Search results for: virtual crack closure technique
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8266

Search results for: virtual crack closure technique

946 Kirigami Designs for Enhancing the Electromechanical Performance of E-Textiles

Authors: Braden M. Li, Inhwan Kim, Jesse S. Jur

Abstract:

One of the fundamental challenges in the electronic textile (e-textile) industry is the mismatch in compliance between the rigid electronic components integrated onto soft textile platforms. To address these problems, various printing technologies using conductive inks have been explored in an effort to improve the electromechanical performance without sacrificing the innate properties of the printed textile. However, current printing methods deposit densely layered coatings onto textile surfaces with low through-plane wetting resulting in poor electromechanical properties. This work presents an inkjet printing technique in conjunction with unique Kirigami cut designs to address these issues for printed smart textiles. By utilizing particle free reactive silver inks, our inkjet process produces conformal and micron thick silver coatings that surround individual fibers of the printed smart textile. This results in a highly conductive (0.63 Ω sq-1) printed e-textile while also maintaining the innate properties of the textile material including stretchability, flexibility, breathability and fabric hand. Kirigami is the Japanese art of paper cutting. By utilizing periodic cut designs, Kirigami imparts enhanced flexibility and delocalization of stress concentrations. Kirigami cut design parameters (i.e., cut spacing and length) were correlated to both the mechanical and electromechanical properties of the printed textiles. We demonstrate that designs using a higher cut-out ratio exponentially softens the textile substrate. Thus, our designs achieve a 30x improvement in the overall stretchability, 1000x decrease in elastic modulus, and minimal resistance change over strain regimes of 100-200% when compared to uncut designs. We also show minimal resistance change of our Kirigami inspired printed devices after being stretched to 100% for 1000 cycles. Lastly, we demonstrate a Kirigami-inspired electrocardiogram (ECG) monitoring system that improves stretchability without sacrificing signal acquisition performance. Overall this study suggests fundamental parameters affecting the performance of e-textiles and their scalability in the wearable technology industry

Keywords: kirigami, inkjet printing, flexible electronics, reactive silver ink

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945 Community-Based Assessment Approach to Empower Child with Disabilities: Institutional Study on Deaf Art Community in Yogyakarta, Indonesia

Authors: Mukhamad Fatkhullah, Arfan Fadli, Marini Kristina Situmeang, Siti Hazar Sitorus

Abstract:

The emergence of a community of people with disabilities along with the various works produced has made great progress to open the public eye to their existence in society. This study focuses attention on a community that is suspected to be one of the pioneers in pursuing the movement. It is Deaf Art Community (DAC), a community of persons with disabilities based in Yogyakarta, with deaf and speech-impaired members who use sign language in everyday communication. Knowing the movement of disabled communities is a good thing, the description of the things behind it then important to know as the basis for initiating similar movements. This research focuses on the question of how community of people with disabilities begin to take shape in different regions and interact with collaborative events. Qualitative method with in-depth interview as data collection techniques was used to describe the process of formation and the emergence of community. The analytical unit in the study initially focuses on the subject in the community, but in the process, it develops to institutional analysis. Therefore some informants were determined purposively and expanded using the snowball technique. The theory used in this research is Phenomenology of Alfred Schutz to be able to see reality from the subject and institutional point of view. The results of this study found that the community is formed because the existing educational institutions (both SLB and inclusion) are less able to empower and make children with disabilities become equal with the society. Through the SLB, the presence of children with disabilities becomes isolated from the society, especially in children of his or her age. Therefore, discrimination and labeling will never be separated from society's view. Meanwhile, facilities for the basic needs of children with disabilities can not be fully provided. Besides that, the guarantee of discrimination, glances, and unpleasant behavior from children without disability does not exist, which then indicates that the existing inclusion schools offer only symbolic acceptance. Thus, both in SLB and Inclusive Schools can not empower children with disabilities. Community-based assistance, in this case, has become an alternative to actually empowering children with disabilities. Not only giving them a place to interact, through the same community, children with disabilities will be guided to discover their talents and develop their potential to be self-reliant in the future.

Keywords: children with disabilities, community-based assessment, community empowerment, social equity

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944 A Differential Detection Method for Chip-Scale Spin-Exchange Relaxation Free Atomic Magnetometer

Authors: Yi Zhang, Yuan Tian, Jiehua Chen, Sihong Gu

Abstract:

Chip-scale spin-exchange relaxation free (SERF) atomic magnetometer makes use of millimeter-scale vapor cells micro-fabricated by Micro-electromechanical Systems (MEMS) technique and SERF mechanism, resulting in the characteristics of high spatial resolution and high sensitivity. It is useful for biomagnetic imaging including magnetoencephalography and magnetocardiography. In a prevailing scheme, circularly polarized on-resonance laser beam is adapted for both pumping and probing the atomic polarization. And the magnetic-field-sensitive signal is extracted by transmission laser intensity enhancement as a result of atomic polarization increase on zero field level crossing resonance. The scheme is very suitable for integration, however, the laser amplitude modulation (AM) noise and laser frequency modulation to amplitude modulation (FM-AM) noise is superimposed on the photon shot noise reducing the signal to noise ratio (SNR). To suppress AM and FM-AM noise the paper puts forward a novel scheme which adopts circularly polarized on-resonance light pumping and linearly polarized frequency-detuning laser probing. The transmission beam is divided into transmission and reflection beams by a polarization analyzer, the angle between the analyzer's transmission polarization axis and frequency-detuning laser polarization direction is set to 45°. The magnetic-field-sensitive signal is extracted by polarization rotation enhancement of frequency-detuning laser which induces two beams intensity difference increase as the atomic polarization increases. Therefore, AM and FM-AM noise in two beams are common-mode and can be almost entirely canceled by differential detection. We have carried out an experiment to study our scheme. The experiment reveals that the noise in the differential signal is obviously smaller than that in each beam. The scheme is promising to be applied for developing more sensitive chip-scale magnetometer.

Keywords: atomic magnetometer, chip scale, differential detection, spin-exchange relaxation free

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943 Determinants of Post-Psychotic Depression in Schizophrenia Patients in ACSH and Mekellle Hospital Tigray, Ethiopia, 2019

Authors: Ashenafi Ayele, Shewit Haftu, Tesfalem Araya

Abstract:

Background: “Post-psychotic depression”, “post schizophrenic depression”, and “secondary depression” have been used to describe the occurrence of depressive symptoms during the chronic phase of schizophrenia. Post-psychotic depression is the most common cause of death due to suicide in schizophrenia patients. Overall lifetime risk for patients with schizophrenia is 50% for suicide attempts and 9-13% lifetime risk for completed suicide and also it is associated with poor prognosis and poor quality of life. Objective: To assess determinant of post psychotic depression in schizophrenia patients ACSH and Mekelle General Hospital, Tigray Ethiopia 2019. Methods: An institutional based unmatched case control study was conducted among 69 cases and 138 controls with the ratio of case to control 1 ratio 2. The sample is calculated using epi-info 3.1 to assess the determinant factors of post-psychotic depression in schizophrenia patients. The cases were schizophrenia patients who have been diagnosed at least for more than one-year stable for two months, and the controls are any patients who are diagnosed as schizophrenia patients. Study subjects were selected using a consecutive sampling technique. The Calgary depression scale for schizophrenia self-administered questionnaire was used. Before the interview, it was assessed the client’s capacity to give intended information using a scale called the University of California, San Diego Brief Assessment of Capacity to Consent (UBACC). Bivariant and multiple Logistic regression analysis was performed to determine between the independent and dependent variables. The significant independent predictor was declared at 95% confidence interval and P-value of less than 0.05. Result: Females were affected by post psychotic depression with the (AOR=2.01, 95%CI: 1.003- 4.012, P= 0.49).Patients who have mild form of positive symptom of schizophrenia affected by post psychotic depression with (AOR =4.05, 95%CI: 1.888- 8.7.8, P=0001).Patients who have minimal form of negative symptom of schizophrenia are affected by post psychotic depression with (AOR =4.23, 95%CI: 1.081-17.092, P=.038). Conclusion: In this study, sex (female) and presence of positive and negative symptoms of schizophrenia were significantly associated. It is recommended that the post psychotic depression should be assessed in every schizophrenia patient to decrease the severity of illness, and to improve patient’s quality of life.

