Search results for: bio-sourced phase change material
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 16262

Search results for: bio-sourced phase change material

5822 Causes and Impacts of Marine Heatwaves in the Bay of Bengal Region in the Recent Period

Authors: Sudhanshu Kumar, Raghvendra Chandrakar, Arun Chakraborty

Abstract:

In the ocean, the temperature extremes have the potential to devastate marine habitats, ecosystems together with ensuing socioeconomic consequences. In recent years, these extreme events are more frequent and intense globally and their increasing trend is expected to continue in the upcoming decades. It recently attracted public interest, as well as scientific researchers, which motivates us to analyze the current marine heatwave (MHW) events in the Bay of Bengal region. we have isolated 107 MHW events (above 90th percentile threshold) in this region of the Indian Ocean and investigated the variation in duration, intensity, and frequency of MHW events during our test period (1982-2021). Our study reveals that in the study region the average of three MHW events per year with an increasing linear trend of 1.11 MHW events per decade. In the analysis, we found the longest MHW event which lasted about 99 days, which is far greater than an average MHW event duration. The maximum intensity was 5.29°C (above the climatology-mean), while the mean intensity was 2.03°C. In addition, we observed net heat flux accompanied by anticyclonic eddies to be the primary cause of these events. Moreover, we concluded that these events affect sea surface height and oceanic productivity, highlighting the adverse impact of MHWs on marine ecosystems.

Keywords: marine heatwaves, global warming, climate change, sea surface temperature, marine ecosystem

Procedia PDF Downloads 111
5821 Bridging Stress Modeling of Composite Materials Reinforced by Fiber Using Discrete Element Method

Authors: Chong Wang, Kellem M. Soares, Luis E. Kosteski

Abstract:

The problem of toughening in brittle materials reinforced by fibers is complex, involving all the mechanical properties of fibers, matrix, the fiber/matrix interface, as well as the geometry of the fiber. An appropriate method applicable to the simulation and analysis of toughening is essential. In this work, we performed simulations and analysis of toughening in brittle matrix reinforced by randomly distributed fibers by means of the discrete elements method. At first, we put forward a mechanical model of the contribution of random fibers to the toughening of composite. Then with numerical programming, we investigated the stress, damage and bridging force in the composite material when a crack appeared in the brittle matrix. From the results obtained, we conclude that: (i) fibers with high strength and low elasticity modulus benefit toughening; (ii) fibers with relatively high elastic modulus compared to the matrix may result in considerable matrix damage (spalling effect); (iii) employment of high-strength synthetic fiber is a good option. The present work makes it possible to optimize the parameters in order to produce advanced ceramic with desired performance. We believe combination of the discrete element method (DEM) with the finite element method (FEM) can increase the versatility and efficiency of the software developed.

Keywords: bridging stress, discrete element method, fiber reinforced composites, toughening

Procedia PDF Downloads 431
5820 Concept for Determining the Focus of Technology Monitoring Activities

Authors: Guenther Schuh, Christina Koenig, Nico Schoen, Markus Wellensiek

Abstract:

Identification and selection of appropriate product and manufacturing technologies are key factors for competitiveness and market success of technology-based companies. Therefore many companies perform technology intelligence (TI) activities to ensure the identification of evolving technologies at the right time. Technology monitoring is one of the three base activities of TI, besides scanning and scouting. As the technological progress is accelerating, more and more technologies are being developed. Against the background of limited resources it is therefore necessary to focus TI activities. In this paper, we propose a concept for defining appropriate search fields for technology monitoring. This limitation of search space leads to more concentrated monitoring activities. The concept will be introduced and demonstrated through an anonymized case study conducted within an industry project at the Fraunhofer Institute for Production Technology. The described concept provides a customized monitoring approach, which is suitable for use in technology-oriented companies especially those that have not yet defined an explicit technology strategy. It is shown in this paper that the definition of search fields and search tasks are suitable methods to define topics of interest and thus to direct monitoring activities. Current as well as planned product, production and material technologies as well as existing skills, capabilities and resources form the basis of the described derivation of relevant search areas. To further improve the concept of technology monitoring the proposed concept should be extended during future research e.g. by the definition of relevant monitoring parameters.

Keywords: monitoring radar, search field, technology intelligence, technology monitoring

Procedia PDF Downloads 455
5819 Transient Enhanced LDO Voltage Regulator with Improved Feed Forward Path Compensation

Authors: A. Suresh, Sreehari Rao Patri, K. S. R. Krishnaprasad

Abstract:

An ultra low power capacitor less low-dropout voltage regulator with improved transient response using gain enhanced feed forward path compensation is presented in this paper. It is based on a cascade of a voltage amplifier and a transconductor stage in the feed forward path with regular error amplifier to form a composite gain-enhanced feed forward stage. It broadens the gain bandwidth and thus improves the transient response without substantial increase in power consumption. The proposed LDO, designed for a maximum output current of 100 mA in UMC 180 nm, requires a quiescent current of 69 µA. An undershoot of 153.79mV for a load current changes from 0mA to 100mA and an overshoot of 196.24mV for current change of 100mA to 0mA. The settling time is approximately 1.1 µs for the output voltage undershoot case. The load regulation is of 2.77 µV/mA at load current of 100mA. Reference voltage is generated by using an accurate band gap reference circuit of 0.8V.The costly features of SOC such as total chip area and power consumption is drastically reduced by the use of only a total compensation capacitance of 6pF while consuming power consumption of 0.096 mW.

