There are a number of techniques for automatic bug detection, most of them have a high false positive rate when used in practice. This work proposes an approach, named Strip-Miner, that combines simple dependency analysis of code with a data mining technique "frequent itemset mining" to reduce the false positive rate. We adopt a two phase approach 1) finding the potential bugs and 2) filtering the false positive ones. In the first phase we extract code elements and dependencies among them using static analysis and frequent itemset mining to find programming patterns where a deviation from these patterns is considered as a potential bug. In the second phase, we use the extracted dependencies to build dependency chains between program elements in a programming pattern and a lack of such a chain potentially makes a bug false positive. Our evaluation on a set of 7 benchmarks consisting of large software code including OpenSSL, PostgreSQL, Git, FFMPEG, SQLite, Binutils and Putty shows that combining simple de- pendency analysis with pattern mining can significantly decrease the number of generated bugs. Using our approach we are able to reduce the number of generated bugs by up to 99.9% with a false positive rate of 65.19% and true positive rate of 34.18% on average as compared to an earlier frequent itemset mining based approach "PR-Miner". / Master of Science / Every software code has bugs in it that can change its expected behavior. There have been a lot of efforts to automate the process of bug detection but most of the techniques proposed have a high rate of false alarms. Some of these techniques leverage the information available in software code to extract programming patterns that can be used to find potential bugs. Although such an approach has proved to be fruitful for finding bugs but large number of false alarms makes it almost useless in software development. The elements present in a software code have relationships among them formally known as dependencies and the process of finding them is known as dependency analysis. There is a technique known as market basket analysis used by large retailers to find association between items. It works by looking for combinations of items that occur together frequently in transactions. Similarly, in a software code combinations of elements that occur together, can be used to find association between them. This technique is formally known as frequent itemset mining in the data mining domain. This work proposes an approach, named Strip- Miner, that combines dependency analysis with frequent itemset mining to reduce the rate of false alarms. We adopt a two phase approach 1)finding the potential bugs in code and 2)filtering the false alarms. In the first phase we extract code elements and dependencies among them and use frequent itemset mining to find programming patterns where a deviation from these patterns is considered as a potential bug. In the second phase, we use the extracted dependencies to build dependency chains between program elements present in a programming pattern and lack of such a chain is an indication of false alarm. Our evaluation on a set of 7 benchmarks consisting of large software code including version control systems, database management systems, software security libraries and utility software like media players shows that combining simple dependency analysis with frequent itemset mining can significantly decrease the rate of false alarms. Using our approach we are able to reduce the number of generated bugs by up to 99.9% with a false alarms rate of 65.19% and real bugs rate of 34.18% on average as compared to an earlier frequent itemset mining based approach "PR-Miner".

The invasive brown marmorated stink bug (BMSB), Halyomorpha halys (Stål), has resulted in increased use of insecticides on horticultural crops in the Mid-Atlantic US, which has diminished integrated pest management (IPM) programs that worked well otherwise. The research herein explored the use of three new tools in the development of BMSB management strategies. In one study, a BMSB pheromone lure was placed on insecticide-incorporated mesh netting to be used in an attract-and-kill strategy to protect bell peppers. The pheromone and netting deployed within a pepper field resulted in more BMSB feeding on plants within 6.1 m to the attract-and-kill screen than in further peppers or peppers in the weekly insecticide treatment. In another study, the insecticidal netting used as a row cover reduced stink bug damage to peppers, but also caused significant yield losses, possibly due to lack of light and/or pollination. The BMSB pheromone lure was also utilized in a sticky trap-based action threshold for insecticide application decisions. The trap and lure predicted densities of bugs on pepper plants and the use of an action threshold of 5 bugs per trap per week to trigger an insecticide spray reduced insecticide applications by 50% at one location, however population densities were lower at the other two locations and significance was not found among treatments. Lastly, BMSB is a nuisance pest to homeowners so we tested the exclusion efficacy of repellents on overwintering shelters and found an 8-fold reduction in BMSB that entered shelters treated with geranyl cyclopentanone (apritone). The use of BMSB pheromones paired with insecticide netting for attract-and-kill of BMSB, the development of action thresholds using captures in pheromone-baited sticky cards, and the use of apritone as a repellent are all promising IPM strategies worth refining in future studies. / MSLFS / The brown marmorated stink bug (BMSB) has become a serious household nuisance and agricultural pest in the US. BMSB feeds on and damages a large variety of crops including, fruits, vegetables, and field crops. Most growers of high value crops have increased their insecticide usage to battle this bug; thus, more sustainable integrated pest management (IPM) approaches need to be established. One main vegetable crop that BMSB damages is bell peppers. One study tested the efficacy of an attract-and-kill approach involving a BMSB pheromone lure paired with insecticide-impregnated mesh netting. When deployed in pepper fields, it was found that BMSB stayed on plants rather than receiving a lethal dose from the netting. Another study tested the netting as a row cover or as a fence between peppers and found that it did little at preventing damage. Furthermore, pepper yields were significantly lower under the row cover treatment. In another study, a clear sticky panel placed on a stake and paired with a BMSB pheromone lure was used to assist in making management decisions based on relative densities of bugs in plots. This can help determine if insecticide applications are needed. Not only is BMSB a pest of agriculture, but it is also a nuisance pest to homeowners when adults seek winter shelter during their fall dispersal period, sometimes entering homes by the thousands. The tactile repellent, geranyl cyclopentanone (apritone), was found to elicit an 8-fold reduction in the number of overwintering BMSB in overwintering shelters.

Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), an invasive agricultural pest from Asia, has established in much of the USA, where it has had significant, deleterious impacts on the production of various specialty crops. Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae) is the predominant egg parasitoid of H. halys in Asia and considered a potential agent for classical biological control. Adventive T. japonicus populations have been detected in 15 US states since 2014 and its continued spread is anticipated, creating the impetus for developing optimized sampling methods for it that are informed by its foraging ecology. Yellow sticky cards (YSC) deployed in the lower and mid-canopy of Ailanthus altissima (Mill.) Swingle trees in Virginia captured statistically equivalent numbers of T. japonicus. Season-long monitoring of T. japonicus and H. halys over two seasons resulted in significant correlations between captures of T. japonicus and H. halys adults, second instar nymphs, and all life stages combined, revealing spatiotemporal synchrony between the parasitoid and its host. Inspection of felled pheromone-baited and non-baited A. altissima showed no effect of baiting with the H. halys aggregation pheromone on H. halys egg mass abundance. Similarly, captures of T. japonicus in pheromone-baited and non-baited trees were not significantly different. Augmenting YSC with H. halys egg masses or n-tridecane did not improve T. japonicus captures. Together, these results should improve the efficiency of T. japonicus surveillance efforts and provide important guidance for future research toward enhancing the sensitivity of sampling tools for it and the interpretation of its impacts on H. halys. / Master of Science in Life Sciences / The brown marmorated stink bug (BMSB), Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), an invasive species from Asia, has become widely distributed throughout the United States as a serious pest of many important crops. Parasitic wasps that develop on eggs are often key natural enemies for reducing stink bug populations. The samurai wasp, Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae), is the primary parasitic wasp of BMSB in Asia and is under evaluation for potential use in biological control programs. Populations of samurai wasps have been detected in the United States since 2014 without intentional introduction. Its continued spread is anticipated, creating the need for effective sampling methods to track its establishment. Yellow sticky cards (YSC) deployed in the lower and mid-canopy of tree of heaven in Virginia captured similar numbers of samurai wasps. Season-long monitoring of samurai wasps and BMSB over two seasons resulted in significant correlations between captures of samurai wasps and BMSB adults, second instar nymphs, and all life stages combined, revealing spatiotemporal overlap between the wasp and its host. Inspection of felled pheromone-baited and non-baited tree of heaven showed no effect of baiting with the BMSB aggregation pheromone on numbers of BMSB egg masses. Similarly, captures of samurai wasps in pheromone-baited and non-baited trees were not significantly different. Combining YSC with BMSB egg masses or n-tridecane did not improve samurai wasp captures. Together, these results provide important guidance for future research toward enhancing the sensitivity of sampling tools for samurai wasps and the interpretation of its impacts on BMSB.

Trap crops were evaluated for harlequin bug control in broccoli field plots in 1994 and 1995. Mustard and rape prevented low densities of harlequin bug from reaching broccoli, but at high densities the insect moved from the trap plants into the broccoli. This indicates that harlequin bugs that are attracted to trap plants may damage the protected broccoli if their numbers are not prevented from increasing. Harlequin bugs were shown to have two and a partial third generation a year. Trissolcus murgantiae Ashmead and Ooencyrtus johnsoni Howard, were identified as egg parasitoids. Their combined parasitization levels for the two years were 8% and 37%. T. murgantiae accounted for 87% and 96% of the parasitization, respectively.. When 19.6 cm and 11.9 cm broccoli plants were exposed to five densities of harlequin bug adults a negative correlation between plant mortality and insect density was observed (y = 38.00 - 2.32x, r2 = 0.95 and y = 22.17 - 1.17x, r2 = 0.99, respectively). No correlation was observed in broccoli plants 11.9 tall.. Host plants affected harlequin bug development. Nymphs developed faster when reared on rape in comparison with mustard. The preoviposition time for rape reared nymphs was shorter than mustard reared insects. Fecundity and viability of eggs were not different for harlequin bugs reared at different sex ratios. / Master of Science

