bluuebunny/crossref_metadata_2025 huggingface dataset:
Credibility clusters, preferences, and helpfulness beliefs for specific forms of psychotherapy
Authors: Sandell Rolf , Clinton David , Frövenholt Josefin , Bragesjö Maria
Published: April 2011

Background. There is some evidence that the perceived credibility of specific forms of psychotherapy, beliefs about helpful and not‐so‐helpful interventions, and differential treatment preferences may influence both therapeutic alliance and outcome, at least in the short term. The present study explored whether distinct clusters exist, based on credibility ratings, and how these may be related to treatment preferences and beliefs about the helpfulness of specific interventions.

Method. Written descriptions of psychodynamic, cognitive, and cognitive‐behavioural psychotherapy were rated by a random community sample with the ‘normal’ level of psychiatric treatment (n= 121), psychiatric outpatients with limited previous experience of psychiatric care (n= 118), and a group of psychiatric ‘veterans’ with long experience of psychiatric care (n= 48). Participants completed a questionnaire focusing on beliefs about the helpfulness of specific therapy components, rated the credibility of each form of psychotherapy, and ranked the alternatives in terms of preferences.

Results. Using cluster analysis, six distinct groups of participants were delineated. Some approached psychotherapy in an undifferentiated manner, tending to either embrace all or reject all of the methods examined. Others had differentiated ideas about the credibility of specific therapeutic approaches. These clusters were strongly associated with differential treatment preferences. They were also associated with helpfulness beliefs, type of psychological problems, previous experiences with psychotherapy, and gender. Analysis of the interactions among these factors revealed that the distribution across clusters was almost entirely accounted for by the helpfulness beliefs.

Conclusions. For clinicians, it may be important to investigate the differential appeal of specific components of psychotherapy as well as entire therapy packages in individual cases prior to commencing therapy. For researchers, it may be important to consider whether outcome studies would become more informative by taking patients’ beliefs and preferences into account.
Unsteady Pressure Measurements With a Fast Response Cooled Probe in High Temperature Gas Turbine Environments
Authors: Mersinligil Mehmet , Brouckaert Jean-François , Desset Julien
Published: April 2011

This paper presents the first experimental engine and test rig results obtained from a fast response cooled total pressure probe. The first objective of the probe design was to favor continuous immersion of the probe into the engine to obtain a time series of pressure with a high bandwidth and, therefore, statistically representative average fluctuations at the blade passing frequency. The probe is water cooled by a high pressure cooling system and uses a conventional piezoresistive pressure sensor, which yields, therefore, both time-averaged and time-resolved pressures. The initial design target was to gain the capability of performing measurements at the temperature conditions typically found at high pressure turbine exit (800–1100°C) with a bandwidth of at least 40 kHz and in the long term at combustor exit (2000 K or higher). The probe was first traversed at the turbine exit of a Rolls-Royce Viper turbojet engine at exhaust temperatures around 750°C and absolute pressure of 2.1 bars. The probe was able to resolve the high blade passing frequency (≈23 kHz) and several harmonics of up to 100 kHz. Besides the average total pressure distributions rom the radial traverses, phase-locked averages and random unsteadiness are presented. The probe was also used in a virtual three-hole mode yielding unsteady yaw angle, static pressure, and Mach number. The same probe was used for measurements in a Rolls-Royce intermediate pressure burner rig. Traverses were performed inside the flame tube of a kerosene burner at temperatures above 1600°C. The probe successfully measured the total pressure distribution in the flame tube and typical frequencies of combustion instabilities were identified during rumble conditions. The cooling performance of the probe is compared with estimations at the design stage and found to be in good agreement. The frequency response of the probe is compared with cold shock-tube results and a significant increase in the natural frequency of the line-cavity system formed by the conduction cooled screen in front of the miniature pressure sensor were observed.
A Sub-idle Compressor Characteristic Generation Method With Enhanced Physical Background
Authors: Zachos Pavlos K. , Aslanidou Ioanna , Pachidis Vassilios , Singh Riti
Published: April 2011

