Search results for: board and audit committee characteristics
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8726

Search results for: board and audit committee characteristics

6626 Towards an African Model: A Survey of Social Enterprises in South Africa

Authors: Kerryn Krige, Kerrin Myers

Abstract:

Social entrepreneurship offers the opportunity to simultaneously address both social and economic inequality in South Africa. Its appeal across racial groups, its attractiveness to young people, its applicability in rural and peri-urban markets, and its acceleration in middle income, large-business economies suits the South African context. However, the potential to deliver much-needed developmental benefits has not been realised because the social entrepreneurship debate lacks evidence as to who social entrepreneurs are, their goals and operations and the socio-economic results they achieve. As a result, policy development has been stunted, and legislative barriers and red tape remain. Social entrepreneurs are isolated from the mainstream economy, and struggle to access funding because of limitations in legislative and organisational structures. The objective of the study is to strengthen the ecosystem for social entrepreneurship in South Africa by producing robust, policy-rich information from and about social enterprises currently in operation across the country. The study employs a quantitative survey methodology, using online and telephonic data collection methods. A purposive sample of 1000 social enterprises was included in the first large-scale study of social entrepreneurship in South Africa. The results offer deep insight into the characteristics of social enterprises; the activities they undertake and the markets they serve; their modes of operation and funding sources as well as key challenges and support systems. The results contribute towards developing a model of social enterprise in the African context.

Keywords: social enterprise, key characteristics, challenges and enablers, towards an African model

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6625 Analysis of Determinants of Growth of Small and Medium Enterprises in Kwara State, Nigeria

Authors: Hussaini Tunde Subairu

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Small and Medium Enterprises (SMEs) sectors serve as catalyst for employment generation, national growth, poverty reduction and economic development in developing and developed countries. However, in Nigeria despite copious and plethora of government policies and stimulus schemes directed at SMEs, the sector is still characterized by high rate of failure and discontinuities. This study therefore investigated owners/managers profile, firms characteristics and external factors as possible determinants of SMEs growth from selected SMEs in Kwara State. Primary data were sourced from 200 SMEs respondents registered with the National Association of Small and Medium Enterprises (NASMES) in Kwara State Central Senatorial District. Multiple Regressions Analysis (MRA) was used to analyze the relationship between dependent and independent variables, and pair wise correlation was employed to examine the relationship among independent variables. The Analysis of Variable (ANOVA) was employed to indicate the overall significant of the model The findings revealed that Analysis of variance (ANOVA) put the value of F-statistics at 420.45 and p-value at 0.000 was significant. The values of R2 and Adjusted R2 of 0.9643 and 0.9620 respectively suggested that 96 percent of variations in employment growth were explained by the explanatory variables. The level of technical and managerial education has t- value of 24.14 and p-value of 0.001, length of managers/owners experience in similar trade with t- value of 21.37 and p-value of 0.001, age of managers/owners with t- value of 42.98 and p-value of 0.001, firm age with t- value of 25.91 and p-value of 0.001, numbers of firms in a cluster with t- value of 7.20 and p-value of 0.001, access to formal finance with t-value of 5.56 and p-value of 0.001, firm technology innovation with t- value of 25.32 and p-value of 0.01, institutional support with t- value of 18.89 and p-value of 0.01, globalization with t- value of 9.78 and p-value of 0.01, and infrastructure with t-value of 10.75 and p-value of 0.01. The result also indicated that initial size has t-value of -1.71 and p-value of 0.090 which is consistent with Gibrat’s Law. The study concluded that owners/managers profile, firm specific characteristics and external factors substantially influenced employment growths of SMEs in the study area. Therefore, policy implication should enhance human capital development of SMEs owners/managers, and strengthen fiscal policy thrust through imposition on tariff regime to minimize effect of globalization. Governments at all level must support SMEs growth radically and enhance institutional support for SMEs growth and radically and significantly upgrading key infrastructure as rail/roads, rail, telecommunications, water and power.

Keywords: external factors, firm specific characteristics, owners / manager profile, small and medium enterprises

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6624 Modification of Electrical and Switching Characteristics of a Non Punch-Through Insulated Gate Bipolar Transistor by Gamma Irradiation

Authors: Hani Baek, Gwang Min Sun, Chansun Shin, Sung Ho Ahn

Abstract:

Fast neutron irradiation using nuclear reactors is an effective method to improve switching loss and short circuit durability of power semiconductor (insulated gate bipolar transistors (IGBT) and insulated gate transistors (IGT), etc.). However, not only fast neutrons but also thermal neutrons, epithermal neutrons and gamma exist in the nuclear reactor. And the electrical properties of the IGBT may be deteriorated by the irradiation of gamma. Gamma irradiation damages are known to be caused by Total Ionizing Dose (TID) effect and Single Event Effect (SEE), Displacement Damage. Especially, the TID effect deteriorated the electrical properties such as leakage current and threshold voltage of a power semiconductor. This work can confirm the effect of the gamma irradiation on the electrical properties of 600 V NPT-IGBT. Irradiation of gamma forms lattice defects in the gate oxide and Si-SiO2 interface of the IGBT. It was confirmed that this lattice defect acts on the center of the trap and affects the threshold voltage, thereby negatively shifted the threshold voltage according to TID. In addition to the change in the carrier mobility, the conductivity modulation decreases in the n-drift region, indicating a negative influence that the forward voltage drop decreases. The turn-off delay time of the device before irradiation was 212 ns. Those of 2.5, 10, 30, 70 and 100 kRad(Si) were 225, 258, 311, 328, and 350 ns, respectively. The gamma irradiation increased the turn-off delay time of the IGBT by approximately 65%, and the switching characteristics deteriorated.

Keywords: NPT-IGBT, gamma irradiation, switching, turn-off delay time, recombination, trap center

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6623 The Restrictions of the Householder’s ‘Double Two-Thirds Principles’ in Decision-Making for Elevators Addition to Existing Condominium

Authors: Haifeng Shi, Kun Song, Yili Zhao

Abstract:

In China, with the extensive promotion of the ‘aging in place’ pension policy as the background, most of the elders will choose to remain in their current homes and communities, finding out of preference or necessity that they will need to remodel their homes to fit their changing needs. This generation elder born in the 1960s to 1970s almost live in the same form of housing-condominium built from 1982 to 2012. Based on the survey of existing multi-family housing, especially in Tianjin, it is found that the current ‘double two-thirds principles’ is becoming the threshold for modification to existing house, particularly in the project of elevators addition to existing condominium (built from 1982 to 2016 without elevators below 6 floors according to the previous building code). Firstly, this article concludes the local policies of elevator addition nationwide, most of which has determined the importance and necessity of the community-based self-organization principle in the operation of the elevator addition. Secondly, by comparing the three existing community management systems (owners' congress, property management system and community committee) in instances, find that the community-based ‘two-thirds’ principle is not conducive to implement for multi-owned property renovation in the community or common accessibility modification in the building. However, analysis the property and other community management related laws, pointing out the shortcomings of the existing community-based ‘two-thirds’ decision-making norms. The analyzation showed that the unit-based and ‘100% principle’ method is more capable of common accessibility in the condominium in China. Differing from existing laws, the unit-based principle will be effective for the process of decision-making and ‘100% principle’ will protect closely profit-related householders for condominium modification in the multi-owned area. These three aspects of the analysis suggest that the establishment of the unit-based self-organization mechanism is a preferred and inevitable method to solve the problem of elevators addition to the existing condominium in China.

