Hop Harvest Timing

In the Northeast, hop harvest generally begins in mid-August and continues through mid-September. Harvest date is primarily dependent on the hop variety but weather can delay or hasten maturation and impact when harvest will occur. In addition to weather, various pests, such as spider mites and downy mildew, can similarly impact harvest timing. The time at which you harvest hops can affect the various qualities of your finished product. Alpha and beta acid content peaks before many essential oils have fully developed. Delaying harvest can provide time for these oils to develop but increases the amount of time the hops are left vulnerable to disease and fall rains which can result in degradation of resins

Techniques to evaluate the importance of common cause degradation on reliability and safety of nuclear weapons.

As the nuclear weapon stockpile ages, there is increased concern about common degradation ultimately leading to common cause failure of multiple weapons that could significantly impact reliability or safety. Current acceptable limits for the reliability and safety of a weapon are based on upper limits on the probability of failure of an individual item, assuming that failures among items are independent. We expanded the current acceptable limits to apply to situations with common cause failure. Then, we developed a simple screening process to quickly assess the importance of observed common degradation for both reliability and safety to determine if further action is necessary. The screening process conservatively assumes that common degradation is common cause failure. For a population with between 100 and 5000 items we applied the screening process and conclude the following. In general, for a reliability requirement specified in the Military Characteristics (MCs) for a specific weapon system, common degradation is of concern if more than 100(1-x)% of the weapons are susceptible to common degradation, where x is the required reliability expressed as a fraction. Common degradation is of concern for the safety of a weapon subsystem if more than 0.1% of the population is susceptible to common degradation. Common degradation is of concern for the safety of a weapon component or overall weapon system if two or more components/weapons in the population are susceptible to degradation. Finally, we developed a technique for detailed evaluation of common degradation leading to common cause failure for situations that are determined to be of concern using the screening process. The detailed evaluation requires that best estimates of common cause and independent failure probabilities be produced. Using these techniques, observed common degradation can be evaluated for effects on reliability and safety

Beneficial Exclusion Experiment

There are over 400 acres of hops currently in production within the Northeast with many new growers coming onto the scene. While hop production in the Northeast continues to rebound, many farmers are looking for additional information and clarity on how pests can impact their crop production. Compared to the Pacific Northwest and other hop growing regions around the world, we do not currently have a clear understanding of the role and impact that beneficial insects have within our hop yards. It is particularly important to quantify the benefit that natural enemies provide in order to help determine economic and action thresholds for hop pests

Hop Germplasm Study

Until now, commercial hop (Humulus lupulus L.) production has not occurred in the northeast (NE) region of the United States for 150 years. Vermont production peaked in 1860 when the state produced 289,690 kg of dried hops (Kennedy 1860). A combination of the spread of hop downy mildew, the expansion of production in western states, and prohibition laws from the 1920’s contributed to the decline of the 19th century NE hop industry. Today, the Pacific Northwest states of Washington, Oregon, and Idaho remain the dominant hop production sites of the U.S. However, hop production in non-traditional regions is growing and now accounts for over 2% of the total U.S. hop acreage (George, A., 2014). Nationally, there has been recent and unprecedented growth in the craft beer sector which has dramatically increased demand for local hop production

Hop Crowning Trial Final Report

Downy mildew has been identified as the primary pathogen plaguing our northeastern hop yards. This disease causes reduced yield, poor hop quality, and can cause the plant to die in severe cases. Control measures that reduce disease infection and spread while minimizing the impact on the environment, are desperately needed for the region. Mechanical control is one means to reduce downy mildew pressure in hop yards. Scratching, pruning, or crowning is a practice initiated in the early spring either before or at the time that new growth has just emerged from the soil

Hemp Flower Harvest Date

In the Northeast, hemp harvest can take place any time from late August through October or later depending on hemp varieties and weather conditions. Harvest for autoflowering varieties can somewhat reliably be determined with the use of recommended harvest dates for individual varieties whereas full term or photoperiod sensitive varieties more often require careful monitoring through the use of visual or aromatic cues. Primarily harvest date for flower crops is determined by a number of noticeable changes in the physical characteristics of trichomes, bracts, and pistils. The trichomes, known as capitate-stalked resin glands, will begin to form as stalked structures capped with a bulbous head (similar to a small mushroom) on flower surfaces. Depending on growth operation, these glands will also begin to turn opaque and eventually amber before degradation. Other flower components such as the bracts of each individual flower will begin to swell, similar to as if flowers were pollenated, and pistils of each flower will begin to turn brown. Once approximately 90% of those pistils have begun browning, in conjunction with these other visual cues, we generally begin to harvest plants

