Search results for: state feedback
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8388

Search results for: state feedback

5868 Exploring the Impact of Artificial Intelligence (AI) in the Context of English as a Foreign Language (EFL): A Comprehensive Bibliometric Study

Authors: Kate Benedicta Amenador, Dianjian Wang, Bright Nkrumah

Abstract:

This extensive bibliometric study explores the dynamic influence of artificial intelligence in the field of English as a Foreign Language (EFL) between 2012 and 2024. The study, which examined 4,500 articles from Google Scholar, Modern Language Association Linguistics Abstracts, Web of Science, Scopus, Researchgate, and library genesis databases, indicates that AI integration in EFL is on the rise. This notable increase is ascribed to a variety of transformative events, including increased academic funding for higher education and the COVID-19 epidemic. The results of the study identify leading contributors, prominent authors, publishers and sources, with the United States, China and the United Kingdom emerging as key contributors. The co-occurrence analysis of key terms reveals five clusters highlighting patterns in AI-enhanced language instruction and learning, including evaluation strategies, educational technology, learning motivation, EFL teaching aspects, and learner feedback. The study also discusses the impact of various AIs in enhancing EFL writing skills with software such as Grammarly, Quilbot, and Chatgpt. The current study recognizes limitations in database selection and linguistic constraints. Nevertheless, the results provide useful insights for educators, researchers and policymakers, inspiring and guiding a cross-disciplinary collaboration and creative pedagogical techniques and approaches to teaching and learning in the future.

Keywords: artificial intelligence, bibliometrics study, VOSviewer visualization, English as a foreign language

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5867 Analysis of Risks in Financing Agriculture a Case of Agricultural Cooperatives in Benue State, Nigeria

Authors: Odey Moses Ogah, Felix Terhemba Ikyereve

Abstract:

The study was carried out to analyzed risks in financing agriculture by agricultural cooperatives in Benue State, Nigeria. The study made use of research questionnaires for data collection. A multistage sampling technique was used to select a sample of 210 respondents from 21 agricultural cooperatives. Both descriptive and inferential statistics were employed in data analysis. Loan defaulting (66.7%) and reduction in savings by members (51.4%) were the major causes of risks faced by agricultural cooperatives in financing agriculture in the study area. Other causes include adverse changes in commodity prices (48.6%), disaster (45.7%), among others. It was found that risks adversely influence the profitability and competition of agricultural cooperatives (82.9%). Multiple regression analysis results showed that the coefficient of multiple determinations was 0.67, implying that the explanatory variables included in the model accounted for 67% of the variation in the level of profitability of agricultural cooperatives. The number of loans, average amount of loan and the interest rate were significant and important determinants of profitability of the cooperatives. The majority of the respondents (88.6%) made use of loan guarantors as a strategy of managing loan default/no repayment. It was found that the majority (70%) of the respondents were faced with the challenge of lack of insurance cover. The study recommends that agricultural cooperative officials should be encouraged to undergo formal training and education to easily acquire administrative skills in the management of agricultural loans; Farmer's loan size should be increased and released on time to enable them to use it effectively. Policies that enhance insuring farm activities should be put in place to discourage farmers from risk aversion.

Keywords: agriculture, analysis, cooperative, finance, risks

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5866 Rival Conceptions of Sovereignty in Modern South Asian Political Thought: An Analysis Through the Writings of Maulana Syed Abul Ala Maududi and Maulana Hifzurrahman Seoharvi

Authors: Mohammad Saif

Abstract:

In the post-Westphalianworld order, the concept of sovereignty has been a fundamental area of inquiry in Political Science, International Relations, and International Law. Modern Islamic political thought has also dedicated a fair share of debate on the subject. The debate fundamentally revolves around the ‘ontological differentiation’ between western and Islamic political thought. While the centrality of the individual in western political thought regards the individual as the center of universe, Islamic Political thought provides that space to God. The modern liberal democratic principles suggest sovereignty as one of the major attributes of modern nation state; Islamists regard sovereignty as an attribute of God. However, the position regarding God’ssovereignty in Islamic political thought is not coherent in conception. Some scholars regard such a position as ‘the political interpretation of Islam’. This paper is an attempt to first analyze the fundamental discord between two rival political ideologies (western and Islamic), and then forward a debate on the subject of sovereignty in South Asian Islamic Political thought, particularly between Syed Abul Ala Maududi (ideological father of modern islamist movements) andHifzurrahmanSeoharvi (lesser known in Academia but highly influential in shaping Deobandi position of principles related to political nature of Islamic theology). Maududi regardssovereignty as an attribute of God and the rulers as subservient to Gods will, Seoharvi suggests that God's sovereignty does not entail that the caliph or amir cannot be a ruler or hakim, nor can his command or hukum be an order. Certain references have also been made to contemporary scholars like Sayidd Qutub, Rashid al Ghanouchi, who in one way or the other have contributed to the debate on ‘sovereignty in Islamic thought’.

Keywords: nation state, sovereigty, sovereignty of God (Hakimmiyah), deoband

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5865 Reproductive Governmentality in Mexico: Production, Control and Regulation of Contraceptive Practices in a Public Hospital

Authors: Ivan Orozco

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Introduction: Forced contraception constitutes part of an effort to control the life and reproductive capacity of women through public health institutions. This phenomenon has affected many Mexican women historically and still persists nowadays. The notion of reproductive governmentality refers to the mechanisms through which different historical configurations of social actors (state institutions, churches, donor agents, NGOs, etc.) use legislative controls, economic incentives, moral mandates, direct coercion, and ethical incitements, to produce, monitor and control reproductive behaviors and practices. This research focuses on the use of these mechanisms by the Mexican State to control women's contraceptive practices in a public hospital. Method: An Institutional Ethnography was carried out, with the objective of knowing women's experiences from their own perspective, as they occur in their daily lives, but at the same time, discovering the structural elements that shape the discourses that promote women's contraception, even against their will. The fieldwork consisted in an observation of the dynamics between different participants within a public hospital and the conduction of interviews with the medical and nursing staff in charge of family planning services, as well as women attending the family planning office. Results: Public health institutions in Mexico are state tools to control and regulate reproduction. There are several strategies that are used for this purpose, for example, health personnel provide insufficient or misleading information to ensure that women agree to use contraceptives; health institutions provide economic incentives to the members of the health staff who reach certain goals in terms of contraceptive placement; young women are forced to go to the family planning service, regardless of the reason they went to the clinic; health campaigns are carried out, consisting of the application of contraceptives outside the health facilities, directly in the communities of people who visit the hospital less frequently. All these mechanisms seek for women to use contraceptives, from the women’s perspective; however, the reception of these discourses is ambiguous. While, for some women, the strategies become coercive mechanisms to use contraceptives against their will, for others, they represent an opportunity to take control over their reproductive lives. Conclusion: Since 1974, the Mexican government has implemented campaigns for the promotion of family planning methods as a means to control population growth. Although it is established in several legislations that the counselling must be carried out with a gender and human rights perspective, always respecting the autonomy of people, these research testify that health personnel uses different strategies to force some women to use contraceptive methods, thereby violating their reproductive rights.

