: This study was conducted from May to October 2019 at Saiful Anwar General Hospital, Malang. 40 community-acquired pneumonia patients in non-intensive rooms were divided into two groups. 20 patients in the treatment group and 20 patients in the control group, all of them were selected through both inclusion and exclusion criteria. This study used simple consecutive random sampling. In the treatment group, pulmonary rehabilitation performed was composed of breathing exercise, effective coughing technique, clapping (percussion), postural drainage, as well as respiratory muscle training using incentive spirometry device. Pulmonary rehabilitation was conducted twice over five days with a minimum duration of 15 minutes. Blood samples were taken both on the first and the fifth day of the treatment to measure IL-6 level as an inflammation biomarker. Result: For the treatment group, the length of stay was 5.35 days whereas the control group 7.6 days. It can be seen that the treatment group had a shorter length of stay by 2.25 days (P<0,001). The IL-6 level on the first day for the treatment group was 36.27 pg/ml, whereas on the fifth day was 34.36 pg/ml. There was a decrease in IL-6 level on the fifth day of treatment even though it was not statistically significant (P=0.628). IL-6 level on the control group for the first day was 67.76 pg/ml, and after the fifth day, the level decreased to 54.43 pg/ml. There seemed to be a decrease in the IL-6, but it was not statistically significant (P=0.502). On the fifth day, the treatment group showed an average IL-6 level of 34.36 pg/ml. This value was lower than that of the control group which did not receive pulmonary rehabilitation having an IL-6 level of 54.43 pg/ml, even though it was not statistically significant (p=0.221). Conclusion: This study concluded that pulmonary rehabilitation as an adjunctive therapy shortened length of stay by 2.25 days for community-acquired pneumonia patients in a non-intensive room. Both groups experienced a decrease in IL-6 level on the fifth day in comparison with the first day even though it was not statistically significant P>0,05. IL-6 level as an inflammation biomarker decreased on the fifth day of treatment which was in accordance with improvement on pneumonia patients.

Keywords: community-acquired pneumonia, interleukin-6, length of stay, pulmonary rehabilitation

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3774 Spectral Analysis Approaches for Simultaneous Determination of Binary Mixtures with Overlapping Spectra: An Application on Pseudoephedrine Sulphate and Loratadine

Authors: Sara El-Hanboushy, Hayam Lotfy, Yasmin Fayez, Engy Shokry, Mohammed Abdelkawy

Abstract:

Simple, specific, accurate and precise spectrophotometric methods are developed and validated for simultaneous determination of pseudoephedrine sulphate (PSE) and loratadine (LOR) in combined dosage form based on spectral analysis technique. Pseudoephedrine (PSE) in binary mixture could be analyzed either by using its resolved zero order absorption spectrum at its λ max 256.8 nm after subtraction of LOR spectrum or in presence of LOR spectrum by absorption correction method at 256.8 nm, dual wavelength (DWL) method at 254nm and 273nm, induced dual wavelength (IDWL) method at 256nm and 272nm and ratio difference (RD) method at 256nm and 262 nm. Loratadine (LOR) in the mixture could be analyzed directly at 280nm without any interference of PSE spectrum or at 250 nm using its recovered zero order absorption spectrum using constant multiplication(CM).In addition, simultaneous determination for PSE and LOR in their mixture could be applied by induced amplitude modulation method (IAM) coupled with amplitude multiplication (PM).

Keywords: dual wavelength (DW), induced amplitude modulation method (IAM) coupled with amplitude multiplication (PM), loratadine, pseudoephedrine sulphate, ratio difference (RD)

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3773 Studying the Effect of Froude Number and Densimetric Froude Number on Local Scours around Circular Bridge Piers

Authors: Md Abdullah Al Faruque

Abstract:

A very large percentage of bridge failures are attributed to scouring around bridge piers and this directly influences public safety. Experiments are carried out in a 12-m long rectangular open channel flume made of transparent tempered glass. A 300 mm thick bed made up of sand particles is leveled horizontally to create the test bed and a 50 mm hollow plastic cylinder is used as a model bridge pier. Tests are carried out with varying flow depths and velocities. Data points of various scour parameters such as scour depth, width, and length are collected based on different flow conditions and visual observations of changes in the stream bed downstream the bridge pier are also made as the scour progresses. Result shows that all three major flow characteristics (flow depth, Froude number and densimetric Froude number) have one way or other affect the scour profile.