Hemp Greenhouse Seed Treatment Evaluation

Hemp is a non-psychoactive variety of cannabis sativa L. The crop is one of historical importance in the U.S. and reemerging in worldwide importance as manufacturers seek hemp as a renewable and sustainable resource for a wide variety of consumer and industrial products. The fiber has high tensile strength and can be used to create a variety of goods. Hemp fiber consists of two types: bast and hurd. The bast fiber are the long fibers found in the bark of hemp stalks and are best suited for plastic bio-composites for vehicles, textiles, rope, insulation, and paper. The hurd fiber are short fibers found in the core of the stem and are suited for building materials, such as hempcrete and particle boards, bedding materials, and absorbents

3D Human Motion Tracking and Pose Estimation using Probabilistic Activity Models

This thesis presents work on generative approaches to human motion tracking and pose estimation where a geometric model of the human body is used for comparison with observations. The existing generative tracking literature can be quite clearly divided between two groups. First, approaches that attempt to solve a difficult high-dimensional inference problem in the body model’s full or ambient pose space, recovering freeform or unknown activity. Second, approaches that restrict inference to a low-dimensional latent embedding of the full pose space, recovering activity for which training data is available or known activity. Significant advances have been made in each of these subgroups. Given sufficiently rich multiocular observations and plentiful computational resources, highdimensional approaches have been proven to track fast and complex unknown activities robustly. Conversely, low-dimensional approaches have been able to support monocular tracking and to significantly reduce computational costs for the recovery of known activity. However, their competing advantages have – although complementary – remained disjoint. The central aim of this thesis is to combine low- and high-dimensional generative tracking techniques to benefit from the best of both approaches. First, a simple generative tracking approach is proposed for tracking known activities in a latent pose space using only monocular or binocular observations. A hidden Markov model (HMM) is used to provide dynamics and constrain a particle-based search for poses. The ability of the HMM to classify as well as synthesise poses means that the approach naturally extends to the modelling of a number of different known activities in a single joint-activity latent space. Second, an additional low-dimensional approach is introduced to permit transitions between segmented known activity training data by allowing particles to move between activity manifolds. Both low-dimensional approaches are then fairly and efficiently combined with a simultaneous high-dimensional generative tracking task in the ambient pose space. This combination allows for the recovery of sequences containing multiple known and unknown human activities at an appropriate (dynamic) computational cost. Finally, a rich hierarchical embedding of the ambient pose space is investigated. This representation allows inference to progress from a single full-body or global non-linear latent pose space, through a number of gradually smaller part-based latent models, to the full ambient pose space. By preserving long-range correlations present in training data, the positions of occluded limbs can be inferred during tracking. Alternatively, by breaking the implied coordination between part-based models novel activity combinations, or composite activity, may be recovered

Shear strength theories for beams of variable depth

Flexibly formed reinforced concrete beams usually have varying cross sections along their longitudinal axis, capitalising on the fluidity of concrete to create optimised geometries. According to Orr et al. [1], these new shapes have led to challenges for shear design, especially when the depth of the beams is relatively small. It is crucial to be able to accurately determine the shear strength of such beams to maintain structural safety whilst achieving material optimisation.The effective shear force method is adopted for tapering beams in many design codes. Recent work by Paglietti et al. [2] has highlighted concerns over the use of such an approach. In this paper, the theoretical basis for stress distributions in tapered beams built by Timoshenko [3] and Oden [4] in their elastic range is reviewed and then extended to included cracked behaviour.It is found that the effective shear force method used in design codes does not accurately account for the stress distribution in a section both in elastic and cracked stage of concrete, underestimating the peak shear stress for beams with inclined soffits. This is important for flexibly formed beams, and has implications for designersAs a result of this work, a new calculation and design method for shear reinforcement is proposed.Keywords: variable depth beam, shear strength, shear stress distribution, flexible formwork.The authors acknowledge and are grateful for the support of the BRE CICM (www.bath.ac.uk/bre), the University of Bath, and the China Scholarship Council who collectively fund the PhD position that has resulted in this work