Orbital experiment capsule feasibility study. Volume I - Summary Final report
Feasibility estimate, mission profile, and design Orbital Experiment Capsule /OEC/ Mars satellite to be used in Voyager Project
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Results for “Feasibility Study”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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A feasibility study of an adaptive binary detector
Feasibility of system acting as adaptive binary detector
Bruce, M. M.↗
Feasibility study of silicon nitride regenerators
The feasibility of silicon nitride as a regenerator matrix material for applications requiring inlet temperatures above 1000 C is examined. The present generation oxide ceramics are used as a reference to examine silicon nitride from a material characteristics, manufacturing, thermal stress and aerothermodynamic viewpoint.
Fucinari, C. A.↗
Failure Modes and Effects Analysis (FMEA) Assistant Tool Feasibility Study
An effort to determine the feasibility of a software tool to assist in Failure Modes and Effects Analysis (FMEA) has been completed. This new and unique approach to FMEA uses model based systems engineering concepts to recommend failure modes, causes, and effects to the user after they have made several selections from pick lists about a component s functions and inputs/outputs. Recommendations are made based on a library using common failure modes identified over the course of several major human spaceflight programs. However, the tool could be adapted for use in a wide range of applications from NASA to the energy industry.
Flores, Melissa↗
Feasibility study for a secondary Na/S battery
The feasibility of a moderate temperature Na battery was studied. This battery is to operate at a temperature in the range of 100-150 C. Two kinds of cathode were investigated: (1) a soluble S cathode consisting of a solution of Na2Sn in an organic solvent and (2) an insoluble S cathode consisting of a transition metal dichalcogenide in contact with a Na(+)ion conducting electrolyte. Four amide solvents, dimethyl acetamide, diethyl acetamide, N-methyl acetamide and acetamide, were investigated as possible solvents for the soluble S cathode. Results of stability and electrochemical studies using these solvents are presented. The dialkyl substituted amides were found to be superior. Although the alcohol 1,3-cyclohexanediol was found to be stable in the presence of Na2Sn at 130 C, its Na2Sn solutions did not appear to have suitable electrochemical properties.
Abraham, K. M.↗
SU-G-IeP4-14: Prostate Brachytherapy Activity Measurement and Source Localization by Using a Dual Photon Emission Computed Tomography System: A Feasibility Study
Purpose: To monitor the activity distribution and needle position during and after implantation in operating rooms. Methods: Simulation studies were conducted to assess the feasibility of measurement activity distribution and seed localization using the DuPECT system. The system consists of a LaBr3-based probe and planar detection heads, a collimation system, and a coincidence circuit. The two heads can be manipulated independently. Simplified Yb-169 brachytherapy seeds were used. A water-filled cylindrical phantom with a 40-mm diameter and 40-mm length was used to model a simplified prostate of the Asian man. Two simplified seeds were placed at a radial distance of 10 mm and tangential distance of 10 mm from the center of the phantom. The probe head was arranged perpendicular to the planar head. Results of various imaging durations were analyzed and the accuracy of the seed localization was assessed by calculating the centroid of the seed. Results: The reconstructed images indicate that the DuPECT can measure the activity distribution and locate the seeds dwelt in different positions intraoperatively. The calculated centroid on average turned out to be accurate within the pixel size of 0.5 mm. The two sources were identified when the duration is longer than 15 s. The sensitivity measured in water was merely 0.07 cps/MBq. Conclusion: Preliminary results show that the measurement of the activity distribution and seed localization are feasible using the DuPECT system intraoperatively. It indicates the DuPECT system has potential to be an approach for dose-distribution-validation. The efficacy of acvtivity distribution measurement and source localization using the DuPECT system will evaluated in more realistic phantom studies (e.g., various attenuation materials and greater number of seeds) in the future investigation.
60 APPLIED LIFE SCIENCES↗
White Earth Biomass/Biogas Feasibility Study
The White Earth Nation examined the feasibility of cost savings and fossil energy reduction through the installation of biogas/biomass boiler at the tribal casino. The study rejected biogas options due to availability and site constraints, but found a favorable environment for technical and financial feasibility of installing a 5 MMBtu hot water boiler system to offset 60-70 percent of current fuel oil and propane usage.
