Search results for: service cost and queue length cost
1327 Preventive Behaviors of Exposure to Secondhand Smoke among Women: A Study Based on the Health Belief Model
Authors: Arezoo Fallahi
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Introduction: Exposure to second-hand smoke is an important global health problem and threatens the health of people, especially children and women. The aim of this study was to determine the effect of education based on the Health Belief Model on preventive behaviors of exposure to secondhand smoke in women. Materials and Methods: This experimental study was performed in 2023in Sanandaj, west of Iran. Seventy-four people were selected by simple random sampling and divided into an intervention group (37 people) and a control group (37 people). Data collection tools included demographic characteristics and a second-hand smoke exposure questionnaire based on the Health Beliefs Model. The training in the intervention group was conducted in three one-hour sessions in the comprehensive health service centers in the form of lectures, pamphlets, and group discussions. Data were analyzed using SPSS software version 21 and statistical tests such as correlation, paired t-test, and independent t-test. Results: The intervention and control groups were homogeneous before education. They were similar in terms of mean scores of the Health Belief Model. However, after an educational intervention, some of the scores increased, including the mean perceived sensitivity score (from 17.62±2.86 to 19.75±1.23), perceived severity score (28.40±4.45 to 31.64±2), perceived benefits score (27.27±4.89 to 31.94±2.17), practice score (32.64±4.68 to 36.91±2.32) perceived barriers from 26.62±5.16 to 31.29±3.34, guide for external action (from 17.70±3.99 to 22/89 ±1.67), guide for internal action from (16.59±2.95 to 1.03±18.75), and self-efficacy (from 19.83 ±3.99 to 23.37±1.43) (P <0.05). Conclusion: The educational intervention designed based on the Health Belief Model in women was effective in performing preventive behaviors against exposure to secondhand smoke.Keywords: women, health behaviour, smoke, belive
Procedia PDF Downloads 521326 Requirements to Establish a Taxi Sharing System in an Urban Area
Authors: Morteza Ahmadpur, Ilgin Gokasar, Saman Ghaffarian
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That Transportation system plays an important role in management of societies is an undeniable fact and it is one of the most challenging issues in human beings routine life. But by increasing the population in urban areas, the demand for transportation modes also increase. Accordingly, it is obvious that more flexible and dynamic transportation system is required to satisfy peoples’ requirements. Nowadays, there is significant increase in number of environmental issues all over the world which is because of human activities. New technological achievements bring new horizons for humans and so they changed the life style of humans in every aspect of their life and transportation is not an exception. By using new technology, societies can modernize their transportation system and increase the feasibility of their system. Real–time Taxi sharing systems is one of the novel and most modern systems all over the world. For establishing this kind of system in an urban area it is required to use the most advanced technologies in a transportation system. GPS navigation devices, computers and social networks are just some parts of this kind of system. Like carpooling, real-time taxi sharing is one of the best ways to better utilize the empty seats in most cars and taxis, thus decreasing energy consumption and transport costs. It can serve areas not covered by a public transit system and act as a transit feeder service. Taxi sharing is also capable of serving one-time trips, not only recurrent commute trips or scheduled trips. In this study, we describe the requirements and parameters that we need to establish a useful real-time ride sharing system for an urban area. The parameters and requirements of this study can be used in any urban area.Keywords: transportation, intelligent transportation systems, ride-sharing, taxi sharing
Procedia PDF Downloads 4271325 Political Regimes, Political Stability and Debt Dependence in African Countries of Franc Zone: A Logistic Modeling
Authors: Nounamo Nguedie Yann Harold
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The factors behind the debt have been the subject of several studies in the literature. Pioneering studies based on the 'double deficit' approach linked indebtedness to the imbalance between savings and investment, the budget deficit and the current account deficit. Most studies on identifying factors that may stimulate or reduce the level of external public debt agree that the following variables are important explanatory variables in leveraging debt: the budget deficit, trade opening, current account and exchange rate, import, export, interest rate, term variation exchange rate, economic growth rate and debt service, capital flight, and over-indebtedness. Few studies addressed the impact of political factors on the level of external debt. In general, however, the IMF's stabilization programs in developing countries following the debt crisis have resulted in economic recession and the advent of political crises that have resulted in changes in governments. In this sense, political institutions are recognised as factors of accumulation of external debt in most developing countries. This paper assesses the role of political factors on the external debt level of African countries in the Franc Zone over the period 1985-2016. Data used come from World Bank and ICRG. Using a logit in panel, the results show that the more a country is politically stable, the lower the external debt compared to the gross domestic product. Political stability multiplies 1.18% the chances of being in the sustainable debt zone. For example, countries with good political institutions experience less severe external debt burdens than countries with bad political institutions.Keywords: African countries, external debt, Franc Zone, political factors
Procedia PDF Downloads 2191324 Factors Affecting the Adoption of Cloud Business Intelligence among Healthcare Sector: A Case Study of Saudi Arabia
Authors: Raed Alsufyani, Hissam Tawfik, Victor Chang, Muthu Ramachandran
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This study investigates the factors that influence the decision by players in the healthcare sector to embrace Cloud Business Intelligence Technology with a focus on healthcare organizations in Saudi Arabia. To bring this matter into perspective, this study primarily considers the Technology-Organization-Environment (TOE) framework and the Human Organization-Technology (HOT) fit model. A survey was hypothetically designed based on literature review and was carried out online. Quantitative data obtained was processed from descriptive and one-way frequency statistics to inferential and regression analysis. Data were analysed to establish factors that influence the decision to adopt Cloud Business intelligence technology in the healthcare sector. The implication of the identified factors was measured, and all assumptions were tested. 66.70% of participants in healthcare organization backed the intention to adopt cloud business intelligence system. 99.4% of these participants considered security concerns and privacy risk have been the most significant factors in the adoption of cloud Business Intelligence (CBI) system. Through regression analysis hypothesis testing point that usefulness, service quality, relative advantage, IT infrastructure preparedness, organization structure; vendor support, perceived technical competence, government support, and top management support positively and significantly influence the adoption of (CBI) system. The paper presents quantitative phase that is a part of an on-going project. The project will be based on the consequences learned from this study.Keywords: cloud computing, business intelligence, HOT-fit model, TOE, healthcare and innovation adoption