Keywords: capacitor-less LDO, frequency compensation, transient response, latch, self-biased differential amplifier

Procedia PDF Downloads 437
5818 High Temperature Properties of Diffusion Brazed Joints of in 939 Ni-Base Superalloy

Authors: Hyunki Kang, Hi Won Jeong

Abstract:

The gas turbine operates for a long period of time under harsh, cyclic conditions of high temperature and pressure, where high turbine inlet temperature (TIT) can range from 1273 to 1873K. Therefore, Ni-base superalloys such as IN738, IN939, Rene 45, Rene 71, Rene 80, Mar M 247, CM 247, and CMSX-4 with excellent mechanical properties and resistance to creep, corrosion and oxidation at high temperatures are indeed used. Among the alloying additions for these alloys, aluminum (Al) and titanium (Ti) form gamma prime and enhance the high-temperature properties. However, when crack-damaged high-temperature turbine components such as blade and vane are repaired by fusion welding, they cause cracks. For example, when arc welding is applied to certain superalloys that contain Al and Ti with more than 3 wt.% and T3.5 wt%, respectively, such as IN738, IN939, Rene 80, Mar M 247, and CM 247, aging cracks occur. Therefore, repair technologies using diffusion brazing, which has less heat input into the base material, are being developed. Analysis of microstructural evolution of the brazed joints with a base metal of IN 939 Ni-base superalloy using brazing different filler metals was also carried out using X-ray diffraction, OEM, SEM-EDS, and EPMA. Stress rupture and high-temperature tensile strength properties were also measured to analyze the effects of different brazing heat cycles. The boron amount in the diffusion-affected zone (DAZ) was decreased towards the base metal and the formation of borides at grain boundaries was detected through EPMA.

Keywords: gas turbine, diffusion brazing, superalloy, gas turbine repair

Procedia PDF Downloads 32
5817 Overcoming the Obstacles to Green Campus Implementation in Indonesia

Authors: Mia Wimala, Emma Akmalah, Ira Irawati, M. Rangga Sururi

Abstract:

One way that has been aggressively implemented in creating a sustainable environment nowadays is through the implementation of green building concept. In order to ensure the success of its implementation, the support and initiation from educational institutions, especially higher education institutions are indispensable. This research was conducted to figure out the obstacles restraining the success of green campus implementation in Indonesia, as well as to propose strategies to overcome those obstacles. The data presented in this paper are mainly derived from interview and questionnaire distributed randomly to the staffs and students in 10 (ten) major institutions around Jakarta and West Java area. The data were further analyzed using ANOVA and SWOT analysis. According to 182 respondents, it is found that resistance to change, inadequate knowledge, information and understanding, no penalty for any environmental violation, lack of reward for green campus practices, lack of stringent regulations/laws, lack of management commitment, insufficient funds are the obstacles to the green campus movement in Indonesia. In addition, out of 6 criteria considered in UI GreenMetric World Ranking, education was the only criteria that had no significant difference between public and private universities in generating the green campus performance. The work concludes with recommendation of strategies to improve the implementation of green campus in the future.

Keywords: green campus, obstacles, sustainable, higher education institutions

Procedia PDF Downloads 209
5816 Investigating the Change in Self-Reliance Index in Drought Affected Pastoralist Communities of Borena Zone, Ethiopia

Authors: Soressa Tolcha Jarra

Abstract:

This research paper delves into the assessment of self-reliance indexes within drought-affected pastoralist communities of the Borena Zone, Ethiopia, in enhancing self-reliance among community members. Through a mixed-methods approach, including surveys, interviews, and field observations, the study evaluates the socioeconomic impact initiatives on livelihoods, resilience, and community empowerment. For measuring the progress of households towards self-reliance, the Self-Reliance-Index (SRI) was used by comparing the data/index score of a responding humanitarian-development-peace triple nexus project beneficiary from the baseline in October 2023 with data of the same responding beneficiary from this research done in May 2024. In this case, the 373 respondents that were interviewed during both surveys were chosen to represent the population of interest at the moment of each survey. The Self-Reliance-Index (SRI) has an average value of 2.02 for respondents during the baseline and an average value of 2.37 for respondents of the study, representing thus a positive difference of 0.35. Moreover, the study disaggregated the findings into four groups for further interpretation of the SRI analysis. The findings contribute to the discourse on sustainable development strategies in arid and semi-arid regions, offering practical recommendations for future interventions and policy formulation.

Keywords: Borena, drought, pastoralist, self-reliance index (SRI)

Procedia PDF Downloads 11
5815 Analyzing Preservice Teachers’ Attitudes toward Technology

Authors: Ahmet Oguz Akturk, Kemal Izci, Gurbuz Caliskan, Ismail Sahin

Abstract:

Rapid developments in technology are to necessitate societies to closely follow technological developments and change themselves to adopt those developments. It is obvious that one of the areas that are impacted from technological developments is education. Analyzing preservice teachers’ attitudes toward technology is crucial for both educational and professional purposes since teacher candidates are essential for educating future individual living in technological age. In this study, it is aimed to analyze preservice teachers’ attitudes toward technology and some variables (e.g., gender, daily internet usage and possessed technological devices) that predicting those attitudes. In this study, relational survey model used as research method and 329 preservice teachers who are studying in a large university located at the middle part of Turkey are voluntarily participated. Results of the study showed that mostly preservice teachers displayed positive attitudes toward technology while male preservice teachers’ attitudes toward technology was more positive than female preservice teachers. In order to analyze predicting factors for preservice teachers’ attitudes toward technology, stepwise multiple regressions were utilized. The results of stepwise multiple regression showed that daily internet use was the most strong predicting factor for predicting preservice teachers’ attitudes toward technology.

