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This research is aim at determining the effect of styles of leadership, organization climate, and motivation of working to head of state of primary school in Central Jakarta work productivity. The method used was survey with a causal study by involving 125 respondents. There were four instruments which measured styles of leadership, organization climate, l motivation of working, and work productivity. Data has been analyzed by path-analyses. Research results revealed that: (1) there is positive and significant effect of styles of leadership to work productivity, (2) there is positive and significant effect of organization climate to work productivity, (3) there is positive and significant effect of motivation of working to work productivity, (4) there is positive and significant effect of styles of leadership to motivation of working, (5) there is positive and significant effect of organization climate to motivation of working. Therefore, it could be concluded that if head of state of primary school work productivity would be improved, then the effect of styles of leadership, organization climate, and motivation of working should be taken into consideration.

This paper presents a method for analyzing Synthetic Aperture Radar (SAR) and polarimetric SAR (PolSAR) image time series based on change detection matrices (CDM) containing information on changed and unchanged pixels. These matrices are constructed for each spatial position over the time series by implementing similarity cross tests. The proposed matrix is then exploited for adaptive temporal filtering, analysis of change dynamics and multitemporal change detection. The proposed approach is illustrated on the three following data sets: 25 ascending TerraSAR-X images and 7 descending RADARSAT 2 full polarization images over Chamonix-MontBlanc, France, where the seasonal evolution of glaciers and mountains can be observed, and a time series of 11 ascending ALOS-PALSAR dual polarization images over Merapi volcano, Indonesia during a period including the 2010 eruption. Published by Elsevier B.V. on behalf of International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS).

International audience; L-band ALOS-PALSAR images acquired before, during and after the 2010 Merapi eruption have been used to classify and map the pyroclastic deposits emplaced during this VEI-4 event. We characterize the deposits using direct-polarized and cross-polarized L-band SAR data and by combining the information of amplitude evolution with temporal decorrelation. Changes in amplitude of the radar signal enable us to map the pyroclastic density currents (PDCs) and tephra-fall deposits. Radar amplitudes in direct (HH) and cross (HV) polarizations decrease where the valley-confined and overbank block-and-ash flow (BAF) deposits (D1) are emplaced. Rainfall- and runoff-reworked PDC deposits (D2) are characterized by an increase in ground backscattering for HH polarization and a decrease for HV polarization. Ground backscattering transiently increases in both polarizations after pyroclastic surge (D3) and tephra fall (D4) deposition. We use a supervised classification method based on maximum likelihood to map the deposits D1–D4. The temporal decorrelation of the radar signal and the amplitude evolution improve the quality of classification results. Classification derived from ALOS-PALSAR images using the maximum likelihood classification provides a result with 70% classification accuracy for deposits overall. The estimated areas of valley-confined and overbank PDC deposits (either primary or reworked by rainfall and runoff) are consistent with the areas measured by other studies, while the large discrepancy in area estimated for pyroclastic-surge deposits can be partly explained by the strong erosion due to intense rainfall that removed a large part of these thin deposits.

Dans ce travail nous étudions le flanc sud du volcan Merapi (Indonésie) dévasté par la grande éruption de 2010 (IEV 4). Nous poursuivons trois objectifs : (1) Identifier les dépôts pyroclastiques et de lahars grâce à la classification «orientée-objet» appliquée à trois images GeoEye-1 (1,64 m ; 15/10/2010 et 29/07/2011) et Pléiades (0,5 m ; 29/10/2012). Ces dépôts pyroclastiques comprennent les écoulements denses canalisés, ceux qui ont débordé des vallées et les déferlantes diluées à l'amont du bassin et sur les marges des vallées. (2) Suivre l'évolution temporelle de ces dépôts grâce aux indices spectraux calculés pour chaque image. Nous avons appliqué la classification orientée-objet aux indices spectraux, NDWI, NDVI et NDRSI (Indice Normalisée du Sol Rouge). Les résultats ont permis d'identifier 15 classes de dépôts pyroclastiques, de lahars et les zones affectés dans la vallée de Gendol-Opak ( Ì´80 km²), qui représentent 75% de classes obtenues par photo-interprétation de l'image et appuyées par des observations de terrain. Les indices NDWI et NDVI ont mis en évidence les zones affectées par les déferlantes (NDWI 0,3 et NDWI