Procedia PDF Downloads 1681323 Study on the Prediction of Serviceability of Garments Based on the Seam Efficiency and Selection of the Right Seam to Ensure Better Serviceability of Garments
Authors: Md Azizul Islam
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Seam is the line of joining two separate fabric layers for functional or aesthetic purposes. Different kinds of seams are used for assembling the different areas or parts of the garment to increase serviceability. To empirically support the importance of seam efficiency on serviceability of garments, this study is focused on choosing the right type of seams for particular sewing parts of the garments based on the seam efficiency to ensure better serviceability. Seam efficiency is the ratio of seam strength and fabric strength. Single jersey knitted finished fabrics of four different GSMs (gram per square meter) were used to make the test garments T-shirt. Three distinct types of the seam: superimposed, lapped and flat seam was applied to the side seams of T-shirt and sewn by lockstitch (stitch class- 301) in a flat-bed plain sewing machine (maximum sewing speed: 5000 rpm) to make (3x4) 12 T-shirts. For experimental purposes, needle thread count (50/3 Ne), bobbin thread count (50/2 Ne) and the stitch density (stitch per inch: 8-9), Needle size (16 in singer system), stitch length (31 cm), and seam allowance (2.5cm) were kept same for all specimens. The grab test (ASTM D5034-08) was done in the Universal tensile tester to measure the seam strength and fabric strength. The produced T-shirts were given to 12 soccer players who wore the shirts for 20 soccer matches (each match of 90 minutes duration). Serviceability of the shirt were measured by visual inspection of a 5 points scale based on the seam conditions. The study found that T-shirts produced with lapped seam show better serviceability and T-shirts made of flat seams perform the lowest score in serviceability score. From the calculated seam efficiency (seam strength/ fabric strength), it was obvious that the performance (in terms of strength) of the lapped and bound seam is higher than that of the superimposed seam and the performance of superimposed seam is far better than that of the flat seam. So it can be predicted that to get a garment of high serviceability, lapped seams could be used instead of superimposed or other types of the seam. In addition, less stressed garments can be assembled by others seems like superimposed seams or flat seams.Keywords: seam, seam efficiency, serviceability, T-shirt
Procedia PDF Downloads 2001322 Ireland to US Food Tourism the Diaspora and the Locale
Authors: Catriona Hilliard
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Food identity is synonymous with many national tourism destinations and perceptions in tourist source markets – stereotypes could include snails in France; beer in Britain and Germany; paella in Spain - and is an accepted element of national identity that can be incorporated into tourism experiences. Irish transatlantic food connections are culturally strong with diaspora subsequent generations in the US displaying an online interest in traditional Irish food, even with a twist. Back ‘home’, the value of the local indigenous experience was a specific element of the way The Gathering 2013 was promoted to the Irish diaspora, developing community interest and input to tourism. Over the past 20 years, Ireland has realized the value of its food industry to tourism. This has included the establishment of food development programmes for the hospitality industry; food festivals as a possible element of the tourist experience; and a programmes of food ambassadors to market Irish produce and to encourage service providers to understand; utilize and incorporate this into their offerings. Irish produce is being now actively marketed as part of the proposed tourism experience, to particular segment markets including transatlantic visitors. In addition, individual providers are becoming aware of the value of the market, and how to gain from it. Also, networks of food providers have developed collaborative structures of promoting their experiences to audiences, displaying a cluster approach of tourism development towards that sector. A power point presentation will look at how Irish produce contributes to tourism marketing and promotion of Ireland to America; how that may have assisted sustainable development of communities here; and hopes to elicit some discussion relating to longer term identification of Irish food, as part of tourism, for the potential benefit of the ‘locale’.Keywords: Irish, USA, food, tourism
Procedia PDF Downloads 3881321 Rapid Proliferation of Tissue Culture Using of Olive (Olea Europea L.) cv.Zard
Authors: Majid Gharaipour Abbasabad
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This research is studying the effects that various densities of Zeatin, and BA hormones may have on the scale of transformation of plant nodes to new shoots, among seedlings produced by seed germination, and also surveys the amount of produced shoots and their lengths, inside the specific Olive seed lab medium (OM). It is also concerned with the effects that various densities of IBA hormone, and inoculating the shoots with Agrobacterium Rhizogenez A4 can have on shoots' root production. This is a totally random research, and each attendance group has had three occurrences, and ten samples per a hectare. The average amounts have been compared using Duncan's test method, which was done in 5% level. The results indicated that the highest rate of transformation of micro samples to shoots happened in the seed germination environments, containing Zetain with 5 mg, and also 15 mg per a liter densities. (respectively, 95% and 94%), while the highest rate of plants' stem production ,in micro samples, happened in the lab medium environments with 5mg per a liter Zetain density (4.5). In lab medium environments with 15 mg Zetain per liter, a decrease was observed in the number of produced stems (3.88). According to the produced stems' lenght, the longest stem length was observed in environments with 5 mg and also 15 mg per a liter Zetain, and 25 mg per a liter BA densities (respectively, 8.45 cm, 45.66 cm, 8.53 cm). Meanwhile, the lowest amount of transformation of micro samples to shoots, the lowest number of produced shoots, and the shortest shoots were observed in the environments without any hormones (respectively, 3.32 cm, 1.13, 19.66%). The results of root production in Olive indicated that attendance groups which were exposed to different hormones did not vary, and Agrobacterium Rhizogenez A4 had no effect on them, as well. The lowest root's growth rate (22%) happened in environments without any hormones and also, in environment with Agrobacterium Rhizogenez A4 (19.66%). The largest number of roots was observed in the environments, containing Agrobacterium Rhizogenez A4 plus IBA (10 mg/l) and Agrobacterium Rhizogenez A4 plus IBA (10 mg/l), (respectively, 8.46 and 8.70), which had a significant difference with environments merely containing 10 mg and 20 mg of IBA per a litre (respectively, 3.06 and 3.2). So it can be concluded that even though Agrobacterium Rhizogenez A4 had no impact on root's growth among shoots, it had an impact on the number of produced roots. It should be noted that even when the environment contained merely Agrobacterium Rhizogenez A4 without any hormones, only (1.16) roots were produced, which is significantly different from the attendance group with hormones (1.06).Keywords: olive-effect of hormones-germination of seed, densities of zeatin, BA hormones, agriculture
Procedia PDF Downloads 2901320 A Case Study of Alkali-Silica Reaction Induced Consistent Damage and Strength Degradation Evaluation in a Textile Mill Building Due to Slow-Reactive Aggregates
Authors: Ahsan R. Khokhar, Fizza Hassan
