Abstract: The current study investigated the effect of catalyst ratio and methanol to oil ratio on biodiesel production by using central composite design. Biodiesel was produced by transesterification using sodium hydroxide as a homogeneous catalyst, a laboratory scale reactor consisting of flat bottom flask mounts with a reflux condenser and a heating plate was used to produce biodiesel. Key parameters, including, time, temperature and mixing rate were kept constant at 60 minutes, 60 oC and 600 RPM, respectively. From the results obtained, it was observed that the biodiesel yield depends on catalyst ratio and methanol to oil ratio. The highest yield of 50.65% was obtained at catalyst ratio of 0.5 wt.% and methanol to oil mole ratio 10.5. The analysis of variances of biodiesel yield showed the R Squared value of 0.8387. A quadratic mathematical model was developed to predict the biodiesel yield in the specified parameters ranges.
Abstract: The rapidly increasing number of population in the limited area creates an effect on the idea of the improvement of the area to suit the environment and the needs of people. Faculty of architecture Chiang Mai University is also expanding in both variety fields of study and quality of education. In 2020, the new department will be introduced in the faculty which is Department of Landscape Architecture. With the limitation of the area in the existing building, the faculty plan to renovate some parts of its school for anticipates the number of students who will join the program in the next two years. As a result, the old wooden workshop area is selected to be renovated as student studio space. With such condition, it is necessary to study the restriction and the distinctive environment of the site prior to the improvement in order to find ways to manage the existing space due to the fact that the primary functions that have been practiced in the site, an old wooden workshop space and the new function, studio space, are too different. 72.9% of the annual times in the room are considered to be out of the thermal comfort condition with high relative humidity. This causes non-comfort condition for occupants which could promote mould growth. This study aims to analyze thermal comfort condition in the Landscape Learning Studio Area for finding the solution to improve indoor air quality and respond to local conditions. The research methodology will be in two parts: 1) field gathering data on the case study 2) analysis and finding the solution of improving indoor air quality. The result of the survey indicated that the room needs to solve non-comfort condition problem. This can be divided into two ways which are raising ventilation and indoor temperature, e.g. improving building design and stack driven ventilation, using fan for enhancing more internal ventilation.
Abstract: Diagnosis of breast cancer at early stages has seen better clinical and survival outcomes. Survival rates in developing countries like India are very low due to accessibility and affordability issues of screening tests such as Mammography. In addition, Mammography is not much effective in younger women with dense breasts. This leaves a gap in current screening methods. Thermalytix is a new technique for detecting breast abnormality in a non-contact, non-invasive way. It is an AI-enabled computer-aided diagnosis solution that automates interpretation of high resolution thermal images and identifies potential malignant lesions. The solution is low cost, easy to use, portable and is effective in all age groups. This paper presents the results of a retrospective comparative analysis of Thermalytix over Mammography and Clinical Breast Examination for breast cancer screening. Thermalytix was found to have better sensitivity than both the tests, with good specificity as well. In addition, Thermalytix identified all malignant patients without palpable lumps.
Abstract: From the last decades, there is a significant technological advancement in the field of robotics, and a number of modular self-reconfigurable robots were introduced that can help in space exploration, bucket to stuff, search, and rescue operation during earthquake, etc. As there are numbers of self-reconfigurable robots, choosing the optimum one is always a concern for robot user since there is an increase in available features, facilities, complexity, etc. The objective of this research work is to present a multiple attribute decision making based methodology for coding, evaluation, comparison ranking and selection of modular self-reconfigurable robots using a technique for order preferences by similarity to ideal solution approach. However, 86 attributes that affect the structure and performance are identified. A database for modular self-reconfigurable robot on the basis of different pertinent attribute is generated. This database is very useful for the user, for selecting a robot that suits their operational needs. Two visual methods namely linear graph and spider chart are proposed for ranking of modular self-reconfigurable robots. Using five robots (Atron, Smores, Polybot, M-Tran 3, Superbot), an example is illustrated, and raking of the robots is successfully done, which shows that Smores is the best robot for the operational need illustrated, and this methodology is found to be very effective and simple to use.