Keywords: attitudes toward technology, preservice teachers, gender, stepwise multiple regression analysis

Procedia PDF Downloads 277
5814 The Nutritive Value of Fermented Sago Pith (Metroxylon sago Rottb) Enriched with Micro Nutrients for Poultry Feed

Authors: Wizna, Helmi Muis, Hafil Abbas

Abstract:

An experiment was conducted to improve the nutrient value of sago pith (Metroxylon sago Rottb) supplemented with Zn, Sulfur and urea through fermentation by using cellulolytic bacteria (Bacillus amyloliquefaciens) as inoculums. The experiment was determination of the optimum dose combination (dosage of Zn, S and urea) for sago pith fermentation based on nutrient quality and quantity of these fermented products. The study was conducted in experimental method, using the completely randomized design in factorial with 3 treatments consist of: factor A (Dose of urea: A1 = 2.0%, A2 = 3.0%), factor B (Dose of S: B1 = 0.2%, B2 = 0.4%) and factor C (Dose of Zn: C1 = 0.0025%, C2 = 0.005%). Results of study showed that optimum condition for fermentation process of sago pith with B. amyloliquefaciens caused a change of nutrient content was obtained at urea (3%), S (0,2%), and Zn (0,0025%). This fermentation process was able to increase amino acid average, reduce crude fiber content by 67% and increase crude protein by 433%, which made the nutritional value of the product based on dry matter was 18.22% crude protein, 12.42% crude fiber, 2525 Kcal/kg metabolic energy and 65.73% nitrogen retention.

Keywords: fermentation, sago pith, sulfur, Zn, urea, Bacillus amyloliquefaciens

Procedia PDF Downloads 496
5813 Linking the Genetic Signature of Free-Living Soil Diazotrophs with Process Rates under Land Use Conversion in the Amazon Rainforest

Authors: Rachel Danielson, Brendan Bohannan, S.M. Tsai, Kyle Meyer, Jorge L.M. Rodrigues

Abstract:

The Amazon Rainforest is a global diversity hotspot and crucial carbon sink, but approximately 20% of its total extent has been deforested- primarily for the establishment of cattle pasture. Understanding the impact of this large-scale disturbance on soil microbial community composition and activity is crucial in understanding potentially consequential shifts in nutrient or greenhouse gas cycling, as well as adding to the body of knowledge concerning how these complex communities respond to human disturbance. In this study, surface soils (0-10cm) were collected from three forests and three 45-year-old pastures in Rondonia, Brazil (the Amazon state with the greatest rate of forest destruction) in order to determine the impact of forest conversion on microbial communities involved in nitrogen fixation. Soil chemical and physical parameters were paired with measurements of microbial activity and genetic profiles to determine how community composition and process rates relate to environmental conditions. Measuring both the natural abundance of 15N in total soil N, as well as incorporation of enriched 15N2 under incubation has revealed that conversion of primary forest to cattle pasture results in a significant increase in the rate of nitrogen fixation by free-living diazotrophs. Quantification of nifH gene copy numbers (an essential subunit encoding the nitrogenase enzyme) correspondingly reveals a significant increase of genes in pasture compared to forest soils. Additionally, genetic sequencing of both nifH genes and transcripts shows a significant increase in the diversity of the present and metabolically active diazotrophs within the soil community. Levels of both organic and inorganic nitrogen tend to be lower in pastures compared to forests, with ammonium rather than nitrate as the dominant inorganic form. However, no significant or consistent differences in total, extractable, permanganate-oxidizable, or loss-on-ignition carbon are present between the two land-use types. Forest conversion is associated with a 0.5- 1.0 unit pH increase, but concentrations of many biologically relevant nutrients such as phosphorus do not increase consistently. Increases in free-living diazotrophic community abundance and activity appear to be related to shifts in carbon to nitrogen pool ratios. Furthermore, there may be an important impact of transient, low molecular weight plant-root-derived organic carbon on free-living diazotroph communities not captured in this study. Preliminary analysis of nitrogenase gene variant composition using NovoSeq metagenomic sequencing indicates that conversion of forest to pasture may significantly enrich vanadium-based nitrogenases. This indication is complemented by a significant decrease in available soil molybdenum. Very little is known about the ecology of diazotrophs utilizing vanadium-based nitrogenases, so further analysis may reveal important environmental conditions favoring their abundance and diversity in soil systems. Taken together, the results of this study indicate a significant change in nitrogen cycling and diazotroph community composition with the conversion of the Amazon Rainforest. This may have important implications for the sustainability of cattle pastures once established since nitrogen is a crucial nutrient for forage grass productivity.

Keywords: free-living diazotrophs, land use change, metagenomic sequencing, nitrogen fixation

Procedia PDF Downloads 179
5812 Development of Colorimetric Based Microfluidic Platform for Quantification of Fluid Contaminants

Authors: Sangeeta Palekar, Mahima Rana, Jayu Kalambe

Abstract:

In this paper, a microfluidic-based platform for the quantification of contaminants in the water is proposed. The proposed system uses microfluidic channels with an embedded environment for contaminants detection in water. Microfluidics-based platforms present an evident stage of innovation for fluid analysis, with different applications advancing minimal efforts and simplicity of fabrication. Polydimethylsiloxane (PDMS)-based microfluidics channel is fabricated using a soft lithography technique. Vertical and horizontal connections for fluid dispensing with the microfluidic channel are explored. The principle of colorimetry, which incorporates the use of Griess reagent for the detection of nitrite, has been adopted. Nitrite has high water solubility and water retention, due to which it has a greater potential to stay in groundwater, endangering aquatic life along with human health, hence taken as a case study in this work. The developed platform also compares the detection methodology, containing photodetectors for measuring absorbance and image sensors for measuring color change for quantification of contaminants like nitrite in water. The utilization of image processing techniques offers the advantage of operational flexibility, as the same system can be used to identify other contaminants present in water by introducing minor software changes.