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Alkali-Silica Reaction (ASR) has been recognized as a potential cause of concrete degradation in the world since the 1940s. In Pakistan, mega hydropower structures like dams, weirs constructed from aggregates extracted from a local riverbed exhibited different levels of alkali-silica reactivity over an extended service period. The concrete expansion potential due to such aggregates has been categorized as slow-reactive. Apart from hydropower structures, ASR existence has been identified in the concrete structural elements of a Textile Mill building which used aggregates extracted from the nearby riverbed. The original structure of the Textile Mill was erected in the 80s with the addition of a textile ‘sizing and wrapping’ hall constructed in the 90s. In the years to follow, intensive spalling was observed in the structural members of the subject hall; enough to threat to the overall stability of the building. Limitations such as incomplete building data posed hurdles during the detailed structural investigation. The paper lists observations made while assessing the extent of damage and its effect on the building hall structure. Core testing and Petrographic tests were carried out as per the ASTM standards for strength degradation analysis followed by the identifying its root cause. Results confirmed significant structural strength reduction because of ASR which necessitated the formulation of an immediate re-strengthening solution. The paper also discusses the possible tracks of rehabilitative measures which are being adapted to stabilize the structure and seize further concrete expansion.Keywords: Alkali-Silica Reaction (ASR), concrete strength degradation, damage assessment, damage evaluation
Procedia PDF Downloads 1281319 Nurse Practitioner Led Pediatric Primary Care Clinic in a Tertiary Care Setting: Improving Access and Health Outcomes
Authors: Minna K. Miller, Chantel. E. Canessa, Suzanna V. McRae, Susan Shumay, Alissa Collingridge
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Primary care provides the first point of contact and access to health care services. For the pediatric population, the goal is to help healthy children stay healthy and to help those that are sick get better. Primary care facilitates regular well baby/child visits; health promotion and disease prevention; investigation, diagnosis and management of acute and chronic illnesses; health education; both consultation and collaboration with, and referral to other health care professionals. There is a protective association between regular well-child visit care and preventable hospitalization. Further, low adherence to well-child care and poor continuity of care are independently associated with increased risk of hospitalization. With a declining number of family physicians caring for children, and only a portion of pediatricians providing primary care services, it is becoming increasingly difficult for children and their families to access primary care. Nurse practitioners are in a unique position to improve access to primary care and improve health outcomes for children. Limited literature is available on the nurse practitioner role in primary care pediatrics. The purpose of this paper is to describe the development, implementation and evaluation of a Nurse Practitioner-led pediatric primary care clinic in a tertiary care setting. Utilizing the participatory, evidence-based, patient-focused process for advanced practice nursing (PEPPA framework), this paper highlights the results of the initial needs assessment/gap analysis, the new service delivery model, populations served, and outcome measures.Keywords: access, health outcomes, nurse practitioner, pediatric primary care, PEPPA framework
Procedia PDF Downloads 4931318 The Therapeutic Effects of Acupuncture on Oral Dryness and Antibody Modification in Sjogren Syndrome: A Meta-Analysis
Authors: Tzu-Hao Li, Yen-Ying Kung, Chang-Youh Tsai
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Oral dryness is a common chief complaint among patients with Sjőgren syndrome (SS), which is a disorder currently known as autoantibodies production; however, to author’s best knowledge, there has been no satisfying pharmacy to relieve the associated symptoms. Hence the effectiveness of other non-pharmacological interventions such as acupuncture should be accessed. We conducted a meta-analysis of randomized clinical trials (RCTs) which evaluated the effectiveness of xerostomia in SS. PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Chongqing Weipu Database (CQVIP), China Academic Journals Full-text Database, AiritiLibrary, Chinese Electronic Periodicals Service (CEPS), China National Knowledge Infrastructure (CNKI) Database were searches through May 12, 2018 to select studies. Data for evaluation of subjective and objective xerostomia was extracted and was assessed with random-effects meta-analysis. After searching, a total of 541 references were yielded and five RCTs were included, covering 340 patients dry mouth resulted from SS, among whom 169 patients received acupuncture and 171 patients were control group. Acupuncture group was associated with higher subjective response rate (odds ratio 3.036, 95% confidence interval [CI] 1.828 – 5.042, P < 0.001) and increased salivary flow rate (weighted mean difference [WMD] 3.066, 95% CI 2.969 – 3.164, P < 0.001), as an objective marker. In addition, two studies examined IgG levels, which were lower in the acupuncture group (WMD -166.857, 95% CI -233.138 - -100.576, P < 0.001). Therefore, in the present meta-analysis, acupuncture improves both subjective and objective markers of dry mouth with autoantibodies reduction in patients with SS and is considered as an option of non-pharmacological treatment for SS.Keywords: acupuncture, meta-analysis, Sjogren syndrome, xerostomia
Procedia PDF Downloads 1231317 Comparative Evaluation of a Dynamic Navigation System Versus a Three-Dimensional Microscope in Retrieving Separated Endodontic Files: An in Vitro Study
Authors: Mohammed H. Karim, Bestoon M. Faraj
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Introduction: instrument separation is a common challenge in the endodontic field. Various techniques and technologies have been developed to improve the retrieval success rate. This study aimed to compare the effectiveness of a Dynamic Navigation System (DNS) and a three-dimensional microscope in retrieving broken rotary NiTi files when using trepan burs and the extractor system. Materials and Methods: Thirty maxillary first bicuspids with sixty separate roots were split into two comparable groups based on a comprehensive Cone-Beam Computed Tomography (CBCT) analysis of the root length and curvature. After standardised access opening, glide paths, and patency attainment with the K file (sizes 10 and 15), the teeth were arranged on 3D models (three per quadrant, six per model). Subsequently, controlled-memory heat-treated NiTi rotary files (#25/0.04) were notched 4 mm from the tips and fractured at the apical third of the roots. The C-FR1 Endo file removal system was employed under both guidance to retrieve the fragments, and the success rate, canal aberration, treatment time and volumetric changes were measured. The statistical analysis was performed using IBM SPSS software at a significance level of 0.05. Results: The microscope-guided group had a higher success rate than the DNS guidance, but the difference was insignificant (p > 0.05). In addition, the microscope-guided drills resulted in a substantially lower proportion of canal aberration, required less time to retrieve the fragments and caused a minor change in the root canal volume (p < 0.05). Conclusion: Although dynamically guided trephining with the extractor can retrieve separated instruments, it is inferior to three-dimensional microscope guidance regarding treatment time, procedural errors, and volume change.Keywords: dynamic navigation system, separated instruments retrieval, trephine burs and extractor system, three-dimensional video microscope
Procedia PDF Downloads 971316 Superchaotropicity: Grafted Surface to Probe the Adsorption of Nano-Ions
Authors: Raimoana Frogier, Luc Girard, Pierre Bauduin, Diane Rebiscoul, Olivier Diat