Abstract: Data hiding can be achieved by Steganography or invisible digital watermarking. For digital watermarking, both accurate retrieval of the embedded watermark and the integrity of the cover image are important. Medical image security in Teleradiology is one of the applications where the embedded patient record needs to be extracted with accuracy as well as the medical image integrity verified. In this research paper, the Constant Correlation Spread Spectrum digital watermarking for medical image tamper detection and accurate embedded watermark retrieval is introduced. In the proposed method, a watermark bit from a patient record is spread in a medical image sub-block such that the correlation of all watermarked sub-blocks with a spreading code, W, would have a constant value, p. The constant correlation p, spreading code, W and the size of the sub-blocks constitute the secret key. Tamper detection is achieved by flagging any sub-block whose correlation value deviates by more than a small value, ℇ, from p. The major features of our new scheme include: (1) Improving watermark detection accuracy for high-pixel depth medical images by reducing the Bit Error Rate (BER) to Zero and (2) block-level tamper detection in a single computational process with simultaneous watermark detection, thereby increasing utility with the same computational cost.
Abstract: Introduction: Currently, there has been an increasing concern about the provision of palliative care in non-oncological patients in both professional literature and clinical practice. However, there is not much scientific information on how to provide neurological and palliative care together. The main objective of the project is to create and to verify a concept of neuro-palliative and rehabilitative care for patients with selected neurological diseases in an advanced stage of the disease and also to evaluate bio-psychosocial and spiritual needs of these patients and their caregivers related to the quality of life using created standardized tools. Methodology: Triangulation of research methods (qualitative and quantitative) will be used. A concept of care and assessment tools will be developed by analyzing interviews and focus groups. Qualitative data will be analyzed using grounded theory. The concept of care will be tested in the context of the intervention study. Using quantitative analysis, we will assess the effect of an intervention provided on the saturation of needs, quality of life, and quality of care. A research sample will be made up of the patients with selected neurological diseases (Parkinson´s syndrome, motor neuron disease, multiple sclerosis, Huntington’s disease), together with patients´ family members. Based on the results, educational materials and a certified course for health care professionals will be created. Findings: Based on qualitative data analysis, we will propose the concept of integrated care model combining neurological, rehabilitative and specialist palliative care for patients with selected neurological diseases in different settings of care and services. Patients´ needs related to quality of life will be described by newly created and validated measuring tools before the start of intervention (application of neuro-palliative and palliative approach) and then in the time interval. Conclusion: Based on the results, educational materials and a certified course for doctors and health care professionals will be created.
Abstract: The expanding informal sector in developing countries and in Ghana in particular from the 1980s has now been aggravated by the growing population and downsizing in both the public and private sectors, with displaced workers finding alternative livelihoods in the informal sector. Youth and graduate unemployment also swell the numbers and further promote the continuity of the sector. Formal workers and institutions facilitate the growth and complicate demarcations between informality within the formal and informal sectors. In spite of its growth and increasing importance, the informal economy does not feature in policy debates and has often been neglected by the Ghana government. The phenomenon has evolved with modernity into myriad unimaginable forms. Indeed, actors within the sector often clash with the interventions provided by policy makers - because neither the operatives nor the activities they perform can be clearly defined. This study uses in-depth interviews to explore the behavioural nature of the informal workers in Ghana to understand how the operatives describe and perceive the sector, and to identify the factors that influence their drive to stay within the sector. This paper concludes that the operatives clearly distinguish between the formal and informal sectors and identify the characteristics and conditions that constitute the informal sector. Other workers are trapped between formality and informality. The findings also enumerate the push and pull factors contributing to the growth of the sector.
Abstract: The performance of hybrid amplify and forward -
decode and forward (AF-DF) hybrid radio frequency/free space
optical (RF/FSO) communication system, that adopts M-ary pulse
position modulation (MPPM) techniques, is analyzed. Both exact
and approximate symbol-error rates (SERs) are derived. The random
variations of the received optical irradiance, produced by the
atmospheric turbulence, is modeled by the gamma-gamma (GG)
statistical distribution. A closed-form expression for the probability
density function (PDF) is derived for the whole above system
is obtained. Thanks to the use of hybrid AF-DF hybrid RF/FSO
configuration and MPPM, the effects of atmospheric turbulence is
mitigated; hence the capacity of combating atmospheric turbulence
and the transmissitted signal quality are improved.
