Friday 27 May 2011

Bagimana Kita Belajar Kepada Para Peraih Nobel?

In many ways, the Nobel Foundation is similar to an investment company, in that it invests Nobel's money to create a solid funding base for the prizes and the administrative activities. 

The Nobel Foundation is exempt from all taxes in Sweden (since 1946) and from investment taxes in the United States (since 1953).

Since the 1980s, the Foundation's investments have become more profitable and as of 31 December 2007, the assets controlled by the Nobel Foundation amounted to 3.628 billion Swedish kronor (c. US$560 million).
Untuk Mempelajari kehebatan para peraih nobel kita harus mengenal perjalanan kehidupan mereka, membentuk mental ilmiah yang kuat, serta membangun komunitas ilmiah di lingkungan kita. 

Sumber: 

Nobel Prize

Wikipedia.

Wednesday 18 May 2011

Presidential Lecture



Presidential Lecture

Kebutuhan Energi Kelistrikan Indonesia di masa depan 

(Oleh: Prof. B.J. Habibie)
 
 
Dalam keadaan mendesaknya masalah-masalah kehidupan kongkrit yang dihadapi bagian dunia yang masih terbelakang, tidak banyak gunanya menggolong-golongkan teknologi ke dalam 'teknologi sederhana,' 'teknologi menengah,' dan 'teknologi tinggi'. Jauh lebih berguna mempertanyakan teknologi manakah yang dapat memecahkan suatu masalah yang kongkrit, tanpa memperdulikan apakah teknologi yang tepat itu adalah teknologi primitif, menengah atau canggih, dan tanpa mempersoalkan di mana teknologi tersebut pertama kali dikembangkan.
~Prof. Habibie~ 


Unduh File PPTnya disini
 
 



Seiring dengan meningkatnya populasi penduduk dan tumbuhnya perekonomian, kebutuhan energi listrik terus meningkat. Pada 2030 mendatang, kebutuhan listrik akan mencapai sekitar 33,3 triliun kWh. Jumlah tersebut setara dengan lebih dari dua kali lipat energi listrik yang diproduksi pada 2005.

Bagaimana dengan Indonesia? Data yang dilansir www. detik.com menyebutkan bahwa pada 2025, kebutuhan batu bara untuk bahan bakar pembangkit listrik tenaga uap (PLTU) diperkirakan mencapai 150 juta ton per tahun. Sementara itu, tingkat konsumsi listrik akan mencapai 49 gigawat pada tahun yang sama. 


Produksi tenaga listrik, selanjutnya disitribusikan dan digunakan tidak lepas dari lingkungan hidup. Penggunaan bahan bakar untuk pembangkit listrik yang menghasilkan gas rumah kaca seperti karbondioksida tidak lagi dianjurkan. Karena, emisi gas rumah kaca telah menjadi kontributor peningkatan suhu bumi dan pemanasan global. 

Menghasilkan tenaga listrik dengan membakar batu bara, dan gas alam dapat meningkatkan konsentrasi karbondioksida sehingga meningkatkan efek rumah kaca dan pemanasan global. Tenaga nuklir juga akan berpengaruh negatif pada lingkungan hidup. Pembangkit listrik tenaga air (PLTA) sangat membutuhkan arus air dari bendungan untuk menggerakan turbinnya.

Banyak pihak yang mempromosikan penggunaan sumber daya lain untuk membangkitkan listrik seperti angin dan panas bumi. Sumber daya yang ‘hijau’ akan memberikan dua keunggulan utama, termasuk tidak menimbulkan polusi udara dan jejak karbon. 

Tenaga surya dan angin pun memiliki keterbatasan karena sumber daya ini tidak selalu tersedia. Dengan kata lain – matahari tidak selalu bersinar dan angin tidak berhembus setiap saat. Kelemahan lain adalah biasanya kedua sumber daya ini sulit didapat di daerah – daerah yang justru membutuhkan tenaga listrik. 

Integrasi pembangkit listrik dan tenaga ‘hijau’ ke dalam power supply, serta meningkatkan penghematan energi dan mengurangi puncak kebutuhan listrik, adalah alasan mengapa pemerintah, perusahaan teknologi, aktivis lingkungan hidup dan pendukung penghematan energi semakin memusatkan perhatian mereka pada upaya memodernisasikan grid-grid yang mendistribusikan listrik dari pembangkit listrik ke pelanggan. 

