赤道儀刻度盤運用實務

2014-1-8‧赤道儀刻度盤運用實務 – 8cm之都會星空輕快日記 – PChome 個人新聞台.

2014-1-8赤道刻度盤運用實務
筆者追隨聖人的腳步,從小就很賤所以會做許多卑鄙的事情(論語:「吾少也賤故多能鄙事」)。

 Google  Yahoo! 搜尋「8cm排序第一就是本格推理。在網路搜尋極軸修正極軸校正)、光軸校正漂移法周期誤差追蹤精度像場旋轉< /span>等多項名詞,一樣會很容易找上本格推理,不必非用8cm搜尋不可。


  
http://www.youtube.com/watch?v=geQszAVWMok
How to use setting circles on a small telescope


現在赤道儀的使用和設計都是很奇怪的,天文廠和用家都忽略刻度盤的存在價值,既然稱作赤道,理應當該必有『測量』的機能作用,極軸校準後,即使沒有自動追蹤,也可以靠刻度盤讀取天体的座標,但是每家赤道儀的刻度盤都很小,沒有辦法滿足1000.5度視野的導入需要,甚至有的高級赤道儀沒有刻度盤(除非外接電子顯示刻度,否則不能算是赤道了)。如果有直徑20公分以上的刻度盤,對於已知座標天体的導入,是完全不需要尋星鏡的,當然也不需要什麼GOTO的。

  就算只是用極軸望遠鏡對極軸,只要有20公分以上的刻度盤,一樣可以將天体導入100視野中央區域,如果是筆者來設計赤道儀,刻度環會做到直徑40公分,然後在兩軸刻度上面標記所有主要亮星與梅西爾星雲的位置,這是從前就提過的事。

  因為筆者知道大家的作業精度到什麼程度,既然坊間從未有人對準過赤道儀極軸,請容筆者質疑一下,星圖上的天體座標可能與真實有些出入,這裡講的不是2000年分點之類的問題,而是這個測量精度是有限的,有點誤差也不奇怪的。 

  近年有些農田在重新鑑界的時候,因為測量精度提高了,新公佈的地界竟然推移了十幾二十公尺也是普遍的事,這下子自家的田跑到了鄰居(甚至是鄰居的鄰居)地上,但這是農家之間彼此心裡有數就好,各家還是繼續按照既有地界耕作。星空的鑑界作業也是會有一樣的問題,連赤道儀極軸都未曾對準的話,至少赤道座標的經緯線走向就會偏差,但是這樣的鑑界誤差不會有農田那麼嚴重。 

  筆者求學時就常利用小學生作業用的三角板、量角器進行土地建築的現場測量,進入社會後會以辦公室的邊長26cm地磚作為參考練習步測,因此筆者在步測的時候是每步26cm,步測幾公尺寬的陽台時,誤差在5%以內,當然距離越長就越準確。有次陪同稅官觀察加油站土地,結果找不到加油站面積資料,筆者就試著進行步測(加油站土地不是正方形),結果心算一下估計是975平方公尺(全程沒有使用筆記和電子計算機),後來在資料裡找到了登記面積資料,記載加油站是1,000平方公尺(是整數的),當然加油站的水泥地面面積會微略小於所有地面積(1,000平方公尺),所以筆者測量到的比1,000平方公尺略小也不奇怪。 

  筆者記得那位稅官高興死了,說每次都找筆者來就好了,因此筆者不太需要什麼牽拖配件的,進行土地建物測量時也是一樣,主要是靠勤練技術。  

  如果是要導入亮星,那麼在100倍以內是不需要尋星鏡就能一次導入視野,這是最基本的練習,連這種事情都要提醒,筆者也覺得難堪,但真的有些入門玩家連30倍也搞很久,結果還是無法導入而放棄。其實筆者也遇過一回多次無法導入只好放棄的情況,但那是300倍且沒有尋星鏡輔助的狀況。


http://www.youtube.com/watch?v=UPoh76f60kA
Top 20 Astronomy Tips

 

 

台長:8cm

Install GUI on debian 7 wheezy – Nam Huy Linux Blog

Install GUI on debian 7 wheezy – Nam Huy Linux Blog.