Keywords: aging in place, condominium, modification, multi own

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6622 An Appraisal of Grade 12 Educators’ Difficulties in Understanding Electric Circuits in South Africa: A Case Study of Umgungundlovu District of Kwazulu-Natal

Authors: Akinrogunde Omolere Moses

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A plethora of studies indicated that teaching and learning of the physical sciences in the Further Education and Training (FET) Phase (Grades 10–12) have long been declared problematic in South Africa. For instance, the results from the National Senior Certificate Matric Examination in Physical Sciences, especially in the questions related to practical skills, more specifically, electric circuits, have been unsatisfactory in the past decades. Learner difficulties in understanding electric circuits are well stated. Thus, this study appraised the difficulties Grade 12 Educators often face in understanding Electric Circuits in Umgungundlovu, District of Kwazulu-Natal, South Africa. A mixed-methods research methodology was employed, while a total of 30 schools were sampled, including Ex-Model C, Independent Exam Board, community, rural, and deep rural schools. Data were collected through semi-structured questionnaires. The findings revealed that a large percentage of the Grade 12 physical sciences educators have difficulties with the Grade 9 and 12 physical sciences content. It was also observed that most of the educators who had difficulties were unable to detect the type of difficulties learners would experience; as a result, they were unable to explain why learners experience such difficulties. The results also showed that only those educators with more experience in teaching the physical sciences were able to provide clearer explanations of both the why and how of dealing with learner difficulties with this section on electric circuits. The study recommended that there is a need to recruit more qualified educators, with at least a Bachelor of Science in Physics in particular, in order to combat the misconceptions. Also, Educators with an inadequate understanding of physical sciences should be orientated in order to meet the standard of classroom practice.

Keywords: grade 12 educators' difficulties, electric circuits, learners' difficulties, educators understanding of EC.

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6621 Hydrogeochemistry Preliminary Study of Groundwater Conservation in Buton Island, Southeast Sulawesi, Indonesia

Authors: M. S. M. Prahastomi, Riki Sunaryo, Lorasa Ximanes

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The research takes place in EP Area, in the Northern part of Buton, Southeast Sulawesi Province, Indonesia. It is one example of karst areas that have good water resources potential. The landscape is in the form of valleys and hills which is good enough for recharge zone and discharge zones of groundwater. However, the geological characteristics of karst dissolution and a complex geological structure are quite influential to the groundwater flow system in the region. The Discharge of groundwater to the surface can be caused by a fracture in the rock, Underground River due to dissolution, and the contact between permeable rocks with impermeable rocks. In the concept of hydrogeology, groundwater is one of the components of the hydrological cycle which is closely linked to the availability of water under the surface, precipitation, infiltration, percolation, evapotranspiration, and surface runoff. Conceptually, the condition of recharge and discharge areas can be identified through a research distribution springs in a region. The understanding of the condition and the nature of the potential catchment area of groundwater flow, mainly from the catchment area to the discharge area, is urgently needed. This research aimed to assess the general geological conditions of the study area, which is expected to provide an overview of groundwater flow events that used by the public as well as industry. Behavioral characteristics of groundwater become an integral part in the search for potential groundwater in the study area. As for the research methods used hydrogeology mapping and laboratory works.

Keywords: Buton Island, groundwater conservation, hydrogeochemistry preliminary, karst

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6620 The Analgesic Impact of Adding Intrathecal Ketamine to Spinal Anaesthesia for Hip or Knee Arthroplasty: A Clinical Audit

Authors: Carl Ashworth, Matthys Campher

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Spinal anaesthesia has been identified as the “gold standard” for primary elective total hip and knee arthroplasty, which is most commonly performed using longer-acting local anaesthetics, such as hyperbaric bupivacaine, to prolong the duration of anaesthesia and analgesia suitable for these procedures. Ketamine is known to have local anaesthetic effects with potent analgesic properties and has been evaluated as a sole anaesthetic agent via intrathecal administration; however, the use of intrathecal ketamine as an adjunct to intrathecal hyperbaric bupivacaine, morphine, and fentanyl has not been extensively studied. The objective of this study was to identify the potential analgesic effects of the addition of intrathecal ketamine to spinal anaesthesia and to compare the efficacy and safety of adding intrathecal ketamine to spinal anaesthesia for hip- or knee arthroplasty with spinal anaesthesia for hip- or knee arthroplasty without intrathecal ketamine. The medical records of patients who underwent elective hip- or knee arthroplasty under spinal anaesthesia performed by an individual anaesthetist with either intrathecal hyperbaric bupivacaine, morphine and fentanyl or intrathecal hyperbaric bupivacaine, morphine, fentanyl and ketamine between June 4, 2020, and June 4, 2022, were retrospectively reviewed. These encounters were reviewed and analyzed from a perioperative pain perspective, with the primary outcome measure as the oral morphine equivalent (OME) usage in the 48 hours post-spinal anaesthesia, and secondary outcome measures including time to breakthrough analgesia, self-reported pain scores at rest and during movement at 24 and 48 hours after surgery, adverse effects of analgesia, complications, and length of stay. There were 26 patients identified who underwent TKR between June 4, 2020, and June 4, 2022, and 25 patients who underwent THR with the same conditions. It was identified that patients who underwent traditional spinal anaesthesia with the addition of ketamine for elective hip- or knee arthroplasty had a lower mean total OME in the 48 hours immediately post-spinal anaesthesia yet had a shorter time to breakthrough analgesia administration. The proposed mechanism of action for intrathecal ketamine as an additive to traditional spinal anaesthesia for elective hip- or knee arthroplasty is that it may prolong and attenuate the analgesic effect of traditional spinal anaesthesia. There were no significant differences identified in comparing the efficacy and safety of adding intrathecal ketamine to spinal anaesthesia for hip- or knee arthroplasty with spinal anaesthesia for hip- or knee arthroplasty without intrathecal ketamine.