Keywords: determinants, post-psychotic depression, Mekelle city

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942 The Tradition of Drinking Tuak in Batak Society againts the Law of Alcohol Usage in Indonesia

Authors: Siti Hazar Sitorus, Marini Kristina Situmeang, Mukhammad Fatkhullah, Arfan Fadli

Abstract:

This study aims to examine how the Batak tribe in the Village Lumban Sitorus Parmaksian District, Toba Samosir (Tobasa) interpret the culture of drinking Tuak as a social interaction. This research uses qualitative method with case study approach. Through this approach, the researchers obtained primary data by looking at and observing the social interaction that occurs when the activity of drinking tuak takes place on the daily life of the Batak Toba community in the village of Lumban Sitorus. The technique of data collecting is done by observation and in-depth interview. This study focuses on Batak Toba community, especially men who daily drink tuak. The results obtained from this study is Batak Toba society has a habit of drinking Tuak (a type of alcoholic beverage derived from water sapphire juice that is fermented). In Batak Toba society, tuak is not only considered as an alcoholic drink which is usually drunk in the afternoon at lapotuak (tuak shop), but tuak is also understood as a drink of honor in a traditional party at Toba Batak society. On the other hand, the activity of drinking of tuak was also considered as a medium or a means of connecting the formation of a sense of solidarity among the people of LumbanSitorous Village. In its existence, drinking tuak is defined as a mean that can facilitate the establishment to open communication with fellow members of Batak Toba community, such as at leisure, birth party, death or as medicine. Specifically, tuak in a special sense in Batak Toba society is also a symbol of intimacy, gratitude, and respect which is manifested in the activity of daily drinking tuak. In Indonesia, if we refer to the Criminal Code in articles 300 and 536 it is clear that whoever intentionally sells and consumes intoxicating / alcoholic drinks will be subject to a maximum jail term of one year. It became interesting then when looking at Indonesia as a country that has a diversity of cultures in which the law implies the prohibition of alcoholic / intoxicating beverages. However, the existence of drinking of tuak as a drink that categorized intoxicating in Batak Toba society still continues to.

Keywords: tradition of drinking tuak, meaning of tuak, Batak society, cultural studies

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941 White-Rot Hymenomycetes as Oil Palm Log Treatments: Accelerating Biodegradation of Basal Stem Rot-Affected Oil Palm Stumps

Authors: Yuvarani Naidu, Yasmeen Siddiqui, Mohd Yusof Rafii , Abu Seman Idris

Abstract:

Sustainability of oil palm production in Southeast Asia, especially in Indonesia and Malaysia, is jeopardized by Ganoderma boninense, the fungus which causes basal stem rot (BSR) in oil palm. The root contact with unattended infected debris left in the plantations during replanting is known to be the primary source of inoculum. Abiding by the law, potentially effective technique of managing Ganoderma infected oil palm debris is deemed necessary because of the zero-burning policy in Malaysian oil palm plantations. White-rot hymenomycetes antagonistic to Ganoderma sp were selected to test their efficacy as log treatments in degrading Ganoderma infected oil palm logs and to minimize the survival of Ganoderma inoculum. Decay rate in terms of mass loss was significantly higher after the application of solid-state cultivation (SSC) of Trametes lactinea FBW (64% ±1.2), followed by Pycnoporus sanguineus FBR (55% ±1.7) in infected log block tissues, after 10 months of treatments. The degradation pattern was clearly distinguished between the treated and non-treated log blocks with the developed SSC formulations. The control infected log blocks showed the highest, whereas infected log blocks treated with either P. sanguineus FBR or T. lactinea FBW SSC formulations exhibited statistically lowest number of Ganoderma spp. recovery on Ganoderma Selective Medium (GSM), after 8 months of treatment. Out of that, the lowest recovery of Ganoderma spp. was reported in infected log blocks inoculated with the strain T. lactinea FBW (21% ± 0.9) followed by P. sanguineus FBR (33% ± 2.2), after 8 months, Further, no recovery of Ganoderma was noticeable, 10 months after treatment applications in log blocks treated with both of the formulations. This is the first nursery-base study to substantiate the initial colonization of white-rot hymenomycetes on oil palm log blocks previously infected with BSR pathogen, G. boninense. The present study has indicated that log blocks treatment with white-rot hymenomycetes significantly affected the mass loss of diseased and healthy log block tissues. This study provides a basis of biotechnological approaches inefficient degradation of oil palm-generated crop debris, under natural conditions with an ultimate aim of reducing the Ganoderma inoculum under heavy BSR infection pressure in eco-friendly manner.

Keywords: basal stem rot disease, ganoderma boninense, oil palm, white-rot fungi

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940 An Agile, Intelligent and Scalable Framework for Global Software Development

Authors: Raja Asad Zaheer, Aisha Tanveer, Hafza Mehreen Fatima

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Global Software Development (GSD) is becoming a common norm in software industry, despite of the fact that global distribution of the teams presents special issues for effective communication and coordination of the teams. Now trends are changing and project management for distributed teams is no longer in a limbo. GSD can be effectively established using agile and project managers can use different agile techniques/tools for solving the problems associated with distributed teams. Agile methodologies like scrum and XP have been successfully used with distributed teams. We have employed exploratory research method to analyze different recent studies related to challenges of GSD and their proposed solutions. In our study, we had deep insight in six commonly faced challenges: communication and coordination, temporal differences, cultural differences, knowledge sharing/group awareness, speed and communication tools. We have established that each of these challenges cannot be neglected for distributed teams of any kind. They are interlinked and as an aggregated whole can cause the failure of projects. In this paper we have focused on creating a scalable framework for detecting and overcoming these commonly faced challenges. In the proposed solution, our objective is to suggest agile techniques/tools relevant to a particular problem faced by the organizations related to the management of distributed teams. We focused mainly on scrum and XP techniques/tools because they are widely accepted and used in the industry. Our solution identifies the problem and suggests an appropriate technique/tool to help solve the problem based on globally shared knowledgebase. We can establish a cause and effect relationship using a fishbone diagram based on the inputs provided for issues commonly faced by organizations. Based on the identified cause, suitable tool is suggested, our framework suggests a suitable tool. Hence, a scalable, extensible, self-learning, intelligent framework proposed will help implement and assess GSD to achieve maximum out of it. Globally shared knowledgebase will help new organizations to easily adapt best practices set forth by the practicing organizations.