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Nano-ions (NIs) are ionic species or clusters of nanometric size. Their low charge density and the delocalization of their charges give special properties to some of NIs belonging to chemical classes of polyoxometalates (POMs) or boron clusters. They have the particularity of interacting non-covalently with neutral hydrated surface or interfaces such as assemblies of surface-active molecules (micelles, vesicles, lyotropic liquid crystals), foam bubbles or emulsion droplets. This makes possible to classify those NIs in the Hofmeister series as superchaotropic ions. The mechanism of adsorption is complex, linked to the simultaneous dehydration of the ion and the molecule or supramolecular assembly with which it can interact, all with an enthalpic gain on the free energy of the system. This interaction process is reversible and is sufficiently pronounced to induce changes in molecular and supramolecular shape or conformation, phase transitions in the liquid phase, all at sub-millimolar ionic concentrations. This new property of some NIs opens up new possibilities for applications in fields as varied as biochemistry for solubilization, recovery of metals of interest by foams in the form of NIs... In order to better understand the physico-chemical mechanisms at the origin of this interaction, we use silicon wafers functionalized by non-ionic oligomers (polyethylene glycol chains or PEG) to study in situ by X-ray reflectivity this interaction of NIs with the grafted chains. This study carried out at ESRF (European Synchrotron Radiation Facility) and has shown that the adsorption of the NIs, such as POMs, has a very fast kinetics. Moreover the distribution of the NIs in the grafted PEG chain layer was quantify. These results are very encouraging and confirm what has been observed on soft interfaces such as micelles or foams. The possibility to play on the density, length and chemical nature of the grafted chains makes this system an ideal tool to provide kinetic and thermodynamic information to decipher the complex mechanisms at the origin of this adsorption.Keywords: adsorption, nano-ions, solid-liquid interface, superchaotropicity
Procedia PDF Downloads 631315 E-Pharmacy: An e-Commerce Approach for Buying Medicine Online in Saudi Arabia
Authors: Syed Asif Hassan, Tabrej Khan, Ibrahim Manssor Al Najar, Mohammed Nasser
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The incredible accomplishment achieved by e-commerce in consumer durable area encouraged us to implement the online e-commerce model to tap the business benefits of electronic pharmacy in Saudi Arabia. The Kingdom of Saudi Arabia is famous for traditional herbal medicine. The rich heritage of traditional medicine has helped the mushrooming of regional pharmaceutical industries manufacturing drugs and other therapeutic against various diseases. However, the implementation of e-commerce in pharmacy has not been employed in the Kingdom of Saudi Arabia. The electronic pharmacy (E-Pharm) is an important sector that is flourishing across the globe and providing benefits of E-Pharm to the customers and suppliers all around the world. In this context, our web-based application of electronic pharmacy is the one of its kind in the Kingdom of Saudi Arabia. Surveys and personal interviews were used to identify key objectives of the proposed web-based portal. As per the findings of the surveys and personal interviews, following key objectives were identified: (a) The online platform will be used for ordering of prescription based medications for consumers. (b) The e-portal will provide space for pharmaceutical retailers who do not have an electronic platform to upload and sell their therapeutic products in an organized way. (c) The web portal will provide a tracking system to track the customer’s behavior like choice, offer, order, shipment, payment, etc. The web-based e-pharmacy portal will be developed using MySQL and PHP. The development of e-pharmacy web portal and e-prescription practices will not only improve the growth of electronic pharmacy but would also decrease the possibility of prescription alteration thus providing safety and improving the quality of service provided to the patient or consumers.Keywords: e-commerce, E-Pharm, MySQL, PHP
Procedia PDF Downloads 3961314 Effects of Drought Stress on Red Bean (Phaseolus vulgaris L.) Cultivars during Post-Flowering Growth Stage
Authors: Fariborz Shekari, Abdollah Javanmard, Amin Abbasi
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A pot experiment conducted to evaluate the response of two red bean cultivars, Sayad and Derakhshan, to water deficit stress during post-flowering growth stage and recovery potential of plants after stress. Treatments were included regular irrigation or control, water deficit during flowering stage, water deficit during pod formation and water deficit during pod filling period. Results showed that plant height had positive effects on yield of cultivars so that, the tall cultivar, ‘Sayad’, had higher yields. Stress application during flowering stage showed the highest negative impact on plant height and subsequently yield. The longest and the higher number of pods as well as the greatest number of seeds in pods were recorded in control treatment in ‘Sayad’. Stress application during pod formation resulted in the minimum amount of all studied traits in both cultivars. Stress encountered during seed filling period had the least effect on number and length of pods and seed/pod. However, 100 seeds weight significantly decreased. The highest amount for 100 seeds weight was record in control plants in ‘Derakhshan’. Under all treatments, ‘Sayad’ had higher biologic and seed yield compared to ‘Derakhshan’. The least amount of yield was recorded during stress application in pod formation and flowering period for ‘Sayad’ and ‘Derakhshan’ respectively. Harvest index of ‘Sayad’ was more affect by stress application. Data related to photosynthetic rate showed that during stress application, ‘Derakhshan’ owned rapid decline in photosynthesis. Beyond stress alleviation and onset of irrigation, recovery potential of ‘Sayad’ was higher than ‘Derakhshan’ and this cultivar was able to rapidly restore the photosynthesis rate of stress faced plants near control ones. In total, stress had lower impacts on photosynthetic rate of ‘Sayad’ cultivar.Keywords: common bean, water stress, yield, yield components, photosynthetic rate
Procedia PDF Downloads 2991313 Omalizumab Therapy Experience for Asthma, at Zayed Military Hospital (ZMH) in United Arab Emirates
Authors: Shanza Akram, Samir Salah, Imran Saleem, Ashraf Alzaabi, Jassim Abdou
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Introduction: 300 million people worldwide are affected by asthma .In UAE, prevalence is around 10% (900,000 people).Patients with persistent symptoms despite using high dose ICS plus a second controller +/- OCS are considered to have severe asthma. Omalizumab (Xolaire) an IgE monoclonal antibody is approved as add on therapy for severe allergic asthma. Objective: To determine the efficacy of omalizumab based on clinical outcomes in our cohort of patient pre and post 52 weeks of treatment to assess safety and tolerability of treatment. Methods: Medical records of patients receiving omalizumab therapy for asthma at ZMH ,Abu Dhabi were retrospectively analyzed.Patients fulfilling the criteria of severe allergic asthma as per GINA guidelines were included. Asthma control over 12 months prior to and 12 months after commencement of omalizumab therapy was analysed by taking into account the number of exacerbations and hospitalizations in addition to maintenance of medication dosages, need for rescue reliever therapy and pulmonary function testing. Results: Total cohort of 21 patient (5 females), average age 41 years and av length of therapy 22 months were included. Seven patients (total 11/52%) managed to stop steroids on treatment while four were able to decrease the dosage. Mean exacerbation rate decreased from five/ year pre treatment to 1.36 while on treatment. Number of hospitalizations decreased from mean of two per year to 0.9 per year. Rescue reliever inhaler usage decreased from mean of 40 puffs to 15 puffs per week. 2 patients discontinued therapy, 1 due to lack of benefit (2 doses) and 2nd due to severe persistent side effects including local irritation, severe limb and joint pains after 6 months. Conclusion: Treatment with omalizumab showed effect in terms of reduced number of exacerbations, maintenance therapy and reliever medications. However, no improvement was seen in PFTs.There is room for improved documentation in terms of symptom recording and use of rescue medicationas as well as for better patient education and counselling in order to improve compliance.Keywords: asthma, omalizumab, severe allergic asthma, UAE