Keywords: anaesthesia, spinal, intra-thecal, ketamine, spinal-morphine, bupivacaine

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6619 A Study of Fatigue Life Estimation of a Modular Unmanned Aerial Vehicle by Developing a Structural Health Monitoring System

Authors: Zain Ul Hassan, Muhammad Zain Ul Abadin, Muhammad Zubair Khan

Abstract:

Unmanned aerial vehicles (UAVs) have now become of predominant importance for various operations, and an immense amount of work is going on in this specific category. The structural stability and life of these UAVs is key factor that should be considered while deploying them to different intelligent operations as their failure leads to loss of sensitive real-time data and cost. This paper presents an applied research on the development of a structural health monitoring system for a UAV designed and fabricated by deploying modular approach. Firstly, a modular UAV has been designed which allows to dismantle and to reassemble the components of the UAV without effecting the whole assembly of UAV. This novel approach makes the vehicle very sustainable and decreases its maintenance cost to a significant value by making possible to replace only the part leading to failure. Then the SHM for the designed architecture of the UAV had been specified as a combination of wings integrated with strain gauges, on-board data logger, bridge circuitry and the ground station. For the research purpose sensors have only been attached to the wings being the most load bearing part and as per analysis was done on ANSYS. On the basis of analysis of the load time spectrum obtained by the data logger during flight, fatigue life of the respective component has been predicted using fracture mechanics techniques of Rain Flow Method and Miner’s Rule. Thus allowing us to monitor the health of a specified component time to time aiding to avoid any failure.

Keywords: fracture mechanics, rain flow method, structural health monitoring system, unmanned aerial vehicle

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6618 Self Help Groups among the Ao Nagas : A Case Study of Alongkima of Nagaland, NorthEast India

Authors: Imkongtenla Pongen

Abstract:

Self Help Groups (SGHs) are socio-commercial instruments in addressing urban poverty and strengthening livelihoods. Being a member of Self Help Group helped in mutual exchanges of ideas, develop risk taking behaviour, learns flexibility in planning of a programme, and interpersonal communication within the group. In the present study, an attempt has been made to examine the functions, characteristics and practices of Self Help Groups and its impact on sustainable development among the Ao Nagas of Alongkima, Nagaland, NorthEast India. They are a tribal group and racially belong to the Mongoloid stock and linguistically to the Tibeto-Burman group. They follow endogamous, patriarchal, and patrilineal system. Major characteristics of Self Help groups in this study are found to be team spirit and group cohesiveness. Such groups are found to be geared towards a number of self-sufficiency based business ventures. The problems faced in normal functioning of the groups are unpunctuality and the inability to attend a meeting by all the members .Participation in such groups has increased women’s influence over the economic resources and decision making in the household, improved self-confidence and living standard, capacity building, self- dependent and self-reliant with no educational and entrepreneurial background, generate savings and hone their skills as motivators and leaders. All these has enhanced her status in every sphere of life in par with the opposite gender. In a nutshell, we can say that what she cannot achieve as an individual, she can achieve as a member of a Self Help Group. Hence, we should try to develop mechanisms to guarantee the sustainability of Self Help Groups which depends on the way they can deal with both internal and external conflicts like globalization and competition from new markets.

Keywords: Ao nagas, microfinance, self help group, women empowerment

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6617 Effect of Sodium Chloride Replacement with Potassium Chloride on Qualities of Longan Seasoning Powder

Authors: Narin Charoenphun, Praopen Rattanadee, Chaiporn Phaephiromrat

Abstract:

One of the most important intricacies of cooking is seasoning which is the process of adding salt, herbs, or spices to food to enhance the flavor. Sodium chloride (NaCl) was added in seasoning powder for taste-improving and shelf life of products. However, the raised blood pressure caused by eating too much NaCl may damage the arteries leading to the heart. Interestingly, NaCl replacement with other substance is essential for consumer. The objective of this study was to investigate the effects of NaCl replacement with potassium chloride (KCl) on the sensory characteristics and physiochemical properties of longan seasoning powder. Five longan seasoning Powder were replaced sodium chloride with KCl at 0, 25, 50 75 and 100%. Mixture design with 2 replications was performed. Sensory characteristics on overall flavor, saltiness, sweetness, bitterness and overall liking were investigated using 12 descriptive trained panelists. Results revealed that NaCl and KCl had effects on saltiness, bitterness and overall liking. As the level of KCl substituted increased, the overall flavor and sweetness of powdered seasoning from longan were not significantly (p < 0.05). This resulted in the decrease of overall liking of the products. In addition, increasing the level of KCl substituted resulted in the drop of saltiness but out of bitterness of the products. Saltiness of powdered seasoning from longan with replacement levels of 50, 75 and 100% KCl different when compared to that of 0% KCl. Bitterness of powdered seasoning from longan with replacement levels of 50, 75 and 100% KCl different when compared to that of 0% KCl. Moreover, consumer acceptance test was conducted (n=100). In conclusion, the optimum formulation contained of 32.0% longan powder, 28.0% sugar, 15.0% NaCl, 5% KCl, 16.0% pork powder, 3.0% pepper powder, and 3.0% garlic powder that would meet acceptability scores of at least 7 or like moderately.

Keywords: longan, seasoning, NaCl, KCl

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6616 A Cross-Sectional Evaluation of the Lack of Racial, Sexual, and Gender Diversity among Top Dermatologist Influencers on TikTok

Authors: Madison Meyer

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Dermatological conditions are one of the most viewed medical subjects on the social media platform TikTok, resulting in the rise of several prominent American board-certified dermatologists as influencers. Notably, dermatology is one of the least diverse specialties. This cross-sectional study aimed to assess individuals’ preferences related to race, gender, and sexual identity of doctors in terms of dermatology-related information on TikTok and which group posts more reliable information. This study qualitatively and quantitatively evaluated the racial, gender, and sexual diversity of the top 55 dermatologist influencers on TikTok based on their follower count. The DISCERN tool was used to determine the reliability of consumer health content based on a score ranging from 1-5. Among the top 55 dermatologist influencers, African American (54,241.60) and Latinx (6,696) groups had the lowest mean number of followers compared to Caucasian (1,046,298.50) and Asian (1,403,393.50) physicians. Latinx and African American dermatologists had the highest DISCERN scores of 2 and 1.9, respectively. None of the physicians identified as a different gender or as LGBTQIA+ in any racial category. There is a considerable lack of minority dermatologist influencers on TikTok, especially Latinx, African American, and LGBTQIA+ physicians. The lack of diversity in the dermatology specialty can lead to inequitable care and health outcomes for racial/ethnic, gender, and sexual minority patient populations. This study’s findings also suggest Latinx and African American dermatologists post more reliable content compared with their Caucasian and Asian counterparts.

