Search results for: subtle change detection and quantification
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10375

Search results for: subtle change detection and quantification

4195 A Tactic for a Cosmopolitan City Comparison through a Data-Driven Approach: Case of Climate City Networking

Authors: Sombol Mokhles

Abstract:

Tackling climate change requires expanding networking opportunities between a diverse range of cities to accelerate climate actions. Existing climate city networks have limitations in actively engaging “ordinary” cities in networking processes between cities, as they encourage a few powerful cities to be followed by the many “ordinary” cities. To reimagine the networking opportunities between cities beyond global cities, this paper incorporates “cosmopolitan comparison” to expand our knowledge of a diverse range of cities using a data-driven approach. Through a cosmopolitan perspective, a framework is presented on how to utilise large data to expand knowledge of cities beyond global cities to reimagine the existing hierarchical networking practices. The contribution of this framework is beyond urban climate governance but inclusive of different fields which strive for a more inclusive and cosmopolitan comparison attentive to the differences across cities.

Keywords: cosmopolitan city comparison, data-driven approach, climate city networking, urban climate governance

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4194 Faster Pedestrian Recognition Using Deformable Part Models

Authors: Alessandro Preziosi, Antonio Prioletti, Luca Castangia

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Deformable part models achieve high precision in pedestrian recognition, but all publicly available implementations are too slow for real-time applications. We implemented a deformable part model algorithm fast enough for real-time use by exploiting information about the camera position and orientation. This implementation is both faster and more precise than alternative DPM implementations. These results are obtained by computing convolutions in the frequency domain and using lookup tables to speed up feature computation. This approach is almost an order of magnitude faster than the reference DPM implementation, with no loss in precision. Knowing the position of the camera with respect to horizon it is also possible prune many hypotheses based on their size and location. The range of acceptable sizes and positions is set by looking at the statistical distribution of bounding boxes in labelled images. With this approach it is not needed to compute the entire feature pyramid: for example higher resolution features are only needed near the horizon. This results in an increase in mean average precision of 5% and an increase in speed by a factor of two. Furthermore, to reduce misdetections involving small pedestrians near the horizon, input images are supersampled near the horizon. Supersampling the image at 1.5 times the original scale, results in an increase in precision of about 4%. The implementation was tested against the public KITTI dataset, obtaining an 8% improvement in mean average precision over the best performing DPM-based method. By allowing for a small loss in precision computational time can be easily brought down to our target of 100ms per image, reaching a solution that is faster and still more precise than all publicly available DPM implementations.

Keywords: autonomous vehicles, deformable part model, dpm, pedestrian detection, real time

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4193 Women’s Leadership for Sustainable Outcomes: On the Road to Gender Equality for a Better Tomorrow

Authors: Deepika Faugoo

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Gender equality stands as the cornerstone of societal progress, intricately woven into the very essence of the 2030 Sustainable Development Goals (SDGs). Yet, the gender leadership gap remains a formidable obstacle hindering global equality. Despite women's educational advancements, their underrepresentation in senior roles persists as a baffling anomaly. Drawing from contemporary research, empirical evidence, and secondary data, this paper underscores the imperative of advancing women in leadership to drive SDGs related to empowerment and gender equality by 2030. It highlights the undeniable link between women leaders and sustainable outcomes, citing case studies and examples of their contributions to financial performance, prosperity, economic growth, and societal well-being. Exploring persistent barriers and emerging challenges, it offers actionable strategies to enhance women's representation in leadership, promising transformative benefits for organizations and societies. Amidst societal upheavals, gender equality emerges as a potent solution, catalyzing change toward a future where every voice resonates, ensuring no one is left behind.

Keywords: senior leadership, empowerment, SDGs, gender equality

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4192 Analysis of Vapor-Phase Diffusion of Benzene from Contaminated Soil

Authors: Asma A. Parlin, K. Nakamura, N. Watanabe, T. Komai

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Understanding the effective diffusion of benzene vapor in the soil-atmosphere interface is important as an intrusion of benzene into the atmosphere from the soil is largely driven by diffusion. To analyze the vertical one dimensional effective diffusion of benzene vapor in porous medium with high water content, diffusion experiments were conducted in soil columns using Andosol soil and Toyoura silica sand with different water content; for soil water content was from 0 to 30 wt.% and for sand it was from 0.06 to 10 wt.%. In soil, a linear relation was found between water content and effective diffusion coefficient while the effective diffusion coefficient didn’t change in the sand with increasing water. A numerical transport model following unsteady-state approaches based on Fick’s second law was used to match the required time for a steady state of the gas phase concentration profile of benzene to the experimentally measured concentration profile gas phase in the column. The result highlighted that both the water content and porosity might increase vertical diffusion of benzene vapor in soil.

Keywords: benzene vapor-phase, effective diffusion, subsurface soil medium, unsteady state

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4191 Reviewing Soil Erosion in Greece

Authors: Paschalis Koutalakis, George N. Zaimes, Valasia Iakovoglou, Konstantinos Ioannou

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Mitigating soil erosion, especially in Mediterranean countries such as Greece, is essential in order to maintain environmental and agricultural sustainability. In this paper, scientific publications related to soil erosion studies in Greece were reviewed and categorized. To accomplish this, the online search engine of Scopus was used. The key words were “soil”, “erosion” and “Greece.” An analysis of the published articles was conducted at three levels: i) type of publication, ii) chronologic and iii) thematic. A hundred and ten publications published in scientific journals were reviewed. The results showed that the awareness regarding the soil erosion in Greece has increased only in the last decades. The publications covered a wide range of thematic categories such as the type of studied areas, the physical phenomena that trigger and influence the soil erosion, the negative anthropogenic impacts on them, the assessment tools that were used in order to examine the threat and the proper management. The analysis of these articles was significant and necessary in order to find the scientific gaps of soil erosion studies in Greece and help enhance the sustainability of soil management in the future.

