Wednesday, March 13, 2013

BIOINTRUMENTATION ( INPUT TRANSDUCER )

Riddick "Online Input transducer Input transducers convert physical, chemical or biological phenomena to proportional electrical signals. There are two kind of input transducers : active tranducers which require electrical energy for their operation ( e.g. strain gauges). And passive transducer which do not require, but instead produce electrical energy. ( e.g. piezoeleectric transducers ). 3.1. Rotary motion and muscle displacement transducers Figure 7 shows an active transducer wich converts angular movement of a shaft to an electrical signal. A precision ball bearing allows the shaft to rotate with little fiction, and a small metal vane moves with the shaft within coils of wire. The reaction of the magnetic field around these coils to the metal vane creates variations of an electrical current in the coils, which may then be used by the remainder of the instrument system. The operation of this transducer is somewhat similiar to that of a variable reluctance high- fidelity record playing catrigde. The DC output voltages produced by additional circuitry located within the transducer case in directly proportional to the shaft rotation. The polarity of the output voltage is positive for clockwise shaft rotation, negative for counterclockwise. Another transducer element similiar in appearance and function to that shown in figure 7 converts angular movement of a shaft to an electrical signal by changing the capacitance between concentric cylinders . The inner cylinder , to which the shaft is attached, has two axial voids machined it in and rotates on precision ball bearing to assure low friction and small breakaway torque. The outer cylinder is made of insulating material with two conductive inserts which serve as capacitance plates. During rotation of the innner cylinder the defferential capacitance increases or decreases depending upon the direction of rotation. An electronic circuit located within the transducer housing convert the capacitance variation into output voltage changes proportional to shaft rotation. The transducer has greater sensitivity, lower inertia and less breakaway torque than the inductive transducer, therefore it can be used for the recording of muscle contractions of less force and amplitude than is possible with most other types of motion transducers. Fig. 8. Transducer element of fig. 7 fitted with lever and mounting bar for recording contractions of cardiac or smooth muscle. Lever arms may be attached to these transducers, by means of which they may be used to record muscle movements as in experiments on the responses of cardiac muscle. ( see fig.8 ). 3.2 Pulse transducers A transducer designed to monitor pressure changes accompanying pulsatile blood flow in extremities in shwon in fig. 9. This pressure transducer uses a piezoeleetric crystal which generates minute electrical signals when compressed. The crystal similiar to that employed is some microphones and phonograph cartridges. When this transducer is attached to a finger as in chapter 12, pulsatile pressure variations caused by arterial expansion will produce a signal output. Figure 9. Piozoeleetric transducer for recording peripheral pulse. 3.3 Temperature Transducers Temparature may be detected and Transduced using thermocouples, thermistors, bimetallic strips, etc. A device quite common bioinstrumentation is the thermistor : its resistance varies with temperature. Usually a Wheatstone –brigde circuit is used with thermistor probes to convert the resistance change into voltage variations. Thermistors are available in a wide variety of resistance rangers, and may be connected to the instrumentation system from some distance by means of a 2 wire cable. 3.4 Prerssure transducers It is often desirable to record gauge absolute or differetial presurres, such a arterial blood pressure or air pressure within a closed system. The electronic pressured transducer shown in figure 10 is used to measure and / or record direct fluid pressure in vessels or cavicities of organisms. It can also be used to measure air pressure. This instrument converts the pressure against its stainless steel diagphragm moves between two fixed capacitor plates in response to the applied pressure. The deferential capacitance changes is converted to an electrical signal by the electronic circuitry located within the transducer housing, The use of this pressure transducer is detailed in the experimental chapter dealing with blood pressure measurement. Fig. 10. Pressure transducer for use with fluid systems. Such a device is suitable for the monitoring of blood pressure via a canulla, but can be used with most all non-coorosive fluids, including air. Other transducer which may be encountered iclude those for light ( e.g. photocells), radioactivity ( e.g. Geiger-counter ), liquid drops, etc. For the subsequent experiments however, only electrodes and transducer for mechanical movement and pressure will be required. ( FROM GROUP (1).AMINUDDIN, BUYUNG, SINTHA, RIBAS, ( IKOR FK UNAIR )

