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熱門關鍵字: the king 水果 豆漿 電腦
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Enhancement of Online Stochastic Gradient Descent using Backward Queried Images

Stochastic gradient descent (SGD) is one of the preferred online optimization algorithms. However, one of its major drawbacks is its predisposition to forgetting previous data when optimizing through a data stream, also known as catastrophic interference. In this project, we attempt to mitigate this drawback by proposing a new low-cost approach which incorporates backward queried images with SGD during online training. Under this new approach, we propose that for every new training sample through the data stream, the neural network is optimized using the corresponding backward queried image from the initial dataset. After compiling the accuracy of the proposed method and SGD under a data-stream of 50,000 training cases with 10,000 test cases and comparing our algorithm to SGD, we see substantial improvements in the performance of the neural network with two different MNIST datasets (Fashion and Kuzushiji), classifying the MNIST datasets at a high accuracy for the mean, minimum, lower quartile, median, and upper quartile, while maintaining lower standard deviation in performance, demonstrating that our proposed algorithm can be a potential alternative to online SGD.

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Autonomous Vehicle

This is the self-driving and navigating vehicle which follows a track. This robot is made by our group. We made this robot together assembling the parts. This robot is commonly used in industries to shift goods and product. In this robot we have arranged all the things also metal detector which buzz when a metal is detected under it. This robot helps a lot in industrial life and is also easy to make if we learn the steps. This robot also needs programming to make it work. The programming software used for it is known as Arduino IDE. This is the figure of this robot in industries. Here the people are keeping goods in the pickup and shifting them. This robot can also run in white track, only if we do the programming right for the white track. Nowadays in cars too this type of system is used like example: Tesla model X. In the car this system is used and to avoid the obstacles something named Lidar is used. To make this vehicle follow its track and the motor to run different things are used like IR Sensor, and L298N motor driver module respectively.

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Biodegradation of Post-Cured Photopolymeric Resin of Stereolithography 3D Printers Using Galleria mellonella Larva.

The present research has as main objective to degrade the post-cured photopolymer of the stereolithography 3D printer resin using Galleria mellonella larvae. It is necessary to consider that the use of materials from 3D printers tends to increase considerably and in approximately seven years about 10% of everything that will be produced in the world will come from this type of printing. Considering also that the increase in population growth and technological development are directly linked to the increase of solid waste on the planet, in particular to polymeric materials, there is a need to degrade and give an adequate end to waste, avoiding a notorious accumulation along the time. For this purpose, Galleria mellonella larvae will be used because of it's comprovated capacity to degrade polyethylene, to find out if it is capable of biodegrading the post-cured resin of the printer. To carry out the research, compositional tests were done in partnership with the SENAI Institute for Innovation in Polymer Engineering, located in São Leopoldo, Rio Grande do Sul, and the creation of the larvae and degradation of the photopolymer will be carried out in partnership with the University Federal University of Health Sciences of Porto Alegre (UFCSPA). The data analysis will be based on the crystallinity determination tests by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and attenuated total reflectance spectroscopy (ATR) that will also be applied in the larvae feces after contact with the polymer to assess for degradation. As a result of the compositional tests, the ATR showed predominantly characteristic absorptions of acrylic resin; in the TGA test, the loss of mass described in the test is related to the loss of mass of organic material, mainly polymer. Finally, in the DSC test a thermal event was observed in the heating of the sample, with peaks at 125 ° C (Tpm), characteristic of fusion, and a thermal event in the cooling of the sample, in 112 ° C (Tpc), characteristic of crystallization. Based on the analysis of the results obtained, it is possible to infer that most of the composition of the photopolymer is acrylic resin, widely used in stereolithography 3D printers. The research has the future objective of isolating the substance into the larvae responsible for degradation so that it can be degraded on industrial scales. The research started in March 2020 and is still under development due to the COVID-19 pandemic, which compromised the planned tests.

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What is the relationship between angular velocity and power efficiency of a twin blanded single rotor helicopter system, in hover?