Keywords: bridge pier scour, densimetric Froude number, flow depth, Froude number, sand

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3772 Game-Theory-Based on Downlink Spectrum Allocation in Two-Tier Networks

Authors: Yu Zhang, Ye Tian, Fang Ye Yixuan Kang

Abstract:

The capacity of conventional cellular networks has reached its upper bound and it can be well handled by introducing femtocells with low-cost and easy-to-deploy. Spectrum interference issue becomes more critical in peace with the value-added multimedia services growing up increasingly in two-tier cellular networks. Spectrum allocation is one of effective methods in interference mitigation technology. This paper proposes a game-theory-based on OFDMA downlink spectrum allocation aiming at reducing co-channel interference in two-tier femtocell networks. The framework is formulated as a non-cooperative game, wherein the femto base stations are players and frequency channels available are strategies. The scheme takes full account of competitive behavior and fairness among stations. In addition, the utility function reflects the interference from the standpoint of channels essentially. This work focuses on co-channel interference and puts forward a negative logarithm interference function on distance weight ratio aiming at suppressing co-channel interference in the same layer network. This scenario is more suitable for actual network deployment and the system possesses high robustness. According to the proposed mechanism, interference exists only when players employ the same channel for data communication. This paper focuses on implementing spectrum allocation in a distributed fashion. Numerical results show that signal to interference and noise ratio can be obviously improved through the spectrum allocation scheme and the users quality of service in downlink can be satisfied. Besides, the average spectrum efficiency in cellular network can be significantly promoted as simulations results shown.

Keywords: femtocell networks, game theory, interference mitigation, spectrum allocation

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3771 Population Structure of Europian Pond Turtles, Emys Orbicularis (Linnaeus, 1758) in Narta Lagoon (Vlora Bay, Albania)

Authors: Enerit Saçdanaku, Idriz Haxhiu

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In this study was monitored the population of the European Pond Turtle, Emys orbicularis (Linnaeus, 1758) in the area of Narta Lagoon, Vlora Bay (Albania), from August to October 2014. A total of 54 individuals of E. orbicularis were studied using different methodologies. Curved Carapace Length (CCL), Plastron Length (PL) and Curved Carapace Width (CCW) were measured for each individual of E. orbicularis and were statistically analyzed. All captured turtles were separated in seven different size–classes based on their carapace length (CCL). Each individual of E. orbicularis was marked by notching the carapace (marginal scutes). Form all individuals captured resulted that 37 were females (68.5%), 14 males (25.9%), 3 juveniles (5.5%), while 18 individuals of E. orbicularis were recaptured for the first and some for the second time.

Keywords: Emys orbicularis, female, juvenile, male, population, size–classes

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3770 Non-Steroidal Anti-inflammatory Drugs, Plant Extracts, and Characterized Microparticles to Modulate Antimicrobial Resistance of Epidemic Meca Positive S. Aureus of Dairy Origin

Authors: Amjad I. Aqib, Shanza R. Khan, Tanveer Ahmad, Syed A. R. Shah, Muhammad A. Naseer, Muhammad Shoaib, Iqra Sarwar, Muhammad F. A. Kulyar, Zeeshan A. Bhutta, Mumtaz A. Khan, Mahboob Ali, Khadija Yasmeen

Abstract:

The current study focused on resistance modulation of dairy linked epidemic mec A positive S. aureus for resistance modulation by plant extract (Eucalyptus globolus, Calotropis procera), NSAIDs, and star like microparticles. Zinc oxide {ZnO}c and {Zn (OH)₂} microparticles were synthesized by solvothermal method and characterized by calcination, X-ray diffraction (XRD), and scanning electron microscope (SEM). Plant extracts were prepared by the Soxhlet extraction method. The study found 34% of subclinical samples (n=200) positive for S. aureus from dairy milk having significant (p < 0.05) association of assumed risk factors with pathogen. The antimicrobial assay showed 55, 42, 41, and 41% of S. aureus resistant to oxacillin, ciprofloxacin, streptomycin, and enoxacin. Amoxicillin showed the highest percentage of increase in zone of inhibitions (ZOI) at 100mg of Calotropis procera extract (31.29%) followed by 1mg/mL (28.91%) and 10mg/mL (21.68%) of Eucalyptus globolus. Amoxicillin increased ZOI by 42.85, 37.32, 29.05, and 22.78% in combination with 500 ug/ml with each of diclofenac, aspirin, ibuprofen, and meloxicam, respectively. Fractional inhibitory concentration indices (FICIs) showed synergism of amoxicillin with diclofenac and aspirin and indifferent synergy with ibuprofen and meloxicam. The preliminary in vitro finding of combination of microparticles with amoxicillin proved to be synergistic, giving rise to 26.74% and 14.85% increase in ZOI of amoxicillin in combination with zinc oxide and zinc hydroxide, respectively. The modulated antimicrobial resistance incurred by NSAIDs, plant extracts, and microparticles against pathogenic S. aureus invite immediate attention to probe alternative antimicrobial sources.

Keywords: antimicrobial resistance, dairy milk, nanoparticles, NSIDs, plant extracts, resistance modulation, S. aureus

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3769 Strained Channel Aluminum Nitride/Gallium Nitride Heterostructures Homoepitaxially Grown on Aluminum Nitride-On-Sapphire Template by Plasma-Assisted Molecular Beam Epitaxy

Authors: Jiajia Yao, GuanLin Wu, Fang liu, JunShuai Xue, JinCheng Zhang, Yue Hao

Abstract:

Due to its outstanding material properties like high thermal conductivity and ultra-wide bandgap, Aluminum nitride (AlN) has the promising potential to provide high breakdown voltage and high output power among III-nitrides for various applications in electronics and optoelectronics. This work presents material growth and characterization of strained channel Aluminum nitride/Gallium nitride (AlN/GaN) heterostructures grown by plasma-assisted molecular beam epitaxy (PA-MBE) on AlN-on-sapphire templates. To improve the crystal quality and manifest the ability of the PA-MBE approach, a thick AlN buffer with a thickness of 180 nm is first grown on AlN template, which acts as a back-barrier to enhance the breakdown characteristic and isolates the leakage path existing in the interface between AlN epilayer and AlN template, as well as improve the heat dissipation. The grown AlN buffer features a root-mean-square roughness of 0.2 nm over a scanned area of 2×2 µm2 measured by atomic force microscopy (AFM), and exhibits full-width at half-maximum of 95 and 407 arcsec for the (002) and (102) plane the X-ray rocking curve, respectively, tested by high resolution x-ray diffraction (HR-XRD). With a thin and strained GaN channel, the electron mobility of 294 cm2 /Vs. with a carrier concentration of 2.82×1013 cm-2 at room temperature is achieved in AlN/GaN double-channel heterostructures, and the depletion capacitance is as low as 14 pF resolved by the capacitance-voltage, which indicates the promising opportunities for future applications in next-generation high temperature, high-frequency and high-power electronics with a further increased electron mobility by optimization of heterointerface quality.

Keywords: AlN/GaN, HEMT, MBE, homoepitaxy

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3768 Retrieving Iconometric Proportions of South Indian Sculptures Based on Statistical Analysis

Authors: M. Bagavandas

Abstract:

Introduction: South Indian stone sculptures are known for their elegance and history. They are available in large numbers in different monuments situated different parts of South India. These art pieces have been studied using iconography details, but this pioneering study introduces a novel method known as iconometry which is a quantitative study that deals with measurements of different parts of icons to find answers for important unanswered questions. The main aim of this paper is to compare iconometric measurements of the sculptures with canonical proportion to determine whether the sculptors of the past had followed any of the canonical proportions prescribed in the ancient text. If not, this study recovers the proportions used for carving sculptures which is not available to us now. Also, it will be interesting to see how these sculptural proportions of different monuments belonging to different dynasties differ from one another in terms these proportions. Methods and Materials: As Indian sculptures are depicted in different postures, one way of making measurements independent of size, is to decode on a suitable measurement and convert the other measurements as proportions with respect to the chosen measurement. Since in all canonical texts of Indian art, all different measurements are given in terms of face length, it is chosen as the required measurement for standardizing the measurements. In order to compare these facial measurements with measurements prescribed in Indian canons of Iconography, the ten facial measurements like face length, morphological face length, nose length, nose-to-chin length, eye length, lip length, face breadth, nose breadth, eye breadth and lip breadth were standardized using the face length and the number of measurements reduced to nine. Each measurement was divided by the corresponding face length and multiplied by twelve and given in angula unit used in the canonical texts. The reason for multiplying by twelve is that the face length is given as twelve angulas in the canonical texts for all figures. Clustering techniques were used to determine whether the sculptors of the past had followed any of the proportions prescribed in the canonical texts of the past to carve sculptures and also to compare the proportions of sculptures of different monuments. About one hundred twenty-seven stone sculptures from four monuments belonging to the Pallava, the Chola, the Pandya and the Vijayanagar dynasties were taken up for this study. These art pieces belong to a period ranging from the eighth to the sixteenth century A.D. and all of them adorning different monuments situated in different parts of Tamil Nadu State, South India. Anthropometric instruments were used for taking measurements and the author himself had measured all the sample pieces of this study. Result: Statistical analysis of sculptures of different centers of art from different dynasties shows a considerable difference in facial proportions and many of these proportions differ widely from the canonical proportions. The retrieved different facial proportions indicate that the definition of beauty has been changing from period to period and region to region.

Keywords: iconometry, proportions, sculptures, statistics

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3767 Cadaveric Assessment of Kidney Dimensions Among Nigerians - A Preliminary Report

Authors: Rotimi Sunday Ajani, Omowumi Femi-Akinlosotu

Abstract:

Background: The usually paired human kidneys are retroperitoneal urinary organs with some endocrine functions. Standard text books of anatomy ascribe single value to each of the dimension of length, width and thickness. Research questions: These values do not give consideration to racial and genetic variability in human morphology. They may thus be erroneous to students and clinicians working on Nigerians. Objectives: The study aimed at establishing reference values of the kidney length, width and thickness for Nigerians using the cadaveric model. Methodology: The length, width, thickness and weight of sixty kidneys harvested from cadavers of thirty adult Nigerians (Male: Female; 27: 3) were measured. Respective volume was calculated using the ellipsoid formula. Results: The mean length of the kidney was 9.84±0.89 cm (9.63±0.88 {right}; 10.06±0.86 {left}), width- 5.18±0.70 cm (5.21±0.72 {right}; 5.14±0.70 {left}), thickness-3.45±0.56 cm (3.36±0.58 {right}, 3.53±0.55 {left}), weight-125.06±22.34 g (122.36±21.70 {right}; 127.76 ±24.02 {left}) and volume of 95.45± 24.40 cm3 (91.73± 26.84 {right}; 99.17± 25.75 {left}). Discussion: Though the values of the parameters measured were higher for the left kidney (except for the width), they were not statistically significant. The various parameters obtained by this study differ from those of similar studies from other continents. Conclusion: Stating single value for each of the parameter of length, width and thickness of the kidney as currently obtained in textbooks of anatomy may be incomplete information and hence misleading. Thus, there is the need to emphasize racial differences when stating the normal values of kidney dimensions in textbooks of anatomy. Implication for Research and Innovation: The results of the study showed the dimensions of the kidney (length, width and thickness) have interracial vagaries as they were different from those of similar studies and values stated in standard textbooks of human anatomy. Future direction: This is a preliminary report and the study will continue so that more data will be obtained.

Keywords: kidney dimensions, cadaveric estimation, adult nigerians, racial differences

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3766 Low Probability of Intercept (LPI) Signal Detection and Analysis Using Choi-Williams Distribution

Authors: V. S. S. Kumar, V. Ramya

Abstract:

In the modern electronic warfare, the signal scenario is changing at a rapid pace with the introduction of Low Probability of Intercept (LPI) radars. In the modern battlefield, radar system faces serious threats from passive intercept receivers such as Electronic Attack (EA) and Anti-Radiation Missiles (ARMs). To perform necessary target detection and tracking and simultaneously hide themselves from enemy attack, radar systems should be LPI. These LPI radars use a variety of complex signal modulation schemes together with pulse compression with the aid of advancement in signal processing capabilities of the radar such that the radar performs target detection and tracking while simultaneously hiding enemy from attack such as EA etc., thus posing a major challenge to the ES/ELINT receivers. Today an increasing number of LPI radars are being introduced into the modern platforms and weapon systems so these LPI radars created a requirement for the armed forces to develop new techniques, strategies and equipment to counter them. This paper presents various modulation techniques used in generation of LPI signals and development of Time Frequency Algorithms to analyse those signals.

