Search results for: interrupted time series designs
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 20565

Search results for: interrupted time series designs

17865 Application of Laser Spectroscopy for Detection of Actinides and Lanthanides in Solutions

Authors: Igor Izosimov

Abstract:

This work is devoted to applications of the Time-resolved laser-induced luminescence (TRLIF) spectroscopy and time-resolved laser-induced chemiluminescence spectroscopy for detection of lanthanides and actinides. Results of the experiments on Eu, Sm, U, and Pu detection in solutions are presented. The limit of uranyl detection (LOD) in urine in our TRLIF experiments was up to 5 pg/ml. In blood plasma LOD was 0.1 ng/ml and after mineralization was up to 8pg/ml – 10pg/ml. In pure solution, the limit of detection of europium was 0.005ng/ml and samarium, 0.07ng/ml. After addition urine, the limit of detection of europium was 0.015 ng/ml and samarium, 0.2 ng/ml. Pu, Np, and some U compounds do not produce direct luminescence in solutions, but when excited by laser radiation, they can induce chemiluminescence of some chemiluminogen (luminol in our experiments). It is shown that multi-photon scheme of chemiluminescence excitation makes chemiluminescence not only a highly sensitive but also a highly selective tool for the detection of lanthanides/actinides in solutions.

Keywords: actinides/lanthanides detection, laser spectroscopy with time resolution, luminescence/chemiluminescence, solutions

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17864 The Boy Who Cried Wolf-North Korea Nuclear Test and Its Implication to the Regional Stability

Authors: Mark Wenyi Lai

Abstract:

The very lethal weapon of nuclear warhead had threatened the survival of the world for half of the 20th century. When most of the countries have already denounced and stopped the development, one country is eager to produce and use them. Since 2006, Pyongyang has launched six times of nuclear tests. The most recent one in September 2017 signaled North Korea’s military capability to project the mass destruction through ICBM (Intercontinental Ballistic Missile) over Seoul, Tokyo, Guam, Hawaii, Alaska or probably the West Coast of the United States with the explosive energy ten times of the atom bombing of Hiroshima in 1945. This research paper adopted time-series content analysis focusing on the related countries responses to North Korea’s tests in 2006, 2009, 2013, and 2016. The preliminary hypotheses are first, North Korea determined to protect the regime by having triad nuclear capability. Negotiations are mere means to this end. Second, South Korea is paralyzed by its ineffective domestic politics and unable to develop its independent strategy toward the North. Third, Japan was using the external threat to campaign for its rearmament plan and brought instability in foreign relations. Fourth, China found herself in the strange position of defending the loyal buffer state meanwhile witnessing the fourth and dangerous neighboring country gaining the card into nuclear club. Fifth, the United States had admitted that North Korea’s going nuclear is unstoppable. Therefore, to keep the regional stability in the East Asia, the US relied on the new balance of power formed by everyone versus Pyongyang. But, countries in East Asia actually have problems getting along with each other. Sixth, Russia distanced herself from the North Kore row but benefitted by advancing its strategic importance in the Far East. Tracing back the history of nuclear states, this research paper concluded that North Korea will head on becoming a more confident country. The regional stability will restore once related countries deal with the new fact and treat Pyongyang regime with a new strategy. The gradual opening and economic reform are on the way for the North Korea in the near future.

Keywords: nuclear test, North Korea, six party talk, US foreign policy

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17863 The Application of Variable Coefficient Jacobian elliptic Function Method to Differential-Difference Equations

Authors: Chao-Qing Dai

Abstract:

In modern nonlinear science and textile engineering, nonlinear differential-difference equations are often used to describe some nonlinear phenomena. In this paper, we extend the variable coefficient Jacobian elliptic function method, which was used to find new exact travelling wave solutions of nonlinear partial differential equations, to nonlinear differential-difference equations. As illustration, we derive two series of Jacobian elliptic function solutions of the discrete sine-Gordon equation.

Keywords: discrete sine-Gordon equation, variable coefficient Jacobian elliptic function method, exact solutions, equation

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17862 Assessing Traffic Calming Measures for Safe and Accessible Emergency Routes in Norrkoping City in Sweden

Authors: Ghazwan Al-Haji

Abstract:

Most accidents occur in urban areas, and the most related casualties are vulnerable road users (pedestrians and cyclists). The traffic calming measures (TCMs) are widely used and considered to be successful in reducing speed and traffic volume. However, TCMs create unwanted effects include: noise, emissions, energy consumption, vehicle delays and emergency response time (ERT). Different vertical and horizontal TCMs have been already applied nationally (Sweden) and internationally with different impacts. It is a big challenge among traffic engineers, planners, and policy-makers to choose and priorities the best TCMs to be implemented. This study will assess the existing guidelines for TCMs in relation to safety and ERT with focus on data from Norrkoping city in Sweden. The expected results will save lives, time, and money on particularly Swedish Roads. The study will also review newly technologies and how they can improve safety and reduce ERT.

