Search results for: Lina Tang
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 275

Search results for: Lina Tang

215 Guided Wave in a Cylinder with Trepezoid Cross-Section

Authors: Nan Tang, Bin Wu, Cunfu He

Abstract:

The trapezoid rods are widely used in civil engineering as load –carrying members. Ultrasonic guided wave is one of the most popular techniques in analyzing the propagation of elastic guided wave. The goal of this paper is to investigate the propagation of elastic waves in the isotropic bar with trapezoid cross-section. Dispersion curves that describe the relationship between the frequency and velocity provide the fundamental information to describe the propagation of elastic waves through a structure. Based on the SAFE (semi-analytical finite element) a linear algebraic system of equations is obtained. By using numerical methods, dispersion curves solved for the rods with the trapezoid cross-section. These fundamental information plays an important role in applying ultrasonic guided waves to NTD for structures with trapezoid cross section.

Keywords: guided wave, dispersion, finite element method, trapezoid rod

Procedia PDF Downloads 271
214 Application of Unmanned Aerial Vehicle in Urban Rail Transit Intelligent Inspection

Authors: Xinglu Nie, Feifei Tang, Chuntao Wei, Zhimin Ruan, Qianhong Zhu

Abstract:

Current method of manual-style inspection can not fully meet the requirement of the urban rail transit security in China. In this paper, an intelligent inspection method using unmanned aerial vehicle (UAV) is utilized. A series of orthophoto of rail transit monitored area was collected by UAV, image correction and registration were operated among multi-phase images, then the change detection was used to detect the changes, judging the engineering activities and human activities that may become potential threats to the security of urban rail. Not only qualitative judgment, but also quantitative judgment of changes in the security control area can be provided by this method, which improves the objectives and efficiency of the patrol results. The No.6 line of Chongqing Municipality was taken as an example to verify the validation of this method.

Keywords: rail transit, control of protected areas, intelligent inspection, UAV, change detection

Procedia PDF Downloads 340
213 Application of Double Side Approach Method on Super Elliptical Winkler Plate

Authors: Hsiang-Wen Tang, Cheng-Ying Lo

Abstract:

In this study, the static behavior of super elliptical Winkler plate is analyzed by applying the double side approach method. The lack of information about super elliptical Winkler plates is the motivation of this study and we use the double side approach method to solve this problem because of its superior ability on efficiently treating problems with complex boundary shape. The double side approach method has the advantages of high accuracy, easy calculation procedure and less calculation load required. Most important of all, it can give the error bound of the approximate solution. The numerical results not only show that the double side approach method works well on this problem but also provide us the knowledge of static behavior of super elliptical Winkler plate in practical use.

Keywords: super elliptical winkler plate, double side approach method, error bound, mechanic

Procedia PDF Downloads 329
212 Comprehensive Evaluation of Thermal Environment and Its Countermeasures: A Case Study of Beijing

Authors: Yike Lamu, Jieyu Tang, Jialin Wu, Jianyun Huang

Abstract:

With the development of economy and science and technology, the urban heat island effect becomes more and more serious. Taking Beijing city as an example, this paper divides the value of each influence index of heat island intensity and establishes a mathematical model – neural network system based on the fuzzy comprehensive evaluation index of heat island effect. After data preprocessing, the algorithm of weight of each factor affecting heat island effect is generated, and the data of sex indexes affecting heat island intensity of Shenyang City and Shanghai City, Beijing, and Hangzhou City are input, and the result is automatically output by the neural network system. It is of practical significance to show the intensity of heat island effect by visual method, which is simple, intuitive and can be dynamically monitored.

Keywords: heat island effect, neural network, comprehensive evaluation, visualization

Procedia PDF Downloads 111
211 Prevalence and Characteristics of Consumption of Nutraceuticals: The Case Study of Undergraduate Students of Medellin- Colombia, 2013

Authors: Gloria Inés Martínez Domínguez, Lina María Martínez Sánchez, María de los Ángeles Rodríguez Gázquez, Juan Guillermo Jiménez Jiménez, Johan Sebastián Lopera Valle, Natalia Vargas Grisales, Sara Rojas Jiménez, Alejandra Uribe Ocampo, Sara Correa Pérez, Natalia Perilla Hernández, Juan Sebastián Marín Cárdenas

Abstract:

The relationship between diet and chronic or degenerative diseases has led to the development of functional foods such as nutraceuticals. Objective: To determine the prevalence and characteristics of consumption of nutraceuticals in undergraduate students. Methodology: Cross-sectional study. It was a simple random sampling with the Statcalc EpiInfo software vr 6.04. It was designed an instrument for collection of demographic data and consumption of nutraceuticals. Statistical analysis used the SPSS program. Results: 427 students, average age 20.8 years (SD 3.1), 56.1% were women. The life prevalence of nutraceuticals consumption was 66.3% and the annual 51.8%. The main reasons for consumption were as food complement 32.8% and prevent diseases 20.1%. Conclusion: The high prevalence of nutraceuticals observed is comparable to that reported in the literature, which suggests an increasing trend in the habit of consumption of dietary supplement which have a preventive or protective effect on health.