Keywords: feminist research, forced contraception, institutional ethnography, reproductive. governmentality

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5864 How Do L1 Teachers Assess Haitian Immigrant High School Students in Chile?

Authors: Gloria Toledo, Andrea Lizasoain, Leonardo Mena

Abstract:

Immigration has largely increased in Chile in the last 20 years. About 6.6% of our population is foreign, from which 14.3% is Haitian. Haitians are between 15 and 29 years old and have come to Chile escaping from a social crisis. They believe that education and work will help them do better in life. Therefore, rates of Haitian students in the Chilean school system have also increased: there were 3,121 Haitian students enrolled in 2017. This is a challenge for the public school, which takes in young people who must face schooling, social immersion and learning of a second language simultaneously. The linguistic barrier affects both students’ and teachers’ adaptation process, which has an impact on the students’ academic performance and consequent acquisition of Spanish. In order to explore students’ academic performance and interlanguage development, we examined how L1 teachers assess Haitian high school students’ written production in Spanish. With this purpose, teachers were asked to use a specially designed grid to assess correction, accommodation, lexical and analytical complexity, organization and fluency of both Haitian and Chilean students. Parallelly, texts were approached from an error analysis perspective. Results from grids and error analysis were then compared. On the one hand, it has been found that teachers give very little feedback to students apart from scores and grades, which does not contribute to the development of the second language. On the other hand, error analysis has yielded that Haitian students are in a dynamic process of the acquisition of Spanish, which could be enhanced if L1 teacher were aware of the process of interlanguage developmen.

Keywords: assessment, error analysis, grid, immigration, Spanish aquisition, writing

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5863 Challenges and Future Prospects of Teaching English in Secondary Schools of Jharkhand Board: An Extensive Survey of the Present Status

Authors: Neha Toppo

Abstract:

Plans and programs for successful secondary education are incomplete without the inclusion of teaching English as an important area. Even after sixteen years of the formation of Jharkhand as a separate state, the students are still struggling to achieve quality education of English. This paper intends to account the present condition of teaching English in Jharkhand board secondary level schools through discussion on various issues of English language teaching, language need and learning challenges of its students. The study is to analyze whether the learning environment, teaching methods and materials, teaching resources, goals of language curriculum are appropriately convincing for the students of the board or require to be reanalyzed and also to provide appropriate suggestions for improvement. Immediate attention must be drawn towards the problem for benefitting those students, who despite their knowledge and talent are lagging behind in numerous fields only due to the lack of proficiency in English. The data and discussion provided are on the basis of a survey, in which semi structured interview with teachers, students and administrators in several schools including both rural and urban area has been taken. Questionnaire, observation and testing were used as important tools. The survey has been conducted in Ranchi district, as it covers large geographical area which includes number of villages and at the same time several towns. The district primarily possesses tribes as well as different class of people including immigrants from all over and outside Jharkhand with their social, economical strata. The observation makes it clear that the English language teaching at the state board is not complementing its context and the whole language teaching system should be re-examined to establish learner oriented environment.

Keywords: material, method, secondary level, teaching resources

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5862 Determining Which Material Properties Resist the Tool Wear When Machining Pre-Sintered Zirconia

Authors: David Robert Irvine

Abstract:

In the dental restoration sector, there has been a shift to using zirconia. With the ever increasing need to decrease lead times to deliver restorations faster the zirconia is machined in its pre-sintered state instead of grinding the very hard sintered state. As with all machining, there is tool wear and while investigating the tooling used to machine pre-sintered zirconia it became apparent that the wear rate is based more on material build up and abrasion than it is on plastic deformation like conventional metal machining. It also came to light that the tool material can currently not be selected based on wear resistance, as there is no data. Different works have analysed the effect of the individual wear mechanism separately using similar if not the same material. In this work, the testing method used to analyse the wear was a modified from ISO 8688:1989 to use the pre-sintered zirconia and the cutting conditions used in dental to machine it. This understanding was developed through a series of tests based in machining operations, to give the best representation of the multiple wear factors that can occur in machining of pre-sintered zirconia such as 3 body abrasion, material build up, surface welding, plastic deformation, tool vibration and thermal cracking. From the testing, it found that carbide grades with low trans-granular rupture toughness would fail due to abrasion while those with high trans-granular rupture toughness failed due to edge chipping from build up or thermal properties. The results gained can assist the development of these tools and the restorative dental process. This work was completed with the aim of assisting in the selection of tool material for future tools along with a deeper understanding of the properties that assist in abrasive wear resistance and material build up.

Keywords: abrasive wear, cemented carbide, pre-sintered zirconia, tool wear

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5861 Hijabs, Burqas and Burqinis: Freedom of Religious Expression In The French Public Sphere

Authors: John Tate

Abstract:

In 2004, the French Parliament banned the “hijab” in public schools, and in 2010 it prohibited the “burqa” and “niqab” in “public places.” The result was a “secular” outcome involving the removal of these garments, often identified with Islamic religious and cultural practice, from the French public sphere. Yet in 2016, the French local council bans on the “burqini” were overruled by France’s highest administrative court, the Conseil d’État, allowing for their retention in the public sphere. Unlike the burqa and hijab bans, the burqini bans produced significant divisions at the highest echelons of the French political class, with the Prime Minister, Manuel Valls, and the President, François Hollande, finding themselves at odds on the issue. This article seeks to achieve four aims. It seeks to (a) explain the contrary outcomes between key French state institutions, such as the Conseil d’État and the French Parliament, concerning the hijab and burqa bans, and the Conseil d’État and French local councils, concerning the burqini bans; (b) to do so by identifying two qualitatively distinct, and at times incompatible, conceptions of laïcité, present within official French public discourse, and applied by these French state institutions to underwrite these respective outcomes; (c) explain why, given these contrary conceptions of laïcité, and these contrary outcomes, the widespread identification of laïcité with “secularism” is both misleading and inaccurate; and (d) provide an explanation why senior members of the French political class were divided on the burqini bans when they were not divided on the nation-wide prohibitions of the hijab in public schools and the burqa in public places. In regard to this last question, the article seeks to ask why the Burqini was “different”?

