Search results for: parallel job shop scheduling problem
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8461

Search results for: parallel job shop scheduling problem

5761 The Effect of Midwifery Counseling Based on Gamble Approach on the Coping Strategies of Women with Abortion: A Randomized Controlled Clinical Trial

Authors: Hasanzadeh Tahraband F., Kheirkhah M.

Abstract:

The trauma resulting from abortion causes fear, frustration, inability, lack of self-confidence, and psychological distress in women. The present study was conducted to determine the effect of midwifery counseling based on the Gamble approach on coping strategies of women with abortion. This randomized controlled clinical trial was conducted on women with abortions in April–October 2021, Karaj, Iran. Ninety-six eligible women were randomly assigned to two 48-member groups with 4, 6, and 8 blocks. The women in the intervention group participated in two 45-75-minute Gamble counseling programs. They were asked to fill out the demographic and fertility information questionnaire before the intervention and the cope operations preference inquiry questionnaire before, immediately (in the 4-6th week of the study), and three months after the intervention. The analysis of the data was done through Chi-square, independent sample t-test. The significance level was considered P<0.05. The results showed that the differences between the two groups before the intervention were not statistically significant in terms of demographic and fertility variables (P>0.05). However, the total mean score of the problem-focused dimension in 3-month post-abortion (97/34±8/69) and the emotion-focused dimension in 4-6 weeks and 3-month post-abortion (34/14±3/48 and 32/41±3/41) in the intervention group was significantly different from the control group (P<0.001). According to the results of the repeated measures ANOVA, the level of coping and its dimensions significantly changed in the intervention group over time (P<0.001). The results of the present study showed that Gamble counseling promoted the problem-focused dimension score and reduced the emotion-focused dimension score in women with abortion. It is recommended that Gamble counseling should be used as midwife-led counseling to increase coping strategies and reduce the psychological distress of women who have experienced abortion.

Keywords: midwife-led counseling, coping strategies, post-abortion, psychological distress, Iran

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5760 Design and Thermal Analysis of Power Harvesting System of a Hexagonal Shaped Small Spacecraft

Authors: Mansa Radhakrishnan, Anwar Ali, Muhammad Rizwan Mughal

Abstract:

Many universities around the world are working on modular and low budget architecture of small spacecraft to reduce the development cost of the overall system. This paper focuses on the design of a modular solar power harvesting system for a hexagonal-shaped small satellite. The designed solar power harvesting systems are composed of solar panels and power converter subsystems. The solar panel is composed of solar cells mounted on the external face of the printed circuit board (PCB), while the electronic components of power conversion are mounted on the interior side of the same PCB. The solar panel with dimensions 16.5cm × 99cm is composed of 36 solar cells (each solar cell is 4cm × 7cm) divided into four parallel banks where each bank consists of 9 solar cells. The output voltage of a single solar cell is 2.14V, and the combined output voltage of 9 series connected solar cells is around 19.3V. The output voltage of the solar panel is boosted to the satellite power distribution bus voltage level (28V) by a boost converter working on a constant voltage maximum power point tracking (MPPT) technique. The solar panel module is an eight-layer PCB having embedded coil in 4 internal layers. This coil is used to control the attitude of the spacecraft, which consumes power to generate a magnetic field and rotate the spacecraft. As power converter and distribution subsystem components are mounted on the PCB internal layer, therefore it is mandatory to do thermal analysis in order to ensure that the overall module temperature is within thermal safety limits. The main focus of the overall design is on compactness, miniaturization, and efficiency enhancement.

Keywords: small satellites, power subsystem, efficiency, MPPT

Procedia PDF Downloads 56
5759 Experimental Investigations on the Mechanical properties of Spiny (Kawayan Tinik) Bamboo Layers

Authors: Ma. Doreen E. Candelaria, Ma. Louise Margaret A. Ramos, Dr. Jaime Y. Hernandez, Jr

Abstract:

Bamboo has been introduced as a possible alternative to some construction materials nowadays. Its potential use in the field of engineering, however, is still not widely practiced due to insufficient engineering knowledge on the material’s properties and characteristics. Although there are researches and studies proving its advantages, it is still not enough to say that bamboo can sustain and provide the strength and capacity required of common structures. In line with this, a more detailed analysis was made to observe the layered structure of the bamboo, particularly the species of Kawayan Tinik. It is the main intent of this research to provide the necessary experiments to determine the tensile strength of dried bamboo samples. The test includes tensile strength parallel to fibers with samples taken at internodes only. Throughout the experiment, methods suggested by the International Organization for Standardization (ISO) were followed. The specimens were tested using 3366 INSTRON Universal Testing Machine, with a rate of loading set to 0.6 mm/min. It was then observed from the results of these experiments that dried bamboo samples recorded high layered tensile strengths, as high as 600 MPa. Likewise, along the culm’s length and across its cross section, higher tensile strength were observed at the top part and at its outer layers. Overall, the top part recorded the highest tensile strength per layer, with its outer layers having tensile strength as high as 600 MPa. The recorded tensile strength of its middle and inner layers, on the other hand, were approximately 450 MPa and 180 MPa, respectively. From this variation in tensile strength across the cross section, it may be concluded that an increase in tensile strength may be observed towards the outer periphery of the bamboo. With these preliminary investigations on the layered tensile strength of bamboo, it is highly recommended to conduct experimental investigations on the layered compressive strength properties as well. It is also suggested to conduct investigations evaluating perpendicular layered tensile strength of the material.

Keywords: bamboo strength, layered strength tests, strength test, tensile test

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5758 Ant System with Acoustic Communication

Authors: Saad Bougrine, Salma Ouchraa, Belaid Ahiod, Abdelhakim Ameur El Imrani

Abstract:

Ant colony optimization is an ant algorithm framework that took inspiration from foraging behaviour of ant colonies. Indeed, ACO algorithms use a chemical communication, represented by pheromone trails, to build good solutions. However, ants involve different communication channels to interact. Thus, this paper introduces the acoustic communication between ants while they are foraging. This process allows fine and local exploration of search space and permits optimal solution to be improved.

Keywords: acoustic communication, ant colony optimization, local search, traveling salesman problem

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5757 A New Realization of Multidimensional System for Grid Sensor Network

Authors: Yang Xiong, Hua Cheng

Abstract:

In this paper, for the basic problem of wireless sensor network topology control and deployment, the Roesser model in rectangular grid sensor networks is presented. In addition, a general constructive realization procedure will be proposed. The procedure enables a distributed implementation of linear systems on a sensor network. A non-trivial example is illustrated.