A traditional helicopter requires 60 - 80% more power to hover than when in forward or lateral flight, making the manoeuvre extremely power inefficient. To maximise efficiency, industrially many properties of the helicopter and rotor have been changed and tested, for example: optimising blade shape, fuselage shape and changing weights of different helicopter components. This report in particular aims to find a relationship between power efficiency and angular velocity for a twin bladed hovering helicopter with a single rotor. The angular velocity of a blade measures the frequency of its revolution about a fixed point. A theoretical approach was first taken and then justified with empirical data. Firstly, a model for power efficiency was derived with William Froude’s momentum and blade element theory. The efficiency equations incorporated the thrust and power coefficients. Therefore, the research focused on determining values for these coefficients by manipulating equations, using industrial specifications and simulations from the XFOIL software. In order to validate the accuracy for such theoretically generated data, an experiment was conducted for a comparison. The theoretical and empirical data were concurrent, as they followed a similar trend and the empirical values overlapped within the theoretical error bars. The power efficiency for different angular velocities were then found by substituting values for the coefficients. The results demonstrated a positive relationship; where, as angular velocity increases, power efficiency increases too, then plateaus and repeats the same trend once again. The research raises many questions and could be extended by determining if a similar relationship exists for tri-copters and quadcopters.

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LENS WITH VARIABLE OPTICAL CHARACTERISTICS

Research work on creating a lens, the optical power can be changed depending on human needs. Most people have visual impairments that need to be corrected with surgery or optical devices (glasses and contact lenses). The optical characteristics of the human eye vary depending on age, health, intensity of visual load. We propose to give people the opportunity to smoothly adjust the optical power of the spectacle lens by changing the transparent tubes between the two windows of transparent films. Experimental studies have shown the possibility of adjusting the optical power of the proposed line in a wide range. Existing devices and materials for changing the optical power of the line are analyzed. The design of a lens with variable optical characteristics is proposed, which is created from two window films, the space between which is filled with liquid. Publicly available materials for the outer shell of the lens and liquid for its filling. The effect of the amount of liquid to be filled on the optical power of the lens was experimentally determined. The formula for experimental finding of focal length of a lens is entered. Novelty is impossible because you can use the lens in another field. For example, in the future it is planned to perform an experiment with a lens system to create, for example, a telescope.

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Mentor Hunt App

The Information Technology (IT) area has shown great growth in recent years, even with the economic recession that 巴西 has been through and the impact of the coronavirus pandemic. It is estimated that by 2024 the area will have a deficit of more than 290 thousand professionals. However, companies still face other difficulties in hiring, especially people who are looking for their first job in the Information Technology area. Most part of these difficulties are lack of qualified manpower and high prerequisites to fill internship or junior positions. As a result, the objective of this project is: to develop a platform that connects people who seek guidance, improvement or professional relocation in the Information Technology area with professionals that already have the experience they are seeking. The first step was a research and analysis of similar platforms in the market, whose proposal involves mentoring or professional connections, and it concluded that there are no services that fully meet the project’s proposal. In the second step, a research was done about mobile development, highlighting Flutter and Firebase platform. The third step defined the application’s features, such as suggestion of users and mentors, search for users, become a mentor, private chat, video calls, Portuguese and English languages, light and dark themes and profile customization. The suggestion of users and mentors is done by a match with the registered users, relating their areas of work (where the user has experience) and the areas of interest of each one. For the coding of the project, Flutter and Firebase technologies were used. To design the app, it followed Material Design specifications. For testing and distribution, the app was published on Play Store, Google’s Android application platform. The tests were performed by both the researcher and a selected group of users to verify if the functionalities were in accordance to what was defined in the beginning of the project. Perceiving the correct functioning of the application, the project achieved the proposed objective. In addition, it expanded its reach area, because it is possible to find users and mentors from any other area of the market.