Keywords: traffic calming measures, traffic safety, delay time, vulnerable road users

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17861 Pressure Relief in Prosthetic Sockets through Hole Implementation Using Different Materials

Authors: Gabi N. Nehme

Abstract:

Below-knee amputees commonly experience asymmetrical gait patterns. It is generally believed that ischemia is related to the formation of pressure sores due to uneven distribution of forces. Micro-vascular responses can reveal local malnutrition. Changes in local skin blood supply under various external loading conditions have been studied for a number of years. Radionuclide clearance, photo-plethysmography, trans-cutaneous oxygen tension along with other studies showed that the blood supply would be influenced by the epidermal forces, and the rate and the amount of blood supply would decrease with increased epidermal loads being shear forces or normal forces. Several cases of socket designs were investigated using Finite Element Model (FEM) and Design of Experiment (DOE) to increase flexibility and minimize the pressure at the limb/socket interface using ultra high molecular weight polyethylene (UHMWPE) and polyamide 6 (PA6) or Duraform. The pressure reliefs at designated areas where reducing thickness is involved are seen to be critical in determination of amputees’ comfort and are very important to clinical applications. Implementing a hole between the Patellar Tendon (PT) and Distal Tibia (DT) would decrease stiffness and increase prosthesis range of motion where flexibility is needed. In addition, displacement and prosthetic energy storage increased without compromising mechanical efficiency and prosthetic design integrity.

Keywords: patellar tendon, distal tibia, prosthetic socket relief areas, hole implementation

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17860 The Effects of Early Maternal Separation on Risky Choice in Rats

Authors: Osvaldo Collazo, Cristiano Valerio Dos Santos

Abstract:

Early maternal separation has been shown to bring about many negative effects on behavior in rats. In the present study, we evaluated the effects of early maternal separation on risky choice in rats. One group of male and female Wistar rats was exposed to an early maternal separation protocol while a control group was left undisturbed. Then both groups were exposed to a series of behavioral tests, including a test of risky choice, where one alternative offered a constant reward while the other offered a variable reward. There was a difference between groups when they chose between a variable and a constant reward delay, but no other difference was significant. These results suggest that early maternal separation may be related to a greater preference for shorter delays, which is characteristic of more impulsive choices.

Keywords: early maternal separation, impulsivity, risky choice, variability

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17859 Ground State Properties of Neutron Magic Isotones

Authors: G. Saxena, M. Kaushik

Abstract:

In the present investigation, we have employed RMF+BCS (relativistic mean-field plus BCS) approach to carry out a systematic study for the ground state properties of the entire chains of even-even neutron magic nuclei represented by isotones of traditional neutron magic numbers N = 8, 20, 40, 50, 82, and 126. The main body of the results of our calculations includes the binding energy, deformation, two proton separation energies, rms radii of the proton and neutron distributions as well as the proton and neutron density profiles etc. Several of these results have been given in the form of a series of graphs for a ready reference. In addition, the possible locations of the proton and neutron drip-lines as well as the (Z,N) values for the shell closures as suggested by the detailed analyzes of the single particle spectra, and the two proton and two-neutron separation energies for the different isotonic chains are also discussed in detail.

Keywords: relativistic mean field theory, neutron magic nuclei, shell closure, separation energy, deformation

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17858 Revisiting the Historical Narratives of the Old Churches in Albay, Bikol Region, Philippines

Authors: Ruby Ann L. Ayo

Abstract:

As cultural heritage reflects the historical origin of a certain group of people, it reveals their customs, traits, beliefs, practices and even values they hold on for years. One of the tangible examples of cultural heritage is the physical structures including the old churches. The study looked-into the existing historical narratives of the century Old Catholic churches in the Province of Albay, Bikol Region, Philippines: NuestraSeñora de Salvacion in Joroan, Tiwi, Albay; the Our Lady of the Gate in Daraga, Albay; the San Juan de Bautista in Tabaco City and the St. John the Baptist in Camalig, Albay. The historical narratives were analysed in terms of validity and reliability of the secondary documents with reference to the elements of history revealing consistency and adequacy of historical facts. The contents were examined using a modified Checklist of Historical Documents. The historical narratives were likewise submitted to the content expert for validation as regards historical authenticity and accuracy. The contents of the narratives were scrutinized according to the following codes: (1.1) the Patron Saints;(1.2) factors that paved to their constructions; (1.3) the people responsible for their constructions; (1.4) the misconceptions about their constructions; and (1.5) their contributions to Bikol heritage. Based on the codes, themes were identified as: (2.1) Marian Devotees and Christ-centered Patron Saints; (2.2) geographical, socio-political and cultural factors; (2.3) church and government officials; (2.4) misconceptions on the dates of constructions and original sites; and (2.5) popular pilgrim sites and well-admired architectural designs.