Abstract: This paper presents an experimental investigation for the characteristics of an energy harvesting device exploiting flow-induced vibration in a wind tunnel. A stationary bluff body is connected with a downstream tip body via an aluminium cantilever beam. Various lengths of aluminium cantilever beam and different shapes of downstream tip body are considered. The results show that the characteristics of the energy harvester’s vibration depend on both the length of the aluminium cantilever beam and the shape of the downstream tip body. The highest ratio between vibration amplitude and bluff body diameter was found to be 1.39 for an energy harvester with a symmetrical triangular tip body and L/D1 = 5 at 9.8 m/s of flow speed (Re = 20077). Using this configuration, the electrical energy was extracted with a polyvinylidene fluoride (PVDF) piezoelectric beam with different load resistances, of which the optimal value could be found on each Reynolds number. The highest power output was found to be 3.19 µW, at 9.8 m/s of flow speed (Re = 20077) and 27 MΩ of load resistance.
Abstract: Health information technologies promise higher quality, safer care and much more for both patients and professionals. Despite their promise, they are costly to develop and difficult to implement. On the other hand, user acceptance and usage determine the success of implemented information technology in healthcare. This study provides a model to understand health professionals’ perception and expectation of health information technology. Extensive literature review has been conducted to determine the main factors to be measured. A questionnaire has been designed as a measurement model and submitted to the personnel of an in vitro fertilization clinic. The respondents’ degree of agreement according to five-point Likert scale was 72% for convenient access to data and 69.4% for the importance of data security. There was a significant difference in acceptance of electronic data storage for female respondents. Also, other significant differences between professions were obtained.
Abstract: Eating a meal is among the Activities of Daily Living,
but it takes a lot of time and effort for people with physical
or functional limitations. Dedicated technologies are cumbersome
and not portable, while general-purpose assistive robots such as
wheelchair-based manipulators are too hard to control for elaborate
continuous motion like eating. Eating with such devices has not
previously been automated, since there existed no description of
a feeding motion for uncontrolled environments. In this paper, we
introduce a feeding mode for assistive manipulators, including a
mathematical description of trajectories for motions that are difficult
to perform manually such as gathering and scooping food at a
defined/desired pace. We implement these trajectories in a sequence
of movements for a semi-automated feeding mode which can be
controlled with a very simple 3-button interface, allowing the user
to have control over the feeding pace. Finally, we demonstrate the
feeding mode with a JACO robotic arm and compare the eating
speed, measured in bites per minute of three eating methods: a
healthy person eating unaided, a person with upper limb limitations
or disability using JACO with manual control, and a person with
limitations using JACO with the feeding mode. We found that the
feeding mode allows eating about 5 bites per minute, which should
be sufficient to eat a meal under 30min.
Abstract: In impedance spectroscopy (IS) the response of a photo-active device is analysed as a function of ac bias. It is widely applied in a broad class of material systems and devices. It gives access to fundamental mechanisms of operation of solar cells. We have implemented a method of IS where we modulate the light instead of the bias. This scheme allows us to analyze not only carrier dynamics but also impedance of device locally. Here, using this scheme, we have measured the frequency-dependent photocurrent response of the thin-film planar and nano-textured Si solar cells using this method. Photocurrent response is measured in range of 50 Hz to 50 kHz. Bode and Nyquist plots are used to determine characteristic lifetime of both the cells. Interestingly, the carrier lifetime of both planar and nano-textured solar cells depend on back and front contact positions. This is due to either heterogeneity of device or contacts are not optimized. The estimated average lifetime is found to be shorter for the nano-textured cell, which could be due to the influence of the textured interface on the carrier relaxation dynamics.
Abstract: A numerical investigation of unsteady mixed convection heat transfer in a 3D moving top wall enclosure, which has a central rotating cylinder and uses either artificial roughness on the bottom hot plate or smooth bottom hot plate to study the heat transfer enhancement, is completed for fixed circular cylinder, and anticlockwise and clockwise rotational speeds, -1 ≤ Ω ≤ 1, at Reynolds number of 5000. The top lid-driven wall was cooled, while the other remaining walls that completed obstructed cubic were kept insulated and motionless. A standard k-ε model of Unsteady Reynolds-Averaged Navier-Stokes (URANS) method is involved to deal with turbulent flow. It has been clearly noted that artificial roughness can strongly control the thermal fields and fluid flow patterns. Ultimately, the heat transfer rate has been dramatically increased by involving artificial roughness on the heated bottom wall in the presence of rotating cylinder.