Keywords: agile project management, agile tools/techniques, distributed teams, global software development

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939 Efficacy Of Tranexamic Acid On Blood Loss After Primary Total Hip Replacement : A Case-control Study In 154 Patients

Authors: Fedili Benamar, Belloulou Mohamed Lamine, Ouahes Hassane, Ghattas Samir

Abstract:

Introduction: Perioperative blood loss is a frequent cause of complications in total hip replacement (THR). The present prospective study assessed the efficacy of tranexamic acid (Exacyl(®)) in reducing blood loss in primary THR. Hypothesis: Tranexamic acid reduces blood loss in THR. Material and method: -This is a prospective randomized study on the effectiveness of Exacyl (tranexamic acid) in total hip replacement surgery performed on a standardized technique between 2019 and September 2022. -It involved 154 patients, of which 84 received a single injection of Exacyl (group 1) at a dosage of 10 mg/kg over 20 minutes during the perioperative period. -All patients received postoperative thromboprophylaxis with enoxaparin 0.4 ml subcutaneously. -All patients were admitted to the post-interventional intensive care unit for a duration of 24 hours for monitoring and pain management as per the service protocol. Results: 154 patients, of which 84 received a single injection of Exacyl (group 1) and 70 patients patients who did not receive Exacyl perioperatively : (Group 2 ) The average age is 57 +/- 15 years The distribution by gender was nearly equal with 56% male and 44% female; "The distribution according to the ASA score was as follows: 20.2% ASA1, 82.3% ASA2, and 17.5% ASA3. "There was a significant difference in the average volume of intraoperative and postoperative bleeding during the 48 hours." The average bleeding volume for group 1 (received Exacyl) was 614 ml +/- 228, while the average bleeding volume for group 2 was 729 +/- 300, with a chi-square test of 6.35 and a p-value < 0.01, which is highly significant. The ANOVA test showed an F-statistic of 7.11 and a p-value of 0.008. A Bartlett test revealed a chi-square of 6.35 and a p-value < 0.01." "In Group 1 (patients who received Exacyl), 73% had bleeding less than 750 ml (Group A), and 26% had bleeding exceeding 750 ml (Group B). In Group 2 (patients who did not receive Exacyl perioperatively), 52% had bleeding less than 750 ml (Group A), and 47% had bleeding exceeding 750 ml (Group B). "Thus, the use of Exacyl reduced perioperative bleeding and specifically decreased the risk of severe bleeding exceeding 750 ml by 43% with a relative risk (RR) of 1.37 and a p-value < 0.01. The transfusion rate was 1.19% in the population of Group 1 (Exacyl), whereas it was 10% in the population of Group 2 (no Exacyl). It can be stated that the use of Exacyl resulted in a reduction in perioperative blood transfusion with an RR of 0.1 and a p-value of 0.02. Conclusions: The use of Exacyl significantly reduced perioperative bleeding in this type of surgery.

Keywords: acid tranexamic, blood loss, anesthesia, total hip replacement, surgery

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938 Materials and Techniques of Anonymous Egyptian Polychrome Cartonnage Mummy Mask: A Multiple Analytical Study

Authors: Hanaa A. Al-Gaoudi, Hassan Ebeid

Abstract:

The research investigates the materials and processes used in the manufacturing of an Egyptian polychrome cartonnage mummy mask with the aim of dating this object and establishing trade patterns of certain materials that were used and available at the time of ancient Egypt. This anonymous-source object was held in the basement storage of the Egyptian Museum in Cairo (EMC) and has never been on display. Furthermore, there is no information available regarding its owner, provenance, date, and even the time of its possession by the museum. Moreover, the object is in a very poor condition where almost two-thirds of the mask was bent and has never received any previous conservation treatment. This research has utilized well-established multi-analytical methods to identify the considerable diversity of materials that have been used in the manufacturing of this object. These methods include Computed Tomography Scan (CT scan) to acquire detailed pictures of the inside physical structure and condition of the bended layers. Dino-Lite portable digital microscope, scanning electron microscopy with energy dispersive X-ray spectrometer (SEM-EDX), and the non-invasive imaging technique of multispectral imaging (MSI) to obtain information about the physical characteristics and condition of the painted layers and to examine the microstructure of the materials. Portable XRF Spectrometer (PXRF) and X-Ray powder diffraction (XRD) to identify mineral phases and the bulk element composition in the gilded layer, ground, and pigments; Fourier-transform infrared (FTIR) to identify organic compounds and their molecular characterization; accelerator mass spectrometry (AMS 14C) to date the object. Preliminary results suggest that there are no human remains inside the object, and the textile support is linen fibres with tabby weave 1/1 and these fibres are in a very bad condition. Several pigments have been identified, such as Egyptian blue, Magnetite, Egyptian green frit, Hematite, Calcite, and Cinnabar; moreover, the gilded layers are pure gold and the binding media in the pigments is Arabic gum and animal glue in the textile support layer.

Keywords: analytical methods, Egyptian museum, mummy mask, pigments, textile

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937 The Use of a Novel Visual Kinetic Demonstration Technique in Student Skill Acquisition of the Sellick Cricoid Force Manoeuvre

Authors: L. Nathaniel-Wurie

Abstract:

The Sellick manoeuvre a.k.a the application of cricoid force (CF), was first described by Brian Sellick in 1961. CF is the application of digital pressure against the cricoid cartilage with the intention of posterior force causing oesophageal compression against the vertebrae. This is designed to prevent passive regurgitation of gastric contents, which is a major cause of morbidity and mortality during emergency airway management inside and outside of the hospital. To the authors knowledge, there is no universally standardised training modality and, therefore, no reliable way to examine if there are appropriate outcomes. If force is not measured during training, how can one surmise that appropriate, accurate, or precise amounts of force are being used routinely. Poor homogeneity in teaching and untested outcomes will correlate with reduced efficacy and increased adverse effects. For this study, the accuracy of force delivery in trained professionals was tested, and outcomes contrasted against a novice control and a novice study group. In this study, 20 operating department practitioners were tested (with a mean experience of 5.3years of performing CF). Subsequent contrast with 40 novice students who were randomised into one of two arms. ‘Arm A’ were explained the procedure, then shown the procedure then asked to perform CF with the corresponding force measurement being taken three times. Arm B had the same process as arm A then before being tested, they had 10, and 30 Newtons applied to their hands to increase intuitive understanding of what the required force equated to, then were asked to apply the equivalent amount of force against a visible force metre and asked to hold that force for 20 seconds which allowed direct visualisation and correction of any over or under estimation. Following this, Arm B were then asked to perform the manoeuvre, and the force generated measured three times. This study shows that there is a wide distribution of force produced by trained professionals and novices performing the procedure for the first time. Our methodology for teaching the manoeuvre shows an improved accuracy, precision, and homogeneity within the group when compared to novices and even outperforms trained practitioners. In conclusion, if this methodology is adopted, it may correlate with higher clinical outcomes, less adverse events, and more successful airway management in critical medical scenarios.

Keywords: airway, cricoid, medical education, sellick

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936 Low-Surface Roughness and High Optical Quality CdS Thin Film Deposited on Heated Substrate Using Room-Temperature Chemical Solution

Authors: A. Elsayed, M. H. Dewaidar, M. Ghali, M. Elkemary

Abstract:

The high production cost of the conventional solar cells requires the search for economic methods suitable for solar energy conversion. Cadmium Sulfide (CdS) is one of the most important semiconductors used in photovoltaics, especially in large area solar cells; and can be prepared in a thin film form by a wide variety of deposition techniques. The preparation techniques include vacuum evaporation, sputtering and molecular beam epitaxy. Other techniques, based on chemical solutions, are also used for depositing CdS films with dramatically low-cost compared to other vacuum-based methods. Although this technique is widely used during the last decades, due to simplicity and low-deposition temperature (~100°C), there is still a strong need for more information on the growth process and its relation with the quality of the deposited films. Here, we report on deposition of high-quality CdS thin films; with low-surface roughness ( < 3.0 nm) and sharp optical absorption edge; on low-temperature glass substrates (70°C) using a new method based on the room-temperature chemical solution. In this method, a mixture solution of cadmium acetate and thiourea at room temperature was used under special growth conditions for deposition of CdS films. X-ray diffraction (XRD) measurements were used to examine the crystal structure properties of the deposited CdS films. In addition, UV-VIS transmittance and low-temperature (4K) photoluminescence (PL) measurements were performed for quantifying optical properties of the deposited films. The deposited films show high optical quality as confirmed by observation of both, sharp edge in the transmittance spectra and strong PL intensity at room temperature. Furthermore, we found a strong effect of the growth conditions on the optical band gap of the deposited films; where remarkable red-shift in the absorption edge with temperature is clearly seen in both transmission and PL spectra. Such tuning of both optical band gap of the deposited CdS films can be utilized for tuning the electronic bands' alignments between CdS and other light-harvesting materials, like CuInGaSe or CdTe, for potential improvement in the efficiency of solar cells devices based on these heterostructures.