Keywords: historical narratives, old churches, cultural heritage, historical validity and reliability, elements of history

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17857 Pueblos Mágicos in Mexico: The Loss of Intangible Cultural Heritage and Cultural Tourism

Authors: Claudia Rodriguez-Espinosa, Erika Elizabeth Pérez Múzquiz

Abstract:

Since the creation of the “Pueblos Mágicos” program in 2001, a series of social and cultural events had directly affected the heritage conservation of the 121 registered localities until 2018, when the federal government terminated the program. Many studies have been carried out that seek to analyze from different perspectives and disciplines the consequences that these appointments have generated in the “Pueblos Mágicos.” Multidisciplinary groups such as the one headed by Carmen Valverde and Liliana López Levi, have brought together specialists from all over the Mexican Republic to create a set of diagnoses of most of these settlements, and although each one has unique specificities, there is a constant in most of them that has to do with the loss of cultural heritage and that is related to transculturality. There are several factors identified that have fostered a cultural loss, as a direct reflection of the economic crisis that prevails in Mexico. It is important to remember that the origin of this program had as its main objective to promote the growth and development of local economies since one of the conditions for entering the program is that they have less than 20,000 inhabitants. With this goal in mind, one of the first actions that many “Pueblos Mágicos” carried out was to improve or create an infrastructure to receive both national and foreign tourists since this was practically non-existent. Creating hotels, restaurants, cafes, training certified tour guides, among other actions, have led to one of the great problems they face: globalization. Although by itself it is not bad, its impact in many cases has been negative for heritage conservation. The entry into and contact with new cultures has led to the undervaluation of cultural traditions, their transformation and even their total loss. This work seeks to present specific cases of transformation and loss of cultural heritage, as well as to reflect on the problem and propose scenarios in which the negative effects can be reversed. For this text, 36 “Pueblos Mágicos” have been selected for study, based on those settlements that are cited in volumes I and IV (the first and last of the collection) of the series produced by the multidisciplinary group led by Carmen Valverde and Liliana López Levi (researchers from UNAM and UAM Xochimilco respectively) in the project supported by CONACyT entitled “Pueblos Mágicos. An interdisciplinary vision”, of which we are part. This sample is considered representative since it forms 30% of the total of 121 “Pueblos Mágicos” existing at that moment. With this information, the elements of its intangible heritage loss or transformation have been identified in every chapter based on the texts written by the participants of that project. Finally, this text shows an analysis of the effects that this federal program, as a public policy applied to 132 populations, has had on the conservation or transformation of the intangible cultural heritage of the “Pueblos Mágicos.” Transculturality, globalization, the creation of identities and the desire to increase the flow of tourists have impacted the changes that traditions (main intangible cultural heritage) have had in the 18 years that the federal program lasted.

Keywords: public policies, cultural tourism, heritage preservation, pueblos mágicos program

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17856 Process Driven Architecture For The ‘Lessons Learnt’ Knowledge Sharing Framework: The Case Of A ‘Lessons Learnt’ Framework For KOC

Authors: Rima Al-Awadhi, Abdul Jaleel Tharayil

Abstract:

On a regular basis, KOC engages into various types of Projects. However, due to very nature and complexity involved, each project experience generates a lot of ‘learnings’ that need to be factored into while drafting a new contract and thus avoid repeating the same mistakes. But, many a time these learnings are localized and remain as tacit leading to scope re-work, larger cycle time, schedule overrun, adjustment orders and claims. Also, these experiences are not readily available to new employees leading to steep learning curve and longer time to competency. This is to share our experience in designing and implementing a process driven architecture for the ‘lessons learnt’ knowledge sharing framework in KOC. It high-lights the ‘lessons learnt’ sharing process adopted, integration with the organizational processes, governance framework, the challenges faced and learning from our experience in implementing a ‘lessons learnt’ framework.

Keywords: lessons learnt, knowledge transfer, knowledge sharing, successful practices, Lessons Learnt Workshop, governance framework

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17855 Tracking the Effect of Ibutilide on Amplitude and Frequency of Fibrillatory Intracardiac Electrograms Using the Regression Analysis

Authors: H. Hajimolahoseini, J. Hashemi, D. Redfearn

Abstract:

Background: Catheter ablation is an effective therapy for symptomatic atrial fibrillation (AF). The intracardiac electrocardiogram (IEGM) collected during this procedure contains precious information that has not been explored to its full capacity. Novel processing techniques allow looking at these recordings from different perspectives which can lead to improved therapeutic approaches. In our previous study, we showed that variation in amplitude measured through Shannon Entropy could be used as an AF recurrence risk stratification factor in patients who received Ibutilide before the electrograms were recorded. The aim of this study is to further investigate the effect of Ibutilide on characteristics of the recorded signals from the left atrium (LA) of a patient with persistent AF before and after administration of the drug. Methods: The IEGMs collected from different intra-atrial sites of 12 patients were studied and compared before and after Ibutilide administration. First, the before and after Ibutilide IEGMs that were recorded within a Euclidian distance of 3 mm in LA were selected as pairs for comparison. For every selected pair of IEGMs, the Probability Distribution Function (PDF) of the amplitude in time domain and magnitude in frequency domain was estimated using the regression analysis. The PDF represents the relative likelihood of a variable falling within a specific range of values. Results: Our observations showed that in time domain, the PDF of amplitudes was fitted to a Gaussian distribution while in frequency domain, it was fitted to a Rayleigh distribution. Our observations also revealed that after Ibutilide administration, the IEGMs would have significantly narrower short-tailed PDFs both in time and frequency domains. Conclusion: This study shows that the PDFs of the IEGMs before and after administration of Ibutilide represents significantly different properties, both in time and frequency domains. Hence, by fitting the PDF of IEGMs in time domain to a Gaussian distribution or in frequency domain to a Rayleigh distribution, the effect of Ibutilide can easily be tracked using the statistics of their PDF (e.g., standard deviation) while this is difficult through the waveform of IEGMs itself.

