The fragility of planetary systems

We specify the range to which perturbations penetrate a planetesimal system. Such perturbations can originate from massive planets or from encounters with other stars. The latter can have an origin in the star cluster in which the planetary system was born, or from random encounters once the planetary system has escaped its parental cluster. The probability of a random encounter, either in a star cluster or in the Galactic field depends on the local stellar density, the velocity dispersion and the time spend in that environment. By adopting order of magnitude estimates we argue that the majority of planetary systems born in open clusters will have a {\em Parking zone}, in which planetesimals are affected by encounters in their parental star cluster but remain unperturbed after the star has left the cluster. Objects found in this range of semi-major axis and eccentricity preserve the memory of the encounter that last affected their orbits, and they can therefore be used to reconstruct this encounter. Planetary systems born in a denser environment, such as in a globular cluster are unlikely to have a Parking zone. We further argue that some planetary systems may have a {\em Frozen zone}, in which orbits are not affected either by the more inner massive planets or by external influences. Objects discovered in this zone will have preserved information about their formation in their orbital parameters.Comment: 4 pages, accepted for publication in MNRA

Optical injection and terahertz detection of the macroscopic Berry curvature

We propose an experimental scheme to probe the Berry curvature of solids. Our method is sensitive to arbitrary regions of the Brillouin zone, and employs only basic optical and terahertz techniques to yield a background free signal. Using semiconductor quantum wells as a prototypical system, we discuss how to inject Berry curvature macroscopically, and probe it in a way that provides information about the underlying microscopic Berry curvature.Comment: 4 pages, accepted in Physical Review Letter

Large area silicon sheet by EFG

The development of a technique for the production of silicon ribbon is discussed. Extensive characterization of the multiple ribbon Furnace 3A main zone temperature profile was performed and the information used to improve uniformity of heating. Irregularities in the main zone heater were associated with growth difficulties at specific cartridge locations, and growth conditions subsequently improved by profiling the main zone heater. Good growth conditions were established in all three cartridge positions. These improvements allowed multiple growth of three 10 cm wide ribbons to be demonstrated for periods of an hour on several occasions. A gas distribution system for the 10 cm cartridge was introduced and demonstrated to lead to improved ambient control during growth. Growth without and with CO2 showed that quality improvement in 10 cm ribbon grown with cold shoes results from ambient manipulation

Remote Sensing/gis Integration for Site Planning and Resource Management

The development of an interactive/batch gridded information system (array of cells georeferenced to USGS quad sheets) and interfacing application programs (e.g., hydrologic models) is discussed. This system allows non-programer users to request any data set(s) stored in the data base by inputing any random polygon's (watershed, political zone) boundary points. The data base information contained within this polygon can be used to produce maps, statistics, and define model parameters for the area. Present/proposed conditions for the area may be compared by inputing future usage (land cover, soils, slope, etc.). This system, known as the Hydrologic Analysis Program (HAP), is especially effective in the real time analysis of proposed land cover changes on runoff hydrographs and graphics/statistics resource inventories of random study area/watersheds

The Application of Geographic Information System for Sustainable Land Use Planning of Central Kalimantan Province, Indonesia

Lands are scarce resources and must be optimally and sustainably utilize to satisfy the growing world population. Not all lands are suitable for agriculture purposes and this can be achieved through agroecological approach with the aid of Geographic Information System. A land use planning study on the basis of agroecological zoning was conducted in Central Kalimantan province of Indonesia.  The general methodology in this study was based on land evaluation concept.  The expert system called Land Use Program was employed to support land evaluation as general guideline for selection of agriculture system and land utilization. Land resources and climate data were then interpreted by expert system to determine zoning system for forest, perennial and annual crop, and agroforestry.  The application of geographic information (GIS) was used as database management system (DBMS) for tabular and spatial reference data as basic information of land use planning.  On the basis of land characteristics and climatic data, Central Kalimantan would be geographically divided into 7 main zones and 4 sub-zones with its zoning system within each zone or sub-zone.  The Zone I, VI, VII, and sub-zone V.2 with the total area of 4,481,300 hectares or 29.1% of total Central Kalimantan province would be allocated for forest.  The Zone II and sub-zone V.1 would be recommended for perennial crop, while zone IV (sub-zone IV1 and IV.2) would be allocated for annual crops. The total area for the perennial crop zones (II and V.1) and annual crop zones (VI) would be 6,708,400 hectares (43.6%) and 2,564,000 hectares (16.7%), respectively.  The Zone III with an area of almost 1,509,000 hectares (9.8%) would be recommended for agroforestry.  The agroecological zone approach allows efficient, effective, and optimal land utilization but for must be cautiously applied to ensure sustainable future development of Central Kalimantan. Keywords: GIS, land use planning, agroecological system, Central Kalimantan

On the Application of Zone Flooding in a Traffic Warning System

The LIWAS Traffic Warning System aims at providing early warning to vehicles about slippery conditions on the road. The LIWAS system is currently under development and consists of two main parts: sensors for measuring and classifying the state of the road, and a communication infrastructure for distributing road-state information to vehicles. This paper concentrates on the communication infrastructure, and considers the application of zone flooding for implementing the distribution of road-state information. Zone flooding combines flooding and geocasting to distribute road-state information in a geographically bounded area. To evaluate the applicability of zone flooding in the LIWAS system, a simulation model has been created using the Network Simulator 2. The simulation model captures a representative road-scenario and has been used to evaluate several flooding protocols when used to implement zone flooding. The primary evaluationcriteria are the load on the network and the capability to warn other vehicles in time