Search results for: efficiency of quality assessment
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 19247

Search results for: efficiency of quality assessment

13577 Characterization of Carbazole-Based Host Material for Highly Efficient Thermally Activated Delayed Fluorescence Emitter

Authors: Malek Mahmoudi, Jonas Keruckas, Dmytro Volyniuk, Jurate Simokaitiene, Juozas V. Grazulevicius

Abstract:

Host materials have been discovered as one of the most appealing methods for harvesting triplet states in organic materials for application in organic light-emitting diodes (OLEDs). The ideal host-guest system for emission in thermally delayed fluorescence OLEDs with 20% guest concentration for efficient energy transfer has been demonstrated in the present investigation. In this work, 3,3'-bis[9-(4-fluorophenyl) carbazole] (bFPC) has been used as the host, which induces balanced charge carrier transport for high-efficiency OLEDs.For providing a complete characterization of the synthesized compound, photophysical, photoelectrical, charge-transporting, and electrochemical properties of the compound have been examined. Excited-state lifetimes and singlet-triplet energy gaps were measured for characterization of photophysical properties, while thermogravimetric analysis, as well as differential scanning calorimetry measurements, were performed for probing of electrochemical and thermal properties of the compound. The electrochemical properties of this compound were investigated by cyclic voltammetry (CV) method, and ionization potential (IPCV) value of 5.68 eV was observed. UV–Vis absorption and photoluminescence spectrum of a solution of the compound in toluene (10-5 M) showed maxima at 302 and 405 nm, respectively. Photoelectron emission spectrometry was used for the characterization of charge-injection properties of the studied compound in solid. The ionization potential of this material was found to be 5.78 eV, and time-of-flight measurement was used for testing charge-transporting properties and hole mobility estimated using this technique in a vacuum-deposited layer reached 4×10-4 cm2 V-1s-1. Since the compound with high charge mobilities was tested as a host in an organic light-emitting diode. The device was fabricated by successive deposition onto a pre-cleaned indium tin oxide (ITO) coated glass substrate under a vacuum of 10-6 Torr and consisting of an indium-tin-oxide anode, hole injection and transporting layer(MoO3, NPB), emitting layer with bFPC as a host and 4CzIPN (2,4,5,6-tetra(9-carbazolyl)isophthalonitrile) which is a new highly efficient green thermally activated delayed fluorescence (TADF) material as an emitter, an electron transporting layer(TPBi) and lithium fluoride layer topped with aluminum layer as a cathode exhibited the highest maximum current efficiency and power efficiency of 33.9 cd/A and 23.5 lm/W, respectively and the electroluminescence spectrum showed only a peak at 512nm. Furthermore, the new bicarbazole-based compound was tested as a host in thermally activated delayed fluorescence organic light-emitting diodes are reaching luminance of 25300 cd m-2 and external quantum efficiency of 10.1%. Interestingly, the turn-on voltage was low enough (3.8 V), and such a device can be used for highly efficient light sources.

Keywords: thermally-activated delayed fluorescence, host material, ionization energy, charge mobility, electroluminescence

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13576 Overall Assessment of Human Research and Ethics Committees in the United Arab Emirates

Authors: Mahera Abdulrahman, Satish Chandrasekhar Nair

Abstract:

Growing demand for human health research in the United Arab Emirates (UAE) has prompted the need to develop a robust research ethics oversight, particularly given the large unskilled-worker immigrant population and the elderly citizens utilizing health services. Examination of the structure, function, practices and outcomes of the human research ethics committees (HREC) was conducted using two survey instruments, reliable and validated. Results indicate that in the absence of a national ethics regulatory body, the individual emirate’s governed 21 HRECs covering health facilities and academic institutions in the UAE. Among the HRECs, 86% followed International Council for Harmonization-Good Clinical Practice guidelines, 57% have been in operation for more than five years, 81% reviewed proposals within eight weeks, 48% reviewed for clinical and scientific merit apart from ethics, and 43% handled more than 50 research proposals per year. However, researcher recognition, funding transparency, adverse event reporting systems were widespread in less than one-third of all HRECs. Surprisingly, intellectual property right was not included as a research output. Research was incorporated into the vision and mission statements of many (62%) organizations and, mechanisms such as research publications, collaborations, and recognitions were employed as key performance indicators to measure research output. In spite, resources to generate research output such as dedicated budget (19%), support staff (19%) and continuous training and mentoring program for medical residents and HREC members were somehow lacking. HREC structure and operations in the UAE are similar to other regions of the world, resources allocation for efficient, quality monitoring, continuous training, and the creation of a clinical research network are needed to strengthen the clinical research enterprise to scale up for the future. It is anticipated that the results of this study will benefit investigators, regulators, pharmaceutical sponsors and the policy makers in the region.

Keywords: institutional review board, ethics committee, human research ethics, United Arab Emirates (UAE)

Procedia PDF Downloads 209
13575 Thermal Management of Ground Heat Exchangers Applied in High Power LED

Authors: Yuan-Ching Chiang, Chien-Yeh Hsu, Chen Chih-Hao, Sih-Li Chen

Abstract:

The p-n junction temperature of LEDs directly influences their operating life and luminous efficiency. An excessively high p-n junction temperature minimizes the output flux of LEDs, decreasing their brightness and influencing the photon wavelength; consequently, the operating life of LEDs decreases and their luminous output changes. The maximum limit of the p-n junction temperature of LEDs is approximately 120 °C. The purpose of this research was to devise an approach for dissipating heat generated in a confined space when LEDs operate at low temperatures to reduce light decay. The cooling mode of existing commercial LED lights can be divided into natural- and forced convection cooling. In natural convection cooling, the volume of LED encapsulants must be increased by adding more fins to increase the cooling area. However, this causes difficulties in achieving efficient LED lighting at high power. Compared with forced convection cooling, heat transfer through water convection is associated with a higher heat transfer coefficient per unit area; therefore, we dissipated heat by using a closed loop water cooling system. Nevertheless, cooling water exposed to air can be easily influenced by environmental factors. Thus, we incorporated a ground heat exchanger into the water cooling system to minimize the influence of air on cooling water and then observed the relationship between the amounts of heat dissipated through the ground and LED efficiency.