Keywords: grid sensor networks, Roesser model, state-space realization, multidimensional systems

Procedia PDF Downloads 641
5756 Experimental Research on Neck Thinning Dynamics of Droplets in Cross Junction Microchannels

Authors: Yilin Ma, Zhaomiao Liu, Xiang Wang, Yan Pang

Abstract:

Microscale droplets play an increasingly important role in various applications, including medical diagnostics, material synthesis, chemical engineering, and cell research due to features of high surface-to-volume ratio and tiny scale, which can significantly improve reaction rates, enhance heat transfer efficiency, enable high-throughput parallel studies as well as reduce reagent usage. As a mature technique to manipulate small amounts of liquids, droplet microfluidics could achieve the precise control of droplet parameters such as size, uniformity, structure, and thus has been widely adopted in the engineering and scientific research of multiple fields. Necking processes of the droplet in the cross junction microchannels are experimentally and theoretically investigated and dynamic mechanisms of the neck thinning in two different regimes are revealed. According to evolutions of the minimum neck width and the thinning rate, the necking process is further divided into different stages and the main driving force during each stage is confirmed. Effects of the flow rates and the cross-sectional aspect ratio on the necking process as well as the neck profile at different stages are provided in detail. The distinct features of the two regimes in the squeezing stage are well captured by the theoretical estimations of the effective flow rate and the variations of the actual flow rates in different channels are reasonably reflected by the channel width ratio. In the collapsing stage, the quantitative relation between the minimum neck width and the remaining time is constructed to identify the physical mechanism.

Keywords: cross junction, neck thinning, force analysis, inertial mechanism

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5755 A Comprehensive Approach to Create ‘Livable Streets’ in the Mixed Land Use of Urban Neighborhoods: A Case Study of Bangalore Street

Authors: K. C. Tanuja, Mamatha P. Raj

Abstract:

"People have always lived on streets. They have been the places where children first learned about the world, where neighbours met, the social centres of towns and cities, the rallying points for revolts, the scenes of repression. The street has always been the scene of this conflict, between living and access, between resident and traveller, between street life and the threat of death.” Livable Streets by Donald Appleyard. Urbanisation is happening rapidly all over the world. As population increasing in the urban settlements, its required to provide quality of life to all the inhabitants who live in. Urban design is a place making strategic planning. Urban design principles promote visualising any place environmentally, socially and economically viable. Urban design strategies include building mass, transit development, economic viability and sustenance and social aspects. Cities are wonderful inventions of diversity- People, things, activities, ideas and ideologies. Cities should be smarter and adjustable to present technology and intelligent system. Streets represent the community in terms of social and physical aspects. Streets are an urban form that responds to many issues and are central to urban life. Streets are for livability, safety, mobility, place of interest, economic opportunity, balancing the ecology and for mass transit. Urban streets are places where people walk, shop, meet and engage in different types of social and recreational activities which make urban community enjoyable. Streets knit the urban fabric of activities. Urban streets become livable with the introduction of social network enhancing the pedestrian character by providing good design features which in turn should achieve the minimal impact of motor vehicle use on pedestrians. Livable streets are the spatial definition to the public right of way on urban streets. Streets in India have traditionally been the public spaces where social life happened or created from ages. Streets constitute the urban public realm where people congregate, celebrate and interact. Streets are public places that can promote social interaction, active living and community identity. Streets as potential contributors to a better living environment, knitting together the urban fabric of people and places that make up a community. Livable streets or complete streets are making our streets as social places, roadways and sidewalks accessible, safe, efficient and useable for all people. The purpose of this paper is to understand the concept of livable street and parameters of livability on urban streets. Streets to be designed as the pedestrians are the main users and create spaces and furniture for social interaction which serves for the needs of the people of all ages and abilities. The problems of streets like congestion due to width of the street, traffic movement and adjacent land use and type of movement need to be redesigned and improve conditions defining the clear movement path for vehicles and pedestrians. Well-designed spatial qualities of street enhances the street environment, livability and then achieves quality of life to the pedestrians. A methodology been derived to arrive at the typologies in street design after analysis of existing situation and comparing with livable standards. It was Donald Appleyard‟s Livable Streets laid out the social effects on streets creating the social network to achieve Livable Streets.

Keywords: livable streets, social interaction, pedestrian use, urban design

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5754 Relative Entropy Used to Determine the Divergence of Cells in Single Cell RNA Sequence Data Analysis

Authors: An Chengrui, Yin Zi, Wu Bingbing, Ma Yuanzhu, Jin Kaixiu, Chen Xiao, Ouyang Hongwei

Abstract:

Single cell RNA sequence (scRNA-seq) is one of the effective tools to study transcriptomics of biological processes. Recently, similarity measurement of cells is Euclidian distance or its derivatives. However, the process of scRNA-seq is a multi-variate Bernoulli event model, thus we hypothesize that it would be more efficient when the divergence between cells is valued with relative entropy than Euclidian distance. In this study, we compared the performances of Euclidian distance, Spearman correlation distance and Relative Entropy using scRNA-seq data of the early, medial and late stage of limb development generated in our lab. Relative Entropy is better than other methods according to cluster potential test. Furthermore, we developed KL-SNE, an algorithm modifying t-SNE whose definition of divergence between cells Euclidian distance to Kullback–Leibler divergence. Results showed that KL-SNE was more effective to dissect cell heterogeneity than t-SNE, indicating the better performance of relative entropy than Euclidian distance. Specifically, the chondrocyte expressing Comp was clustered together with KL-SNE but not with t-SNE. Surprisingly, cells in early stage were surrounded by cells in medial stage in the processing of KL-SNE while medial cells neighbored to late stage with the process of t-SNE. This results parallel to Heatmap which showed cells in medial stage were more heterogenic than cells in other stages. In addition, we also found that results of KL-SNE tend to follow Gaussian distribution compared with those of the t-SNE, which could also be verified with the analysis of scRNA-seq data from another study on human embryo development. Therefore, it is also an effective way to convert non-Gaussian distribution to Gaussian distribution and facilitate the subsequent statistic possesses. Thus, relative entropy is potentially a better way to determine the divergence of cells in scRNA-seq data analysis.