Keywords: climate change, agricultural sustainability, environmental sustainability, soil management

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4190 Investigating Convective Boiling Heat Transfer Characteristics of R-1234ze and R-134a Refrigerants in a Microfin and Smooth Tube

Authors: Kaggwa Abdul, Chi-Chuan Wang

Abstract:

This research is based on R-1234ze that is considered to substitute R-134a due to its low global warming potential in a microfin tube with outer diameter 9.52 mm, number of fins 70, and fin height 0.17 mm. In comparison, a smooth tube with similar geometries was used to study pressure drop and heat transfer coefficients related to the two fluids. The microfin tube was brazed inside a stainless steel tube and heated electrically. T-type thermocouples used to measure the temperature distribution during the phase change process. The experimental saturation temperatures and refrigerant mass velocities varied from 10 – 20°C and 50 – 300 kg/m2s respectively. The vapor quality from 0.1 to 0.9, and heat flux ranged from 5 – 11kW/m2. The results showed that heat transfer performance of R-134a in both microfin and smooth tube was better than R-1234ze especially at mass velocities above G = 50 kg/m2s. However, at low mass velocities below G = 100 kg/m2s R-1234ze yield better heat transfer coefficients than R-134a. The pressure gradient of R-1234ze was markedly higher than that of R-134a at all mass flow rates.

Keywords: R-1234ze and R-134a, horizontal flow boiling, pressure drop, heat transfer coefficients, micro-fin and smooth tubes

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4189 CO2 Mitigation by Promoting Solar Heating in Housing Sector

Authors: F. Sahnoune, M. Madani, M. Zelmat, M. Belhamel

Abstract:

Home heating and generation of domestic hot water are nowadays important items of expenditure and energy consumption. These are also a major source of pollution and emission of greenhouse gases (GHG). Algeria, like other countries of the southern shore of the Mediterranean has an enormous solar potential (more than 3000 hours of sunshine/year). This potential can be exploited in reducing GHG emissions and contribute to climate change adaptation. This work presents the environmental impact of introduction of solar heating in an individual house in Algerian climate conditions. For this purpose, we determined energy needs for heating and domestic hot water taking into account the thermic heat losses of the no isolated house. Based on these needs, sizing of the solar system was carried out. To compare the performances of solar and classic systems, we conducted also an economic evaluation what is very important for countries like Algeria where conventional energy is subsidized. The study clearly show that environmental and economic benefits are in favor of solar heating development in particular in countries where the thermal insulation of the building and energy efficiency are poorly developed.

Keywords: CO2 mitigation, solar energy, solar heating, environmental impact

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4188 Active-Material Variation Analysis of a Lithium-Ion Battery

Authors: Muhammad Husnat Khalid, Stephan Bihn, Dirk Uwe Sauer, Nisai Fuengwarodsakul

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To combat the effects of climate change, lithium-ion batteries are getting a lot of attention for energy storage. However, due to its diverse range of applications extending from small electronics equipment to energy storage systems, its output requirements, as well as limitations, vary significantly. Many efforts are underway to increase the power and energy output of the cells without any significant compromise on their size and weight. In this paper, different active materials are explored for an existing cell Kokam that initially has graphite as anode and NCO as cathode material. The Pareto front optimization tool is then utilized to pick a cell that gives the optimum results in terms of energy, power, or both. The parameter variation of the cells is done in the MATLAB application ISEA Cell and Pack Database (ICPD) created by the Institute of Power Electronics and Electrical Drives (ISEA) RWTH Aachen, University that creates the physical-chemical model of the existing cells.

Keywords: battery storage system, lithium-ion battery, active material variation, cell design optimization

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4187 Use of RAPD and ISSR Markers in Detection of Genetic Variation among Colletotrichum falcatum Went Isolates from South Gujarat India

Authors: Prittesh Patel, Rushabh Shah, Krishnamurthy Ramar, Vakulbhushan Bhaskar

Abstract:

The present research work aims at finding genetic differences in the genomes of sugarcane red rot isolates Colletotrichum falcatum Went using Random Amplified Polymorphic DNA (RAPD) and interspersed simple sequence repeat (ISSR) molecular markers. Ten isolates of C. falcatum isolated from different red rot infected sugarcane cultivars stalk were used in present study. The amplified bands were scored across the lanes obtained in 15 RAPD primes and 21 ISSR primes successfully. The data were analysed using NTSYSpc 2.2 software. The results showed 80.6% and 68.07% polymorphism in RPAD and ISSR analysis respectively. Based on the RAPD analysis, ten genotypes were grouped into two major clusters at a cut-off value of 0.75. Geographically distant C. falcatum isolate cfGAN from south Gujarat had a level of similarity with Coimbatore isolate cf8436 presented on separate clade of bootstrapped dendrograms. First and second cluster consisted of five and three isolates respectively, indicating the close relation among them. The 21 ISSR primers produced 119 distinct and scorable loci in that 38 were monomorphic. The number of scorable loci for each primer varied from 2 (ISSR822) to 8 (ISSR807, ISSR823 and ISSR15) with an average of 5.66 loci per primer. Primer ISSR835 amplified the highest number of bands (57), while only 16 bands were obtained by primers ISSR822. Four primers namely ISSR830, ISSR845, ISSR4 and ISSR15 showed the highest value of percentage of polymorphism (100%). The results indicated that both of the marker systems RAPD and ISSR, individually can be effectively used in determination of genetic relationship among C falcatum accessions collected from different parts of south Gujarat.