Sub-idle is a very challenging operating region as the performance of a gas turbine engine changes significantly compared with design conditions. In addition, the regulations for new and existing engines are becoming stricter and the prediction of engine relight capability is essential. In order to predict the performance of an engine, detailed component maps are required. The data obtained from rig tests are insufficient at low speeds, creating the need for generation of maps within the sub-idle regime. The first step toward this direction is the use of an extrapolation process. This is a purely mathematical process and the results are not usually of sufficient accuracy. In addition, this method does not provide any insight on the physical phenomena governing the operation of the compressor at low speeds. The accuracy of the resulting compressor map can be increased with a better low speed region definition; this can be achieved via the thorough study of a locked rotor compressor, enabling the derivation of the zero rotational speed line and allowing an interpolation process for the generation of the low speed part of the characteristic. In this work, an enhanced sub-idle compressor map generation technique is proposed. The suggested methodology enables the generation of characteristics at far off-design conditions with enhanced physical background. Alternative parameters for map representation are also introduced. Provided that the all the blade rows of the compressor are of known geometry, a numerical analysis is used for the calculation of the characteristic of the half stage and a stage stacking method is employed to create the entire compressor characteristic. This way, the sub-idle region of the map can be calculated through interpolation, which provides a more accurate and predictive technique. Application of the method for compressor map generation showed that the proposed interpolation approach is robust and capable of enhancing any performance simulation tool used for the prediction of transient altitude relight or ground-starting maneuvers.
Estimation of Road Friction Coefficient Based on the Brush Model
Authors: Nishihara Osamu , Masahiko Kurishige
Published: April 2011

Road friction coefficients are highly effective for advanced vehicle control technologies, although the estimation at four individual tires has not been practically used for ordinary vehicles. This study describes the essential relation between the tire forces and the aligning torque that can be rearranged as an estimation equation for the grip margin. The grip margin is readily convertible into the friction coefficient. The brush model is reanalyzed, beginning from the conventional simple physical model, and intrinsic expressions are derived. The grip margin, which is defined as the residual tire force normalized by the radius of friction circle, was estimated using three components of the tire forces and the aligning torque. A simple cubic equation is obtained as a grip margin equation for an isotropic brush model. Previous studies assumed an anisotropic brush model and obtained an imperfect quintic equation. In the present study, a new term is added to the algebraic equation, which was shown to be consistent with the isotropic model. The solutions to the equations are approximated by Chebyshev polynomials. The estimation methods are tested by numerical simulations using CarSim, which is a popular vehicle simulation software application. The estimated friction coefficients agree well with the values that are set during each run of the simulations, especially for the cases of smaller grip margins and lower friction conditions.
Boundaries Effects on the Movements of a Sphere Immersed in a Free Surface Flow
Authors: Mirauda D. , Plantamura A. Volpe , Malavasi S.
Published: April 2011

This work analyzes the influence of boundary conditions on the movements of a sphere immersed in a steady free surface flow. The sphere is free to move both in the transverse and streamwise directions and it is characterized by the values of the mass ratio m∗ equal to 1.34 and of the damping ratio ζ equal to 0.004. In all the experiments the blockage coefficient is kept constant, while the sphere is located at different distances from the free surface and from the bottom wall of the channel. The movements of the sphere have been measured by means of the image analysis of a charge coupled device camera which provides the 2D (streamwise and transverse) displacements of the sphere with a temporal resolution of 0.02 s. The experimental data show a significant influence of the boundaries on the sphere movement and highlight a different behavior of the amplitude response between the three different experimental setups considered.
Dynamic Response of Prestressed Rayleigh Beam Resting on Elastic Foundation and Subjected to Masses Traveling at Varying Velocity
Authors: Oni S. T. , Omolofe B.
Published: April 2011