This article will show you how to install GUI (Graphical User Interface) of your choice (gnome, kde, Cinnamon, mate, enlightenment, xfce, or lxde) on debian 7. The two biggest players in the game are Gnome and KDE, but there are also many smaller GUIs, like Xfce and LXDE that have just as much to offer.

Download Debian 7 wheezy

For leaner and better control of what you install on your machine, I highly recommend you to download and install debian minimal CD or netinst.

x32 http://cdimage.debian.org/debian-cd/7.2.0/i386/iso-cd/debian-7.2.0-i386-netinst.iso

x64 http://cdimage.debian.org/debian-cd/7.2.0/amd64/iso-cd/debian-7.2.0-amd64-netinst.iso

When you are at “Software selection” screen, *unselect* all the option.

Gnome

GNU Object Model Environment (Gnome) is a desktop environment and graphical user interface that runs on top of a computer operating system, user-friendly desktop for Unix operating systems, based entirely on free software.

You will need to install aptitude and tasksel before install gnome

Aptitude is an Ncurses based FrontEnd to Apt, the debian package manager.

Tasksel is a tool that installs multiple related packages as a co-ordinated “task” onto your system.

# apt-get install aptitude tasksel

Install gnome on debian

# tasksel install gnome-desktop --new-install

KDE

K Desktop Environment (KDE) is a free desktop environment and development platform built with Trolltech’s Qt toolkit. It runs on most Unix and Unix-like systems, such as Linux, BSD and Solaris.

# apt-get install aptitude tasksel
# aptitude --without-recommends install ~t^standard$ ~t^desktop$ ~t^kde-desktop$

Or install KDE from the default repositorie
# apt-get install kde-standard

Compiz

Compiz is truly one of the original compositing window managers for the X Window System which is capable to make use of OpenGL-acceleration. The integration enables it to run compositing effects in window management, for example a minimization effect and a cube workspace. Compiz conforms to the ICCCM standard together with replacement for the main Metacity in GNOME or KWin in KDE.

# echo "deb http://ftp.us.debian.org/debian/ sid main non-free contrib" >> /etc/apt/sources.list
# echo 'APT::Default-Release "testing";' >> /etc/apt/apt.conf
# apt-get update
# apt-get -t sid install compiz compiz-fusion-plugins-extra compizconfig-settings-manager
# compiz --replace

You can configure Compiz via CCSM utility. located in System -> Preferences -> CompizConfig

Cinnamon

Cinnamon is a Linux desktop which provides advanced innovative features and a traditional user experience. The desktop layout is similar to Gnome 2. The underlying technology is forked from Gnome Shell. The emphasis is put on making users feel at home and providing them with an easy to use and comfortable desktop experience.Cinnamon has rich visual effects enabled by new graphical technologies.

# echo deb http://packages.linuxmint.com/ debian main import backport upstream romeo >> /etc/apt/sources.list

# apt-get install linuxmint-keyring

# apt-get update

# apt-get install cinnamon

MATE

The MATE Desktop Environment, a non-intuitive and unattractive desktop for users, using traditional computing desktop metaphor. MATE is based on old Gnome 2, which is stable, tried and true. Because of it has been around for so much longer, tools have been developed for it which makes Gnome 2 highly compatible with most software and also highly configurable (for example, you can run Compiz on it).