Keywords: helical ground heat exchanger, high power LED, ground source cooling system, heat dissipation

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13574 Blind Super-Resolution Reconstruction Based on PSF Estimation

Authors: Osama A. Omer, Amal Hamed

Abstract:

Successful blind image Super-Resolution algorithms require the exact estimation of the Point Spread Function (PSF). In the absence of any prior information about the imagery system and the true image; this estimation is normally done by trial and error experimentation until an acceptable restored image quality is obtained. Multi-frame blind Super-Resolution algorithms often have disadvantages of slow convergence and sensitiveness to complex noises. This paper presents a Super-Resolution image reconstruction algorithm based on estimation of the PSF that yields the optimum restored image quality. The estimation of PSF is performed by the knife-edge method and it is implemented by measuring spreading of the edges in the reproduced HR image itself during the reconstruction process. The proposed image reconstruction approach is using L1 norm minimization and robust regularization based on a bilateral prior to deal with different data and noise models. A series of experiment results show that the proposed method can outperform other previous work robustly and efficiently.

Keywords: blind, PSF, super-resolution, knife-edge, blurring, bilateral, L1 norm

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13573 Measuring the Extent of Equalization in Fiscal Transfers in India: An Index-Based Approach

Authors: Ragini Trehan, D.K. Srivastava

Abstract:

In the post-planning era, India’s fiscal transfers from the central to state governments are solely determined by the Finance Commissions (FCs). While in some of the well-established federations such as Australia, Canada, and Germany, equalization serves as the guiding principle of fiscal transfers and is constitutionally mandated, in India, it is not explicitly mandated, and FCs attempt to implement it indirectly by a combination of a formula-based share in the divisible pool of central taxes supplemented by a set of grants. In this context, it is important to measure the extent of equalization that is achieved through FC transfers with a view to improving the design of such transfers. This study uses an index-based methodology for measuring the degree of equalization achieved through FC-transfers covering the period from FC12 to the first year of FC15 spanning from 2005-06 to 2020-21. The ‘Index of Equalization’ shows that the extent of equalization has remained low in the range of 30% to 37% for the four Commission periods under review. The highest degree of equalization at 36.7% was witnessed in the FC12 period and the lowest equalization at 29.5% was achieved during the FC15(1) period. The equalizing efficiency of recommended transfers also shows a consistent fall from 11.4% in the FC12 period to 7.5% by the FC15 (1) period. Further, considering progressivity in fiscal transfers as a special case of equalizing transfers, this study shows that the scheme of per capita total transfers when determined using the equalization approach is more progressive and is characterized by minimal deviations as compared to the profile of transfers recommended by recent FCs.

Keywords: fiscal transfers, index of equalization, equalizing efficiency, fiscal capacity, expenditure needs, finance Commission, tax effort

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13572 Systems Approach on Thermal Analysis of an Automatic Transmission

Authors: Sinsze Koo, Benjin Luo, Matthew Henry

Abstract:

In order to increase the performance of an automatic transmission, the automatic transmission fluid is required to be warm up to an optimal operating temperature. In a conventional vehicle, cold starts result in friction loss occurring in the gear box and engine. The stop and go nature of city driving dramatically affect the warm-up of engine oil and automatic transmission fluid and delay the time frame needed to reach an optimal operating temperature. This temperature phenomenon impacts both engine and transmission performance but also increases fuel consumption and CO2 emission. The aim of this study is to develop know-how of the thermal behavior in order to identify thermal impacts and functional principles in automatic transmissions. Thermal behavior was studied using models and simulations, developed using GT-Suit, on a one-dimensional thermal and flow transport. A power train of a conventional vehicle was modeled in order to emphasis the thermal phenomena occurring in the various components and how they impact the automatic transmission performance. The simulation demonstrates the thermal model of a transmission fluid cooling system and its component parts in warm-up after a cold start. The result of these analyses will support the future designs of transmission systems and components in an attempt to obtain better fuel efficiency and transmission performance. Therefore, these thermal analyses could possibly identify ways that improve existing thermal management techniques with prioritization on fuel efficiency.

Keywords: thermal management, automatic transmission, hybrid, and systematic approach

Procedia PDF Downloads 365
13571 Objective Evaluation on Medical Image Compression Using Wavelet Transformation

Authors: Amhimmid Mohammed Saffour, Mustafa Mohamed Abdullah

Abstract:

The use of computers for handling image data in the healthcare is growing. However, the amount of data produced by modern image generating techniques is vast. This data might be a problem from a storage point of view or when the data is sent over a network. This paper using wavelet transform technique for medical images compression. MATLAB program, are designed to evaluate medical images storage and transmission time problem at Sebha Medical Center Libya. In this paper, three different Computed Tomography images which are abdomen, brain and chest have been selected and compressed using wavelet transform. Objective evaluation has been performed to measure the quality of the compressed images. For this evaluation, the results show that the Peak Signal to Noise Ratio (PSNR) which indicates the quality of the compressed image is ranging from (25.89db to 34.35db for abdomen images, 23.26db to 33.3db for brain images and 25.5db to 36.11db for chest images. These values shows that the compression ratio is nearly to 30:1 is acceptable.

Keywords: medical image, Matlab, image compression, wavelet's, objective evaluation

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13570 Comparison of the Existing Damage Indices in Steel Moment-Resisting Frame Structures

Authors: Hamid Kazemi, Abbasali Sadeghi

Abstract:

Assessment of seismic behavior of frame structures is just done for evaluating life and financial damages or lost. The new structural seismic behavior assessment methods have been proposed, so it is necessary to define a formulation as a damage index, which the damage amount has been quantified and qualified. In this paper, four new steel moment-resisting frames with intermediate ductility and different height (2, 5, 8, and 12-story) with regular geometry and simple rectangular plan were supposed and designed. The three existing groups’ damage indices were studied, each group consisting of local index (Drift, Maximum Roof Displacement, Banon Failure, Kinematic, Banon Normalized Cumulative Rotation, Cumulative Plastic Rotation and Ductility), global index (Roufaiel and Meyer, Papadopoulos, Sozen, Rosenblueth, Ductility and Base Shear), and story (Banon Failure and Inter-story Rotation). The necessary parameters for these damage indices have been calculated under the effect of far-fault ground motion records by Non-linear Dynamic Time History Analysis. Finally, prioritization of damage indices is defined based on more conservative values in terms of more damageability rate. The results show that the selected damage index has an important effect on estimation of the damage state. Also, failure, drift, and Rosenblueth damage indices are more conservative indices respectively for local, story and global damage indices.