In this study, the dynamic response of axially prestressed Rayleigh beam resting on elastic foundation and subjected to concentrated masses traveling at varying velocity has been investigated. Analytical solutions representing the transverse-displacement response of the beam under both concentrated forces and masses traveling at nonuniform velocities have been obtained. Influence of various parameters, namely, axial force, rotatory inertia correction factor, and foundation modulus on the dynamic response of the dynamical system, is investigated for both moving force and moving mass models. Effects of variable velocity on the vibrating system have been established. Furthermore, the conditions under which the vibrating systems will experience resonance effect have been established. Results arrived at in this paper are in perfect agreement with existing results.
Design and Analysis of a New Type of Electromagnetic Damper With Increased Energy Density
Authors: Zuo Lei , Chen Xiaoming , Nayfeh Samir
Published: April 2011

Eddy current dampers, or electromagnetic dampers, have advantages of no mechanical contact, high reliability, and stability, but require a relatively large volume and mass to attain a given amount of damping. In this paper, we present the design and analysis of a new type of eddy current damper with remarkably high efficiency and compactness. Instead of orienting the magnetic field in a uniform direction, we split the magnetic field into multiple ones with alternating directions so as to reduce the electrical resistance of the eddy current loops and increase the damping force and damping coefficient. In this paper, an analytical model based on the electromagnetic theory for this type of eddy current damper is proposed, and a finite-element analysis (FEA) is carried out to predict the magnetic field and current density. Experimental results agree well with the analytical model and FEA predictions. We demonstrate that the proposed eddy current damper achieves a damping density (N s/m m3) and a dimensionless damping constant as much as 3–5 times as those in the literature. The dependence of damping on velocity and frequency is also examined.
Thermal Nonequilibrium and Viscous Dissipation in the Thermal Entrance Region of a Darcy Flow With Streamwise Periodic Boundary Conditions
Authors: Barletta A. , Rossi di Schio E. , Selmi L.
Published: April 2011

The thermal entrance region in a plane-parallel channel filled by a fluid saturated porous medium is investigated with reference to steady forced convection and to a thermal boundary condition given by a wall temperature longitudinally varying with a sinusoidal law. The effect of viscous dissipation in the fluid is taken into account, and a two-temperature model is employed in order to evaluate separately the local fluid and solid matrix temperatures. The asymptotic temperature distributions are determined analytically. The governing equations in the thermal entrance region are solved numerically by a finite element method and by the method of lines.
Chemical Decontamination for Decommissioning (DFD) and DFDX
Authors: Morris Ronald
Published: April 2011

DFD is an acronym for the “Decontamination for Decommissioning” process developed in 1996 by the Electric Power Research Institute (EPRI). The process was designed to remove radioactivity from the surfaces of metallic components to allow these components to be recycled or free-released for disposal as non-radioactive. DFD is a cyclic process consisting of fluoroboric acid, potassium permanganate and oxalic acid. The process continues to uniformly remove base metal once oxide dissolution is complete. The DFD process has been applied on numerous components, sub-systems and systems including the reactor systems at Big Rock Point and Maine Yankee in the United States, and the Jose Cabrera (Zorita) Nuclear Power Plant (NPP) in Spain. The Big Rock Point site has been returned to Greenfield and at Maine Yankee the land under the license was reduced for an Independent Spent Fuel Storage Installation (ISFSI). In the upcoming months the Zorita NPP in Spain will initiate dismantlement and decommissioning activities to return the site to a non-nuclear facility. The development of the EPRI DFD process has been an ongoing evolution and much has been learned from its use in the past. It is effective in attaining very high decontamination factors; however, DFD also produces secondary waste in the form of ion exchange resins. This secondary waste generation adds to the decommissioning quota but this can be improved upon at a time when radioactive waste storage at nuclear facilities and waste disposal sites is limited. To reduce the amount of secondary waste, EPRI has developed the DFDX process. This new process is an enhancement to the DFD process and produces a smaller amount of metallic waste rather than resin waste; this reduction in volume being a factor of ten or greater. Electrochemical ion exchange cells are the heart of the DFDX system and contain electrodes and cation ion exchange resin. It has been used very successfully in small system applications and the next evolution is to design, build and implement a system for the chemical decontamination for decommissioning of larger reactor systems and components, and Full System Decontamination (FSD). The purpose of this paper is to provide a reference point for those planning future chemical decontaminations for plant decommissioning. It is based on actual experience from the work already performed to date and the planned development of the DFDX process.
Study on Influence of Nuclear Fuel Material Management and Transfer Scenarios on Decommissioning
Authors: Mizukoshi Kazuma
Published: April 2011