Keywords: dietary supplements, food, health, functional food, Colombia

Procedia PDF Downloads 543
210 Garden City in the Age of ICT: A Case Study of Dali

Authors: Luojie Tang, Libin Ouyang, Yihang Gao

Abstract:

The natural landscape and urban-rural structure, with their attractiveness in the Dali area around Erhai Lake, exhibit striking similarities with Howard's Garden City. With the emergence of the unique phenomenon of the first large-scale gathering of digital nomads in China in Dali, an analysis of Dali's natural, economic, and cultural representations and structures reveals that the Garden City model can no longer fully explain the current overall human living environment in Dali. By interpreting the bottom-up local construction process in Dali based on landscape identity, the transformation of production and lifestyle under new technologies such as ICT(Information and Communication Technology), and the values and lifestyle reshaping embodied in the "reverse urbanization" phenomenon of the middle class in Dali, it is believed that Dali has moved towards a "contemporary garden city influenced by new technology." The article summarizes the characteristics and connotations of this Garden City and provides corresponding strategies for its continued healthy development.

Keywords: dali, ICT, rural-urban relationship, garden city model

Procedia PDF Downloads 47
209 Proximity-Inset Fed Triple Band Antenna for Global Position System with High Gain

Authors: The Nan Chang, Ping-Tang Yu, Jyun-Ming Lin

Abstract:

A triple band circularly polarized antenna covering 1.17, 1.22, and 1.57 GHz is presented. To extend to the triple-band operation, we need to add one more ring while maintaining the mechanism to independently control each ring. The inset-part in the feeding scheme is used to excite the band at 1.22 GHz, while the proximate-part of the feeding scheme is used to excite not only the band at 1.57 GHz but also the band at 1.17 GHz. This is achieved by up-vertically coupled with one ring to radiate at 1.57 GHz and down-vertically coupled another ring to radiate at 1.17 GHz. It is also noted that the inset-part in our feeding scheme is by horizontal coupling. Furthermore, to increase the gain at all three bands, three air-layers are added to make the total height of the antenna be 7.8 mm. The total thickness of the three air-layers is 3 mm. The gains of the three bands are all greater than 5 dBiC after adding the air-layers.

Keywords: circular polarization, global position system, high gain, triband antenna

Procedia PDF Downloads 213
208 Computational Studies of the Reactivity Descriptors and the Optoelectronic Properties on the Efficiency Free-Base- and Zn-Porphyrin-Sensitized Solar Cells

Authors: Soraya Abtouche, Zeyneb Ghoualem, Syrine Daoudi, Lina Ouldmohamed, Xavier Assfeld

Abstract:

This work reports density functional theory calculations of the optimized geometries, molecular reactivity, energy gap,and thermodynamic properties of the free base (H2P) and their Zn (II) metallated (ZnP), bearing one, two, or three carboxylic acid groups using the hybrid functional B3LYP, Cam-B3lYP, wb97xd with 6-31G(d,p) basis sets. When donating groups are attached to the molecular dye, the bond lengths are slightly decreased, which is important for the easy transfer of an electron from donating to the accepting group. For all dyes, the highest occupied molecular orbital/lowest occupied molecular orbital analysis results in positive outcomes upon electron injection to the semiconductor and subsequent dye regeneration by the electrolyte. The ionization potential increases with increasing conjugation; therefore, the compound dye attached to one carboxylic acid group has the highest ionization potential. The results show higher efficiencies of those sensitized with ZnP. These results have been explained, taking into account the electronic character of the metal ion, which acts as a mediator in the injection step, and, on the other hand, considering the number of anchoring groups to which it binds to the surface of TiO2.