Keywords: atrial fibrillation, catheter ablation, probability distribution function, time-frequency characteristics

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17854 Study on an Integrated Real-Time Sensor in Droplet-Based Microfluidics

Authors: Tien-Li Chang, Huang-Chi Huang, Zhao-Chi Chen, Wun-Yi Chen

Abstract:

The droplet-based microfluidic are used as micro-reactors for chemical and biological assays. Hence, the precise addition of reagents into the droplets is essential for this function in the scope of lab-on-a-chip applications. To obtain the characteristics (size, velocity, pressure, and frequency of production) of droplets, this study describes an integrated on-chip method of real-time signal detection. By controlling and manipulating the fluids, the flow behavior can be obtained in the droplet-based microfluidics. The detection method is used a type of infrared sensor. Through the varieties of droplets in the microfluidic devices, the real-time conditions of velocity and pressure are gained from the sensors. Here the microfluidic devices are fabricated by polydimethylsiloxane (PDMS). To measure the droplets, the signal acquisition of sensor and LabVIEW program control must be established in the microchannel devices. The devices can generate the different size droplets where the flow rate of oil phase is fixed 30 μl/hr and the flow rates of water phase range are from 20 μl/hr to 80 μl/hr. The experimental results demonstrate that the sensors are able to measure the time difference of droplets under the different velocity at the voltage from 0 V to 2 V. Consequently, the droplets are measured the fastest speed of 1.6 mm/s and related flow behaviors that can be helpful to develop and integrate the practical microfluidic applications.

Keywords: microfluidic, droplets, sensors, single detection

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17853 Study on the Influence of Cladding and Finishing Materials of Apartment Buildings on the Architectural Identity of Amman

Authors: Asil Zureigat, Ayat Odat

Abstract:

Analyzing the old and bringing in the new is an ever ongoing process in driving innovations in architecture. This paper looks at the excessive use of stone in apartment buildings in Amman and speculates on the existing possibilities of changing the cladding material. By looking at architectural exceptions present in Amman the paper seeks to make the exception, the rule by adding new materials to the architectural library of Amman and in turn, project a series of possible new identities to the existing stone scape. Through distributing a survey, conducting a photographic study on exceptional buildings and shedding light on the historical narrative of stone, the paper highlights the ways in which new finishing materials such as plaster, paint and stone variations could be introduced in an attempt to project a new architectural identity to Amman.

Keywords: architectural city identity, cladding materials, façade architecture, image of the city

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17852 Data Quality Enhancement with String Length Distribution

Authors: Qi Xiu, Hiromu Hota, Yohsuke Ishii, Takuya Oda

Abstract:

Recently, collectable manufacturing data are rapidly increasing. On the other hand, mega recall is getting serious as a social problem. Under such circumstances, there are increasing needs for preventing mega recalls by defect analysis such as root cause analysis and abnormal detection utilizing manufacturing data. However, the time to classify strings in manufacturing data by traditional method is too long to meet requirement of quick defect analysis. Therefore, we present String Length Distribution Classification method (SLDC) to correctly classify strings in a short time. This method learns character features, especially string length distribution from Product ID, Machine ID in BOM and asset list. By applying the proposal to strings in actual manufacturing data, we verified that the classification time of strings can be reduced by 80%. As a result, it can be estimated that the requirement of quick defect analysis can be fulfilled.

Keywords: string classification, data quality, feature selection, probability distribution, string length

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17851 Studying the Impact of Architectural Styles on Student Satisfaction in University of Energy and Natural Resources, Sunyani

Authors: Frimpong Gyamfi Marious

Abstract:

At the University of Energy and Natural Resources (UENR) in Sunyani, Ghana, this study investigates the connection between architectural styles and student satisfaction. The study investigates how various architectural components, such as building layout, lighting, ventilation, and aesthetics, affect students' comfort, educational experience, and general contentment with campus amenities. Data was gathered using a mixed-methods approach that included physical inspections of school facilities, in-depth interviews with students, working and none working staff. According to the results, modern designs that incorporate flexible learning areas, sufficient natural lighting, and appropriate ventilation greatly raise student satisfaction. Nonetheless, it was discovered that certain traditional architectural features included in campus structures enhanced students' feelings of cultural kinship. The study also identifies key architectural challenges affecting student comfort, including inadequate thermal control and limited social interaction spaces. Based on these findings, the research proposes design recommendations for future campus development that balance modern functionality with cultural sensitivity. This study contributes to the growing body of knowledge on educational architecture and provides practical insights for improving campus design to enhance student experience in tropical climates.

