Search results for: microstructure and mechanical properties relationship
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 16590

Search results for: microstructure and mechanical properties relationship

6450 Biomimetic Dinitrosyl Iron Complexes: A Synthetic, Structural, and Spectroscopic Study

Authors: Lijuan Li

Abstract:

Nitric oxide (NO) has become a fascinating entity in biological chemistry over the past few years. It is a gaseous lipophilic radical molecule that plays important roles in several physiological and pathophysiological processes in mammals, including activating the immune response, serving as a neurotransmitter, regulating the cardiovascular system, and acting as an endothelium-derived relaxing factor. NO functions in eukaryotes both as a signal molecule at nanomolar concentrations and as a cytotoxic agent at micromolar concentrations. The latter arises from the ability of NO to react readily with a variety of cellular targets leading to thiol S-nitrosation, amino acid N-nitrosation, and nitrosative DNA damage. Nitric oxide can readily bind to metals to give metal-nitrosyl (M-NO) complexes. Some of these species are known to play roles in biological NO storage and transport. These complexes have different biological, photochemical, or spectroscopic properties due to distinctive structural features. These recent discoveries have spawned a great interest in the development of transition metal complexes containing NO, particularly its iron complexes that are central to the role of nitric oxide in the body. Spectroscopic evidence would appear to implicate species of “Fe(NO)2+” type in a variety of processes ranging from polymerization, carcinogenesis, to nitric oxide stores. Our research focuses on isolation and structural studies of non-heme iron nitrosyls that mimic biologically active compounds and can potentially be used for anticancer drug therapy. We have shown that reactions between Fe(NO)2(CO)2 and a series of imidazoles generated new non-heme iron nitrosyls of the form Fe(NO)2(L)2 [L = imidazole, 1-methylimidazole, 4-methylimidazole, benzimidazole, 5,6-dimethylbenzimidazole, and L-histidine] and a tetrameric cluster of [Fe(NO)2(L)]4 (L=Im, 4-MeIm, BzIm, and Me2BzIm), resulted from the interactions of Fe(NO)2 with a series of substituted imidazoles was prepared. Recently, a series of sulfur bridged iron di nitrosyl complexes with the general formula of [Fe(µ-RS)(NO)2]2 (R = n-Pr, t-Bu, 6-methyl-2-pyridyl, and 4,6-dimethyl-2-pyrimidyl), were synthesized by the reaction of Fe(NO)2(CO)2 with thiols or thiolates. Their structures and properties were studied by IR, UV-vis, 1H-NMR, EPR, electrochemistry, X-ray diffraction analysis and DFT calculations. IR spectra of these complexes display one weak and two strong NO stretching frequencies (νNO) in solution, but only two strong νNO in solid. DFT calculations suggest that two spatial isomers of these complexes bear 3 Kcal energy difference in solution. The paramagnetic complexes [Fe2(µ-RS)2(NO)4]-, have also been investigated by EPR spectroscopy. Interestingly, the EPR spectra of complexes exhibit an isotropic signal of g = 1.998 - 2.004 without hyperfine splitting. The observations are consistent with the results of calculations, which reveal that the unpaired electron dominantly delocalize over the two sulfur and two iron atoms. The difference of the g values between the reduced form of iron-sulfur clusters and the typical monomeric di nitrosyl iron complexes is explained, for the first time, by of the difference in unpaired electron distributions between the two types of complexes, which provides the theoretical basis for the use of g value as a spectroscopic tool to differentiate these biologically active complexes.

Keywords: di nitrosyl iron complex, metal nitrosyl, non-heme iron, nitric oxide

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6449 Persian Pistachio Nut (Pistacia vera L.) Dehydration in Natural and Industrial Conditions

Authors: Hamid Tavakolipour, Mohsen Mokhtarian, Ahmad Kalbasi Ashtari

Abstract:

In this study, the effect of various drying methods (sun drying, shade drying and industrial drying) on final moisture content, shell splitting degree, shrinkage and color change were studied. Sun drying resulted higher degree of pistachio nuts shell splitting on pistachio nuts relative other drying methods. The ANOVA results showed that the different drying methods did not significantly effects on color change of dried pistachio nut. The results illustrated that pistachio nut dried by industrial drying had the lowest moisture content. After the end of drying process, initially, the experimental drying data were fitted with five famous drying models namely Newton, Page, Silva et al., Peleg and Henderson and Pabis. The results indicated that Peleg and Page models gave better results compared with other models to monitor the moisture ratio’s pistachio nut in industrial drying and open sun (or shade drying) methods, respectively.