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Phytochemical screening and evaluation of antiangiogenic properties of sapinit (Rubus fraxinifolius) fruit crude extracts

Plants are potential low-cost alternatives for cancer treatment. Rubus fraxinifolius or “sapinit” has been found to possess phytochemicals with anti-cancer potential. This project aimed to evaluate the antiangiogenic properties of methanolic R. fraxinifolius fruit crude extracts through the chick chorioallantoic membrane (CAM) assay. Through phytochemical screening, leucoanthocyanins, phenols, and tannins were detected. For the CAM assay, 10, 20, and 30 μg/μL extracts, distilled water, methanol, and retinoic acid were applied on 60 ten-day-old chicken eggs. The CAM photographs were analyzed using ImageJ Software. The mean percent inhibitions (MPI) of total length and vascular density from both analyses were subjected to One-Way Analysis of Variance (ANOVA). The ANOVA for the MPI of total length, followed by a Tukey post hoc test, show that only retinoic acid treatment has significantly higher MPI (p = 0.0010). Meanwhile, the results for the MPI of vascular density show no significant differences between all groups (p = 0.1630). It is possible that the concentrations used in the study may not be the concentrations needed to achieve optimal antiangiogenesis. The results may also be due to the absence of phytochemicals that exhibit significant antiangiogenic properties such as alkaloids. Lower concentrations and isolated phytochemicals may also be tested.

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Automated Inflation and Pressure Regulation for Recreational and Professional Cyclists

Cycling is a very popular mode of transport as well as a famous sport around the world. Many people enjoy this sport either professionally or recreationally. Cycling in the UK alone has grown up to 200% since lockdown in 2020. (Chandler, 2020) Cyclists make use of a broad selection of products to enhance their performance. Those products range from wireless gear shifting, advanced geometry, smart suspension. This project is aimed to indicate the importance of tire pressure and to introduce a product which will be able to adjust tire pressure while cycling. This product will give cyclist an advantage on different terrains as well as eliminate some common problems amongst cyclists. Flat tires are one of these problems. It occurs commonly amongst cyclists and can happen due to a variety of reasons. Another problem is wrongly inflated tires. This causes unnecessary loss in a cyclist’s power and speeds due to the high rolling resistance between the tires and the surface. This then results in losing time whether racing or commuting. In an article published in 2014 in Velonews.com, Lennard Zinn states: “Whether on tarmac or singletrack, a tire with lower rolling resistance reduces the power required to move forward while also providing a better quality ride. The tire absorbs small bumps by not transferring them into the bicycle and rider, resulting in a smoother ride, faster speeds, and better cornering." (Zinn, 2014) Taking this in consideration it becomes clear that it is important to develop a system which is able to control tire pressure.

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選擇相對論-探尋零元魔力的極限

消費者面對同類性質之高低價兩商品,當低價商品從原價降至零元,而高價商品同時等量降價時,消費者對低價商品之偏好將顯著增加,此現象稱為「零元效應」,因確定性效應、損失規避及稟賦效應造成。故本研究目的驗證零元效應的強度與成因,並實驗零元效應在不同消費領域、族群是否皆成立;設計不同族群受試者、實驗情況及品項分類,進行零元效應的極限測試。實驗具兩階段,形式分實際購買實驗及選擇實驗進行,其中皆設計各種變項之實驗組,對照其差異。實驗結果使用Wilcoxon 等級和檢定,並與 Dan Ariely (2007) 實驗結果進行比較,發現其差異不大;而在零元效應的極限方面發現除「必需品」外,其他品項皆存在零元效應,且受試者性別、年齡、地區不影響零元效應之強度。

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The influence of lanscape on nest preferences and behavior of twig nesting Hymenoptera