Keywords: liberalism, republicanism, laïcité, citizenship

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5860 Effect of Micro Credit Access on Poverty Reduction among Small Scale Women Entrepreneurs in Ondo State, Nigeria

Authors: Adewale Oladapo, C. A. Afolami

Abstract:

The study analyzed the effect of micro credit access on poverty reduction among small scale women entrepreneurs in Ondo state, Nigeria. Primary data were collected in a cross-sectional survey of 100 randomly selected woman entrepreneurs. These were drawn in multistage sampling process covering four local government areas (LGAS). Data collected include socio economics characteristics of respondents, access to micro credit, sources of micro credit, and constraints faced by the entrepreneur in sourcing for micro credit. Data were analyzed using descriptive statistics, Foster, Greer and Thorbecke (FGT) index of poverty measure, Gini coefficients and probit regression analysis. The study found that respondents sampled for the survey were within the age range of 31-40 years with mean age 38.6%. Mostly (56.0%) of the respondents were educated to the tune of primary school. Majority (87.0%) of the respondents were married with fairly large household size of (4-5). The poverty index analysis revealed that most (67%) of the sample respondents were poor. The result of the Probit regression analyzed showed that income was a significant variable in micro credit access, while the result of the Gini coefficient revealed a very high income inequality among the respondents. The study concluded that most of the respondents were poor and return on investment (income) was an important variable that increased the chance of respondents in sourcing for micro-credit loan and recommended that income realized by entrepreneur should be properly documented to facilitate loan accessibility.

Keywords: entrepreneurs, income, micro-credit, poverty

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5859 Human Rights and Fundamental Freedoms in Crisis as Viewed during Bangladesh Parliamentary Election-2018 and Afterwards: A Contestant's Perspective on Social Measures

Authors: Mohammad S. Islam

Abstract:

Elections in Bangladesh are always controversial, and sometimes it becomes a violent affair when state power is combined with politics. Despite the commitment of the ruling party- the polling government to ensure free, fair, and credible elections, the participants of opposition parties and the general voters became very disappointed, terribly frustrated, and severely shocked. It happened when numerous claims of serious irregularities of vote rigging and violence came out in broad daylight during the election. This paper addresses the issues of how the ruling party created frightening and a horror situation to make people silent over electoral fraud and violent incidents, including gang rape. It also seeks to demonstrate that election-2018 was simply the deceptive action of the ruling party to legitimate their power, but not to provide a minimum opportunity for voters to exercise their fundamental right to vote. The fundamental freedom and the rule of law seemed to be ignored completely in this election process and afterwards. With the help of state machinery, the government of the ruling party violated human rights, restricted fundamental freedoms, and humiliated social protection & dignity. The contestant’s views as witnessed and relevant literatures are cited first for conceptual understanding. Then, the paper will examine how a new dimension of circumstantial social measures related to sustained protection can reduce all kinds of violence against humanity towards establishing a peaceful democratic society. Finally, this paper interprets the key findings and considers wider implications.

Keywords: electoral fraud, human rights, sustained protection, social measures, vote rigging

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5858 Executing the Law: The Practical Absence of Law and Its Effects on Death Row Inmates and Their Families in Egypt

Authors: Amira M. Othman

Abstract:

Despite the massive array of literature that engages with the Egyptian legislative system on a theoretical level, very little attention has been dedicated to the comparison between the legislative clauses on the one hand, and the (absence of their) real-world implementation on the other. This paper starts with this discrepancy, focusing on the legal proceedings in some recent cases dubbed ‘political,’ in which defendants received death sentences. Then, it sheds light on the trend of practical disregard of the law on behalf of the criminal justice apparatuses (whether security forces, public prosecution offices, lawyers, judges, prison wardens, and executioners) through the examination of case files and the conduction of interviews with some defense lawyers in the cases in question. It also identifies the resultant state of confusion among prison staff, as manifest in their treatment of defendants even before the death sentences against them is pronounced; in other words, the application of some aspects of the law in certain cases, and their simultaneous disregard of others. Then, the paper explores the effects of such execution of the law on the death row inmates, as it identifies the different strategies through which defendants who are sentenced to death appropriate a number of legal clauses to their benefit, thereby embarrassing - or highly irritating - the judges that pronounce their death sentences. In addition to appropriation, other strategies include the contestation of the law and their presence before the courts in general, as well as the complete disregard and dismissal of the legal system altogether. Finally, the paper investigates the consequent conceptual effect on the first degree families of death row inmates, namely how their daily encounters with the Egyptian legislative system - particularly its emphasis on the absence of the otherwise binding local legislation - continue to shape their conceptions of the ‘law,’ of ‘justice,’ and their trust in the ‘state.’

Keywords: death penalty, Egyptian law absence, justice, political cases

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5857 Some Imaginative Geomorphosites in Malaysia: Study on Their Formations and Geotourism Potentials

Authors: Dony Adriansyah Nazaruddin, Mohammad Muqtada Ali Khan

Abstract:

This paper aims to present some imaginative geomorphological sites in Malaysia. This study comprises desk study and field study. Desk study was conducted by reviewing some literatures related to the topic and some geomorphosites in Malaysia. Field study was organized in 2013 and 2014 to investigate the recent situation of these sites and to take some measurements, photographs and rock samples. Some examples of imaginative geomorphosites all over Malaysia have been identified for this purpose. In Peninsular Malaysia, some geomorphosites in Langkawi Islands (the state of Kedah) have imaginative features such as a “turtle” atop the limestone hill of Setul Formation at the Kilim Geoforest Park, a “shoe” at the Kasut island of the Kilim Geoforest Park, a “lying pregnant lady” at the Dayang Bunting island of the Dayang Bunting Marble Geoforest Park, and a “ship” of the Singa Kecil island. Meanwhile, some other examples are from the state of Kelantan, such as a mogote hill with a “human face looking upward” at Gunung Reng, Jeli District and a “boat rock” at Mount Chamah, Gua Musang District. In East Malaysia, there is only one example can be identified, it is the “Abraham Lincoln’s face” at the Deer Cave, Gunung Mulu National Park, Sarawak. Karst landforms dominate the imaginative geomorphosites in Malaysia. The formations of these features are affected by some endogenic and exogenic processes, such as tectonic uplift, weathering (including solution), erosion, and so on. This study will recommend that these imaginative features should be conserved and developed for some purposes, such as research, education, and geotourism development in Malaysia.