Agar kita menggunakan lebih banyak sumber energi yang ramah lingkungan dan mendorong transmisi, pendistribusian dan penggunaan listrik secara lebih canggih, grid-grid listrik harus berubah menjadi ‘lebih pintar’. Oleh karena itu, tantangan yang sebenarnya adalah membawa grid listrik dari abad ke-20 ke abad ke-21.

Saturday 14 May 2011

Kapal Luar Angkasa dalam Pengembangan


The proposed Crew Exploration Vehicle approaching the Moon
The proposed Crew Exploration Vehicle approaching the Moon
Sumber:

Wikipedia

Wednesday 11 May 2011

Indonesian Space Force Command

Indonesian Space Force Command
Komando 
Untuk Keamanan Luar Angkasa 
Dari Angkatan Antariksa Indonesia


“I am prepared to die, but there is no cause for which I am prepared to kill.” 
~Mahatma Gandhi~ 

 
Helicopter
An LAPD Bell 206
[hide]Part of a series on
Categories of aircraft
Supported by lighter-than-air gases (aerostats)
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Supported by LTA gases + aerodynamic lift
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Supported by aerodynamic lift (aerodynes)
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Unpowered fixed-wing Powered fixed-wing

Powered hybrid fixed/rotary wing

Unpowered rotary-wing Powered rotary-wing

Powered aircraft driven by flapping

Other means of lift
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A helicopter is a type of rotorcraft in which lift and thrust are supplied by one or more engine driven rotors. In contrast with fixed-wing aircraft, this allows the helicopter to take off and land vertically, to hover, and to fly forwards, backwards, and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft would not be able to take off or land. The capability to efficiently hover for extended periods of time allows a helicopter to accomplish tasks that fixed-wing aircraft and other forms of vertical takeoff and landing aircraft cannot perform.

Uses

Due to the operating characteristics of the helicopter—its ability to takeoff and land vertically, and to hover for extended periods of time, as well as the aircraft's handling properties under low airspeed conditions—it has been chosen to conduct tasks that were previously not possible with other aircraft, or were time- or work-intensive to accomplish on the ground. Today, helicopter uses include transportation, construction, firefighting, search and rescue, and military uses.

First flights


In 1906, two French brothers, Jacques and Louis Breguet, began experimenting with airfoils for helicopters and in 1907, those experiments resulted in the Gyroplane No.1. Although there is some uncertainty about the dates, sometime between 14 August and 29 September 1907, the Gyroplane No. 1 lifted its pilot up into the air about two feet (0.6 m) for a minute.[5] However, the Gyroplane No. 1 proved to be extremely unsteady and required a man at each corner of the airframe to hold it steady. For this reason, the flights of the Gyroplane No. 1 are considered to be the first manned flight of a helicopter, but not a free or untethered flight.

That same year, fellow French inventor Paul Cornu designed and built a Cornu helicopter that used two 20-foot (6 m) counter-rotating rotors driven by a 24-hp (18-kW) Antoinette engine. On 13 November 1907, it lifted its inventor to 1 foot (0.3 m) and remained aloft for 20 seconds. Even though this flight did not surpass the flight of the Gyroplane No. 1, it was reported to be the first truly free flight with a pilot.[n 1] Cornu's helicopter would complete a few more flights and achieve a height of nearly 6.5 feet (2 m), but it proved to be unstable and was abandoned.[5]

The Danish inventor Jacob Ellehammer built the Ellehammer helicopter in 1912. It consisted of a frame equipped with two contra-rotating discs, each of which was fitted with six vanes around its circumference. After a number of indoor tests, the aircraft was demonstrated outdoors and made a number of free take-offs. Experiments with the helicopter continued until September 1916, when it tipped over during take-off, destroying its rotors.[18]


Early development

In the early 1920s, Argentine Raúl Pateras Pescara, while working in Europe, demonstrated one of the first successful applications of cyclic pitch.[5] Coaxial, contra-rotating, biplane rotors could be warped to cyclically increase and decrease the lift they produced. The rotor hub could also be tilted forward a few degrees, allowing the aircraft to move forward without a separate propeller to push or pull it. Pescara was also able to demonstrate the principle of autorotation, by which helicopters safely land after engine failure. By January 1924, Pescara's helicopter No. 3 could fly for up to ten minutes.[19]
Oehmichen N°2 1922
 