Keywords: DSSC, porphyrin, TD-DFT, electronic properties, donor-acceptor groups

Procedia PDF Downloads 53
207 Biological Control of Blue Mold Disease of Grapes by Pichia anomala Supplemented by Chitosan and Its Possible Control Mechanism

Authors: Esa Abiso Godana, Qiya Yang, Kaili Wang, Zhang Hongyin, Xiaoyun Zhang, Lina Zhao

Abstract:

Blue mold decay caused by Penicillium expansum is among the recent identified diseases of grapes (Vitis vinifera). The increasing concern about use of chemical substance and pesticide in postharvest fruit push the trends of research toward biocontrol strategies which are more sustainable and ecofriendly. In this study, we determined the biocontrol efficacy of Pichia anomala alone and supplemented with 1% chitosan in the grapefruit against blue mold disease caused by P. expansum. The result showed that 1% chitosan better enhances the biocontrol efficacy P. anomala. Chitosan (1% w/v) also improved the number of population of P. anomala in grape wounds, surface and on nutrient yeast dextrose broth (NYDB). P. anomala supplemented with 1% w/v chitosan significantly reduced the disease incidence, lesion diameter and natural decay of grapefruits without affecting the fruit quality as compared to the control. The scanned electron microscope (SEM) concisely illustrates how the high number of yeast cells on the wounds reduced the growth of P. expansum. P. anomala alone or P. anomala supplemented with 1% w/v chitosan are presented as a potential biocontrol alternative against the postharvest blue mold of grapefruit.

Keywords: biocontrol, Pichia anomala, chitosan, Penicillium expansum, grape

Procedia PDF Downloads 87
206 Fifth Grade Student Skills of Reading Illustrated Drawings in Physical and Chemical Changes Included in Science Textbook

Authors: Sozan H. Omar, Lina L. Al-Rewaili

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The current study aimed to measure the fifth Grade student skills of reading illustrates in physical and chemical chapter included in science textbook, as well as identity the tasks the dispersants related to designing these illustrates which obstruct the students to read them properly. The researcher applied the test instrument of open discuss questions to measure the skill of: recognizing, description, interpretation and assessment for a sample of this research consisted of (269) students who read three illustrates, and conduct an interview with sample of them (27) students to recognize the dispersants related to designing of these illustrates. The study results showed that there are poor levels in illustrated drawing reading skills: description, interpretation, and assessment. The most important dispersants which obstruct the students to read theses illustrates properly representing: Art impacts of these illustrates, there are some elements which don’t serve these illustrates. In the light of the above results, the researcher provided some recommendations such as training the students on using the images and illustrates properly in science textbooks, as well as create simple designs of illustrates and they should be free of crowded elements and impacts which don’t serve the illustrates.

Keywords: reading illustrated drawings skills, fifth grade science, physical and chemical changes

Procedia PDF Downloads 351
205 Comparison of the Performance of GaInAsSb and GaSb Cells under Different Temperature Blackbody Radiations

Authors: Liangliang Tang, Chang Xu, Xingying Chen

Abstract:

GaInAsSb cells probably show better performance than GaSb cells in low-temperature thermophotovoltaic systems due to lower bandgap; however, few experiments proved this phenomenon so far. In this paper, numerical simulation is used to evaluate GaInAsSb and GaSb cells with similar structures under different radiation temperatures. We found that GaInAsSb cells with n-type emitters show slightly higher output power densities compared with that of GaSb cells with n-type emitters below 1,550 K-blackbody radiation, and the power density of the later cells will suppress the formers above this temperature point. During the temperature range of 1,000~2,000 K, the efficiencies of GaSb cells are about twice of GaInAsSb cells if perfect filters are used to prevent the emission of the non-absorbed long wavelength photons. Several parameters that affect the GaInAsSb cell were analyzed, such as doping profiles, thicknesses of GaInAsSb epitaxial layer and surface recombination velocity. The non-p junctions, i.e., n-type emitters are better for GaInAsSb cell fabrication, which is similar to that of GaSb cells.

Keywords: thermophotovoltaic cell, GaSb, GaInAsSb, diffused emitters

Procedia PDF Downloads 248
204 Altered L-Type Calcium Channel Activity in Atrioventricular Nodal Myocytes from Rats with Streptozotocin-Induced Type I Diabetes Mellitus

Authors: Kathryn H. Yull, Lina T. Al Kury, Frank Christopher Howarth

Abstract:

Cardiovascular diseases are frequently reported in patients with Type-1 Diabetes mellitus (DM). In addition to changes in cardiac muscle inotropy, electrical abnormalities are also commonly observed in these patients. In the present study, using streptozotocin (STZ) rat model of Type-1 DM, we have characterized the changes in L-type calcium channel activity in single atrioventricular nodal (AVN) myocytes. Ionic currents were recorded from AVN myocytes isolated from the hearts of control rats and from those with STZ-induced diabetes. Patch-clamp recordings were used to assess changes in cellular electrical activity in individual myocytes. Type-1 DM significantly altered the cellular characteristics of L-type calcium current (ICaL). A reduction in peak ICaL density was observed, with no corresponding changes in the activation parameters of the current. ICaL also exhibited faster time-dependent inactivation in AVN myocytes from diabetic rats. A negative shift in the voltage dependence of inactivation was also evident. These findings demonstrate that experimentally–induced type-1 DM significantly alters AVN L-type calcium channel cellular electrophysiology. The changes in ion channel activity may underlie the abnormalities in the cardiac electrical function that contribute to the high mortality levels in patients with DM.