Keywords: colorimetric, fluid contaminants, nitrite detection, microfluidics

Procedia PDF Downloads 184
5811 Impact of Job Crafting on Work Engagement and Well-Being among Indian Working Professionals

Authors: Arjita Jhingran

Abstract:

The pandemic was a turning point for flexible employment. In today’s market, employees prefer companies that provide the autonomy to change their work environment and are flexible. Post pandemic employees have become accustomed to modifying, re-designing, and re-aligning their work environment, task, and the way they interact with co-workers based on their preferences after working from home for a long time. In this scenario, the concept of job crafting has come to the forefront, and research on the subject has expanded, particularly during COVID-19. Managers who provide opportunities to craft the job are driving enhanced engagement and well-being. The current study will aim to examine the impact of job crafting on work engagement and psychological well-being among 385 working professionals, ranging in the age group of 21- 39 years. (M age=30 years). The study will also draw comparisons between freelancers and full-time employees, as freelancers have been considered to have more autonomy over their job. A comparison-based among MNC or startups will be studied; as for the majority of startups, autonomy is a primary motivator. Moreover, a difference based on the level of experience will also be observed, which will add to the body of knowledge. The data will be collected through Job Crafting Questionnaire, Utrecht Work Engagement Scale, and Psychological Well-Being Scale. To infer the findings, correlation analysis will be used to study the relationship among variables, and a Three way ANOVA will be used to draw comparisons.

Keywords: job crafting, work engagement, well-being, freelancers, start-ups

Procedia PDF Downloads 96
5810 Voices and Pictures from an Online Course and a Face to Face Course

Authors: Eti Gilad, Shosh Millet

Abstract:

In light of the technological development and its introduction into the field of education, an online course was designed in parallel to the 'conventional' course for teaching the ''Qualitative Research Methods''. This course aimed to characterize learning-teaching processes in a 'Qualitative Research Methods' course studied in two different frameworks. Moreover its objective was to explore the difference between the culture of a physical learning environment and that of online learning. The research monitored four learner groups, a total of 72 students, for two years, two groups from the two course frameworks each year. The courses were obligatory for M.Ed. students at an academic college of education and were given by one female-lecturer. The research was conducted in the qualitative method as a case study in order to attain insights about occurrences in the actual contexts and sites in which they transpire. The research tools were open-ended questionnaire and reflections in the form of vignettes (meaningful short pictures) to all students as well as an interview with the lecturer. The tools facilitated not only triangulation but also collecting data consisting of voices and pictures of teaching and learning. The most prominent findings are: differences between the two courses in the change features of the learning environment culture for the acquisition of contents and qualitative research tools. They were manifested by teaching methods, illustration aids, lecturer's profile and students' profile.

Keywords: face to face course, online course, qualitative research, vignettes

Procedia PDF Downloads 405
5809 Channel Dynamics along the Northern Bank of the Upper Brahmaputra River and Formation of a Larger Island with the Loss of the Majuli Island

Authors: Luna Moni Das

Abstract:

This paper is an attempt to study the channel dynamics in the area bounded by the foothills of the eastern Himalayas in the north, the Brahmaputra in the south and southeast and eastern side and the Subansiri River in the west. There are many streams in this region and only a few are perennial. There are two major anabranches of the Brahmaputra called Kharkutia Xuti and Charikoria. All of these makes it a very dynamic area. The analysis done in this paper is based on the remote sensing data and mapping of the channel planforms in GIS environment. The temporal trend of the change in channel planform has been produced. This study shows that, during the period from 1973 to 2013, the streams/rivers originating in the north have experienced a reduction in the total length. The other most important result is that even though the western edge of Majuli Island is eroding faster there is a formation of a larger island in between Charikoria and Brahmaputra, that comprises of Majuli island and parts of Dhakuakhana subdivision of Lakhimpur District along the south of Charikoria river. The field study shows that the Kharkutia Xuti, that divides Majuli from Dhakuakhana, do not experience any flow from the Brahmaputra for the major portion of the year and Charikoria has developed as a major anabranch of the Brahmaputra.

Keywords: channel dynamics, Brahmaputra river, Majuli Island, sinuosity

Procedia PDF Downloads 108
5808 Antioxidant Effects of Withania Somnifera (Ashwagandha) on Brain

Authors: Manju Lata Sharma

Abstract:

Damage to cells caused by free radicals is believed to play a central role in the ageing process and in disease progression. Withania somnifera is widely used in ayurvedic medicine, and it is one of the ingredients in many formulations to increase energy, improve overall health and longevity and prevent disease. Withania somnifera possesses antioxidative properties. The antioxdant activity of Withania somnifera consisting of an equimolar concentration of active principles of sitoindoside VII-X and withaferin A. The antioxidant effect of Withania somnifera extract was investigated on lipid peroxidation (LPO), superoxide dismutase (SOD) and catalase (CAT) activity in mice. Aim: To study the antioxidant activity of an extract of Withania somnifera leaf against a mice model of chronic stress. Healthy swiss albino mice (3-4 months old) selected from an inbred colony were divided in to 6 groups. Biochemical estimation revealed that stress induced a significant change in SOD, LPO, CAT AND GPX. These stress induced perturbations were attenuated Withania somnifera (50 and 100 mg/kg BW). Result: Withania somnifera tended to normalize the augmented SOD and LPO activities and enhanced the activities of CAT and GPX. The result indicates that treatment with an alcoholic extract of Withania somnifera produced a significant decrease in LPO ,and an increase in both SOD and CAT in brain mice. This indicates that Withania somnifera extract possesses free radical scavenging activity .