Keywords: geomorphosite, geotourism, earth processes, karst landforms, Malaysia

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5856 The Survey Research and Evaluation of Green Residential Building Based on the Improved Group Analytical Hierarchy Process Method in Yinchuan

Authors: Yun-na Wu, Zhen Wang

Abstract:

Due to the economic downturn and the deterioration of the living environment, the development of residential buildings as high energy consuming building is gradually changing from “extensive” to green building in China. So, the evaluation system of green building is continuously improved, but the current evaluation work has the following problems: (1) There are differences in the cost of the actual investment and the purchasing power of residents, also construction target of green residential building is single and lacks multi-objective performance development. (2) Green building evaluation lacks regional characteristics and cannot reflect the different regional residents demand. (3) In the process of determining the criteria weight, the experts’ judgment matrix is difficult to meet the requirement of consistency. Therefore, to solve those problems, questionnaires which are about the green residential building for Ningxia area are distributed, and the results of questionnaires can feedback the purchasing power of residents and the acceptance of the green building cost. Secondly, combined with the geographical features of Ningxia minority areas, the evaluation criteria system of green residential building is constructed. Finally, using the improved group AHP method and the grey clustering method, the criteria weight is determined, and a real case is evaluated, which is located in Xing Qing district, Ningxia. A conclusion can be obtained that the professional evaluation for this project and good social recognition is basically the same.

Keywords: evaluation, green residential building, grey clustering method, group AHP

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5855 Vertically Coupled III-V/Silicon Single Mode Laser with a Hybrid Grating Structure

Authors: Zekun Lin, Xun Li

Abstract:

Silicon photonics has gained much interest and extensive research for a promising aspect for fabricating compact, high-speed and low-cost photonic devices compatible with complementary metal-oxide-semiconductor (CMOS) process. Despite the remarkable progress made on the development of silicon photonics, high-performance, cost-effective, and reliable silicon laser sources are still missing. In this work, we present a 1550 nm III-V/silicon laser design with stable single-mode lasing property and robust and high-efficiency vertical coupling. The InP cavity consists of two uniform Bragg grating sections at sides for mode selection and feedback, as well as a central second-order grating for surface emission. A grating coupler is etched on the SOI waveguide by which the light coupling between the parallel III-V and SOI is reached vertically rather than by evanescent wave coupling. Laser characteristic is simulated and optimized by the traveling-wave model (TWM) and a Green’s function analysis as well as a 2D finite difference time domain (FDTD) method for the coupling process. The simulation results show that single-mode lasing with SMSR better than 48dB is achievable, and the threshold current is less than 15mA with a slope efficiency of around 0.13W/A. The coupling efficiency is larger than 42% and possesses a high tolerance with less than 10% reduction for 10 um horizontal or 15 um vertical dislocation. The design can be realized by standard flip-chip bonding techniques without co-fabrication of III-V and silicon or precise alignment.

Keywords: III-V/silicon integration, silicon photonics, single mode laser, vertical coupling

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5854 Determination of Selected Engineering Properties of Giant Palm Seeds (Borassus Aethiopum) in Relation to Its Oil Potential

Authors: Rasheed Amao Busari, Ahmed Ibrahim

Abstract:

The engineering properties of giant palms are crucial for the reasonable design of the processing and handling systems. The research was conducted to investigate some engineering properties of giant palm seeds in relation to their oil potential. The ripe giant palm fruit was sourced from some parts of Zaria in Kaduna State and Ado Ekiti in Ekiti State, Nigeria. The mesocarps of the fruits collected were removed to obtain the nuts, while the collected nuts were dried under ambient conditions for several days. The actual moisture content of the nuts at the time of the experiment was determined using KT100S Moisture Meter, with moisture content ranged 17.9% to 19.15%. The physical properties determined are axial dimension, geometric mean diameter, arithmetic mean diameter, sphericity, true and bulk densities, porosity, angles of repose, and coefficients of friction. The nuts were measured using a vernier caliper for physical assessment of their sizes. The axial dimensions of 100 nuts were taken and the result shows that the size ranges from 7.30 to 9.32cm for major diameter, 7.2 to 8.9 cm for intermediate diameter, and 4.2 to 6.33 for minor diameter. The mechanical properties determined were compressive force, compressive stress, and deformation both at peak and break using Instron hydraulic universal tensile testing machine. The work also revealed that giant palm seed can be classified as an oil-bearing seed. The seed gave 18% using the solvent extraction method. The results obtained from the study will help in solving the problem of equipment design, handling, and further processing of the seeds.

Keywords: giant palm seeds, engineering properties, oil potential, moisture content, and giant palm fruit

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5853 Plastic Waste Sorting by the People of Dakar

Authors: E. Gaury, P. Mandausch, O. Picot, A. R. Thomas, L. Veisblat, L. Ralambozanany, C. Delsart

Abstract:

In Dakar, demographic and spatial growth was accompanied by a 50% increase in household waste between 1988 and 2008 in the city. In addition, a change in the nature of household waste was observed between 1990 and 2007. The share of plastic increased by 15% between 2004 and 2007 in Dakar. Plastics represent the seventh category of household waste, the most produced per year in Senegal. The share of plastic in household and similar waste is 9% in Senegal. Waste management in the city of Dakar is a complex process involving a multitude of formal and informal actors with different perceptions and objectives. The objective of this study was to understand the motivations that could lead to sorting action, as well as the perception of plastic waste sorting within the Dakar population (households and institutions). The problematic of this study was as follows: what may be the factors playing a role in the sorting action? In an attempt to answer this, two approaches have been developed: (1) An exploratory qualitative study by semi-structured interviews with two groups of individuals concerned by the sorting of plastic waste: on the one hand, the experts in charge of waste management and on the other the households-producers of waste plastics. This study served as the basis for formulating the hypotheses and thus for the quantitative analysis. (2) A quantitative study using a questionnaire survey method among households producing plastic waste in order to test the previously formulated hypotheses. The objective was to have quantitative results representative of the population of Dakar in relation to the behavior and the process inherent in the adoption of the plastic waste sorting action. The exploratory study shows that the perception of state responsibility varies between institutions and households. Public institutions perceive this as a shared responsibility because the problem of plastic waste affects many sectors (health, environmental education, etc.). Their involvement is geared more towards raising awareness and educating young people. As state action is limited, the emergence of private companies in this sector seems logical as they are setting up collection networks to develop a recycling activity. The state plays a moral support role in these activities and encourages companies to do more. The study of the understanding of the action of sorting plastic waste by the population of Dakar through a quantitative analysis was able to demonstrate the attitudes and constraints inherent in the adoption of plastic waste sorting.Cognitive attitude, knowledge, and visible consequences have been shown to correlate positively with sorting behavior. Thus, it would seem that the population of Dakar is more sensitive to what they see and what they know to adopt sorting behavior.It has also been shown that the strongest constraints that could slow down sorting behavior were the complexity of the process, too much time and the lack of infrastructure in which to deposit plastic waste.