Keywords: damage index, far-fault ground motion records, non-linear time history analysis, SeismoStruct software, steel moment-resisting frame

Procedia PDF Downloads 281
13569 Initiative Programme to Reform Education in Thailand

Authors: Piyapat Chitpirom, Teerakiat Jareonsettasin, Chintida Vichitsophaphan

Abstract:

The Foundation of Virtuous Youth was established and supported by the Crown Property Bureau, with the intention to instill goodness in Thai youth. The Centre for Educational Psychology is one of the three units under the foundation. We aim to develop programmes that can be used to improve the quality of education in schools. Translation of the King’s message in keeping with the modern research from various sources, our team create 6 programmes: (1) Teacher-Student Relationship (2) Growth Mindset (3) Socratic Teaching (4) Peer Tutoring (5) Parental Involvement (6) Inclusion. After nine months of implementing the programmes in the schools, we found that there were more cooperation between student-student, teacher-student, teacher-parent, and student-parent and the school regained trust from the community. Our ideas were accepted well by the government as our director was promoted to be the Vice Minister of Education in order to implement our programmes into national education system. We consider that the key of our success is that we do practical things. We are still continuing, improving, and learning from our work with hope that the quality of Thai education will improve in near future.

Keywords: education reform, educational psychology, effective teaching, teacher-student relationship

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13568 Device for Mechanical Fragmentation of Organic Substrates Before Methane Fermentation

Authors: Marcin Zieliński, Marcin Dębowski, Mirosław Krzemieniewski

Abstract:

This publication presents a device designed for mechanical fragmentation of plant substrate before methane fermentation. The device is equipped with a perforated rotary cylindrical drum coated with a thermal layer, connected to a substrate feeder and driven by a motoreducer. The drum contains ball- or cylinder-shaped weights of different diameters, while its interior is mounted with lateral permanent magnets with an attractive force ranging from 100 kg to 2 tonnes per m2 of the surface. Over the perforated rotary drum, an infrared radiation generator is mounted, producing 0.2 kW to 1 kW of infrared radiation per 1 m2 of the perforated drum surface. This design reduces the energy consumption required for the biomass destruction process by 10-30% in comparison to the conventional ball mill. The magnetic field generated by the permanent magnets situated within the perforated rotary drum promotes this process through generation of free radicals that act as powerful oxidants, accelerating the decomposition rate. Plant substrate shows increased susceptibility to biodegradation when subjected to magnetic conditioning, reducing the time required for biomethanation by 25%. Additionally, the electromagnetic radiation generated by the radiator improves substrate destruction by 10% and the efficiency of the process. The magnetic field and the infrared radiation contribute synergically to the increased efficiency of destruction and conversion of the substrate.

Keywords: biomass pretreatment, mechanical fragmentation, biomass, methane fermentation

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13567 The Challenge of the Decarbonization of Shipping and Complex Imo Regulations

Authors: Saiyeed Jakaria Baksh Imran

Abstract:

The earth is being endangered by many of the climate related issues today. The most serious issue for the world today is the global warming. Increase in Greenhouse gas (GHG) emissions post-industrial revolution period is the prime reason for global warming. Shipping is the fifth largest GHG emitting sector worldwide. The key reason for this is because, over 90% of the world trade is conducted through ocean as the ocean alone covers 70% of the earth surface. While the countries continue to develop, trade and commerce continue to increase between them simultaneously. However, there is no sign of reduction in GHG emission from shipping because of many concerned issues. Firstly, there is technological barrier for which ships cannot just become environment friendly immediately. Secondly, there is no alternative fuel available as well. Thirdly, there is no proper mechanism to measure how much ships emit as emission from ships vary according to the size, engine type and loading capacity of ships. The International Maritime Organization (IMO) being the governing body of the international shipping has implemented MARPOL Annex VI. However, the policy alone is not enough unless there is a proper data available regarding ship emissions, which the IMO is yet to figure out. This paper will present a critical analysis of existing IMO policies such as the Energy Efficiency Design Index (EEDI), Ship Energy Efficiency Management Plan (SEEMP), Data Collection System (SEEMP) and the IMO’s Initial Strategy on Reduction of Greenhouse Gas emissions from shipping. Also, the challenges exist in implementing such policies have been presented in the paper.

Keywords: GHG, IMO, EEDI, SEEMP, DCS, greenhouse gas, decarbonization, shipping

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13566 Assessment of the Fertility Status of the Fadama Soils Found along Five Major River Catchments in Kano

Authors: Garba K. Adamu

Abstract:

This research was carried out in the catchments of five major rivers in Kano State. The catchments have considerable Fadama lands; these include: River Gari which is located in the northwestern part of Kano state, Rivers Challawa and Watari from southernparts of Kano and Katsina states. River Tomas from the northern parts of Kano state, River Jakara which has its source from the Old Kano city, part of Central Business Districts and Industrial Estates. The study was carried out with aim of assessing the fertility status of the Fadama soils found in these major river catchments. A transect was designed to collect samples along farming villages in the five river channels for the study. The findings indicate that the soils are predominantly sandy. The bulk density values vary significantly and range from 0.98mg/m to 1.36mg/m. The pH values for all the sites studied ranges from slightly acidic to slightly alkaline. The OC ranged from low to very low in the sites. The EC ranges from 66.3µs/cm to 198µs/cm for all the sites. The mean CEC ranges from 3.864 cm/kg to 10.114 Cmol/kg. The range of values for the SAR was 0.0106 to 0.069. Nitrogen ranges from0.03 to 0.1230ppm. The range of P value fell between 9.9 to 41.1mg/kg.Ca values ranges from 1.0170 to 14.9850 and K values ranges from 4.6550 – 64.40.Mg values range from 0.1380 to 1.8580 and Zn values range from 1.0170 to 14.9850. The Fe values ranged from 15.6500mg/kg to 69.8000mg/kg. The B values range from0.2060 to13.5450. Generally, the values obtained shows a low to medium fertility levels for all the parameters tested and the areas will require the in cooperation of organic manure and chemical fertilizers to improve soil structure and supplements other macro nutrients.