Keywords: industrial drying, pistachio, quality properties, traditional drying

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6448 Geomorphology Evidence of Climate Change in Gavkhouni Lagoon, South East Isfahan, Iran

Authors: Manijeh Ghahroudi Tali, Ladan Khedri Gharibvand

Abstract:

Gavkhouni lagoon, in the South East of Isfahan (Iran), is one of the pluvial lakes and legacy of Quaternary era which has emerged during periods with more precipitation and less evaporation. Climate change, lack of water resources and dried freshwater of Zayandehrood resulted in increased entropy and activated a dynamic which in turn is converted to Playa. The morphometry of 61 polygonal clay microforms in wet zone soil, 52 polygonal clay microforms in pediplain zone soil and 63 microforms in sulfate soil, is evaluated by fractal model. After calculating the microforms’ area–perimeter fractal dimension, their turbulence level was analyzed. Fractal dimensions (DAP) obtained from the microforms’ analysis of pediplain zone, wet zone, and sulfate soils are 1/21-1/39, 1/27-1/44 and 1/29-1/41, respectively, which is indicative of turbulence in these zones. Logarithmic graph drawn for each region also shows that there is a linear relationship between logarithm of the microforms’ area and perimeter so that correlation coefficient (R2) obtained for wet zone is larger than 0.96, for pediplain zone is larger than 0.99 and for sulfated zone is 0.9. Increased turbulence in this region suggests morphological transformation of the system and lagoon’s conversion to a new ecosystem which can be accompanied with serious risks.

Keywords: fractal, Gavkhouni, microform, Iran

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6447 Cotton Crops Vegetative Indices Based Assessment Using Multispectral Images

Authors: Muhammad Shahzad Shifa, Amna Shifa, Muhammad Omar, Aamir Shahzad, Rahmat Ali Khan

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Many applications of remote sensing to vegetation and crop response depend on spectral properties of individual leaves and plants. Vegetation indices are usually determined to estimate crop biophysical parameters like crop canopies and crop leaf area indices with the help of remote sensing. Cotton crops assessment is performed with the help of vegetative indices. Remotely sensed images from an optical multispectral radiometer MSR5 are used in this study. The interpretation is based on the fact that different materials reflect and absorb light differently at different wavelengths. Non-normalized and normalized forms of these datasets are analyzed using two complementary data mining algorithms; K-means and K-nearest neighbor (KNN). Our analysis shows that the use of normalized reflectance data and vegetative indices are suitable for an automated assessment and decision making.

Keywords: cotton, condition assessment, KNN algorithm, clustering, MSR5, vegetation indices

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6446 Effects of Heat Treatment on the Elastic Constants of Cedar Wood

Authors: Tugba Yilmaz Aydin, Ergun Guntekin, Murat Aydin

Abstract:

Effects of heat treatment on the elastic constants of cedar wood (Cedrus libani) were investigated. Specimens were exposed to heat under atmospheric pressure at four different temperatures (120, 150, 180, 210 °C) and three different time levels (2, 5, 8 hours). Three Young’s modulus (EL, ER, ET) and six Poisson ratios (μLR, μLT, μRL, μRT, μTL, μTR) were determined from compression test using bi-axial extensometer at constant moisture content (12 %). Three shear modulus were determined using ultrasound. Six shear wave velocities propagating along the principal axes of anisotropy were measured using EPOCH 650 ultrasonic flaw detector with 1 MHz transverse transducers. The properties of the samples tested were significantly affected by heat treatment by different degree. As a result, softer treatments yielded some amount of increase in Young modulus and shear modulus values, but increase of time and temperature resulted in significant decrease for both values. Poisson ratios seemed insensitive to heat treatment.

Keywords: cedar wood, elastic constants, heat treatment, ultrasound

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6445 Porosity Characterization and Its Destruction by Authigenic Minerals: Reservoir Sandstones, Mamuniyat Formation, Murzuq Basin, SW Libya

Authors: Mohamrd Ali Alrabib

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Sandstones samples were selected from cores of seven wells ranging in depth from 5040 to 7181.4 ft. The dominant authigenic cement phase is quartz overgrowth cement (up to 13% by volume) and this is the major mechanism for porosity reduction. Late stage carbonate cements (siderite and dolomite/ferroan dolomite) are present and these minerals infill intergranular porosity and, therefore, further reduce porosity and probably permeability. Authigenic clay minerals are represented by kaolinite, illite, and grain coating clay minerals. Kaolinite occurs as booklet and vermicular forms. Minor amounts of illite were noted in the studied samples, which commonly block pore throats, thereby reducing permeability. Primary porosity of up to 26.5% is present. Secondary porosity (up to 17%) is also present as a result of feldspar dissolution. The high intergranular volume (IGV) of the sandstones indicates that mechanical and chemical compaction played a more important role than cementation of porosity loss.

Keywords: authigenic minerals, porosity types, porosity reduction, mamuniyat sandstone reservoir

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6444 Using Heat-Mask in the Thermoforming Machine for Component Positioning in Thermoformed Electronics

Authors: Behnam Madadnia

Abstract:

For several years, 3D-shaped electronics have been rising, with many uses in home appliances, automotive, and manufacturing. One of the biggest challenges in the fabrication of 3D shape electronics, which are made by thermoforming, is repeatable and accurate component positioning, and typically there is no control over the final position of the component. This paper aims to address this issue and present a reliable approach for guiding the electronic components in the desired place during thermoforming. We have proposed a heat-control mask in the thermoforming machine to control the heating of the polymer, not allowing specific parts to be formable, which can assure the conductive traces' mechanical stability during thermoforming of the substrate. We have verified our approach's accuracy by applying our method on a real industrial semi-sphere mold for positioning 7 LEDs and one touch sensor. We measured the LEDs' position after thermoforming to prove the process's repeatability. The experiment results demonstrate that the proposed method is capable of positioning electronic components in thermoformed 3D electronics with high precision.