Keywords: cardiac, ion-channel, diabetes, atrioventricular node, calcium channel

Procedia PDF Downloads 314
203 Synthesis of Carboxylate Gemini Surfactant

Authors: Rui Wang, Shanfa Tang, Yuanwu Dong, Siyao Wang

Abstract:

A carboxylate Gemini surfactant N, N`-bis (3-chloro-2 -hydroxypropane-N-dodecyl secondary amine) p-phenylenediamine diacetate sodium (GD12-P-12) was synthesized by substitution and ring-opening reaction from p-phenylenediamine, sodium chloroacetate, epichlorohydrin, and dodecylamine. The synthesis conditions were optimized by controlling variables. The structure of GD12-P-12 was characterized by FT-IR and 1H NMR, and its foam performance, interfacial tension, viscosity was evaluated. The results show that the molecular structure of the synthesized product is consistent with that of the target product, the GD12-P-12 can reduce the oil-water interfacial tension to 7.49×10⁻³mN/m (ultra-low interfacial tension level) in 20min. GD12-P-12 surfactant has excellent foam performance, ultra-low interfacial tension, good temperature-resistant viscosity-increasing properties, has good application prospect in foam flooding.

Keywords: gemini surfactant, optimization of synthesis conditions, foam performance, low interfacial tension

Procedia PDF Downloads 98
202 Embodied Spiritualities and Emerging Search for Social Transformation: An Embodied Ethnographic Study of Yoga Practices in Medellin, Colombia

Authors: Lina M. Vidal

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This paper discusses yoga practices involvement in both self-transformation and social transformations by means of an embodied ethnographic approach to different initiatives for social change in Medellín. In the context of gradual popularization of embodied spiritualities, yoga practices have opened their way in calls for social change in a performative perspective which involves collective experiences, reflections and production of embodied knowledge. Through the reflection on bodily dimension and corporal experience, this ethnographic approach acknowledges inter-corporality and somatic modes of attention during observations and personal experiences. In social change initiatives that include yoga practices were identified transformations of common understanding on social issues such as it is produced by institutionalized education, health system and other fields of knowledge. This is clearly visible in yoga projects for children in vulnerable conditions, homeless people, prisoners, and young people recovering from drug addiction. These projects are often promoted by organizations and networks, which incorporate individual life stories into collective experiences. Dissemination of yoga is heading to a broad institutional and cultural legitimation of yoga and of spirituality that impact different fields of social work and everyday life in general. This way, yoga is becoming an embodied activist way of life and a legitimate field for social work.

Keywords: embodied ethnography, Medellin, social transformation, embodied spiritualities, yoga practices

Procedia PDF Downloads 160
201 Establishing Quality Evaluation Indicators of Early Education Center for 0~3 Years Old

Authors: Lina Feng

Abstract:

The study aimed at establishing quality evaluation indicators of an early education center for 0~3 years old, and defining the weight system of it. Expert questionnaire and Fuzzy Delphi method were applied. Firstly, in order to ensure the indicators in accordance with the practice of early education, 16 experts were invited as respondents to a preliminary Expert Questionnaire about Quality Evaluation Indicators of Early Education Center for 0~3 Years Old. The indicators were based on relevant studies on quality evaluation indicators of early education centers in China and abroad. Secondly, 20 scholars, kindergarten principals, and educational administrators were invited to form a fuzzy Delphi expert team. The experts’ opinions on the importance of indicators were calculated through triangle fuzzy numbers in order to select appropriate indicators and calculate indicator weights. This procedure resulted in the final Quality Evaluation Indicators of Early education Center for 0~3 Years Old. The Indicators contained three major levels, including 6 first-level indicators, 30 second-level indicators, and 147 third-level indicators. The 6 first-level indicators were health and safety; educational and cultivating activities; development of babies; conditions of the center; management of the center; and collaboration between family and the community. The indicators established by this study could provide suggestions for the high-quality environment for promoting the development of early year children.

