Equipping, programming and testing a robot searching for an avalanche transceiver
1. Purpose of the research Because we live in a famous winter sport region in Switzerland, we have been confronted with the problematic of avalanches since we were born. In winter 2011/2012 alone, 179 people were involved in an avalanche accident, of whom 25 died. The most important device for searching and rescuing a buried person is the avalanche transceiver. It creates an electromagnetic field, which can be used to locate a buried person with another transceiver. The most important factor while searching is time: After 30 min. the chance of survival of a buried person has dropped to 40%. Considering the fact that people often make mistakes when they are put under such a big stress, valuable time gets lost. This is where our project comes into play. With an automation of the searching process a fast and reliable search should be achieved. The aim we agreed on for this paper is to develop a prototype of a robot that can find an avalanche transceiver automatically and reliably. To study and optimize the functionality of our robot more easily, our tests have only been performed on flat ground. 2. Procedures The components of an avalanche transceiver with only one transmitting antenna are used as a receiver. With the help of this receiver, the signal of a transmitting avalanche transceiver was analysed. Furthermore, the results were used to evaluate the most suitable search technique. Our robot is based on the “RP6” robot system, which is programmable in the C-language. The signal of the receiver is modified in a way which allows the robot to read it. Based on the results of the signal analysis, a search algorithm is developed. In the final tests the robot was examined as to its functionality and efficiency. Therefore, the robot was positioned at randomly chosen starting points to locate the transmitting device. 3. Data The transmitter could be located correctly in every test. The starting points were successfully located up to 11 m from the transmitter. The search ending points were found at a maximum range of 0.5 m from the correct position. 4. Conclusions In view of the results, the aim of developing an automatic localisation of an avalanche transceiver on flat ground as a prototype is seen as fulfilled. Outside the specified range, the transmitter can only be located unreliably. This is due to the fact that outside that range the signal differential in different directions is too small to be processed by the robot. Our prototype was tested under ideal conditions. Certainly, our robot is still some way from being ready for use in an actual avalanche. Many different questions have not been answered yet or have come up during this project, for example: ‘How should the robot should be applied on uneven terrain?’ or: ‘How should it deal with several buried people at once (multiple transmitted signals)?’ Two aspects of our prototype, the low weight and the low construction costs, however, are particularly favourable.
蟹狀星雲的擴張
By comparing eight different epoch images of the crab nebula taken through 1942 to 2004, we have calculated the expansion velocity of 27 optical bubble features and 60 filaments. The mean expansion velocity of bubble features and filaments is 0.173 arcsec/yr and 0.15 arcsec/yr, respectively. We also estimated the maximum radial velocity of the expansion by analyzing the emission spectrum of the nebula. The maximum radial velocity is 1385.5 km/s. Combining these measurements indicates that the crab nebular is approximately 5870 light year away. In addition, if we assume that the nebula has been expanding at a constant rate, our expansion velocity projected backward indicates the mean date of the supernova event as A.D 1124, more than 70 yrs later than the accepted date of 1054. The result confirms the well-known acceleration in the crab's expansion. Although we have analyzed eight images with a 62 yr baseline, the acceleration still can't be derived from this study. 透過量測由1942年到2004年之間八張不同年代的蟹狀星雲中爆炸後殘骸的位置變化，可以計算出蟹狀星雲爆發的擴張速度。本研究選定了27個包狀物和60個纖狀物，計算出的擴張速度分別為0.173 arcsec/yr.和0.150 arcsec/yr。再透過分析蟹狀星雲的光譜所計算出的徑向速度（radial velocity）為1385.5 km/yr，進而推得蟹狀星雲的距離分別為5430光年和6370光年，平均值為5870光年。 另外，如果假設擴張速度是等速運動，那麼把求得的擴張速度倒推出的爆發日期是在西元1124年，這比中國紀錄中超新星爆發的1054年晚了70年。這顯示出蟹狀星雲的確非等速擴張而是有加速度的狀態，才會造成以等速倒推發生日期時，晚了70年。雖然本研究中分析了相差62年之久的八張影像，仍然無法分析出星雲的擴張的加速度情形。
Universal computing sorting machine
The purpose of the study was to develop and create a semi-automatic multi-purpose sorting and counting machine of standard articles. Currently, there is a problem of equipping industrial enterprises as well as small trade companies and large retailers with computing sorting machines of standard products of a certain shape. We would like to fill this missing link up with a simple, compact and inexpensive device. Procedures The proposed research consisted of a consistent design of a virtual model of the device and its electronic-mechanical implementation. The virtual model is simulated by a computer program "SolidWorks" object, which graphically shows the operation of the future device. In the development of the computing sorting device standard electronic devices and their associated software have been used. The created simplified real model demonstrates the basic principles and characteristics of the proposed device. Data As an example for the implementation of the concept device a computing device for sorting coins, in circulation in Russia has been created. As a basic principle of sorting objects by their geometric and weight characteristics were used. It is important that the device is focused on the correct form of the objects of sorting (balls, rings, coins, regular polyhedrons, screws, nuts, etc). To confirm the effectiveness of the computing device of this type of sorting, a series of tests of counting of objects manually have been carried out . The effectiveness of the device is determined by comparing the time characteristics of manual and automatic sorting. Findings and conclusions As a result of research and work performed, we have concluded that: 1) The proposed device can be used in various industries. (for example, while sorting ball bearings.) 2) Such a computing sorting device may find it's application in various commercial enterprises: to assist cashiers in retail ATMs. 3) Can be used in payment terminals. 4) 4) After a certain modernization of the device it can be used for money encashment.