Keywords: 3D-shaped electronics, electronic components, thermoforming, component positioning

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6443 Transport of Reactive Carbo-Iron Composite Particles for in situ Groundwater Remediation Investigated at Laboratory and Field Scale

Authors: Sascha E. Oswald, Jan Busch

Abstract:

The in-situ dechlorination of contamination by chlorinated solvents in groundwater via zero-valent iron (nZVI) is potentially an efficient and prompt remediation method. A key requirement is that nZVI has to be introduced in the subsurface in a way that substantial quantities of the contaminants are actually brought into direct contact with the nZVI in the aquifer. Thus it could be a more flexible and precise alternative to permeable reactive barrier techniques using granular iron. However, nZVI are often limited by fast agglomeration and sedimentation in colloidal suspensions, even more so in the aquifer sediments, which is a handicap for the application to treat source zones or contaminant plumes. Colloid-supported nZVI show promising characteristics to overcome these limitations and Carbo-Iron Colloids is a newly developed composite material aiming for that. The nZVI is built onto finely ground activated carbon of about a micrometer diameter acting as a carrier for it. The Carbo-Iron Colloids are often suspended with a polyanionic stabilizer, and carboxymethyl cellulose is one with good properties for that. We have investigated the transport behavior of Carbo-Iron Colloids (CIC) on different scales and for different conditions to assess its mobility in aquifer sediments as a key property for making its application feasible. The transport properties were tested in one-dimensional laboratory columns, a two-dimensional model aquifer and also an injection experiment in the field. Those experiments were accompanied by non-invasive tomographic investigations of the transport and filtration processes of CIC suspensions. The laboratory experiments showed that a larger part of the CIC can travel at least scales of meters for favorable but realistic conditions. Partly this is even similar to a dissolved tracer. For less favorable conditions this can be much smaller and in all cases a particular fraction of the CIC injected is retained mainly shortly after entering the porous medium. As field experiment a horizontal flow field was established, between two wells with a distance of 5 meters, in a confined, shallow aquifer at a contaminated site in North German lowlands. First a tracer test was performed and a basic model was set up to define the design of the CIC injection experiment. Then CIC suspension was introduced into the aquifer at the injection well while the second well was pumped and samples taken there to observe the breakthrough of CIC. This was based on direct visual inspection and total particle and iron concentrations of water samples analyzed in the laboratory later. It could be concluded that at least 12% of the CIC amount injected reached the extraction well in due course, some of it traveling distances larger than 10 meters in the non-uniform dipole flow field. This demonstrated that these CIC particles have a substantial mobility for reaching larger volumes of a contaminated aquifer and for interacting there by their reactivity with dissolved contaminants in the pore space. Therefore they seem suited well for groundwater remediation by in-situ formation of reactive barriers for chlorinated solvent plumes or even source removal.

Keywords: carbo-iron colloids, chlorinated solvents, in-situ remediation, particle transport, plume treatment

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6442 Readiness of Thai Restaurant in Bangkok in Applying for Certification of Halal Food Services Standard for Tourism

Authors: Pongsiri Kingkan

Abstract:

This research aims to study the Readiness of Thai Restaurant in Bangkok in Applying for Certification of Halal Food Services Standard for Tourism. This research was conduct by using mix methodology; both quantitative and qualitative data were used. 420 questionnaires were used as tools to collected data from the samples, the restaurant employees. The results were divided into two parts, the demographic data and the Readiness of Thai Restaurant in Bangkok in Applying for Certification of Halal Food Services Standard for Tourism. The majority of samples are single female age between 18–30 years old, who earn about 282.40 US dollars a month. The result of Thai restaurant readiness study demonstrated that readiness in foods and restaurant operating processes were scored at the lowest level. Readiness in social responsibility, food contact persons and food materials were rated at the low level. The readiness of utensils and kitchen tools, waste management, environmental management, and the availability of space to implement the establishment of halal food were scored at the average level. Location readiness, foods service safety and the relationship with the local community were rated at high level. But interestingly there is none of them rated at the highest level.

Keywords: availability, Bangkok, halal, Thai restaurant, readiness

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6441 Characteristics of Plasma Synthetic Jet Actuator in Repetitive Working Mode

Authors: Haohua Zong, Marios Kotsonis

Abstract:

Plasma synthetic jet actuator (PSJA) is a new concept of zero net mass flow actuator which utilizes pulsed arc/spark discharge to rapidly pressurize gas in a small cavity under constant-volume conditions. The unique combination of high exit jet velocity (>400 m/s) and high actuation frequency (>5 kHz) provides a promising solution for high-speed high-Reynolds-number flow control. This paper focuses on the performance of PSJA in repetitive working mode which is more relevant to future flow control applications. A two-electrodes PSJA (cavity volume: 424 mm3, orifice diameter: 2 mm) together with a capacitive discharge circuit (discharge energy: 50 mJ-110 mJ) is designed to enable repetitive operation. Time-Resolved Particle Imaging Velocimetry (TR-PIV) system working at 10 kHz is exploited to investigate the influence of discharge frequency on performance of PSJA. In total, seven cases are tested, covering a wide range of discharge frequencies (20 Hz-560 Hz). The pertinent flow features (shock wave, vortex ring and jet) remain the same for single shot mode and repetitive working mode. Shock wave is issued prior to jet eruption. Two distinct vortex rings are formed in one cycle. The first one is produced by the starting jet whereas the second one is related with the shock wave reflection in cavity. A sudden pressure rise is induced at the throat inlet by the reflection of primary shock wave, promoting the shedding of second vortex ring. In one cycle, jet exit velocity first increases sharply, then decreases almost linearly. Afterwards, an alternate occurrence of multiple jet stages and refresh stages is observed. By monitoring the dynamic evolution of exit velocity in one cycle, some integral performance parameters of PSJA can be deduced. As frequency increases, the jet intensity in steady phase decreases monotonically. In the investigated frequency range, jet duration time drops from 250 µs to 210 µs and peak jet velocity decreases from 53 m/s to approximately 39 m/s. The jet impulse and the expelled gas mass (0.69 µN∙s and 0.027 mg at 20 Hz) decline by 48% and 40%, respectively. However, the electro-mechanical efficiency of PSJA defined by the ratio of jet mechanical energy to capacitor energy doesn’t show significant difference (o(0.01%)). Fourier transformation of the temporal exit velocity signal indicates two dominant frequencies. One corresponds to the discharge frequency, while the other accounts for the alternation frequency of jet stage and refresh stage in one cycle. The alternation period (300 µs approximately) is independent of discharge frequency, and possibly determined intrinsically by the actuator geometry. A simple analytical model is established to interpret the alternation of jet stage and refresh stage. Results show that the dynamic response of exit velocity to a small-scale disturbance (jump in cavity pressure) can be treated as a second-order under-damping system. Oscillation frequency of the exit velocity, namely alternation frequency, is positively proportional to exit area, but inversely proportional to cavity volume and throat length. Theoretical value of alternation period (305 µs) agrees well with the experimental value.

Keywords: plasma, synthetic jet, actuator, frequency effect

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6440 The Effect of Media Effect, Conformity, and Personality on Customers’ Purchase Intention under the Influence of COVID-19 Pandemic

Authors: Tsai-Yun Liao, Fang-Yi Hsu

Abstract:

Consumer behavior and consumption patterns have changed in reacting to the threat of COVID-19 pandemic situations. In order to explore the factors affecting customers’ purchase intention under the influence of the COVID-19 pandemic, this research uses structural equation modeling to explore the effect of media effect, conformity, and personality on customers’ purchase intention. Four essential objectives are investigated: how does media affect the conformity and perceived value of customers; the effect of media effect, conformity, and personality on customers’ purchase intention; the moderating effect of personality; and the mediating effect of perceived value toward purchase intention. By convenience sampling method, 428 questionnaires were collected, and the total number of valid samples was 406. Data analysis and results indicate that: (1) The media effect positively affects conformity. (2) The media effect positively affects perceived value. (3) Both conformity and perceived value positively affect purchase intention. (4) Consumer’s personality of openness to experience moderates the relationship between conformity and purchase intention. (5) Media effect affects purchase intention through the mediating effect of perceived value. This study contributes to the research by providing the factors affecting customers’ purchase intention and to the enterprises by maintaining incumbent customers and attracting potential customers.

Keywords: COVID-19, media effect, conformity, personality, purchase intention

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6439 Effect of Manganese Doping Percentage on Optical Band Gap and Conductivity of Copper Sulphide Nano-Films Prepared by Electrodeposition Method

Authors: P. C. Okafor, A. J. Ekpunobi

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Mn doped copper sulphide (CuS:Mn) nano-films were deposited on indiums coated tin oxide (ITO) glass substrates using electrodeposition method. Electrodeposition was carried out using bath of PH = 3 at room temperature. Other depositions parameters such as deposition time (DT) are kept constant while Mn doping was varied from 3% to 23%. Absorption spectra of CuS:Mn films was obtained by using JENWAY 6405 UV-VIS -spectrophotometer. Optical band gap (E_g ), optical conductivity (σo) and electrical conductivity (σe) of CuS:Mn films were determined using absorption spectra and appropriate formula. The effect of Mn doping % on these properties were investigated. Results show that film thickness (t) for the 13.27 nm to 18.49 nm; absorption coefficient (α) from 0.90 x 1011 to 1.50 x 1011 optical band gap from 2.29eV to 2.35 eV; optical conductivity from 1.70 x 1013 and electrical conductivity from 160 millions to 154 millions. Possible applications of such films for solar cells fabrication and optoelectronic devices applications were also discussed.