Keywords: architecture, architectural styles, impact of architectural styles, impacts of architectural styles on students satisfaction

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17850 Comparative Study of Outcomes of Nonfixation of Mesh versus Fixation in Laparoscopic Total Extra Peritoneal (TEP) Repair of Inguinal Hernia: A Prospective Randomized Controlled Trial

Authors: Raman Sharma, S. K. Jain

Abstract:

Aims and Objectives: Fixation of the mesh during laparoscopic total extraperitoneal (TEP) repair of inguinal hernia is thought to be necessary to prevent recurrence. However, mesh fixation may increase surgical complications and postoperative pain. Our objective was to compare the outcomes of nonfixation with fixation of polypropylene mesh by metal tacks during TEP repair of inguinal hernia. Methods: Forty patients aged 18 to72 years with inguinal hernia were included who underwent laparoscopic TEP repair of inguinal hernia with (n=20) or without (n=20) fixation of the mesh. The outcomes were operative duration, postoperative pain score, cost, in-hospital stay, time to return to normal activity, and complications. Results: Patients in whom the mesh was not fixed had shorter mean operating time (p < 0.05). We found no difference between groups in the postoperative pain score, incidence of recurrence, in-hospital stay, time to return to normal activity and complications (P > 0.05). Moreover, a net cost savings was realized for each hernia repair performed without stapled mesh. Conclusions: TEP repair without mesh fixation resulted in the shorter operating time and lower operative cost with no difference between groups in the postoperative pain score, incidence of recurrence, in-hospital stay, time to return to normal activity and complications. All this contribute to make TEP repair without mesh fixation a better choice for repair of uncomplicated inguinal hernia, especially in developing nations with scarce resources.

Keywords: postoperative pain score, inguinal hernia, nonfixation of mesh, total extra peritoneal (TEP)

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17849 Evaluation of Durability Performance for Bio-Energy Co-Product

Authors: Bo Yang, Hali̇l Ceylan, Ali Ulvi̇ Uzer

Abstract:

This experimental study was performed to investigate the effect of biofuel co-products (BCPs) with sulfur-free lignin addition on the unconsolidated on strength and durability behavior in pavement soil stabilization subjected to freezing–thawing cycles. For strength behavior, a series of unconfined compression tests were conducted. Mass losses were also calculated after freezing–thawing cycles as criteria for durability behavior. To investigate the effect of the biofuel co-products on the durability behavior of the four type’s soils, mass losses were calculated after 12 freezing–thawing cycles. The co-products tested are promising additives for improving durability under freeze-thaw conditions, and each type has specific advantages.

Keywords: durability, mass lose, freezing–thawing test, bio-energy co-product, soil stabilization

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17848 Quality Control of 99mTc-Labeled Radiopharmaceuticals Using the Chromatography Strips

Authors: Yasuyuki Takahashi, Akemi Yoshida, Hirotaka Shimada

Abstract:

99mTc-2-methoxy-isobutyl-isonitrile (MIBI) and 99mTcmercaptoacetylgylcylglycyl-glycine (MAG3 ) are heat to 368-372K and are labeled with 99mTc-pertechnetate. Quality control (QC) of 99mTc-labeled radiopharmaceuticals is performed at hospitals, using liquid chromatography, which is difficult to perform in general hospitals. We used chromatography strips to simplify QC and investigated the effects of the test procedures on quality control. In this study is 99mTc- MAG3. Solvent using chloroform + acetone + tetrahydrofuran, and the gamma counter was ARC-380CL. The changed conditions are as follows; heating temperature, resting time after labeled, and expiration year for use: which were 293, 313, 333, 353 and 372K; 15 min (293K and 372K) and 1 hour (293K); and 2011, 2012, 2013, 2014 and 2015 respectively were tested. Measurement time using the gamma counter was one minute. A nuclear medical clinician decided the quality of the preparation in judging the usability of the retest agent. Two people conducted the test procedure twice, in order to compare reproducibility. The percentage of radiochemical purity (% RCP) was approximately 50% under insufficient heat treatment, which improved as the temperature and heating time increased. Moreover, the % RCP improved with time even under low temperatures. Furthermore, there was no deterioration with time after the expiration date. The objective of these tests was to determine soluble 99mTc impurities, including 99mTc-pertechnetate and the hydrolyzed-reduced 99mTc. Therefore, we assumed that insufficient heating and heating to operational errors in the labeling. It is concluded that quality control is a necessary procedure in nuclear medicine to ensure safe scanning. It is suggested that labeling is necessary to identify specifications.

Keywords: quality control, tc-99m labeled radio-pharmaceutical, chromatography strip, nuclear medicine

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17847 Adaptive Optimal Controller for Uncertain Inverted Pendulum System: A Dynamic Programming Approach for Continuous Time System

Authors: Dao Phuong Nam, Tran Van Tuyen, Do Trong Tan, Bui Minh Dinh, Nguyen Van Huong

Abstract:

In this paper, we investigate the adaptive optimal control law for continuous-time systems with input disturbances and unknown parameters. This paper extends previous works to obtain the robust control law of uncertain systems. Through theoretical analysis, an adaptive dynamic programming (ADP) based optimal control is proposed to stabilize the closed-loop system and ensure the convergence properties of proposed iterative algorithm. Moreover, the global asymptotic stability (GAS) for closed system is also analyzed. The theoretical analysis for continuous-time systems and simulation results demonstrate the performance of the proposed algorithm for an inverted pendulum system.

