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ANALISIS MEDAN LISTRIK PADA PLASMA KORONA DENGAN KONFIGURASI CINCIN BIDANG

BERKALA FISIKA Vol 13, No 4 (2010): Berkala Fisika
Publisher : BERKALA FISIKA

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Abstract

It has been studied efectivity of the electric field and density of current that have been determined by the physical criteria from a long size of cylinder and a radius of thin ring from the corona plasma generator with the plane ring electrode. The result of the calculation is indicate that the strong electrics field will be resulted by the configurations of the thin ring form, contiguity apart between the thin rings (minimum cylinder length) and the size of the thin ring radius which near of the size of external cylinder radius. The radial symmetrical of geometric form of the thin ring is causing it has not current density form at tip of the thin ring.   Key words : Plasma,  plane-ring, electric field, density of current.

HUBUNGAN ANTARA POLINOMIAL JONES (ASPEK NON-PERTURBATIF) DAN VACUUM EXPECTATION VALUE DARI OPERATOR WILSON LOOP (ASPEK PERTURBATIF) DENGAN MENGGUNAKAN AKSI CHERN SIMONS WITTEN

YOUNGSTER PHYSICS JOURNAL Vol 1, No 1 (2012): Youngster Physics Journal Oktober 2012
Publisher : YOUNGSTER PHYSICS JOURNAL

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Abstract

Perturbatif aspect of Chern Simons Witten theory is viewed as value of Vacuum Expectation Value (VEV) of Wilson loop operator while non-perturbatif aspect of Chern Simons Witten theory is viewed as value of Jones Polynomial. Both aspects will be compared. Calculation of Jones Polynomial is counted by using braiding formula concept which later will be applicated to (SU)2 gauge group. VEV calculation of Wilson loop operator is counted by using Feynman’s diagram and by using vertex and propagator values. Both calculations will be counted to second order of coupling constant. The result of this research indicate that value of pertubatif aspect and non-perturbatif aspect is same although both aspects was counted by two different methods. Keyword : Chern Simons Witten, Vacuum Expectation Value, Wilson loop, Jones Polynomial.

ANALISIS PENGARUH KARAKTERISTIK WILAYAH (KELURAHAN) TERHADAP BANYAKNYA KASUS DEMAM BERDARAH DENGUE (DBD) DI KOTA SEMARANG

MEDIA STATISTIKA Vol 5, No 2 (2012): Media Statistika
Publisher : Jurusan Statistika FSM Undip

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Abstract

DBD still become one of the major problems of public health in Indonesia because the death rate tended sufferers to increase from year to year. Incredible happening (KLB) of DBD which was initially occurring every five years, now it’s getting often happens. In the city of Semarang, during 2009 occurring 165 times KLB in urban village, 35 times KLB in the level of community health centers and 15 times KLB at the district level. Though the number of DBD cases in 2009 from 2008 was declining, but in this year also noted that the number of deaths resulting from DBD increased to 43 people from 18 people in 2008. This research aims to analyze the characteristics of the neighborhood (whose data is always updated by BPS via PODES) that affect the number of cases of DBD (whose data is always updated by DKK) in Semarang city, by creating the best regression models using stepwise technique. Regression model analysis of results obtained best is Y = 23.029 + 0.004 X1 – 0.074 X2 + 0.070X3, where Y is IR/10000 PDDK, that is the number of residents affected by DBD for each 10000 inhabitants, X1 is the number of residents aged 15-24 years, X2 is total area of land of rice fields and X3 is area of land for buildings and grounds around the page. Keywords: DBD, Characteristics of the Neighborhood, Regression, Stepwise

Perhitungan Medan Listrik dan Rapat Arus pada Plasma Lucutan Korona dengan Konfigurasi Jarum–Cincin

SAINS DAN MATEMATIKA Volume 22 Nomor 1 Tahun 2014
Publisher : SAINS DAN MATEMATIKA