Keywords: copper sulphide (CuS), Manganese (Mn) doping, electrodeposition, optical band gap, optical conductivity, electrical conductivity

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6438 Application of Artificial Neural Network in Assessing Fill Slope Stability

Authors: An-Jui. Li, Kelvin Lim, Chien-Kuo Chiu, Benson Hsiung

Abstract:

This paper details the utilization of artificial intelligence (AI) in the field of slope stability whereby quick and convenient solutions can be obtained using the developed tool. The AI tool used in this study is the artificial neural network (ANN), while the slope stability analysis methods are the finite element limit analysis methods. The developed tool allows for the prompt prediction of the safety factors of fill slopes and their corresponding probability of failure (depending on the degree of variation of the soil parameters), which can give the practicing engineer a reasonable basis in their decision making. In fact, the successful use of the Extreme Learning Machine (ELM) algorithm shows that slope stability analysis is no longer confined to the conventional methods of modeling, which at times may be tedious and repetitive during the preliminary design stage where the focus is more on cost saving options rather than detailed design. Therefore, similar ANN-based tools can be further developed to assist engineers in this aspect.

Keywords: landslide, limit analysis, artificial neural network, soil properties

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6437 The Kinks, the Solitons, and the Shocks in Series Connected Discrete Josephson Transmission Lines

Authors: Eugene Kogan

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We analytically study the localized running waves in the discrete Josephson transmission lines (JTL), constructed from Josephson junctions (JJ) and capacitors. The quasi-continuum approximation reduces the calculation of the running wave properties to the problem of equilibrium of an elastic rod in the potential field. Making additional approximations, we reduce the problem to the motion of the fictitious Newtonian particle in the potential well. We show that there exist running waves in the form of supersonic kinks and solitons and calculate their velocities and profiles. We show that the nonstationary smooth waves, which are small perturbations on the homogeneous non-zero background, are described by Korteweg-de Vries equation, and those on zero background -by the modified Korteweg-de Vries equation. We also study the effect of dissipation on the running waves in JTL and find that in the presence of the resistors, shunting the JJ and/or in series with the ground capacitors, the only possible stationary running waves are the shock waves, whose profiles are also found.

Keywords: Josephson transmission line, shocks, solitary waves, nonlinear waves

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6436 Opportunity Development and Entrepreneurial Process

Authors: Abosede Mosunmola Odeseye

Abstract:

The sustainability of nations’ economies today have proven to be unrealistic in a constantly changing world without appropriate accordance to entrepreneurship role and its processes. This role has therefore proven to be a product of the available and discoverable opportunities by an individual/organisation in any pattern – innovation, discovery, diffusion, imitation amidst possible challenges. In light of these, this paper examined the relationship between opportunity development and entrepreneurial processes as well as the factors determining individual’s opportunity development and the success of entrepreneurial processes. Systematic review method was adopted for selecting relevant academic materials. The theoretical base of this paper was anchored on Schumpeter’s entrepreneurial innovation model and Drucker and Stevenson’s opportunity-based entrepreneurship theory. Based on the reviewed literature, it was discovered that rough business idea “opportunity” in any form – techniques/product encounter various obstacles to achieve its development, acceptability and sustainability. In essence, the findings revealed that the birth of every opportunity is as a result of the individual/organisation and environmental factors to be able to scale through the whole process successfully. Due to the outcome of this paper, it was recommended that the organisations/government should endeavour to create an enabling environment for a rough business idea to come to life amidst the hurdles of the entrepreneurial process.

Keywords: entrepreneurial process, entrepreneurship, opportunity, opportunity development, organisation, sustainability

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6435 Saving Lives: Alternative Approaches to Reducing Gun Violence

Authors: Angie M. Wolf, DeVone Boggan

Abstract:

This paper highlights an innovative and nontraditional violence prevention program that is making a noticeable impact in what was once one of the country’s most violent communities. With unique and tailored strategies, the Operation Peacemaker Fellowship, established in Richmond, California, combines components of evidence-based practices with a community-oriented focus on relationships and mentoring to fill a gap in services and increase community safety. In an effort to highlight these unique strategies and provide a blueprint for other communities with violent crime problems, the authors of this paper hope to clearly delineate how one community is moving forward with vanguard approaches to invest in the lives of young men who once were labeled the communities’ most violent, even the most deadly, youth. The impact of this program is evidenced through the fellows’ own voices as they illuminate the experience of being in the Fellowship. In interviews, fellows’ describe how participating in this program has transformed their lives, and the lives of those they love. The authors of this article spent more than two years researching this Fellowship program in order to conduct an evaluation of it and, ultimately, to demonstrate how this program is a testament to the power of relationship and love combined with evidence-based practices, consequently enriching the lives of youth and the community that embraces them.

Keywords: gun violence prevention, high risk youth, law, policing justice

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6434 A Statistical Energy Analysis Model of an Automobile for the Prediction of the Internal Sound Pressure Level

Authors: El Korchi Ayoub, Cherif Raef

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Interior noise in vehicles is an essential factor affecting occupant comfort. Over recent decades, much work has been done to develop simulation tools for vehicle NVH. At the medium high-frequency range, the statistical energy analysis method (SEA) shows significant effectiveness in predicting noise and vibration responses of mechanical systems. In this paper, the evaluation of the sound pressure level (SPL) inside an automobile cabin has been performed numerically using the statistical energy analysis (SEA) method. A test car cabin was performed using a monopole source as a sound source. The decay rate method was employed to obtain the damping loss factor (DLF) of each subsystem of the developed SEA model. These parameters were then used to predict the sound pressure level in the interior cabin. The results show satisfactory agreement with the directly measured SPL. The developed SEA vehicle model can be used in early design phases and allows the engineer to identify sources contributing to the total noise and transmission paths.

