921 今天是世界环境清洁日
一早就和一群人去香港海边捡垃圾
呼吁大家减少浪费、减少塑料罐、塑料袋
再循环、再使用、减少 recycle,reuse,reduce
原来回收厂只是回收几个干净的罐子做成雨伞等
其他垃圾还是回到地球垃圾场-海洋
为了自己 为了下一代 一起努力吧!
Today is World Cleanup Day
Let’s keep the earth clean, use less plastic and less waste.
We clean the beach at Shek-O HK today!
What a meaningful day.
网络资料:世界清洁地球日
世界清洁日(英文原名:World Cleanup Day)是一个国际性的社会行动,致力于通过影响人类行为模式的改变以应对世界上的陆地失控垃圾以及海洋垃圾问题。这个行动源起于爱沙尼亚的Let’s Do It. 基金会,2008年他们首次行动即召集到了50,000多名志愿者在爱沙尼亚全境内进行一天的失控垃圾清理,这次行动为爱沙尼亚减少了大约10000吨非法的垃圾。[1]同时,世界清洁日也没有一个中心的组织机构,这项活动是在不同国家基层民众的努力之下达成的。世界清洁日的参与者主要以志愿者为主,同时非政府组织有时会帮助他们影响大众,协调活动,以及筹款。
中文名世界清洁地球日
节日时间 9月的第三个周末
节日类型纪念节日
节日活动清洁活动
节日意义 减少能源污染,维护地球的清洁
发展历史
1987年,澳大利亚人伊恩基南先生驾单人帆船环绕地球时,看到漂浮在海上的垃圾,深深觉得要做一些事。回到悉尼后,他在朋友的帮助下发起了“清洁悉尼港日”(1989)。这个活动召集了4000名志愿者清理废旧汽车,白色垃圾,玻璃瓶,烟头等。伊恩和他的委员会认为既然一个城市可以行动起来,整个国家也行,于是发动全国人民一起动手,最后在1990年有30万志愿者参与了新一轮的清洁澳大利亚日。迄今为止,清洁澳大利亚日已成功办了16年。
世界清洁地球日
下一步,伊恩又把眼光放到全世界。在得到联合国环境规划署(UNEP)支持后,世界清洁日在1993年第一次举办。自此,世界清洁日成为全球性社区活动,每年有超过130个国家,3500万人参与。
2016年,全球已经有113个国家采用其一日清洁模式推动国家间的环境清理行动。
2018年,适逢Let’s Do It. World发起10周年,Let’s Do It. World意欲推动全球150个国家在同一天进行清理行动,并将该计划命名为“2018World Cleanup Day”!
2018年9月15日,从最早日出的新西兰到最西边的夏威夷,全球158个国家17000000人,接力了人类历史上规模最大、参与人数最多的的垃圾清理环保马拉松。
和世界地球日一样,世界清洁日不是政治活动,它不属于任何党派或者政治团体,也不属于一个专一的意识形态。
中国的世界清洁日行动由捡拾中国项目团队在Let‘s Do It. World的授权后于2018年正式开启。
活动内容:清洁活动——传统的活动通常是一到两天的志愿者社区清扫活动;延伸计划——是对传统清洁活动的补充,包括植树,循环利用计划,生活垃圾处理设施的建立等;教育宣传——指导人们如何用积极正确的行为保护改善环境。
以下是某些生活废弃物在自然界停留的时间:烟头:1-5年,羊毛织物:1-5年,橘子皮:2年,尼龙织物:30-40年,皮革:50年,易拉罐:80-100年,塑料:100-200年,玻璃:1000年。[3]
World Cleanup Day (aka WCD) is a global social action program aimed at combating the global solid waste problem, including the problem of marine debris.
World Cleanup Day is celebrated with litter cleanup and waste mapping activities spanning every time zone. Environmental cleanup events are held in nearly every country until concluding near the international date line in Hawaii and American Samoa.
The 2019 World Cleanup Day will be held on the third Saturday of September and coincides in 2019 with Peace Day and the global climate strike (September 20-27).
#worldcleanupday
#fisherman
#blingblingocean
time zone mapping 在 Overwatch.blue Facebook 的最讚貼文
What Are Ground Control Points (GCPs) and How Do I Use Them?
A Guide to Using Ground Control Points with Drone Mapping Software
If you work with drone mapping software, you’ve no doubt heard talk of ground control points (GCPs). Used often in the surveying industry, as well as in virtual design and construction, GCPs greatly increase the global accuracy of drone maps. Although they are not necessary in every situation, GCPs are a vital tool for precision mapping. But what exactly are ground control points? And how do you go about using them correctly?
To help crack the code on ground control points, we’ve put together this short guide to using GCPs with drone mapping software.
What Are Ground Control Points?