漂浮的油滴--CMC 的測定
Surfactants have a great effect on decreasing the surface tension in aqueous solution and thus they are important components in detergents. The present study aims to explore the cleaning mechanisms of the substances for greasy subjects such as bowls and clothes. The roles of various surfactants that have on the changes in the surface tension of aqueous solution in the presence and absence of additives such as tea and salt have been carefully studied by using a lab-made equipment. We carefully observed the changes in the oil droplets after pushing oil in a syringe to the aqueous\r solution containing surfactants and additives. With decreasing the surface tension of the aqueous solution, the size of the droplet becomes smaller. By using this simple lab-made equipment, we are able to determine the critical micelle concentration (CMC) of sodium dodecyl sulfate (SDS), with a result of 0.0079 M at 20 ℃. The result is in a good agreement with the literature (0.0077M). With decreasing temperature and adding salts such as sodium sulfate, the decreases in the surface tension have been confirmed by our simple experiments. This simple equipment also allows study of the effects of impure additives such as salt, tea, vinegar that have on the changes in the surface tension of aqueous solution containing commercial detergents. We have found that most of the additives have a great effect on reducing the surface tension of the aqueous solution. The present study results suggest that the simple experimental set-up is practical for measuring the CMC of surfactants and for exploring the effects of additives on changes in the cleaning ability of commercial detergents.界面活劑性可有效降低水溶液的表面張力，因此，他們是清潔劑的重要成份。該實驗主\r 要在探討各種物質的清潔機制。利用自製的實驗裝置，針對各種不同的界面活性劑在添加了鹽類或茶水後界面張力的改變量，作詳盡的探討。我們將含有不同濃度界面活性劑以及添加物的水溶液裝入容器中，在推擠針筒使其的油通過針頭並進入該溶液後，我們仔細的觀察紀錄油滴大小的改變。結果顯示界面張力的降低會使得油滴變小。藉這個自製的裝置，在20℃下，本實驗所測得的陰離子型界面活性劑-十二烷基硫酸鈉之臨界微胞濃度0.0079M。結果幾乎與過去的文獻0.0077M 值符合。該實驗同時也證實了降低溫度，添加了鹽類後，可有效的降低界面張力。此外，此實驗裝置也可以用來測量市面上販售的清潔劑在添加了不純的物質後，其界面張力的改變量。我們發現大多數的添加物都能有效降低界面張力。目前的實驗結果顯示，這項實驗裝置在測定臨界微胞上有很高的實用性，同時也可以探討不同的添加物對市面上販售的清潔劑之洗淨力的影響。
死亡巧克力—切切割割好計謀
三角形的邊上取任意多個點，我們可以把這塊大三角形沿著切割線切割成較小塊的三角形，但切割線必須是點（或頂點）和點的連線，而且必須切割三角形，同時可以切任意大小的三角形，如圖（1）與圖（2）。但不可以一開始就取走整個三角形。定義拿到最後一塊三角形的人獲勝，而在多邊型中的玩法與在三角形中相同。 我們分A、B、C三種規則來討論，其中A規則即是上面提到的玩法，B規則大部分的玩法和A規則都相同，唯一不同的地方在於：A規則中，只要有一方取到剩下的圖形為三角形，另一方就可以直接取走剩下的三角形，而B規則規定即使剩下的圖形已經是三角形，也必須取到剩下的圖形邊上都沒有分點為止。C規則是限制玩家一次所能取的三角形數來進行遊戲。 我們完成了A、B、C規則中三角形與多邊形的必勝策略，並找出必勝策略之間的關聯。 ;Given any numbers of points on the sides of a triangle, the players can cut this triangle into pieces. Each cutting line has to be one, linked between two points given from two different sides. And the player can’t have to cut smaller triangles out of the original triangle. The out-cut triangles can be chosen randomly without any restriction in size, just like what’s shown in picture（1）and（2）. Meanwhile the first player can’t cut the original triangle exactly all out in the very beginning process. We define the player as the winner, who gets the last triangle. And the above way we play can be applies to any multi-side shapes. We discussed the question respectively in three rules, A, B, and C. Rule A is what we mention above. Rule B is generally the same as rule A, except for the only difference：The rule A , if there is any triangle left , the next player can get it directly, but while in rule B, the every next player has to cut out smaller triangles until no point is left on sides. Rule C proceeds on conditions that there is a limitation to a certain number of triangles cut out at a time. We has finished the winning tactic respectively in rule A, B, and C in the games with a triangle and multi-side shapes. Furthermore, we find the connection between the winning tactives.