Barca Mulai Berhitung dengan Skenario Bertemu Madrid

Riddick "Online" Barcelona berhasil menyusul rival abadinya, Real Madrid ke perempatfinal Champions League usai menyingkirkan AC Milan lewat agregat 4-2. Peluang El Clasico di pentas Benua Biru kini terbuka lebar. Menanggapi itu, kubu Barca tampak pede meski di dua pertemuan terakhir dipecundangi Madrid. Undian babak perempatfinal memang baru digelar pada Jumat 15 Maret 2013 mendatang. Skenario Barca akan bertemu Madrid di babak 8 besar kini mulai dibicarakan. Sebagai catatan, enam tim telah memastikan lolos ke perempatfinal. Itu setelah dini hari tadi Barcelona dan Galatasaray sukses menyusul Juventus, Borussia Dortmund, Real Madrid dan Paris Saint-Germain. Menghadapi kemungkinan El Clasico, kubu Barca tampak siap meski sebelumnya Lionel Messi dan kawan-kawan berhasil ditaklukkan Cristiano Ronaldo dan kawan-kawan di pentas Copa del Rey dan La Liga. "Pertalian ini memperlihatkan bahwa setiap lawan berbahaya. Sekarang orang membicarakan kami favorit, tapi saya tidak beranggapan seperti itu," kata pelatih sementara Barca, Jordi Roura. "Undian baru digelar Jumat nanti dan kita lihat saja nanti. Satu demi satu dulu. Tapi, jika undian harus bertemu Real Madrid maka kami akan siap. Kami akan bertarung dan mempersiapkan segalanya," lanjut Roura. Rencananya, leg 1 babak 8 besar Champions League akan digelar pada 2 dan 3 April 2013. Sedangkan leg 2 pada 9 dan 10 April 2013. (one) Berita diteruskan from http://bola.viva.co.id

Sunday, March 3, 2013

DUA LAGA EL CLASICO KEBERUNTUNGAN BERPIHAK PADA REAL MADRID

Riddick "Online Hal inilah yang patut disematkan kepada team Los blangkos Real Madrid, Ronaldo Cs sukses memetik kemenangan di dua laga klasik penuh gengsi El-Clasico antara REal Madrid dan Barcelona. Rivalitas keduanya membuat laga ini menjadi laga terpanas di dunia, baik rivalitas team maupun rivalitas kota. Laga sebelumnya copa del Rey bertempat di CAMP NOU kandang barcelona berhasil ditumbangkan REAL MADRID Dengan skor telak 3-1, 2 Gol 2 yang disumbangkan oleh Cristiano Ronaldo pada titik putih penalti dan menyambut umpan De Maria menandai kemenangan Los Blangkos pada laga itu, menjelang menit akhir Varane dengan sundulan kepala memperjauh ketertinggalan El REal setelah pada akhirnya 1 menit sebelum laga berakhir Jordi Alba Mencetak 1 gol penghibur ke gawang Diego Lopez. Hasil 3-1 untuk kemenangan Real Madrid. Bagaimana dengan pertandingan klasik Malam ini ??????? Yah, Inilah laga El-Clasico laga klasik, ,menarik, menegangkan serta membuat ratusan juta pasang mata terbelalak. Dengan perjuangan sengit Akhirnya Laga Klasik dalam lanjutan La LIGA, kembali Akhirnya Ramos CS berhasil menumbangkan rival Abadi Barcelona dengan skor tipis 2-1, Gol perdana yang dicetak Karim Benzema menyambut Umpan matang dari sisi kiri pertahanan barcelona berhasil dieksekusi dan diselesaiakan dengan baik dan berhasil menjadi Gol pada menit ke 6, Tak Mau kalah Barcelona meningkatkan tengsi serangannya, sehingga pada menit ke 14, akhirnya Sang Mesayya ( Lionel Messi ) akhirnya berhasil menyamakan kedudukan. Skor bertahan sampai turun minum babak pertama. Memasuki babak kedua antara REAL MADRID dengan BARCELONA, masing-masing team meningkatkan tengsi serangannya. Sehingga Hujan Kartu Kuning pun dianatara kedua pihak, akhirnya sebelum 15 menit babak kedua berakhir sang kapten team RAMOS akhirnya memecah kebuntuan dengan sundulan kepala yang lagsung mengarah kepada gawang Victor Valdes, menerima umpan dari tendangan sudut pemaen anyar El REAL Modrid. Madrid Menang 2-1. Bertahan hingga laga Usai, meskipun diakhir babak kedua dinyatakan berakhir oleh wasit, Protes sang kapten berbuntut kartu kuning dan akhirnya langsung diganjar kartu merah. Laga Usai REAL MENANG DUA KALI DALAM LAGA KLASIK, EL CLASICO.

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