Keywords: behavior, Dakar, plastic waste, waste management

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5852 Understanding the Social Movements around the ‘Rohingya Crisis’ within the Political Process Model

Authors: Aklima Jesmin, Ubaidur Rob, M. Ashrafur Rahman

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Rohingya population of Arakan state in Myanmar are one the most persecuted ethnic minorities in this 21st century. According to the Universal Declaration of Human Rights (UDHR), all human beings are born free, equal in dignity and rights. However, these populations are systematically excluded from this universal proclamation of human rights as they are Rohingya, which signify ‘other’. Based on the accessible and available literatures about Rohingya issue, this study firstly found there are chronological pattern of human rights violations against the ethnic Rohingya which follows the pathology of the Holocaust in this 21st century of human civilization. These violations have been possible due to modern technology, bureaucracy which has been performed through authorization, routinization and dehumanization; not only in formal institutions but in the society as a whole. This kind of apparently never-ending situation poses any author with the problem of available many scientific articles. The most important sources are, therefore the international daily newspapers, social media and official webpage of the non-state actors for nitty-gritty day to day update. Although it challenges the validity and objectivity of the information, but to address the critical ongoing human rights violations against Rohingya population can become a base for further work on this issue. One of the aspects of this paper is to accommodate all the social movements since August 2017 to date. The findings of this paper is that even though it seemed only human rights violations occurred against Rohingya historically but, simultaneously the process of social movements had also started, can be traced more after the military campaign in 2017. Therefore, the Rohingya crisis can be conceptualized within one ‘campaign’ movement for justice, not as episodic events, especially within the Political Process Model than any other social movement theories. This model identifies that the role of international political movements as well as the role of non-state actors are more powerful than any other episodes of violence conducted against Rohinyga in reframing issue, blaming and shaming to Myanmar government and creating the strategic opportunities for social changes. The lack of empowerment of the affected Rohingya population has been found as the loop to utilize this strategic opportunity. Their lack of empowerment can also affect their capacity to reframe their rights and to manage the campaign for their justice. Therefore, this should be placed at the heart of the international policy agenda within the broader socio-political movement for the justice of Rohingya population. Without ensuring human rights of Rohingya population, achieving the promise of the united nation’s sustainable development goals - no one would be excluded – will be impossible.

Keywords: civilization, holocaust, human rights violation, military campaign, political process model, Rohingya population, sustainable development goal, social justice, social movement, strategic opportunity

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5851 LiTa2PO8-based Composite Solid Polymer Electrolytes for High-Voltage Cathodes in Lithium-Metal Batteries

Authors: Kumlachew Zelalem Walle, Chun-Chen Yang

Abstract:

Solid-state Lithium metal batteries (SSLMBs) that contain polymer and ceramic solid electrolytes have received considerable attention as an alternative to substitute liquid electrolytes in lithium metal batteries (LMBs) for highly safe, excellent energy storage performance and stability under elevated temperature situations. Here, a novel fast Li-ion conducting material, LiTa₂PO₈ (LTPO), was synthesized and electrochemical performance of as-prepared powder and LTPO-incorporated composite solid polymer electrolyte (LTPO-CPE) membrane were investigated. The as-prepared LTPO powder was homogeneously dispersed in polymer matrices, and a hybrid solid electrolyte membrane was synthesized via a simple solution-casting method. The room temperature total ionic conductivity (σt) of the LTPO pellet and LTPO-CPE membrane were 0.14 and 0.57 mS cm-1, respectively. A coin battery with NCM811 cathode is cycled under 1C between 2.8 to 4.5 V at room temperature, achieving a Coulombic efficiency of 99.3% with capacity retention of 74.1% after 300 cycles. Similarly, the LFP cathode also delivered an excellent performance at 0.5C with an average Coulombic efficiency of 100% without virtually capacity loss (the maximum specific capacity is at 27th: 138 mAh g−1 and 500th: 131.3 mAh g−1). These results demonstrates the feasibility of a high Li-ion conductor LTPO as a filler, and the developed polymer/ceramic hybrid electrolyte has potential to be a high-performance electrolyte for high-voltage cathodes, which may provide a fresh platform for developing more advanced solid-state electrolytes.

Keywords: li-ion conductor, lithium-metal batteries, composite solid electrolytes, liTa2PO8, high-voltage cathode

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5850 Microwave Single Photon Source Using Landau-Zener Transitions

Authors: Siddhi Khaire, Samarth Hawaldar, Baladitya Suri

Abstract:

As efforts towards quantum communication advance, the need for single photon sources becomes imminent. Due to the extremely low energy of a single microwave photon, efforts to build single photon sources and detectors in the microwave range are relatively recent. We plan to use a Cooper Pair Box (CPB) that has a ‘sweet-spot’ where the two energy levels have minimal separation. Moreover, these qubits have fairly large anharmonicity making them close to ideal two-level systems. If the external gate voltage of these qubits is varied rapidly while passing through the sweet-spot, due to Landau-Zener effect, the qubit can be excited almost deterministically. The rapid change of the gate control voltage through the sweet spot induces a non-adiabatic population transfer from the ground to the excited state. The qubit eventually decays into the emission line emitting a single photon. The advantage of this setup is that the qubit can be excited without any coherent microwave excitation, thereby effectively increasing the usable source efficiency due to the absence of control pulse microwave photons. Since the probability of a Landau-Zener transition can be made almost close to unity by the appropriate design of parameters, this source behaves as an on-demand source of single microwave photons. The large anharmonicity of the CPB also ensures that only one excited state is involved in the transition and multiple photon output is highly improbable. Such a system has so far not been implemented and would find many applications in the areas of quantum optics, quantum computation as well as quantum communication.