Keywords: dermatology, social media, sexual and gender minorities, racial minorities, skin of color, tiktok

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6615 Vibration Transmission across Junctions of Walls and Floors in an Apartment Building: An Experimental Investigation

Authors: Hugo Sampaio Libero, Max de Castro Magalhaes

Abstract:

The perception of sound radiated from a building floor is greatly influenced by the rooms in which it is immersed and by the position of both listener and source. The main question that remains unanswered is related to the influence of the source position on the sound power radiated by a complex wall-floor system in buildings. This research is concerned with the investigation of vibration transmission across walls and floors in buildings. It is primarily based on the determination of vibration reduction index via experimental tests. Knowledge of this parameter may help in predicting noise and vibration propagation in building components. First, the physical mechanisms involving vibration transmission across structural junctions are described. An experimental setup is performed to aid this investigation. The experimental tests have shown that the vibration generation in the walls and floors is directed related to their size and boundary conditions. It is also shown that the vibration source position can affect the overall vibration spectrum significantly. Second, the characteristics of the noise spectra inside the rooms due to an impact source (tapping machine) are also presented. Conclusions are drawn for the general trend of vibration and noise spectrum of the structural components and rooms, respectively. In summary, the aim of this paper is to investigate the vibro-acoustical behavior of building floors and walls under floor impact excitation. The impact excitation was at distinct positions on the slab. The analysis has highlighted the main physical characteristics of the vibration transmission mechanism.

Keywords: vibration transmission, vibration reduction index, impact excitation, experimental tests

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6614 Livestock Depredation by Large Predators: Patterns, Perceptions and Implications for Conservation and Livelihoods in Karakoram Mountain Ranges

Authors: Muhammad Zafar Khan, Babar Khan, Muhammad Saeed Awan, Farida Begum

Abstract:

Livestock depredation has greater significance in pastoral societies like Himalaya-Karakoram-Hindu Kush mountain ranges. The dynamics of depredation by large predators (snow leopard and wolf) and its implications for conservation and livelihoods of local people was investigated by household surveys in Hushey valley of Central Karakoram National Park, Pakistan. We found that, during five years (2008-12) 90% of the households in the valley had lost their livestock to snow leopard and wolf, accounting for 4.3% of the total livestock holding per year. On average each household had to bear a loss of 0.8 livestock head per year, equivalent to Pak Rupees 9,853 (US$ 101), or 10% of the average annual cash income. Majority of the predation incidences occurred during late summer in alpine pastures, mostly at night when animals were not penned properly. The prey animals in most of the cases were females or young ones. Of the total predation incidences, 60% were attributed to snow leopard, 37% to wolf, while in 3% the predator was unknown. The fear of snow leopard is greater than that of wolf. As immediate response on predation, majority of the local people (64%, n=99) preferred to report the case to their village conservation committee, 32% had no response while only 1% tended to kill the predator. The perceived causes of predation were: poor guarding practices (77%); reduction in wild prey (13%) and livestock being the favourite food of predators (10%). The most preferred strategies for predator management, according to the respondents were improved and enhanced guarding of livestock (72%), followed by increasing wild prey (18%) and lethal control (10%). To strike a balance between predator populations and pastoral livelihoods, better animal husbandry practices should be promoted including: improved guarding through collective hiring of skilled shepherds; corral improvement and use of guard dogs.

Keywords: Panthera unica, Canis lupus, Karakoram, human-carnivore conflict, predation

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6613 Cryogenic Grinding of Mango (Mangifera indica L.) Peel and Its Effect on Chemical and Morphological Characteristics

Authors: Bhupinder Kaur, P. P. Srivastav

Abstract:

The fruit and vegetable industries are responsible for producing huge amount of waste, which is a problem to environmental safety and should be utilized efficiently. Mango (Mangifera indica L.) is an important commercially grown fruit and referred as the “King of fruits”. In 2015, India was the largest producer (18.506 MT) of mangoes and out of which 9.16 % lost during post-harvest handling. The mango kernel and peel represent approximately 17-22% and 7-22% of the overall mass of fruit respectively and discarded as waste. Hence, an attempt has been made with three mango cultivars (Langra, Dashehari, Fazli) to investigate the effect of cryogenic grinding on various characteristics of mango peel powder (MPP). The cryogenic grinding is an emerging technology which is used for retention of beneficial volatile and bioactive components. The feed rate was highest for Langra followed by Chausa. The samples have 2-4% fat along with significant amount of protein (4-6%) and crude fiber (9-13%). Mango peel is also a good source of minerals such as calcium, potassium, manganese, iron, copper, zinc, and magnesium. Interestingly, the significant amount of essential minerals like phosphorus and chlorine in all the varieties was found with the highest value in Langra (phosphorus 10.83% and chlorine 2.41%) which are not reported earlier. SEM analysis revealed the surface morphology and shape of the particles. Waste utilization is a promising measure from both an environmental and economic point of view. Chemical characterization of the samples indicated its potential to be used for the fortification of food products which in turn reduces hazards due to waste and improve functional quality of the foods.

Keywords: cryogenic grinding, morphological, mineral composition, SEM

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6612 Gender and Geographical Disparity in Editorial Boards of Lithuanian Scientific Journals: An Overview of Different Science Disciplines

Authors: Andrius Suminas

Abstract:

Editors-in-chief and members of editorial boards of scientific journals play an extremely important role in the development of science and assure research integrity, as scientific publications are the major results of research. While gender parity in tenure-track hiring decisions and promotion rates has improved, female academics remain underrepresented in senior career phases, including editors-in-chief and members of editorial boards positions of scientific journals. Journal editors and members of editorial boards exert considerable power over what is published and in certain cases the direction of an academic discipline and the career advancement of authors. For this reason it is important to minimize biases extrinsic to the merit of the work impacting publication decisions. One way to achieve this is to ensure a diverse pool of editors and members of editorial boards, ensuring the widest possible coverage of different competencies. This is in line with a diversity model of editorial appointment where editorial boards are structured to dismantle wider conditions of inequality. Another possible option, a distributive model would seek an editorial board reflective of existing proportions in the field at large. Paper presents comprehensive results of Lithuanian scientific journals study. During the research process were reviewed publicly available information from all scientific journals published in Lithuania to infer the proportions of members of editorial boards by gender and country of affiliation. The results of the study revealed differences the proportions of male and female members of editorial boards in different disciplines of science, as well as clear geographical disparity in Lithianian scientific journals editorial boards.