Keywords: Colletotrichum falcatum, ISSR, RAPD, Red Rot

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4186 International Solar Alliance: A Case for Indian Solar Diplomacy

Authors: Swadha Singh

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International Solar Alliance is the foremost treaty-based global organization concerned with tapping the potential of sun-abundant nations between the Tropics of Cancer and Capricorn and enables co-operation among them. As a founding member of the International Solar Alliance, India exhibits its positioning as an upcoming leader in clean energy. India has set ambitious goals and targets to expand the share of solar in its energy mix and is playing a proactive role both at the regional and global levels. ISA aims to serve multiple goals- bring about scale commercialization of solar power, boost domestic manufacturing, and leverage solar diplomacy in African countries, amongst others. Against this backdrop, this paper attempts to examine the ways in which ISA as an intergovernmental organization under Indian leadership can leverage the cause of clean energy (solar) diplomacy and effectively shape partnerships and collaborations with other developing countries in terms of sharing solar technology, capacity building, risk mitigation, mobilizing financial investment and providing an aggregate market. A more specific focus of ISA is on the developing countries, which in the absence of a collective, are constrained by technology and capital scarcity, despite being naturally endowed with solar resources. Solar rich but finance-constrained economies face political risk, foreign exchange risk, and off-taker risk. Scholars argue that aligning India’s climate change discourse and growth prospects in its engagements, collaborations, and partnerships at the bilateral, multilateral and regional level can help promote trade, attract investments, and promote resilient energy transition both in India and in partner countries. For developing countries, coming together in an action-oriented way on issues of climate and clean energy is particularly important since it is developing and underdeveloped countries that face multiple and coalescing challenges such as the adverse impact of climate change, uneven and low access to reliable energy, and pressing employment needs. Investing in green recovery is agreed to be an assured way to create resilient value chains, create sustainable livelihoods, and help mitigate climate threats. If India is able to ‘green its growth’ process, it holds the potential to emerge as a climate leader internationally. It can use its experience in the renewable sector to guide other developing countries in balancing multiple similar objectives of development, energy security, and sustainability. The challenges underlying solar expansion in India have lessons to offer other developing countries, giving India an opportunity to assume a leadership role in solar diplomacy and expand its geopolitical influence through inter-governmental organizations such as ISA. It is noted that India has limited capacity to directly provide financial funds and support and is not a leading manufacturer of cheap solar equipment, as does China; however, India can nonetheless leverage its large domestic market to scale up the commercialization of solar power and offer insights and learnings to similarly placed abundant solar countries. The paper examines the potential of and limits placed on India’s solar diplomacy.

Keywords: climate diplomacy, energy security, solar diplomacy, renewable energy

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4185 Influence of Angular Position of Unbalanced Force on Crack Breathing Mechanism

Authors: Roselyn Zaman, Mobarak Hossain

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A new mathematical model is developed to study crack breathing behavior considering effect of angular position of unbalanced force at different crack locations. Crack breathing behavior has been determined using effectual bending angle by studying the transient change of the crack area. Different crack breathing behavior of the unbalanced shaft has been observed for different combination of angular position of unbalanced force with crack location except crack locations 0.3L and 0.8335L, where L is the total length of the shaft, where unbalanced shaft behave completely like the balanced shaft. Based on different combination of angular position of unbalanced force with crack location, the stiffness of unbalanced shaft can be divided into three regions. An unbalanced shaft is overall stiffer than a balanced shaft when angular position of unbalance force is between 90° to 270° and crack located between 0.3L and 0.8335L, and it is overall flexible when the crack located in outside this crack region. On the other hand, it is overall flexible when angular position of unbalanced force is between 0° to 90° or 270° to 360° and crack located in middle region and it is overall stiffer for outside this crack region.

Keywords: cracked shaft, crack location, shaft stiffness, unbalanced force, and unbalanced force orientation

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4184 Investigation of Dynamic Characteristic of Planetary Gear Set Based On Three-Axes Torque Measurement

Authors: Masao Nakagawa, Toshiki Hirogaki, Eiichi Aoyama, Mohamed Ali Ben Abbes

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A planetary gear set is widely used in hybrid vehicles as the power distribution system or in electric vehicles as the high reduction system, but due to its complexity with planet gears, its dynamic characteristic is not fully understood. There are many reports on two-axes driving or displacement of the planet gears under these conditions, but only few reports deal with three-axes driving. A three-axes driving condition is tested using three-axes torque measurement and focuses on the dynamic characteristic around the planet gears in this report. From experimental result, it was confirmed that the transition forces around the planet gears were balanced and the torques were also balanced around the instantaneous rotation center. The meshing frequency under these conditions was revealed to be the harmonics of two meshing frequencies; meshing frequency of the ring gear and that of the planet gears. The input power of the ring gear is distributed to the carrier and the sun gear in the dynamic sequential change of three fixed conditions; planet, star and solar modes.

Keywords: dynamic characteristic, gear, planetary gear set, torque measuring

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4183 Slipping Through the Net: Women’s Experiences of Maternity Services and Social Support in the UK During the COVID-19 Pandemic

Authors: Freya Harding, Anne Gatuguta, Chi Eziefula

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Introduction Research shows the quality of experiences of pregnancy, birth, and postpartum impacts the health and well-being of the mother and baby. This is recognised by the WHO in their recommendations ‘Intrapartum care for a positive childbirth experience’. The COVID-19 pandemic saw the transformation of the NHS Maternity services to prevent the transmission of COVID-19. Physical and social isolation may have affected women’s experiences of pregnancy, birth and postpartum; especially those of healthcare. Examples of such changes made to the NHS include both the reduction in volume of face-to-face consultations and restrictions to visitor time in hospitals. One notable detriment due to these changes was the absence of a partner during certain stages of birth. The aim of this study was to explore women’s experiences of pregnancy, birth, and postnatal period during the COVID-19 pandemic in the UK. Methods We collected qualitative data from women who had given birth during the COVID-19 pandemic. In-depth, semi-structured interviews were conducted with twelve participants recruited from mother and baby groups in Southeast England. Data were audio-recorded, transcribed verbatim, and analysed thematically using both inductive and deductive approaches. Ethics permission was granted from Brighton and Sussex Medical School (ER/BSMS9A83/1). Results Interviews were conducted with 12 women who gave birth between May 2020 and February 2021. Ages of the participants ranged between 28 and 42 years, most of which were white British, with one being Asian British. All participants were heterosexual and either married or co-habiting with their partner. Five participants worked in the NHS, and all participants had professional occupations. Women felt inadequately supported both socially and medically. An appropriate sense of control over their own birthing experience was lacking. Safety mechanisms, such as in-person visits from the midwife, had no suitable alternatives in place. Serious health issues were able to “slip through the net.” Mental health conditions in some of those interviewed worsened or developed. Similarly, reduced support from partners during birth and during the immediate postpartum period at the hospital, coupled with reduced ward staffing, resulted in some traumatic experiences; particularly for women who had undergone caesarean section. However, some unexpected positive effects were reported; one example being that partners were able to spend more time with their baby due to furlough schemes and working from home. Similarly, emergency care was not felt to have been compromised. Overall, six themes emerged: (1) Self-reported traumatic experiences, (2) Challenges of caring for a baby with reduced medical and social support, (3) Unexpected benefits to the parenting experience, (4) The effects of a sudden change in medical management (5) Poor communication from healthcare professionals (6) Social change; with subthemes of support accessing medical care, the workplace, family and friends, and antenatal & baby groups. Conclusions The results indicate that the healthcare system was unable to adequately deliver maternity care to facilitate positive pregnancy, birth, and postnatal experiences during the heights of the pandemic. The poor quality of such experiences has been linked an increased risk of long-term health complications in both the mother and child.