One of Pescara's contemporaries, Frenchman Etienne Oehmichen, set the first helicopter world record recognized by the Fédération Aéronautique Internationale (FAI) on 14 April 1924, flying his helicopter 360 meters (1,181 ft). On 18 April 1924, Pescara beat Oemichen's record, flying for a distance of 736 meters (nearly a half mile) in 4 minutes and 11 seconds (about 8 mph, 13 km/h) maintaining a height of six feet (2 m).[20] Not to be outdone, Oehmichen reclaimed the world record on 4 May when he flew his No. 2 machine again for a 14-minute flight covering 5,550 feet (1.05 mi, 1.69 km) while climbing to a height of 50 feet (15 m).[20] Oehmichen also set the 1 km closed-circuit record at 7 minutes 40 seconds.[5]

In the USA, George de Bothezat built the quadrotor De Bothezat helicopter for the United States Army Air Service but the Army cancelled the program in 1924, and the aircraft was scrapped.

Meanwhile, Juan de la Cierva was developing the first practical rotorcraft in Spain. In 1923, the aircraft that would become the basis for the modern helicopter rotor began to take shape in the form of an autogyro, Cierva's C.4.[21] Cierva had discovered aerodynamic and structural deficiencies in his early designs that could cause his autogyros to flip over after takeoff. The flapping hinges that Cierva designed for the C.4 allowed the rotor to develop lift equally on the left and right halves of the rotor disk. A crash in 1927, led to the development of a drag hinge to relieve further stress on the rotor from its flapping motion.[21] These two developments allowed for a stable rotor system, not only in a hover, but in forward flight.

Albert Gillis von Baumhauer, a Dutch aeronautical engineer, began studying rotorcraft design in 1923. His first prototype "flew" ("hopped" and hovered in reality) on 24 September 1925, with Dutch Army-Air arm Captain Floris Albert van Heijst at the controls. The controls that Captain van Heijst used were Von Baumhauer's inventions, the cyclic and collective. Patents were granted to von Baumhauer for his cyclic and collective controls by the British ministry of aviation on 31 January 1927, under patent number 265,272.
In 1928, Hungarian aviation engineer Oszkár Asbóth constructed a helicopter prototype that took off and landed at least 182 times, with a maximum single flight duration of 53 minutes.[22][23]

In 1930, the Italian engineer Corradino D'Ascanio built his D'AT3, a coaxial helicopter. His relatively large machine had two, two-bladed, counter-rotating rotors. Control was achieved by using auxiliary wings or servo-tabs on the trailing edges of the blades,[24] a concept that was later adopted by other helicopter designers, including Bleeker and Kaman. Three small propellers mounted to the airframe were used for additional pitch, roll, and yaw control. The D'AT3 held modest FAI speed and altitude records for the time, including altitude (18 m or 59 ft), duration (8 minutes 45 seconds) and distance flown (1,078 m or 3,540 ft).[24]



 

External links

 
Organizations
Articles

  • The Helicopter 1953 video about uses and flight physics of helicopters. Prelinger Archives at the Internet Archive.
Information

Saturday 7 May 2011

Memahami Relativitas Umum Einstein

Relativitas umum (bahasa Inggris: general relativity) adalah sebuah teori geometri mengenai gravitasi yang diperkenalkan oleh Albert Einstein pada 1916. 

Teori ini merupakan penjelasan gravitasi termutakhir dalam fisika modern. Ia menyatukan teori Einstein sebelumnya, relativitas khusus, dengan hukum gravitasi Newton. 

Hal ini dilakukan dengan melihat gravitasi bukan sebagai gaya, tetapi lebih sebagai manifestasi dari kelengkungan ruang dan waktu. 

Utamanya, kelengkungan ruang waktu berhubungan langsung dengan momentum empat (energi massa dan momentum linear) dari materi atau radiasi apa saja yang ada. 

Hubungan ini digambarkan oleh persamaan medan Einstein.  