Keywords: scientific journals, editorial boards of scientific journals, gender disparity, geographical disparity, scientific communication

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6611 A Low Order Thermal Envelope Model for Heat Transfer Characteristics of Low-Rise Residential Buildings

Authors: Nadish Anand, Richard D. Gould

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A simplistic model is introduced for determining the thermal characteristics of a Low-rise Residential (LRR) building and then predicts the energy usage by its Heating Ventilation & Air Conditioning (HVAC) system according to changes in weather conditions which are reflected in the Ambient Temperature (Outside Air Temperature). The LRR buildings are treated as a simple lump for solving the heat transfer problem and the model is derived using the lumped capacitance model of transient conduction heat transfer from bodies. Since most contemporary HVAC systems have a thermostat control which will have an offset temperature and user defined set point temperatures which define when the HVAC system will switch on and off. The aim is to predict without any error the Body Temperature (i.e. the Inside Air Temperature) which will estimate the switching on and off of the HVAC system. To validate the mathematical model derived from lumped capacitance we have used EnergyPlus simulation engine, which simulates Buildings with considerable accuracy. We have predicted through the low order model the Inside Air Temperature of a single house kept in three different climate zones (Detroit, Raleigh & Austin) and different orientations for summer and winter seasons. The prediction error from the model for the same day as that of model parameter calculation has showed an error of < 10% in winter for almost all the orientations and climate zones. Whereas the prediction error is only <10% for all the orientations in the summer season for climate zone at higher latitudes (Raleigh & Detroit). Possible factors responsible for the large variations are also noted in the work, paving way for future research.

Keywords: building energy, energy consumption, energy+, HVAC, low order model, lumped capacitance

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6610 Fostering Creativity in Education Exploring Leadership Perspectives on Systemic Barriers to Innovative Pedagogy

Authors: David Crighton, Kelly Smith

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The ability to adopt creative pedagogical approaches is increasingly vital in today’s educational landscape. This study examines the institutional barriers that hinder educators, in the UK, from embracing such innovation, focusing specifically on the experiences and perspectives of educational leaders. Current literature primarily focuses on the challenges that academics and teachers encounter, particularly highlighting how management culture and audit processes negatively affect their ability to be creative in classrooms and lecture theatres. However, this focus leaves a gap in understanding management perspectives, which is crucial for providing a more holistic insight into the challenges encountered in educational settings. To explore this gap, we are conducting semi-structured interviews with senior leaders across various educational contexts, including universities, schools, and further education colleges. This qualitative methodology, combined with thematic analysis, aims to uncover the managerial, financial, and administrative pressures these leaders face in fostering creativity in teaching and supporting professional learning opportunities. Preliminary insights indicate that educational leaders face significant barriers, such as institutional policies, resource limitations, and external performance indicators. These challenges create a restrictive environment that stifles educators' creativity and innovation. Addressing these barriers is essential for empowering staff to adopt more creative pedagogical approaches, ultimately enhancing student engagement and learning outcomes. By alleviating these constraints, educational leaders can cultivate a culture that fosters creativity and flexibility in the classroom. These insights will inform practical recommendations to support institutional change and enhance professional learning opportunities, contributing to a more dynamic educational environment. In conclusion, this study offers a timely exploration of how leadership can influence the pedagogical landscape in a rapidly evolving educational context. The research seeks to highlight the crucial role that educational leaders play in shaping a culture of creativity and adaptability, ensuring that institutions are better equipped to respond to the challenges of contemporary education.

Keywords: educational leadership, professional learning, creative pedagogy, marketisation

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6609 Numerical Study on the Flow around a Steadily Rotating Spring: Understanding the Propulsion of a Bacterial Flagellum

Authors: Won Yeol Choi, Sangmo Kang

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The propulsion of a bacterial flagellum in a viscous fluid has attracted many interests in the field of biological hydrodynamics, but remains yet fully understood and thus still a challenging problem. In this study, therefore, we have numerically investigated the flow around a steadily rotating micro-sized spring to further understand such bacterial flagellum propulsion. Note that a bacterium gains thrust (propulsive force) by rotating the flagellum connected to the body through a bio motor to move forward. For the investigation, we convert the spring model from the micro scale to the macro scale using a similitude law (scale law) and perform simulations on the converted macro-scale model using a commercial software package, CFX v13 (ANSYS). To scrutinize the propulsion characteristics of the flagellum through the simulations, we make parameter studies by changing some flow parameters, such as the pitch, helical radius and rotational speed of the spring and the Reynolds number (or fluid viscosity), expected to affect the thrust force experienced by the rotating spring. Results show that the propulsion characteristics depend strongly on the parameters mentioned above. It is observed that the forward thrust increases in a linear fashion with either of the rotational speed or the fluid viscosity. In addition, the thrust is directly proportional to square of the helical radius and but the thrust force is increased and then decreased based on the peak value to the pitch. Finally, we also present the appropriate flow and pressure fields visualized to support the observations.

Keywords: fluid viscosity, hydrodynamics, similitude, propulsive force

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6608 WWSE School Development in German Christian Schools Revisited: Organizational Development Taken to a Test

Authors: Marco Sewald

Abstract:

WWSE School Development (Wahrnehmungs- und wertorientierte Schulentwicklung) contains surveys on pupils, teachers and parents and enables schools to align the development to the requirements mentioned by these three stakeholders. WWSE includes a derivative set of questions for Christian schools, meeting their specific needs. The conducted research on WWSE is reflecting contemporary questions on school development, questioning the quality of the implementation of the results of past surveys, delivered by WWSE School Development in Christian schools in Germany. The research focused on questions connected to organizational development, including leadership and change management. This is done contoured to the two other areas of WWSE: human resources development and development of school teaching methods. The chosen research methods are: (1) A quantitative triangulation on three sets of data. Data from a past evaluation taken in 2011, data from a second evaluation covering the same school conducted in 2014 and a structured survey among the teachers, headmasters and members of the school board taken within the research. (2) Interviews with teachers and headmasters have been conducted during the research as a second stage to fortify the result of the quantitative first stage. Results: WWSE is supporting modern school development. While organizational development, leadership, and change management are proofed to be important for modern school development, these areas are widespread underestimated by teachers and headmasters. Especially in comparison to the field of human resource development and to an even bigger extent in comparison to the area of development of school teaching methods. The research concluded, that additional efforts in the area of organizational development are necessary to meet modern demands and the research also shows which areas are the most important ones.