Keywords: early education center for 0~3 years old, educational management, fuzzy delphi method, quality evaluation indicator

Procedia PDF Downloads 234
200 Out of Pocket Costs for Patients with Tuberculosis in Colombia: Evidence from Three Metropolitan Areas

Authors: Jose Hernandez, Lina Martínez, Gustavo Gonzalez, Carlos Lázaro, Diana Castrillon, Jonathan Cardona, Laura Mejía, Yina Sanchez, Luisa Ochoa, Evert Jimenez

Abstract:

Objectives: Economic analyses of tuberculosis control interventions are usually focused on the payer’s perspective. To assess the overall economic impact of the disease, out-of-pocket and indirect costs are also required. This research is aimed to estimate overall economic impact under DOTS-strategy (Directly Observed Therapy Short Course). Methods: A cross-sectional survey of 91 adult tuberculosis patients in treatment for at least two months was conducted from the society perspective. A standardized questionnaire was used in three different cities of Colombia: Medellin (poverty is 17.7%), Monteria (poverty is 36.9%) and Quibdó (poverty is 51.2%). Costs were converted to 2013 USD and categorized into two periods: diagnostics phase and treatment. Results: The median cost during diagnostics was 13$ (±SD 9.5). The median monthly patient out-of-pocket costs during treatment were 32$ (±SD 6.8), equivalent to 17% of patient’s median monthly income, estimated in 186$ (±SD 23). Costs recorded in Medellin were 47$ in Monteria was 18$ and in Quibdó was 13$. Conclusion: Patient costs under DOTS strategy are high even when services are provided free of charge. The creation or strengthening of community-based treatment supervisors could greatly impact costs of tuberculosis and lower drop-outs.

Keywords: tuberculosis, costs and cost analysis, health promotion, Colombia

Procedia PDF Downloads 342
199 Methods Used to Perform Requirements Elicitation for Healthcare Software Development

Authors: Tang Jiacheng, Fang Tianyu, Liu Yicen, Xiang Xingzhou

Abstract:

The proportion of healthcare services is increasing throughout the globe. The convergence of mobile technology is driving new business opportunities, innovations in healthcare service delivery and the promise of a better life tomorrow for different populations with various healthcare needs. One of the most important phases for the combination of health care and mobile applications is to elicit requirements correctly. In this paper, four articles from different research directions with four topics on healthcare were detailed analyzed and summarized. We identified the underlying problems in guidance to develop mobile applications to provide healthcare service for Older adults, Women in menopause, Patients undergoing covid. These case studies cover several elicitation methods: survey, prototyping, focus group interview and questionnaire. And the effectiveness of these methods was analyzed along with the advantages and limitations of these methods, which is beneficial to adapt the elicitation methods for future software development process.

Keywords: healthcare, software requirement elicitation, mobile applications, prototyping, focus group interview

Procedia PDF Downloads 116
198 Relationship between the Ability of Accruals and Non-Systematic Risk of Shares for Companies Listed in Stock Exchange: Case Study, Tehran

Authors: Lina Najafian, Hamidreza Vakilifard

Abstract:

The present study focused on the relationship between the quality of accruals and non-systematic risk. The independent study variables included the ability of accruals, the information content of accruals, and amount of discretionary accruals considered as accruals quality measures. The dependent variable was non-systematic risk based on the Fama and French Three Factor model (FFTFM) and the capital asset pricing model (CAPM). The control variables were firm size, financial leverage, stock return, cash flow fluctuations, and book-to-market ratio. The data collection method was based on library research and document mining including financial statements. Multiple regression analysis was used to analyze the data. The study results showed that there is a significant direct relationship between financial leverage and discretionary accruals and non-systematic risk based on FFTFM and CAPM. There is also a significant direct relationship between the ability of accruals, information content of accruals, firm size, and stock return and non-systematic based on both models. It was also found that there is no relationship between book-to-market ratio and cash flow fluctuations and non-systematic risk.

Keywords: accruals quality, non-systematic risk, CAPM, FFTFM

Procedia PDF Downloads 138
197 Fast Fourier Transform-Based Steganalysis of Covert Communications over Streaming Media

Authors: Jinghui Peng, Shanyu Tang, Jia Li

Abstract:

Steganalysis seeks to detect the presence of secret data embedded in cover objects, and there is an imminent demand to detect hidden messages in streaming media. This paper shows how a steganalysis algorithm based on Fast Fourier Transform (FFT) can be used to detect the existence of secret data embedded in streaming media. The proposed algorithm uses machine parameter characteristics and a network sniffer to determine whether the Internet traffic contains streaming channels. The detected streaming data is then transferred from the time domain to the frequency domain through FFT. The distributions of power spectra in the frequency domain between original VoIP streams and stego VoIP streams are compared in turn using t-test, achieving the p-value of 7.5686E-176 which is below the threshold. The results indicate that the proposed FFT-based steganalysis algorithm is effective in detecting the secret data embedded in VoIP streaming media.