Keywords: quantum computing, quantum communication, quantum optics, superconducting qubits, flux qubit, charge qubit, microwave single photon source, quantum information processing

Procedia PDF Downloads 91
5849 Using Assessment Criteria as a Pedagogic Tool to Develop Argumentative Essay Writing

Authors: Sruti Akula

Abstract:

Assessment criteria are mostly used for assessing skills like writing and speaking. However, they could be used as a pedagogic tool to develop writing skills. A study was conducted with higher secondary learners (Class XII Kendriya Vidyalaya) to investigate the effectiveness of assessment criteria to develop argumentative essay writing. In order to raise awareness about the features of argumentative essay, assessment criteria were shared with the learners. Along with that, self-evaluation checklists were given to the learners to guide them through the writing process. During the study learners wrote multiple drafts with the help of assessment criteria, self-evaluation checklists and teacher feedback at different stages of their writing. It was observed that learners became more aware of the features of argumentative essay which in turn improved their argumentative essay writing. In addition the self evaluation checklists imporved their ability to reflect on their work there by increasing learner autonomy in the class. Hence, it can be claimed that both assessment criteria and self evaluation checklists are effective pedagogic tools to develop argumentative essay writing. Thus, teachers can be trained to create and use tools like assessment criteria and self-evaluation checklists to develop learners’ writing skills in an effective way. The presentation would discuss the approach adopted in the study to teach argumentative essay writing along with the rationale. The tools used in the study would be shared and the data collected in the form of written scripts, self-evaluation checklists and student interviews will be analyzed to validate the claims. Finally, the practical implication of the study like the ways of using assessment criteria and checklists to raise learner awareness and autonomy, using such tools to keep the learners informed about the task requirements and genre features, and the like will be put forward.

Keywords: argumentative essay writing, assessment criteria, self evaluation checklists, pedagogic

Procedia PDF Downloads 504
5848 Effect of Instructional Materials on Academic Performance in Heat Transfer Concept among Secondary School Physics Students in Fagge Educational Zone, Kano State, Nigeria

Authors: Shehu Aliyu

Abstract:

This study investigated the effects of instructional materials on academic achievement among senior secondary school students on the concept of Heat Transfer in physics in Fagge Educational Zone, Kano State Nigeria. The population consisted of SSII students from 10 public schools. Out of this, 87 students were randomly selected from which 24 males and 22 females formed the experimental group and 41 students as control group. A quasi experiential design with pretest and post-test for both the groups was adopted. Two research questions and null hypotheses guided the conduct of the study. The experimental group was exposed to teaching using instructional materials while the control group was taught using the normal lecture mode. Head Transfer Performance Test (HTPT) was used for data collection. The instrument was validated by experts in the science education field. A Pearson Product Moment Correlation (PPMC) was used to determine the reliability co-efficient and was found to be r=0.83. The research questions were answered using descriptive statistics while the hypotheses were tested at p≤ 0.05 level of significance using t-test. The result obtained from the data analysis showed that students in experimental group performed significantly better than those in the control group and that there was no significant difference in the academic performance between male and female students in the experimental group. Based on the findings of this study, it was recommended among others that the physics teachers should be receiving regular training on the importance of using instructional materials whether ready made or improved in their teaching.

Keywords: heat transfer, physics, instructional materials, academic performance

Procedia PDF Downloads 176
5847 Barriers to Marital Expectation among Individuals with Hearing Impairment in Oyo State

Authors: Adebomi M. Oyewumi, Sunday Amaize

Abstract:

The study was designed to examine the barriers to marital expectations among unmarried persons with hearing impairment in Oyo State, Nigeria. Descriptive survey research design was adopted. Purposive sampling technique was used to select one hundred participants made up forty-four (44) males and fifty-six (56) females, all with varying degrees of hearing impairment. Eight research questions were raised and answered. The instrument used was Marital Expectations Scale with reliability coefficient of 0.86. Data was analyzed using descriptive statistics tools of frequency count and simple percentage as well as inferential statistics tools of T-TEST and ANOVA. The findings revealed that there was a significant relationship existing among the main identified barriers (environmental barrier, communication barrier, hearing loss, unemployment and poor sexuality education) to the marital expectations of unmarried persons with hearing impairment. The joint contribution of the independent variables (identified barriers) to the dependent variable (marital expectations) was significant, F = 5.842, P < 0.05, accounting for about 89% of the variance. The relative contribution of the identified barriers to marital expectations of unmarried persons with hearing impairment is as follows: environmental barrier (β = 0.808, t = 5.176, P < 0.05), communication barrier (β = 0.533, t = 3.305, P < 0.05), hearing loss (β = 0.550, t = 2.233, P < 0.05), unemployment (β = 0.431, t = 2.102, P < 0.05), poor sexuality education (β = 0.361, t = 1.985, P < 0.05). Environmental barrier proved to be the most potent contributor to the poor marital expectations among unmarried persons with hearing impairment. Therefore, it is recommended that society dismantles the nagging environmental barrier through positive identification with individuals suffering from hearing impairment. In this connection, members of society should change their negative attitudes and do away with all the wrong notions about the marital ability of individuals with hearing impairment.

Keywords: environmental barrier, hearing impairment, marriage, marital expectations

Procedia PDF Downloads 363
5846 Cultural Stereotypes in EFL Classrooms and Their Implications on English Language Procedures in Cameroon

Authors: Eric Enongene Ekembe

Abstract:

Recent calls on EFL teaching posit the centrality of context factors and argue for a correlation between effectiveness in teaching with the learners’ culture in the EFL classroom. Context is not everything; it is defined with indicators of learners’ cultural artifacts and stereotypes in meaningful interactions in the language classroom. In keeping with this, it is difficult to universalise pedagogic procedures given that appropriate procedures are context-sensitive- and contexts differ. It is necessary to investigate what counts as cultural specificities or stereotypes of specific learners to reflect on how different language learning contexts affect or are affected by English language teaching procedures, most especially in under-represented cultures, which have appropriated the English language. This paper investigates cultural stereotypes of EFL learners in the culturally diverse Cameroon to examine how they mediate teaching and learning. Data collected on mixed-method basis from 83 EFL teachers and 1321 learners in Cameroon reveal a strong presence of typical cultural artifacts and stereotypes. Statistical analysis and thematic coding demonstrate that teaching procedures in place were insensitive to the cultural artifacts and stereotypes, resulting in trending tension between teachers and learners. The data equally reveal a serious contradiction between the communicative goals of language teaching and learning: what teachers held as effective teaching was diametrically opposed to success in learning. In keeping with this, the paper argues for a ‘decentred’ teacher preparation in Cameroon that is informed by systemic learners’ feedback. On this basis, applied linguistics has the urgent task of exploring dimensions of what actually counts as contextualized practice in ELT.