Procedia PDF Downloads 2911312 Tracing Digital Traces of Phatic Communion in #Mooc
Authors: Judith Enriquez-Gibson
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This paper meddles with the notion of phatic communion introduced 90 years ago by Malinowski, who was a Polish-born British anthropologist. It explores the phatic in Twitter within the contents of tweets related to moocs (massive online open courses) as a topic or trend. It is not about moocs though. It is about practices that could easily be hidden or neglected if we let big or massive topics take the lead or if we simply follow the computational or secret codes behind Twitter itself and third party software analytics. It draws from media and cultural studies. Though at first it appears data-driven as I submitted data collection and analytics into the hands of a third party software, Twitonomy, the aim is to follow how phatic communion might be practised in a social media site, such as Twitter. Lurking becomes its research method to analyse mooc-related tweets. A total of 3,000 tweets were collected on 11 October 2013 (UK timezone). The emphasis of lurking is to engage with Twitter as a system of connectivity. One interesting finding is that a click is in fact a phatic practice. A click breaks the silence. A click in one of the mooc website is actually a tweet. A tweet was posted on behalf of a user who simply chose to click without formulating the text and perhaps without knowing that it contains #mooc. Surely, this mechanism is not about reciprocity. To break the silence, users did not use words. They just clicked the ‘tweet button’ on a mooc website. A click performs and maintains connectivity – and Twitter as the medium in attendance in our everyday, available when needed to be of service. In conclusion, the phatic culture of breaking silence in Twitter does not have to submit to the power of code and analytics. It is a matter of human code.Keywords: click, Twitter, phatic communion, social media data, mooc
Procedia PDF Downloads 4101311 Radiation Annealing of Radiation Embrittlement of the Reactor Pressure Vessel
Authors: E. A. Krasikov
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Influence of neutron irradiation on RPV steel degradation are examined with reference to the possible reasons of the substantial experimental data scatter and furthermore – nonstandard (non-monotonous) and oscillatory embrittlement behavior. In our glance, this phenomenon may be explained by presence of the wavelike component in the embrittlement kinetics. We suppose that the main factor affecting steel anomalous embrittlement is fast neutron intensity (dose rate or flux), flux effect manifestation depends on state-of-the-art fluence level. At low fluencies, radiation degradation has to exceed normative value, then approaches to normative meaning and finally became sub normative. Data on radiation damage change including through the ex-service RPVs taking into account chemical factor, fast neutron fluence and neutron flux were obtained and analyzed. In our opinion, controversy in the estimation on neutron flux on radiation degradation impact may be explained by presence of the wavelike component in the embrittlement kinetics. Therefore, flux effect manifestation depends on fluence level. At low fluencies, radiation degradation has to exceed normative value, then approaches to normative meaning and finally became sub normative. Moreover as a hypothesis we suppose that at some stages of irradiation damaged metal have to be partially restored by irradiation i.e. neutron bombardment. Nascent during irradiation structure undergo occurring once or periodically transformation in a direction both degradation and recovery of the initial properties. According to our hypothesis, at some stage(s) of metal structure degradation neutron bombardment became recovering factor. As a result, oscillation arises that in turn leads to enhanced data scatter.Keywords: annealing, embrittlement, radiation, RPV steel
Procedia PDF Downloads 3391310 Hybrid Velocity Control Approach for Tethered Aerial Vehicle
Authors: Lovesh Goyal, Pushkar Dave, Prajyot Jadhav, GonnaYaswanth, Sakshi Giri, Sahil Dharme, Rushika Joshi, Rishabh Verma, Shital Chiddarwar
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With the rising need for human-robot interaction, researchers have proposed and tested multiple models with varying degrees of success. A few of these models performed on aerial platforms are commonly known as Tethered Aerial Systems. These aerial vehicles may be powered continuously by a tether cable, which addresses the predicament of the short battery life of quadcopters. This system finds applications to minimize humanitarian efforts for industrial, medical, agricultural, and service uses. However, a significant challenge in employing such systems is that it necessities attaining smooth and secure robot-human interaction while ensuring that the forces from the tether remain within the standard comfortable range for the humans. To tackle this problem, a hybrid control method that could switch between two control techniques: constant control input and the steady-state solution, is implemented. The constant control approach is implemented when a person is far from the target location, and error is thought to be eventually constant. The controller switches to the steady-state approach when the person reaches within a specific range of the goal position. Both strategies take into account human velocity feedback. This hybrid technique enhances the outcomes by assisting the person to reach the desired location while decreasing the human's unwanted disturbance throughout the process, thereby keeping the interaction between the robot and the subject smooth.Keywords: unmanned aerial vehicle, tethered system, physical human-robot interaction, hybrid control
Procedia PDF Downloads 951309 MicroRNA in Bovine Corpus Luteum during Early Pregnancy
Authors: Rreze Gecaj, Corina Schanzenbach, Benedikt Kirchner, Michael Pfaffl, Bajram Berisha
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The maintenance of corpus lutem (CL) during early pregnancy in cattle is a critical and multifarious process. A luteotrophic mechanism originating from the embryo is widely accepted as the triggering signal for the CL maintenance. In the cattle, it is the interferon-tau (IFNT) secretion form conceptus that prevents CL regression and ensures progesterone production for the establishment of pregnancy. In addition to endocrine and paracrine signals, microRNA (miRNA) can also support CL sustainability during early pregnancy. MiRNA are small non-coding nucleic acids that regulate gene expression post-transcriptionally and are shown to be involved in the modulation of CL function. However, the examination of miRNAs in corpus luteum function at the early pregnancy still remains largely uncovered. This study aims at profiling the expression of miRNA in CL during the early pregnancy in cattle by comparing it with the CL form late cycle and with the regressed CL. Corpora lutea were assigned in two different groups during the cycle (C13 group, late CL: days 13-18 and C18, regressed CL group: day >18) and during the early pregnancy (group P: 1-2 month). The estrous cycle was determined by macroscopic examination and to age the fetus crown-rump length measurement was applied. A total of 9 corpora lutea from individual animals were included in the study, three corpora lutea for each group. MiRNAs population was profiled using small RNA next-generation sequencing and biologically significant miRNAs were evaluated for their differential expression using the DESeq2-methodology. We show that 6 differentially expressed miRNAs (bta-mir-2890, -2332, -2441-3p, -148b, -1248 and -29c) are common to both comparisons, P vs C13 and P vs C18. While for each stage individually we have identified unique miRNAs differentially expressed only for the given comparison. bta-miR-23a and -769 were unique miRNAs differentially expressed in P vs C13, whereas forty-four unique miRNAs were identified as differentially expressed in P vs C18. These data confirm that miRNAs are highly abundant in luteal tissue during early pregnancy and potentially regulate the CL maintenance at this stage of fetus development.Keywords: bovine, corpus luteum, microRNA, pregnancy, RNA-Seq