Keywords: steganalysis, security, Fast Fourier Transform, streaming media

Procedia PDF Downloads 121
196 Surface Nanocrystalline and Hardening Effects of Ti–Al–V Alloy by Electropulsing Ultrasonic Shock

Authors: Xiaoxin Ye, Guoyi Tang

Abstract:

The effect of electropulsing ultrasonic shock (EUS) on the surface hardening and microstructure of Ti6Al4V alloy was studied. It was found that electropulsing improved the microhardness dramatically both in the influential depth and maximum value, compared with the only ultrasonic-shocked sample. It’s indicated that refined surface layer with nanocrystalline and improved microhardness were obtained on account of surface severe plastic deformation, dynamic recrystallization (DRX) and phase change, which was implemented at relative low temperature and high strain rate/capacity due to the coupling of the thermal and athermal effects of EUS. It’s different from conventional experiments and theory. It’s discussed that the positive contributions of EPT in the thermodynamics and kinetics of microstructure and properties change were attributed to the reduction of nucleation energy barrier and acceleration of atomic diffusion. Therefore, it’s supposed that EUS is an energy-saving and high-efficiency method of surface treatment technique with the help of high-energy electropulses, which is promising in cost reduction of the surface engineering and energy management.

Keywords: titanium alloys, electropulsing, ultrasonic shock, microhardness, nanocrystalline

Procedia PDF Downloads 268
195 Robust Attitude Control for Agile Satellites with Vibration Compensation

Authors: Jair Servín-Aguilar, Yu Tang

Abstract:

We address the problem of robust attitude tracking for agile satellites under unknown bounded torque disturbances using a double-gimbal variable-speed control-moment gyro (DGVSCMG) driven by a cluster of three permanent magnet synchronous motors (PMSMs). Uniform practical asymptotic stability is achieved at the torque control level first. The desired speed of gimbals and the acceleration of the spin wheel to produce the required torque are then calculated by a velocity-based steering law and tracked at the PMSM speed-control level by designing a speed-tracking controller with compensation for the vibration caused by eccentricity and imbalance due to mechanical imperfection in the DGVSCMG. Uniform practical asymptotic stability of the overall system is ensured by loan relying on the analysis of the resulting cascaded system. Numerical simulations are included to show the performance improvement of the proposed controller.

Keywords: agile satellites, vibration compensation, internal model, stability

Procedia PDF Downloads 90
194 Assessing Relationships between Glandularity and Gray Level by Using Breast Phantoms

Authors: Yun-Xuan Tang, Pei-Yuan Liu, Kun-Mu Lu, Min-Tsung Tseng, Liang-Kuang Chen, Yuh-Feng Tsai, Ching-Wen Lee, Jay Wu

Abstract:

Breast cancer is predominant of malignant tumors in females. The increase in the glandular density increases the risk of breast cancer. BI-RADS is a frequently used density indicator in mammography; however, it significantly overestimates the glandularity. Therefore, it is very important to accurately and quantitatively assess the glandularity by mammography. In this study, 20%, 30% and 50% glandularity phantoms were exposed using a mammography machine at 28, 30 and 31 kVp, and 30, 55, 80 and 105 mAs, respectively. The regions of interest (ROIs) were drawn to assess the gray level. The relationship between the glandularity and gray level under various compression thicknesses, kVp, and mAs was established by the multivariable linear regression. A phantom verification was performed with automatic exposure control (AEC). The regression equation was obtained with an R-square value of 0.928. The average gray levels of the verification phantom were 8708, 8660 and 8434 for 0.952, 0.963 and 0.985 g/cm3, respectively. The percent differences of glandularity to the regression equation were 3.24%, 2.75% and 13.7%. We concluded that the proposed method could be clinically applied in mammography to improve the glandularity estimation and further increase the importance of breast cancer screening.

Keywords: mammography, glandularity, gray value, BI-RADS

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193 Ti-Mo-N Nano-Grains Embedded into Thin MoSₓ-Based Amorphous Matrix: A Novel Structure for Superhardness and Ultra-Low Wear

Authors: Lina Yang, Mao Wen, Jianhong Chen, Kan Zhang

Abstract:

Molybdenum disulfide (MoS₂) represents a highly sought lubricant for reducing friction based on intrinsic layered structure, but for this reason, practical applications have been greatly restricted due to the fact that its low hardness would cause severe wear. Here, a novel TiMoN/MoSₓ composite coatings with TiMoN solid solution grains embedded into MoSₓ-based amorphous matrix has been successfully designed and synthesized, through magnetron co-sputtering technology. Desirably, in virtue of such special microstructure, superhardness and excellent toughness can be well achieved, along with an ultra-low wear rate at ~2×10⁻¹¹ mm³/Nm in the air environment, simultaneously, low friction at ~0.1 is maintained. It should be noted that this wear level is almost two orders of magnitude lower than that of pure TiN coating, and is, as we know, the lowest wear rate in dry sliding. Investigations of tribofilm reveal that it is amorphous MoS₂ in nature, and its formation arises directly from the MoSₓ amorphous matrix. Which contributes to effective lubrication behavior, coupled with excellent mechanical performances of such composite coating, exceptionally low wear can be guaranteed. The findings in this work suggest that the special composite structure makes it possible for the synthesis of super-hard and super-durable lubricative coating, offering guidance to synthesize ultrahigh performance protective coating for industrial application.