Keywords: assessment, Fadama soils, fertility status, river catchment

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13565 Improving Data Completeness and Timely Reporting: A Joint Collaborative Effort between Partners in Health and Ministry of Health in Remote Areas, Neno District, Malawi

Authors: Wiseman Emmanuel Nkhomah, Chiyembekezo Kachimanga, Moses Banda Aron, Julia Higgins, Manuel Mulwafu, Kondwani Mpinga, Mwayi Chunga, Grace Momba, Enock Ndarama, Dickson Sumphi, Atupere Phiri, Fabien Munyaneza

Abstract:

Background: Data is key to supporting health service delivery as stakeholders, including NGOs rely on it for effective service delivery, decision-making, and system strengthening. Several studies generated debate on data quality from national health management information systems (HMIS) in sub-Saharan Africa. This limits the utilization of data in resource-limited settings, which already struggle to meet standards set by the World Health Organization (WHO). We aimed to evaluate data quality improvement of Neno district HMIS over a 4-year period (2018 – 2021) following quarterly data reviews introduced in January 2020 by the district health management team and Partners In Health. Methods: Exploratory Mixed Research was used to examine report rates, followed by in-depth interviews using Key Informant Interviews (KIIs) and Focus Group Discussions (FGDs). We used the WHO module desk review to assess the quality of HMIS data in the Neno district captured from 2018 to 2021. The metrics assessed included the completeness and timeliness of 34 reports. Completeness was measured as a percentage of non-missing reports. Timeliness was measured as the span between data inputs and expected outputs meeting needs. We computed T-Test and recorded P-values, summaries, and percentage changes using R and Excel 2016. We analyzed demographics for key informant interviews in Power BI. We developed themes from 7 FGDs and 11 KIIs using Dedoose software, from which we picked perceptions of healthcare workers, interventions implemented, and improvement suggestions. The study was reviewed and approved by Malawi National Health Science Research Committee (IRB: 22/02/2866). Results: Overall, the average reporting completeness rate was 83.4% (before) and 98.1% (after), while timeliness was 68.1% and 76.4 respectively. Completeness of reports increased over time: 2018, 78.8%; 2019, 88%; 2020, 96.3% and 2021, 99.9% (p< 0.004). The trend for timeliness has been declining except in 2021, where it improved: 2018, 68.4%; 2019, 68.3%; 2020, 67.1% and 2021, 81% (p< 0.279). Comparing 2021 reporting rates to the mean of three preceding years, both completeness increased from 88% to 99% (in 2021), while timeliness increased from 68% to 81%. Sixty-five percent of reports have maintained meeting a national standard of 90%+ in completeness while only 24% in timeliness. Thirty-two percent of reports met the national standard. Only 9% improved on both completeness and timeliness, and these are; cervical cancer, nutrition care support and treatment, and youth-friendly health services reports. 50% of reports did not improve to standard in timeliness, and only one did not in completeness. On the other hand, factors associated with improvement included improved communications and reminders using internal communication, data quality assessments, checks, and reviews. Decentralizing data entry at the facility level was suggested to improve timeliness. Conclusion: Findings suggest that data quality in HMIS for the district has improved following collaborative efforts. We recommend maintaining such initiatives to identify remaining quality gaps and that results be shared publicly to support increased use of data. These results can inform Ministry of Health and its partners on some interventions and advise initiatives for improving its quality.

Keywords: data quality, data utilization, HMIS, collaboration, completeness, timeliness, decision-making

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13564 The Impact of the Business Process Reengineering on the Practices of the Human Resources Management in the Franco Tunisian Company-Network

Authors: Nesrine Bougarech, Habib Affes

Abstract:

This research lays the emphasis on the business process reengineering (BPR) which consists in radically altering the organizational processes through the optimal use of information technology (IT) to attain major enhancements in terms of quality, performance and productivity. A survey of the business process reengineering (BPR) was carried out in three French groups and their subsidiaries in Tunisia. The data collected were qualitatively analyzed in an attempt to test the main indicators of the success of a business process reengineering project (BPR) and to compare the importance of these indicators in the context of France versus Tunisia. The study corroborates that the respect of the inherent principles of the business process reengineering (BPR) and the diversity of the human resources involved in the project can lead to better productivity, higher quality of the goods or services and lower cost. Additionally, our results mirror the extent to which the respect of the principles and the diversity of resources are more important in the French companies than in their Tunisian subsidiaries.

Keywords: business process reengineering (BPR), human resources management (HRM), information technology (IT), management

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13563 A Real Time Set Up for Retrieval of Emotional States from Human Neural Responses

Authors: Rashima Mahajan, Dipali Bansal, Shweta Singh

Abstract:

Real time non-invasive Brain Computer Interfaces have a significant progressive role in restoring or maintaining a quality life for medically challenged people. This manuscript provides a comprehensive review of emerging research in the field of cognitive/affective computing in context of human neural responses. The perspectives of different emotion assessment modalities like face expressions, speech, text, gestures, and human physiological responses have also been discussed. Focus has been paid to explore the ability of EEG (Electroencephalogram) signals to portray thoughts, feelings, and unspoken words. An automated workflow-based protocol to design an EEG-based real time Brain Computer Interface system for analysis and classification of human emotions elicited by external audio/visual stimuli has been proposed. The front end hardware includes a cost effective and portable Emotive EEG Neuroheadset unit, a personal computer and a set of external stimulators. Primary signal analysis and processing of real time acquired EEG shall be performed using MATLAB based advanced brain mapping toolbox EEGLab/BCILab. This shall be followed by the development of MATLAB based self-defined algorithm to capture and characterize temporal and spectral variations in EEG under emotional stimulations. The extracted hybrid feature set shall be used to classify emotional states using artificial intelligence tools like Artificial Neural Network. The final system would result in an inexpensive, portable and more intuitive Brain Computer Interface in real time scenario to control prosthetic devices by translating different brain states into operative control signals.

Keywords: brain computer interface, electroencephalogram, EEGLab, BCILab, emotive, emotions, interval features, spectral features, artificial neural network, control applications

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13562 Quality of Today's Teachers: Post-Certified Teachers' Competence in Alleviating Poverties towards a Sustainable Development

Authors: Sudirman

Abstract:

Competence is a term describing capability that correlates with a person’s occupation. The competence of a teacher consists of four, i.e., pedagogical, professional, personality and social competence. These four components are implemented during interacting with students to motivate the students and improve their achievement. The objective of this qualitative study is to explore the roles and contributions of certified teachers in alleviating the issue of poverty to promote a sustainable development. The data comprise primary and secondary data which were generated from observation, interview, documentation and library research. Furthermore, this study offers in-depth information regarding the performance of the teachers in coping with poverty and sustaining development. The result shows that the teacher’s competence positively contributes to the improvement of students’ achievement. This helps the students to prepare for the real work experience by which it results in a better income and, therefore, alleviate poverty. All in all, the quality of today’s teachers can be measured by their contribution in enhancing the students’ competence prior to entering real work, resulting in a wealthy society. This is to deal with poverty and conceptualizing a sustainable development.