So what exactly are ground control points? Ground control points are large marked targets on the ground, spaced strategically throughout your area of interest. If you use ground control points with your aerial map, you first need to determine the RTK GPS coordinates at the center of each. (We’ll explain how to do this a little later.) The ground control points and their coordinates are then used to help drone mapping software accurately position your map in relation to the real world around it.
It might be helpful to think of your GCPs as a series of thumbtacks placed on your drone map. Because the drone mapping software knows the exact location of each of these “thumbtacks”, it can reference their locations when it matches up all of the other points on the map.
When and Why Are GCPs Important?
When used correctly, ground control points greatly improve the global accuracy of your drone map. That is to say, they help ensure that the latitude and longitude of any point on your map corresponds accurately with actual GPS coordinates. This is important in situations where precision mapping and true global accuracy are needed. As we mentioned above, surveying companies generally use GCPs, because a high level of global accuracy is important in most of the work that they do. Virtual design and construction is another sector that often requires this level of precision drone mapping.
Landpoint, a surveying company based in Louisiana, uses ground control points when creating drone maps used for topographical surveying. Using GCPs on an 85-acre map, their team conducted an accurate aerial survey, saving over 80 man hours compared to traditional land survey methods.
Each drone mapping project is unique, and not all projects require a high level of global accuracy. Because of this, it is important to assess each project individually before you decide to take the extra step of using GCPs. But generally speaking, projects like geo-referenced overlays, design documents and land title surveys benefit from the use of ground control points. In an upcoming post, we’ll take a deeper look at which types of projects are best suited for using GCPs.
How to Construct a Ground Control Point
There is no one right way to make a ground control point. One important thing to remember is that the GCP must be easily visible in your aerial imagery. This is achieved by using high-contrast colors and by making sure the ground control point is large enough to be seen from your particular flight altitude. We generally recommend flying at 300 feet with a frontlap and sidelap of 70/75 when using ground control points. Keep in mind that this may change dependent upon the area you are mapping. Learn more by reading our recent post about mapping accuracy and reviewing our GCP support documents.
A number of companies do sell pre-made, portable ground control points. However, many drone users simply fashion their own.
This well constructed GCP was spray painted onto the concrete using a stencil. Notice that the marker is large enough to be visible from far away. A center mark helps eliminate any confusion as to where the center point is located.
If you’re unable to mark GCPs with paint, there are a variety of low-cost ways to make markers with items available from any local hardware store. The weather-resistant rubber and vinyl markers seen above end up costing about $5 each and are very durable.
Measuring the Location of Your GCPs
As we mentioned above, it is important to measure the GPS coordinates at the center of each ground control point. To do this, you need either a Real Time Kinematic (RTK) or Post Processing Kinematic (PPK) GPS receiver. Trimble and Leica products are commonly used for high-accuracy GPS measurements. New, lower-cost alternatives have recently come onto the market as well. Hiring a surveyor to measure the location of your ground control points is also an option.
Do not use a phone or tablet to measure the location of your ground control points. The accuracy of these devices is very similar to that of a drone’s onboard GPS system and will not deliver precise results. Instead, use one of the previous methods listed above, such as an RTK or PPK GPS receiver.
Best Practices for Using Ground Control Points with Drone Mapping Software
Of course, if you use ground control points with drone mapping software, it is important to use them correctly. Follow these best practices to help ensure your GCPs serve their intended purpose and improve the accuracy of your map.
Use a minimum of 4 large GCPs: DroneDeploy requires a minimum of 4 ground control points. Each should measure at least four feet. No more than 10 are usually needed for larger maps.
Evenly distribute your GCPs on the ground: For most maps of moderate size, we recommend 5 GCPs, one located near each corner and one located in the center, as pictured above. Also, make sure GCPs are spaced far enough apart, to avoid confusion. As a general rule, if you can see more than one GCP in an image, they are too close together.
Create a buffer zone around your map’s perimeter: We recommend a buffer zone between the edges of your map and any ground control points. This ensures there is enough image coverage to carry out reprocessing. The size of your buffer zone should be somewhere between 50–100 feet, depending on the overlap of your flight. A higher overlap produces more images and generally requires less buffer zone.
Be aware of elevation changes: If the area being mapped has noticeable elevation changes like hills, mines and valleys, make sure to place at least one ground control point on each of the different major elevations.
Make sure your GCPs are unobstructed: Visual obstructions like overhangs, snow, shade or glare make ground control points difficult to identify on your drone map.
Know Your EPSG code: Before processing your map in DroneDeploy, you must enter the EPSG code that relates to your GPS measurements. Choose your EPSG code by modifying the settings of your GPS measurement device. In most cases, we recommend using WGS84 (EPSG: 4326).
time zone mapping 在 Time Zones of the World Map (Large Version) - Pinterest 的必吃
Large world map showing all the time zones of the world. ... Time Zone Map, World Time Zones, Singapore Island, Singapore Travel, Honduras Travel. Twitter. ... <看更多>