Keywords: approximate/adaptive dynamic programming, ADP, adaptive optimal control law, input state stability, ISS, inverted pendulum

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17846 Unsteady 3D Post-Stall Aerodynamics Accounting for Effective Loss in Camber Due to Flow Separation

Authors: Aritras Roy, Rinku Mukherjee

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The current study couples a quasi-steady Vortex Lattice Method and a camber correcting technique, ‘Decambering’ for unsteady post-stall flow prediction. The wake is force-free and discrete such that the wake lattices move with the free-stream once shed from the wing. It is observed that the time-averaged unsteady coefficient of lift sees a relative drop at post-stall angles of attack in comparison to its steady counterpart for some angles of attack. Multiple solutions occur at post-stall and three different algorithms to choose solutions in these regimes show both unsteadiness and non-convergence of the iterations. The distribution of coefficient of lift on the wing span also shows sawtooth. Distribution of vorticity changes both along span and in the direction of the free-stream as the wake develops over time with distinct roll-up, which increases with time.

Keywords: post-stall, unsteady, wing, aerodynamics

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17845 Moulding Photovoice to Community: Supporting Aboriginal People Experiencing Homelessness to Share Their Stories through Photography

Authors: Jocelyn Jones, Louise Southalan, Lindey Andrews, Mandy Wilson, Emma Vieira, Jackie Oakley, Dorothy Bagshaw, Alice V. Brown, Patrick Egan, Duc Dau, Lucy Spanswick

Abstract:

Working with people experiencing homelessness requires careful use of methods that support them to comfortably share their experiences. This is particularly important for Aboriginal and Torres Strait Islander peoples, the traditional owners of Australia, who have experienced intergenerational and compounding trauma since colonisation. Aboriginal cultures regularly experience research fatigue and distrust in research’s potential for impact. They often view research as an extraction -a process of taking the knowledge that empowers the research team and its institution, rather than benefiting those being researched. Through a partnership between an Aboriginal Community Controlled Organisation and a university research institute, we conducted a community-driven research project with 70-90 Aboriginal people experiencing homelessness in Perth, Western Australia. The project aimed to listen to and advocate for the voices of those who are experiencing homelessness, guided by the Aboriginal community. In consultation with Aboriginal Elders, we selected methods that are considered culturally safe, including those who would prefer to express their experiences creatively. This led us to run a series of Photovoice workshops -an established method that supports people to share their experiences through photography. This method treats participants as experts and is regularly used with marginalised groups across the world. We detail our experience and lessons in using Photovoice with Aboriginal community members experiencing homelessness. This includes the ways the method needed to be moulded to community needs and driven by their individual choices, such as being dynamic in the length of time participants would spend with us, how we would introduce the method to them, and providing support workers for participants when taking photos. We also discuss lessons in establishing and retaining engagement and how the method was successful in supporting participants to comfortably share their stories. Finally, we outline the insights into homelessness that the method offered, including highlighting the difficulty experienced by participants in transitioning from homelessness to accommodation and the diversity of hopes people who have experienced homelessness have for the future.

Keywords: Aboriginal and Torres Strait Islander peoples, photovoice, homelessness, community-led research

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17844 Synthesis, Characterization and Catalytic Applications of Divalent Schiff Base Metal Complexes Derived from Amino Coumarins and Substituted Benzaldehydes and Acetophenones

Authors: Srinivas Nerella

Abstract:

A series of new heterodentate N, O-donor ligands derived from condensing 3-amino Coumarins with hydroxy benzaldehydes and acetophenones were used to afford new mononuclear Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Pd(II) coordination compounds. All the complexes were characterized by IR, 1H-NMR, 13C-NMR, Mass, ESR, Electronic spectra, Conductance, Magnetic and Thermal studies. The ligands show hexa coordination in Mn(II), Co(II), Ni(II), and Pd(II) complexes resulting octahedral geometries, while the ligands in Zn(II) and Cu(II) complexes show tetra coordination resulting tetrahedral and square planar geometries respectively. These mononuclear complexes were investigated as catalysts in the hydrothiolation of aromatic and aliphatic alkynes with thiols. These metal complexes were acted as versatile catalysts and gave good yields.

Keywords: schiff bases, divalent metal complexes of schiff bases, Catalytic activity, hydrothiolation

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17843 Instructional Immediacy Practices in Asynchronous Learning Environment: Tutors' Perspectives

Authors: Samar Alharbi, Yota Dimitriadi

Abstract:

With the exponential growth of information and communication technologies in higher education, new online teaching strategies have become increasingly important for student engagement and learning. In particular, some institutions depend solely on asynchronous e-learning to provide courses for their students. The major challenge facing these institutions is how to improve the quality of teaching and learning in their asynchronous tools. One of the most important methods that can help e-learner to enhance their social learning and social presence in asynchronous learning setting is immediacy. This study explores tutors perceptions of their instructional immediacy practices as part of their communication actions in online learning environments. It was used a mixed-methods design under the umbrella of pragmatic philosophical assumption. The participants included tutors at an educational institution in a Saudi university. The participants were selected with a purposive sampling approach and chose an institution that offered fully online courses to students. The findings of the quantitative data show the importance of teachers’ immediacy practices in an online text-based learning environment. The qualitative data contained three main themes: the tutors’ encouragement of student interaction; their promotion of class participation; and their addressing of the needs of the students. The findings from these mixed methods can provide teachers with insights into instructional designs and strategies that they can adopt in order to use e-immediacy in effective ways, thus improving their students’ online learning experiences.