Keywords: chemical deposition, CdS, optical properties, surface, thin film

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935 Comparison of Extended Kalman Filter and Unscented Kalman Filter for Autonomous Orbit Determination of Lagrangian Navigation Constellation

Authors: Youtao Gao, Bingyu Jin, Tanran Zhao, Bo Xu

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The history of satellite navigation can be dated back to the 1960s. From the U.S. Transit system and the Russian Tsikada system to the modern Global Positioning System (GPS) and the Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS), performance of satellite navigation has been greatly improved. Nowadays, the navigation accuracy and coverage of these existing systems have already fully fulfilled the requirement of near-Earth users, but these systems are still beyond the reach of deep space targets. Due to the renewed interest in space exploration, a novel high-precision satellite navigation system is becoming even more important. The increasing demand for such a deep space navigation system has contributed to the emergence of a variety of new constellation architectures, such as the Lunar Global Positioning System. Apart from a Walker constellation which is similar to the one adopted by GPS on Earth, a novel constellation architecture which consists of libration point satellites in the Earth-Moon system is also available to construct the lunar navigation system, which can be called accordingly, the libration point satellite navigation system. The concept of using Earth-Moon libration point satellites for lunar navigation was first proposed by Farquhar and then followed by many other researchers. Moreover, due to the special characteristics of Libration point orbits, an autonomous orbit determination technique, which is called ‘Liaison navigation’, can be adopted by the libration point satellites. Using only scalar satellite-to-satellite tracking data, both the orbits of the user and libration point satellites can be determined autonomously. In this way, the extensive Earth-based tracking measurement can be eliminated, and an autonomous satellite navigation system can be developed for future space exploration missions. The method of state estimate is an unnegligible factor which impacts on the orbit determination accuracy besides type of orbit, initial state accuracy and measurement accuracy. We apply the extended Kalman filter(EKF) and the unscented Kalman filter(UKF) to determinate the orbits of Lagrangian navigation satellites. The autonomous orbit determination errors are compared. The simulation results illustrate that UKF can improve the accuracy and z-axis convergence to some extent.

Keywords: extended Kalman filter, autonomous orbit determination, unscented Kalman filter, navigation constellation

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934 Designing the Lesson Instructional Plans for Exploring the STEM Education and Creative Learning Processes to Students' Logical Thinking Abilities with Different Learning Outcomes in Chemistry Classes

Authors: Pajaree Naramitpanich, Natchanok Jansawang, Panwilai Chomchid

Abstract:

The aims of this are compared between the students’ logical thinking abilities of their learning for designing the 5-lesson instructional plans of the 2-instructional methods, namely; the STEM Education and the Creative Learning Process (CLP) for developing students’ logical thinking abilities that a sample consisted of 90 students from two chemistry classes of different learning outcomes in Wapi Phathum School with the cluster random sampling technique was used at the 11th grade level. To administer of their learning environments with the 45-experimenl student group by the STEM Education method and the 45-controlling student group by the Creative Learning Process. These learning different groups were obtained using the 5 instruments; the 5-lesson instructional plans of the STEM Education and the Creative Learning Process to enhance the logical thinking tests on Mineral issue were used. The efficiency of the Creative Learning Processes (CLP) Model and the STEM Education’s innovations of these each five instructional lesson plans based on criteria are higher than of 80/80 standard level with the IOC index from the expert educators. The averages mean scores of students’ learning achievement motives were assessed with the Pre and Post Techniques and Logical Thinking Ability Test (LTAT) and dependent t-test analysis were differentiated between the CLP and the STEM, significantly. Students’ perceptions of their chemistry classroom environment inventories with the MCI with the CLP and the STEM methods also were found, differently. Associations between students’ perceptions of their chemistry classroom learning environment inventories on the CLP Model and the STEM Education learning designs toward their logical thinking abilities toward chemistry, the predictive efficiency of R2 values indicate that 68% and 76% of the variances in students’ logical thinking abilities toward chemistry to their controlling and experimental chemistry classroom learning environmental groups with the MCI were correlated at .05 levels, significantly. Implementations of this result are showed the students’ learning by the CLP of the potential thinking life-changing roles in most their logical thinking abilities that it is revealed that the students perceive their abilities to be highly learning achievement in chemistry group are differentiated with the STEM education of students’ outcomes.

Keywords: design, the lesson instructional plans, the stem education, the creative learning process, logical thinking ability, different, learning outcome, student, chemistry class

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933 Experimental and Numerical Investigation of Micro-Welding Process and Applications in Digital Manufacturing

Authors: Khaled Al-Badani, Andrew Norbury, Essam Elmshawet, Glynn Rotwell, Ian Jenkinson , James Ren

Abstract:

Micro welding procedures are widely used for joining materials, developing duplex components or functional surfaces, through various methods such as Micro Discharge Welding or Spot Welding process, which can be found in the engineering, aerospace, automotive, biochemical, biomedical and numerous other industries. The relationship between the material properties, structure and processing is very important to improve the structural integrity and the final performance of the welded joints. This includes controlling the shape and the size of the welding nugget, state of the heat affected zone, residual stress, etc. Nowadays, modern high volume productions require the welding of much versatile shapes/sizes and material systems that are suitable for various applications. Hence, an improved understanding of the micro welding process and the digital tools, which are based on computational numerical modelling linking key welding parameters, dimensional attributes and functional performance of the weldment, would directly benefit the industry in developing products that meet current and future market demands. This paper will introduce recent work on developing an integrated experimental and numerical modelling code for micro welding techniques. This includes similar and dissimilar materials for both ferrous and non-ferrous metals, at different scales. The paper will also produce a comparative study, concerning the differences between the micro discharge welding process and the spot welding technique, in regards to the size effect of the welding zone and the changes in the material structure. Numerical modelling method for the micro welding processes and its effects on the material properties, during melting and cooling progression at different scales, will also be presented. Finally, the applications of the integrated numerical modelling and the material development for the digital manufacturing of welding, is discussed with references to typical application cases such as sensors (thermocouples), energy (heat exchanger) and automotive structures (duplex steel structures).

Keywords: computer modelling, droplet formation, material distortion, materials forming, welding

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932 Enhancing Skills of Mothers of Asthmatic Children in Techniques of Drug Administration

Authors: Erna Judith Roach, Nalini Bhaskaranand

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Background & Significance: Asthma is the most common chronic disease among children. Education is the cornerstone of management of asthma to help the affected children. In India there are about 1.5- 3.0 million asthmatic children in the age group of 5-11 years. Many parents face management dilemmas in administration of medications to their children. Mothers being primary caregivers of children are often responsible for administering medications to them. The purpose of the study was to develop an educational package on techniques of drug administration for mothers of asthmatic children and determine its effectiveness in terms of improvement in skill in drug administration. Methodology: A quasi- experimental time series pre-test post -test control group design was used. Mothers of asthmatic children attending paediatric outpatient departments of selected hospitals along with their children between 5 and 12 years were included. Sample size consisted of 40 mothers in the experimental and 40 mothers in the control groups. Block randomization was used to assign samples to both the groups. The data collection instruments used were Baseline Proforma, Clinical Proforma, Daily asthma drug intake and symptoms diary and Observation Rating Scales on technique of using a metered dose inhaler with spacer; metered dose inhaler with facemask; metered dose inhaler alone and dry powder inhaler. The educational package consisted of a video and booklet on techniques of drug administration. Data were collected at baseline, 1, 3 and 6 months. Findings: The mean post-test scores in techniques of drug administration were higher than the mean pre-test scores in the experimental group in all techniques. The Friedman test (p < 0.01), Wilcoxon Signed Rank test (p < 0.008) and Mann Whitney U (p < 0.01) showed statistically significant difference in the experimental group than the control group. There was significant decrease in the average number of symptom days (11 Vs. 4 days/ month) and hospital visits (5 to 1 per month) in the experimental group when compared to the control group. Conclusion: The educational package was found to be effective in improving the skill of mothers in drug administration in all the techniques, especially with using the metered dose inhaler with spacer.