Keywords: pregnancy, birth, postpartum, postnatal, COVID-19, maternity, social support, qualitative, pandemic

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4182 Effects of Injection Conditions on Flame Structures in Gas-Centered Swirl Coaxial Injector

Authors: Wooseok Song, Sunjung Park, Jongkwon Lee, Jaye Koo

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The objective of this paper is to observe the effects of injection conditions on flame structures in gas-centered swirl coaxial injector. Gaseous oxygen and liquid kerosene were used as propellants. For different injection conditions, two types of injector, which only differ in the diameter of the tangential inlet, were used in this study. In addition, oxidizer injection pressure was varied to control the combustion chamber pressure in different types of injector. In order to analyze the combustion instability intensity, the dynamic pressure was measured in both the combustion chamber and propellants lines. With the increase in differential pressure between the propellant injection pressure and the combustion chamber pressure, the combustion instability intensity increased. In addition, the flame structure was recorded using a high-speed camera to detect CH* chemiluminescence intensity. With the change in the injection conditions in the gas-centered swirl coaxial injector, the flame structure changed.

Keywords: liquid rocket engine, flame structure, combustion instability, dynamic pressure

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4181 Digital Holographic Interferometric Microscopy for the Testing of Micro-Optics

Authors: Varun Kumar, Chandra Shakher

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Micro-optical components such as microlenses and microlens array have numerous engineering and industrial applications for collimation of laser diodes, imaging devices for sensor system (CCD/CMOS, document copier machines etc.), for making beam homogeneous for high power lasers, a critical component in Shack-Hartmann sensor, fiber optic coupling and optical switching in communication technology. Also micro-optical components have become an alternative for applications where miniaturization, reduction of alignment and packaging cost are necessary. The compliance with high-quality standards in the manufacturing of micro-optical components is a precondition to be compatible on worldwide markets. Therefore, high demands are put on quality assurance. For quality assurance of these lenses, an economical measurement technique is needed. For cost and time reason, technique should be fast, simple (for production reason), and robust with high resolution. The technique should provide non contact, non-invasive and full field information about the shape of micro- optical component under test. The interferometric techniques are noncontact type and non invasive and provide full field information about the shape of the optical components. The conventional interferometric technique such as holographic interferometry or Mach-Zehnder interferometry is available for characterization of micro-lenses. However, these techniques need more experimental efforts and are also time consuming. Digital holography (DH) overcomes the above described problems. Digital holographic microscopy (DHM) allows one to extract both the amplitude and phase information of a wavefront transmitted through the transparent object (microlens or microlens array) from a single recorded digital hologram by using numerical methods. Also one can reconstruct the complex object wavefront at different depths due to numerical reconstruction. Digital holography provides axial resolution in nanometer range while lateral resolution is limited by diffraction and the size of the sensor. In this paper, Mach-Zehnder based digital holographic interferometric microscope (DHIM) system is used for the testing of transparent microlenses. The advantage of using the DHIM is that the distortions due to aberrations in the optical system are avoided by the interferometric comparison of reconstructed phase with and without the object (microlens array). In the experiment, first a digital hologram is recorded in the absence of sample (microlens array) as a reference hologram. Second hologram is recorded in the presence of microlens array. The presence of transparent microlens array will induce a phase change in the transmitted laser light. Complex amplitude of object wavefront in presence and absence of microlens array is reconstructed by using Fresnel reconstruction method. From the reconstructed complex amplitude, one can evaluate the phase of object wave in presence and absence of microlens array. Phase difference between the two states of object wave will provide the information about the optical path length change due to the shape of the microlens. By the knowledge of the value of the refractive index of microlens array material and air, the surface profile of microlens array is evaluated. The Sag of microlens and radius of curvature of microlens are evaluated and reported. The sag of microlens agrees well within the experimental limit as provided in the specification by the manufacturer.

Keywords: micro-optics, microlens array, phase map, digital holographic interferometric microscopy

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4180 Impact of Mammographic Screening on Ethnic Inequalities in Breast Cancer Stage at Diagnosis and Survival in New Zealand

Authors: Sanjeewa Seneviratne, Ian Campbell, Nina Scott, Ross Lawrenson

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Introduction: Indigenous Māori women experience a 60% higher breast cancer mortality rate compared with European women in New Zealand. We explored the impact of difference in the rate of screen detected breast cancer between Māori and European women on more advanced disease at diagnosis and lower survival in Māori women. Methods: All primary in-situ and invasive breast cancers diagnosed in screening age women (as defined by the New Zealand National Breast Cancer Screening Programme) between 1999 and 2012 in the Waikato area were identified from the Waikato Breast Cancer Register and the national screening database. Association between screen versus non-screen detection and cancer stage at diagnosis and survival were compared by ethnicity and socioeconomic deprivation. Results: Māori women had 50% higher odds of being diagnosed with more advance staged cancer compared with NZ European women, a half of which was explained by the lower rate of screen detected cancer in Māori women. Significantly lower breast cancer survival rates were observed for Māori compared with NZ European and most deprived compared with most affluent socioeconomic groups for symptomatically detected breast cancer. No significant survival differences by ethnicity or socioeconomic deprivation were observed for screen detected breast cancer. Conclusions: Low rate of screen detected breast cancer appears to be a major contributor for more advanced stage disease at diagnosis and lower breast cancer survival in Māori compared with NZ European women. Increasing screening participation for Māori has the potential to substantially reduce breast cancer mortality inequity between Māori and NZ European women.