Keywords: Withania somnifera, antioxidant, lipid peroxidation, brain

Procedia PDF Downloads 352
5807 How Rational Decision-Making Mechanisms of Individuals Are Corrupted under the Presence of Others and the Reflection of This on Financial Crisis Management Situations

Authors: Gultekin Gurcay

Abstract:

It is known that the most crucial influence of the psychological, social and emotional factors that affect any human behavior is to corrupt the rational decision making mechanism of the individuals and cause them to display irrational behaviors. In this regard, the social context of human beings influences the rationality of our decisions, and people tend to display different behaviors when they were alone compared to when they were surrounded by others. At this point, the interaction and interdependence of the behavioral finance and economics with the area of social psychology comes, where intentions and the behaviors of the individuals are being analyzed in the actual or implied presence of others comes into prominence. Within the context of this study, the prevalent theories of behavioral finance, which are The Prospect Theory, The Utility Theory Given Uncertainty and the Five Axioms of Choice under Uncertainty, Veblen’s Hidden Utility Theory, and the concept of ‘Overreaction’ has been examined and demonstrated; and the meaning, existence and validity of these theories together with the social context has been assessed. Finally, in this study the behavior of the individuals in financial crisis situations where the majority of the society is being affected from the same negative conditions at the same time has been analyzed, by taking into account how individual behavior will change according to the presence of the others.

Keywords: conditional variance coefficient, financial crisis, garch model, stock market

Procedia PDF Downloads 230
5806 Continuous Blood Pressure Measurement from Pulse Transit Time Techniques

Authors: Chien-Lin Wang, Cha-Ling Ko, Tainsong Chen

Abstract:

Pulse Blood pressure (BP) is one of the vital signs, and is an index that helps determining the stability of life. In this respect, some spinal cord injury patients need to take the tilt table test. While doing the test, the posture changes abruptly, and may cause a patient’s BP to change abnormally. This may cause patients to feel discomfort, and even feel as though their life is threatened. Therefore, if a continuous non-invasive BP assessment system were built, it could help to alert health care professionals in the process of rehabilitation when the BP value is out of range. In our research, BP assessed by the pulse transit time technique was developed. In the system, we use a self-made photoplethysmograph (PPG) sensor and filter circuit to detect two PPG signals and to calculate the time difference. The BP can immediately be assessed by the trend line. According to the results of this study, the relationship between the systolic BP and PTT has a highly negative linear correlation (R2=0.8). Further, we used the trend line to assess the value of the BP and compared it to a commercial sphygmomanometer (Omron MX3); the error rate of the system was found to be in the range of ±10%, which is within the permissible error range of a commercial sphygmomanometer. The continue blood pressure measurement from pulse transit time technique may have potential to become a convenience method for clinical rehabilitation.

Keywords: continous blood pressure measurement, PPG, time transit time, transit velocity

Procedia PDF Downloads 339
5805 128-Multidetector CT for Assessment of Optimal Depth of Electrode Array Insertion in Cochlear Implant Operations

Authors: Amina Sultan, Mohamed Ghonim, Eman Oweida, Aya Abdelaziz

Abstract:

Objective: To assess the diagnostic reliability of multi-detector CT in pre and post-operative evaluation of cochlear implant candidates. Material and Methods: The study includes 40 patients (18 males and 22 females); mean age 5.6 years. They were classified into two groups: Group A (20 patients): cochlear implant device was Nucleus-22 and Group B (20 patients): the device was MED-EL. Cochlear length (CL) and cochlear height (CH) were measured pre-operatively by 128-multidetector CT. Electrode length (EL) and insertion depth angle (α) were measured post-operatively by MDCT. Results: For Group A mean CL was 9.1 mm ± 0.4 SD; mean CH was 4.1 ± 0.3 SD; mean EL was 18 ± 2.7 SD; mean α angle was 299.05 ± 37 SD. Significant statistical correlation (P < 0.05) was found between preoperative CL and post-operative EL (r²=0.6); as well as EL and α angle (r²=0.7). Group B's mean CL was 9.1 mm ± 0.3 SD; mean CH was 4.1 ± 0.4 SD; mean EL was 27 ± 2.1 SD; mean α angle was 287.6 ± 41.7 SD. Significant statistical correlation was found between CL and EL (r²= 0.6) and α angle (r²=0.5). Also, a strong correlation was found between EL and α angle (r²=0.8). Significant statistical difference was detected between the two devices as regards to the electrode length. Conclusion: Multidetector CT is a reliable tool for preoperative planning and post-operative evaluation of the outcomes of cochlear implant operations. Cochlear length is a valuable prognostic parameter for prediction of the depth of electrode array insertion which can influence criteria of device selection.

Keywords: angle of insertion (α angle), cochlear implant (CI), cochlear length (CL), Multidetector Computed Tomography (MDCT)

Procedia PDF Downloads 183
5804 Use of Alternative Water Sources Based on a Rainwater in the Multi-Dwelling Urban Building 2030

Authors: Monika Lipska

Abstract:

Drinking water is water with a very high quality, and as such represents only 2.5% of the total quantity of all water in the world. For many years we have observed continuous increase in its consumption as a result of many factors such as: Growing world population (7 billion in 2011r.), increase of human lives comfort and – above all – the economic growth. Due to the rocketing consumption and growing costs of production of water with such high-quality parameters, we experience accelerating interest in alternative sources of obtaining potable water. One of the ways of saving this valuable material is using rainwater in the Urban Building. With an exponentially growing demand, the acquisition of additional sources of water is necessary to maintain the proper balance of all ecosystems. The first part of the paper describes what rainwater is and what are its potential sources and means of use, while the main part of the article focuses on the description of the methods of obtaining water from rain on the example of new urban building in Poland. It describes the method and installations of rainwater in the new urban building (“MBJ2030”). The paper addresses also the issue of monitoring of the whole recycling systems as well as the particular quality indicators important because of identification of the potential risks to human health. The third part describes the legal arrangements concerning the recycling of rainwater existing in different European Union countries with particular reference to Poland on example the new urban building in Warsaw.