Keywords: childhood asthma, drug administration, mothers of children, inhaler

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931 Potential Contribution of Local Food Resources towards Sustainable Food Tourism in Nueva Vizcaya

Authors: Marvin Eslava

Abstract:

The over-arching aim of this research is to determine the potential contribution of local food resources to the tourism growth of Nueva Vizcaya. It reviews some of the underpinning concepts and to provide a set of considerations for stakeholders to maximize the opportunity of local food can offer to businesses and the wider community. The basis of the study is to develop a sustainable food tourism model for Nueva Vizcaya. For the purpose of this research, there were 60 total numbers of respondents classified as samples from a six municipality. The respondents of the study were stakeholder consisting of government official, local producers, businessman and Non-government organizations in the selected municipalities of Nueva Vizcaya. Stratified purposive sampling was the appropriate technique that was used to the local government officials and employees, NGOs including the businessmen who are associated with local food resources and local producers. The documentary study, focus group discussion and survey questionnaire was used in order to meet the objectives of the study. Kruskall Wallis test was used to test the variances the ratings of the participants. This was used in the computation of hypothesis. The study concluded that the province of Nueva Vizcaya is blessed for its rich farmlands and fertile mountain soil boasts to produce high quality agricultural products. It is a home of various different indigenous groups creating a wide range of local cuisine. The province has substantial local food development evidence by the various food tourism related resources, increase in facilities and celebrating food tourism related events. The local food resources provide extensive potential economic empowerment and help in building the identity of the province. In addition, the local food resources extensively enhance the agriculture sector and other attractions in the province. Finally, it helps to preserve the authenticity of the food culture and generated pride among all stakeholders extensively. All stakeholders have the same perception on the potential contribution of local food resources to the development of the province of Nueva Vizcaya. The public and private sectors are cognizant on their roles to support the production of local food resources in Nueva Vizcaya. Major challenges and barriers in the development of sustainable food tourism in Nueva Vizcaya include production or supply and marketing.

Keywords: local food resources, contribution, food tourism, benefits

Procedia PDF Downloads 261
930 Gadolinium-Based Polymer Nanostructures as Magnetic Resonance Imaging Contrast Agents

Authors: Franca De Sarno, Alfonso Maria Ponsiglione, Enza Torino

Abstract:

Recent advances in diagnostic imaging technology have significantly contributed to a better understanding of specific changes associated with diseases progression. Among different imaging modalities, Magnetic Resonance Imaging (MRI) represents a noninvasive medical diagnostic technique, which shows low sensitivity and long acquisition time and it can discriminate between healthy and diseased tissues by providing 3D data. In order to improve the enhancement of MRI signals, some imaging exams require intravenous administration of contrast agents (CAs). Recently, emerging research reports a progressive deposition of these drugs, in particular, gadolinium-based contrast agents (GBCAs), in the body many years after multiple MRI scans. These discoveries confirm the need to have a biocompatible system able to boost a clinical relevant Gd-chelate. To this aim, several approaches based on engineered nanostructures have been proposed to overcome the common limitations of conventional CAs, such as the insufficient signal-to-noise ratios due to relaxivity and poor safety profile. In particular, nanocarriers, labeling or loading with CAs, capable of carrying high payloads of CAs have been developed. Currently, there’s no a comprehensive understanding of the thermodynamic contributions enable of boosting the efficacy of conventional CAs by using biopolymers matrix. Thus, considering the importance of MRI in diagnosing diseases, here it is reported a successful example of the next generation of these drugs where the commercial gadolinium chelate is incorporate into a biopolymer nanostructure, formed by cross-linked hyaluronic acid (HA), with improved relaxation properties. In addition, they are highlighted the basic principles ruling biopolymer-CA interactions in the perspective of their influence on the relaxometric properties of the CA by adopting a multidisciplinary experimental approach. On the basis of these discoveries, it is clear that the main point consists in increasing the rigidification of readily-available Gd-CAs within the biopolymer matrix by controlling the water dynamics, the physicochemical interactions, and the polymer conformations. In the end, the acquired knowledge about polymer-CA systems has been applied to develop of Gd-based HA nanoparticles with enhanced relaxometric properties.

Keywords: biopolymers, MRI, nanoparticles, contrast agent

Procedia PDF Downloads 149
929 Suitable Site Selection of Small Dams Using Geo-Spatial Technique: A Case Study of Dadu Tehsil, Sindh

Authors: Zahid Khalil, Saad Ul Haque, Asif Khan

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Decision making about identifying suitable sites for any project by considering different parameters is difficult. Using GIS and Multi-Criteria Analysis (MCA) can make it easy for those projects. This technology has proved to be an efficient and adequate in acquiring the desired information. In this study, GIS and MCA were employed to identify the suitable sites for small dams in Dadu Tehsil, Sindh. The GIS software is used to create all the spatial parameters for the analysis. The parameters that derived are slope, drainage density, rainfall, land use / land cover, soil groups, Curve Number (CN) and runoff index with a spatial resolution of 30m. The data used for deriving above layers include 30-meter resolution SRTM DEM, Landsat 8 imagery, and rainfall from National Centre of Environment Prediction (NCEP) and soil data from World Harmonized Soil Data (WHSD). Land use/Land cover map is derived from Landsat 8 using supervised classification. Slope, drainage network and watershed are delineated by terrain processing of DEM. The Soil Conservation Services (SCS) method is implemented to estimate the surface runoff from the rainfall. Prior to this, SCS-CN grid is developed by integrating the soil and land use/land cover raster. These layers with some technical and ecological constraints are assigned weights on the basis of suitability criteria. The pairwise comparison method, also known as Analytical Hierarchy Process (AHP) is taken into account as MCA for assigning weights on each decision element. All the parameters and group of parameters are integrated using weighted overlay in GIS environment to produce suitable sites for the Dams. The resultant layer is then classified into four classes namely, best suitable, suitable, moderate and less suitable. This study reveals a contribution to decision-making about suitable sites analysis for small dams using geospatial data with minimal amount of ground data. This suitability maps can be helpful for water resource management organizations in determination of feasible rainwater harvesting structures (RWH).

Keywords: Remote sensing, GIS, AHP, RWH

Procedia PDF Downloads 389
928 Economic Analysis of Post-Harvest Losses in Plantain (and Banana): A Case Study of South Western Nigeria

Authors: O. R. Adeniyi, A. Ayandiji

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Losses are common in most vegetables because the fruit ripens rapidly and most plantain products can only be stored for a few days thereby limiting their utilization. Plantain (and banana) is highly perishable at the ambient temperature prevalent in the tropics. The specific objective of this study is to identify the socioeconomic characteristics of banana/plantain dealers and determine the perceived effect of the losses incurred in the process of marketing banana/plantain. The study was carried out in Ondo and Lagos states of south-western Nigeria. Purposive sampling technique was used to collect information from “Kolawole plantain depot”, the point of purchase in Ondo State and “Alamutu plantain market” in Mushin the point of sales in Lagos state. Preliminary study was conducted with the use of primary data collected through well-structured questionnaires administered on 60 respondents and 55 fully completed ones analysed. Budgeting, gross margin and multiple linear regression were used for analyses. Most merchants were found to be in the middle age class (30-50 years), majority of whom were female and completed their secondary school education, with eighty percent having more than 5 years’ experience of in banana/plantain marketing. The highest losses were incurred during transportation and these losses constitute about 5.62 percent of the potential total revenue. On the average, loss in gross margin is about ₦6,000.00 per merchant. The impacts of these losses are reflected in the continuously reducing level of their income. Age of the respondents played a major role in determining the level of care in the handling of the fruits. The middle age class tends to be more favoured. In conclusion, the merchants need adequate and sustainable transportation and storage facilities as a matter of utmost urgency. There is the need for government to encourage producers of the product (farmers) by giving them motivating incentives and ensuring that the environment is made conducive also for dealers by providing adequate storage facilities and ready markets locally and possibly for export.

