全國中小學科展

2012年

A study to find out suitable colour to control pests of chilli plants using a colour trap

Chilli (Capsicum annuum L.) is one of the most important condiment crops in Sri Lanka. The main constrain in chilli cultivation is the Leaf Curl Complex (LCC) which reduces the quality of the pods as well as the yield. Many researches have been proven that the problem can be controlled by Integrated Pest Management (IPM) practices. Colour sticky trap is one of the mechanical methods in the IPM package which reduces the pest population successfully. Mainly three colours, namely blue, yellow and white have been identified as suitable colours for traps all over the world. This study was thus, conducted to find out the most effective colour for sticky traps to control chilli leaf curl complex in the Intermediate Zone of Sri Lanka. Traps were prepared from wooden plates of 30 x 25cm in size and the colours were applied in both sides of the plate. Both colourless and odorless vaseline was used as the sticky substance. These blue, yellow and white sticky wooden plates (traps) were fixed in 1m height from the ground level and they were used as the treatments. Six pots with 2 plants each of the variety ‘KA-2’ were used in a treatment and three replicates were sited for the experiment. All the agronomic practices were equally done for all the treatments. Number of trapped pests associated with the LCC was counted in 4, 6, 9 and 12 weeks after transplanting. The number of leaves affected by the pests in a canopy was counted in 7, 10 and 12 weeks after transplanting. The number of damaged green pods and the pod weight were taken at harvesting. The mean values of the number of pests trapped in white, yellow and blue colour traps were 162, 160 and 38 respectively. The percentages of damaged leaves in a canopy at 7, 10 and 12 weeks after transplanting in the blue trap were 89.07, 98.00 and 100.00 respectively. Those values in the white trap were 87.37, 98.90 and 93.29 and in the yellow trap were 69.03, 87.26 and 82.26. Percentages of damaged green pod weight in the blue, yellow and white treatments were 66.63, 47.06 and 45.65 respectively. These results suggest that yellow and white colours are more effective in sticky traps in pest controlling to control chilli leaf curl complex in the Intermediate Zone of Sri Lanka. Further studies are required to confirm the results.

黑暗中的光芒-林下植物葉綠體囊膜電池

林下(陰地)植物長期生活在較少陽光的地方,卻依然欣欣向榮。因此,我們針對林下植物的葉綠體囊膜電池做討論,希望可以找出發電效率更高的葉綠體囊膜電池。

Comfortable Equipment for Pedestrians

The phenomenon of pedestrians nowadays is still found. Due to frequent walking, sometimes our legs feel tired and hard to move. This is become the basis for developing tools that are convenient for pedestrians. An easy tool for humans is needed for our activities, especially walking. The Synergy between our hands and feet provides a big and significant contribution to the appliance. Normally, the movement of our hand gets along with its motion with a different side of the foot. When the right foot step, then the left hand is swung forward, and vice versa. The tools can be developed by utilizing a variety of systems. The system includes the tools concentric wheel and axles system, spring system, and pulley system. The concentric wheel and axles system is useful in controlling the rope. Movement on the rope could activate the entire system on the appliance. Wheel that related with the hand is three times bigger than wheel that related with pulley that is applied on foot. Spring system is able to lighten the pressure of the foot with a given upward force, and able to provide downward force when the spring returned to its original position. While the pulley system on the tool used to provide mechanical advantage two times is also useful to lighten the pressure of the foot when walking. The tools can be designed with simple, and able to provide benefits to users. By trial and error, it shows that the tool is able to lighten human’s activity when they walk. The tool can be able to lighten the leg’s load by utilizing arm muscles work. Utilization of the arm muscles which helps to ease the pressure of the foot can provide more benefits. One of them is that it can strengthen the arm strength, so the tool can be used as sport equipment. Utilization of the tool can also be reserved for special people who have difficulty in walking due to an accident or birth with leg defect.