Keywords: asynchronous e-learning, higher education, immediacy, tutor

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17842 Study on Compressive Strength and Setting Time of Fly Ash Concrete after Slump Recovery Using Superplasticizer

Authors: Chaiyakrit Raoupatham, Ram Hari Dhakal, Chalermchai Wanichlamlert

Abstract:

Fresh concrete that is on bound to be rejected due to belated use either from delay construction process or unflavored traffic cause delay on concrete delivering can recover the slump and use once again by introduce second dose of superplasticizer(naphthalene based type F) into system. By adding superplasticizer as solution for recover unusable slump loss concrete may affects other concrete properties. Therefore, this paper was observed setting time and compressive strength of concrete after being re-dose with chemical admixture type F (superplasticizer, naphthalene based) for slump recovery. The concrete used in this study was fly ash concrete with fly ash replacement of 0%, 30% and 50% respectively. Concrete mix designed for test specimen was prepared with paste content (ratio of volume of cement to volume of void in the aggregate) of 1.2 and 1.3, water-to-binder ratio (w/b) range of 0.3 to 0.58, initial dose of superplasticizer (SP) range from 0.5 to 1.6%. The setting time of concrete were tested both before and after re-dosed with different amount of second dose and time of dosing. The research was concluded that addition of second dose of superplasticizer would increase both initial and final setting times accordingly to dosage of addition. As for fly ash concrete, the prolongation effect was higher as the replacement of fly ash is increase. The prolongation effect can reach up to maximum about 4 hours. In case of compressive strength, the re-dosed concrete has strength fluctuation within acceptable range of ±10%.

Keywords: compressive strength, fly ash concrete, second dose of superplasticizer, setting times

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17841 Origamic Forms: A New Realm in Improving Acoustical Environment

Authors: Mostafa Refat Ismail, Hazem Eldaly

Abstract:

The adaptation of architecture design to building function is getting highly needed in contemporary designs, especially with the great progression in design methods and tools. This, in turn, requires great flexibility in design strategies, as well as a wider spectrum of space settings to achieve the required environment that special activities imply. Acoustics is an essential factor influencing cognitive acts and behavior as well as, on the extreme end, the physical well-being inside a space. The complexity of this constrain is fueled up by the extended geometric dimensions of multipurpose halls, making acoustic adequateness a great concern that could not easily be achieved for each purpose. To achieve a performance oriented acoustic environment, various parametric shaped false ceilings based on origami folded notion are simulated. These parametric origami shapes are able to fold and unfold forming an interactive structure that changes the mutual acoustic environment according to the geometric shapes' position and its changing exposed surface areas. The mobility of the facets in the origami surface can stretch up the range from a complete plain surface to an unfolded element where a considerable amount of absorption is added to the space. The behavior of the parametric origami shapes are being modeled employing a ray tracing computer simulation package for various shapes topology. The conclusion shows a great variation in the acoustical performance due to the variation in folding faces of the origami surfaces, which cause different reflections and consequently large variations in decay curves.

Keywords: parametric, origami, acoustics, architecture

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17840 Noise Source Identification on Urban Construction Sites Using Signal Time Delay Analysis

Authors: Balgaisha G. Mukanova, Yelbek B. Utepov, Aida G. Nazarova, Alisher Z. Imanov

Abstract:

The problem of identifying local noise sources on a construction site using a sensor system is considered. Mathematical modeling of detected signals on sensors was carried out, considering signal decay and signal delay time between the source and detector. Recordings of noises produced by construction tools were used as a dependence of noise on time. Synthetic sensor data was constructed based on these data, and a model of the propagation of acoustic waves from a point source in the three-dimensional space was applied. All sensors and sources are assumed to be located in the same plane. A source localization method is checked based on the signal time delay between two adjacent detectors and plotting the direction of the source. Based on the two direct lines' crossline, the noise source's position is determined. Cases of one dominant source and the case of two sources in the presence of several other sources of lower intensity are considered. The number of detectors varies from three to eight detectors. The intensity of the noise field in the assessed area is plotted. The signal of a two-second duration is considered. The source is located for subsequent parts of the signal with a duration above 0.04 sec; the final result is obtained by computing the average value.