Keywords: post-harvest, losses, plantain, banana, simple regression

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927 Neuroevolution Based on Adaptive Ensembles of Biologically Inspired Optimization Algorithms Applied for Modeling a Chemical Engineering Process

Authors: Sabina-Adriana Floria, Marius Gavrilescu, Florin Leon, Silvia Curteanu, Costel Anton

Abstract:

Neuroevolution is a subfield of artificial intelligence used to solve various problems in different application areas. Specifically, neuroevolution is a technique that applies biologically inspired methods to generate neural network architectures and optimize their parameters automatically. In this paper, we use different biologically inspired optimization algorithms in an ensemble strategy with the aim of training multilayer perceptron neural networks, resulting in regression models used to simulate the industrial chemical process of obtaining bricks from silicone-based materials. Installations in the raw ceramics industry, i.e., bricks, are characterized by significant energy consumption and large quantities of emissions. In addition, the initial conditions that were taken into account during the design and commissioning of the installation can change over time, which leads to the need to add new mixes to adjust the operating conditions for the desired purpose, e.g., material properties and energy saving. The present approach follows the study by simulation of a process of obtaining bricks from silicone-based materials, i.e., the modeling and optimization of the process. Optimization aims to determine the working conditions that minimize the emissions represented by nitrogen monoxide. We first use a search procedure to find the best values for the parameters of various biologically inspired optimization algorithms. Then, we propose an adaptive ensemble strategy that uses only a subset of the best algorithms identified in the search stage. The adaptive ensemble strategy combines the results of selected algorithms and automatically assigns more processing capacity to the more efficient algorithms. Their efficiency may also vary at different stages of the optimization process. In a given ensemble iteration, the most efficient algorithms aim to maintain good convergence, while the less efficient algorithms can improve population diversity. The proposed adaptive ensemble strategy outperforms the individual optimizers and the non-adaptive ensemble strategy in convergence speed, and the obtained results provide lower error values.

Keywords: optimization, biologically inspired algorithm, neuroevolution, ensembles, bricks, emission minimization

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926 Compensation of Bulk Charge Carriers in Bismuth Based Topological Insulators via Swift Heavy Ion Irradiation

Authors: Jyoti Yadav, Rini Singh, Anoop M.D, Nisha Yadav, N. Srinivasa Rao, Fouran Singh, Takayuki Ichikawa, Ankur Jain, Kamlendra Awasthi, Manoj Kumar

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Nanocrystalline films exhibit defects and strain induced by its grain boundaries. Defects and strain affect the physical as well as topological insulating properties of the Bi2Te3 thin films by changing their electronic structure. In the present studies, the effect of Ni7+ ion irradiation on the physical and electrical properties of Bi2Te3 thin films was studied. The films were irradiated at five different fluences (5x1011, 1x1012, 3x1012, 5x1012, 1x1013 ions/cm2). Thin films synthesized using the e-beam technique possess a rhombohedral crystal structure with the R-3m space group. The average crystallite size, as determined by x-ray diffraction (XRD) peak broadening, was found to be 18.5 ± 5 (nm). It was also observed that irradiation increases the induced strain. Raman Spectra of the films demonstrate the splitting of A_1u^1 modes originating from the vibrations along the c-axis. This is by the variation in the lattice parameter ‘c,’ as observed through XRD. The atomic force microscopy study indicates the decrease in surface roughness up to the fluence of 3x1012 ions/cm2 and further increasing the fluence increases the roughness. The decrease in roughness may be due to the growth of smaller nano-crystallites on the surface of thin films due to irradiation-induced annealing. X-ray photoelectron spectroscopy studies reveal the composition to be in close agreement to the nominal values i.e. Bi2Te3. The resistivity v/s temperature measurements revealed an increase in resistivity up to the fluence 3x1012 ions/cm2 and a decrease on further increasing the fluence. The variation in electrical resistivity is corroborated with the change in the carrier concentration as studied through low-temperature Hall measurements. A crossover from the n-type to p-type carriers was achieved in the irradiated films. Interestingly, tuning of the Fermi level by compensating the bulk carriers using ion-irradiation could be achieved.

Keywords: Annealing, Irradiation, Fermi level, Tuning

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925 Development and Validation of a Coronary Heart Disease Risk Score in Indian Type 2 Diabetes Mellitus Patients

Authors: Faiz N. K. Yusufi, Aquil Ahmed, Jamal Ahmad

Abstract:

Diabetes in India is growing at an alarming rate and the complications caused by it need to be controlled. Coronary heart disease (CHD) is one of the complications that will be discussed for prediction in this study. India has the second most number of diabetes patients in the world. To the best of our knowledge, there is no CHD risk score for Indian type 2 diabetes patients. Any form of CHD has been taken as the event of interest. A sample of 750 was determined and randomly collected from the Rajiv Gandhi Centre for Diabetes and Endocrinology, J.N.M.C., A.M.U., Aligarh, India. Collected variables include patients data such as sex, age, height, weight, body mass index (BMI), blood sugar fasting (BSF), post prandial sugar (PP), glycosylated haemoglobin (HbA1c), diastolic blood pressure (DBP), systolic blood pressure (SBP), smoking, alcohol habits, total cholesterol (TC), triglycerides (TG), high density lipoprotein (HDL), low density lipoprotein (LDL), very low density lipoprotein (VLDL), physical activity, duration of diabetes, diet control, history of antihypertensive drug treatment, family history of diabetes, waist circumference, hip circumference, medications, central obesity and history of CHD. Predictive risk scores of CHD events are designed by cox proportional hazard regression. Model calibration and discrimination is assessed from Hosmer Lemeshow and area under receiver operating characteristic (ROC) curve. Overfitting and underfitting of the model is checked by applying regularization techniques and best method is selected between ridge, lasso and elastic net regression. Youden’s index is used to choose the optimal cut off point from the scores. Five year probability of CHD is predicted by both survival function and Markov chain two state model and the better technique is concluded. The risk scores for CHD developed can be calculated by doctors and patients for self-control of diabetes. Furthermore, the five-year probabilities can be implemented as well to forecast and maintain the condition of patients.

Keywords: coronary heart disease, cox proportional hazard regression, ROC curve, type 2 diabetes Mellitus

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924 Pre-service Social Studies Teachers Readiness in Promoting 21st Century Learning: Evidence from a Ghanaian University

Authors: Joseph Bentil

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Successful acquisition of 21st-century competencies needed by students to navigate through the ever-changing world requires that they are taught and molded by 21st-century teachers with the needed professional competencies. Accordingly, this study sought to understand the readiness and how efficacious pre-service Social Studies specialism students are towards the implementation of the Common Core Social Studies Curriculum in the Junior High Schools in Ghana. Theory of Experience served as the theoretical lens for the study. Working within the pragmatist paradigm, this study utilized the cross-sectional descriptive survey design with a mixed method approach where, through census sampling technique, all the 120 pre-service Social Studies specialism students were sampled for the study. A structured questionnaire and an interview guide were the instruments employed for data collection. Descriptive statistics (mean, standard deviation and inferential statistics like independent samples t-test, one-way between groups ANOVA and Pearson Product Moment Correlation) were employed in the analysis the research questions and hypotheses with the aid of version 28 of SPSS while the qualitative data was analyzed using thematic analysis. The findings discovered that pre-service Social Studies teachers were highly ready and efficacious towards implementing the Common Core Junior High School Social Studies curriculum. However, male pre-service teachers were highly efficacious and ready than their female counterparts. Besides, it was disclosed that pre-service teachers within the 31-40 years age bracket were found to be highly efficacious and ready than their colleagues with 20-30 and below 20 years age bracket respectively. The findings further revealed that there was a moderate and statistically significant positive relationship between pre-service teachers’ readiness and efficacy in implementing the Common Core Social Studies curriculum. Therefore, the study recommended that interventional programmes aimed at raising the readiness and efficacy beliefs of pre-service teachers should be targeted towards female preservice teachers and those below 20 years age bracket for successful implementation and realization of the competencies enshrined in the common core social Studies curriculum.

