Long term monitoring of trichloroethylene degradation indicator parameters using sensors

Past operations at Savannah River Site (SRS) have resulted in significant amount of groundwater contamination with trichloroethylene. Natural attenuation of chlorinated solvents via reductive dechlorination is one of the most important processes occurring at SRS, which requires monitoring. Many traditional monitoring techniques require manual sampling and analysis at an onsite or offsite laboratory, which is costly and time consuming. Therefore the need for a system, which can accurately and cost-effectively conduct real-time analysis using automated sensors, is important. There are several characteristics of groundwater like pH, ORP, conductivity and chloride that may be monitored to assess the TCE degradation. To evaluate the effectiveness of the sensors to measure the required parameters, a series of tests were conducted by varying the parameters that can affect the performance of the sensors. Interference by the other ions is neither strong nor permanent but can cause interference during measurement. So a thorough testing of the ISE is necessary to obtain reliable data

Thermocline Circulation Driven at Surface Outcrops of Isopycnal Surfaces

Potential vorticity (PV) defined as: q = Δθ .(fk + Ω) where θ is density anomaly, Ω (Δ x u) is relative vorticity, k is unit vertical vector and f the coriolis parameter, is used as a dynamical tracer to study the interior thermocline circulation. Using the generalized flux form of PV equation (Haynes and McIntyre, 1987), wind stress and buoyancy fluxes at surface outcrops of isopycnal surface are translated into PV fluxes. The PV flux condition so derived considers seasonal movement of the isopycnal outcrops and geostrophic turbulence. A constant layer depth model, forced by the above flux condition, is used to study its influence on the interior circulation. The impermeability theorem of Haynes and McIntyre (1987), justifies treatment of a single isopycnic layer in isolation. Non-linear, quasi-geostrophic equations are used to study the dynamics on a rectangular basin model. The model is forced by PV at the northern boundary of the domain, which represents the location where the PV flux enters the thermocline interior. PV input at the northern boundary allows the circulation to build up until opposite PV input at some other boundaries limits the process. The model simulation shows active northern, eastern and western boundary layers, and an interior circulation pattern with properties similar to those inferred by the homogenization theory of Rhines and Young (1982a). However, in the present study, the boundary layers control the key features of the circulation unlike in the classical models driven by Ekman pumping. The results show that the anticyclonic gyre forming in response to negative PV input on the northern boundary, has a strength depending on the intensity of the forcing, lateral diffusivity and the eastern boundary condition. In the case of an upwelled isopycnal (free slip eastern wall), the eastern boundary layer is stable and penetrates to a considerable distance south. On the contrary, for isopycnal intersecting the eastern boundary (no-slip wall), the eastern boundary layer separates at a short distance from the northeast corner, injecting massive amounts of positive vorticity into the basin. Cyclonic eddies are shed at a constant frequency near the eastern boundary, in the no-slip case, propagate towards the west and dissipate near the western boundary. Experiments with realistic subduction rates show that the PV transport due to the total pressure gradient along the isopycnal outcrop dwarfs the transport due to subduction. The results obtained mimic to a certain extent features of subtropical gyre circulation near eastern boundaries, notably in the Azores frontal area

Integrated Biometric Template Security using Random Rectangular Hashing

Large centralized biometric databases, accessible over networks in real time are especially used for identification purposes. Multimodal biometric systems which are more robust and accurate in human identification require multiple templates storage of the same user analogous to individual biometric sources. This may raises concern about their usage and security when these stored templates are compromised since each person is believed to have a unique biometric trait. Unlike passwords, the biometric templates cannot be revoked and switch to another set of uncompromised identifiers when compromised. Therefore, fool-proof techniques satisfying the requirements of diversity, revocability, security and performance are required to protect stored templates such that both the security of the application and the users2019; privacy are not compromised by the impostor attacks. Thus, this paper proposes a template protection scheme coined as random rectangular hashing to strengthen the multimodal biometric system. The performance of the proposed template protection scheme is measured using the fingerprint FVC2004 and PolyU palmprint database

Effect of pH and temperature on the carbonate promoted dissolution of sodium meta-autunite

Release of uranium from Na-autunite, an artificial mineral created as a result of polyphosphate injection in the subsurface at the DOE Hanford Site, takes place during slow dissolution of the mineral structure. Stability information of the uranyl-phosphate phases is limited to conditions involving pH, temperature, and a few aqueous organic materials. The carbonate ion, which creates very strong complexes with uranium, is the predominant ion in the groundwater composition. The polyphosphate technology with the formation of autunite was identified as the most feasible remediation strategy to sequester uranium in contaminated groundwater and soil in situ. The objectives of the experimental work were (i) to quantify the effect of bicarbonate on the stability of synthetic sodium meta-autunite created as a result of uranium stabilization through polyphosphate injection, (ii) calculate the kinetic rate law parameters of the uranium release from Na-autunite during dissolution, and (iii) to compare the process parameters with those obtained for natural calcium meta-autunite. Experiments were conducted using SPTF apparatus, which consists of syringe pumps for controlling flow rate, Teflon reactors and a heating/cooling system. 0.25 grams of synthetic Na-autunite was placed in the reactor and buffer solutions with varying bicarbonate concentrations (0.0005 to 0.003 M) at different pH (6 - 11) were pumped through the reactors. Experiments were conducted at four different temperatures in the range of 5 - 60oC. It was concluded that the rate of release of uranium from synthetic Na-autunite is directly correlated to the bicarbonate concentration. The rate of release of uranium increased from 1.90 x 10-12 at pH 6 to 2.64 x 10-10 (mol m-2 s-1) at pH 11 at 23oC over the bicarbonate concentration range tested. The activation energy values were invariant with the change in the bicarbonate concentration; however, pH is shown to influence the activation energy values. Uranyl hydroxides and uranyl carbonates complexes helped accelerate the dissolution of autunite mineral