Keywords: cultural stereotypes, EFL, implications, procedures

Procedia PDF Downloads 122
5845 Change of Substrate in Solid State Fermentation Can Produce Proteases and Phytases with Extremely Distinct Biochemical Characteristics and Promising Applications for Animal Nutrition

Authors: Paula K. Novelli, Margarida M. Barros, Luciana F. Flueri

Abstract:

Utilization of agricultural by-products, wheat ban and soybean bran, as substrate for solid state fermentation (SSF) was studied, aiming the achievement of different enzymes from Aspergillus sp. with distinct biological characteristics and its application and improvement on animal nutrition. Aspergillus niger and Aspergillus oryzea were studied as they showed very high yield of phytase and protease production, respectively. Phytase activity was measure using p-nitrophenilphosphate as substrate and a standard curve of p-nitrophenol, as the enzymatic activity unit was the quantity of enzyme necessary to release one μmol of p-nitrophenol. Protease activity was measure using azocasein as substrate. Activity for phytase and protease substantially increased when the different biochemical characteristics were considered in the study. Optimum pH and stability of the phytase produced by A. niger with wheat bran as substrate was between 4.0 - 5.0 and optimum temperature of activity was 37oC. Phytase fermented in soybean bran showed constant values at all pHs studied, for optimal and stability, but low production. Phytase with both substrates showed stable activity for temperatures higher than 80oC. Protease from A. niger showed very distinct behavior of optimum pH, acid for wheat bran and basic for soybean bran, respectively and optimal values of temperature and stability at 50oC. Phytase produced by A. oryzae in wheat bran had optimum pH and temperature of 9 and 37oC, respectively, but it was very unstable. On the other hand, proteases were stable at high temperatures, all pH’s studied and showed very high yield when fermented in wheat bran, however when it was fermented in soybean bran the production was very low. Subsequently the upscale production of phytase from A. niger and proteases from A. oryzae were applied as an enzyme additive in fish fed for digestibility studies. Phytases and proteases were produced with stable enzyme activity of 7,000 U.g-1 and 2,500 U.g-1, respectively. When those enzymes were applied in a plant protein based fish diet for digestibility studies, they increased protein, mineral, energy and lipids availability, showing that these new enzymes can improve animal production and performance. In conclusion, the substrate, as well as, the microorganism species can affect the biochemical character of the enzyme produced. Moreover, the production of these enzymes by SSF can be up to 90% cheaper than commercial ones produced with the same fungi species but submerged fermentation. Add to that these cheap enzymes can be easily applied as animal diet additives to improve production and performance.

Keywords: agricultural by-products, animal nutrition, enzymes production, solid state fermentation

Procedia PDF Downloads 321
5844 Qualitative Inquiry on Existential Concerns and Well-Being among the Youth of Higher Education Institutions in Ethiopia: Case Study of Addis Ababa University

Authors: Ezgiamn Abraha Hagos

Abstract:

Higher education is important for college students to develop their authentic identity by means of getting exposure to diverse ideas and experiences. However, current college students are not successfully achieving a satisfying sense of meaning and purpose in their lives, which often places them in a state of existential vacuum. Thus, this study uncovers the existential concerns of youth in higher education by means of assessing their view on meaningful life and integration of it as a guide into their lives and challenges faced in doing so. Data were procured from thirty undergraduate students of Addis Ababa University, Ethiopia via interview, naïve sketch method, and content analysis of selected magazines and newspapers. Data were analyzed using organization, immersion, generating themes, coding, offering interpretation as well as checking the data. Relationship, education, and belief were found to be main sources of meaning. But, many of the study participants failed to articulate their meaning in life explicitly and identified to be in a state of drifting. Moreover, hopelessness, economic problems and quality of training impinge their sense of meaning in life negatively. The content analysis principally embodied the youth in higher education as a group of people confronted with rafts of challenges such as debauchery, moral crisis, self-destructive behaviors and hankering for support and direction. Thus, crafting the asset-based approach and counseling services that will prepare the youth for the future and develop holistically in terms of body and mind are tremendously vital.

Keywords: higher education institutions; meaning in life; youth

Procedia PDF Downloads 102
5843 Adaptive Motion Compensated Spatial Temporal Filter of Colonoscopy Video

Authors: Nidhal Azawi

Abstract:

Colonoscopy procedure is widely used in the world to detect an abnormality. Early diagnosis can help to heal many patients. Because of the unavoidable artifacts that exist in colon images, doctors cannot detect a colon surface precisely. The purpose of this work is to improve the visual quality of colonoscopy videos to provide better information for physicians by removing some artifacts. This work complements a series of work consisting of three previously published papers. In this paper, Optic flow is used for motion compensation, and then consecutive images are aligned/registered to integrate some information to create a new image that has or reveals more information than the original one. Colon images have been classified into informative and noninformative images by using a deep neural network. Then, two different strategies were used to treat informative and noninformative images. Informative images were treated by using Lucas Kanade (LK) with an adaptive temporal mean/median filter, whereas noninformative images are treated by using Lucas Kanade with a derivative of Gaussian (LKDOG) with adaptive temporal median images. A comparison result showed that this work achieved better results than that results in the state- of- the- art strategies for the same degraded colon images data set, which consists of 1000 images. The new proposed algorithm reduced the error alignment by about a factor of 0.3 with a 100% successfully image alignment ratio. In conclusion, this algorithm achieved better results than the state-of-the-art approaches in case of enhancing the informative images as shown in the results section; also, it succeeded to convert the non-informative images that have very few details/no details because of the blurriness/out of focus or because of the specular highlight dominate significant amount of an image to informative images.