Abstract: Smart grid is a term used to describe the next generation
power grid. New challenges such as integration of renewable and
decentralized energy sources, the requirement for continuous grid
estimation and optimization, as well as the use of two-way flows
of energy have been brought to the power gird. In order to achieve
efficient, reliable, sustainable, as well as secure delivery of electric
power more and more information and communication technologies
are used for the monitoring and the control of power grids.
Consequently, the need for cybersecurity is dramatically increased
and has converged into several standards which will be presented
here. These standards for the smart grid must be designed to
satisfy both performance and reliability requirements. An in depth
investigation of the effect of retrospectively embedded security in
existing grids on it’s dynamic behavior is required. Therefore, a
retrofitting plan for existing meters is offered, and it’s performance
in a test low voltage microgrid is investigated. As a result of this,
integration of security measures into measurement architectures of
smart grids at the design phase is strongly recommended.
Abstract: The use of nanostructured semiconducting material to catalyze degradation of environmental pollutants still receives much attention to date. One of the desired characteristics for pollutant degradation under ultra-violet visible light is the materials with extended carrier charge separation that allows for electronic transfer between the catalyst and the pollutants. In this work, zinc oxide n-type semiconductor vertically aligned structures were fabricated on silicon (100) substrates using the chemical bath deposition method. The as-synthesized structures were treated with nickel and sulphur. X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy were used to characterize the phase purity, structural dimensions and elemental composition of the obtained structures respectively. Photoluminescence emission measurements showed a decrease in both the near band edge emission as well as the defect band emission upon addition of nickel and sulphur with different concentrations. This was attributed to increased charger-carrier-separation due to the presence of Ni-S material on ZnO surface, which is linked to improved charge transfer during photocatalytic reactions.
Abstract: The majority of today’s mobile robots are very dependent on battery power. Mobile robots can operate untethered for a number of hours but eventually they will need to recharge their batteries in-order to continue to function. While computer processing and sensors have become cheaper and more powerful each year, battery development has progress very little. They are slow to re-charge, inefficient and lagging behind in the general progression of robotic development we see today. However, batteries are relatively cheap and when fully charged, can supply high power output necessary for operating heavy mobile robots. As there are no cheap alternatives to batteries, we need to find efficient ways to manage the power that batteries provide during their operational lifetime. This paper proposes the use of autonomic principles of self-adaption to address the behavioral changes a battery experiences as it gets older. In life, as we get older, we cannot perform tasks in the same way as we did in our youth; these tasks generally take longer to perform and require more of our energy to complete. Batteries also suffer from a form of degradation. As a battery gets older, it loses the ability to retain the same charge capacity it would have when brand new. This paper investigates how we can adapt the current state of a battery charge and cycle count, to the requirements of a mobile robot to perform its tasks.
Abstract: In this paper, a method of fast 3D topography modeling using the high-resolution camera images is studied based on the characteristics of Unmanned Aerial Vehicle (UAV) system for low altitude aerial photogrammetry and the need of three dimensional (3D) urban landscape modeling. Firstly, the existing high-resolution digital camera with special design of overlap images is designed by reconstructing and analyzing the auto-flying paths of UAVs, which improves the self-calibration function to achieve the high precision imaging by software, and further increased the resolution of the imaging system. Secondly, several-angle images including vertical images and oblique images gotten by the UAV system are used for the detail measure of urban land surfaces and the texture extraction. Finally, the aerial photography and 3D topography construction are both developed in campus of Chang-Jung University and in Guerin district area in Tainan, Taiwan, provide authentication model for construction of 3D topography based on combined UAV-based camera images from system. The results demonstrated that the UAV system for low altitude aerial photogrammetry can be used in the construction of 3D topography production, and the technology solution in this paper offers a new, fast, and technical plan for the 3D expression of the city landscape, fine modeling and visualization.
