Investigating Construct Validity of the Cyber--Peer Experiences Questionnaire

With electronic technology becoming increasingly important in all aspects of modern life, traditional forms of relating with others have crossed into the cyber realm. Within that context, both positive and negative aspects of relational behavior have advanced in ways still largely underexplored in the research literature. One such area, termed “cyberaggression,” has recently gained momentum as a research focus. Given the numerous mental health sequelae from being involved in cyberaggression, such as anxiety, depression, and suicidal ideation, there is a clear and compelling need for more research in this area. To date, however, there remains little consensus on the conceptualization and measurement of cyberaggression; in the absence of sound instrumentation for the construct, substantive investigations in this domain are hindered. Therefore, the primary purpose of this research study was to explore construct validity for the Cyber – Peer Experiences Questionnaire (C-PEQ), a promising new measure that assesses experiences of cyberaggression and cybervictimization via electronic communication. Confirmatory factor analysis of the data did not provide support for the hypothesized two-factor model solution of the instrument (MLM 2=433.79, RMSEA = .06, CFl = .88, SRMR = .06). However, the C-PEQ displayed evidence for internal consistency reliability (C-PEQ: α = .88; cyberaggression subscale: α = .75; cybervictimization subscale: α = .84). Evidence for convergent validity with theoretically similar constructs was mixed. Specific areas of model misspecification as well as suggestions for future research are discussed

Exploring Construct Validity and Measurement Invariance of the Cyberbullying Experiences Survey

Given recent calls for advancing valid instrumentation in the field of cyberaggression, the present study evaluated construct validity and measurement invariance for the Cyberbullying Experiences Survey (CES) in a high school and college student sample. A series of confirmatory factor analyses (CFA), reliability analyses, and a nomological net evaluation were conducted to address these aims. The data did not provide support for the hypothesized four-factor model for cyberaggression or cybervictimization (i.e., unwanted contact, malice, deception, and public humiliation). Upon implementing suggested and theoretically supported modification indices, support for a four-factor solution for both cyberaggression and cybervictimization was provided. To subsequently evaluate measurement invariance, single-group CFAs were constructed to test invariance of the four-factor structure across college and high school students. Results provided support for the four-factor model solution of cyberaggression and cybervictimization in the college sample but not in the high school sample. Two cyberaggression subscales (i.e., unwanted contact and deception) correlated at r = .99, indicating the potential for multicollinearity, and incremental fit indices for the cybervictimization model solution did not meet recommended cut-off values in the high school sample. Revised model results based on statistical and theoretical considerations evaluated a restructured three-factor solution for cyberaggression (i.e., “sexual,” “direct,” and “coercion”) and cybervictimization (i.e., “sexual,” “direct,” and “defamation”). Fit indices provided initial support for the revised model solution for both CES cyberaggression items (College: MLM c2 (163) = 273.01, RMSEA = .04, CFI = .92, SRMR = .06; High School: MLM c2 (165) = 196.29, RMSEA = .03, CFI = .96, SRMR = .08) and cybervictimization items (College: MLM c2 (163) = 367.81, RMSEA = .05, CFI = .93, SRMR = .06; High School: MLM c2 (160) = 256.32, RMSEA = .06, CFI = .92, SRMR = .07). Utilizing the revised factor solution for the remaining analyses, the CES displayed evidence for internal consistency reliability across college (cyberaggression items: α = .83; cybervictimization items: α = .89) and high school (cyberaggression items: α = .88; cybervictimization items: α = .90), although internal consistencies for the CES cyberaggression subscales ranged from poor to good (α = .54 - .88) and acceptable to excellent (α = .76 - .92) for the CES cybervictimization subscales across both college and high school samples. Evidence for convergent validity with theoretically similar constructs was mixed. Specific areas of model misspecification as well as directions for future cyberaggression measurement research and policy are discussed

Procedural Content Generation: Using A.I. to Generate Playable Content

This thesis is about using Artificial Intelligence in regards to Procedural Content Generation to help try and avoid a deadlock scenario in a hypothetical dungeon exploring game. The deadlock scenario is essentially having a key being placed in a room that’s inaccessible to the player. An example of such a scenario would be if the key to room A being in Room B, the key to room B was in room A, and the player was in room C. The program generates the dungeon world with a random number of rooms inside it, each room also having a random number of generated sub-rooms or no sub-rooms at all, and then will place the rooms’ respective keys somewhere in the world, so long as whatever arrangement occurs in the end will allow the player to explore the entire dungeon world if they desire or need to. The entire program was written in Java, and the dungeon world’s rooms are arranged into a tree data structure to represent each room’s relationship to one another