 "Reality is merely an illusion, albeit a very persistent one." 
*Albert Einstein* 


Referensi
Kunjungi Juga:

General Relativity

Sumber: 

The University of Cambridge

Wikipedia

To Be Continued

Wednesday 4 May 2011

Mekanika Orbit: Teknik-Teknik Praktis

"Teknik-Teknik Penerbangan Ke Luar Angkasa Mesti Segera Kita Pelajari Bersama" 
*Arip Nurahman*


Further information: List of orbits


Transfer Orbits

Transfer orbits allow spacecraft to move from one orbit to another. Usually they require a burn at the start, a burn at the end, and sometimes one or more burns in the middle. The Hohmann transfer orbit typically requires the least delta-v, but any orbit that intersects both the origin orbit and destination orbit may be used.

Gravity assist and the Oberth effect

In a gravity assist, a spacecraft swings by a planet and leaves in a different direction, at a different velocity. This is useful to speed or slow a spacecraft instead of carrying more fuel.
This maneuver can be approximated by an elastic collision at large distances, though the flyby does not involve any physical contact. Due to Newton's Third Law (equal and opposite reaction), any momentum gained by a spacecraft must be lost by the planet, or vice versa. However, because the planet is much, much more massive than the spacecraft, the effect on the planet's orbit is negligible.
The Oberth effect can be employed, particularly during a gravity assist operation. This effect is that use of a propulsion system works better at high speeds, and hence course changes are best done when close to a gravitating body; this can multiply the effective delta-v.

Interplanetary Transport Network and Fuzzy Orbits 
See also: Low energy transfers
It is now possible to use computers to search for routes using the nonlinearities in the gravity of the planets and moons of the solar system. For example, it is possible to plot an orbit from high earth orbit to Mars, passing close to one of the Earth's Trojan points.

Collectively referred to as the Interplanetary Transport Network, these highly perturbative, even chaotic, orbital trajectories in principle need no fuel (in practice keeping to the trajectory requires some course corrections). The biggest problem with them is they are usually exceedingly slow, taking many years to arrive. In addition launch windows can be very far apart.
They have, however, been employed on projects such as Genesis. This spacecraft visited Earth's lagrange L1 point and returned using very little propellant.

Sumber:

Wikipedia

Monday 2 May 2011

Mari Kita Mengoptimalkan E-Journal Badan Tenaga Nuklir Nasional



Logo Header Halaman

 

Jurnal Iptek Nuklir Ganendra

 

Jurnal Iptek Nuklir Ganendra merupakan jurnal ilmiah hasil litbang dalam bidang iptek nuklir, diterbitkan oleh Pusat Teknologi Akselerator dan Proses Bahan (PTAPB) - BATAN Yogyakarta. Frekuensi terbit dua kali setahun setiap bulan Januari dan Juli.
Lihat Jurnal | Terbitan Terkini | Daftar



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Buletin Alara

 

 

Buletin Alara terbit pertama kali pada Bulan Agustus 1997 dengan frekuensi terbit  tiga kali dalam setahun (Agustus, Desember dan April) ini diharapkan dapat menjadi salah satu sarana informasi, komunikasi dan diskusi di antara para peneliti dan pemerhati masalah keselamatan radiasi dan lingkungan di Indonesia.
Lihat Jurnal | Terbitan Terkini | Daftar



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Jurnal Teknologi Pengelolaan Limbah

 

 

Jurnal Teknologi Pengelolaan Limbah, diterbitkan oleh Pusat Teknologi Limbah Radioaktif - BATAN. Frekuensi terbit enam bulanan, pertama terbit Juni 1998. Alamat: Kawasan Puspiptek Serpong, Tangerang 15310, Indonesia.

Redaksi jurnal menerima naskah/makalah karya tulis ilmiah dari kegiatan penelitian dan pengembangan meliputi aspek aspek pengolahan dan penyimpanan limbah.
Lihat Jurnal | Terbitan Terkini | Daftar




 

Jurnal Sains Materi Indonesia

 

 

Jurnal Sains Materi Indonesia (Indonesian Journal of Materials Science), diterbitkan oleh Pusat Teknologi Bahan Industri Nuklir - BATAN. Terbit pertama kali: Oktober 1999, frekuensi terbit: empat bulanan.
Alamat Redaksi : PTBIN - BATAN, Gedung 43, Kawasan Puspiptek Serpong 15314 Tangerang

Lihat Jurnal | Terbitan Terkini | Daftar


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Jurnal Perangkat Nuklir

 