Keywords: competence, development, poverty, teachers

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13561 Evaluation of Chromium Fortified - Parboiled Rice Coated with Herbal Extracts: Cooking Quality and Sensory Properties

Authors: Wisnu Adi Yulianto, Agus Slamet, Sri Luwihana, Septian Albar Dwi Suprayogi

Abstract:

Parboiled rice was developed to produce rice, which has a low glycemic index for diabetics. However, diabetics also have a chromium (Cr) deficiency. Thus, it is important to fortify rice with Cr to increase the Cr content. Moreover, parboiled rice becomes rancid easily and has a musty odor, rendering the rice unfavorable. Natural herbs such as pandan leaves (Pandanus amaryllifolius Roxb.), bay leaves (Syzygium polyanthum [Wigh] Walp) and cinnamon bark powder (Cinnamomon cassia) are commonly added to food as aroma enhancers. Previous research has shown that these herbs could improve insulin sensitivity. The purpose of this study was to evaluate the effect of herbal extract coatings on the cooking quality and the preference level of chromium fortified - parboiled rice (CFPR). The rice grain variety used for this experiment was Ciherang and the fortificant was CrCl3. The three herbal extracts used for coating the CFPR were cinnamon, pandan and bay leaf, with concentration variations of 3%, 6%, and 9% (w/w) for each of the extracts. The samples were analyzed for their alkali spreading value, cooking time, elongation, water uptake ratio, solid loss, colour and lightness; and their sensory properties were determined by means of an organoleptic test. The research showed that coating the CFPR with pandan and cinnamon extracts at a concentration of 3% each produced a preferred CFPR. When coated with those herbal extracts the CFPR had the following cooking quality properties: alkali spreading value 5 (intermediate gelatinization temperature), cooking time, 26-27 min, color value, 14.95-15.00, lightness, 42.30 – 44.06, elongation, 1.53 – 1.54, water uptake ratio , 4.05-4.06, and solid loss, 0.09/100 g – 0.13 g/100 g.

Keywords: bay leaves, chromium, cinnamon, pandan leaves, parboiled rice

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13560 Assessment of the Physicochemical Qualities and Prevalence of Vibrio Pathogens in the Final Effluents of Two Wastewater Treatment Plants in Eastern Cape Province, South Africa

Authors: C. A Osunla, A. I. Okoh

Abstract:

Treated wastewater effluent has been found to encompass high levels of pollutants, including disease-causing bacteria such as Vibrio pathogens. The current study was designed to evaluate the physicochemical qualities and prevalence of Vibrio pathogens in treated effluents of two wastewater treatment plants (WWTP) in Eastern Cape Province, South Africa over the period of six months. Parameters measured include pH, temperature, electrical conductivity, salinity, turbidity, total dissolved solid (TDS), dissolved oxygen (DO), and free chlorine; and these parameters were simultaneously monitored in the treated final effluents of the two wastewater treatment plants using standard methods. The ranges of values for the physicochemical are: pH (7.0–8.6), total dissolved solids (286.3–916.5 mg/L), electrical conductivity (572.57–1704.5 mS/m), temperature (10.3–28.6 °C), turbidity (4.02–43.20 NTU), free chlorine (0.00–0.19 mg/L), dissolve oxygen (2.06–6.32 mg/L) and biochemical oxygen demand (0.1–9.0 mg/L). The microbiological assessment for both WWTPs revealed the presence of Vibrio counts ranging between 0 and 8.76×104 CFU/100 mL. The obtained values of the measured parameters and Vibrio loads of the treated wastewater effluents were found outside the compliance levels of the South African guidelines and World Health Organization tolerance limits for effluents intended to be discharged into receiving waterbodies. Hence, we conclude that these WWTPs are important point sources of pollution in surface water with potential public health and ecological risks.

Keywords: effluents, public health, South Africa, Vibrio, wastewater

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13559 The Effects of Smoking Prevention Intervention on Smoking Knowledge, Attitudes and Anti-Smoking Self-Efficiency among Adolescent Students

Authors: Yi-Ying Lin, Su-Guo, Chia-Hao, Ming-Szu Hong

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Objectives: Smoking is a common addictive behavior in teenagers. Long-term smoking is hazardous to health, causes family and social expenditure, and is an important topic that should not be overlooked by academia or the government. The aims of this study are to examine the effectiveness of these courses in terms of teenagers’ knowledge and attitudes towards the hazards of smoking and the effectiveness of their self-efficacy in rejecting smoking. Methods: This study adopted a pre-test post-test design and selected 7th, 8th, 10th, and 11th graders from two junior high schools. Total of 1073 valid questionnaires were collected. The self-completed questionnaire included background information, smoking status of relatives staying with the subject, attitudes of parents towards child smoking, knowledge and attitudes towards smoking, and anti-smoking self-efficacy. Results and clinical applications: Subjects in the experimental group underwent course interventions, which are 'smoking prevention courses,' in the semester. After course intervention, it was found that the intervention showed significant efficacy in terms of knowledge and self-efficacy in rejecting smoking in senior high school students but no efficacy in junior high school. We recommend that this course can be used in normal senior high schools. With regards to junior high schools, smoking prevention courses should be designed to be gamified, or combined with activities with both anti-smoking messages and entertainment at the same time, so that knowledge, attitudes, and self-efficacy can be subconsciously cultivated.