Keywords: breast cancer, screening, ethnicity, inequity

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4179 Effect of Wind and Humidity on Microwave Links in North West Libya

Authors: M. S. Agha, A. M. Eshahiry, S. A. Aldabbar, Z. M. Alshahri

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The propagation of microwave is affected by rain and dust particles causing signal attenuation and de-polarization. Computations of these effects require knowledge of the propagation characteristics of microwave and millimeter wave energy in the climate conditions of the studied region. This paper presents effect of wind and humidity on wireless communication such as microwave links in the North West region of Libya (Al-Khoms). The experimental procedure is done on three selected antennae towers (Nagaza station, Al-Khoms center station, Al-Khoms gateway station) for determining the attenuation loss per unit length and cross-polarization discrimination (XPD) change. Dust particles are collected along the region of the study, to measure the particle size distribution (PSD), calculate the concentration, and chemically analyze the contents, then the dielectric constant can be calculated. The results show that humidity and dust, antenna height and the visibility affect both attenuation and phase shift; in which, a few considerations must be taken into account in the communication power budget.

Keywords: : Attenuation, scattering, transmission loss.

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4178 Educational Audit and Curricular Reforms in the Arabian Context

Authors: Irum Naz

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In the Arabian higher education context, linguistic proficiency in the English language is considered crucial for the developmental sustainability, economic growth, and stability of communities and societies. Qatar’s educational reforms package, through the 2030 vision, identifies the acquisition of English at K-12 as an essential survival communication tool for globalization, believing that Qatari students need better preparation to take on the responsibilities of leadership and to participate effectively in the country’s surging economy. The idea of introducing Qatari students to modern curricula benchmarked to high-student-performance curricula in developed countries is one of the components of reformatory design principles of Education for New Era reform project that is mutually consented to and supported by the Office of Shared Services, Communications Office, and Supreme Education Council. In appreciation of the government’s vision, the English Language Centre (ELC) at the Community College of Qatar ran an internal educational audit and conducted evaluative research to understand and appraise the value, impact, and practicality of the existing ELC language development program. This study sought to identify the type of change that could identify and improve the quality of Foundation Program courses and the manners in which second language learners could be assisted to transit smoothly between (ELC) levels. Following the interpretivist paradigm and mixed research method, the data was gathered through a bicyclic research model and a triangular design. The analyses of the data suggested that there was a need for improvement in the ELC program as a whole, and particularly in terms of curriculum, student learning outcomes, and the general learning environment in the department. Key findings suggest that the target program would benefit from significant revisions, which would include narrowing the focus of the courses, providing sets of specific learning objectives, and preventing repetition between levels. Another promising finding was about the assessment tools and process. The data suggested that a set of standardized assessments that more closely suited the programs of study should be devised. It was also recommended that students undergo a more comprehensive placement process to ensure that they begin the program at an appropriate level and get the maximum benefit from their learning experience. Although this ties into the idea of curriculum revamp, it was expected that students could leave the ELC having had exposure to courses in English for specific purposes. The idea of a more reliable exit assessment for students was raised frequently so ELC could regulate itself and ensure optimum learning outcomes. Another important recommendation was the provision of a Student Learning Center for students that would help them to receive personalized tuition, differentiated instruction, and self-driven and self-evaluated learning experience. In addition, an extra study level was recommended to be added to the program to accommodate the different levels of English language proficiency represented among ELC students. The evidence collected in the course of conducting the study suggests that significant change is needed in the structure of the ELC program, specifically about curriculum, the program learning outcomes, and the learning environment in general.

Keywords: educational audit, ESL, optimum learning outcomes, Qatar’s educational reforms, self-driven and self-evaluated learning experience, Student Learning Center

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4177 Low-Level Forced and Ambient Vibration Tests on URM Building Strengthened by Dampers

Authors: Rafik Taleb, Farid Bouriche, Mehdi Boukri, Fouad Kehila

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The aim of the paper is to investigate the dynamic behavior of an unreinforced masonry (URM) building strengthened by DC-90 dampers by ambient and low-level forced vibration tests. Ambient and forced vibration techniques are usually applied to reinforced concrete or steel buildings to understand and identify their dynamic behavior, however, less is known about their applicability for masonry buildings. Ambient vibrations were measured before and after strengthening of the URM building by DC-90 dampers system. For forced vibration test, a series of low amplitude steady state harmonic forced vibration tests were conducted after strengthening using eccentric mass shaker. The resonant frequency curves, mode shapes and damping coefficients as well as stress distribution in the steel braces of the DC-90 dampers have been investigated and could be defined. It was shown that the dynamic behavior of the masonry building, even if not regular and with deformable floors, can be effectively represented. It can be concluded that the strengthening of the building does not change the dynamic properties of the building due to the fact of low amplitude excitation which do not activate the dampers.