Keywords: anti-radiation missiles, cross terms, electronic attack, electronic intelligence, electronic warfare, intercept receiver, low probability of intercept

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3765 Laboratory Model Tests on Encased Group Columns

Authors: Kausar Ali

Abstract:

There are several ground treatment techniques which may meet the twin objectives of increasing the bearing capacity with simultaneous reduction of settlements, but the use of stone columns is one of the most suited techniques for flexible structures such as embankments, oil storage tanks etc. that can tolerate some settlement and used worldwide. However, when the stone columns in very soft soils are loaded; stone columns undergo excessive settlement due to low lateral confinement provided by the soft soil, leading to the failure of the structure. The poor performance of stone columns under these conditions can be improved by encasing the columns with a suitable geosynthetic. In this study, the effect of reinforcement on bearing capacity of composite soil has been investigated by conducting laboratory model tests on floating and end bearing long stone columns with l/d ratio of 12. The columns were reinforced by providing geosynthetic encasement over varying column length (upper 25%, 50%, 75%, and 100% column length). In this study, a group of columns has been used instead of single column, because in the field, columns used for the purpose always remain in groups. The tests indicate that the encasement over the full column length gives higher failure stress as compared to the encasement over the partial column length for both floating and end bearing long columns. The performance of end-bearing columns was found much better than the floating columns.

Keywords: geosynthetic, ground improvement, soft clay, stone column

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3764 Reducing Total Harmonic Content of 9-Level Inverter by Use of Cuckoo Algorithm

Authors: Mahmoud Enayati, Sirous Mohammadi

Abstract:

In this paper, a novel procedure to find the firing angles of the multilevel inverters of supply voltage and, consequently, to decline the total harmonic distortion (THD), has been presented. In order to eliminate more harmonics in the multilevel inverters, its number of levels can be lessened or pulse width modulation waveform, in which more than one switching occur in each level, be used. Both cases complicate the non-algebraic equations and their solution cannot be performed by the conventional methods for the numerical solution of nonlinear equations such as Newton-Raphson method. In this paper, Cuckoo algorithm is used to compute the optimal firing angle of the pulse width modulation voltage waveform in the multilevel inverter. These angles should be calculated in such a way that the voltage amplitude of the fundamental frequency be generated while the total harmonic distortion of the output voltage be small. The simulation and theoretical results for the 9-levels inverter offer the high applicability of the proposed algorithm to identify the suitable firing angles for declining the low order harmonics and generate a waveform whose total harmonic distortion is very small and it is almost a sinusoidal waveform.

Keywords: evolutionary algorithms, multilevel inverters, total harmonic content, Cuckoo Algorithm

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3763 Investigation of the Thermal Flow inside the Catalytic Combustor for Lean CH4-Air Mixture on a Platinum Catalyst with H2 Addition

Authors: Kumaresh Selvakumar, Man Young Kim

Abstract:

In order to elaborate the main idea of investigating the flow physics inside the catalytic combustor, the characteristics of the catalytic surface reactions are analyzed by employing the CHEMKIN methodology with detailed gas and surface chemistries. The presence of a catalyst inside an engine enables complete combustion at lower temperatures which promotes desired chemical reactions. A single channel from the honeycomb monolith catalytic combustor is preferred to analyze the gas and surface reactions in the catalyst bed considering the fact that every channel in the honeycomb monolith behaves in similar fashion. The simplified approach with single catalyst channel using plug flow reactor can be used to predict the flow behavior inside the catalytic combustor. The hydrogen addition to the combustion reactants offers a way to light-off catalytic combustion of methane on platinum catalyst and aids to reduce the surface ignition temperature. Indeed, the hydrogen adsorption is higher on the uncovered Pt(s) surface sites because the sticking coefficient of hydrogen is larger than that of methane. The location of flame position in the catalyst bed is validated by igniting the methane fuel with the presence of hydrogen for corresponding multistep surface reactions.