Keywords: rainwater, potable water, non-potable water, Poland

Procedia PDF Downloads 402
5803 Modeling of Hydraulic Networking of Water Supply Subsystem Case of Addis Ababa

Authors: Solomon Weldegebriel Gebrelibanos

Abstract:

Water is one of the most important substances in human life that can give a human liberality with its cost and availability. Water comes from rainfall and runoff and reaches the ground as runoff that is stored in a river, ponds, and big water bodies, including sea and ocean and the remaining water portion is infiltrated into the ground to store in the aquifer. Water can serve human beings in various ways, including irrigation, water supply, hydropower and soon. Water supply is the main pillar of the water service to the human being. Water supply distribution in Addis Ababa arises from Legedadi, Akakai, and Gefersa. The objective of the study is to measure the performance of the water supply distribution in Addis Ababa city. The water supply distribution model is developed by computer-aided design software. The model can analyze the operational change, loss of water, and performance of the network. The two design criteria that have been employed to analyze the network system are velocity and pressure. The result shows that the customers are using the water at high pressure with low demand. The water distribution system is older than the expected service life with more leakage. Hence the study recommended that fixing Pressure valves and new distribution facilities can resolve the performance of the water supply system

Keywords: distribution, model, pressure, velocity

Procedia PDF Downloads 110
5802 The Effect of Nutrition Education on Glycemic and Lipidemic Control in Iranian Patients with Type 2 Diabetes

Authors: Samira Rabiei, Faezeh Askari, Reza Rastmanesh

Abstract:

Objective: To evaluate the effects of nutrition education and adherence to a healthy diet on glycemic and lipidemic control in patients with T2DM. Material and Methods: A randomized controlled trial was conducted on 494 patients with T2DM, aged 14-87 years from both sexes who were selected by convenience sampling from referees to Aliebneabitaleb hospital in Ghom. The participants were divided into two 247 person groups by stratified randomization. Both groups received a diet adjusted based on ideal body weight, and the intervention group was additionally educated about healthy food choices regarding diabetes. Information on medications, psychological factors, diet and physical activity was obtained from questionnaires. Blood samples were collected to measure FBS, 2 hPG, HbA1c, cholesterol, and triglyceride. After 2 months, weight and biochemical parameters were measured again. Independent T-test, Mann-Whitney, Chi-square, and Wilcoxon were used as appropriate. Logistic regression was used to determine the odds ratio of abnormal glycemic and lipidemic control according to the intervention. Results: The mean weight, FBS, 2 hPG, cholesterol and triglyceride after intervention were significantly lower than before that (p < 0.05). Discussion: Nutrition education plus a weigh reducer diet is more effective on glycemic and lipidemic control than a weight reducer diet, alone.

Keywords: type 2 diabetes mellitus, nutrition education, glycemic control, lipid profile

Procedia PDF Downloads 189
5801 Potential Application of Modified Diglycolamide Resin for Rare Earth Element Extraction

Authors: Junnile Romero, Ilhwan Park, Vannie Joy Resabal, Carlito Tabelin, Richard Alorro, Leaniel Silva, Joshua Zoleta, Takunda Mandu, Kosei Aikawa, Mayumi Ito, Naoki Hiroyoshi

Abstract:

Rare earth elements (REE) play a vital role in technological advancement due to their unique physical and chemical properties essential for various renewable energy applications. However, this increasing demand represents a challenging task for sustainability that corresponds to various research interests relating to the development of various extraction techniques, particularly on the extractant being used. In this study, TK221 (a modified polymer resin containing diglycolamide, carbamoyl methyl phosphine oxide (CMPO), and diglycolamide (DGA-N)) has been investigated as a conjugate extractant. FTIR and SEM analysis results confirmed the presence of CMPO and DGA-N being coated onto the PS-DVB support of TK221. Moreover, the kinetic rate law and adsorption isotherm batch test was investigated to understand the corresponding adsorption mechanism. The results show that REEs’ (Nd, Y, Ce, and Er) obtained pseudo-second-order kinetics and Langmuir isotherm, suggesting that the adsorption mechanism undergoes a single monolayer adsorption site via a chemisorption process. The Qmax values of Nd, Ce, Er, Y, and Fe were 45.249 mg/g, 43.103 mg/g, 35.088 mg/g, 15.552 mg/g, and 12.315 mg/g, respectively. This research further suggests that TK221 polymer resin can be used as an alternative absorbent material for an effective REE extraction.

Keywords: rare earth element, diglycolamide, characterization, extraction resin

Procedia PDF Downloads 97
5800 On the Paradigm Shift of the Overall Urban Design in China

Authors: Gaoyuan Wang, Tian Chen, Junnan Liu

Abstract:

Facing a period of major change that’s rarely seen in a century, China formulates the 14th Five-Year Plan and places emphasis on promoting high-quality development. In this context, the overall urban design has become a crucial and systematic tool for high-quality urban development. However, there are bottlenecks in the nature definition, content scope and transmission mechanisms of the current overall urban design in China. The paper interprets the emerging demands of the 14th Five-Year Plan on urban design in terms of new value-quality priority, new dynamic-space performance, new target-region coordination and new path-refined governance. Based on the new trend and appeal, the multi-dimensional thinking integrated with the major tasks of urban design are proposed accordingly, which is the biomass thinking in ecological, production and living element, the strategic thinking in spatial structure, the systematic thinking in the cityscape, the low-carbon thinking in urban form, the governance thinking in public space, the user thinking in design implementation. The paper explores the possibility of transforming the value thinking and technical system of urban design in China and provides a breakthrough path for the urban planning and design industry to better respond to the propositions of the country’s 14th Five-Year Plan.