Add one of MATE repositories to your source.list

# nano /etc/apt/sources.list

# main repository

deb http://repo.mate-desktop.org/debian wheezy main

# mirrors

deb http://packages.mate-desktop.org/repo/debian wheezy main

deb http://mirror1.mate-desktop.org/debian wheezy main

Install MATE on debian

apt-get update

apt-get install mate-archive-keyring

apt-get update

# Now to install MATE choose 1 of the 3 apt-get lines below.

# this installs the base packages

apt-get install mate-core

# or this to install mate-core and more extras

apt-get install mate-desktop-environment

#or this to install mate-core + mate-desktop-environment and even more extras.

apt-get install mate-desktop-environment-extra

Enlightenment

Enlightenment is not only one desktop environment for Linux, but it has an entirely libraries to assist you to produce gorgeous end user interfaces together with a lesser amount of computer resource as compared to doing it the particular traditional way, it also helping together with classic toolkits, not forgetting an old-fashioned window manager.

$ wget -c www.debe17.com/debian/debe17-svn_1.1.1-0_all.deb

# dpkg -i debe17-svn_1.1.1-0_all.deb

XFCE

Xfce is a lightweight desktop environment for UNIX-like operating systems. It aims to be fast and low on system resources, while still being visually appealing and user friendly.

To install Xfce on debian 7 wheezy
# apt-get install xorg xfce4 xfce4-goodies thunar-archive-plugin synaptic gdebi wicd

To install extra XFCE packages
# apt-get install xdg-utils xfce4-power-manager xfce4-goodies htop bzip2 zip unzip unrar-free

LXDE

The LXDE or “Lightweight X11 Desktop Environment” is an extremely fast-performing and energy-saving desktop environment. LXDE uses less CPU and less RAM than other environments. It is especially designed for cloud computers with low hardware specifications, such as netbooks, mobile devices (e.g. MIDs) or older computers. LXDE can be installed on many Linux distributions including Debian, Fedora, OpenSUSE and Ubuntu.

minimum set of elements
# apt-get install lxde-core

complete set of elements
# apt-get install lxde

complete Debian LXDE desktop environment
# apt-get install task-lxde-desktop

醫ZONE – 陳延珮: 四種常見的兒童傳染病 shared via My730HK

醫ZONE – 陳延珮: 四種常見的兒童傳染病
http://www.am730.com.hk/column-187653
shared via My730HK
水痘、麻疹、流行性腮腺炎及德國麻疹是4種經感染過濾性病毒而引發的常見兒童傳染病,傳播性高,嬰幼兒感染後,有機會導致嚴重的併發症。部分如患德國麻疹的兒童,若將病毒傳播到未接種疫苗的孕婦,更可能因此令她們的胎兒出現先天性器官缺陷或畸形。
這4種常見兒童的傳染病主要都是因接觸患者的飛沫、或呼吸道分泌物而受感染。以水痘為例,患者可在感染病毒後10至21天後發病,包括發燒、全身長出痕癢紅疹、水泡等徵狀。麻疹患者受感染後,會出現高燒、咳嗽、眼結膜充血等,若不及時治療,患者可能會腦部受損、失明或失聰,甚至死亡。
流行性腮腺炎(即「生痄腮」),由腮腺炎病毒所引起,主要影響唾腺,徵狀主要為唾腺腫痛(通常集中在兩頰)。部分嚴重個案可導致聽覺受損、腦膜炎以至男士睪丸發炎等後遺症。
德國麻疹又被稱為「風疹」,患者受病毒感染後,會出現發燒、疲倦、耳後淋巴結明顯腫大,以及全身性不規則丘疹等徵狀。此症最可怕的,是當未有免疫力的孕婦受感染後,會增加胎兒出現先天性缺陷、甚至畸胎等嚴重後果。
隨著相關的疫苗陸續研發及應用,除了分開式注射兩劑MMR (麻疹、流行性腮腺炎及德國麻疹)及兩劑水痘疫苗外,兒童可選擇於12及15個月大注射兩劑的四痘混合疫苗,一次過預防水痘、麻疹、流行性腮腺炎及德國麻疹4種傳染病。
家長可向醫生查詢更多有關疾病預防及疫苗注射的資料。
作者為兒科專科醫生