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Bandung, Indonesia

The Bandung Institute of Technology or Institute of Technology, Bandung is a state, coeducational research university located in Bandung, Indonesia. Established in 1920, ITB is the oldest technology-oriented university in Indonesia.ITB was considered the top choice among Indonesia's high school students in 2006 and has been credited as one of the most "prestigious" universities in Indonesia, together with University of Indonesia, and Gadjah Mada University.Sukarno, the first president of the Republic of Indonesia, earned his engineering degree in civil engineering from ITB. B. J. Habibie, the third president of Indonesia also graduated from ITB.The university cultivates professional and social activities by supporting its students' unions, the student government councils that exist in every department. Each students' union has its own distinctly designed jacket that, among other traditions, serves as part of its member identity. There are also a number of student activity units/clubs supporting ITB student interests in rounding out their educational experience. It is not uncommon that the students and alumni are identified by the clubs to which they belong at ITB, in addition to their class year and major.The university is a member of LAOTSE, an international network of leading universities in Europe and Asia exchanging students and senior scholars.Until 2012, ITB had four study programs internationally accredited from an independent U.S. accrediting institution, ABET, where ITB is the only public university in Indonesia, with this particular international accrediting institution. The four study programs are Ocean Engineering, Electrical Engineering, Chemical Engineering, and Engineering Physics.ITB's march "Mars ITB" and hymn "Hymne ITB" were arranged by a former professor, Prof. Dr. Sudjoko Danoesoebrata. Wikipedia.

Suwarno,Bandung Institute of Technology
Gaodianya Jishu/High Voltage Engineering

Partial discharge(PD) is one of the most important phenomenon in high voltage insulations. In most cases, the appearance of partial discharges is related to insulation defects. Understanding partial discharges is important for diagnosis on insulation condition. Corona discharges appear when extremely high electric field appears on the conductor surface exceeding the electric field strength of the gas. The high electric field may occur at around protrusion with very sharp tip. This paper reported a holistic approach of corona discharge investigation. The needle-plane electrode system was used. The medium between the electrodes was air. The needle was made from steel with radius of curvature of 3 μm (Ogura needle). Sinusoidal as well as triangular applied voltages were used. The waveform of the corona discharges was measured using a digital oscilloscope. The corona discharge pulses were measured using a phase-resolved PD measurement system. The system was able to measure the magnitude (q) and phase angle position (φ) of each PD pulses, as well as the number of discharge pulses (n). The role of applied voltage was investigated using phase-resolved analysis of corona discharge pulses through pulse sequence, pulse magnitude and pulse number analysis. Experimental results indicated that corona discharge current waveform was an impulse with rise time of about several ns and the impulse width of about 100 ns. The Fast Fourier Transform analysis indicated that the corona discharge current waveform had several spectrum peaks at frequency of 7.8 MHz, 85.9 MHz, 109.4 MHz and 195.3 MHz. The experimental results also showed that discharge pulses were concentrated around the peak of applied voltage for both sinusoidal and triangular voltages. The discharge magnitude, as well as its probability of occurrence, was strongly dependent on the instantaneous applied voltage. The shape of φ-n, as well as φ-q-n PD patterns, were strongly reflected by the shape of applied voltage. In order to get deep understanding of the corona discharge, by utilizing results of the phase-resolved analysis, electrical equivalent circuits of corona discharges were proposed. The electrical equivalent circuit contained capacitances and a spark gap. For deeply understanding of PD phenomenon, computer simulation was done by using the proposed electrical equivalent circuits. The similarity of the measured and simulated PD patterns was assessed by comparing measured and simulated the φ-q-n and φ-n PD patterns. The results indicated that simulated PD patterns similar to those obtained from experiment. Source

Indarto A.,Bandung Institute of Technology
Research on Chemical Intermediates

The photolysis of nitrous acid (HONO) is an important reaction of atmospheric chemistry due to the fact that it can be the source of OH radical in the troposphere. Despite its role as a radical precursor, the chemical mechanisms leading to HONO formation are not well understood. It is commonly assumed that HONO formation is due to both homogeneous and heterogeneous processes involving NO x (mixture of NO and NO 2) in which the kinetic and mechanistic details are still under investigation. In this discussion, we would like to highlight the formation of HONO from NO 2 and nitric acid (HNO 3) in the presence of organic particulate. We understood that in the real case, many parameters can influence the reaction mechanism; however, this is just an effort to have a better understanding of the study of HONO formation in the atmospheric process. © Springer Science+Business Media B.V. 2011. Source

Singleton D.,California State University, Fresno | Singleton D.,Bandung Institute of Technology | Vagenas E.C.,Academy of Athens
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

We discuss two possible covariant generalizations of the Aharonov-Bohm effect - one expression in terms of the space-time line integral of the four-vector potential and the other expression in terms of the space-time "area" integral of the electric and magnetic fields written in terms of the Faraday 2-form. These expressions allow one to calculate the Aharonov-Bohm effect for time-dependent situations. In particular, we use these expressions to study the case of an infinite solenoid with a time varying flux and find that the phase shift is zero due to a cancellation of the Aharonov-Bohm phase shift with a phase shift coming from the Lorentz force associated with the electric field, E=-∂tA, outside the solenoid. This result may already have been confirmed experimentally. © 2013 Elsevier B.V. Source

Wijaya D.D.,Bandung Institute of Technology
Journal of Geodesy

This paper presents a fast and accurate algorithm for high-frequency trans-ionospheric path length determination. The algorithm is merely based on the solution of the Eikonal equation that is solved using the conformal theory of refraction. The main advantages of the algorithm are summarized as follows. First, the algorithm can determine the optical path length without iteratively adjusting both elevation and azimuth angles and, hence, the computational time can be reduced. Second, for the same elevation and azimuth angles, the algorithm can simultaneously determine the phase and group of both ordinary and extra-ordinary optical path lengths for different frequencies. Results from numerical simulations show that the computational time required by the proposed algorithm to accurately determine 8 different optical path lengths is almost 17 times faster than that required by a 3D ionospheric ray-tracing algorithm. It is found that the computational time to determine multiple optical path lengths is the same with that for determining a single optical path length. It is also found that the proposed algorithm is capable of determining the optical path lengths with millimeter level of accuracies, if the magnitude of the squared ratio of the plasma frequency to the transmitted frequency is less than (Formula presented.), and hence the proposed algorithm is applicable for geodetic applications. © 2015 Springer-Verlag Berlin Heidelberg Source

This study will discuss the extent to which a locally initiated metropolitan governance institution under Indonesia's decentralization reform has helped to deal with the problems of inter-local government development, using the Kartamantul (Yogyakarta Metropolitan Region) as a case study. It will also draw some lessons learned from the practice of metropolitan governance in the region.The Kartamantul joint secretariat has been found effective in coordinating and managing solid waste and waste water infrastructure development. Several key success factors in the Kartamantul joint secretariat includes: First, collective horizontal decision-making process; second, the transparence and openness in the negotiation process among the local government involved, in which they may have different and often conflicting interests; third, the leaderships and shared vision of all heads of the local governments in the region; and fourth, the heads of the involved local governments share the common vision that urban infrastructure development should be implemented in a synergistic way in order to provide better quality public service. © 2009 Elsevier Ltd. Source

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