Keywords: Single cell RNA sequence, Similarity measurement, Relative Entropy, KL-SNE, t-SNE

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5753 Contribution to Improving the DFIG Control Using a Multi-Level Inverter

Authors: Imane El Karaoui, Mohammed Maaroufi, Hamid Chaikhy

Abstract:

Doubly Fed Induction Generator (DFIG) is one of the most reliable wind generator. Major problem in wind power generation is to generate Sinusoidal signal with very low THD on variable speed caused by inverter two levels used. This paper presents a multi-level inverter whose objective is to reduce the THD and the dimensions of the output filter. This work proposes a three-level NPC-type inverter, the results simulation are presented demonstrating the efficiency of the proposed inverter.

Keywords: DFIG, multilevel inverter, NPC inverter, THD, induction machine

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5752 Information and Communication Technology (ICT) Education Improvement for Enhancing Learning Performance and Social Equality

Authors: Heichia Wang, Yalan Chao

Abstract:

Social inequality is a persistent problem. One of the ways to solve this problem is through education. At present, vulnerable groups are often less geographically accessible to educational resources. However, compared with educational resources, communication equipment is easier for vulnerable groups. Now that information and communication technology (ICT) has entered the field of education, today we can accept the convenience that ICT provides in education, and the mobility that it brings makes learning independent of time and place. With mobile learning, teachers and students can start discussions in an online chat room without the limitations of time or place. However, because liquidity learning is quite convenient, people tend to solve problems in short online texts with lack of detailed information in a lack of convenient online environment to express ideas. Therefore, the ICT education environment may cause misunderstanding between teachers and students. Therefore, in order to better understand each other's views between teachers and students, this study aims to clarify the essays of the analysts and classify the students into several types of learning questions to clarify the views of teachers and students. In addition, this study attempts to extend the description of possible omissions in short texts by using external resources prior to classification. In short, by applying a short text classification, this study can point out each student's learning problems and inform the instructor where the main focus of the future course is, thus improving the ICT education environment. In order to achieve the goals, this research uses convolutional neural network (CNN) method to analyze short discussion content between teachers and students in an ICT education environment. Divide students into several main types of learning problem groups to facilitate answering student problems. In addition, this study will further cluster sub-categories of each major learning type to indicate specific problems for each student. Unlike most neural network programs, this study attempts to extend short texts with external resources before classifying them to improve classification performance. In short, by applying the classification of short texts, we can point out the learning problems of each student and inform the instructors where the main focus of future courses will improve the ICT education environment. The data of the empirical process will be used to pre-process the chat records between teachers and students and the course materials. An action system will be set up to compare the most similar parts of the teaching material with each student's chat history to improve future classification performance. Later, the function of short text classification uses CNN to classify rich chat records into several major learning problems based on theory-driven titles. By applying these modules, this research hopes to clarify the main learning problems of students and inform teachers that they should focus on future teaching.

Keywords: ICT education improvement, social equality, short text analysis, convolutional neural network

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5751 Epidemiology of Private Prehospital Calls over the Last Decade in South Africa

Authors: Rhodine Hickman, Craig Wylie, Michael G. McCaul

Abstract:

Introduction: The World Health Organisation has called on governments around the world to recognise emergency conditions as a global public health problem and respond with appropriate steps for effective preventative strategies. However, to understand the magnitude of the problem, good quality epidemiological data is required. This is especially challenging in low and middle-income countries, where routine data is scarce, specifically within the prehospital setting. Methods: We conducted a retrospective cross-sectional study of a national prehospital private sector EMS database. The database being the property of ER24 (private Emergency Medical Services (EMS) company in South Africa) contains claims submitted by the majority of ambulance services in South Africa during the period between 1 January 2008 to 28 March 2017. We used descriptive statistics and control charts to describe the data using STATA 14. Results: 299,257 calls were included in the analysis. The top clinical conditions requiring ambulance transport were transport accidents (10% of total call volume) and ischaemic heart disease (4.4%). The number of transport accidents consistently increased between 2009 and 2014 and reached beyond the limit for normal variation in 2015. Victims of transport accidents required basic life support services 60% of the time with 80% of injuries being minor to moderate. The frequency of ischaemic heart disease had a steady incline from 2011 to 2016. Advanced life support services were required about 50% of the time, with 60% of patients needing urgent care. Conclusion: Transport accidents, followed by ischaemic heart disease, are the most prevalent conditions in South African private EMS. There is a potential to address these conditions by developing the capacity of low and mid-level providers in trauma and advanced EMS providers in ischaemic heart disease.

Keywords: emergency care, emergency medicine, prehospital providers, South Africa

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5750 Effect of Strains and Temperature on the Twinning Behavior of High Purity Titanium Compressed by Split Hopkinson Pressure Bar

Authors: Ping Zhou, Dawu Xiao, Chunli Jiang, Ge Sang

Abstract:

Deformation twinning plays an important role in the mechanical properties of Ti which has high specific strength and excellent corrosion resistance ability. To investigate the twinning behavior of Ti under high strain rate compression, the split Hopkinson pressure bar (SHPB) was adopted to deform samples to different strains at room temperature. In addition, twinning behaviors under varied temperatures of 373K, 573K and 873K were also investigated. The cylindrical-shaped samples with purity 99.995% were annealed at 1073K for 1 hour in vacuum before compression. All the deformation twins were identified by electron backscatter diffraction (EBSD) techniques. The mechanical behavior showed three-stage work hardening in stress-strain curves for samples deformed at temperature 573K and 873K, while only two stages were observed for those deformed at room temperature. For samples compressed at room temperature, the predominant twin types are {10-12}<10-11> (E1), {11-21}<11-26> (E2) and {11-21}<11-23> (C1). The secondary and tertiary twinning was observed inside some E1, E2 and C1 twins. Most of the twin boundaries of E2 acted as the nucleate sites of E1. The densities of twins increase remarkably with increment of strains. For samples compressed at relatively higher temperatures, the migration of twin boundaries of E1, E2 and C1 was observed. All the twin lamellas shorten with temperature, and nearly disappeared at 873K except some remaining E1 twins. Polygonizations of grain boundaries were observed above 573K. The microstructure intended to have a texture with c-axes parallel to compression direction with temperature increment. Factors affecting the dynamic recovery and re-crystallization were discussed.