09 BIOMASS FUELS↗
SU-E-T-185: Feasibility Study of Dose Rate Modulated Arc Therapy (DrMAT) for Lung SBRT
Purpose: To show the feasibility of clinical application of DrMAT for SBRT in lung cancer patients. DrMAT is a form of dynamic conformal arc therapy where MLC segments and dose rates are controlled through simple field weight optimization. Methods: To show feasibility a new treatment plan was created based on the CT of SBRT lung cancer patients. Static plans with 33 fields are made, which have 11deg in between each field and are acquired rotating gantry angle from 180deg to 188deg in CCW direction, total 352deg is rotated. MLC maintained static aperture for each field. To optimize 33 individual fields, field weight was adjusted accordingly using weight optimization algorithm. Keeping weights and MU of static plan, static MLC aperture was converted to multiple arc segments. Arc plan could be created with the fields in the intervals of 11deg. Static MLC should be converted to arc segment MLC. Dynamic conformal arc therapy plan consists of 33 arc fields, is converted to one dose rate modulated arc therapy (DrMAT) plan. DrMAT plan consists of 166 control points which becomes a single arc plan that changes the shape of MLC for every 2.2deg. The resulting DrMAT plan is not an inverse plan it is a simple form of dynamic conformal arc plan using field weight obtained from static plan. This is compared and evaluated with the VMAT plan. Results: DrMAT and VMAT plans have been compared based on the RTOG1021. Both DrMAT and VMAT plans satisfy 100% irradiation to 95% of PTV and critical organs did not exceed dose limit suggested in RTOG1021. DrMAT plan is almost similar with VMAT plan in Result. Conclusion: Field weight optimization method did not show better Resultcompared to VMAT optimization. However, considering simplicity, DrMAT satisfies the condition in RTOG1021. Therefore clinical application of DrMAT is feasible.
60 APPLIED LIFE SCIENCES↗
SU-F-T-662: Feasibility Study of Fe3O4/TaOx Nano Particles as a Radiosensitizer for Radiation Therapy
Purpose: To investigate the feasibility of using multifunctional Fe{sub 3}O{sub 4}/TaOx(core / shell) nano particles developed for CT and MRI contrast agent as dose enhancing radiosensitizers. Methods: Firstly, to verify the imaging detectability of Fe{sub 3}O{sub 4}/TaOx nano particles, in-vivo tests were conducted. Approximately 600 mg/kg of 19 nm diameter Fe{sub 3}O{sub 4}/TaOx nano particles dispersed in phosphate buffered saline(PBS) were injected to ten nude Balb/c mice through the tail vein. Difference between pre- and post-injection images was analyzed by computing the pixel histogram and correlation coefficient factor using MATLAB in the user defined ROI. Secondly, to quantify the potential therapeutic enhancement with nano materials, DER (Dose Enhancement Ratio) and number of SER (Secondary Electron Ratio) were computed using TOPAS(ver.2.0 P-03) MC simulation. Results: In CT, MRI imaging, the aorta, the blood vessel, and the liver were clearly visualized after intravenous injection of Fe{sub 3}O{sub 4}/TaOx nano particles. There was large different between pre and post-injection images of Histogram data and Coefficients of correlation factor in CT and MR are 0.006, 0.060, respectively. When 70 MeV protons were irradiated for a Gold, Tantalum, TaOx, Fe{sub 3}O{sub 4}/TaOx, Fe{sub 3}O{sub 4} nano particle, DER was 2.59, 2.41, 1.68, 1.54 and 1.36 respectively. Similarly, SER increment was 2.31, 2.15, 1.56, 1.46, and 1.27 for Gold, Tantalum, TaOx, Fe{sub 3}O{sub 4}/TaOx, Fe{sub 3}O{sub 4} nano particle, respectively. Conclusion: Fe{sub 3}O{sub 4}/TaOx nano particles have potential as a multifunctional agent which enhances the accuracy in cancer detection through visualization of developed tumor lesion and increases the therapeutic effect in proton therapy. The dose enhancement with Fe{sub 3}O{sub 4}/TaOx was estimated as half of the Gold. However, tumor targeting such as combined with magnetic field may overcome the low DER. This research was supported by the NRF funded by the Ministry of Science, ICT & Future Planning (2012M3A9B6055201 and 2012R1A1A2042414), Samsung Medical Center grant[GFO1130081].
60 APPLIED LIFE SCIENCES↗
Feasibility study on the thorium fueled boiling water breeder reactor
The feasibility of (Th,U)O 2 fueled, boiling water breeder reactor based on conventional BWR technology has been studied. In order to determine the potential use of water cooled thorium reactor as a competitive breeder, this study evaluated criticality, breeding and void reactivity coefficient in response to changes made in MFR and fissile enrichments. The result of the study shows that while using light water as moderator, low moderator to fuel volume ratio (MFR=0.5), it was possible to breed fissile fuel in negative void reactivity condition. However the burnup value was lower than the value of the current LWR. On the other hand, heavy water cooled reactor shows relatively wider feasible breeding region, which lead into possibility of designing a core having better neutronic and economic performance than light water with negative void reactivity coefficient. (authors)
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
Telerobotic field geologist - Preliminary results of a feasibility study
Results of three laboratory studies conducted to explore the feasibility of developing a telerobot to perform planetary field geology are presented. A total of 72 college students attempted to match each of 15 geologic rock samples viewed either directly or on a TV screen with its matched pair contained in a matrix of 24 rocks which they viewed directly. The first study showed that rocks viewed on TV could be matched at levels well above chance, but significantly less than by direct view. Performance under remote view was improved by adding color and by magnifying the TV image. The second study showed a large decrease in performance when viewing a miniature LCK monitor as compared to a 19-in. CRT monitor of higher resolution. In the third study performance using the 2.9-in. LCK monitor showed only insignificant increases when images were presented in 3D view or when the rock was moved. It is suggested that it is feasible to conduct geologic observations with telerobots, and the critical role that image quality plays in determining performance is demonstrated.