Abstract: As part of a ‘Morphing-Wing’ idea, this study consists
of measuring how a winglet, which is able to change its shape during
the flight, is efficient. Conventionally, winglets are fixed-vertical
platforms at the wingtips, optimized for a cruise condition that the
airplane should use most of the time. However, during a cruise, an
airplane flies through a lot of cruise conditions corresponding to
altitudes variations from 30,000 to 45,000 ft. The fixed winglets are
not optimized for these variations, and consequently, they are
supposed to generate some drag, and thus to deteriorate aircraft fuel
consumption. This research assumes that it exists a winglet position
that reduces the fuel consumption for each cruise condition. In this
way, the methodology aims to find these optimal winglet positions,
and to further simulate, and thus estimate the fuel consumption of an
aircraft wearing this type of adaptive winglet during several cruise
conditions. The adaptive winglet is assumed to have degrees of
freedom given by the various changes of following surfaces: the tip
chord, the sweep and the dihedral angles. Finally, results obtained
during cruise simulations are presented in this paper. These results
show that an adaptive winglet can reduce, thus improve up to 2.12%
the fuel consumption of an aircraft during a cruise.
Abstract: The purpose of the present research is to equate two
test forms as part of a study to evaluate the educational effectiveness
of the ARTé: Mecenas art history learning game. The researcher
applied Item Response Theory (IRT) procedures to calculate item,
test, and mean-sigma equating parameters. With the sample size
n=134, test parameters indicated “good” model fit but low Test
Information Functions and more acute than expected equating
parameters. Therefore, the researcher applied equipercentile equating
and linear equating to raw scores and compared the equated form
parameters and effect sizes from each method. Item scaling in IRT
enables the researcher to select a subset of well-discriminating items.
The mean-sigma step produces a mean-slope adjustment from the
anchor items, which was used to scale the score on the new form
(Form R) to the reference form (Form Q) scale. In equipercentile
equating, scores are adjusted to align the proportion of scores in each
quintile segment. Linear equating produces a mean-slope adjustment,
which was applied to all core items on the new form. The study
followed a quasi-experimental design with purposeful sampling of
students enrolled in a college level art history course (n=134) and
counterbalancing design to distribute both forms on the pre- and posttests.
The Experimental Group (n=82) was asked to play ARTé:
Mecenas online and complete Level 4 of the game within a two-week
period; 37 participants completed Level 4. Over the same period, the
Control Group (n=52) did not play the game. The researcher
examined between group differences from post-test scores on test
Form Q and Form R by full-factorial Two-Way ANOVA. The raw
score analysis indicated a 1.29% direct effect of form, which was
statistically non-significant but may be practically significant. The
researcher repeated the between group differences analysis with all
three equating methods. For the IRT mean-sigma adjusted scores,
form had a direct effect of 8.39%. Mean-sigma equating with a small
sample may have resulted in inaccurate equating parameters.
Equipercentile equating aligned test means and standard deviations,
but resultant skewness and kurtosis worsened compared to raw score
parameters. Form had a 3.18% direct effect. Linear equating
produced the lowest Form effect, approaching 0%. Using linearly
equated scores, the researcher conducted an ANCOVA to examine
the effect size in terms of prior knowledge. The between group effect
size for the Control Group versus Experimental Group participants
who completed the game was 14.39% with a 4.77% effect size
attributed to pre-test score. Playing and completing the game
increased art history knowledge, and individuals with low prior
knowledge tended to gain more from pre- to post test. Ultimately,
researchers should approach test equating based on their theoretical
stance on Classical Test Theory and IRT and the respective assumptions. Regardless of the approach or method, test equating
requires a representative sample of sufficient size. With small sample
sizes, the application of a range of equating approaches can expose
item and test features for review, inform interpretation, and identify
paths for improving instruments for future study.
Abstract: In this paper, the velocity potential and stream
function of capture zone for a well field in an aquifer bounded by two
parallel streams with or without a uniform regional flow of any
directions are presented. The well field includes any number of
extraction or injection wells or a combination of both types with any
pumping rates. To delineate the capture envelope, the potential and
streamlines equations are derived by conformal mapping method.
This method can help us to release constrains of other methods. The
equations can be applied as useful tools to design in-situ groundwater
remediation systems, to evaluate the surface–subsurface water
interaction and to manage the water resources.