Keywords: adolescent students, smoking knowledge, attitudes, anti-smoking self-efficiency, smoking prevention intervention

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13558 Performance and Voyage Analysis of Marine Gas Turbine Engine, Installed to Power and Propel an Ocean-Going Cruise Ship from Lagos to Jeddah

Authors: Mathias U. Bonet, Pericles Pilidis, Georgios Doulgeris

Abstract:

An aero-derivative marine Gas Turbine engine model is simulated to be installed as the main propulsion prime mover to power a cruise ship which is designed and routed to transport intending Muslim pilgrims for the annual hajj pilgrimage from Nigeria to the Islamic port city of Jeddah in Saudi Arabia. A performance assessment of the Gas Turbine engine has been conducted by examining the effect of varying aerodynamic and hydrodynamic conditions encountered at various geographical locations along the scheduled transit route during the voyage. The investigation focuses on the overall behavior of the Gas Turbine engine employed to power and propel the ship as it operates under ideal and adverse conditions to be encountered during calm and rough weather according to the different seasons of the year under which the voyage may be undertaken. The variation of engine performance under varying operating conditions has been considered as a very important economic issue by determining the time the speed by which the journey is completed as well as the quantity of fuel required for undertaking the voyage. The assessment also focuses on the increased resistance caused by the fouling of the submerged portion of the ship hull surface with its resultant effect on the power output of the engine as well as the overall performance of the propulsion system. Daily ambient temperature levels were obtained by accessing data from the UK Meteorological Office while the varying degree of turbulence along the transit route and according to the Beaufort scale were also obtained as major input variables of the investigation. By assuming the ship to be navigating the Atlantic Ocean and the Mediterranean Sea during winter, spring and summer seasons, the performance modeling and simulation was accomplished through the use of an integrated Gas Turbine performance simulation code known as ‘Turbomach’ along with a Matlab generated code named ‘Poseidon’, all of which have been developed at the Power and Propulsion Department of Cranfield University. As a case study, the results of the various assumptions have further revealed that the marine Gas Turbine is a reliable and available alternative to the conventional marine propulsion prime movers that have dominated the maritime industry before now. The techno-economic and environmental assessment of this type of propulsion prime mover has enabled the determination of the effect of changes in weather and sea conditions on the ship speed as well as trip time and the quantity of fuel required to be burned throughout the voyage.

Keywords: ambient temperature, hull fouling, marine gas turbine, performance, propulsion, voyage

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13557 Comparative Study of Different Enhancement Techniques for Computed Tomography Images

Authors: C. G. Jinimole, A. Harsha

Abstract:

One of the key problems facing in the analysis of Computed Tomography (CT) images is the poor contrast of the images. Image enhancement can be used to improve the visual clarity and quality of the images or to provide a better transformation representation for further processing. Contrast enhancement of images is one of the acceptable methods used for image enhancement in various applications in the medical field. This will be helpful to visualize and extract details of brain infarctions, tumors, and cancers from the CT image. This paper presents a comparison study of five contrast enhancement techniques suitable for the contrast enhancement of CT images. The types of techniques include Power Law Transformation, Logarithmic Transformation, Histogram Equalization, Contrast Stretching, and Laplacian Transformation. All these techniques are compared with each other to find out which enhancement provides better contrast of CT image. For the comparison of the techniques, the parameters Peak Signal to Noise Ratio (PSNR) and Mean Square Error (MSE) are used. Logarithmic Transformation provided the clearer and best quality image compared to all other techniques studied and has got the highest value of PSNR. Comparison concludes with better approach for its future research especially for mapping abnormalities from CT images resulting from Brain Injuries.

Keywords: computed tomography, enhancement techniques, increasing contrast, PSNR and MSE

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13556 Influence of Packing Density of Layers Placed in Specific Order in Composite Nonwoven Structure for Improved Filtration Performance

Authors: Saiyed M Ishtiaque, Priyal Dixit

Abstract:

Objectives: An approach is being suggested to design the filter media to maximize the filtration efficiency with minimum possible pressure drop of composite nonwoven by incorporating the layers of different packing densities induced by fibre of different deniers and punching parameters by using the concept of sequential punching technique in specific order in layered composite nonwoven structure. X-ray computed tomography technique is used to measure the packing density along the thickness of layered nonwoven structure composed by placing the layer of differently oriented fibres influenced by fibres of different deniers and punching parameters in various combinations to minimize the pressure drop at maximum possible filtration efficiency. Methodology Used: This work involves preparation of needle punched layered structure with batts 100g/m2 basis weight having fibre denier, punch density and needle penetration depth as variables to produce 300 g/m2 basis weight nonwoven composite. X-ray computed tomography technique is used to measure the packing density along the thickness of layered nonwoven structure composed by placing the layers of differently oriented fibres influenced by considered variables in various combinations. to minimize the pressure drop at maximum possible filtration efficiencyFor developing layered nonwoven fabrics, batts made of fibre of different deniers having 100g/m2 each basis weight were placed in various combinations. For second set of experiment, the composite nonwoven fabrics were prepared by using 3 denier circular cross section polyester fibre having 64 mm length on needle punched nonwoven machine by using the sequential punching technique to prepare the composite nonwoven fabrics. In this technique, three semi punched fabrics of 100 g/m2 each having either different punch densities or needle penetration depths were prepared for first phase of fabric preparation. These fabrics were later punched altogether to obtain the overall basis weight of 300 g/m2. The total punch density of the composite nonwoven fabric was kept at 200 punches/ cm2 with a needle penetration depth of 10 mm. The layered structures so formed were subcategorised into two groups- homogeneous layered structure in which all the three batts comprising the nonwoven fabric were made from same denier of fibre, punch density and needle penetration depth and were placed in different positions in respective fabric and heterogeneous layered structure in which batts were made from fibres of different deniers, punch densities and needle penetration depths and were placed in different positions. Contributions: The results concluded that reduction in pressure drop is not derived by the overall packing density of the layered nonwoven fabric rather sequencing of layers of specific packing density in layered structure decides the pressure drop. Accordingly, creation of inverse gradient of packing density in layered structure provided maximum filtration efficiency with least pressure drop. This study paves the way for the possibility of customising the composite nonwoven fabrics by the incorporation of differently oriented fibres in constituent layers induced by considered variablres for desired filtration properties.

Keywords: filtration efficiency, layered nonwoven structure, packing density, pressure drop

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13555 Annoyance Caused by Air Pollution: A Comparative Study of Two Industrialized Regions

Authors: Milena M. Melo, Jane M. Santos, Severine Frere, Valderio A. Reisen, Neyval C. Reis Jr., Mariade Fátima S. Leite

Abstract:

Although there had been a many studies that shows the impact of air pollution on physical health, comparatively less was known of human behavioral responses and annoyance impacts. Annoyance caused by air pollution is a public health problem because it can be an ambient stressor causing stress and disease and can affect quality of life. The objective of this work is to evaluate the annoyance caused by air pollution in two different industrialized urban areas, Dunkirk (France) and Vitoria (Brazil). The populations of these cities often report feeling annoyed by dust. Surveys were conducted, and the collected data were analyzed using statistical analyses. The results show that sociodemographic variables, importance of air quality, perceived industrial risk, perceived air pollution and occurrence of health problems play important roles in the perceived annoyance. These results show the existence of a common problem in geographically distant areas and allow stakeholders to develop prevention strategies.

