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Hybrid Genetic Algorithm and Kalman Filter Approach to Estimate the Clamping Force of Electro-Mechanical Brake
Get PDFIn thispaper, a hybrid genetic algorithm (GA) and Kalman filter approach to combining motor encoder and current sensor models is presented to accurate estimate the clamping force of an electro-mechanical brake (EMB). Elimination of the clamping force sensor and measurement cables results in lower cost and increased reliability of an EMB system, including its electric motor.A Kalman filter is a special kind of observer that provides optimal filtering of the measurement noise and inside the system if the covariances of these noises are known. The proposed combined estimator is based on Kalman filter optimized by GA in which the motor encoder is used in a dynamic stiffness model and the motor current sensor is used to give measurement updates in a torque balance model. A real-coded GA is used to optimize the noise matrices and improve the performance of the Kalman filter. Experimental results show that, by using the proposed estimator, the virtual clamping force sensor can handle highly dynamic situations, making it suitable for possible use in sensorless fault-tolerant control. It is shown that the proposed combined estimator improves the root mean square error (RMSE) performance. The developed estimator can be used in real vehicle environments because it can adapt to parameter variations
Development of IoT-Based Sensor Tag for Smart Factory
Get PDFTo reduce the rate of defective products and ensure the health of employees, it has become increasingly necessary to improve air quality in factories. To do so, it is important to accurately determine the air quality in the factory first. However, currently available industry-grade sensors require complex and often separate construction processes, making them difficult to use in complicated industrial sites. In order to solve such an issue, this study developed an IoT-based sensor that can collect data such as factory temperature, humidity, CO2 levels, dust, and stench. This study has also developed software to manage the IoT-based sensors, which can transmit the data via RF communication. Sensor tags were tested for basic environmental durability, including waterproof, dustproof, and vibration standards. The sensors can be connected via USB to a computer to configure its settings and access the stored data within the sensors. Unlike other existing environmental sensors, these can be easily installed anywhere as they transmit data via wireless communication. These sensors can also be installed in the factory to check the factory’s internal pollution level in real time. The application of this sensor will enable the real-time monitoring of air pollution in factories. By locating the polluted areas accurately, it will be possible to exercise distributed control over ventilation devices to prevent further spread of pollutants, while also pushing out the polluted air to maintain an optimal working environment. Future studies should develop a simulation model for determining the ideal installation location for the sensors. There also needs to be further studies in developing a distributed-controlled air-conditioning system to run empirical tests
Deployment of Open Data Kit for Information Management for Various Engineering Projects In Rural, Indonesia
Get PDFAbstract—Open data kit was used in an Engineering context as a data collection, storage and management tool for diverse data types from irrigation channels, weirs, saturated rice paddies and ephemeral stream catchments in the Eastern Indonesian province of Nusa Tenggara Timur. In the islands of West Timor and Flores, information was primarily used to report maintenance issues in the weir, primary, secondary, tertiary and quaternary channels. In Sumba, data was recorded for flow velocity and elevation in saturated zones and sedimentation in an ephemeral stream. Information regarding physical characteristics from groundwater wells was also collected to assess drinking water quality. Smart phone data input forms were developed progressively using Open data kit Build, according to the specific needs of each research project. It was found to be a very user-friendly and effective tool to use in the Engineering context. The features of Open data kit Build allowed us to modify the various forms in remote locations. Developing multiple choice input focused forms made data collection easier for farmers and local government workers. It virtually eliminated the need for hardcopy data, and allowed for versatility with respect to the nature of the multidisciplinary research
A Survey of Collaborative Filtering Recommender Algorithms and Their Evaluation Metrics
Get PDFAbstract—Recommender systems are often used to provide useful recommendations for users. They use previous history of the users-items interactions, e.g. purchase history and/or users rating on items, to provide a suitable recommendation list for any target user. They may also use contextual information available about items and users. Collaborative filtering algorithm and its variants are the most successful recommendation algorithms that have been applied to many applications. Collaborative filtering method works by first finding the most similar users (or items) for a target user (or items), and then building the recommendation lists. There is no unique evaluation metric to assess the performance of recommendations systems, and one often choose the one most appropriate for the application in hand. This paper compares the performance of a number of well-known collaborative filtering algorithms on movie recommendation. To this end, a number of performance criteria are used to test the algorithms. The algorithms are ranked for each evaluation metric and a rank aggregation method is used to determine the wining algorithm. Our experiments show that the probabilistic matrix factorization has the top performance in this dataset, followed by item-based and user-based collaborative filtering. Non-negative matrix factorization and Slope 1 has the worst performance among the considered algorithms.