Development of a Generic Expert System for Entomological Applications

Computing and Information Science

CIMGEN: Controlled Image Manipulation by Finetuning Pretrained Generative Models on Limited Data

Content creation and image editing can benefit from flexible user controls. A common intermediate representation for conditional image generation is a semantic map, that has information of objects present in the image. When compared to raw RGB pixels, the modification of semantic map is much easier. One can take a semantic map and easily modify the map to selectively insert, remove, or replace objects in the map. The method proposed in this paper takes in the modified semantic map and alter the original image in accordance to the modified map. The method leverages traditional pre-trained image-to-image translation GANs, such as CycleGAN or Pix2Pix GAN, that are fine-tuned on a limited dataset of reference images associated with the semantic maps. We discuss the qualitative and quantitative performance of our technique to illustrate its capacity and possible applications in the fields of image forgery and image editing. We also demonstrate the effectiveness of the proposed image forgery technique in thwarting the numerous deep learning-based image forensic techniques, highlighting the urgent need to develop robust and generalizable image forensic tools in the fight against the spread of fake media

Head repositioning errors in normal student volunteers: a possible tool to assess the neck's neuromuscular system

BACKGROUND: A challenge for practitioners using spinal manipulation is identifying when an intervention is required. It has been recognized that joint pain can interfere with the ability to position body parts accurately and that the recent history of muscle contraction can play a part in that interference. In this study, we tested whether repositioning errors could be induced in a normal population by contraction or shortening of the neck muscles. METHODS: In the experimental protocol, volunteers free of neck problems first found a comfortable neutral head posture with eyes closed. They deconditioned their cervical muscles by moving their heads 5 times in either flexion/extension or lateral flexion and then attempted to return to the same starting position. Two conditioning sequences were interspersed within the task: hold the head in an extended or laterally flexed position for 10 seconds; or hold a 70% maximum voluntary contraction in the same position for 10 seconds. A computer-interfaced electrogoniometer was used to measure head position while a force transducer coupled to an auditory alarm signaled the force of isometric contraction. The difference between the initial and final head orientation was calculated in 3 orthogonal planes. Analysis of variance (1-way ANOVA) with a blocking factor (participants) was used to detect differences in proprioceptive error among the conditioning sequences while controlling for variation between participants. RESULTS: Forty-eight chiropractic students participated: 36 males and 12 females, aged 28.2 ± 4.8 yrs. During the neck extension test, actively contracting the posterior neck muscles evoked an undershoot of the target position by 2.1° (p <0.001). No differences in repositioning were found during the lateral flexion test. CONCLUSION: The results suggest that the recent history of cervical paraspinal muscle contraction can influence head repositioning in flexion/extension. To our knowledge this is the first time that muscle mechanical history has been shown to influence proprioceptive accuracy in the necks of humans. This finding may be used to elucidate the mechanism behind repositioning errors seen in people with neck pain and could guide development of a clinical test for involvement of paraspinal muscles in cervical pain and dysfunction

Amount of health care and self-care following a randomized clinical trial comparing flexion-distraction with exercise program for chronic low back pain

BACKGROUND: Previous clinical trials have assessed the percentage of participants who utilized further health care after a period of conservative care for low back pain, however no chiropractic clinical trial has determined the total amount of care during this time and any differences based on assigned treatment group. The objective of this clinical trial follow-up was to assess if there was a difference in the total number of office visits for low back pain over one year after a four week clinical trial of either a form of physical therapy (Exercise Program) or a form of chiropractic care (Flexion Distraction) for chronic low back pain. METHODS: In this randomized clinical trial follow up study, 195 participants were followed for one year after a four-week period of either a form of chiropractic care (FD) or a form of physical therapy (EP). Weekly structured telephone interview questions regarded visitation of various health care practitioners and the practice of self-care for low back pain. RESULTS: Participants in the physical therapy group demonstrated on average significantly more visits to any health care provider and to a general practitioner during the year after trial care (p < 0.05). No group differences were noted in the number of visits to a chiropractor or physical therapist. Self-care was initiated by nearly every participant in both groups. CONCLUSION: During a one-year follow-up, participants previously randomized to physical therapy attended significantly more health care visits than those participants who received chiropractic care