The occurrence and behavior of insects is significantly affected by the environment they live in. In this thesis, I dealt with the influence of structure of landscape on nesting preferences of Hymenoptera. For this comparison I had chosen to work with twig-nesting Hymenoptera, for which I have placed artificial nest opportunities into four biotopes – heath, edge of a heath, country lanes between fields and field. The studied location is located south of Znojmo near Podyjí national park. Particularly, I have focused on small carpenter bees of genus Ceratina. My results show that there is a big difference in the species distribution between the habitates of field and heath. The habitats of edge of a heath and country lanes make up a gradient between these two biotopes. The ecosystem of fields was preferred by a sphecid wasp Pemphredon lethifer and Ceratina cyanea. On the other hand, the ecosystem of heath was preferred by Ceratina chalybea, Ceratina nigrolabiata and megachille bee Hoplitis tridentata. I had also found out that in species that are more abundant on heaths, there is higher mortality of offsprings. Heaths were a place of the highest competition between species, as a result of which species with a lower body weight (Ceratina nigrolabiata) have been pushed into narrower twigs by larger species (Ceratina chalybea). I recorded a high number of nests in biparental bee Ceratina nigrolabiata, which were guarded only by mother in fields and country lane habitats. This may indicate that Ceratina nigrolabiata is only facultatively biparental, not strictly biparental as was considered until now.

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Modification of silica surface with supercritical water as a tool indicating new possibilities of existing separation methods

Silica capillaries have been an integral part of the instrumentation used in many areas of analytical chemistry for decades, especially in analytical separations. In most cases, they are used without treatment, occasionally forceless chemical surface treatments are made to suppress or enhance the activity of silanol groups. The aim of this work was to disrupt the inner surface of the capillary, perfectly smooth from manufactory, so that relatively coarse and various structures would be created, and to study their influence on the separation efficiency. The uniqueness of the used solution is based on the use of special properties of water exposed to high temperatures and pressures (supercritical water), which is able to disrupt this chemically inert material because of its aggressivity. In total, over 2000 experiments were carried out in order to define conditions suitable for the formation of various types of surface structures. Due to the high amount of resulting data, our own database application was created, allowing not only to save the picture of the structure and experimental conditions information, but also to clearly sort them out and create image reports according to the specified parameters. Samples representing individual types of structures were then selected from this database and a number of silica capillaries with a configuration suitable for electromigration analyzes were prepared. The creation of a structured surface in the input part of the separation capillary enabled the separation of some classes of substances and biosamples, which cannot be analyzed on standard capillaries with a smooth surface. An example is the complete separation of two strains of Staphyllococcus aureus bacteria (MRSA and MSSA), or the use of the absorbing capabilities of a structured surface to study the interactions of these bacteria with bacteriophages. This ability was also used in the determination of Aspergillus fungus in a sample taken directly from the patient's lungs, where there was achieved a significant increase in the sensitivity of the analysis. Structured capillaries can also be used in the analysis of food samples, i.e., for the separation of β-lactoglobulins A and B in cow's milk, which belong to its main allergens.

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實驗室裡的飛行荷蘭人--複雜蜃景之探究 (Fata Morgana: the explanation of the 'Flying Dutchman')

複雜蜃景(Fata Morgana)專指擁有多重影像的特殊上蜃景,形成於高緯度海面上,也是「飛行荷蘭人」的主要成因。本研究主要藉由探討介質折射率梯度變化與觀察者高度位置等變因,釐清複雜蜃景形成與觀察的最佳條件。藉由控制高濃度糖水溶液擴散形成的密度梯度,我們在六十公分的水缸中重建出形成複雜蜃景的環境,主要是因為糖水溶液中的折射率梯度遠大於海面上空氣的逆溫梯度所造成之折射率變化。為了進一步解析光在複雜折射率介質中之行進模式,我們以綠雷射光入射糖溶液,在側向以相機紀錄光的行進軌跡,分析探討其折射現象。我們同時利用相機觀察放置於水缸另一側的模型船,藉以觀察實際蜃景的形成與演化。本研究中我們另發展一套光軌跡的模擬程式,以協助實驗的進行與驗證實驗的成果。藉由實驗與理論模擬相互映證,充分探討複雜蜃景的成像與形成的最佳條件。

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