The ARGO-YBJ Experiment Progresses and Future Extension

Gamma ray source detection above 30TeV is an encouraging approach for finding galactic cosmic ray origins. All sky survey for gamma ray sources using wide field of view detector is essential for population accumulation for various types of sources above 100GeV. To target the goals, the ARGO-YBJ experiment has been established. Significant progresses have been made in the experiment. A large air shower detector array in an area of 1km2 is proposed to boost the sensitivity. Hybrid detection with multi-techniques will allow a good discrimination between different types of primary particles, including photons and protons, thus enable an energy spectrum measurement for individual specie. Fluorescence light detector array will extend the spectrum measurement above 100PeV where the second knee is located. An energy scale determined by balloon experiments at 10TeV will be propagated to ultra high energy cosmic ray experiments

ARGO-YBJ constraints on very high energy emission from GRBs

The ARGO-YBJ (Astrophysical Radiation Ground-based Observatory at YangBaJing) experiment is designed for very high energy $\gamma$-astronomy and cosmic ray researches. Due to the full coverage of a large area ($5600 m^2$) with resistive plate chambers at a very high altitude (4300 m a.s.l.), the ARGO-YBJ detector is used to search for transient phenomena, such as Gamma-ray bursts (GRBs). Because the ARGO-YBJ detector has a large field of view ($\sim$2 sr) and is operated with a high duty cycle ($>$90%), it is well suited for GRB surveying and can be operated in searches for high energy GRBs following alarms set by satellite-borne observations at lower energies. In this paper, the sensitivity of the ARGO-YBJ detector for GRB detection is estimated. Upper limits to fluence with 99% confidence level for 26 GRBs inside the field of view from June 2006 to January 2009 are set in the two energy ranges 10$-$100 GeV and 10 GeV$-$1 TeV.Comment: accepted for publication in Astroparticle Physic

A generic analytical target cascading optimization system for decentralized supply chain configuration over supply chain grid

While centralized supply chain configuration (SCC) adopts an integrated decision model solved by an all-in-one decision method, decentralized SCC normally allows constituent enterprises to employ distributed decision models which are coordinated through a decomposition method to achieve an overall solution. Decentralized SCC paradigm could offer various contemporary advantages such as individual suppliers' decision right protection and overall decision efficiency enhancement. This paper proposes an optimization system, atcPortal, to practically enable such a decentralized SCC process. Individual suppliers convert their local decision support systems into decision web services to form a distributed open-standard SCC service platform, called supply chain grid (SCG) in this paper. As a decomposition-based optimization method, analytical target cascading (ATC) is the mechanism for atcPortal to coordinate these web services through three phases of service searching, service-based ATC problem definition, and service-oriented ATC execution. atcPortal is a generic and extensible web portal in the sense that ATC accommodates a variety of decentralized SCC decision structures without confining the local decision models of individual enterprises. Finally, the usage of atcPortal is demonstrated through a typical decentralized SCC problem.Analytical target cascading Supply chain configuration Decentralized decision making Web service