Procedia PDF Downloads 2571308 Assessment of the Thermal and Mechanical Properties of Bio-based Composite Materials for Thermal Insulation
Authors: Nega Tesfie Asfaw, Rafik Absi, Labouda B. A, Ikram El Abbassi
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Composite materials have come to the fore a few decades ago because of their superior insulation performances. Recycling natural fiber composites and natural fiber reinforcement of waste materials are other steps for conserving resources and the environment. This paper reviewed the Thermal properties (Thermal conductivity, Effusivity, and Diffusivity) and Mechanical properties (Compressive strength, Flexural strength, and Tensile strength) of bio-composite materials for thermal insulation in the construction industry. For several years, the development of the building materials industry has placed a special emphasis on bio-source materials. According to recent studies, most natural fibers have good thermal insulating qualities and good mechanical properties. To determine the thermal and mechanical performance of bio-composite materials in construction most research used experimental methods. the results of the study show that these natural fibers have allowed us to optimize energy consumption in a building and state that density, porosity, percentage of fiber, the direction of heat flow orientation of the fiber, and the shape of the specimen are the main elements that limit the thermal performance and also showed that density, porosity, Type of Fiber, Fiber length, orientation and weight percentage loading, Fiber-matrix adhesion, Choice of the polymer matrix, Presence of void are the main elements that limit the mechanical performance of the insulation material. Based on the results of this reviewed paper Moss fibers (0.034W/ (m. K)), Wood Fiber (0.043 W/ (m. K)), Wheat straw (0.046 W/ (m. K), and corn husk fibers (0.046 W/ (m. K) are a most promising solution for energy efficiency for construction industry with interesting insulation properties and with good acceptable mechanical properties. Finally, depending on the best fibers used for insulation applications in the construction sector, the thermal performance rate of various fibers reviewed in this article are analyzed. Due to Typha's high porosity, the results indicated that Typha australis fiber had a better thermal performance rate of 89.03% with clay.Keywords: bio-based materials, thermal conductivity, compressive strength, thermal performance
Procedia PDF Downloads 261307 Analyzing the Support to Fisheries in the European Union: Modelling Budgetary Transfers in Wild Fisheries
Authors: Laura Angulo, Petra Salamon, Martin Banse, Frederic Storkamp
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Fisheries subsidies are focus on reduce management costs or deliver income benefits to fishers. In 2015, total fishery budgetary transfers in 31 OECD countries represented 35% of their total landing value. However, subsidies to fishing have adverse effects on trade and it has been claimed that they may contribute directly to overfishing. Therefore, this paper analyses to what extend fisheries subsidies may 1) influence capture production facing quotas and 2) affect price dynamics. The study uses the fish module in AGMEMOD (Agriculture Member States Modelling, details see Chantreuil et al. (2012)) which covers eight fish categories (cephalopods; crustaceans; demersal marine fish; pelagic marine fish; molluscs excl. cephalopods; other marine finfish species; freshwater and diadromous fish) for EU member states and other selected countries developed under the SUCCESS project. This model incorporates transfer payments directly linked to fisheries operational costs. As aquaculture and wild fishery are not included within the WTO Agreement on Agriculture, data on fisheries subsidies is obtained from the OECD Fisheries Support Estimates (FSE) database, which provides statistics on budgetary transfers to the fisheries sector. Since support has been moving from budgetary transfers to General Service Support Estimate the last years, subsidies in capture production may not present substantial effects. Nevertheless, they would still show the impact across countries and fish categories within the European Union.Keywords: AGMEMOD, budgetary transfers, EU Member States, fish model, fisheries support estimate
Procedia PDF Downloads 2441306 Legacy of Smart Cities on Urban Future: Discussing the Future of Smart City by Sharing Its Experiences
Authors: Arsalan Makinian
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Our future cities will constantly evolve the necessary technologies for tomorrow’s needs. Technologies which enable a better kind of prosperity and security. This paper reports on the precedent of a smart city from its beginning to prevalence among urbanism academic literature and reports of tech companies. The article aims to direct urban foresight studies and to build a pathway for the future of smart city concept by gathering theoretical and empirical experiences related to smart cities with both top-down and bottom-up approaches. It hopes to deliver results of different studies, pilot projects, and development strategies of some of the smart cities in order to allow a shareable knowledge to take shape and develop in terms of qualitative aspects of a smart city. Now the definition of the smart city goes beyond removing physical boundaries, changing the concept of mobility and providing electronic service for citizens, it now constitutes fields such as energy efficiency, economic competitiveness, protecting the environment and finally, it takes advantage of technology and data science to improve the quality of life. In the smart city, the role of citizens is considered as both final purpose and contributor. Emerging issues which are almost implications of advanced technologies -as the most important trends of the future- and their reflection on the society need to be foresighted. Educating and fostering knowledge of smartness is one of the targets of the smart city concept. In this regard, some of these smart cites have established research and development units to share their projects and smart city initiatives. Due to this fact, gaining experience and sharing the results of this subject is necessary for technology management and moving toward a smart urban future.Keywords: age of urban tech, bottom-up approach, role of citizens, smart city
Procedia PDF Downloads 1371305 Eco-Friendly Softener Extracted from Ricinus communis (Castor) Seeds for Organic Cotton Fabric
Authors: Fisaha Asmelash