This study attempts to elucidate bed bug behavior in response to host cues and aggregation cues from conspecifics. Both fed and unfed bed bugs were evaluated to determine differences in behavior with regard to their circadian activities. Arena bioassays were conducted to determine the bed bug's ability to locate a host from different distances and if the antennae were essential for host location. Starved bed bugs were able to locate a host from 100 cm away. The bed bugs search path became more directed towards the host as the bed bug was placed at closer distances. The bed bugs' mean searching speed was found to be 1.7 cm/s. The bed bugs were able to locate a host even when their antennae were completely removed. Fed and unfed bed bugs were tested both individually and in groups to determine their attraction towards aggregation cues. Both fed and unfed bed bugs, regardless of sex, were significantly attracted to feces of conspecifics and exuvia of fifth instars. Finally, bed bugs were observed throughout the night to document their circadian activities after successfully taking a blood meal or failing to take a blood meal. Unfed bed bugs continued to search for a host throughout the night until aggregating together 2 hours prior to photophase. Alternatively, fed bed bugs immediately aggregated together within 30 minutes of a bloodmeal. / Master of Science in Life Sciences

The focus of this research was to evaluate commonly used insecticides and plant based scouting practices in cotton, Gossypium hirsutum (L.), prior to bloom for tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), management. As well as determine the influence of ThryvOn technology on these research objectives. Data indicate that imidacloprid may have a limited fit in non-ThryvOn cotton, while the additional mode of action afforded by ThryvOn technology could extend imidacloprid and other insecticide’s effective use prior to bloom. Additionally, sulfoxaflor and acephate remain the best products for pre-bloom management. When evaluating differences between plant based scouting methods prior to bloom used among cotton consultants across the Mid-Southern region, cotton technology and tarnished plant bug control did not cause variability in square retention monitoring methods, while sample date, or cotton growth did. However, based off these results, plant-based extension scouting recommendations do not need altering at this time.

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is an important economic pest of cotton, Gossypium hirsutum (L.), in the Midsouth region of the United States. Continuous season long infestations may result in four or more insecticide applications per growing season. However, late season applications may only be preventing minor losses when compared to overall yield. Results from this study suggest an opportunity to increase thresholds and potentially eliminate one to two insecticide applications in late bloom. Results from this experiment show no significant differences in yield when all square removal levels were simulated in the fourth and fifth week of bloom. Other factors included irrigation and cotton seed technology. Use of threshold irrigation and ThryvOn cotton resulted in greater yields than non-irrigated cotton and non-ThryvOn cotton. Information from these experiments will be used in future integrated pest management programs for more sustainable cotton production in Mississippi.

No description available.

I am working with software in academia for more than an decade and I had the "Moment" quite often. Palladio appeared just like an ordinary tool to solve my problem. Then, I changed a single parameter of my simulation---some hours later we hunted for a bug in the depths of Palladio. Based on the open source development model of Palladio and a very elegant structure of the source code, we were able to find the root cause of the problem very fast. To start fixing the problem, we "just" had to know when---in simulation time---a measurement of the SimuLizar simulator is valid. This paper summarizes our technical and philosophical discussions that ware needed to make Palladio deliver correct results and not to get lost in the depths of time and duration.

In software development projects, bug triage consists mainly of assigning bug reports to software developers or teams (depending on the project). The partial or total automation of this task would have a positive economic impact on many software projects. This thesis introduces a systematic four-step method to find some of the best configurations of several machine learning algorithms intending to solve the automatic bug assignment problem. These four steps are respectively used to select a combination of pre-processing techniques, a bug report representation, a potential feature selection technique and to tune several classifiers. The aforementioned method has been applied on three software projects: 66 066 bug reports of a proprietary project, 24 450 bug reports of Eclipse JDT and 30 358 bug reports of Mozilla Firefox. 619 configurations have been applied and compared on each of these three projects. In production, using the approach introduced in this work on the bug reports of the proprietary project would have increased the accuracy by up to 16.64 percentage points.