Cole, Robert E.↗
Feasibility study for long lifetime helium dewar
A feasible concept for a launchable three year lifetime helium dewar was investigted. Current helium dewar designs were examined to see where the largest potential reductions in parasitic heat loads can be made. The study was also devoted to examining support concepts. The support concept chosen, a passive orbital disconnect strut (PODS), has an orbital support conductance that is lower by more than an order of magnitude over current tension band supports. This lower support conductance cuts the total dewar weight in half for the same three year life time requirements. Effort was also concentrated on efficient wire feed through designs and vapor cooling of the multilayer insulation, supports, wire feed throughs and plumbing penetrations. A single stage helium dewar vs. dual stage dewars with a guard cryogen of nitrogen or neon was examined. The single stage dewar concept was selected. Different support concepts were analyzed from which the PODS support concepts was chosen. A preliminary design of the dewar was thermally and structurally analyzed and laid out including system weights, thermal performance and performance sensitivities.
Parmley, R. T.↗
MR-guided Periarterial Ethanol Injection for Renal Sympathetic Denervation: A Feasibility Study in Pigs
Purpose. To evaluate the feasibility and efficacy of image-guided periarterial ethanol injection as an alternative to transluminal radiofrequency ablation. Methods. Unilateral renal periarterial ethanol injection was performed under general anesthesia in 6 pigs with the contralateral kidney serving as control. All interventions were performed in an open 1.0 T MRI system under real-time multiplanar guidance. The injected volume was 5 ml (95 % ethanol labelled marked MR contrast medium) in 2 pigs and 10 ml in 4 pigs. Four weeks after treatment, the pigs underwent MRI including MRA and were killed. Norepinephrine (NE) concentration in the renal parenchyma served as a surrogate parameter to analyze the efficacy of sympathetic denervation. In addition, the renal artery and sympathetic nerves were examined histologically to identify evidence of vascular and neural injury. Results. In pigs treated with 10 ml ethanol, treatment resulted in neural degeneration. We found a significant reduction of NE concentration in the kidney parenchyma of 53 % (p < 0.02) compared with the untreated contralateral kidney. In pigs treated with 5 ml ethanol, no significant changes in histology or NE were observed. There was no evidence of renal arterial stenosis in MRI, macroscopy or histology in any pig. Conclusion. MR-guided periarterial ethanol injection was feasible and efficient for renal sympathetic denervation in a swine model. This technique may be a promising alternative to the catheter-based approach in the treatment of resistant arterial hypertension.
62 RADIOLOGY AND NUCLEAR MEDICINE↗
Integral Experiment Request 523 Feasibility Study (Summary Report)
This report documents the feasibility phase of the Critical Experiment Design (CED) conducted as part of integral experiment request (IER) 523. The purpose of IER-523 is to explore the effects of using 35 weight percent enriched uranium dioxide-beryllium oxide (UO 2 -BeO) material on critical configurations using the Seven Percent Critical Experiment (7uPCX) at Sandia National Laboratories (Sandia). Preliminary experiment design concepts, neutronic analysis results, and proposed paths for continuing the CED process are presented.
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
Feasibility study of low angle planetary entry
The feasibility of a Jovian entry by a probe originally designed for Saturn and Uranus entries is examined. An entry probe is described which is capable of release near an outer planet's sphere of influence and descent to a predetermined target entry point in the planet's atmosphere. The probe is designed so as to survive the trapped particle radiation belts and an entry heating pulse. Data is gathered and relayed to an overflying spacecraft bus during descent. Probe variations for two similar missions are described. In the first flyby of Jupiter by a Pioneer spacecraft launched during the 1979 opportunity is examined parametrically. In the second mission an orbiter based on Pioneer and launched in 1980 is defined in specific terms. The differences rest in the science payloads and directly affected wiring and electronics packages.