Fast Fabulous Flush

Water is very vital in our lives as we cannot live without it. However our world is now facing a serious problem. Owing to the increasing population, water resources are scarce. In recent years, we can see that droughts have been affecting millions of people around the globe. In the meantime, people in developed countries have been wasting huge amount of water for flushing the toilet. According to the US Environmental Protection Agency, 30% of household water goes toward flushing the toilet. Countries like China, US, Canada and UK are still using fresh water in flushing, consuming 190 million L of fresh water every day, not to mention the energy needed in pumping the water. In fact, it is not necessary to use so much water to flush away substances like tissue, hair, urine etc. The water we used is far more than we need. However, as we cannot control how much water is used when we flush, all water in the cistern is flushed away. Realizing the seriousness of water shortage and wastage in flushing, we tried to invent a device to conserve water by controlling the amount of flushing water used. Firstly, we study the principle of normal flushing system so as to understand why flushing cannot be controlled. Then, we tried to think of ways to control flushing. We have tried various methods and materials. After the 6-month testing and modification, we successfully invented Fast Fabulous Flush. It is a device which can be fit into existing cistern to conserve water. With our invention, users can control the amount of water flushed according to needs, so as not to waste unnecessary water. Our invention costs a low price which is no more than 2 US dollar. Also, it can be fit into existing cistern within 3 minutes with simple installation process. Most importantly, flushing water can be conserved effectively. It is estimated that around 200L of water can be saved per household every day.

Human Computer Interface

Contains two human-computer interfaces. The first is an interface for blind people to perceive visual sensations using his tongue. Images from a webcam is processed with artificial intelligence software and is placed as a sensory matrix under the tongue. Currently the sensor placed on the tongue is about 8x8 pixels. The sight and the taste divide similar areas on the cortex so the blind person can adapt very quickly to the image sent on his tongue as an electricity matrix. Taste buds are the second sensor matrix after the eyes(as resolution) is based on the same principle of the Braile code but the information is received by tongue and it's proportional with the image from webcam and the person can receive more informations. The second interface follows the intent of motion detection of a person with disabilities. It is based on processing the neural signal of the brain taken by an handmade encephalograph and processing them with a artificial intelligence on computer. The project contains hardware and software. This project tries to suggest that the human computer interfaces can be made to support people with disabilities.

A Physical Analysis of the Difference in Ungues of Insects on Types of Habitat

1. Purpose of the research While studying about insects for school club activity, we found that there are differences in several anatomical characters of the insects according their habitats. Especially, the unguis was different as whether the insect lives in water or on land. So we observed the structure of unguis of some insects by microscope, and physically analyze to relate with the habitat of each insect. 2. Procedures First, we read papers and books about insect morphology to study about insect's unguis. Then, we collected samples of Chironomus plumosus(larva), Neuronia regina(larva), and Carbula humerigera. After pretreatment of samples, we put them in the SEM (Scanning Electron Microscope), observed the unguis of each insect and took pictures. 3. Data First, the larva of Chironomus plumosus has prolegs with numberless hooks that has a certain arrangement and the same angle of 90º. They also has several tiny swellings around the hook. Next, the larva of Neuronia regina has pincer-like unguis which were sharp and bend, reminding the shape of a quadratic curve. Lastly, Carbula humerigera has two large, thick pincer unguis, its form same as the of Neuronia regina. The unguis are very sharp and faced towards the land. 4. Conclusions Both the aquatic insects and the terrestrial insects have structures in unguis developed to increase precision on land. Especially, the angle of unguis were all close to 90º. In addition, aquatic insects like the larvas of Chironomus plumosus or Neuronia regina have particular characters increasing friction force according to resist the flow of water.

海鱺血清濃度對海鱺鰭細胞成長的影響

本文以動物細胞培養方法探討培養基中添加海鱺血清(CS)來培養海鱺鰭細胞株(CF-2)的可行性。發現CF-2單層細胞培養在L15-10/0 (L15 添加10% FBS)、L15-5/5 (L15添加5%FBS及5%CS)、L15-2.5/7.5、L15-0/0、L15-0/1.25、L15-0/2.5、L15-0/5、L15-0/10及L15-0/20等培養基6天後,其細胞數分別為最初的4.16、10.8、12、0.97、4.9、5.64、8.14、11.36及9.72倍。細胞接種於L15-0/0、L15-0/1、L15-0/2、L15-0/4、L15-0/8及L15-0/16等培養基24小時後,其附著率則分別為23.1%、96.9%、94.8%、93%、84.5%及39.5%。 CF-2繼代後直接培養在28℃,L15-0/2培養基中,細胞附著及成長良好,5-6天後再以1對2進行繼代。目前已在L15-0/2培養基中培養12代以上,命名為CF-2cs。在1%-16%海鱺血清濃度下,其增殖能力隨濃度增加而增加。培養在pH 7.6、pH 7.3、 pH7.0及pH 6. 7 的L15-0/2培養基中發現pH7.0為其生長最適酸鹼度。CF-2cs對嘉蠟魚虹彩病毒(RSIV),文蛤呼腸病毒(HCRV)及淋巴囊腫瘤病毒(LCDV)等三種魚類病毒具有感受性。以90%L15-0/2及10%DMSO超低溫冷凍保存CF-2cs,解凍後細胞附著及生長良好並在2-3天後長成單層。此外,L15-0/2也可直接用來培養RGB及RSS兩種源自於玳瑁石斑及銀紋笛鯛的初代細胞。這些結果顯示海鱺血清可完全取代胎牛血清來培養魚類細胞。