Keywords: ambient vibrations, masonry buildings, forced vibrations, structural dynamic identification

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4176 Numerical Study of Nonlinear Guided Waves in Composite Laminates with Delaminations

Authors: Reza Soleimanpour, Ching Tai Ng

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Fibre-composites are widely used in various structures due to their attractive properties such as higher stiffness to mass ratio and better corrosion resistance compared to metallic materials. However, one serious weakness of this composite material is delamination, which is a subsurface separation of laminae. A low level of this barely visible damage can cause a significant reduction in residual compressive strength. In the last decade, the application of guided waves for damage detection has been a topic of significant interest for many researches. Among all guided wave techniques, nonlinear guided wave has shown outstanding sensitivity and capability for detecting different types of damages, e.g. cracks and delaminations. So far, most of researches on applications of nonlinear guided wave have been dedicated to isotropic material, such as aluminium and steel, while only a few works have been done on applications of nonlinear characteristics of guided waves in anisotropic materials. This study investigates the nonlinear interactions of the fundamental antisymmetric lamb wave (A0) with delamination in composite laminates using three-dimensional (3D) explicit finite element (FE) simulations. The nonlinearity considered in this study arises from interactions of two interfaces of sub-laminates at the delamination region, which generates contact acoustic nonlinearity (CAN). The aim of this research is to investigate the phenomena of CAN in composite laminated beams by a series of numerical case studies. In this study interaction of fundamental antisymmetric lamb wave with delamination of different sizes are studied in detail. The results show that the A0 lamb wave interacts with the delaminations generating CAN in the form of higher harmonics, which is a good indicator for determining the existence of delaminations in composite laminates.

Keywords: contact acoustic nonlinearity, delamination, fibre reinforced composite beam, finite element, nonlinear guided waves

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4175 Renegotiating International Contract Clauses: The Case of Investment Environment Changes in Egypt

Authors: Marwa Zein

Abstract:

The long-term of the contract is one of the major features that distinguish international trade and investment contracts from other internal contracts. This is due to the nature of the contract and the huge works required to be performed from one hand or the desire of the parties to achieve stability in their transactions. However, long-term contracts might expose them to certain events and circumstances that impact the capability of the parties to execute their obligations pursuant to these contracts. During the year 2016, the Egyptian government has taken series of economic decisions which greatly impacted the economic and investment environment. Consequently, many contracts have encountered many problems in their execution due to such changes that greatly influence the performance of their obligation, a matter that necessitated the renegotiation of the conditions of these contracts on the basis of the unpredicted changes that could be listed under the Force Majeure Clause. The principle of fair and equitable treatment in investment placed on an obligation on the Egyptian government to consider the renegotiation of contract clauses based on the new conditions. This paper will discuss the idea of renegotiating international trade and investment contracts in Egypt with reference to the changes the economic environment has witnessed lately.

Keywords: change of circumstances, international contracts, investment contracts, renegotiation

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4174 High Resolution Sandstone Connectivity Modelling: Implications for Outcrop Geological and Its Analog Studies

Authors: Numair Ahmed Siddiqui, Abdul Hadi bin Abd Rahman, Chow Weng Sum, Wan Ismail Wan Yousif, Asif Zameer, Joel Ben-Awal

Abstract:

Advances in data capturing from outcrop studies have made possible the acquisition of high-resolution digital data, offering improved and economical reservoir modelling methods. Terrestrial laser scanning utilizing LiDAR (Light detection and ranging) provides a new method to build outcrop based reservoir models, which provide a crucial piece of information to understand heterogeneities in sandstone facies with high-resolution images and data set. This study presents the detailed application of outcrop based sandstone facies connectivity model by acquiring information gathered from traditional fieldwork and processing detailed digital point-cloud data from LiDAR to develop an intermediate small-scale reservoir sandstone facies model of the Miocene Sandakan Formation, Sabah, East Malaysia. The software RiScan pro (v1.8.0) was used in digital data collection and post-processing with an accuracy of 0.01 m and point acquisition rate of up to 10,000 points per second. We provide an accurate and descriptive workflow to triangulate point-clouds of different sets of sandstone facies with well-marked top and bottom boundaries in conjunction with field sedimentology. This will provide highly accurate qualitative sandstone facies connectivity model which is a challenge to obtain from subsurface datasets (i.e., seismic and well data). Finally, by applying this workflow, we can build an outcrop based static connectivity model, which can be an analogue to subsurface reservoir studies.

Keywords: LiDAR, outcrop, high resolution, sandstone faceis, connectivity model

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4173 Environmental Evaluation of Alternative/Renewable Fuels Technology

Authors: Muhammad Hadi Ibrahim

Abstract:

The benefits of alternative/renewable fuels in general and a study of the environmental impacts of biofuels in particular have been reviewed in this paper. It is a known fact that, energy generation using fossil fuel produces many important pollutants including; nitrogen oxides, hydrocarbons, soot, dust, smoke and other particulate harmful matter. It’s believed that if carbon dioxide levels continue to increase drastically, the planet will become warmer and will most likely result in a variety of negative impacts including; sea-level rise, extreme and unpredictable weather events and an increased frequency of draughts in inland agricultural zones. Biofuels such as alcohols, biogas, etc. appear to be more viable alternatives, especially for use as fuels in diesel engines. The substitution of fossil fuel through increased utilization of biofuels produced in a sustainable manner, can contribute immensely towards a cleaner environment, reduction in greenhouse gas emissions and mitigation of climate change. Stakeholders in the energy sector can be sensitized by the findings of the research study and to consider the possible adverse effects in developing technologies for the production and combustion of biofuels.

Keywords: emission, energy, renewable/alternative fuel, environment, pollution

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4172 High School Gain Analytics From National Assessment Program – Literacy and Numeracy and Australian Tertiary Admission Rankin Linkage

Authors: Andrew Laming, John Hattie, Mark Wilson

Abstract:

Nine Queensland Independent high schools provided deidentified student-matched ATAR and NAPLAN data for all 1217 ATAR graduates since 2020 who also sat NAPLAN at the school. Graduating cohorts from the nine schools contained a mean 100 ATAR graduates with previous NAPLAN data from their school. Excluded were vocational students (mean=27) and any ATAR graduates without NAPLAN data (mean=20). Based on Index of Community Socio-Educational Access (ICSEA) prediction, all schools had larger that predicted proportions of their students graduating with ATARs. There were an additional 173 students not releasing their ATARs to their school (14%), requiring this data to be inferred by schools. Gain was established by first converting each student’s strongest NAPLAN domain to a statewide percentile, then subtracting this result from final ATAR. The resulting ‘percentile shift’ was corrected for plausible ATAR participation at each NAPLAN level. Strongest NAPLAN domain had the highest correlation with ATAR (R2=0.58). RESULTS School mean NAPLAN scores fitted ICSEA closely (R2=0.97). Schools achieved a mean cohort gain of two ATAR rankings, but only 66% of students gained. This ranged from 46% of top-NAPLAN decile students gaining, rising to 75% achieving gains outside the top decile. The 54% of top-decile students whose ATAR fell short of prediction lost a mean 4.0 percentiles (or 6.2 percentiles prior to correction for regression to the mean). 71% of students in smaller schools gained, compared to 63% in larger schools. NAPLAN variability in each of the 13 ICSEA1100 cohorts was 17%, with both intra-school and inter-school variation of these values extremely low (0.3% to 1.8%). Mean ATAR change between years in each school was just 1.1 ATAR ranks. This suggests consecutive school cohorts and ICSEA-similar schools share very similar distributions and outcomes over time. Quantile analysis of the NAPLAN/ATAR revealed heteroscedasticity, but splines offered little additional benefit over simple linear regression. The NAPLAN/ATAR R2 was 0.33. DISCUSSION Standardised data like NAPLAN and ATAR offer educators a simple no-cost progression metric to analyse performance in conjunction with their internal test results. Change is expressed in percentiles, or ATAR shift per student, which is layperson intuitive. Findings may also reduce ATAR/vocational stream mismatch, reveal proportions of cohorts meeting or falling short of expectation and demonstrate by how much. Finally, ‘crashed’ ATARs well below expectation are revealed, which schools can reasonably work to minimise. The percentile shift method is neither value-add nor a growth percentile. In the absence of exit NAPLAN testing, this metric is unable to discriminate academic gain from legitimate ATAR-maximizing strategies. But by controlling for ICSEA, ATAR proportion variation and student mobility, it uncovers progression to ATAR metrics which are not currently publicly available. However achieved, ATAR maximisation is a sought-after private good. So long as standardised nationwide data is available, this analysis offers useful analytics for educators and reasonable predictivity when counselling subsequent cohorts about their ATAR prospects.  

Keywords: NAPLAN, ATAR, analytics, measurement, gain, performance, data, percentile, value-added, high school, numeracy, reading comprehension, variability, regression to the mean

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4171 Medical Diagnosis of Retinal Diseases Using Artificial Intelligence Deep Learning Models

Authors: Ethan James

Abstract:

Over one billion people worldwide suffer from some level of vision loss or blindness as a result of progressive retinal diseases. Many patients, particularly in developing areas, are incorrectly diagnosed or undiagnosed whatsoever due to unconventional diagnostic tools and screening methods. Artificial intelligence (AI) based on deep learning (DL) convolutional neural networks (CNN) have recently gained a high interest in ophthalmology for its computer-imaging diagnosis, disease prognosis, and risk assessment. Optical coherence tomography (OCT) is a popular imaging technique used to capture high-resolution cross-sections of retinas. In ophthalmology, DL has been applied to fundus photographs, optical coherence tomography, and visual fields, achieving robust classification performance in the detection of various retinal diseases including macular degeneration, diabetic retinopathy, and retinitis pigmentosa. However, there is no complete diagnostic model to analyze these retinal images that provide a diagnostic accuracy above 90%. Thus, the purpose of this project was to develop an AI model that utilizes machine learning techniques to automatically diagnose specific retinal diseases from OCT scans. The algorithm consists of neural network architecture that was trained from a dataset of over 20,000 real-world OCT images to train the robust model to utilize residual neural networks with cyclic pooling. This DL model can ultimately aid ophthalmologists in diagnosing patients with these retinal diseases more quickly and more accurately, therefore facilitating earlier treatment, which results in improved post-treatment outcomes.

Keywords: artificial intelligence, deep learning, imaging, medical devices, ophthalmic devices, ophthalmology, retina

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4170 Predicting Marital Burnout Based on Irrational Beliefs and Sexual Dysfunction of Couples

Authors: Elnaz Bandeh

Abstract:

This study aimed to predict marital burnout based on irrational beliefs and sexual dysfunction of couples. The research method was descriptive-correlational, and the statistical population included all couples who consulted to counseling clinics in the fall of 2016. The sample consisted of 200 people who were selected by convenience sampling and answered the Ahwaz Irrational Beliefs Questionnaire, Pines Couple Burnout, and Hudson Marital Satisfaction Questionnaire. The data were analyzed using regression coefficient. The results of regression analysis showed that there was a linear relationship between irrational beliefs and couple burnout and dimensions of helplessness toward change, expectation of approval from others, and emotional irresponsibility were positive and significant predictors of couple burnout. However, after avoiding the problem of power, it was not a significant predictor of marital dissatisfaction. There was also a linear relationship between sexual dysfunction and couple burnout, and sexual dysfunction was a positive and significant predictor of couple burnout. Based on the findings, it can be concluded that irrational beliefs and sexual dysfunction play a role in couple dysfunction.

Keywords: couple burnout, irrational beliefs, sexual dysfunction, marital relationship

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4169 Qualitative Analysis of Bituminous Mix Modified by Polypropylene and Impact Characteristics on Pavement Wearing Course

Authors: Jayisha Das Jaya, Nafis As Sami, Nazia Jahan, Tamanna Jerin, Mohammed Russedul Islam

Abstract:

This paper contains continuous research which helps to analyze polypropylene modified bituminous mix and its impact characteristics with respect to original bitumen. Three percentages of polypropylene varying from (1-3) % of the weight of bitumen have been used to alter bitumen’s performance. The temperature of 170°C has been maintained during the blending of polypropylene with bitumen. It was performed by a wet process as it has certain advantages over the dry process. A rough estimate of 210 rpm rotation speed was set to prepare the blend in a mixer for 30 minutes producing homogeneous mixture. The blended mix shows a change in physical properties in comparison with the original bitumen content. Modification shows that for a 1% increment of polypropylene, softening point increases by 1 degree, penetration values decrease gradually to 55.6, 54, 52.5, ductility values decrease gradually to 87,76, 63 and specific gravity remains the same. Then Marshall mix design is performed with 60/70 penetration grade bitumen contents varying from (4-6) % with .5% intervals. Marshall stability and flow test results indicate the increase in stability and decrease in flow.