Keywords—Social networks analysis and mining, big data, recommender systems, collaborative filtering
Formulation of Lipbutter Using Red Dragon Fruit's Extract (HylocereusCostaricensis)As Natural Dyes With Various Oil Phase Concentration
Get PDFLipbutter is a cosmetic preparation used for people with dry and cracked lips problems. One example of a fruit that can be used as a natural dye is a red dragon fruit (Hylocereuscostaricensis) because it contains anthocyanin pigment that serves as a color pigment. Red dragon fruit is a fruit that has several properties such as antioxidants, antimicrobials, boost the immune system and contains some good vitamins for the skin such as vitamin E, vitamin C and vitamin B three. Red dragon fruit can be used as a lip moisturizer and can overcome dry skin that will effective when used regularly. The aim of this research is to make lipbutter preparation using red dragon fruit extract as natural dye, with oil phase concentration (Oleumricini). Red Dragon Fruit extracted using a method of escaping with the extract. Made with three formulas. Lipbutter preparation is evaluated pH, melting point, and organoleptys. The results showed that the lipbutter preparations were made to have good texture and aroma but the color was not stable.It can be concluded with the addition of the concentration of castor oil (Oleumricini) to the preparation to yield the highest average pH preparation. With the right melting point also produces a pH corresponding to the physiological pH of the lips
Assessment of Surfactant Flooding With Variations of Slug Injection Strategies in Waterflooded Reservoir
Get PDFInjection of surfactant into waterflooded reservoir which has considerably high water saturation may cause a reduction in surfactant efficiency by means of surfactant dilution and adsorption. Therefore, to maintain expected lowest interfacial tension (IFT) condition, large amount of surfactant, which leads to higher cost, is inevitable. Several studies have observed that reduction in surfactant concentration slug at the late time can cause a shift in surface equilibrium, resulting in desorption of retained active surfactant agents and therefore, it is possible to obtain benefit from this phenomenon to achieve longer period of the lowest IFT condition while maintaining the amount of surfactant used. Hence, this study aims to evaluate effects of two-slug surfactant flooding compared to single-slug while maintaining amount of surfactant used constant in waterflooded reservoir. The performance is evaluated based on additional oil recovery using STAR® reservoir simulation program. Simulated results indicated that two-slug surfactant injection yields better oil recovery than conventional single-slug surfactant flooding due to benefit of sacrificial adsorption and desorption process of active surfactant. Selecting type of two-slug surfactant flooding strategy would depend on surfactant concentration of single-slug which is chosen for modification; whereas, the selection of magnitude of concentration contrast between two slugs would depend on placement of surfactant mass ratio
Understanding Internet User Profiles: A Case Study of Thailand
Get PDFThailand is experiencing the unforeseen growth in Internet penetration like in many developing countries. Internet users are eager to go online and try our new applications. In order to understand the whole picture of the market, it is important for one to understand the user behaviors first. This study aims to analyze the Internet user behaviors, using Thailand as a case study, and group the users according to their usage behaviors. The findings show four groups of Internet users which are different from traditional literature which has not been updated since 2012. They are, namely, (1) Online Hardcores, (2) Rational Users, (3) Social Addicts, and (4) Social Followers. These groups have different behaviors when it comes to the usage of different applications on the Internet. It is found that most Thai users use social network applications and short messaging services, such as Line and Whatsapp. Therefore, the majority tend to be the socializers. However, it was found that Thai users often use many applications in one day. They do not stay only on social networks but also use other programs as well. The results also show that Internet users grouping is still the area that can be further developed as the users and applications keep changing
SROI (Social Return on Investment) – A Case Study about Social Profit
Get PDFAbstract—In annual accounts and management reports, financial figures are used predominantly both in commercial and nonprofit companies in order to give a true and fair view of a company's assets, profits and financial position. As a result, the financial success is a key performance indicator – a figure which, usually, is quite low in the case of nonprofit companies [1]. However, such companies strive to reach content-oriented goals primarily, for instance performance quality, training success and employee satisfaction. As content-oriented goals are their basis of legitimacy, there should be possibilities to calculate whether they are met [2].