Keywords: pre-service, readiness, social studies, teachers

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923 Comparison of Propofol versus Ketamine-Propofol Combination as an Anesthetic Agent in Supratentorial Tumors: A Randomized Controlled Study

Authors: Jakkireddy Sravani

Abstract:

Introduction: The maintenance of hemodynamic stability is of pivotal importance in supratentorial surgeries. Anesthesia for supratentorial tumors requires an understanding of localized or generalized rising ICP, regulation, and maintenance of intracerebral perfusion, and avoidance of secondary systemic ischemic insults. We aimed to compare the effects of the combination of ketamine and propofol with propofol alone when used as an induction and maintenance anesthetic agent during supratentorial tumors. Methodology: This prospective, randomized, double-blinded controlled study was conducted at AIIMS Raipur after obtaining the institute Ethics Committee approval (1212/IEC-AIIMSRPR/2022 dated 15/10/2022), CTRI/2023/01/049298 registration and written informed consent. Fifty-two supratentorial tumor patients posted for craniotomy and excision were included in the study. The patients were randomized into two groups. One group received a combination of ketamine and propofol, and the other group received propofol for induction and maintenance of anesthesia. Intraoperative hemodynamic stability and quality of brain relaxation were studied in both groups. Statistical analysis and technique: An MS Excel spreadsheet program was used to code and record the data. Data analysis was done using IBM Corp SPSS v23. The independent sample "t" test was applied for continuously dispersed data when two groups were compared, the chi-square test for categorical data, and the Wilcoxon test for not normally distributed data. Results: The patients were comparable in terms of demographic profile, duration of the surgery, and intraoperative input-output status. The trends in BIS over time were similar between the two groups (p-value = 1.00). Intraoperative hemodynamics (SBP, DBP, MAP) were better maintained in the ketamine and propofol combination group during induction and maintenance (p-value < 0.01). The quality of brain relaxation was comparable between the two groups (p-value = 0.364). Conclusion: Ketamine and propofol combination for the induction and maintenance of anesthesia was associated with superior hemodynamic stability, required fewer vasopressors during excision of supratentorial tumors, provided adequate brain relaxation, and some degree of neuroprotection compared to propofol alone.

Keywords: supratentorial tumors, hemodynamic stability, brain relaxation, ketamine, propofol

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922 Modelling Tyre Rubber Materials for High Frequency FE Analysis

Authors: Bharath Anantharamaiah, Tomas Bouda, Elke Deckers, Stijn Jonckheere, Wim Desmet, Juan J. Garcia

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Automotive tyres are gaining importance recently in terms of their noise emission, not only with respect to reduction in noise, but also their perception and detection. Tyres exhibit a mechanical noise generation mechanism up to 1 kHz. However, owing to the fact that tyre is a composite of several materials, it has been difficult to model it using finite elements to predict noise at high frequencies. The currently available FE models have a reliability of about 500 Hz, the limit which, however, is not enough to perceive the roughness or sharpness of noise from tyre. These noise components are important in order to alert pedestrians on the street about passing by slow, especially electric vehicles. In order to model tyre noise behaviour up to 1 kHz, its dynamic behaviour must be accurately developed up to a 1 kHz limit using finite elements. Materials play a vital role in modelling the dynamic tyre behaviour precisely. Since tyre is a composition of several components, their precise definition in finite element simulations is necessary. However, during the tyre manufacturing process, these components are subjected to various pressures and temperatures, due to which these properties could change. Hence, material definitions are better described based on the tyre responses. In this work, the hyperelasticity of tyre component rubbers is calibrated, using the design of experiments technique from the tyre characteristic responses that are measured on a stiffness measurement machine. The viscoelasticity of rubbers are defined by the Prony series for rubbers, which are determined from the loss factor relationship between the loss and storage moduli, assuming that the rubbers are excited within the linear viscoelasticity ranges. These values of loss factor are measured and theoretically expressed as a function of rubber shore hardness or hyperelasticities. From the results of the work, there exists a good correlation between test and simulation vibrational transfer function up to 1 kHz. The model also allows flexibility, i.e., the frequency limit can also be extended, if required, by calibrating the Prony parameters of rubbers corresponding to the frequency of interest. As future work, these tyre models are used for noise generation at high frequencies and thus for tyre noise perception.

Keywords: tyre dynamics, rubber materials, prony series, hyperelasticity

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921 The Effect of Leadership Styles on Employees’ Organizational Commitment at Ambo Woreda Public Organizations, Oromia Regional State, Ethiopia

Authors: Mengistu Tulu Balcha, Endale Gadisa Motuma

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The purpose of this study was to assess the effect of leadership styles on employees’ organizational commitments in Ambo Woreda public organizations. The study was guided by a Descriptive survey and correlation research design of the quantitative method. By using simple random sampling techniques, 80 participants of employees and by purposive sampling technique, 32 leaders were involved in research from five purposely selected Woreda public organizations without a non-response rate. Two separate instruments adopted from previous studies, namely the multifactor leadership questionnaire (MLQ), which has 36 items and the Organizational Commitment Questionnaire (OCQ), which has 12 items, were used as a data instrument tool. These items were rated by using a five-point Likert-scale. The survey data was processed by using an SPSS (version 27). Descriptive statistics to calculate mean and standard deviations of leaders’ and employees’ responses to leadership styles dominantly practiced in order to determine their perceptions, MLQ of leaders’ and employees’ responses (independent sample), and multiple linear regressions were used to calculate the effect of leadership styles on organizational commitment. The findings of the study show that the leadership style dominantly practiced in Ambo Woreda public organizations was more transactional than transformational and followed by laissez-faire. The level of EOC was ranked as continuance commitment and had the highest mean score, followed by normative commitment and then affective commitment. There is a strong, positive and significant relationship between leadership style dimensions and employees’ organizational commitment. Leadership styles were found statistically significant to predict employee commitment and there was a significant linear relationship between independent variables and dependent variables. Out of the three leadership variables, the transactional leadership style has the highest contribution, followed by the transformational leadership style, whereas the laissez-faire leadership style has the least contribution in predicting employees’ organizational commitment. Finally, the researcher forwarded possible recommendations for Ambo Woreda public organizational leaders and employees to work on improving leadership styles and employees’ commitment collaboratively.

Keywords: organizations, employee, relations, commitments, style

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920 Suitability of Wood Sawdust Waste Reinforced Polymer Composite for Fireproof Doors