Keywords: school as a social organization, school development, school leadership, WWSE, Wahrnehmungs- und wertorientierte Schulentwicklung

Procedia PDF Downloads 226
6607 Piezotronic Effect on Electrical Characteristics of Zinc Oxide Varistors

Authors: Nadine Raidl, Benjamin Kaufmann, Michael Hofstätter, Peter Supancic

Abstract:

If polycrystalline ZnO is properly doped and sintered under very specific conditions, it shows unique electrical properties, which are indispensable for today’s electronic industries, where it is used as the number one overvoltage protection material. Under a critical voltage, the polycrystalline bulk exhibits high electrical resistance but becomes suddenly up to twelve magnitudes more conductive if this voltage limit is exceeded (i.e., varistor effect). It is known that these peerless properties have their origin in the grain boundaries of the material. Electric charge is accumulated in the boundaries, causing a depletion layer in their vicinity and forming potential barriers (so-called Double Schottky Barriers, or DSB) which are responsible for the highly non-linear conductivity. Since ZnO is a piezoelectric material, mechanical stresses induce polarisation charges that modify the DSB heights and as a result the global electrical characteristics (i.e., piezotronic effect). In this work, a finite element method was used to simulate emerging stresses on individual grains in the bulk. Besides, experimental efforts were made to testify a coherent model that could explain this influence. Electron back scattering diffraction was used to identify grain orientations. With the help of wet chemical etching, grain polarization was determined. Micro lock-in infrared thermography (MLIRT) was applied to detect current paths through the material, and a micro 4-point probes method system (M4PPS) was employed to investigate current-voltage characteristics between single grains. Bulk samples were tested under uniaxial pressure. It was found that the conductivity can increase by up to three orders of magnitude with increasing stress. Through in-situ MLIRT, it could be shown that this effect is caused by the activation of additional current paths in the material. Further, compressive tests were performed on miniaturized samples with grain paths containing solely one or two grain boundaries. The tests evinced both an increase of the conductivity, as observed for the bulk, as well as a decreased conductivity. This phenomenon has been predicted theoretically and can be explained by piezotronically induced surface charges that have an impact on the DSB at the grain boundaries. Depending on grain orientation and stress direction, DSB can be raised or lowered. Also, the experiments revealed that the conductivity within one single specimen can increase and decrease, depending on the current direction. This novel finding indicates the existence of asymmetric Double Schottky Barriers, which was furthermore proved by complementary methods. MLIRT studies showed that the intensity of heat generation within individual current paths is dependent on the direction of the stimulating current. M4PPS was used to study the relationship between the I-V characteristics of single grain boundaries and grain orientation and revealed asymmetric behavior for very specific orientation configurations. A new model for the Double Schottky Barrier, taking into account the natural asymmetry and explaining the experimental results, will be given.

Keywords: Asymmetric Double Schottky Barrier, piezotronic, varistor, zinc oxide

Procedia PDF Downloads 267
6606 Association of Phosphorus and Magnesium with Fat Indices in Children with Metabolic Syndrome

Authors: Mustafa M. Donma, Orkide Donma

Abstract:

Metabolic syndrome (MetS) is a disease associated with obesity. It is a complicated clinical problem possibly affecting body composition as well as macrominerals. These parameters gain further attention, particularly in the pediatric population. The aim of this study is to investigate the amount of discrete body composition fractions in groups that differ in the severity of obesity. Also, the possible associations with calcium (Ca), phosphorus (P), magnesium (Mg) will be examined. The study population was divided into four groups. Twenty-eight, 29, 34, and 34 children were involved in Group 1 (healthy), 2 (obese), 3 (morbid obese), and 4 (MetS), respectively. Institutional Ethical Committee approved the study protocol. Informed consent forms were obtained from the participants. The classification of obese groups was performed based upon the recommendations of the World Health Organization. Metabolic syndrome components were defined. Serum Ca, P, Mg concentrations were measured. Within the scope of body composition, fat mass, fat-free mass, protein mass, mineral mass were determined by a body composition monitor using bioelectrical impedance analysis technology. Weight, height, waist circumference, hip circumference, head circumference, and neck circumference values were recorded. Body mass index, diagnostic obesity notation model assessment index, fat mass index, and fat-free mass index values were calculated. Data were statistically evaluated and interpreted. There was no statistically significant difference among the groups in terms of Ca and P concentrations. Magnesium concentrations differed between Group 1 and Group 4. Strong negative correlations were detected between P as well as Mg and fat mass index as well as diagnostic obesity notation model assessment index in Group 4, the group, which comprised morbid obese children with MetS. This study emphasized unique associations of P and Mg minerals with diagnostic obesity notation model assessment index and fat mass index during the evaluation of morbid obese children with MetS. It was also concluded that diagnostic obesity notation model assessment index and fat mass index were more proper indices in comparison with body mass index and fat-free mass index for the purpose of defining body composition in children.

Keywords: children, fat mass, fat-free mass, macrominerals, obesity

Procedia PDF Downloads 153
6605 Evaluation of Information Technology Governance Frameworks for Better Governance in South Africa

Authors: Memory Ranga, Phillip Pretorious

Abstract:

The South African Government has invested a lot of money in Information Technology Governance (ITG) within the Government departments. The ITG framework was spearheaded by the Department of Public Service and Administration (DPSA). This led to the development of a governing ITG DPSA framework and later the Government Wide Enterprise Architecture (GWEA) Framework for assisting the departments to implement ITG. In addition to this, the government departments have adopted the Information Systems Audit and Control Association (ISACA) Control Objectives for Information and Related Technology (COBIT) for ITG processes. Despite all these available frameworks, departments fail to fully capitalise and improve the ITG processes mainly as these are too generic and difficult to apply for specific governance needs. There has been less research done to evaluate the progress on ITG initiatives within the government departments. This paper aims to evaluate the existing ITG frameworks within selected government departments in South Africa. A quantitative research approach was used in this study. Data was collected through an online questionnaire targeting ICT Managers and Directors from government departments. The study is undertaken within a case study and only the Eastern Cape Province was selected for the research. Document review mainly on ITG framework and best practices was also used. Data was analysed using the Google Analytic tools and SPSS. A one–sample Chi-Squared Test was used to verity the evaluation findings. Findings show that there is evidence that the current guiding National governance framework (DPSA) is out dated and does not accommodate the new changes in other governance frameworks. The Eastern Cape Government Departments have spent huge amount of money on ITG but not yet able to identify the benefits of the ITG initiatives. The guiding framework is rigid and does to address some of the departmental needs making it difficult to be flexible and apply the DPSA framework. Furthermore, despite the large budget on ITG, the departments still find themselves with many challenges and unable to improve some of the processes and services. All the engaged Eastern Cape departments have adopted the COBIT framework, but none has been conducting COBIT maturity Assessment which is a functionality of COBIT. There is evidence of too many the ITG frameworks and underutilisation of these frameworks. The study provides a comprehensive evaluation of the ITG frameworks that have been adopted by the South African Government Departments in the Eastern Cape Province. The evaluation guides and recommends the government departments to rethink and adopt ITG frameworks that could be customised to accommodate their needs. The adoption and application of ITG by government departments should assist in better governance and service delivery to the citizens.