Basic prerequisite for such a calculation are specified details about the company’s mission statement, its content-oriented goals (from an economic, business, social or environmental point of view), its commercial goals (concerning profitability, liquidity and financial security) and its standards to measure objectives [3]. On this basis, it becomes possible to set targets and to incorporate the defined goals into a monitoring and reporting system [4].
Beyond achieving a profit, a social kind of success becomes interesting in such cases, which can be expressed as the so-called Social Profit. For example, this key figure can be measured by comparing costs and benefits attributed to the support of people in need. Benefits calculations takes avoided social spending into account, for example due to the prevention of homelessness, imprisonment or psychiatric clinic stays. The calculation also takes account of the effects of an individual’s rehabilitation and restored working abilities on the partaking in working and social life – which in the long run benefit society as a whole as well as tax payers [5].
Company goals, target groups, possible activities and their effects are of interest to calculate the Social Profit. However, several assumptions must be made about future political and economic developments. The following case study approaches to define and apply the concept “Social Profitâ€.
Index Terms: Content-oriented objectives, Impact, Legitimation, Private and public investments, Social economy enterprises, Social Profit, Social Return on Investmen
Older Adults’ Travel Website Usage and Their Wellbeing Perception
Get PDFAbstract—This study attempts to identify the impacts of older adults’ innovativeness on parasocial interaction, and examine the linkage between PSI and well-being perception. The 201 U.S. elderlyparticipated in survey conducted from online research survey firm. The conceptual suggested model was tested by the data collected from users of travel websites. The results found thatinnovativeness negatively influenced on PSI. Furthermore, older adults’parasocial interaction was found to generatetheir well-being perception. Managerial and academic implications and direction of future research were provided
Proximate Analysis and Phytochemical Properties of Sesame (Sesamum Indicum L.) Seeds Grown and Consumed In Abakaliki, Ebonyi State, Nigeria
Get PDFProximate and phytochemical compositions of Sesamum indicum seeds cultivated and consumed in Abakaliki, were determined. Abakaliki is the capital of Ebonyi State, one of the five south-eastern states of Nigeria. Sesame seeds are edible seeds which grow in pods. The fruit is a pubescent capsule grooved with a short triangular beak. Proximate analysis was carried out using the methods described by the Association of Official Analytical Chemists, A.O.A.C. (1997), while phytochemical analysis was carried out using the methods described by Harborne (1973). Sesame is principally cultivated in the northern part of Nigeria. However, bountiful harvest has been recorded recently in some southern states including Abakaliki, Ebonyi. This research was thus carried out to determine the effect of change in soil and climatic conditions on the nutritional contents of sesame. Proximate analysis indicated that sesame seeds contained 28.37% carbohydrate, 26.63% fats/oil, 23.32% protein, 7.37% moisture, 10.28% crude fibre and 4.02% ash. Determination of the phytochemical contents of the seed showed the presence of saponin (5.60mg/100g), alkaloid (4.80mg/100g), tannin (3.87mg/100g), phenol (13.83mg/100g) and flavonoids (18.03mg/100g). Statistical analyses showed that carbohydrates, fats/oil and proteins occur in significant quantities; an indication that sesame seeds possess high nutritive values. Also, the presence of significant values of some phytochemicals like flavonoids and phenol implies that sesame seeds are endowed with antioxidant and other medicinal potentials. Consumption of Sesamum indicum seeds is thus recommended as part of daily dietary intake due to the high nutritional and medicinal values