探討生物材料對骨髓間質幹細胞成骨分化效率之影響

本實驗之目的在利用骨髓間質幹細胞 (Bone Marrow Mesenchymal Stem Cells, BMSCs) 培養為平台,篩選能提升BMSCs成骨分化效率的生物材料。實驗中利用osteogenic induction medium (OIM)使BMSCs朝成骨分化路徑進行,分別在第7(前期)、14(中期)、21(後期)天作Alizarin Red Stain assay(ARS assay)測定鈣沉積之效率作為評估標準,而後於平面上塗覆不同生物材料進行測試,根據實驗結果顯示,Gelatin主要在中期就可達到最高成骨分化效率,而PCL與HA到後期亦能顯著提高成骨分化效率。當進入3D立體成骨誘導試驗時,我們發現Gelatin、HA的複合材料能保持平面之特性且結合二者優點,並且更能有效提升成骨分化之效率。

智慧型日光燈節能系統

本研究以增進日光燈管使用效率為目標,設計出一套整合型的系統以減少不必要的浪費。我們將感知用的硬體設備與自行開發的軟體程式作結合,使系統能夠在感知到日光燈管的各種狀態後,做出相對應的處置。其狀況包含:1.無電時系統會警告,以避免誤判的情形;2.有電時燈管正常運作;3.有電時燈管閃爍或不亮,此時系統會切斷日光燈管的電力,並記錄資訊。以上述系統為基礎,我們搭配紅外線模組來達到有人在才開燈,無人時自動斷電;亦加入偵測環境用的光敏電阻來達到光線暗時才開燈,光線亮時會自動斷電。依據測試,閃爍的燈管會比正常燈管多消耗30%的耗電量,壞掉不亮的燈管亦會消耗正常燈管70%的耗電量,對能源越來越少的今天,我們的系統提供了另一種節能的機制。

Hourglass 2011

Over the past year Conor has been developing an electronic time keeping device named Hourglass. Hourglass has a three-fold focus on functionality, intuitive design and simplicity. To simplify the device he has limited the hardware to a bare minimum. Just three buttons and an LCD screen comprise the user-interface. Although this interface is simple, the user can access many features. These include intuitive scrolling menus, countdown, lap and alarm functions, accessed through button combinations as well as multiple ways to use single buttons, such as holding or short pressing. Many functions have been integrated into the device, such as a stopwatch with lap times, a countdown, up to 99 Custom Alarms with an individual active/inactive state and a lock/unlock feature. The stopwatch is accurate to 1 second and can be started, stopped, reset and used to record lap times. When laps have been recorded, the user can then take the time value of a lap and turn it into a countdown. A countdown of up to 99 hours can be set, and will run until deactivated or until it reaches zero. Upon reaching zero the alarm is activated. The home screen displays the time, any active countdown and notifies the user if an alarm is active. It can be locked or unlocked by holding the blue button a set period of time, helping to reduce any inadvertent change in setting. All of the functions available can be operated easily with the intuitive 3 button interface method. The menu system is simple, but has been set up through clever coding. An arrow indicated which option is selected, by pressing the top button on the clock the option above the current selection is selected/the menu scrolls up. Pressing the bottom button selects the next option in the downward direction/scrolls down. The button in the centre positioned off to the left is used to activate an option. When a Yes or No prompt appears on the screen, the action corresponds with the button position. Therefore the triangle layout of the buttons is simple and intuitive. Thus Conor’s device relies on complicated, yet elegantly formulated and annotated code and simple hardware interfaces to interact with the user in a way which is intuitive and provides great functionality. It does this while being simple and easy to understand. Here these principles are applied to a clock project, but there are implications for good design that go way beyond this context.