 

Jurnal Perangkat Nuklir (Journal of Nuclear Equepments), terbit dua kali setiap tahun bulan Mei dan November sejak 2007. Partisipasi aktif berupa saran dan pendapat maupun kritik yang bersifat membangun sangat diharapkan untuk meningkatkan kualitas jurnal. Alamat: Gedung 71, Kawasan Puspiptek Serpong, Tangerang 15310, Indonesia, Telepon: (021) 7560896, Penerbit: Pusat Rekayasa Perangkat Nuklir - BATAN
Lihat Jurnal | Terbitan Terkini | Daftar


Bila kita mampu membangun himpunan-himpunan peneliti kecil di tiap sekolah tinggi/kampus di Indonesia mengenai Iptek Nuklir ini, kemungkinan besar percepatan perkembangan ilmu pengetahuan Nuklir di tanah air akan semakin dahsyat dan masyarakat kita di kemudian hari dapat memetik manfaatnya.

Amin.


Sumber: Badan Tenaga Nuklir Nasional


Kunjungi juga:

http://www.batan.go.id/  (BATAN)

http://www.iaea.org/ (International Atomic Energy Agency)

http://nuclearscienceandtechnology.blogspot.com/  (Sekolah Sains dan Teknologi Nuklir)

http://masyarakatipteksindonesia.blogspot.com/2010/02/nuklir-indonesia_8979.html (Masyarakat Nuklir Indonesia)

http://www.sttn-batan.ac.id/ (Sekolah Tinggi Teknologi Nuklir BATAN)

http://ocw.mit.edu/courses/nuclear-engineering/ (Nuclear Engineering OpenCourseWare from MIT)

http://fisika.upi.edu/ (Jurusan Pendidikan Fisika, FPMIPA Universitas Pendidikan Indonesia)



Ucapan Terima Kasih Kepada:

Kak Rezy Pradipta, Ph.D. (Alumni Tim Olimpiade Fisika Indonesia, Belajar di Department of Nuclear Engineering at MIT)

Dr. Mohamed Mustafa ElBaradei, J.S.D. (Former Director General of IAEA)

Prof. Mujid S. Kazimi, Ph.D. (Director, Center for Advanced Nuclear Energy Systems MIT)

Prof.Djarot Sulistio Wisnubroto, M.Sc., D.Sc. (Presiden BATAN)

Kak Iqbal Robiyana, S.Pd. (Founder Center for Nuclear Education at Indonesia University of Education)

Dr. Petros Aslanyan, M.Sc. (Joint Institute for Nuclear Research, Rusia & Yerevan State University)

Semangat Semoga Bermanfaat

Sunday 1 May 2011

On the Moon Educator Guide

Audience: Educators
Grades: 3-12 and Informal
Product Number: EG-2009-02-05-MSFC



NASA is one of the largest employers of engineers in the world. "Design Squad®," an award-winning TV show that airs on PBS, engages teams of students in imaginative engineering challenges. Together, NASA and "Design Squad" have developed the On the Moon Educator Guide. The guide brings hands-on engineering and the adventure of space exploration to life for students. The activities are related to NASA's Lunar Reconnaissance Orbiter and NASA's Lunar Crater Observation and Sensing Satellite missions. In this guide, students are challenged to design and build:
  • An air-powered rocket.
  • A shock-absorbing system that will protect two marshmallow "astronauts."
  • A rubber band-powered rover.
  • A cardboard crane for maximum load-lifting ability.
  • A paper cup modified so that it can carry a marble down a zip line and drop a marble onto a target.
  • A solar hot water heater to cause the greatest rise in temperature.
On the Moon Educator Guide  [8MB PDF file]

Individual sections:
Introductory Pages
Launch It
Touchdown
Roving on the Moon
Heavy Lifting
On Target
Feel the Heat
Additional Resources

Online Training for Teaching Hands-On Engineering Activities with NASA and "DESIGN SQUAD®"

NASA and "DESIGN SQUAD®" have developed an online workshop for educators and afterschool leaders to build their skills and confidence in guiding kids through engineering activities like those from the On The Moon Educator Guide.

Completing this self-guided online workshop will allow educators to gain insight and strategies for strengthening critical-thinking skills and exciting their students about using the design process to arrive at solutions.
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