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Abstract

This paper presents analytical method for the calculations of the electric field and current density in needle-ring configurations of the corona discharge plasma. The needle is considered hyperboloidal. The result of the calculation indicates that the strong electric field generated by the sharp needle due to the unsymmetrical of geometric form of it. Similarly, the current density at the tip of the sharp needle is higher than at the ring. The value of the electric field and current density depends on geometric form, especially radius of the hyperbola, radius of the ring, and the distance between the electrodes. Radius of the hyperbola must be smaller than radius of the ring.   Keywords : electric field, current density, needle-ring configurations, geometric form

Perhitungan Medan Listrik dan Rapat Arus pada Plasma Lucutan Korona dengan Konfigurasi Jarum–Cincin

JURNAL SAINS DAN MATEMATIKA Volume 22 Issue 1 Year 2014
Publisher : JURNAL SAINS DAN MATEMATIKA

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Abstract

This paper presents analytical method for the calculations of the electric field and current density in needle-ring configurations of the corona discharge plasma. The needle is considered hyperboloidal. The result of the calculation indicates that the strong electric field generated by the sharp needle due to the unsymmetrical of geometric form of it. Similarly, the current density at the tip of the sharp needle is higher than at the ring. The value of the electric field and current density depends on geometric form, especially radius of the hyperbola, radius of the ring, and the distance between the electrodes. Radius of the hyperbola must be smaller than radius of the ring.   Keywords : electric field, current density, needle-ring configurations, geometric form

GENERATOR PEMBANGKIT PLASMA DENGAN KONFIGURASI ELEKTRODA BATANG TIPIS DAN JARUM

BERKALA FISIKA 2015: Berkala Fisika Vol. 18 No. 2 Tahun 2015
Publisher : BERKALA FISIKA

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Abstract

The application of plasma generator has been developed for everyday live because it can generate high electric field and induced current, even by only 12 volt of potential difference. The advantages of the plasma generator are mainly caused by configuration form of its electrodes which is usually very sharp and asymmetric form. In this paper, plasma generator has been discussed using electrodes configuration of the thin rod and needle in two dimensional planes. The result shows that the plasma generator can produce various high electric fields, which highest field at the tip of needle electrode. In case of configuration of needle electrode, it will be produced saturated current due to their asymmetric electrodes, while in case of thin rod electrode; it will be no saturated current due to symmetric electrode. Keywords: plasma generator, thin rod and needle configuration electrodes, electric field, saturated current.

Mesh-Assisted Laser-Induced Plasma Spectroscopy Using Pulse Carbon Dioxide Laser for Analysis of Powder Material by Confining the Powder in a Hole and Employing a Condensation Technique

Indonesian Journal of Chemistry Article in press
Publisher : Universitas Gadjah Mada

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Abstract

Analysis of impurity in powder samples has been made by using metal-assisted laser-induced plasma spectroscopy utilizing a pulsed CO2 laser. Various powders including food powder, supplement powder, baby powder, and medicine powder were employed as sample materials. Experimentally, the powder sample was tightly put in a hole made on a metal plate and a metal mesh was placed on the powder surface. A pulse CO2 laser (10.6 μm, 1500 mJ) was irradiated on the powder surface passing through the metal mesh. Luminous plasma was induced by mesh just above the mesh when a part of laser energy attacked the mesh. The other part of laser energy impinged the powders and ablated fine particles of powder to the plasma to be atomized and excited. Identification and analysis of elements in powder were successfully conducted. A linear calibration curve of Cu in baby powder has been demonstrated with an intercept zero, certifying that the present technique was a high possibility to be employed for semi-quantitative analysis of elements in powder material. It was proved that by applying the present technique and employing a condensation technique, the detection sensitivity of Cr impurity in the powder sample increased about twenty times compared to the case without condensation. The limit of detection of Cr in rice powder sample was 25 mg/kg. The proposed method was very convenient for the identification and analysis of elements in the powder sample.