Keywords: deformation twins, EBSD, mechanical behavior, high strain rate, titanium

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5749 Field Theories in Chiral Liquid Crystals: A Theory for Helicoids and Skyrmions

Authors: G. De Matteis, L. Martina, V. Turco

Abstract:

The work is focused on determining and comparing special nonlinear static configurations in cholesteric liquid crystals (CLCs), confined between two parallel plates and in the presence of an external static electric/magnetic field. The solutions are stabilised by topological and non-topological conservation laws since they are described in terms of integrable or partially integrable nonlinear boundary value problems. In cholesteric liquid crystals which are subject to geometric frustration; anchoring conditions at boundaries, i.e., homeotropic conditions, are incompatible with the cholesteric twist. This aspect turns out to be essential in the admissible classes of solutions, allowing also for disclination type singularities. Within the framework of Frank-Oseen theory, we study the static configurations for CLCs. First, we find numerical solutions for isolated axisymmetric states in confined CLCs with weak homeotropic anchoring at the boundaries. These solutions describe 3-dimensional modulations, namely spherulites or cholesteric bubbles, actually observed in these systems, of standard baby skyrmions. Relations with well-known nonlinear integrable systems are found and are used to explore the asymptotic behavior of the solutions. Then we turn our attention to extended periodic static configurations called Helicoids or cholesteric fingers, described by an elliptic sine-Gordon model with appropriate boundary conditions, showing how their period and energies are determined by both the thickness of the cell and the intensity of the external electric/magnetic field. We explicitly show that helicoids with π or 2π of rotations of the molecular director are different in many aspects and are not simply algebraically related. The behaviour of the solutions, their energy and the properties of the associated disclinations are discussed in detail, both analytically and numerically.

Keywords: cholesteric liquid crystals, geometric frustration, helicoids, skyrmions

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5748 Time-Dependent Modulation on Depressive Responses and Circadian Rhythms of Corticosterone in Models of Melatonin Deficit

Authors: Jana Tchekalarova, Milena Atanasova, Katerina Georgieva

Abstract:

Melatonin deficit can cause a disturbance in emotional status and circadian rhythms of the endocrine system in the body. Both pharmacological and alternative approaches are applied for correction of dysfunctions driven by changes in circadian dynamics of many physiological indicators. In the present study, we tested and compare the beneficial effect of agomelatine (40 mg/kg, i.p. for 3 weeks) and endurance training on depressive behavior in two models of melatonin deficit in rat. The role of disturbed circadian rhythms of plasma melatonin and corticosterone secretion in the mechanism of these treatments was also explored. The continuous exercise program attenuated depressive responses associated with disrupted diurnal rhythm of home-cage motor activity, anhedonia in the sucrose preference test, and despair-like behavior in the forced swimming test were attenuated by agomelatine exposed to chronic constant light (CCL) and long-term exercise in pinealectomized rats. Parallel to the observed positive effect on the emotional status, agomelatine restored CCL-induced impairment of circadian patterns of plasma melatonin but not that of corticosterone. In opposite, exercise training diminished total plasma corticosterone levels and corrected its flattened pattern while it was unable to correct melatonin deficit in pinealectomy. These results suggest that the antidepressant-like effect of pharmacological and alternative approach might be mediated via two different mechanism, correction of the disturbed circadian rhythm of melatonin and corticosterone, respectively. Therefore, these treatment approaches might have a potential therapeutic application in different subpopulations of people characterized by a melatonin deficiency. This work was supported by the National Science Fund of Bulgaria (research grant # № DN 03/10; DN# 12/6).

Keywords: agomelatine, exercise training, melatonin deficit, corticosterone

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5747 Measuring Fundamental Growth Needs in a Youth Boatbuilding Context

Authors: Shane Theunissen, Rob Grandy

Abstract:

Historically and we would fairly conventionally within our formal schooling systems, we have convergent testing where all the students are expected to converge on the same answer, and that answer has been determined by an external authority that is reproducing knowledge of the hegemon. Many youths may not embody the cultural capital that's rewarded in formal schooling contexts as they aren't able to converge on the required answer that's being determined by the classroom teacher or the administrators. In this paper, we explore divergent processes that promote creative problem-solving. We embody this divergent process in our measurement of fundamental growth needs. To this end, we utilize the Mosaic Approach as a method for implementing the Outcomes That Matter framework. Outcomes That Matter is the name of the measurement tool built around the Circle of Courage framework, which is a way of identifying fundamental growth needs for young people. The Circle of Courage was developed by Martin-Broken-Leg and colleagues as a way to connect indigenous child-rearing philosophies with contemporary resilience and positive psychology research. The Outcomes that Matter framework puts forward four categories of growth needs for young people. These are: Belonging, which on a macro scale is acceptance into the greater community of practice, Mastery which includes a constellation of concepts including confidence, motivation, self-actualization, and self-determination, Independence refers to a sense of personal power into autonomy within a context where creativity and problem solving, and a personal voice can begin to emerge, and finally Generosity which includes interpersonal things like conflict resolution and teamwork. Outcomes of Matter puts these four domains into a measurement tool that facilitates collaborative assessment between the youth, teachers, and recreation therapists that allows for youth-led narratives pertaining to their fundamental growth outcomes. This application of the Outcomes That Matter framework is unique as it may be the first application of this framework in an educational boatbuilding context.

Keywords: collaboration, empowerment, outcomes that matter, mosaic approach, boat building

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5746 An Industrial Steady State Sequence Disorder Model for Flow Controlled Multi-Input Single-Output Queues in Manufacturing Systems

Authors: Anthony John Walker, Glen Bright

Abstract:

The challenge faced by manufactures, when producing custom products, is that each product needs exact components. This can cause work-in-process instability due to component matching constraints imposed on assembly cells. Clearing type flow control policies have been used extensively in mediating server access between multiple arrival processes. Although the stability and performance of clearing policies has been well formulated and studied in the literature, the growth in arrival to departure sequence disorder for each arriving job, across a serving resource, is still an area for further analysis. In this paper, a closed form industrial model has been formulated that characterizes arrival-to-departure sequence disorder through stable manufacturing systems under clearing type flow control policy. Specifically addressed are the effects of sequence disorder imposed on a downstream assembly cell in terms of work-in-process instability induced through component matching constraints. Results from a simulated manufacturing system show that steady state average sequence disorder in parallel upstream processing cells can be balanced in order to decrease downstream assembly system instability. Simulation results also show that the closed form model accurately describes the growth and limiting behavior of average sequence disorder between parts arriving and departing from a manufacturing system flow controlled via clearing policy.