Defrees, R. E.↗
Atmospheric science facility pallet-only mode space transportation system payload (feasibility study), Volume 1
The economic and technical feasibility is assessed of employing a pallet-only mode for conducting Atmospheric Magnetospheric Plasmas-in-Space experiments. A baseline design incorporating the experiment and instrument descriptions is developed. The prime instruments are packaged into four pallets in a physical and functional manner compatible with the Space Transportation System capabilities and/or constraints and an orbiter seven-day mission timeline. Operational compatibility is verified between the orbiter/payload and supporting facilities. The development status and the schedule requirements applicable to the Atmospheric Science Facility mission are identified. Conclusions and recommendations are presented and discussed.
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A feasibility study of using advanced external beam techniques to create a vaginal cuff brachytherapy-like endometrial boost plan
The purpose of this study was to explore the feasibility of using advanced external beam radiation therapy (EBRT) planning techniques for creating plans that could be used as a possible alternative for high-dose rate (HDR) vaginal cuff brachytherapy (VCBT) boost in treating endometrial cancer. The computed tomography (CT) images of a total of 4 female patients who had endometrial cancer treated with HDR-VCBT were selected for this study. A typical HDR-VCBT target volume, 0.5-cm-thick shell volume around the cylinder applicator in the prescribed treatment length was contoured and used as the planning target volume (PTV) in both the HDR VCBT and the EBRT VCBT-like plans. HDR-VCBT plans were made based on the clinical protocol, 6 Gy given at the cylinder surface. The EBRT plans were generated using either a 7-field intensity-modulated radiation therapy (IMRT) or a 2-arc volumetric-modulated arc therapy (VMAT) techniques for different cylinder sizes and treatment lengths, with the prescription dose of 5 Gy. Organs at risk (OARs) such as bladder, femoral heads, rectum, and sigmoid were also contoured and used in dosimetric evaluations. Dose-to-target metrics included mean dose, the dose covering 90% of target volume (D90) and the percentage of target volume covered by 90% of prescription dose (V90 or V13.5 Gy). Dose to OAR metrics included the maximum dose received by 0.1 cc (D0.1cc), 1.0 cc (D1.0cc), and 2.0 cc (D2.0cc) of OARs. These metrics were calculated and compared between all techniques. After the EBRT plans were normalized to achieve a comparable mean dose to target as HDR-VCBT, the EBRT plans were found to have superior target coverage and increased dose homogeneity compared with HDR-VCBT. V90s of EBRT plans were 95%, compared with 50% to 58% of the HDR plans. However, D0.1cc, D1.0cc, and D2.0cc of OARs were 2% to 38% lower in HDR-VCBT than in EBRT. Although HDR-VCBT plans demonstrated superior normal tissue sparing, both EBRT and HDR-VCBT plans produce plans that met clinical dose constraints on normal tissues. Advanced EBRT techniques such as IMRT and VMAT are capable of making plans, which closely resemble HDR-VCBT. Although the doses of OARs are greater in EBRT than in HDR-VCBT, the prescription dose coverage and dose homogeneity of the EBRT plans are greater than that of HDR-VCBT plans at the similar mean dose, and the OAR dose is still acceptable with EBRT plans. The detailed dosimetric approaches are provided in the study.
62 RADIOLOGY AND NUCLEAR MEDICINE↗
Feasibility Study on MR-Guided High-Intensity Focused Ultrasound Ablation of Sciatic Nerve in a Swine Model: Preliminary Results
IntroductionSpastic patients often seek neurolysis, the permanent destruction of the sciatic nerve, for better pain management. MRI-guided high-intensity focused ultrasound (MRgHIFU) may serve as a noninvasive alternative to the prevailing, more intrusive techniques. This in vivo acute study is aimed at performing sciatic nerve neurolysis using a clinical MRgHIFU system.MethodsThe HIFU ablation of sciatic nerves was performed in swine (n = 5) using a HIFU system integrated with a 3 T MRI scanner. Acute lesions were confirmed using T1-weighted contrast-enhanced (CE) MRI and histopathology using hematoxylin and eosin staining. The animals were euthanized immediately following post-ablation imaging.ResultsReddening and mild thickening of the nerve and pallor of the adjacent muscle were seen in all animals. The HIFU-treated sections of the nerves displayed nuclear pyknosis of Schwann cells, vascular hyperemia, perineural edema, hyalinization of the collagenous stroma of the nerve, myelin sheet swelling, and loss of axons. Ablations were visible on CE MRI. Non-perfused volume of the lesions (5.8–64.6 cc) linearly correlated with estimated lethal thermal dose volume (4.7–34.2 cc). Skin burn adjacent to the largest ablated zone was observed in the first animal. Bilateral treatment time ranged from 55 to 138 min, and preparation time required 2 h on average.ConclusionThe acute pilot study in swine demonstrated the feasibility of a noninvasive neurolysis of the sciatic nerve using a clinical MRgHIFU system. Results revealed that acute HIFU nerve lesions were detectable on CE MRI, gross pathology, and histology.
62 RADIOLOGY AND NUCLEAR MEDICINE↗