Keywords: SEA, SPL, DLF, NVH

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6433 The Impacts of Negative Moral Characters on Health: An Article Review

Authors: Mansoor Aslamzai, Delaqa Del, Sayed Azam Sajid

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Introduction: Though moral disorders have a high burden, there is no separate topic regarding this problem in the International Classification of Diseases (ICD). Along with the modification of WHO ICD-11, spirituality can prevent the rapid progress of such derangement as well. Objective: This study evaluated the effects of bad moral characters on health, as well as carried out the role of spirituality in the improvement of immorality. Method: This narrative article review was accomplished in 2020-2021 and the articles were searched through the Web of Science, PubMed, BMC, and Google scholar. Results: Based on the current review, most experimental and observational studies revealed significant negative effects of unwell moral characters on the overall aspects of health and well-being. Nowadays, a lot of studies established the positive role of spirituality in the improvement of health and moral disorder. The studies concluded, facilities must be available within schools, universities, and communities for everyone to learn the knowledge of spirituality and improve their unwell moral character world. Conclusion: Considering the negative relationship between unwell moral characters and well-being, the current study proposes the addition of moral disorder as a separate topic in the WHO International Classification of Diseases. Based on this literature review, spirituality will improve moral disorder and establish excellent moral traits.

Keywords: bad moral characters, effect, health, spirituality and well-being

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6432 Effect of Media on Psycho-Social Interaction among the Children with Their Parents of Urban People in Dhaka

Authors: Nazma Sultana

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Social media has become an important part of our daily life. It has a significance influences on the people who use them in their daily life frequently. The number of people using social network sites has been increasing continuously. For this frequent utilization has started to affect our social life. This study examine whether the use of social network sites affects the psychosocial interaction between children and their parents. At first parents introduce their children to the internet and different type of device in their early childhood. Many parents use device for feeding their children by watching rhyme or cartoon. As a result children are habituate with it. In Bangladesh 70% people are heavy internet users. About 23 percent of them spend more than five hours on the social networking sites a day. Media are increasing pervasive in the lives of children-roughly the average child today spends nearly about 45 hours per week with media, compared with 17 hours with parents and 30 hours in school. According to a social learning theory, children & adolescents learn by observing & imitating what they see on screen particularly when these behaviors are realistic or are rewarded. The influence of the media on the psychosocial development of children is profound. Thus it is important for parents to provide guidance on age-appropriate use of all media, including television, radio, music, video games and the internet.

Keywords: social media, psychosocial, Technology, Parent, Social Relationship, Adolescents, Teenage, Youth

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6431 An Analysis on Fibre-Reinforced Composite Material Usage on Urban Furniture

Authors: Nilgun Becenen

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In this study, the structural properties of composite materials with the plastic matrix, which are used in body parts of urban furniture were investigated. Surfaces of the specimens were observed by scanning electron microscopy (SEM: JSM-5200, JEOL) and Climatic environmental test analyses in laboratory conditions were used to analyze the performance of the composite samples. Climate conditions were determined as follow; 3 hour working under the conditions of -10 ºC heat and 20 % moisture, Heating until 45 ºC for 4 hours, 3 hour work at 45 ºC, 3 hour work under the conditions of 45 ºC heat and 80 % moisture, Cooling at -10 ºC for 4 hours. In this cycle, the atmospheric conditions that urban furniture would be exposed to in the open air were taken into consideration. Particularly, sudden heat changes and humidity effect were investigated. The climate conditions show that performance in Low Temperatures: The endurance isn’t affected, hardness does not change, tensile, bending and impact resistance does not change, the view isn’t affected. It has a high environmental performance.

Keywords: fibre-reinforced material, glass fiber, textile science, polymer composites

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6430 Nexus of Community-Based Tourism Business and Sustainable Livelihood Practices: A Case Study of Amaltari Tharu Village Community, Nepal

Authors: Chet Narayan Acharya, Prachyakorn Chaiyakot, Nuttaya Yuangyai

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This research explores the symbiotic relationship between community based tourism (CBT) businesses and sustainable livelihood practices in the context of Amaltari Tharu Village Community, Nepal. Through a thorough investigation, it analyzes the impact of community-based tourism entrepreneurship on local livelihoods. Using an interpretive case study approach, it assesses how tourism activities affect the sociocultural, economic, and environmental dimensions of the community. The research highlights the sustainable livelihood practices embraced by local communities, guided by the principles of sustainable development. The study employs a triangulation approach to analyze data, aiming to generate insights that contribute to a KICK START discourse on sustainable tourism in the region, shedding light on the connection between community-based tourism entrepreneurship and local livelihood practices. The findings are expected to offer valuable discourse among academic researchers and suggestions for sustainable tourism management strategies in similar global contexts.

