Indonesian Institute of Sciences

About: Indonesian Institute of Sciences is a facility organization based out in Jakarta, Indonesia. It is known for research contribution in the topics: Population & Genus. The organization has 4795 authors who have published 10544 publications receiving 76990 citations. The organization is also known as: Indonesian Institute of Sciences Cibinong, Indonesia.

Probing the Effects of Strong Electromagnetic Fields with Charge-Dependent Directed Flow in Pb-Pb Collisions at the LHC

Abstract: The first measurement at the LHC of charge-dependent directed flow (v1) relative to the spectator plane is presented for Pb-Pb collisions at √sNN p = 5.02 TeV. Results are reported for charged hadrons and D0 mesons for the transverse momentum intervals pT > 0.2 GeV=c and 3 < pT < 6 GeV=c in the 5%–40% and 10%–40% centrality classes, respectively. The difference between the positively and negatively charged hadron v1 has a positive slope as a function of pseudorapidity η, dΔv1=dη = [1.68 ± 0.49(stat) x 0.41(syst) × 10^−4. The same measurement for D^0 and D¯ ^0 mesons yields a positive value dΔv1/dη = [4.9 ± 1.7(stat) ± 0.6(syst) × 10^−1, which is about 3 orders of magnitude larger than the one of the charged hadrons. These measurements can provide new insights into the effects of the strong electromagnetic field and the initial tilt of matter created in noncentral heavy ion collisions on th e dynamics of light (u, d, and s) and heavy (c) quarks. The large difference between the observed Δv1 of charged hadrons and D0 mesons may reflect different sensitivity of the charm and light quarks to the early time dynamics of a heavy ion collision. These observations challenge some recent theoretical calculations, which predicted a negative and an order of magnitude smaller value of dΔv1=dη for both light flavor and charmed hadrons.

Urban Lakes in Megacity Jakarta: Risk and Management Plan for Future Sustainability

Abstract: The impact of urban development in the distinct surrounding inhabited areas on urban lakes in megacity Jakarta has been so pervasive that makes the lakes very vulnerable to environmental disturbances. High levels of disturbances to the urban lakes from urban development in the past and recent years, such as lake filling, land use change, shoreline encroachment, and garbage dump, have caused nearly 10 - 20% of urban lakes loss in megacity Jakarta. The consistency of lakes loss has been estimated from the old-Dutch map to the recent year maps indicating that the lakes continuously have been sacrificed for urban area development. In addition to the lake front destruction, siltation and the excessive macrophyte coverage have caused more than 25% of existing lakes shrinkage in area and volume and based on the lake morphology assessment, nearly 50% of lakes have been damaged. The lakes inurban village, rural village, agricultural and urban village – industrial areas are at high risk of lakefront landscape destruction, siltation/sedimentation, eutrophication and water pollution, including pathogenic bacteria and toxic pollutants contamination that can pose threat on human's health as results of untreated sewage inflow and storm water runoff to the lakes. The complexity of the problems faced by urban lakes in Jakarta requires a comprehensive management plan that is not only effective in maintaining the stability of lake ecosystem but also effective in improving urban life, such as socio-culture-economic conditions of people around the lakes. Fundamental requirement is that the urban lake should be managed according to its surrounding characteristics and conditions, and functional context.

Discharge estimation from H-ADCP measurements in a tidal river subject to sidewall effects and a mobile bed

Abstract: Horizontal acoustic Doppler current profilers (H-ADCPs) can be employed to estimate river discharge based on water level measurements and flow velocity array data across a river transect. A new method is presented that accounts for the dip in velocity near the water surface, which is caused by sidewall effects that decrease with the width to depth ratio of a channel. A boundary layer model is introduced to convert single-depth velocity data from the H-ADCP to specific discharge. The parameters of the model include the local roughness length and a dip correction factor, which accounts for the sidewall effects. A regression model is employed to translate specific discharge to total discharge. The method was tested in the River Mahakam, representing a large river of complex bathymetry, where part of the flow is intrinsically three-dimensional and discharge rates exceed 8000 m3 s-1. Results from five moving boat ADCP campaigns covering separate semidiurnal tidal cycles are presented, three of which are used for calibration purposes, whereas the remaining two served for validation of the method. The dip correction factor showed a significant correlation with distance to the wall and bears a strong relation to secondary currents. The sidewall effects appeared to remain relatively constant throughout the tidal cycles under study. Bed roughness length is estimated at periods of maximum velocity, showing more variation at subtidal than at intratidal time scales. Intratidal variations were particularly obvious during bidirectional flow conditions, which occurred only during conditions of low river discharge. The new method was shown to outperform the widely used index velocity method by systematically reducing the relative error in the discharge estimates