International audience; Erosion processes on active volcanoes in humid climates result in some of the highest sediment yields on Earth. Episodic sediment yields after large eruptions have been evaluated, but not the long-term and continuous patterns on persistently active volcanoes. We have used high-spatial resolution satellite imagery and DEMs/DSMs along with field-based geologic mapping to assess accurately sediment budgets for the active Semeru Volcano in Java, Indonesia. Patterns of aggradation and degradation on Semeru differ from that of other active volcanoes because (1) both episodic pyroclastic density currents (PDC) and continuous supplies of tephra generate pulses of sediment, (2) sediment is transferred via cycles of aggradation and degradation that continue for >15 years in river channels after each PDC-producing eruption, and (3) rain-triggered lahars remove much greater material than fluvial transport during long, intense rainfall events. The geomorphic response of two of Semeru’s rivers to volcanic sediment migration indicates that (1) each river experiences alternating aggradation and degradation cycles following PDC-producing eruptions and (2) spatial patterns of sediment transfer are governed by geomorphic characteristics of the river reaches. Usually high degradation in the steep source reach is followed by a long bypassing middle reach. Aggradation predominates in the depositional reaches further down valley on the ring plain. Average sediment yields (103–105 t/km2/year) at persistently active volcanoes are two to three orders of magnitude lower than sediment yields after large and infrequent eruptions, but the continuous and steady sediment transfer in rivers removes more sediment on a mid-term (10 years) to long-term (30 years) basis. In contrast to the trend observed on composite cones after large and infrequent eruptions, decay of sediment yields is not exponential and river channels do not fully recover at steadily active volcanoes as episodic inputs from BAF eruptions, superimposed on the background remobilization of daily tephra, have a greater cumulative effect.

International audience; The present work explores the object-oriented classification (OOC) of high-spatial resolution (HSR) satellite panchromatic imagery for mapping the geology of the persistently active Semeru volcano and its ring plain, east Java, Indonesia. A panchromatic SPOT5 image and a digital elevation model (DEM) have been used to identify geologic units, structures, landforms and deposits. The panchromatic image was georeferenced and enhanced using histogram equalization. The enhanced image was segmented into polygons using the EnviFx (©Exelis) Software. The polygons were delineated and classified on the basis of spectral (panchromatic hues and textures), topographic (slope, elevation) information and geologic/geomorphic processes. The validity of classification was evaluated by interpreting Google Earth images, aerial photographs and limited field observations. The classification consists of three hierarchical levels across the volcanic area of about 745 km2. The first operational spatial level includes seven large volcano domains based on the spectral content of the volcanic, tectonic and lithological structures, and principal catchments. The second operational level, based on contextual relationships (topography, drainage network, vegetation cover type, stratigraphy and slope dynamics), encompasses 20 geological units that range between 30 and 80 km2 in area. Among the units, the third operational level distinguishes as many as 47 geomorphological sub-units (0.25–25 km2) according to slope gradient, deposit type, mass-wasting process and weathering. The resulting map provides a detailed pattern of geologic and geomorphic features unlike previous geologic maps that identified only 11 stratigraphic units. We show that the high-spatial resolution panchromatic SPOT5 scene can help to safely map the geology and landforms of persistently active volcanoes such as Semeru. We have applied the OOC technique on one HSR GeoEye panchromatic image to map another active volcano, Merapi in Central Java, after considerable geomorphic changes due to the large eruption in 2010.

The paper illustrates the application of high-spatial resolution satellite images in interpreting volcanic structures and eruption impacts in the Tengger–Semeru massif in east Java, Indonesia. We use high-spatial resolution images (IKONOS and SPOT 5) and aerial photos in order to analyze the structures of Semeru volcano and map the deposits. Geological and tectonic mapping is based on two DEMs and on the interpretation of aerial photos and four SPOT and IKONOS optical satellite images acquired between 1996 and 2002. We also compared two thermal Surface Kinetic Temperature ASTER images before and after the 2002–2003 eruption in order to delineate and evaluate the impacts of the pyroclastic density currents. Semeru's principal structural features are probably due to the tectonic setting of the volcano. A structural map of the Tengger–Semeru massif shows four groups of faults orientated N40, N160, N75, and N105 to N140. Conspicuous structures, such as the SE-trending horseshoe-shaped scar on Semeru's summit cone, coincide with the N160-trending faults. The direction of minor scars on the east flank parallels the first and second groups of faults. The Semeru composite cone hosts the currently active Jonggring-Seloko vent. This is located on, and buttressed against, the Mahameru edifice at the head of a large scar that may reflect a failure plane at shallow depth. Dipping 35° towards the SE, this failure plane may correspond to a weak basal layer of weathered volcaniclastic rocks of Tertiary age. We suggest that the deformation pattern of Semeru and its large scar may be induced by flank spreading over the weak basal layer of the volcano. It is therefore necessary to consider the potential for flank and summit collapse in the future. The last major eruption took place in December 2002–January 2003, and involved emplacement of block-and-ash flows. We have used the 2003 ASTER Surface Kinetic Temperature image to map the 2002–2003 pyroclastic density current deposits. We have also compared two 10 m-pixel images acquired before and after the event to describe the extent and impact of an estimated volume of 5.45 × 106 m3 of block-and-ash flow deposits. An ash-rich pyroclastic surge escaped from one of the valley-confined block-and ash flows at 5 to 8 km distance from the crater and swept across the forest and tilled land on the SW side of the Bang River Valley. Downvalley, the temperature of the pyroclastic surge decreased and a mud-rich deposit coated the banks of the Bang River Valley. Thus, hazard mitigation at Semeru should combine: (1) continuous monitoring of the eruptive activity through an early-warning system, and (2) continuous remote sensing of the morphological changes in the drainage system due to the impact of frequent pyroclastic density currents and lahars.