Keywords: assembly system constraint, custom products, discrete sequence disorder, flow control

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5745 Characterization of Hyaluronic Acid-Based Injections Used on Rejuvenation Skin Treatments

Authors: Lucas Kurth de Azambuja, Loise Silveira da Silva, Gean Vitor Salmoria, Darlan Dallacosta, Carlos Rodrigo de Mello Roesler

Abstract:

This work provides a physicochemical and thermal characterization assessment of three different hyaluronic acid (HA)-based injections used for rejuvenation skin treatments. The three products analyzed are manufactured by the same manufacturer and commercialized for application on different skin levels. According to the manufacturer, all three HA-based injections are crosslinked and have a concentration of 23 mg/mL of HA, and 0.3% of lidocaine. Samples were characterized by Fourier-transformed infrared (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscope (SEM) techniques. FTIR analysis resulted in a similar spectrum when comparing the different products. DSC analysis demonstrated that the fusion points differ in each product, with a higher fusion temperature observed in specimen A, which is used for subcutaneous applications, when compared with B and C, which are used for the middle dermis and deep dermis, respectively. TGA data demonstrated a considerable mass loss at 100°C, which means that the product has more than 50% of water in its composition. TGA analysis also showed that Specimen A had a lower mass loss at 100°C when compared to Specimen C. A mass loss of around 220°C was observed on all samples, characterizing the presence of hyaluronic acid. SEM images displayed a similar structure on all samples analyzed, with a thicker layer for Specimen A when compared with B and C. This series of analyses demonstrated that, as expected, the physicochemical and thermal properties of the products differ according to their application. Furthermore, to better characterize the crosslinking degree of each product and their mechanical properties, a set of different techniques should be applied in parallel to correlate the results and, thereby, relate injection application with material properties.

Keywords: hyaluronic acid, characterization, soft-tissue fillers, injectable gels

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5744 Comparison of FNTD and OSLD Detectors' Responses to Light Ion Beams Using Monte Carlo Simulations and Exprimental Data

Authors: M. R. Akbari, H. Yousefnia, A. Ghasemi

Abstract:

Al2O3:C,Mg fluorescent nuclear track detector (FNTD) and Al2O3:C optically stimulated luminescence detector (OSLD) are becoming two of the applied detectors in ion dosimetry. Therefore, the response of these detectors to hadron beams is highly of interest in radiation therapy (RT) using ion beams. In this study, these detectors' responses to proton and Helium-4 ion beams were compared using Monte Carlo simulations. The calculated data for proton beams were compared with Markus ionization chamber (IC) measurement (in water phantom) from M.D. Anderson proton therapy center. Monte Carlo simulations were performed via the FLUKA code (version 2011.2-17). The detectors were modeled in cylindrical shape at various depths of the water phantom without shading each other for obtaining relative depth dose in the phantom. Mono-energetic parallel ion beams in different incident energies (100 MeV/n to 250 MeV/n) were collided perpendicularly on the phantom surface. For proton beams, the results showed that the simulated detectors have over response relative to IC measurements in water phantom. In all cases, there were good agreements between simulated ion ranges in the water with calculated and experimental results reported by the literature. For proton, maximum peak to entrance dose ratio in the simulated water phantom was 4.3 compared with about 3 obtained from IC measurements. For He-4 ion beams, maximum peak to entrance ratio calculated by both detectors was less than 3.6 in all energies. Generally, it can be said that FLUKA is a good tool to calculate Al2O3:C,Mg FNTD and Al2O3:C OSLD detectors responses to therapeutic proton and He-4 ion beams. It can also calculate proton and He-4 ion ranges with a reasonable accuracy.

Keywords: comparison, FNTD and OSLD detectors response, light ion beams, Monte Carlo simulations

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5743 Application of the Standard Deviation in Regulating Design Variation of Urban Solutions Generated through Evolutionary Computation

Authors: Mohammed Makki, Milad Showkatbakhsh, Aiman Tabony

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Computational applications of natural evolutionary processes as problem-solving tools have been well established since the mid-20th century. However, their application within architecture and design has only gained ground in recent years, with an increasing number of academics and professionals in the field electing to utilize evolutionary computation to address problems comprised from multiple conflicting objectives with no clear optimal solution. Recent advances in computer science and its consequent constructive influence on the architectural discourse has led to the emergence of multiple algorithmic processes capable of simulating the evolutionary process in nature within an efficient timescale. Many of the developed processes of generating a population of candidate solutions to a design problem through an evolutionary based stochastic search process are often driven through the application of both environmental and architectural parameters. These methods allow for conflicting objectives to be simultaneously, independently, and objectively optimized. This is an essential approach in design problems with a final product that must address the demand of a multitude of individuals with various requirements. However, one of the main challenges encountered through the application of an evolutionary process as a design tool is the ability for the simulation to maintain variation amongst design solutions in the population while simultaneously increasing in fitness. This is most commonly known as the ‘golden rule’ of balancing exploration and exploitation over time; the difficulty of achieving this balance in the simulation is due to the tendency of either variation or optimization being favored as the simulation progresses. In such cases, the generated population of candidate solutions has either optimized very early in the simulation, or has continued to maintain high levels of variation to which an optimal set could not be discerned; thus, providing the user with a solution set that has not evolved efficiently to the objectives outlined in the problem at hand. As such, the experiments presented in this paper seek to achieve the ‘golden rule’ by incorporating a mathematical fitness criterion for the development of an urban tissue comprised from the superblock as its primary architectural element. The mathematical value investigated in the experiments is the standard deviation factor. Traditionally, the standard deviation factor has been used as an analytical value rather than a generative one, conventionally used to measure the distribution of variation within a population by calculating the degree by which the majority of the population deviates from the mean. A higher standard deviation value delineates a higher number of the population is clustered around the mean and thus limited variation within the population, while a lower standard deviation value is due to greater variation within the population and a lack of convergence towards an optimal solution. The results presented will aim to clarify the extent to which the utilization of the standard deviation factor as a fitness criterion can be advantageous to generating fitter individuals in a more efficient timeframe when compared to conventional simulations that only incorporate architectural and environmental parameters.