Keywords: information technology governance, COBIT, evaluate, framework, governance, DPSA framework

Procedia PDF Downloads 123
6604 Multicriteria for Optimal Land Use after Mining

Authors: Carla Idely Palencia-Aguilar

Abstract:

Mining in Colombia represents around 2% of the GDP (USD 8 billion in 2018), with main productions represented by coal, nickel, gold, silver, emeralds, iron, limestone, gypsum, among others. Sand and Gravel had been decreasing its participation of the GDP with a reduction of 33.2 million m3 in 2015, to 27.4 in 2016, 22.7 in 2017 and 15.8 in 2018, with a consumption of approximately 3 tons/inhabitant. However, with the new government policies it is expected to increase in the following years. Mining causes temporary environmental impacts, once restoration and rehabilitation takes place, social, environmental and economic benefits are higher than the initial state. A way to demonstrate how the mining interventions had contributed to improve the characteristics of the region after sand and gravel mining, the NDVI (Normalized Difference Vegetation Index) from MODIS and ASTER were employed. The histograms show not only increments of vegetation in the area (8 times higher), but also topographies similar to the ones before the intervention, according to the application for sustainable development selected: either agriculture, forestry, cattle raising, artificial wetlands or do nothing. The decision was based upon a Multicriteria analysis for optimal land use, with three main variables: geostatistics, evapotranspiration and groundwater characteristics. The use of remote sensing, meteorological stations, piezometers, sunphotometers, geoelectric analysis among others; provide the information required for the multicriteria decision. For cattle raising and agricultural applications (where various crops were implemented), conservation of products were tested by means of nanotechnology. The results showed a duration of 2 years with no chemicals added for preservation and concentration of vitamins of the tested products.

Keywords: ASTER, Geostatistics, MODIS, Multicriteria

Procedia PDF Downloads 126
6603 Legal Contestation of Non-Legal Norms: The Case of Humanitarian Intervention Norm between 1999 and 2018

Authors: Nazli Ustunes Demirhan

Abstract:

Norms of any nature are subject to pressures of change throughout their lifespans, as they are interpreted and re-interpreted every time they are used rhetorically or practically by international actors. The inevitable contestation of different interpretations may lead to an erosion of the norm, as well as to its strengthening. This paper aims to question the role of formal legality on the change of norm strength, using a norm contestation framework and a multidimensional norm strength conceptualization. It argues that the role of legality is not necessarily linked to the formal legal characteristics of a norm, but is about the legality of the contestation processes. In order to demonstrate this argument, the paper examines the evolutionary path of the humanitarian intervention norm as a case study. Humanitarian intervention, as a norm of very low formal legal characteristics, has been subject to numerous cycles of contestation, demonstrating a fluctuating pattern of norm strength. With the purpose of examining the existence and role of legality in the selected contestation periods from 1999 to 2017, this paper uses process tracing method with a detailed document analysis on the Security Council documents; including decisions, resolutions, meeting minutes, press releases as well as individual country statements. Through the empirical analysis, it is demonstrated that the legality of the contestation processes has a positive effect at least on the authoritativeness dimension of norm strength. This study tries to contribute to the developing dialogue between international relations (IR) and internal law (IL) disciplines with its better-tuned understanding of legality. It connects to further questions in IR/IL nexus, relating to the value added of norm legality, and politics of legalization as well as better international policies for norm reinforcement.

Keywords: humanitarian intervention, legality, norm contestation, norm dynamics, responsibility to protect

Procedia PDF Downloads 153
6602 Closed Urban Block versus Open Housing Estates Structures: Sustainability Surveys in Brno, Czech Republic

Authors: M. Wittmann, G. Kopacik, A. Leitmannova

Abstract:

A prominent place in the spatial arrangement of Czech as well as other post-socialist, Central European cities belongs to 19th century closed urban blocks and the open concrete panel housing estates which were erected during the socialism era in the second half of 20th century. The characteristics of these two fundamentally diverse types of residential structures have, as we suppose, a different impact on the sustainable development of the urban area. The characteristics of these residential structures may influence the ecological stability of the area, its hygienic qualities, the intensity and way of using by various social groups, and also, e.g., the prices of real estates. These and many other phenomena indicate the environmental, social and economic sustainability of the urban area. The proposed research methodology assessed specific indicators of sustainability within a range from 0 to 10 points. 5 points correspond to the general standard in the area, 0 points indicates degradation, and 10 points indicate the highest contribution to sustainable development. The survey results are reflected in the overall sustainability index and in the residents’ satisfaction index. The paper analyses the residential structures in the Central European city of Brno, Czech Republic. The case studies of the urban blocks near the city centre and of the housing estate Brno - Vinohrady are compared. The results imply that a considerable positive impact on the sustainable development of the area should be ascribed to the closed urban blocks near the city centre.

Keywords: City of Brno, closed urban block, open housing estate, urban structure

Procedia PDF Downloads 179
6601 Clinical Evidence of the Efficacy of ArtiCovid (Artemisia Annua Extract) on Covid-19 Patients in DRC

Authors: Md, MCS, MPH Munyangi Wa Nkola Jerome

Abstract:

The pandemic of COVID-19, a recently discovered contagious respiratory disease called SARS-CoV-2 (Severe Acute Respiratory Syndrome-Coronavirus 2 Majority of people infected with SARS-CoV-2: Asymptomatic or mildly ill 14% of patients will develop severe illness requiring hospitalization and oxygen support, and 5% of these will be transferred to an intensive care unit, Urgent need for new treatments that can be used quickly to avoid transfer of patients to intensive care and death. Objective: To evaluate the clinical activity (efficacy) of ArtiCovid Hypothesis: Administration of 3 times a teaspoon per day by COVID patients (symptomatic, mild, or moderate forms) results in the disappearance of symptoms and improvement of biological parameters (including viral suppression). Clinical efficacy: the disappearance of clinical signs after seven days of treatment; reduction in the rate of patients transferred to intensive care units for mechanical ventilation and a decrease in mortality related to this infection Paraclinical efficacy: improvement of biological parameters (mainly d-dimer, CRP) Virological efficacy: suppression of the viral load after seven days of treatment (control test on the seventh day is negative) Pilot study using a standardized solution based on Artemisia annua (ARTICOVID) Obtaining authorization from the health authorities of the province of Central Kongo Recruitment of volunteer patients, mainly in the Kinkanda HospitalCarrying out tests before and after treatment as well as analyses before and after treatment. The protocol obtained the approval of the ethics committee 50 patients who completed the treatment were aged between 2 and 70 years, with an average age of 36 yearsMore half were male (56%). One in four patients was a health professional (25%) Of the 12 health professionals, 4 were physicians. For those who reported the date of onset of the disease, the average duration between the appearance of the first symptoms and the medical consultation was 5 days. The 50 patients put on ARTICOVID were discharged alive with CRP levels substantially normalizedAfter seven to eight days, the control test came back negative. This pilot study suggests that ARTICOVID may be effective against COVID-19 infection.