Keywords: optic flow, colonoscopy, artifacts, spatial temporal filter

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5842 Spectroscopic Study of Tb³⁺ Doped Calcium Aluminozincate Phosphor for Display and Solid-State Lighting Applications

Authors: Sumandeep Kaur, Allam Srinivasa Rao, Mula Jayasimhadri

Abstract:

In recent years, rare earth (RE) ions doped inorganic luminescent materials are seeking great attention due to their excellent physical and chemical properties. These materials offer high thermal and chemical stability and exhibit good luminescence properties due to the presence of RE ions. The luminescent properties of these materials are attributed to their intra-configurational f-f transitions in RE ions. A series of Tb³⁺ doped calcium aluminozincate has been synthesized via sol-gel method. The structural and morphological studies have been carried out by recording X-ray diffraction patterns and SEM image. The luminescent spectra have been recorded for a comprehensive study of their luminescence properties. The XRD profile reveals the single-phase orthorhombic crystal structure with an average crystallite size of 65 nm as calculated by using DebyeScherrer equation. The SEM image exhibits completely random, irregular morphology of micron size particles of the prepared samples. The optimization of luminescence has been carried out by varying the dopant Tb³⁺ concentration within the range from 0.5 to 2.0 mol%. The as-synthesized phosphors exhibit intense emission at 544 nm pumped at 478 nm excitation wavelength. The optimized Tb³⁺ concentration has been found to be 1.0 mol% in the present host lattice. The decay curves show bi-exponential fitting for the as-synthesized phosphor. The colorimetric studies show green emission with CIE coordinates (0.334, 0.647) lying in green region for the optimized Tb³⁺ concentration. This report reveals the potential utility of Tb³⁺ doped calcium aluminozincate phosphors for display and solid-state lighting devices.

Keywords: concentration quenching, phosphor, photoluminescence, XRD

Procedia PDF Downloads 145
5841 Marosok Tradition in the Process of Buying and Selling Cattle in Payakumbuh: A Comparative Study between Adat Law and Positive Law of Indonesia

Authors: Mhd. Zakiul Fikri, M. Agus Maulidi

Abstract:

Indonesia is a constitutional state. As the constitutional state, Indonesia is not only using a single legal system, but also adopting three legal systems consist of: The European continental legal system or positive law of Indonesia, adat law system, and legal system of religion. This study will discuss Marosok tradition in the process of buying and selling cattle in Payakumbuh: a comparative study between adat law and positive law of Indonesia. The objectives of this research are: First, to find the meaning of the philosophical of Marosok tradition in Payakumbuh. Second, to find the legal implications of the Marosok tradition reviewed aspects of adat law and positive law of Indonesia. Third, to find legal procedure in arbitrating the dispute wich is potentially appear in the post-process of buying and selling cattle based on positive law and adat law adopted in Indonesia. This research is empirical legal research that using two model approaches which are statute approach and conceptual approach. Data was obtained through interviews, observations, and documents or books. Then a method of data analysis used is inductive analysis. Finally, this study found that: First, tradition of Marosok contains the meaning of harmonization of social life that keep people from negative debate, envy, and arrogant. Second, Marosok tradition is one of the adat law in Indonesia; it is one of contract law in the process of buying and selling. If the comparison between the practice Marosok tradition as adat law with the provisions of Article 1320 book of civil code about the terms of the validity of a contract, the elements contained in the provisions of these regulations are met in practice Marosok. Thus, the practice of Marosok in buying and selling cattle process in Payakumbuh justified in view of the positive law of Indonesia. Last of all, all kinds of disputes arising due to contracts made by Marosok tradition can be resolved by positive law and adat law of Indonesia.

Keywords: Adat law, contract, Indonesia, Marosok

Procedia PDF Downloads 315
5840 A Case Study on Post-Occupancy Evaluation of User Satisfaction in Higher Educational Buildings

Authors: Yuanhong Zhao, Qingping Yang, Andrew Fox, Tao Zhang

Abstract:

Post-occupancy evaluation (POE) is a systematic approach to assess the actual building performance after the building has been occupied for some time. In this paper, a structured POE assessment was conducted using the building use survey (BUS) methodology in two higher educational buildings in the United Kingdom. This study aims to help close the building performance gap, provide optimized building operation suggestions, and to improve occupants’ satisfaction level. In this research, the questionnaire survey investigated the influences of environmental factors on user satisfaction from the main aspects of building overall design, thermal comfort, perceived control, indoor environment quality for noise, lighting, ventilation, and other non-environmental factors, such as the background information about age, sex, time in buildings, workgroup size, and so on. The results indicate that the occupant satisfaction level with the main aspects of building overall design, indoor environment quality, and thermal comfort in summer and winter on both two buildings, which is lower than the benchmark data. The feedback of this POE assessment has been reported to the building management team to allow managers to develop high-performance building operation plans. Finally, this research provided improvement suggestions to the building operation system to narrow down the performance gap and improve the user work experience satisfaction and productivity level.

Keywords: building performance assessment systems, higher educational buildings, post-occupancy evaluation, user satisfaction

Procedia PDF Downloads 148
5839 Excited State Structural Dynamics of Retinal Isomerization Revealed by a Femtosecond X-Ray Laser

Authors: Przemyslaw Nogly, Tobias Weinert, Daniel James, Sergio Carbajo, Dmitry Ozerov, Antonia Furrer, Dardan Gashi, Veniamin Borin, Petr Skopintsev, Kathrin Jaeger, Karol Nass, Petra Bath, Robert Bosman, Jason Koglin, Matthew Seaberg, Thomas Lane, Demet Kekilli, Steffen Brünle, Tomoyuki Tanaka, Wenting Wu, Christopher Milne, Thomas A. White, Anton Barty, Uwe Weierstall, Valerie Panneels, Eriko Nango, So Iwata, Mark Hunter, Igor Schapiro, Gebhard Schertler, Richard Neutze, Jörg Standfuss

Abstract:

Ultrafast isomerization of retinal is the primary step in a range of photoresponsive biological functions including vision in humans and ion-transport across bacterial membranes. We studied the sub-picosecond structural dynamics of retinal isomerization in the light-driven proton pump bacteriorhodopsin using an X-ray laser. Twenty snapshots with near-atomic spatial and temporal resolution in the femtosecond regime show how the excited all-trans retinal samples conformational states within the protein binding pocket prior to passing through a highly-twisted geometry and emerging in the 13-cis conformation. The aspartic acid residues and functional water molecules in proximity of the retinal Schiff base respond collectively to formation and decay of the initial excited state and retinal isomerization. These observations reveal how the protein scaffold guides this remarkably efficient photochemical reaction.

Keywords: bacteriorhodopsin, free-electron laser, retinal isomerization mechanism, time-resolved crystallography

Procedia PDF Downloads 240