Maize Water Use in Living Mulch Systems with Stover Removal

Constraints to maize (Zea mays L.) stover biomass harvest may be mitigated by using a living mulch (LM) to offset C exports and control soil erosion. Living mulches can compete with the main crop for resources, particularly water. The objectives of this research were to quantify soil water dynamics and maize water use in continuous maize with stover removal. Continuous soil water content (SWC) and reproductive whole-plant water use were measured in no-till maize growing in LMs of creeping red fescue (CF) (Festuca rubra L.), Kentucky bluegrass (KB) (Poa pratensis L.), and a no-LM control between 2008 and 2010 near Ames, IA. In 2 yr with excessive rainfall (2008 and 2010), LMs increased SWC compared to the control at 15 cm. No-till LM treatments lowered grain yield in 2008 and 2010 compared to the control, although a KB fall strip-till treatment, which was part of the larger research study, produced yields that were not different than the control all 3 yr. Reproductive water use efficiency for no-till KB in 2008 and 2009 (51 and 42 g grain per cm water) was 21 and 14% greater than the control (42 and 37) but 24% lower in 2010 (41 vs. 51). Maize water use in the control exhibited a bimodal response averaged across the 3 yr with peak water use occurring at the R1 through R2 period (0.58 cm d−1) and declining to 0.26 cm d−1 during R5 through R6. In contrast, no-till KB exhibited a simple negative linear relationship with water use rates declining from a high of 0.47 cm d−1 during the R1 through R2 period to 0.22 cm d−1 during R5 through R6. These results indicate LMs may increase SWC and utilize water more effectively, particularly when combining strip-till and herbicide management

Evaluation of Grass and Legume Species as Perennial Ground Covers in Corn Production

Corn (Zea mays L.) stover has been identified as an important feedstock for biofuel production but its removal will likely increase soil erosion. To address this issue 35 species of grasses and legumes were evaluated as potential perennial ground covers (PGCs) in corn. Selection of species encompassed both C3 and C4 species with a wide range of developmental and morphological features. The objectives were to (i) identify species that could support a high level of corn production while requiring minimal management and (ii) identify morphological traits and growth habits of suitable entries as PGC. Over the 3-yr study period species with slow growing and spreading habits were more conducive to corn production, even though these PGCs still caused an average 23% reduction in corn grain yield. Meadow fescue (Festuca pratensis Huds.), sheep fescue (Festuca ovina L.), Canada bluegrass (Poa compressa L.), fowl bluegrass (Poa palustris L.), and colonial bentgrass (Agrostis capillaris L.) were identified as suitable PGC species. These species were generally shorter and slower to spread into the corn rows compared with other, more aggressive species. Based on these observations an ideotype for future PGC species should be low growing, clump forming, and shade tolerant and have delayed green-up in the spring

Mission Produce

Mission Produce\u27s founding, growth and expansion into oversea\u27s markets is discussed. In particular, Mission Produce\u27s ripening centers are presented as an innovation in avocado marketing

Costes de los sesgos de detección en el monitoreo de poblaciones basado en índices