Keywords: artiCovid, DRC, Covid-19, SARS_COV_2

Procedia PDF Downloads 120
6600 The Effect of Gender Differences on Mate Selection in Private University

Authors: Hui Min Kong, Rajalakshmi A/P Ganesan

Abstract:

The present study was conducted to investigate the effect of gender differences in mate selection in a private university. Mate selection is an important process and decision to the people around the world, especially for single people. The future partner we have chosen could be our lifetime friend, supporter, and lover. Mate selection is important to us, but we have never fully understood the evolution of gender differences in mate selection. Besides, there was an insufficient empirical finding of gender differences in mate selection in Malaysia. Hence, the research would allow us to understand our feelings and thoughts about our future partners. The research null hypotheses have stated that there was no significant difference on 18 mate selections characteristics between males and females. A quantitative method was performed to test the hypotheses through independent t-test. There was a total of 373 heterosexual participants with the age range of 18 to 35 in the study. The instrument used was Factors in choosing a mate developed by Buss and Barnes (1986). Results indicated that females (M= 26.69) were found to be highly valued on refinement and neatness, good financial prospect, dependable character, emotional stability and maturity, desire for home and children, favorable social status or rating, similar religious background, ambition and industriousness, mutual attraction, good health and education and intelligence than males (M= 23.25). These results demonstrated that there were 61.11% significant gender differences in mate selections characteristics. Findings of this research have highlighted the importance of human mate selections in Malaysia. Further research is needed to identify the factors that could have a possible moderating effect of gender differences in mate selection.

Keywords: gender differences, mate selections, evolution, future partner

Procedia PDF Downloads 111
6599 The Automatic Transliteration Model of Images of the Book Hamong Tani Using Statistical Approach

Authors: Agustinus Rudatyo Himamunanto, Anastasia Rita Widiarti

Abstract:

Transliteration using Javanese manuscripts is one of methods to preserve and legate the wealth of literature in the past for the present generation in Indonesia. The transliteration manual process commonly requires philologists and takes a relatively long time. The automatic transliteration process is expected to shorten the time so as to help the works of philologists. The preprocessing and segmentation stage firstly done is used to manage the document images, thus obtaining image script units that will compile input document images free from noise and have the similarity in properties in the thickness, size, and slope. The next stage of characteristic extraction is used to find unique characteristics that will distinguish each Javanese script image. One of characteristics that is used in this research is the number of black pixels in each image units. Each image of Java scripts contained in the data training will undergo the same process similar to the input characters. The system testing was performed with the data of the book Hamong Tani. The book Hamong Tani was selected due to its content, age and number of pages. Those were considered sufficient as a model experimental input. Based on the results of random page automatic transliteration process testing, it was determined that the maximum percentage correctness obtained was 81.53%. The percentage of success was obtained in 32x32 pixel input image size with the 5x5 image window. With regard to the results, it can be concluded that the automatic transliteration model offered is relatively good.

Keywords: Javanese script, character recognition, statistical, automatic transliteration

Procedia PDF Downloads 339
6598 Interlayer Interaction Arising from Lone Pairs in s-Orbitals in 2D Materials

Authors: Yuan Yan

Abstract:

Interlayer interactions or hybridization in van der Waals (vdW) heterostructures of two-dimensional (2D) materials significantly influence their physical characteristics, including layer-dependent electronic and vibrational structures, magic-angle superconductivity, interlayer antiferromagnetism, and interlayer excitons. These interactions are sensitive to a set of interdependent and externally tunable parameters. To fully exploit the potential of these materials, it is crucial to understand the physical origins of interlayer interaction and hybridization. Traditional theories often attribute these interactions to the sharing of electrons via p orbital lone pairs or π electrons, based on the octet rule, which posits that p electrons are the primary occupants of the outermost atomic shells, except in hydrogen. However, our study challenges this prevailing belief. Through geometry-based analysis, we conducted a high-throughput screening of the Materials Project database and identified 1,623 layered materials. By examining the atomic structure and bonding characteristics of surface atoms, we demonstrate that s-orbital lone pairs can also drive interlayer interactions in two-dimensional materials. Using density functional theory, we further analyzed charge distribution and electronic localization. The crystal field and inert pair effect induce a Stark-like phenomenon, leading to energy level splitting and the formation of directional electron clouds. This allows these electrons to directly participate in the hybridization of interlayer wavefunctions without forming chemical bonds. it findings expand the understanding of interlayer interactions, revealing new mechanisms that govern these properties and providing a theoretical foundation for manipulating interlayer phenomena in 2D materials.

Keywords: interlayer interaction, nanomaterials, 2D materials, van der waals, heterostructures

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6597 Study on the Effect of Different Media on Green Roof Water Retention

Authors: Chen Zhi-Wei, Hsieh Wei-Fang

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Taiwan annual rainfall is global average of 2.5 times, plus city excessive development, green constantly to reduced, instead of is big area of artificial base disc, makes Taiwan rainy season during occurred of storm cannot timely of emissions, led to flood constantly, and rain also cannot was retained again using, led to city hydrological balance suffered damage, and to Regulation city of by brings of negative effect, increased green covered rate became most effective of method, and city land limited, so roof green gradually became a alternative program. Green roofs have become one of the Central and local government policy initiatives for urban development, in foreign countries, such as the United States, and Japan, and Singapore etc. Development of roof greening as an important policy, has become a trend of the times. In recent years, many experts and scholars are also on the roof greening all aspects of research, mostly for green roof for the environmental impact of benefits, such as: carbon reduction, cooling, thermostat, but research on the benefits of green roofs under water cut but it is rare. Therefore, this research literature from green roof in to view and analyze what kind of medium suitable for roof greening and use of green base plate combination simulated green roof structure, via different proportions of the medium with water retention plate and drainage board, experiment with different planting base plate combination of water conservation performance. Research will want to test the effect of roof planting base mix, promotion of relevant departments and agencies in future implementation of green roofs, prompted the development of green roofs, which in the end Taiwan achieve sustainable development of the urban environment help.

Keywords: thin-layer roof greening and planting medium, water efficiency

Procedia PDF Downloads 354