Authors: Timine Suoware, Sylvester Edelugo, Charles Amgbari

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The susceptibility of natural fibre polymer composites to flame has necessitated research to improve and develop flame retardant (FR) to delay the escape of combustible volatiles. Previous approaches relied mostly on FR such as aluminium tri-hydroxide (ATH) and ammonium polyphosphate (APP) to improve fire performances of wood sawdust polymer composites (WSPC) with emphasis on non-structural building applications. In this paper, APP was modified with gum Arabic powder (GAP) and then hybridized with ATH at 0, 12 and 18% loading ratio to form new FR species; WSPC12%APP-GAP and WSPC18%ATH/APP-GAP. The FR species were incorporated in wood sawdust waste reinforced in polyester resin to form panels for fireproof doors. The panels were produced using hand lay compression moulding technique and cured at room temperature. Specimen cut from panels were then tested for tensile strength (TS), flexural strength (FS) and impact strength (IS) using universal testing machine and impact tester; thermal stability using (TGA/DSC 1: Metler Toledo); time-to-ignition (Tig), heat release rates (HRR); peak HRR (HRRp), average HRR (HRRavg), total HRR (THR), peak mass loss rate (MLRp), average smoke production rate (SPRavg) and carbon monoxide production (COP ) were obtained using the cone calorimeter apparatus. From the mechanical properties obtained, improvements of IS for the panels were not noticeable whereas TS and FS for WSPC12%APP-GAP respectively stood at 12.44 MPa and 85.58 MPa more than those without FR (WSPC0%). For WSC18%ATH/APP-GAP TS and FS respectively stood at 16.45 MPa and 50.49 MPa more compared to (WSPC0%). From the thermal analysis, the panels did not exhibit any significant change as early degradation was observed. At 900 OC, the char residues improved by 15% for WSPC12%APP-GAP and 19% for WSPC18%ATH/APP-GAP more than (WSC0%) at 5%, confirming the APP-GAP to be a good FR. At 50 kW/m2 heat flux (HF), WSPC12%APP-GAP improved better the fire behaviour of the panels when compared to WSC0% as follows; Tig = 46 s, HRRp = 56.1 kW/2, HRRavg = 32.8 kW/m2, THR = 66.6 MJ/m2, MLRp = 0.103 g/s, TSR = 0.04 m2/s and COP = 0.051 kg/kg. These were respectively more than WSC0%. It can be concluded that the new concept of modifying FR with GAP in WSC could meet the requirement of a fireproof door for building applications.

Keywords: composite, flame retardant, wood sawdust, fireproof doors

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919 Exploring the Rhinoceros Beetles of a Tropical Forest of Eastern Himalayas

Authors: Subhankar Kumar Sarkar

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Beetles of the subfamily Dynastinae under the family Scarabaeidae of the insect order Coleoptera are popularly known as ‘Rhinoceros beetles’ because of the characteristic horn borne by the males on their head. These horns are dedicated in mating battle against other males and have evolved as a result of phenotypic plasticity. Scarabaeidae is the largest of all families under Coleoptera and is composed of 11 subfamilies, of which the subfamily Dynastinae is represented by approximately 300 species. Some of these beetles have been reported to cause considerable damage to agriculture and forestry both in their larval and adult stages, while many of them are beneficial as they pollinate plants and recycle plant materials. Eastern Himalayas is regarded as one of the 35 biodiversity hotspot zones of the world and one of the four of India, which is exhibited by its rich and megadiverse tropical forests. However, our knowledge on the faunal diversity of these forests is very limited, particularly for the insect fauna. One such tropical forest of Eastern Himalayas is the ‘Buxa Tiger Reserve’ located between latitudes 26°30” to 26°55” North and Longitudes 89°20” to 89˚35” East of India and occupies an area of about 759.26 square kilometers. It is with this background an attempt has been made to explore the insect fauna of the forest. Insect sampling was carried out in each beat and range of Buxa Tiger Reserve in all the three seasons viz, Premonsoon, Monsoon, and Postmonsoon. Sample collections were done by sweep nets, hand picking technique and pit fall traps. UV light trap was used to collect the nocturnal insects. Morphological examinations of the collected samples were carried out with Stereozoom Binocular Microscopes (Zeiss SV6 and SV11) and were identified up to species level with the aid of relevant literature. Survey of the insect fauna of the forest resulted in the recognition of 76 scarab species, of which 8 belong to the subfamily dealt herein. Each of the 8 species represents a separate genus. The forest is dominated by the members of Xylotrupes gideon (Linnaeus) as is represented by highest number of individuals. The recorded taxa show about 12% endemism and are of mainly oriental in distribution. Premonsoon is the most favorable season for their occurrence and activity followed by Monsoon and Postmonsoon.

Keywords: Dynastinae, Scarabaeidae, diversity, Buxa Tiger Reserve

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918 Beneficial Effect of Micropropagation Coupled with Mycorrhization on Enhancement of Growth Performance of Medicinal Plants

Authors: D. H. Tejavathi

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Medicinal plants are globally valuable sources of herbal products. Wild populations of many medicinal plants are facing threat of extinction because of their narrow distribution, endemicity, and degradation of specific habitats. Micropropagation is an established in vitro technique by which large number of clones can be obtained from a small bit of explants in a short span of time within a limited space. Mycorrhization can minimize the transient transplantation shock, experienced by the micropropagated plants when they are transferred from lab to land. AM fungal association improves the physiological status of the host plants through better uptake of water and nutrients, particularly phosphorus. Consequently, the growth performance and biosynthesis of active principles are significantly enhanced in AM fungal treated plants. Bacopa monnieri, Andrographis paniculata, Agave vera-curz, Drymaria cordata and Majorana hortensis, important medicinal plants used in various indigenous systems of medicines, are selected for the present study. They form the main constituents of many herbal formulations. Standard in vitro techniques were followed to obtain the micropropagated plants. Shoot tips and nodal segments were used as explants. Explants were cultured on Murashige and Skoog, and Phillips and Collins media supplemented with various combinations of growth regulators. Multiple shoots were obtained on a media containing both auxins and cytokinins at various concentrations and combinations. Multiple shoots were then transferred to rooting media containing auxins for root induction. Thus, obtained in vitro regenerated plants were subjected to brief acclimatization before transferring them to land. One-month-old in vitro plants were treated with AM fungi, and the symbiotic effect on the overall growth parameters was analyzed. It was found that micropropagation coupled with mycorrhization has significant effect on the enhancement of biomass and biosynthesis of active principles in these selected medicinal plants. In vitro techniques coupled with mycorrhization have opened a possibility of obtaining better clones in respect of enhancement of biomass and biosynthesis of active principles. Beneficial effects of AM fungal association with medicinal plants are discussed.

Keywords: cultivation, medicinal plants, micropropagation, mycorrhization

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917 Evaluation of the Self-Organizing Map and the Adaptive Neuro-Fuzzy Inference System Machine Learning Techniques for the Estimation of Crop Water Stress Index of Wheat under Varying Application of Irrigation Water Levels for Efficient Irrigation Scheduling

Authors: Aschalew C. Workneh, K. S. Hari Prasad, C. S. P. Ojha

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The crop water stress index (CWSI) is a cost-effective, non-destructive, and simple technique for tracking the start of crop water stress. This study investigated the feasibility of CWSI derived from canopy temperature to detect the water status of wheat crops. Artificial intelligence (AI) techniques have become increasingly popular in recent years for determining CWSI. In this study, the performance of two AI techniques, adaptive neuro-fuzzy inference system (ANFIS) and self-organizing maps (SOM), are compared while determining the CWSI of paddy crops. Field experiments were conducted for varying irrigation water applications during two seasons in 2022 and 2023 at the irrigation field laboratory at the Civil Engineering Department, Indian Institute of Technology Roorkee, India. The ANFIS and SOM-simulated CWSI values were compared with the experimentally calculated CWSI (EP-CWSI). Multiple regression analysis was used to determine the upper and lower CWSI baselines. The upper CWSI baseline was found to be a function of crop height and wind speed, while the lower CWSI baseline was a function of crop height, air vapor pressure deficit, and wind speed. The performance of ANFIS and SOM were compared based on mean absolute error (MAE), mean bias error (MBE), root mean squared error (RMSE), index of agreement (d), Nash-Sutcliffe efficiency (NSE), and coefficient of correlation (R²). Both models successfully estimated the CWSI of the paddy crop with higher correlation coefficients and lower statistical errors. However, the ANFIS (R²=0.81, NSE=0.73, d=0.94, RMSE=0.04, MAE= 0.00-1.76 and MBE=-2.13-1.32) outperformed the SOM model (R²=0.77, NSE=0.68, d=0.90, RMSE=0.05, MAE= 0.00-2.13 and MBE=-2.29-1.45). Overall, the results suggest that ANFIS is a reliable tool for accurately determining CWSI in wheat crops compared to SOM.

Keywords: adaptive neuro-fuzzy inference system, canopy temperature, crop water stress index, self-organizing map, wheat

Procedia PDF Downloads 55