Keywords: architecture, computation, evolution, standard deviation, urban

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5742 Challenges of Water License in Agriculture Sector in British Columbia: An Exploratory Sociological Inquiry

Authors: Mandana Karimi, Martha McMahon

Abstract:

One of the most important consequences of water scarcity worldwide is the increase in conflicts over water issues, reduced access to clean water, food shortages, energy shortages, and reduced economic development. The extreme weather conditions in British Columbia are because of climate change, which is leading to water scarcity becoming a serious issue affecting British Columbians, aquatic ecosystems, the BC water policy, agriculture, and the economy. In light of climate change and water stress, the British Columbia government introduced a new water legislation in 2016 named the Water Sustainability Act to manage water resources in British Columbia. So, this study aimed to present a deep understanding emanating from the political and social dimensions of the new water policy in BC in the agriculture sector and which sociological paradigm governs the current water policy (WSA) in BC. Policy analysis based on the water problem representation approach was used to present the problem and solutions identified by the water policy in the agricultural sector in BC. The results of the policy analysis highlighted that the Water Sustainability Act is governed by a positivist and modernist approach because the groundwater license is the measurable situation to access the adequate quantity of water for the farmers. In addition, by the positivist paradigm water resources are conceptualized as a commodity to be bought and sold. Under the positivist approach, the measurable parameter of groundwater is also applied based on the top-down approach for water management to show the use of water resources for economic development. In addition, the findings of the policy analysis suggest that alternative paradigms, such as relational ontology, ecofeminism, and indigenous knowledge, could be applied in introducing water policies to shift from the positivist or modernist paradigm. These new paradigms present the potential for environmental policies like the Water Sustainability Act, based on partnership, and collaboration and with an explicit emphasis on protecting water for nature.

Keywords: water governance, Water Sustainability Act, water policy, small-scale farmer, policy analysis

Procedia PDF Downloads 58
5741 Advanced Stability Criterion for Time-Delayed Systems of Neutral Type and Its Application

Authors: M. J. Park, S. H. Lee, C. H. Lee, O. M. Kwon

Abstract:

This paper investigates stability problem for linear systems of neutral type with time-varying delay. By constructing various Lyapunov-Krasovskii functional, and utilizing some mathematical techniques, the sufficient stability conditions for the systems are established in terms of linear matrix inequalities (LMIs), which can be easily solved by various effective optimization algorithms. Finally, some illustrative examples are given to show the effectiveness of the proposed criterion.

Keywords: neutral systems, time-delay, stability, Lyapnov method, LMI

Procedia PDF Downloads 339
5740 Spatio-Temporal Analysis of Drought in Cholistan Region, Pakistan: An Application of Standardized Precipitation Index

Authors: Qurratulain Safdar

Abstract:

Drought is a temporary aberration in contrast to aridity, as it is a permanent feature of climate. Virtually, it takes place in all types of climatic regions that range from high to low rainfall areas. Due to the wide latitudinal extent of Pakistan, there is seasonal and annual variability in rainfall. The south-central part of the country is arid and hyper-arid. This study focuses on the spatio-temporal analysis of droughts in arid and hyperarid region of Cholistan using the standardized precipitation index (SPI) approach. This study has assessed the extent of recurrences of drought and its temporal vulnerability to drought in Cholistan region. Initially, the paper described the geographic setup of the study area along with a brief description of the drought conditions that prevail in Pakistan. The study also provides a scientific foundation for preparing literature and theoretical framework in-line with the selected parameters and indicators. Data were collected both from primary and secondary data sources. Rainfall and temperature data were obtained from Pakistan Meteorology Department. By applying geostatistical approach, a standardized precipitation index (SPI) was calculated for the study region, and the value of spatio-temporal variability of drought and its severity was explored. As a result, in-depth spatial analysis of drought conditions in Cholistan area was found. Parallel to this, drought-prone areas with seasonal variation were also identified using Kriging spatial interpolation techniques in a GIS environment. The study revealed that there is temporal variation in droughts' occurrences both in time series and SPI values. The paper is finally concluded, and strategic plan was suggested to minimize the impacts of drought.

Keywords: Cholistan desert, climate anomalies, metrological droughts, standardized precipitation index

Procedia PDF Downloads 195
5739 Increasing Creativity in Virtual Learning Space for Developing Creative Cities

Authors: Elham Fariborzi, Hoda Anvari Kazemabad

Abstract:

Today, ICT plays an important role in all matters and it affects the development of creative cities. According to virtual space in this technology, it use especially for expand terms like smart schools, Virtual University, web-based training and virtual classrooms that is in parallel with the traditional teaching. Nowadays, the educational systems in different countries such as Iran are changing and start increasing creativity in the learning environment. It will contribute to the development of innovative ideas and thinking of the people in this environment; such opportunities might be cause scientific discovery and development issues. The creativity means the ability to generate ideas and numerous, new and suitable solutions for solving the problems of real and virtual individuals and society, which can play a significant role in the development of creative current physical cities or virtual borders ones in the future. The purpose of this paper is to study strategies to increase creativity in a virtual learning to develop a creative city. In this paper, citation/ library study was used. The full description given in the text, including how to create and enhance learning creativity in a virtual classroom by reflecting on performance and progress; attention to self-directed learning guidelines, efficient use of social networks, systematic discussion groups and non-intuitive targeted controls them by involved factors and it may be effective in the teaching process regarding to creativity. Meanwhile, creating a virtual classroom the style of class recognizes formally the creativity. Also the use of a common model of creative thinking between student/teacher is effective to solve problems of virtual classroom. It is recommended to virtual education’ authorities in Iran to have a special review to the virtual curriculum for increasing creativity in educational content and such classes to be witnesses more creative in Iran's cities.

Keywords: virtual learning, creativity, e-learning, bioinformatics, biomedicine

Procedia PDF Downloads 352
5738 Using Artificial Neural Networks for Optical Imaging of Fluorescent Biomarkers

Authors: K. A. Laptinskiy, S. A. Burikov, A. M. Vervald, S. A. Dolenko, T. A. Dolenko

Abstract:

The article presents the results of the application of artificial neural networks to separate the fluorescent contribution of nanodiamonds used as biomarkers, adsorbents and carriers of drugs in biomedicine, from a fluorescent background of own biological fluorophores. The principal possibility of solving this problem is shown. Use of neural network architecture let to detect fluorescence of nanodiamonds against the background autofluorescence of egg white with high accuracy - better than 3 ug/ml.