Keywords: catalytic combustor, hydrogen adsorption, plug flow reactor, surface ignition temperature

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3762 Sedimentation and Morphology of the Kura River-Deltaic System in the Southern Caucasus under Anthropogenic and Sea-Level Controls

Authors: Elmira Aliyeva, Dadash Huseynov, Robert Hoogendoorn, Salomon Kroonenberg

Abstract:

The Kura River is the major water artery in the Southern Caucasus; it is a third river in the Caspian Sea basin in terms of length and size of the catchment area, the second in terms of the water budget, and the first in the volume of sediment load. Understanding of major controls on the Kura fluvial- deltaic system is valuable for efficient management of the highly populated river basin and coastal zone. We have studied grain size of sediments accumulated in the river channels and delta and dated by 210Pb method, astrophotographs, old topographic and geological maps, and archive data. At present time sediments are supplied by the Kura River to the Caspian Sea through three distributary channels oriented north-east, south-east, and south-west. The river is dominated by the suspended load - mud, silt, very fine sand. Coarse sediments are accumulated in the distributaries, levees, point bar, and delta front. The annual suspended sediment budget in the time period 1934-1952 before construction of the Mingechavir water reservoir in 1953 in the Kura River midstream area was 36 mln.t/yr. From 1953 to 1964, the suspended load has dropped to 12 mln.t/yr. After regulation of the Kura River discharge the volume of suspended load transported via north-eastern channel reduced from 35% of the total sediment amount to 4%, and through the main south-eastern channel increased from 65% to 96% with further fall to 56% due to creation of new south-western channel in 1964. Between 1967-1976 the annual sediment budget of the Kura River reached 22,5 mln. t/yr. From 1977 to 1986, the sediment load carried by the Kura River dropped to 17,6 mln.t/yr. The historical data show that between 1860 and 1907, during relatively stable Caspian Sea level two channels - N and SE, appear to have distributed an equal amount of sediments as seen from the bilateral geometry of the delta. In the time period 1907-1929, two new channels - E and NE, appeared. The growth of three delta lobes - N, NE, and SE, and rapid progradation of the delta has occurred on the background of the Caspian Sea level rise as a result of very high sediment supply. Since 1929 the Caspian Sea level decline was followed by the progradation of the delta occurring along the SE channel. The eastern and northern channels have been silted up. The slow rate of progradation at its initial stage was caused by the artificial reduction in the sediment budget. However, the continuous sea-level fall has brought to this river bed gradient increase, high erosional rate, increase in the sediment supply, and more rapid progradation. During the subsequent sea-level rise after 1977 accompanied by the decrease in the sediment budget, the southern part of the delta has turned into a complex of small, shallow channels oriented to the south. The data demonstrate that behaviour of the Kura fluvial – deltaic system and variations in the sediment budget besides anthropogenic regulation are strongly governed by the Caspian Sea level very rapid changes.

Keywords: anthropogenic control on sediment budget, Caspian sea-level variations, Kura river sediment load, morphology of the Kura river delta, sedimentation in the Kura river delta

Procedia PDF Downloads 153
3761 Establishment of Bit Selective Mode Storage Covert Channel in VANETs

Authors: Amarpreet Singh, Kimi Manchanda

Abstract:

Intended for providing the security in the VANETS (Vehicular Ad hoc Network) scenario, the covert storage channel is implemented through data transmitted between the sender and the receiver. Covert channels are the logical links which are used for the communication purpose and hiding the secure data from the intruders. This paper refers to the Establishment of bit selective mode covert storage channels in VANETS. In this scenario, the data is being transmitted with two modes i.e. the normal mode and the covert mode. During the communication between vehicles in this scenario, the controlling of bits is possible through the optional bits of IPV6 Header Format. This implementation is fulfilled with the help of Network simulator.

Keywords: covert mode, normal mode, VANET, OBU, on-board unit

Procedia PDF Downloads 365