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With the number of cores on a chip continuing to increase, we are moving towards an era where many-core platforms will soon be ubiquitous. Efficient use of tens to hundreds of cores on a chip and their memory resources comes with unique challenges. Some of these major challenges include: 1) Data Coherency -- the need for coherency protocol and its induced overhead poses a major obstacle for scalability of many-core platforms. 2) Memory requirement variation -- concurrently running applications on a many-core platform have variable and different memory requirements, not only across different applications, but also within a single application; in this dynamic scenario, static analysis may not suffice to capture dynamic behaviors. 3) Scalability -- inefficiency of a central management makes distributed management a necessity for many-core platforms. To address all these issues, this dissertation proposes a comprehensive approach to manage available memory resources in many-core platforms equipped with Software Programmable Memories (SPMs). The main contributions of this dissertation are: 1) We introduce SPMPool: a scalable platform for sharing Software Programmable Memories. The SPMPool approach exploits underutilized memory resources by dynamically sharing SPM resources between applications running on different cores and adapts to the overall memory requirements of multiple applications that are concurrently executing on the many-core platform. 2) We propose different central and distributed management schemes for SPMPool and study the efficiency of auction-based mechanisms in solving the memory mapping problem. We also introduce a distributed auction-based scheme to manage the memory resources of platforms without central coordination. 3) We introduce offline and online memory phase detection methods in order to increase the adaptivity of memory management to the temporal changes in memory requirements of a single application. We also use memory phasic information to relax the need for static analysis of applications.We implemented a Java and Python based simulator for many-core platforms to investigate the efficacy of the proposed methods in this dissertation.The runtime memory management schemes proposed here enable better performance, power, and scalability for many-core systems.

In the present study, the antioxidant and antimicrobial effects of essential oil (EO) and extract of Pimpinella affinis on the shelf life of rainbow trout during storage at refrigerator temperature based on three indicators of microbial, chemical and sensory quality parameters were evaluated. For this purpose, fish samples were stored in zein coatings containing 1.00% EO and 2.00% extract and in combination treatment containing 1.00% of each of them in refrigerator for 12 days. All of treatments were analyzed for microbiological count (Enterobacteriaceae, psychrophilic bacteria, mesophilic bacteria and pseudomonas bacteria) and chemical including pH, thiobarbituric acid reactive substances (TBARS), total volatile base nitrogen, peroxide value (POV) and free fatty acids (FFAs) and sensory (odor, color and texture) characteristics. Results showed that the highest levels of three factors including TBARS, POV and FFAs were related to the control sample and the least amount of these parameters was observed in EO and extract combination treatments. This effect of combined treatment was also observed in the reduction of total volatile basic nitrogen and pH parameters. Total bacterial counts during storage in fish treated with the extract and EO were remained below the acceptable level and microbial spoilage was significantly decreased compared to control. According to the sensory evaluation, treatments containing EO and extract showed improvement in this index compared to control treatment during storage. Based on the results of this study, it can be concluded that the EO and extract of P. affinis as active ingredients in zein coating successfully improve the quality and shelf life of the fish in the refrigerator.

Beef is susceptible to rapid spoilage due to its high amount of protein (18.00%) and moisture (72.00%). Food industries have recently found methods to extend beef shelf-life. The influence of beef dipping in hydro-alcoholic extract of sumac (SE) and chitosan (CH) coating incorporated with Zataria multiflora essential oil (ZEO) on microbial, chemical and sensory quality of beef was evaluated during refrigerated storage. Total viable counts (TVC), lactic acid bacteria, Pseudomonas spp., Enterobacteriaceae and yeasts-molds, total volatile nitrogen (TVN), thiobarbituric acid reactive substance values (TBARS) and peroxide value (PV) were founded to be significantly lower in all treatment groups compare to control groups during storage time. The highest level of antimicrobial effects induced by chitosan, SE 4.00% and ZEO. We found that in TVC (3.69 log CFU g-1 reduction compared with control group (sterile distilled water), Enterobacteriaceae (3.61 log CFU g-1 reduction) and lactic acid bacteria (2.67 log CFU g-1 reduction), respectively. Sumac gave a pleasant effect on sensory attributes and chitosan coating enriched with ZEO significantly improved sensory scores except for flavor factor. The results revealed the bio preservative properties of chitosan, hydro-alcoholic extract of sumac and Z. multiflora Boiss essential oil during refrigeration in normal packaging of beef.

Listeria monocytogenes is one of the major causes of infections in developing countries. In this study, chemical composition and anti-listerial effect of the essential oil of Zataria multiflora Boiss. alone and in combination with monolaurin were evaluated at different pH values (5, 6, and 7) and temperatures (5 ˚C and 30 ˚C). Chemical composition of Zataria multiflora Boiss. essential oil was evaluated by gas chromatography-mass spectrometry (GC-MS) analysis. Minimum inhibitory concentration (MIC) of the essential oil and monolaurin were determined using microbroth dilution method and the interactions of essential oil and monolaurin were determined by the evaluation of fractional inhibitory concentrations (FIC) index. Carvacrol (63.20%) and thymol (15.10%) were found as the main components of the essential oil. The MIC values of the oil and monolaurin at pH 7 and 30 ˚C were measured as 312.50 µg mL(-1) and 125.00 µg mL(-1), respectively. Combination of monolaurin and Z. multiflora essential oil were found to act synergistically (FIC index0.5) against L. monocytogenes under different pH and temperature conditions. Decrease in the pH and temperature values have increased the anti-listerial activity of monolaurin and the essential oil. The lowest MIC value of monolaurin and essential oil was observed at pH 5 and 5 ˚C. According to our results, the oil alone or in combination with monolaurin at low pH and temperature conditions showed a promising inhibitory effect on L. monocytogenes.