Keywords: artificial neural networks, fluorescence, data aggregation, biomarkers

Procedia PDF Downloads 693
5737 The Culex Pipiens Niche: Assessment with Climatic and Physiographic Variables via a Geographic Information System

Authors: Maria C. Proença, Maria T. Rebelo, Marília Antunes, Maria J. Alves, Hugo Osório, Sofia Cunha, João Casaca

Abstract:

Using a geographic information system (GIS), the relations between a georeferenced data set of Culex pipiens sl. mosquitoes collected in Portugal mainland during seven years (2006-2012) and meteorological and physiographic parameters such as: air relative humidity, air temperature (minima, maxima and mean daily temperatures), daily total rainfall, altitude, land use/land cover and proximity to water bodies are evaluated. Focus is on the mosquito females; the characterization of its habitat is the key for the planning of chirurgical non-aggressive prophylactic countermeasures to avoid ambient degradation. The GIS allow for the spatial determination of the zones were the mosquito mean captures has been above average; using the meteorological values at these coordinates, the limits of each parameter are identified/computed. The meteorological parameters measured at the net of weather stations all over the country are averaged by month and interpolated to produce raster maps that can be segmented according to the thresholds obtained for each parameter. The intersection of the maps obtained for each month show the evolution of the area favorable to the species through the mosquito season, which is from May to October at these latitudes. In parallel, mean and above average captures were related to the physiographic parameters. Three levels of risk could be identified for each parameter, using above average captures as an index. The results were applied to the suitability meteorological maps of each month. The Culex pipiens critical niche is delimited, reflecting the critical areas and the level of risk for transmission of the pathogens to which they are competent vectors (West Nile virus, iridoviruses, rheoviruses and parvoviruses).

Keywords: Culex pipiens, ecological niche, risk assessment, risk management

Procedia PDF Downloads 526
5736 Motion Planning and Simulation Design of a Redundant Robot for Sheet Metal Bending Processes

Authors: Chih-Jer Lin, Jian-Hong Hou

Abstract:

Industry 4.0 is a vision of integrated industry implemented by artificial intelligent computing, software, and Internet technologies. The main goal of industry 4.0 is to deal with the difficulty owing to competitive pressures in the marketplace. For today’s manufacturing factories, the type of production is changed from mass production (high quantity production with low product variety) to medium quantity-high variety production. To offer flexibility, better quality control, and improved productivity, robot manipulators are used to combine material processing, material handling, and part positioning systems into an integrated manufacturing system. To implement the automated system for sheet metal bending operations, motion planning of a 7-degrees of freedom (DOF) robot is studied in this paper. A virtual reality (VR) environment of a bending cell, which consists of the robot and a bending machine, is established using the virtual robot experimentation platform (V-REP) simulator. For sheet metal bending operations, the robot only needs six DOFs for the pick-and-place or tracking tasks. Therefore, this 7 DOF robot has more DOFs than the required to execute a specified task; it can be called a redundant robot. Therefore, this robot has kinematic redundancies to deal with the task-priority problems. For redundant robots, Pseudo-inverse of the Jacobian is the most popular motion planning method, but the pseudo-inverse methods usually lead to a kind of chaotic motion with unpredictable arm configurations as the Jacobian matrix lose ranks. To overcome the above problem, we proposed a method to formulate the motion planning problems as optimization problem. Moreover, a genetic algorithm (GA) based method is proposed to deal with motion planning of the redundant robot. Simulation results validate the proposed method feasible for motion planning of the redundant robot in an automated sheet-metal bending operations.

Keywords: redundant robot, motion planning, genetic algorithm, obstacle avoidance

Procedia PDF Downloads 135
5735 Covalent Binding of Cysteine to a Sol-Gel Material for Cadmium Biosorption from Aqueous Solutions

Authors: Claudiu Marcu, Cristina Paul, Adelina Andelescu, Corneliu Mircea Davidescu, Francisc Péter

Abstract:

Heavy metal pollution has become a more serious environmental problem in the last several decades as a result of its toxicity and insusceptibility to the environment. Methods for removing metal ions from aqueous solution mainly consist of physical, chemical and biochemical procedures. Biosorption is defined as the removal of metal or metalloid species, compounds and particulates from solution by a biological material. Biosorption represents a very attractive method for the removal of toxic metal ions from aqueous effluents because it uses the ability of various biomass to bind the metal ions without the risk of releasing other toxic chemical compounds into the environment. The problem with using biomass or living cells as biosorbents is that their regeneration/reuse is often either impossible or very laborious. One of the most common chelating group found in biosorbents is the thiol group in cysteine. Therefore, we immobilized cysteine using covalent binding using glutaraldehyde as a linker on a synthetic sol-gel support obtained using 3-amino-propyl-trimetoxysilane and trimetoxysilane as precursors. The obtained adsorbents were used for removal of cadmium from aqueous solutions and the removal capacity was investigated in relation to the composition of the sol-gel hybrid composite, the loading of the biomolecule and the physical parameters of the biosorption process. In the same conditions, the bare sol-gel support without cysteine had no Cd removal effect, while the adsorbent with cysteine had an adsorption capacity up to 25.8 mg Cd/g adsorbent at pH 2.0 and 119 mg Cd/g adsorbent at pH 6.6, depending on cadmium concentration and adsorption conditions. We used atomic adsorption spectrometry to assess the cadmium concentration in the samples after the biosorbtion process. The parameters for the Freundlich and Langmuir adsorption isotherms where calculated from plotting the results of the adsorption experiments. The results for cysteine immobilization show a good loading capacity of the sol-gel support which indicates it could be used to immobilize metal binding proteins and by doing so boosting the heavy metal adsorption capacity of the biosorbent.