Keywords: air pollution, annoyance, industrial risks, public health, perception of pollution, settled dust

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13554 Land Degradation Assessment through Spatial Data Integration in Eastern Chotanagpur Plateau, India

Authors: Avijit Mahala

Abstract:

Present study is primarily concerned with the physical processes and status of land degradation in a tropical plateau fringe. Chotanagpur plateau is one of the most water erosion related degraded areas of India. The granite gneiss geological formation, low to medium developed soil cover, undulating lateritic uplands, high drainage density, low to medium rainfall (100-140cm), dry tropical deciduous forest cover makes the Silabati River basin a truly representative of the tropical environment. The different physical factors have been taken for land degradation study includes- physiographic formations, hydrologic characteristics, and vegetation cover. Water erosion, vegetal degradation, soil quality decline are the major processes of land degradation in study area. Granite-gneiss geological formation is responsible for developing undulating landforms. Less developed soil profile, low organic matter, poor structure of soil causes high soil erosion. High relief and sloppy areas cause unstable environment. The dissected highland causes topographic hindrance in productivity. High drainage density and frequency in rugged upland and intense erosion in sloppy areas causes high soil erosion of the basin. Decreasing rainfall and increasing aridity (low P/PET) threats water stress condition. Green biomass cover area is also continuously declining. Through overlaying the different physical factors (geological formation, soil characteristics, geomorphological characteristics, etc.) of considerable importance in GIS environment the varying intensities of land degradation areas has been identified. Middle reaches of Silabati basin with highly eroded laterite soil cover areas are more prone to land degradation.

Keywords: land degradation, tropical environment, lateritic upland, undulating landform, aridity, GIS environment

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13553 Tax Avoidance During The Financial Crisis: Role Of Independent Commissioners And External Auditors

Authors: Yasir Ramadhan

Abstract:

This study aims to investigate tax avoidance practices when a financial crisis occurs due to the effects of the COVID-19 pandemic. This study also finds out how the influence of independent commissioners and external auditors on tax avoidance practices during the COVID-19 pandemic. Tax avoidance practices are measured by the current ETR. The role of the independent board of commissioners is measured by the proportion of independent commissioners in the composition of the board of commissioners, while the external auditor is measured by audit quality. In this study, there were 342 observations of companies listed on the Indonesia Stock Exchange from 2019 to 2020. This study used the difference-in-differences (DiD) method in data analysis. The results of this study indicate that companies do tax avoidance during the COVID-19 pandemic. Meanwhile, independent commissioners and qualified audits are not proven to be able to negate tax avoidance practices during the COVID-19 Pandemic. These results also show that a higher proportion of independent commissioners and audit quality are not sufficient for countries with low levels of auditor litigation and investor protection and weak regulatory frameworks.

Keywords: audit, commissioner, tax avoidance, COVID-19 pandemic

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13552 Thermo-Economic Analysis of a Natural Draft Direct Cooling System for a Molten Salt Power Tower

Authors: Huiqiang Yang, Domingo Santana

Abstract:

Reducing parasitic power consumption of concentrating solar power plants is the main challenge to increase the overall efficiency, particularly for molten salt tower technology. One of the most effective approaches to reduce the parasitic power consumption is to implement a natural draft dry cooling system instead of the standard utilized mechanical draft dry cooling system. In this paper, a thermo-economic analysis of a natural draft direct cooling system was performed based on a 100MWe commercial scale molten salt power plant. In this configuration with a natural draft direct cooling system, the exhaust steam from steam turbine flows directly to the heat exchanger bundles inside the natural draft dry cooling tower, which eliminates the power consumption of circulation pumps or fans, although the cooling tower shadows a portion of the heliostat field. The simulation results also show that compared to a mechanical draft cooling system the annual solar field efficiency is decreased by about 0.2% due to the shadow, which is equal to a reduction of approximately 13% of the solar field area. As a contrast, reducing the solar field size by 13% in purpose in a molten salt power plant with a natural draft drying cooling system actually will lead to a reduction of levelized cost of electricity (LCOE) by about 4.06% without interfering the power generated.

Keywords: molten salt power tower, natural draft dry cooling, parasitic power consumption, commercial scale

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13551 Economic Assessment of CO2-Based Methane, Methanol and Polyoxymethylene Production

Authors: Wieland Hoppe, Nadine Wachter, Stefan Bringezu

Abstract:

Carbon dioxide (CO2) utilization might be a promising way to substitute fossil raw materials like coal, oil or natural gas as carbon source of chemical production. While first life cycle assessments indicate a positive environmental performance of CO2-based process routes, a commercialization of CO2 is limited by several economic obstacles up to now. We, therefore, analyzed the economic performance of the three CO2-based chemicals methane and methanol as basic chemicals and polyoxymethylene as polymer on a cradle-to-gate basis. Our approach is oriented towards life cycle costing. The focus lies on the cost drivers of CO2-based technologies and options to stimulate a CO2-based economy by changing regulative factors. In this way, we analyze various modes of operation and give an outlook for the potentially cost-effective development in the next decades. Biogas, waste gases of a cement plant, and flue gases of a waste incineration plant are considered as CO2-sources. The energy needed to convert CO2 into hydrocarbons via electrolysis is assumed to be supplied by wind power, which is increasingly available in Germany. Economic data originates from both industrial processes and process simulations. The results indicate that CO2-based production technologies are not competitive with conventional production methods under present conditions. This is mainly due to high electricity generation costs and regulative factors like the German Renewable Energy Act (EEG). While the decrease in production costs of CO2-based chemicals might be limited in the next decades, a modification of relevant regulative factors could potentially promote an earlier commercialization.