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The processing of textiles to achieve a desired handle is a crucial aspect of finishing technology. Softeners can enhance the properties of textiles, such as softness, smoothness, elasticity, hydrophilicity, antistatic properties, and soil release properties, depending on the chemical nature used. However, human skin is sensitive to rough textiles, making softeners increasingly important. Although synthetic softeners are available, they are often expensive and can cause allergic reactions on human skin. This paper aims to extract a natural softener from Ricinus communis and produce an eco-friendly and user-friendly alternative due to its 100% herbal and organic nature. Crushed Ricinus communis seeds were soaked in a mechanical oil extractor for one hour with a 100g cotton fabric sample. The defatted cake or residue obtained after the extraction of oil from the seeds, also known as Ricinus communis meal, was obtained by filtering the raffinate and then dried at 1030c for four hours before being stored under laboratory conditions for the softening process. The softener was applied directly to 100% cotton fabric using the padding process, and the fabric was tested for stiffness, crease recovery, and drape ability. The effect of different concentrations of finishing agents on fabric stiffness, crease recovery, and drape ability was also analyzed. The results showed that the change in fabric softness depends on the concentration of the finish used. As the concentration of the finish was increased, there was a decrease in bending length and drape coefficient. Fabrics with a high concentration of softener showed a maximum decrease in drape coefficient and stiffness, comparable to commercial softeners such as silicon. The highest decrease in drape coefficient was found to be comparable with commercial softeners, silicon. Maximum increases in crease recovery were seen in fabrics treated with Ricinus communis softener at a concentration of 30gpl. From the results, the extracted softener proved to be effective in the treatment of 100% cotton fabricKeywords: ricinus communis, crease recovery, drapability, softeners, stiffness
Procedia PDF Downloads 911304 Status of Participative Governance Practices in Higher Education: Implications for Stakeholders' Transformative Role-Assumption
Authors: Endalew Fufa Kufi
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The research investigated the role of stakeholders such as students, teachers and administrators in the practices of good governance in higher education by looking into the special contributions of top-officials, teachers and students in ensuring workable ties and productive interchanges in Adama Science and Technology University. Attention was given to participation, fairness and exemplariness as key indicators of good governance. The target university was chosen for its familiarity for the researcher to get dependable data, access to respondent and management of the processing of data. Descriptive survey design was used for the purpose of describing concerned roles the stakeholders in the university governance in order to reflect on the nature of participation of the practices. Centres of the research were administration where supportive groups such as central administrators and underlying service-givers had parts and academia where teachers and students were target. Generally, 60 teachers, 40 students and 15 administrative officers were referents. Data were collected in the form of self-report through open-ended questionnaires. The findings indicated that, while vertical interchanges in terms of academic and administrative routines were had normal flow on top-down basis, planned practices of stakeholders in decision-making and reasonably communicating roles and changes in decisions with top-officials were not efficiently practiced. Moreover, the practices of good modelling were not witnessed to have existed to the fullest extent. Rather, existence of a very wide gap between the academic and administrative staffs was witnessed as was reflected the case between teachers and students. The implication was such that for shortage in participative atmosphere and weaning of fairness in governance, routine practices have been there as the vicious circles of governance.Keywords: governance, participative, stakeholders, transformative, role-assumption
Procedia PDF Downloads 3951303 Out of Hospital Cardiac Arrest in Kuala Lumpur: A Mixed Method Study on Incidence, Adherence to Protocol, and Issues
Authors: Mohd Said Nurumal, Sarah Sheikh Abdul Karim
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Information regarding out of hospital cardiac arrest incidence include outcome in Malaysia is limited and fragmented. This study aims to identify incidence and adherence to protocol of out of hospital cardiac arrest and also to explore the issues faced by the pre-hospital personnel in regards managing cardiac arrest victim in Kuala Lumpur, Malaysia. A mixed method approach combining the qualitative and quantitative study design was used. The 285 pre-hospital care data sheet of out of hospital cardiac arrest during the year of 2011 were examined by using checklists for identify the incidence and adherence to protocol. Nine semi-structured interviews and two focus group discussions were performed. For the incidence based on the overall out of hospital cardiac arrest cases that occurred in 2011 (n=285), the survival rates were 16.8%. For adherence to protocol, only 89 (41.8%) of the cases adhered to the given protocol and 124 did not adhere to such protocol. The qualitative information provided insight about the issues related to out of hospital cardiac arrest in every aspect. All the relevant qualitative data were merged into few categories relating issues that could affect the management of out of hospital cardiac arrest performed by pre-hospital care team. One of the essential elements in the out of hospital cardiac arrest handling by pre-hospital care is to ensure increase of survival rates and excellent outcomes by adhering to given protocols based on international standard benchmarks. Measures are needed to strengthen the quick activation of the pre-hospital care service, prompt bystander cardiopulmonary resuscitation, early defibrillation and timely advanced cardiac life support and also to tackle all the issues highlighted in qualitative results.Keywords: pre-hospital care, out of hospital cardiac arrest, incidence, protocol, mixed method research
Procedia PDF Downloads 4131302 Building Information Modelling Based Value for Money Assessment in Public-Private Partnership
Authors: Guoqian Ren, Haijiang Li, Jisong Zhang
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Over the past 40 years, urban development has undergone large-scale, high-speed expansion, beyond what was previously considered normal and in a manner not proportionally related to population growth or physical considerations. With more scientific and refined decision-making in the urban construction process, new urbanization approaches, aligned with public-private partnerships (PPPs) which evolved in the early 1990s, have become acceptable and, in some situations, even better solutions to outstanding urban municipal construction projects, especially in developing countries. However, as the main driving force to deal with urban public services, PPPs are still problematic regarding value for money (VFM) process in most large-scale construction projects. This paper therefore reviews recent PPP articles in popular project management journals and relevant toolkits, published in the last 10 years, to identify the indicators that influence VFM within PPPs across regions. With increasing concerns about profitability and environmental and social impacts, the current PPP structure requires a more integrated platform to manage multi-performance project life cycles. Building information modelling (BIM), a popular approach to the procurement process in AEC sectors, provides the potential to ensure VFM while also working in tandem with the semantic approach to holistically measure life cycle costs (LCC) and achieve better sustainability. This paper suggests that BIM applied to the entire PPP life cycle could support holistic decision-making regarding VFM processes and thus meet service targets.Keywords: public-private partnership, value for money, building information modelling, semantic approach
Procedia PDF Downloads 2091301 Prioritizing the Most Important Information from Contractors’ BIM Handover for Firefighters’ Responsibilities
Authors: Akram Mahdaviparsa, Tamera McCuen, Vahideh Karimimansoob