Keywords: China’s 14th five-year plan, overall urban design, urban design thinking, transformation of urban design

Procedia PDF Downloads 248
5799 Tc-99m MIBI Scintigraphy to Differentiate Malignant from Benign Lesions, Detected on Planar Bone Scan

Authors: Aniqa Jabeen

Abstract:

The aim of this study was to evaluate the effectiveness of Tc-99m MIBI (Technetium 99-methoxy-iso-butyl-isonitrile) scintigraphy to differentiate malignancies from benign lesions, which were detected on planar bone scans. Materials and Methods: 59 patients with bone lesions were enrolled in the study. The scintigraphic findings were compared with the clinical, radiological and the histological findings. Each patient initially underwent a three-phase bone scan with Tc-99m MDP (Methylene Diphosphonate) and if evidence of lesion found, the patient then underwent a dynamic and static MIBI scintigraphy after three to four days. The MDP and MIBI scans were evaluated visually and quantitatively. For quantitative analysis count ratios of lesions and contralateral normal side (L/C) were taken by region of interests drawn on scans. The Student T test was applied to assess the significant difference between benign and malignant lesions p-value < 0.05 was considered significant. Result: The MDP scans showed the increase tracer uptake, but there was no significant difference between benign and malignant uptake of the radiotracer. However significant difference (p-value 0.015), in uptake was seen in malignant (L/C = 3.51 ± 1.02) and benign lesion (L/C = 2.50±0.42) on MIBI scan. Three of thirty benign lesions did not show significant MIBI uptake. Seven malignant appeared as false negatives. Specificity of the scan was 86.66%, and its Negative Predictive Value (NPV) was 81.25% whereas the sensitivity of scan was 79.31%. In excluding the axial metastasis from the lesions, the sensitivity of MIBI scan increased to 91.66% and the NPV also increased to 92.85%. Conclusion: MIBI scintigraphy provides its usefulness by distinguishing malignant from benign lesions. MIBI also correctly identifies metastatic lesions. The negative predictive value of the scan points towards its ability to accurately diagnose the normal (benign) cases. However, biopsy remains the gold standard and a definitive diagnostic modality in musculoskeletal tumors. MIBI scan provides useful information in preoperative assessment and in distinguishing between malignant and benign lesions.

Keywords: benign, malignancies, MDP bone scan, MIBI scintigraphy

Procedia PDF Downloads 387
5798 PPB-Level H₂ Gas-Sensor Based on Porous Ni-MOF Derived NiO@CuO Nanoflowers for Superior Sensing Performance

Authors: Shah Sufaid, Hussain Shahid, Tianyan You, Liu Guiwu, Qiao Guanjun

Abstract:

Nickel oxide (NiO) is an optimal material for precise detection of hydrogen (H₂) gas due to its high catalytic activity and low resistivity. However, the gas response kinetics of H₂ gas molecules with the surface of NiO concurrence limitation imposed by its solid structure, leading to a diminished gas response value and slow electron-hole transport. Herein, NiO@CuO NFs with porous sharp-tip and nanospheres morphology were successfully synthesized by using a metal-organic framework (MOFs) as a precursor. The fabricated porous 2 wt% NiO@CuO NFs present outstanding selectivity towards H₂ gas, including a high sensitivity of a response value (170 to 20 ppm at 150 °C) higher than that of porous Ni-MOF (6), low detection limit (300 ppb) with a notable response (21), short response and recovery times at (300 ppb, 40/63 s and 20 ppm, 100/167 s), exceptional long-term stability and repeatability. Furthermore, an understanding of NiO@CuO sensor functioning in an actual environment has been obtained by using the impact of relative humidity as well. The boosted hydrogen sensing properties may be attributed due to synergistic effects of numerous facts including p-p heterojunction at the interface between NiO and CuO nanoflowers. Particularly, a porous Ni-MOF structure combined with the chemical sensitization effect of NiO with the rough surface of CuO nanosphere, are examined. This research presents an effective method for development of Ni-MOF derived metal oxide semiconductor (MOS) heterostructures with rigorous morphology and composition, suitable for gas sensing application.

Keywords: NiO@CuO NFs, metal organic framework, porous structure, H₂, gas sensing

Procedia PDF Downloads 22
5797 Ultrasonic Evaluation of Periodic Rough Inaccessible Surfaces from Back Side

Authors: Chanh Nghia Nguyen, Yu Kurokawa, Hirotsugu Inoue

Abstract:

The surface roughness is an important parameter for evaluating the quality of material surfaces since it affects functions and performance of industrial components. Although stylus and optical techniques are commonly used for measuring the surface roughness, they are applicable only to accessible surfaces. In practice, surface roughness measurement from the back side is sometimes demanded, for example, in inspection of safety-critical parts such as inner surface of pipes. However, little attention has been paid to the measurement of back surface roughness so far. Since back surface is usually inaccessible by stylus or optical techniques, ultrasonic technique is one of the most effective among others. In this research, an ultrasonic pulse-echo technique is considered for evaluating the pitch and the height of back surface having periodic triangular profile as a very first step. The pitch of the surface profile is measured by applying the diffraction grating theory for oblique incidence; then the height is evaluated by numerical analysis based on the Kirchhoff theory for normal incidence. The validity of the proposed method was verified by both numerical simulation and experiment. It was confirmed that the pitch is accurately measured in most cases. The height was also evaluated with good accuracy when it is smaller than a half of the pitch because of the approximation in the Kirchhoff theory.