Keywords: biosorbtion, cadmium, cysteine covalent binding, sol-gel

Procedia PDF Downloads 287
5734 A Multi-Criteria Decision Method for the Recruitment of Academic Personnel Based on the Analytical Hierarchy Process and the Delphi Method in a Neutrosophic Environment

Authors: Antonios Paraskevas, Michael Madas

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For a university to maintain its international competitiveness in education, it is essential to recruit qualitative academic staff as it constitutes its most valuable asset. This selection demonstrates a significant role in achieving strategic objectives, particularly by emphasizing a firm commitment to the exceptional student experience and innovative teaching and learning practices of high quality. In this vein, the appropriate selection of academic staff establishes a very important factor of competitiveness, efficiency and reputation of an academic institute. Within this framework, our work demonstrates a comprehensive methodological concept that emphasizes the multi-criteria nature of the problem and how decision-makers could utilize our approach in order to proceed to the appropriate judgment. The conceptual framework introduced in this paper is built upon a hybrid neutrosophic method based on the Neutrosophic Analytical Hierarchy Process (N-AHP), which uses the theory of neutrosophy sets and is considered suitable in terms of a significant degree of ambiguity and indeterminacy observed in the decision-making process. To this end, our framework extends the N-AHP by incorporating the Neutrosophic Delphi Method (N-DM). By applying the N-DM, we can take into consideration the importance of each decision-maker and their preferences per evaluation criterion. To the best of our knowledge, the proposed model is the first which applies the Neutrosophic Delphi Method in the selection of academic staff. As a case study, it was decided to use our method for a real problem of academic personnel selection, having as the main goal to enhance the algorithm proposed in previous scholars’ work, and thus taking care of the inherent ineffectiveness which becomes apparent in traditional multi-criteria decision-making methods when dealing with situations alike. As a further result, we prove that our method demonstrates greater applicability and reliability when compared to other decision models.

Keywords: multi-criteria decision making methods, analytical hierarchy process, delphi method, personnel recruitment, neutrosophic set theory

Procedia PDF Downloads 103
5733 The Predictive Role of Attachment and Adjustment in the Decision-Making Process in Infertility

Authors: A. Luli, A. Santona

Abstract:

It is rare for individuals that are involved in a relationship to think about the possibility of having procreation problems in the near present or in the future. However, infertility is a condition that affects millions of people all around the world. Often, infertile individuals have to deal with experiences of psychological, relational and social problems. In these cases, they have to review their choices and take into consideration, if it is necessary, new ones. Different studies have examined the different decisions that infertile individuals have to go through dealing with infertility and its treatment, but none of them is focused on the decision-making style used by infertile individuals to solve their problem and on the factors that influences it. The aim of this paper is to define the style of decision-making used by infertile persons to give a solution to the ‘problem’ and the potential predictive role of the attachment and of the dyadic adjustment. The total sample is composed by 251 participants, divided in two groups: the experimental group composed by 114 participants, 62 males and 52 females, age between 25 and 59 years, and the control group composed by 137 participants, 65 males and 72 females, age between 22 and 49 years. The battery of instruments used is composed by: the General Decision Making Style (GDMS), the Experiences in Close Relationships Questionnaire Revised (ECR-R), Dyadic Adjustment Scale (DAS), and the Symptom Checklist-90-R (SCL-90-R). The results from the analysis of the samples showed a prevalence of the rational decision-making style for both males and females. No significant statistical difference was found between the experimental and control group. Also the analyses showed a significant statistical relationship between the decision making styles and the adult attachment styles for both males and females. In this case, only for males, there was a significant statistical difference between the experimental and the control group. Another significant statistical relationship was founded between the decision making styles and the adjustment scales for both males and females. Also in this case, the difference between the two groups was founded to be significant only of males. These results contribute to enrich the literature on the subject of decision-making styles in infertile individuals, showing also the predictive role of the attachment styles and the adjustment, confirming in this was the few results in the literature.

Keywords: adjustment, attachment, decision-making style, infertility

Procedia PDF Downloads 319
5732 Purpose-Driven Collaborative Strategic Learning

Authors: Mingyan Hong, Shuozhao Hou

Abstract:

Collaborative Strategic Learning (CSL) teaches students to use learning strategies while working cooperatively. Student strategies include the following steps: defining the learning task and purpose; conducting ongoing negotiation of the learning materials by deciding "click" (I get it and I can teach it – green card, I get it –yellow card) or "clunk" (I don't get it – red card) at the end of each learning unit; "getting the gist" of the most important parts of the learning materials; and "wrapping up" key ideas. Find out how to help students of mixed achievement levels apply learning strategies while learning content area in materials in small groups. The design of CSL is based on social-constructivism and Vygotsky’s best-known concept of the Zone of Proximal Development (ZPD). The definition of ZPD is the distance between the actual acquisition level as decided by individual problem solution case and the level of potential acquisition level, similar to Krashen (1980)’s i+1, as decided through the problem-solution case under the facilitator’s guidance, or in group work with other more capable members (Vygotsky, 1978). Vygotsky claimed that learners’ ideal learning environment is in the ZPD. An ideal teacher or more-knowledgable-other (MKO) should be able to recognize a learner’s ZPD and facilitates them to develop beyond it. Then the MKO is able to leave the support step by step until the learner can perform the task without aid. Steven Krashen (1980) proposed Input hypothesis including i+1 hypothesis. The input hypothesis models are the application of ZPD in second language acquisition and have been widely recognized until today. Krashen (2019)’s optimal language learning environment (2019) further developed the application of ZPD and added the component of strategic group learning. The strategic group learning is composed of desirable learning materials learners are motivated to learn and desirable group members who are more capable and are therefore able to offer meaningful input to the learners. Purpose-driven Collaborative Strategic Learning Model is a strategic integration of ZPD, i+1 hypothesis model, and Optimal Language Learning Environment Model. It is purpose driven to ensure group members are motivated. It is collaborative so that an optimal learning environment where meaningful input from meaningful conversation can be generated. It is strategic because facilitators in the model strategically assign each member a meaningful and collaborative role, e.g., team leader, technician, problem solver, appraiser, offer group learning instrument so that the learning process is structured, and integrate group learning and team building making sure holistic development of each participant. Using data collected from college year one and year two students’ English courses, this presentation will demonstrate how purpose-driven collaborative strategic learning model is implemented in the second/foreign language classroom, using the qualitative data from questionnaire and interview. Particular, this presentation will show how second/foreign language learners grow from functioning with facilitator or more capable peer’s aid to performing without aid. The implication of this research is that purpose-driven collaborative strategic learning model can be used not only in language learning, but also in any subject area.

Keywords: collaborative, strategic, optimal input, second language acquisition

Procedia PDF Downloads 119