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Fire service is responsible for protecting life, assets, and natural resources from fire and other hazardous incidents. Search and rescue in unfamiliar buildings is a vital part of firefighters’ responsibilities. Providing firefighters with precise building information in an easy-to-understand format is a potential solution for mitigating the negative consequences of fire hazards. The negative effect of insufficient knowledge about a building’s indoor environment impedes firefighters’ capabilities and leads to lost property. A data rich building information modeling (BIM) is a potentially useful source in three-dimensional (3D) visualization and data/information storage for fire emergency response. Therefore, this research’s purpose is prioritizing the required information for firefighters from the most important information to the least important. A survey was carried out with firefighters working in the Norman Fire Department to obtain the importance of each building information item. The results show that “the location of exit doors, windows, corridors, elevators, and stairs”, “material of building elements”, and “building data” are the three most important information specified by firefighters. The results also implied that the 2D model of architectural, structural and way finding is more understandable in comparison with the 3D model, while the 3D model of MEP system could convey more information than the 2D model. Furthermore, color in visualization can help firefighters to understand the building information easier and quicker. Sufficient internal consistency of all responses was proven through developing the Pearson Correlation Matrix and obtaining Cronbach’s alpha of 0.916. Therefore, the results of this study are reliable and could be applied to the population.Keywords: BIM, building fire response, ranking, visualization
Procedia PDF Downloads 1321300 Analyzing the Shearing-Layer Concept Applied to Urban Green System
Authors: S. Pushkar, O. Verbitsky
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Currently, green rating systems are mainly utilized for correctly sizing mechanical and electrical systems, which have short lifetime expectancies. In these systems, passive solar and bio-climatic architecture, which have long lifetime expectancies, are neglected. Urban rating systems consider buildings and services in addition to neighborhoods and public transportation as integral parts of the built environment. The main goal of this study was to develop a more consistent point allocation system for urban building standards by using six different lifetime shearing layers: Site, Structure, Skin, Services, Space, and Stuff, each reflecting distinct environmental damages. This shearing-layer concept was applied to internationally well-known rating systems: Leadership in Energy and Environmental Design (LEED) for Neighborhood Development, BRE Environmental Assessment Method (BREEAM) for Communities, and Comprehensive Assessment System for Building Environmental Efficiency (CASBEE) for Urban Development. The results showed that LEED for Neighborhood Development and BREEAM for Communities focused on long-lifetime-expectancy building designs, whereas CASBEE for Urban Development gave equal importance to the Building and Service Layers. Moreover, although this rating system was applied using a building-scale assessment, “Urban Area + Buildings” focuses on a short-lifetime-expectancy system design, neglecting to improve the architectural design by considering bio-climatic and passive solar aspects.Keywords: green rating system, urban community, sustainable design, standardization, shearing-layer concept, passive solar architecture
Procedia PDF Downloads 5791299 Role of IT Systems in Corporate Recruitment: Challenges and Constraints
Authors: Brahim Bellali, Fatima Bellali
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The integration of information technology systems (ITS) into a company's human resources processes seems to be the appropriate solution to the problem of evolving and adapting its human resources management practices in order to be both more strategic and more efficient in terms of costs and service quality. In this context, the aim of this work is to study the impact of information technology systems (ITS) on the recruitment process. In this study, we targeted candidates who had recruited using IT tools. The target population consists of 34 candidates based in Casablanca, Morocco. In order to collect the data, a questionnaire had to be drawn up. The survey is based on a data sheet and a questionnaire that is divided into several sections to make it more structured and comprehensible. The results show that the majority of respondents say that companies are making greater use of online CV libraries and social networks as digital solutions during the recruitment process. The results also show that 50% of candidates say that the use of digital tools by companies would not slow them down when applying for a job and that these IT tools improve manual recruitment processes, while 44.1% think that they facilitate recruitment without any human intervention. The majority of respondents (52.9%) think that social networks are the digital solutions most often used by recruiters in the sourcing phase. The constraints of digital recruitment encountered are the dehumanization of human resources (44.1%) and the limited interaction during remote interviews (44.1%), which leaves no room for informal exchanges. Digital recruitment can be a highly effective strategy for finding qualified candidates in a variety of fields. Here are a few recommendations for optimizing your digital recruitment process: (1) Use online recruitment platforms: LinkedIn, Twitter, and Facebook ; (2) Use applicant tracking systems (ATS) ; (3) Develop a content marketing strategy.Keywords: IT systems, recruitment, challenges, constraints
Procedia PDF Downloads 321298 Morphology Evolution in Titanium Dioxide Nanotubes Arrays Prepared by Electrochemical Anodization
Authors: J. Tirano, H. Zea, C. Luhrs
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Photocatalysis has established as viable option in the development of processes for the treatment of pollutants and clean energy production. This option is based on the ability of semiconductors to generate an electron flow by means of the interaction with solar radiation. Owing to its electronic structure, TiO₂ is the most frequently used semiconductors in photocatalysis, although it has a high recombination of photogenerated charges and low solar energy absorption. An alternative to reduce these limitations is the use of nanostructured morphologies which can be produced during the synthesis of TiO₂ nanotubes (TNTs). Therefore, if possible to produce vertically oriented nanostructures it will be possible to generate a greater contact area with electrolyte and better charge transfer. At present, however, the development of these innovative structures still presents an important challenge for the development of competitive photoelectrochemical devices. This research focuses on established correlations between synthesis variables and 1D nanostructure morphology which has a direct effect on the photocatalytic performance. TNTs with controlled morphology were synthesized by two-step potentiostatic anodization of titanium foil. The anodization was carried out at room temperature in an electrolyte composed of ammonium fluoride, deionized water and ethylene glycol. Consequent thermal annealing of as-prepared TNTs was conducted in the air between 450 °C-550 °C. Morphology and crystalline phase of the TNTs were carried out by SEM, EDS and XRD analysis. As results, the synthesis conditions were established to produce nanostructures with specific morphological characteristics. Anatase was the predominant phase of TNTs after thermal treatment. Nanotubes with 10 μm in length, 40 nm in pore diameter and a surface-volume ratio of 50 are important in photoelectrochemical applications based on TiO₂ due to their 1D characteristics, high surface-volume ratio, reduced radial dimensions and high oxide/electrolyte interface. Finally, this knowledge can be used to improve the photocatalytic activity of TNTs by making additional surface modifications with dopants that improve their efficiency.Keywords: electrochemical anodization, morphology, self-organized nanotubes, TiO₂ nanotubes
Procedia PDF Downloads 156