Keywords: community based tourism businesses, sustainable livelihood, Nepal, sociocultural and environmental impact, kick start discourse

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6429 Campus Living Environments that Contribute to Mental Health: A Path Analysis Based on Environmental Characteristics

Authors: Jing Ren, Guifeng Han

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The mental health of most college students in China is negative due to the multiple pressures of academics, life, and employment. The problem of psychological stress has been widely discussed and needs to be resolved immediately. Therefore, six typical green spaces in Chongqing University, China, were selected to explore the relationship between eight environmental characteristics and students' stress relief. A path analysis model is established using Amos26.0 to explain the paths for environmental characteristics influencing psychological stress relief. The results show that (1) tree species diversity (TSD) has a positive effect on stress relief, thus green coverage ratio (GCR), the proportion of water area (WAP), visual green index (VGI), and color richness (CR) have both positive and negative effects; (2) CR could reduce stress directly and indirectly, while GCR, TSD, WAP, and VGI could only reduce stress indirectly, and the most effective path is TSD→extent→stress relief; (3) CR can reduce stress more greatly for males than females, CR and VGI have better effects for art students than science students. The study can provide a theoretical reference for planning and designing campus living environments to improve students' mental health.

Keywords: public health, residential environment, space planning and management, mental health, path analysis

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6428 The Impact of Motivation on English Language Learning: A Study of HSC Students of Jatir Janak Bangabandhu Sheikh Mujibur Rahman Government College, Dhaka, Bangladesh

Authors: Farina Yasmin

Abstract:

Motivation is an important issue in an EFL setting where very little exposure to English in everyday life is clearly evident. In Bangladesh, English is taught as a foreign language. Language teachers cannot effectively teach a language if they do not understand the relationship between motivation and its effect on foreign language learning. The main purpose of this research is to explore the fact why HSC students are less motivated towards English language learning, what factors are affecting motivation, how to motivate them and the role of motivation in their success. The research questions were (a) what are the reasons of lack of motivation? and (b) what are the impacts of motivation on English language learning? The study was both qualitative and quantitative in nature. The data was collected via pretest - posttest, interviews, and a questionnaire on the five point Likert scale. Triangulation of the data was made for the validity of the research. The population of this research consisted of 50 HSC level students from Jatir Janak Bangabandhu Sheikh Mujibur Rahman Government College, Dhaka, Bangladesh. The data was analyzed with means, comparison and t-test. The results showed that there is a strong relation between motivation and success in foreign language learning. Finally, some pedagogical implications and suggestions were presented to arouse the students’ motivation to learn English.

Keywords: EFL, HSC, motivation, success

Procedia PDF Downloads 360
6427 Zinc (II) Complexes of Nitrogen, Oxygen and Sulfur Coordination Modes: Synthesis, Spectral Studies and Antibacterial Activities

Authors: Ayodele Odularu, Peter Ajibade, Albert Bolhuis

Abstract:

This study aimed at assessing the antibacterial activities of four zinc (II) complexes. Zinc (II) complexes of nitrogen, oxygen and sulfur coordination modes were synthesized using direct substitution reaction. The characterization techniques involved physicochemical properties (molar conductivity) and spectroscopic techniques. The molar conductivity gave the non-electrolytic nature of zinc (II) complexes. The spectral studies of zinc (II) complexes were done using electronic spectra (UV-Vis) and Fourier Transform Infra-red Spectroscopy (FT-IR). Spectral data from the spectroscopic studies confirmed the coordination of the mixed ligands with zinc (II) ion. The antibacterial activities of zinc(II) complexes of were all in supportive of Overtone’s concept and Tweedy’s theory of chelation for bacterial strains of S. aureus MRSA252 and E coli MC4100 because the zones of inhibition were greater than the corresponding ligands. In summary, all zinc (II) complexes of ZEPY, ZE1PH, ZE1PY and ZE135PY all have potentials for antibacterial activities.

Keywords: antibacterial activities, spectral studies, syntheses, zinc(II) complexes

Procedia PDF Downloads 262
6426 Effects of Soil Erosion on Vegetation Development

Authors: Josephine Wanja Nyatia

Abstract:

The relationship between vegetation and soil erosion deserves attention due to its scientific importance and practical applications. A great deal of information is available about the mechanisms and benefits of vegetation in the control of soil erosion, but the effects of soil erosion on vegetation development and succession is poorly documented. Research shows that soil erosion is the most important driving force for the degradation of upland and mountain ecosystems. Soil erosion interferes with the process of plant community development and vegetation succession, commencing with seed formation and impacting throughout the whole growth phase and affecting seed availability, dispersal, germination and establishment, plant community structure and spatial distribution. There have been almost no studies on the effects of soil erosion on seed development and availability, of surface flows on seed movement and redistribution, and their influences on soil seed bank and on vegetation establishment and distribution. However, these effects may be the main cause of low vegetation cover in regions of high soil erosion activity, and these issues need to be investigated. Moreover, soil erosion is not only a negative influence on vegetation succession and restoration but also a driving force of plant adaptation and evolution. Consequently, we need to study the effects of soil erosion on ecological processes and on development and regulation of vegetation succession from the points of view of pedology and vegetation, plant and seed ecology, and to establish an integrated theory and technology for deriving practical solutions to soil erosion problems

Keywords: soil erosion, vegetation, development, seed availability

Procedia PDF Downloads 59
6425 Variogram Fitting Based on the Wilcoxon Norm

Authors: Hazem Al-Mofleh, John Daniels, Joseph McKean

Abstract:

Within geostatistics research, effective estimation of the variogram points has been examined, particularly in developing robust alternatives. The parametric fit of these variogram points which eventually defines the kriging weights, however, has not received the same attention from a robust perspective. This paper proposes the use of the non-linear Wilcoxon norm over weighted non-linear least squares as a robust variogram fitting alternative. First, we introduce the concept of variogram estimation and fitting. Then, as an alternative to non-linear weighted least squares, we discuss the non-linear Wilcoxon estimator. Next, the robustness properties of the non-linear Wilcoxon are demonstrated using a contaminated spatial data set. Finally, under simulated conditions, increasing levels of contaminated spatial processes have their variograms points estimated and fit. In the fitting of these variogram points, both non-linear Weighted Least Squares and non-linear Wilcoxon fits are examined for efficiency. At all levels of contamination (including 0%), using a robust estimation and robust fitting procedure, the non-weighted Wilcoxon outperforms weighted Least Squares.

Keywords: non-linear wilcoxon, robust estimation, variogram estimation, wilcoxon norm

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6424 Identification of High Stress Regions in Proximal Femur During Single-Leg Stance and Sideways Fall Using QCT-Based Finite Element Model

Authors: Hossein Kheirollahi, Yunhua Luo

Abstract:

Studying stress and strain trends in the femur and recognizing femur failure mechanism is very important for preventing hip fracture in the elderly. The aim of this study was to identify high stress and strain regions in the femur during normal walking and falling to find the mechanical behavior and failure mechanism of the femur. We developed a finite element model of the femur from the subject’s quantitative computed tomography (QCT) image and used it to identify potentially high stress and strain regions during the single-leg stance and the sideways fall. It was found that fracture may initiate from the superior region of femoral neck and propagate to the inferior region during a high impact force such as sideways fall. The results of this study showed that the femur bone is more sensitive to strain than stress which indicates the effect of strain, in addition to effect of stress, should be considered for failure analysis.

Keywords: finite element analysis, hip fracture, strain, stress

Procedia PDF Downloads 493
6423 The High Temperature Damage of DV–2 Turbine Blade Made from Ni–Base Superalloy

Authors: Juraj Belan, Lenka Hurtalová, Eva Tillová, Alan Vaško, Milan Uhríčik

Abstract:

High-pressure turbine (HPT) blades of DV–2 jet engines are made from Ni–base superalloy, a former Soviet Union production, specified as ŽS6K. For improving its high-temperature resistance are blades covered with Al–Si diffusion layer. A regular operation temperature of HPT blades vary from 705°C to 750°C depending on jet engine regime. An over-crossing working temperature range causes degradation of protective alitize layer as well as base material–gamma matrix and gamma prime particles what decreases turbine blade lifetime. High-temperature degradation has mainly diffusion mechanism and causes coarsening of strengthening phase gamma prime and protective alitize layer thickness growing. All changes have a significant influence on high-temperature properties of base material.

Keywords: alitize layer, gamma prime phase, high-temperature degradation, Ni–base superalloy ŽS6K, turbine blade

Procedia PDF Downloads 517
6422 Wicking and Evaporation of Liquids in Knitted Fabrics: Analytic Solution of Capillary Rise Restrained by Gravity and Evaporation

Authors: N. S. Achour, M. Hamdaoui, S. Ben Nasrallah

Abstract:

Wicking and evaporation of water in porous knitted fabrics is investigated by combining experimental and analytical approaches: The standard wicking model from Lucas and Washburn is enhanced to account for evaporation and gravity effects. The goal is to model the effect of gravity and evaporation on wicking using simple analytical expressions and investigate the influence of fabrics geometrical parameters, such as porosity and thickness on evaporation impact on maximum reachable height values. The results show that fabric properties have a significant influence on evaporation effect. In this paper, an experimental study of determining water kinetics from different knitted fabrics were gravimetrically investigated permitting the measure of the mass and the height of liquid rising in fabrics in various atmospheric conditions. From these measurements, characteristic pore parameters (capillary radius and permeability) can be determined.

Keywords: evaporation, experimental study, geometrical parameters, model, porous knitted fabrics, wicking

Procedia PDF Downloads 570
6421 Hybrid Finite Element Analysis of Expansion Joints for Piping Systems in Aircraft Engine External Configurations and Nuclear Power Plants

Authors: Dong Wook Lee

Abstract:

This paper presents a method to analyze the stiffness of the expansion joint with structural support using a hybrid method combining computational and analytical methods. Many expansion joints found in tubes and ducts of mechanical structures are designed to absorb thermal expansion mismatch between their structural members and deal with misalignments introduced from the assembly/manufacturing processes. One of the important design perspectives is the system’s vibrational characteristics. We calculate the stiffness as a characterization parameter for structural joint systems using a combined Finite Element Analysis (FEA) and an analytical method. We apply the methods to two sample applications: external configurations of aircraft engines and nuclear power plant structures.

Keywords: expansion joint, expansion joint stiffness, finite element analysis, nuclear power plants, aircraft engine external configurations

Procedia PDF Downloads 98