Keywords: hardness, MoS₂-containing composite coatings, toughness, tribological properties

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192 Spin-Dependent Transport Signatures of Bound States: From Finger to Top Gates

Authors: Yun-Hsuan Yu, Chi-Shung Tang, Nzar Rauf Abdullah, Vidar Gudmundsson

Abstract:

Spin-orbit gap feature in energy dispersion of one-dimensional devices is revealed via strong spin-orbit interaction (SOI) effects under Zeeman field. We describe the utilization of a finger-gate or a top-gate to control the spin-dependent transport characteristics in the SOI-Zeeman influenced split-gate devices by means of a generalized spin-mixed propagation matrix method. For the finger-gate system, we find a bound state in continuum for incident electrons within the ultra-low energy regime. For the top-gate system, we observe more bound-state features in conductance associated with the formation of spin-associated hole-like or electron-like quasi-bound states around band thresholds, as well as hole bound states around the reverse point of the energy dispersion. We demonstrate that the spin-dependent transport behavior of a top-gate system is similar to that of a finger-gate system only if the top-gate length is less than the effective Fermi wavelength.

Keywords: spin-orbit, zeeman, top-gate, finger-gate, bound state

Procedia PDF Downloads 241
191 Expounding on the Role of Sustainability Values (SVs) on Consumers’ Switching Intentions Regarding Disruptive 5G Technology in China

Authors: Sayed Kifayat Shah, Tang Zhongjun, Mohammad Ahmad, Sohaib Mostafa

Abstract:

This article investigates consumer’s intention to shift to 5G in the light of disruptive technology innovation. To switch from 4G (Existing) technology to 5G (Disruptive) technology requires not just economic benefits and costs but involves other values too, which aren't yet experienced in the framework of technology innovation. This study extended the valued adaptation (VAM) model by proposing the sustainability values (SVs) construct. The model was examined on data from 361 Chinese consumers using the partial least squares-based structural equation modelling (PLS-SEM) technique. The outcomes prove the significant correlation of sustainability values (SVs) which influences consumer’s switching intentions toward 5G disruptive technology. The findings of this research will be helpful to telecoms firms in developing consumer retention strategies. Some limitations and the importance of the research for scholars and managers are also discussed.

Keywords: value adaptation model (VAM), sustainability values (SVs), disruptive 5G technology, switching intentions (SI), partial least squares-based structural equation modelling (PLS-SEM)

Procedia PDF Downloads 122
190 Examining First-time Remote Workers’ Perceptions on Work From Home Amidst the COVID-19 Pandemic: The Future Potential of Hybrid Work Mode

Authors: Lina Vyas, Stuti Rawat

Abstract:

The COVID-19 outbreak has forced many employees to extensively adopt remote work or, widely known as work from home (WFH) arrangements. During the last two years, both employers and employees have had the opportunity to be increasingly aware of the benefits and drawbacks of WFH. Likewise, it gained the attention of academics from various schools of thought who have been interested in the future of work practices and work-life balance. Additionally, employees might also have various demands regarding their work practices after the pandemic. This study explores the potential of hybrid ways of working in the post-pandemic period by comparing first-timers who (sometimes or always) worked from home during the pandemic with those who did not, in terms of the aspects of work-life balance, work-life interference, job performance and willingness to work from home after the pandemic. The quantitative research approach was adopted. Data were collected via an online questionnaire from employees working from home in Hong Kong during the pandemic. There were one thousand three hundred and twenty-eight responses, but only 1,235 respondents experienced working from home during the pandemic. The findings reveal that 72.2% never had or hardly experienced work from home prior to the pandemic. There were statistically significant differences between first-timers and non-first-timers in work-life balance and work-life interference. The study also found that first-timers who were always working from home during the pandemic would prefer having longer WFH after the pandemic than those who were sometimes working from home. These results would serve as a basis for policy development, enabling policymakers to design appropriate HR policies and amend them to meet the current context of actual employee needs.