Keywords: bitumen, marshall, polypropylene, temperature

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4168 More Than a Game: An Educational Application Where Students Compete to Learn

Authors: Kadir Özsoy

Abstract:

Creating a moderately competitive learning environment is believed to have positive effects on student interest and motivation. The best way today to attract young learners to get involved in a fun, competitive learning experience is possible through mobile applications as these learners mostly rely on games and applications on their phones and tablets to have fun, communicate, look for information and study. In this study, a mobile application called ‘QuizUp’ is used to create a specific game topic for elementary level students at Anadolu University Preparatory School. The topic is specially designed with weekly-added questions in accordance with the course syllabus. Students challenge their classmates or randomly chosen opponents to answer questions related to their course subjects. They also chat and post on the topic’s wall in English. The study aims at finding out students’ perceptions towards the use of the application as a classroom and extra-curricular activity through a survey. The study concludes that educational games boost students’ motivation, lead to increased effort, and positively change their studying habits.

Keywords: competitive learning, educational application, effort, motivation 'QuizUp', study habits

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4167 NiO-CeO2 Nano-Catalyst for the Removal of Priority Organic Pollutants from Wastewater through Catalytic Wet Air Oxidation at Mild Conditions

Authors: Anushree, Chhaya Sharma, Satish Kumar

Abstract:

Catalytic wet air oxidation (CWAO) is normally carried out at elevated temperature and pressure. This work investigates the potential of NiO-CeO2 nano-catalyst in CWAO of paper industry wastewater under milder operating conditions of 90 °C and 1 atm. The NiO-CeO2 nano-catalysts were synthesized by a simple co-precipitation method and characterized by X-ray diffraction (XRD), before and after use, in order to study any crystallographic change during experiment. The extent of metal-leaching from the catalyst was determined using the inductively coupled plasma optical emission spectrometry (ICP-OES). The catalytic activity of nano-catalysts was studied in terms of total organic carbon (TOC), adsorbable organic halides (AOX) and chlorophenolics (CHPs) removal. Interestingly, mixed oxide catalysts exhibited higher activity than the corresponding single-metal oxides. The maximum removal efficiency was achieved with Ce40Ni60 catalyst. The results indicate that the CWAO process is efficient in removing the priority organic pollutants from wastewater, as it exhibited up to 59% TOC, 55% AOX, and 54 % CHPs removal.

Keywords: catalysis, nano-materials, NiO-CeO2, paper mill, wastewater, wet air oxidation

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4166 Sandstone-Hosted Copper Mineralization in Oligo-Miocene-Red-Bed Strata, Chalpo North East of Iran: Constraints from Lithostratigraphy, Lithogeochemistry, Mineralogy, Mass Change Technique, and Ree Distribution

Authors: Mostafa Feiz, Hossein Hadizadeh, Mohammad Safari

Abstract:

The Chalpo copper area is located in northeastern Iran, which is part of the structural zone of central Iran and the back-arc basin of Sabzevar. This sedimentary basin accumulated in destructive-Oligomiocene sediments is named the Nasr-Chalpo-Sangerd (NCS) basin. The sedimentary layers in this basin originated mainly from Upper Cretaceous ophiolitic rocks and intermediate to mafic-post ophiolitic volcanic rocks, deposited as a nonconformity. The mineralized sandstone layers in the Chalpo area include leached zones (with a thickness of 5 to 8 meters) and mineralized lenses with a thickness of 0.5 to 0.7 meters. Ore minerals include primary sulfide minerals, such as chalcocite, chalcopyrite, and pyrite, as well as secondary minerals, such as covellite, digenite, malachite, and azurite, formed in three stages that comprise primary, simultaneously, and supergene stage. The best agents that control the mineralization in this area include the permeability of host rocks, the presence of fault zones as the conduits for copper oxide solutions, and significant amounts of plant fossils, which create a reducing environment for the deposition of mineralized layers. Statistical studies on copper layers indicate that Ag, Cd, Mo, and S have the maximum positive correlation with Cu, whereas TiO₂, Fe₂O₃, Al₂O₃, Sc, Tm, Sn, and the REEs have a negative correlation. The calculations of mass changes on copper-bearing layers and primary sandstone layers indicate that Pb, As, Cd, Te, and Mo are enriched in the mineralized zones, whereas SiO₂, TiO₂, Fe₂O₃, V, Sr, and Ba are depleted. The combination of geological, stratigraphic, and geochemical studies suggests that the origin of copper may have been the underlying red strata that contained hornblende, plagioclase, biotite, alkaline feldspar, and labile minerals. Dehydration and hydrolysis of these minerals during the diagenetic process caused the leaching of copper and associated elements by circling fluids, which formed an oxidant-hydrothermal solution. Copper and silver in this oxidant solution might have moved upwards through the basin-fault zones and deposited in the reducing environments in the sandstone layers that have had abundant organic matters. Copper in these solutions probably was carried by chloride complexes. The collision of oxidant and reduced solutions caused the deposition of Cu and Ag, whereas some stable elements in oxidant environments (e.g., Fe₂O₃, TiO₂, SiO₂, REEs) become unstable in the reduced condition. Therefore, the copper-bearing sandstones in the study area are depleted from these elements resulting from the leaching process. The results indicate that during the mineralization stage, LREEs and MREEs were depleted, but Cu, Ag, and S were enriched. Based on field evidence, it seems that the circulation of connate fluids in the reb-bed strata, produced by diagenetic processes, encountered to reduced facies, which formed earlier by abundant fossil-plant debris in the sandstones, is the best model for precipitating sulfide-copper minerals.

Keywords: Chalpo, oligo-miocene red beds, sandstone-hosted copper mineralization, mass change, LREEs, MREEs

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