Managers of wildlife populations commonly rely on indirect, count–based measures of the population in making decisions regarding conservation, harvest, or control. The main appeal in the use of such counts is their low material expense compared to methods that directly measure the population. However, their correct use rests on the rarely–tested but often–assumed premise that they proportionately reflect population size, i.e., that they constitute a population index. This study investigates forest management for the endangered Red–cockaded Woodpecker (Picoides borealis) and the Wood Thrush (Hylocichla mustelina) at the Piedmont National Wildlife Refuge in central Georgia, U.S.A. Optimal decision policies for a joint species objective were derived for two alternative models of Wood Thrush population dynamics. Policies were simulated under scenarios of unbiasedness, consistent negative bias, and habitat–dependent negative bias in observed Wood Thrush densities. Differences in simulation outcomes between biased and unbiased detection scenarios indicated the expected loss in resource objectives (here, forest habitat and birds) through decision–making based on biased population counts. Given the models and objective function used in our analysis, expected losses were as great as 11%, a degree of loss perhaps not trivial for applications such as endangered species management. Our analysis demonstrates that costs of uncertainty about the relationship between the population and its observation can be measured in units of the resource, costs which may offset apparent savings achieved by collecting uncorrected population counts.Los gestores de poblaciones de fauna silvestre a menudo toman decisiones relativas a la conservación, recolección o control a partir de medidas indirectas de la población basadas en recuentos. El principal atractivo que presenta este tipo de recuentos son los bajos costes de material, en comparación con otros métodos que miden la población de forma directa. Sin embargo, el correcto uso de los mismos depende de una premisa que suele darse por sentada, aunque rara vez se comprueba, y que consiste en suponer que reflejan proporcionalmente el tamaño de la población; es decir, que constituyen un índice poblacional. El presente estudio investiga la gestión forestal de dos especies en peligro de extinción: el pájaro carpintero de cresta roja (Picoides borealis) y el zorzal mustelino (Hylocichla mustelina) en la Reserva Nacional de Animales Salvajes de Piedmont, en Georgia central, Estados Unidos. Se simularon varias políticas de conservación bajo escenarios referentes a las densidades del zorzal mustelino insesgados, con un consistente sesgo negativo y con un sesgo negativo dependiente del hábitat. Las diferencias obtenidas con respecto a los resultados de simulación entre los escenarios de detección sesgados y los no sesgados indicaron la pérdida prevista en los objetivos en materia de recursos (en este caso, el hábitat y las aves del bosque) a través de una toma de decisiones basada en los recuentos poblacionales sesgados. Teniendo en cuenta los modelos y la función de los objetivos que hemos empleado en nuestro análisis, las pérdidas previstas ascendieron al 11%, lo que supone un porcentaje bastante significativo en aplicaciones tales como la gestión de especies en peligro de extinción. Nuestro análisis demuestra que los costes de incertidumbre acerca de la relación entre la población y su observación pueden medirse en unidades del recurso dado; es posible que estos costes compensen los ahorros aparentemente conseguidos mediante la recopilación de recuentos poblacionales no corregidos

Remote Control Aircraft

The purpose of the RC aircraft design was not to address a problem that has not been solved, but to redesign an aircraft with the intent to understand the practical applications of the building process. Our approach to completing this project involved two phases; the planning phase and the building phase. In the planning phase, we made selections for the airfoil, wing, fuselage, tail, elevators, and ailerons. These choices were made using aeronautical engineering concepts and theory. For the building phase, we focused on materials selection, fabrication, and testing. During our design process, a lot of time went to choosing the airfoil. While researching, we considered three governing factors: drag coefficient, lift coefficient, and manufacturability. Each airfoil offered a variation of these parameters.The Eppler 423 airfoil was picked for its low drag coefficient. There were issues during fabrication. These issues mainly stemmed from the lack of quality equipment. For example, initial attempts to cut the balsa wood into the airfoil profile caused wood splitting. This happened because the saw was too coarse for that grain of wood. If this project were redone, we would utilize tools that are commonly used within the hobbyist community to optimize fabrication. Our project focused on the application of the engineering design process that we have become familiar with as undergraduate students. In terms of purpose, our project would identify most with the R/C aircraft hobbyist community and FSAE community that also engineer and build aircrafts for personal or competition uses.https://scholarscompass.vcu.edu/capstone/1137/thumbnail.jp

Living Mulch for Sustainable Maize Stover Biomass Harvest

The Renewable Fuels Standard mandate provides enhanced opportunity for maize (Zea mays L.) stover use as a bioenergy feedstock. Living mulch (LM) offers a possible solution for the natural resources constraints associated with maize stover biomass harvest. A two site-year study was conducted near Boone and Kanawha, IA, in both maize following maize (MM) and maize following soybean [Glycine max (L.) Merr.] (SM) sequences to evaluate the impact of established and chemically suppressed Kentucky bluegrass (Poa pratensis L.) (KB) ‘Ridgeline’, ‘Wild Horse’, ‘Oasis’, and ‘Mallard’ blend and creeping red fescue (Festuca rubra L.) (CF) ‘Boreal’ as LM on three maize hybrids (population sensitive, population insensitive, and yield stable). Maize grain yield for the no LM treatments in the MM and SM sequences was 12.0 and 13.2 Mg ha-1, respectively, at Boone and 12.8 and 14.8 Mg ha-1, respectively, at Kanawha, 23-73% greater than the LM treatment. Ethanol yield (L ha-1) was 12-119% greater, protein concentration was ≤9% greater, and starch concentration was ≤1% lower in the no LM treatment maize than LM treatment maize. Maize hybrid by cover interaction was significant for parameters including total aboveground biomass and protein concentration at Boone, with inconsistent maize hybrid responses to the LM system. Stover yield, stover quality, stover C and N, leaf area index (LAI), maize plant density, maize maturity, and sequence year in the MM sequence were also evaluated. Results emphasize the need for maize hybrid and LM system compatibility and effective LM suppression techniques