CFA2: a Context-Free Approach to Control-Flow Analysis

In a functional language, the dominant control-flow mechanism is function call and return. Most higher-order flow analyses, including k-CFA, do not handle call and return well: they remember only a bounded number of pending calls because they approximate programs with control-flow graphs. Call/return mismatch introduces precision-degrading spurious control-flow paths and increases the analysis time. We describe CFA2, the first flow analysis with precise call/return matching in the presence of higher-order functions and tail calls. We formulate CFA2 as an abstract interpretation of programs in continuation-passing style and describe a sound and complete summarization algorithm for our abstract semantics. A preliminary evaluation shows that CFA2 gives more accurate data-flow information than 0CFA and 1CFA.Comment: LMCS 7 (2:3) 201

Effect of ionizing radiation on the properties of PLA packaging materials

Poly(lactic acid) (PLA) is attractive as a substitute for classical polymer packaging material due to its biodegradability and sufficient mechanical and barrier properties. Presented research was focused on the changes of basic mechanical parameters after ionizing irradiation performed with doses in the range of 2.5–25 kGy, commonly used in radiation sterilization and preservation of foods. Two commercial available PLA packaging films were tested. The influence of radiation dose on the mechanical properties – tensile strength and elongation were determined using standardized methods. Radiation resistance of PLA is sufficient for packaging applications. The investigations of gas products of radiolysis of PLA have been made by gas chromatography after electron beam (EB) irradiations

Impact of ionizing radiation on the properties of a hydrobiodegradable aliphatic - aromatic copolyester

This paper presents the results of the studies on changes of selected quality parameters of hydrobiodegradable aliphatic-aromatic copolyester (AAC). Radiation treatment was performed at the Institute of Nuclear Chemistry and Technology in Warsaw, using cobalt gamma-ray sources "Issledovatel" (dose rate 0.389 Gy/h) and "GC 5000" (8.5 Gy/h). The material was subjected to the impact of radiation doses of 5, 10, 20 and 40 kGy. Selected parameters of the packaging material, important from the standpoint of a potential application, have been studied: gaseous products of radiolysis, strength parameters in accordance with PN EN ISO 527-3, global migration PN-EN-1186-1:2002, FT-IR analysis using PCA method, contact angle measurement using the drop shape method. The results have demonstrated that there is no significant influence of ionizing radiation on AAC film parameters. Correlation between doses applied and values of measurements has not been found