Keywords: carbon capture and utilization (CCU), economic assessment, life cycle costing (LCC), power-to-X

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13550 Degradation of Amitriptyline Hydrochloride, Methyl Salicylate and 2-Phenoxyethanol in Water Systems by the Combination UV/Cl2

Authors: F. Javier Benitez, Francisco J. Real, Juan Luis Acero, Francisco Casas

Abstract:

Three emerging contaminants (amitriptyline hydrochloride, methyl salicylate and 2-phenoxyethanol) frequently found in waste-waters were selected to be individually degraded in ultra-pure water by the combined advanced oxidation process constituted by UV radiation and chlorine. The influence of pH, initial chlorine concentration and nature of the contaminants was firstly explored. The trend for the reactivity of the selected compounds was deduced: amitriptyline hydrochloride > methyl salicylate > 2-phenoxyethanol. A later kinetic study was carried out and focused on the specific evaluation of the first-order rate constants and the determination of the partial contribution to the global reaction of the direct photochemical pathway and the radical pathway. A comparison between the rate constant values among photochemical experiments without and with the presence of Cl2 reveals a clear increase in the oxidation efficiency of the combined process with respect to the photochemical reaction alone. In a second stage, the simultaneous oxidation of mixtures of the selected contaminants in several types of water (ultrapure water, surface water from a reservoir, and two secondary effluents) was also performed by the same combination UV/Cl2 under more realistic operating conditions. The efficiency of this combined system UV/Cl2 was compared to other oxidants such as the UV/S2O82- and UV/H2O2 AOPs. Results confirmed that the UV/Cl2 system provides higher elimination efficiencies among the AOPs tested.

Keywords: emerging contaminants, UV/chlorine advanced oxidation process, amitriptyline, methyl salicylate, 2-phenoxyethanol, chlorination, photolysis

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13549 Bioefficiency of Cinnamomum verum Loaded Niosomes and Its Microbicidal and Mosquito Larvicidal Activity against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus

Authors: Aasaithambi Kalaiselvi, Michael Gabriel Paulraj, Ekambaram Nakkeeran

Abstract:

Emergences of mosquito vector-borne diseases are considered as a perpetual problem globally in tropical countries. The outbreak of several diseases such as chikungunya, zika virus infection and dengue fever has created a massive threat towards the living population. Frequent usage of synthetic insecticides like Dichloro Diphenyl Trichloroethane (DDT) eventually had its adverse harmful effects on humans as well as the environment. Since there are no perennial vaccines, prevention, treatment or drugs available for these pathogenic vectors, WHO is more concerned in eradicating their breeding sites effectively without any side effects on humans and environment by approaching plant-derived natural eco-friendly bio-insecticides. The aim of this study is to investigate the larvicidal potency of Cinnamomum verum essential oil (CEO) loaded niosomes. Cholesterol and surfactant variants of Span 20, 60 and 80 were used in synthesizing CEO loaded niosomes using Transmembrane pH gradient method. The synthesized CEO loaded niosomes were characterized by Zeta potential, particle size, Fourier Transform Infrared Spectroscopy (FT-IR), GC-MS and SEM analysis to evaluate charge, size, functional properties, the composition of secondary metabolites and morphology. The Z-average size of the formed niosomes was 1870.84 nm and had good stability with zeta potential -85.3 meV. The entrapment efficiency of the CEO loaded niosomes was determined by UV-Visible Spectrophotometry. The bio-potency of CEO loaded niosomes was treated and assessed against gram-positive (Bacillus subtilis) and gram-negative (Escherichia coli) bacteria and fungi (Aspergillus fumigatus and Candida albicans) at various concentrations. The larvicidal activity was evaluated against II to IV instar larvae of Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus at various concentrations for 24 h. The mortality rate of LC₅₀ and LC₉₀ values were calculated. The results exhibited that CEO loaded niosomes have greater efficiency against mosquito larvicidal activity. The results suggest that niosomes could be used in various applications of biotechnology and drug delivery systems with greater stability by altering the drug of interest.

Keywords: Cinnamomum verum, niosomes, entrapment efficiency, bactericidal and fungicidal, mosquito larvicidal activity

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13548 CuIn₃Se₅ Colloidal Nanocrystals and Its Ink-Coated Films for Photovoltaics

Authors: M. Ghali, M. Elnimr, G. F. Ali, A. M. Eissa, H. Talaat

Abstract:

CuIn₃Se₅ material is indexed as ordered vacancy compounds having excellent matching properties with CuInGaSe (CIGS) solar absorber layer. For example, the valence band offset of CuIn₃Se₅ with CIGS is nearly 0.3 eV, and the lattice mismatch is less than 1%, besides the absence of discontinuity in their conduction bands. Thus, CuIn₃Se₅ can work as a passivation layer for repelling holes from CIGS/CdS interface and hence to reduce the interface carriers recombination and consequently enhancing the efficiency of CIGS/CdS solar cells. Theoretically, it was reported earlier that an improvement in the efficiency of p-CIGS-based solar cell with a thin ~100 nm of n-CuIn₃Se₅ layer is expected. Recently, a reported experiment demonstrated significant improvement in the efficiency of Molecular Beam Epitaxy (MBE) grown CIGS solar cells from 13.4 to 14.5% via inserting a thin layer of MBE-grown Cu(In,Ga)₃Se₅ layer at the CdS/CIGS interface. It should be mentioned that CuIn₃Se₅ material in either bulk or thin film form, are usually fabricated by high vacuum physical vapor deposition techniques (e.g., three-source co-evaporation, RF sputtering, flash evaporation, and molecular beam epitaxy). In addition, achieving photosensitive films of n-CuIn₃Se₅ material is important for new hybrid organic/inorganic structures, where inorganic photo-absorber layer, with n-type conductivity, can form n–p junction with organic p-type material (e.g., conductive polymers). A detailed study of the physical properties of CuIn₃Se₅ is still necessary for better understanding of device operation and further improvement of solar cells performance. Here, we report on the low-cost synthesis of CuIn₃Se₅ material in nano-scale size, with an average diameter ~10nm, using simple solution-based colloidal chemistry. In contrast to traditionally grown bulk tetragonal CuIn₃Se₅ crystals using high Vacuum-based technology, our colloidal CuIn₃Se₅ nanocrystals show cubic crystal structure with a shape of nanoparticles and band gap ~1.33 eV. Ink-coated thin films prepared from these nanocrystals colloids; display n-type character, 1.26 eV band gap and strong photo-responsive behavior with incident white light. This suggests the potential use of colloidal CuIn₃Se₅ as an active layer in all-solution-processed thin film solar cells.

Keywords: nanocrystals, CuInSe, thin film, optical properties

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