Keywords: hybrid working mode, remote working, work from home, work-life balance, workplace

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189 Heat Waves Effect on Stock Return and Volatility: Evidence from Stock Market and Selected Industries in Pakistan

Authors: Sayed Kifayat Shah, Tang Zhongjun, Arfa Tanveer

Abstract:

This study explores the significant heatwave effect on stock return and volatility. Using an ARCH/GARCH approach, it examines the relationship between the heatwave of Karachi, Islamabad, and Lahore on the KSE-100 index. It also explores the impact of heatwave on returns of the pharmaceutical and electronics industries. The empirical results confirm that that stock return is positively related to the heat waves of Karachi, negatively related to that of Islamabad, and is not affected by the heatwave of Lahore. Similarly, pharmaceutical and electronics indices are also positively related to heatwaves. These differences in results can be ascribed to the change in the behavior of the residents of that city. The outcomes are useful for understanding an investor's behavior reacting to weather and fluxes in stock price related to heatwave severity levels. The results can support investors in fixing biases in behavior.

Keywords: ARCH/GARCH model, heat wave, KSE-100 index, stock market return

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188 The Mechanism of Upgrading and Urban Development in the Egyptian City: Case Study of Damietta

Authors: Lina Fayed Amin

Abstract:

The research studied, in the beginning, the related urban concepts such as the urban, development, urban development. As it also deals with the upgrading, urban upgrading, community participation and the role of local administration in development and upgrading projects. Then it studies some regional upgrading & urban development projects in Egypt followed by international projects, and the analysis the strategies followed in dealing with these projects. Afterwards, we state the regional aspects of both Damietta governorate & city, dealing with its potentials & development constraints. Followed by studying the upgrading and urban development projects strategies in reflection to the city’s crucial problems, and the constraints that faced the upgrading & development project. Then, it studied the implementation of the project’s strategies & it provided the financial resources needed for the development project in Damietta city. Followed by the studying of the urban and human development projects in the upgrading of Damietta city, as well as analyzing the different projects &analyzing the results of these projects on the aspects of the city’s needs. Then the research analysis in comparison the upgrading and urban development project in Damietta and the regional upgrading and development projects in Egypt. As well as the comparison between the upgrading and urban development project and the international projects in some Arabic and foreign countries in relation to the goals, problems, obstacles, the community participation, the finance resources and the results. Finally, it reviews the results and recommendations that were reached as a result of studying the similar urban upgrading projects in Egypt and in some Arabic and foreign countries. Followed by the analytical analysis of the upgrading and urban development in Egypt

Keywords: Damietta city, urban development, upgrading mechanisms, urban upgrading

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187 Design of Quality Assessment System for On-Orbit 3D Printing Based on 3D Reconstruction Technology

Authors: Jianning Tang, Trevor Hocksun Kwan, Xiaofeng Wu

Abstract:

With the increasing demand for space use in multiple sectors (navigation, telecommunication, imagery, etc.), the deployment and maintenance demand of satellites are growing. Considering the high launching cost and the restrictions on weight and size of the payload when using launch vehicle, the technique of on-orbit manufacturing has obtained more attention because of its significant potential to support future space missions. 3D printing is the most promising manufacturing technology that could be applied in space. However, due to the lack of autonomous quality assessment, the operation of conventional 3D printers still relies on human presence to supervise the printing process. This paper is proposed to develop an automatic 3D reconstruction system aiming at detecting failures on the 3D printed objects through application of point cloud technology. Based on the data obtained from the point cloud, the 3D printer could locate the failure and repair the failure. The system will increase automation and provide 3D printing with more feasibilities for space use without human interference.

Keywords: 3D printing, quality assessment, point cloud, on-orbit manufacturing

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186 Metaphor Institutionalization as Phase Transition: Case Studies of Chinese Metaphors

Authors: Xuri Tang, Ting Pan

Abstract:

Metaphor institutionalization refers to the propagation of a metaphor that leads to its acceptance in speech community as a norm of the language. Such knowledge is important to both theoretical studies of metaphor and practical disciplines such as lexicography and language generation. This paper reports an empirical study of metaphor institutionalization of 14 Chinese metaphors. It first explores the pattern of metaphor institutionalization by fitting the logistic function (or S-shaped curve) to time series data of conventionality of the metaphors that are automatically obtained from a large-scale diachronic Chinese corpus. Then it reports a questionnaire-based survey on the propagation scale of each metaphor, which is measured by the average number of subjects that can easily understand the metaphorical expressions. The study provides two pieces of evidence supporting the hypothesis that metaphor institutionalization is a phrase transition: (1) the pattern of metaphor institutionalization is an S-shaped curve and (2) institutionalized metaphors generally do not propagate to the whole community but remain in equilibrium state. This conclusion helps distinguish metaphor institutionalization from topicalization and other types of semantic change.

Keywords: metaphor institutionalization, phase transition, propagation scale, s-shaped curve

Procedia PDF Downloads 150