Keywords: back side, inaccessible surface, periodic roughness, pulse-echo technique, ultrasonic NDE

Procedia PDF Downloads 264
5796 Hysteresis in Sustainable Two-layer Circular Tube under a Lateral Compression Load

Authors: Ami Nomura, Ken Imanishi, Etsuko Ueda, Tadahiro Wada, Shinichi Enoki

Abstract:

Recently, there have been a lot of earthquakes in Japan. It is necessary to promote seismic isolation devices for buildings. The devices have been hardly diffused in attached houses, because the devices are very expensive. We should develop a low-cost seismic isolation device for detached houses. We suggested a new seismic isolation device which uses a two-layer circular tube as a unit. If hysteresis is produced in the two-layer circular tube under lateral compression load, we think that the two-layer circular tube can have energy absorbing capacity. It is necessary to contact the outer layer and the inner layer to produce hysteresis. We have previously reported how the inner layer comes in contact with the outer layer from a perspective of analysis used mechanics of materials. We have clarified that the inner layer comes in contact with the outer layer under a lateral compression load. In this paper, we explored contact area between the outer layer and the inner layer under a lateral compression load by using FEA. We think that changing the inner layer’s thickness is effective in increase the contact area. In order to change the inner layer’s thickness, we changed the shape of the inner layer. As a result, the contact area changes depending on the inner layer’s thickness. Additionally, we experimented to check whether hysteresis occurs in fact. As a consequence, we can reveal hysteresis in the two-layer circular tube under the condition.

Keywords: contact area, energy absorbing capacity, hysteresis, seismic isolation device

Procedia PDF Downloads 282
5795 Indicators for Success of Obesity Reduction Programs in Adolescents; Body Composition and Body Mass Index: Evaluating a School-Based Health Promotion Project in Iran after 12 Weeks of Intervention

Authors: Saeid Doaei

Abstract:

Background: Obesity in adolescence is a primary risk factor for obesity in adulthood. The objective of this study was the assessment of the effect of a comprehensive lifestyle intervention on different anthropometric indices in 12 to 16 years old boy adolescents. Methods: 96 adolescent boys of two schools of District 5 of Tehran have participated in this study. The schools were randomly assigned as intervention school (n=53) and control school (n=43). The height and weight of students were measured with a calibrated tape line and digital scale respectively and their BMI were calculated. The amounts of body fat percent (BF) and body muscle (BM) percent were determined by Bio Impedance Analyzer (BIA) considering the age, gender and height of students at baseline and after intervention. The intervention was implemented in the intervention school, according to the Ottawa charter principles. Results: 12 weeks of intervention decreased body fat percent in the intervention group in comparison with the control group (decreased by 1.81 % in the intervention group and increased by .39 % in the control group, P < .01). However, weight, BMI and BM did not change significantly. Conclusion: The result of this study showed that the implementation of comprehensive intervention in obese adolescents may improve the body composition, although these changes may not be reflected in BMI. It is possible that BMI is not a good indicator in assessment of the success of obesity management intervention.

Keywords: obesity, childhood, BMI, nutrition

Procedia PDF Downloads 252
5794 Comparison of Sensitivity and Specificity of Pap Smear and Polymerase Chain Reaction Methods for Detection of Human Papillomavirus: A Review of Literature

Authors: M. Malekian, M. E. Heydari, M. Irani Estyar

Abstract:

Human papillomavirus (HPV) is one of the most common sexually transmitted infection, which may lead to cervical cancer as the main cause of it. With early diagnosis and treatment in health care services, cervical cancer and its complications are considered to be preventable. This study was aimed to compare the efficiency, sensitivity, and specificity of Pap smear and polymerase chain reaction (PCR) in detecting HPV. A literature search was performed in Google Scholar, PubMed and SID databases using the keywords 'human papillomavirus', 'pap smear' and 'polymerase change reaction' to identify studies comparing Pap smear and PCR methods for the detection. No restrictions were considered.10 studies were included in this review. All samples that were positive by pop smear were also positive by PCR. However, there were positive samples detected by PCR which was negative by pop smear and in all studies, many positive samples were missed by pop smear technique. Although The Pap smear had high specificity, PCR based HPV detection was more sensitive method and had the highest sensitivity. In order to promote the quality of detection and high achievement of the maximum results, PCR diagnostic methods in addition to the Pap smear are needed and Pap smear method should be combined with PCR techniques according to the high error rate of Pap smear in detection.

Keywords: human papillomavirus, cervical cancer, pap smear, polymerase chain reaction

Procedia PDF Downloads 118
5793 Current and Future Global Distribution of Drosophila suzukii

Authors: Yousef Naserzadeh, Niloufar Mahmoudi

Abstract:

The spotted-wing drosophila, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), a vinegar fly native to South East Asia, has recently invaded Europe, North- and South America and is spreading rapidly. Species distribution modeling has been widely employed to indicate probable areas of invasion and to guide management strategies. Drosophila sp. is native to Asia, but since 2015, it has invaded almost every country in the world, including Africa, Australia, India, and most recently, the Americas. The growth of this species of Drosophila suzukii has been rapidly multiplying and spreading in the last decade. In fact, we examine and model the potential geographical distribution of D. suzukii for both present and future scenarios. Finally, we determine the environmental variables that affect its distribution, as well as assess the risk of encroachment on protected areas. D.suzukii has the potential to expand its occurrence, especially on continents that have already been invaded. The predictive models obtained in this study indicate potential regions that could be at risk of invasion by D. suzukii, including protected areas. These results are important and can assist in the establishment of management plans to avoid the possible harm caused by biological invasions.

Keywords: climate change, Drosophila suzukii, environmental variables, host preference, host plant, nutrition

Procedia PDF Downloads 69