Keywords: acoustic model, direction of arrival, inverse source problem, sound localization, urban noises

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17839 Adaption Model for Building Agile Pronunciation Dictionaries Using Phonemic Distance Measurements

Authors: Akella Amarendra Babu, Rama Devi Yellasiri, Natukula Sainath

Abstract:

Where human beings can easily learn and adopt pronunciation variations, machines need training before put into use. Also humans keep minimum vocabulary and their pronunciation variations are stored in front-end of their memory for ready reference, while machines keep the entire pronunciation dictionary for ready reference. Supervised methods are used for preparation of pronunciation dictionaries which take large amounts of manual effort, cost, time and are not suitable for real time use. This paper presents an unsupervised adaptation model for building agile and dynamic pronunciation dictionaries online. These methods mimic human approach in learning the new pronunciations in real time. A new algorithm for measuring sound distances called Dynamic Phone Warping is presented and tested. Performance of the system is measured using an adaptation model and the precision metrics is found to be better than 86 percent.

Keywords: pronunciation variations, dynamic programming, machine learning, natural language processing

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17838 Grain Selection in Spiral Grain Selectors during Casting Single-Crystal Turbine Blades

Authors: M. Javahar, H. B. Dong

Abstract:

Single crystal components manufactured using Ni-base Superalloys are routinely used in the hot sections of aero engines and industrial gas turbines due to their outstanding high temperature strength, toughness and resistance to degradation in corrosive and oxidative environments. To control the quality of the single crystal turbine blades, particular attention has been paid to grain selection, which is used to obtain the single crystal morphology from a plethora of columnar grains. For this purpose, different designs of grain selectors are employed and the most common type is the spiral grain selector. A typical spiral grain selector includes a starter block and a spiral (helix) located above. It has been found that the grains with orientation well aligned to the thermal gradient survive in the starter block by competitive grain growth while the selection of the single crystal grain occurs in the spiral part. In the present study, 2D spiral selectors with different geometries were designed and produced using a state-of-the-art Bridgeman Directional Solidification casting furnace to investigate the competitive growth during grain selection in 2d grain selectors. The principal advantage of using a 2-D selector is to facilitate the wax injection process in investment casting by enabling significant degree of automation. The automation within the process can be derived by producing 2D grain selector wax patterns parts using a split die (metal mold model) coupled with wax injection stage. This will not only produce the part with high accuracy but also at an acceptable production rate.

Keywords: grain selector, single crystal, directional solidification, CMSX-4 superalloys, investment casting

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17837 Gradient-Based Reliability Optimization of Integrated Energy Systems Under Extreme Weather Conditions: A Case Study in Ningbo, China

Authors: Da LI, Peng Xu

Abstract:

Recent extreme weather events, such as the 2021 European floods and North American heatwaves, have exposed the vulnerability of energy systems to both extreme demand scenarios and potential physical damage. Current integrated energy system designs often overlook performance under these challenging conditions. This research, focusing on a regional integrated energy system in Ningbo, China, proposes a distinct design method to optimize system reliability during extreme events. A multi-scenario model was developed, encompassing various extreme load conditions and potential system damages caused by severe weather. Based on this model, a comprehensive reliability improvement scheme was designed, incorporating a gradient approach to address different levels of disaster severity through the integration of advanced technologies like distributed energy storage. The scheme's effectiveness was validated through Monte Carlo simulations. Results demonstrate significant enhancements in energy supply reliability and peak load reduction capability under extreme scenarios. The findings provide several insights for improving energy system adaptability in the face of climate-induced challenges, offering valuable references for building reliable energy infrastructure capable of withstanding both extreme demands and physical threats across a spectrum of disaster intensities.

Keywords: extreme weather events, integrated energy systems, reliability improvement, climate change adaptation

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17836 Evaluation of Immune Checkpoint Inhibitors in Cancer Therapy

Authors: Mir Mohammad Reza Hosseini

Abstract:

In new years immune checkpoint inhibitors have gathered care as being one of the greatest talented kinds of immunotherapy on the prospect. There has been a specific emphasis on the immune checkpoint molecules, cytotoxic T-lymphocyte antigen-4 (CTLA-4) and programmed cell death protein 1 (PD-1). In 2011, ipilimumab, the primary antibody obstructive an immune checkpoint (CTLA4) was authorized. It is now documented that recognized tumors have many devices of overpowering the antitumor immune response, counting manufacture of repressive cytokines, staffing of immunosuppressive immune cells, and upregulation of coinhibitory receptors recognized as immune checkpoints. This was fast followed by the growth of monoclonal antibodies directing PD1 (pembrolizumab and nivolumab) and PDL1 (atezolizumab and durvalumab). Anti-PD1/PDL1 antibodies have developed some of the greatest extensively set anticancer therapies. We also compare and difference their present place in cancer therapy and designs of immune-related toxicities and deliberate the role of dual immune checkpoint inhibition and plans for the organization of immune-related opposing proceedings. In this review, the employed code and present growth of numerous immune checkpoint inhibitors are abridged, while the communicating device and new development of Immune checkpoint inhibitors in cancer therapy-based synergistic therapies with additional immunotherapy, chemotherapy, phototherapy, and radiotherapy in important and clinical educations in the historical 5 years are portrayed and tinted. Lastly, we disapprovingly measure these methods and effort to find their fortes and faintness based on pre-clinical and clinical information.

Keywords: checkpoint, cancer therapy, PD-1, PDL-1, CTLA4, immunosuppressive

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