The Japanese electric utilities are required to prepare plans to transfer its nuclear fuel material by the end of the decommissioning period. (1) There can be several scenarios regarding the management and transfer of nuclear fuel material. It is necessary to fully understand the characteristics of individual scenarios so that the most suitable method can be selected according to the conditions specific to each plant.
In Situ Stress Measurements in Siliceous Mudstones at Horonobe Underground Research Laboratory, Japan
Authors: Sanada Hiroyuki , Nakamura Takahiro , Sugita Yutaka
Published: April 2011

The stress measurement methods implemented during the surface-based investigations and during construction of the underground facilities in the Horonobe mudstones, as well as information on the initial stress state around the Horonobe URL, are described in this paper. During the surface-based investigations, determination of deep in situ stress was conducted using HF, BB information in deep boreholes and core-based methods such as AE and DSCA. During construction of the underground facilities, subsurface investigations utilizing CCBO, HTPF and the monitoring of spalling around the shafts were conducted in order to verify results from initial stress measurements in the surface-based investigations. HF results indicate that magnitude of the horizontal maximum and minimum principal stresses increases linearly with depth. The maximum principal stress estimated from the HF and borehole breakout data is almost E-W. This is similar to the tectonic movement direction in the vicinity of the Horonobe URL. Due to tectonic movement, horizontal maximum stress is almost 1.5 times larger than the horizontal minimum stress. The minimum horizontal principle stress is almost equivalent to overburden pressure. Stress condition determined from HTPF in the investigations during construction of the underground facilities is almost equal to the results during surface-based investigations.
Estimation and Measurement of Porosity Change in Cement Paste
Authors: Lee Eunyong , Jung Haeryong , Kwon Ki-jung , Kim Do-Gyeum
Published: April 2011

Laboratory-scale experiments were performed to understand the porosity change of cement pastes. The cement pastes were prepared using commercially available Type-I ordinary Portland cement (OPC). As the cement pastes were exposed in water, the porosity of the cement pastes sharply increased; however, the slow decrease of porosity was observed as the dissolution period was extended more than 50 days. As expected, the dissolution reaction was significantly influenced by w/c raito and the ionic strength of solution. A thermodynamic model was applied to simulate the porosity change of the cement pastes. It was highly influenced by the depth of the cement pastes. There was porosity increase on the surface of the cement pastes due to dissolution of hydration products, such as portlandite, ettringite, and CSH. However, the decrease of porosity was estimated inside the cement pastes due to the precipitation of cement minerals.
Improvement of Quicklime Mixing Treatment by Carbon Dioxide Ventilation
Authors: Nakagawa Yuki , Hashimoto Hisayoshi , Suto Koichi , Inoue Chihiro
Published: April 2011

This paper describes a fundamental examination of a quicklime mixing treatment combined with carbon dioxide ventilation for the remediation process of soils polluted with volatile organic compounds (VOCs). The quicklime mixing treatment is widely applied to remove volatile pollutants in soils using the heat of reaction with quicklime and pore water. To maintain a higher temperature and to ensure that most of the VOCs are volatilized, quicklime is usually mixed at a ratio of 10% with soils in this treatment. However, a surplus of added quicklime results in higher (alkaline) soil pH and causes serious damage to the soil ecosystems. To solve this problem, the simultaneous ventilation of carbon dioxide during quicklime mixing with polluted soil was examined. Under these conditions calcium hydroxide is generated by the reaction of quicklime with pore water; the calcium hydroxide then reacts with carbon dioxide to produce additional heat of reaction. It is expected that the heat from the second reaction can be used for the pollutant treatment, allowing the amount of quicklime addition for the treatment to be reduced. Laboratory experiments showed that more than half of the calcium hydroxide was changed to calcium carbonate when the mixed soil sample was ventilated by carbon dioxide, using mixing ratios of 5% quicklime and 5% water in the soil. The maximum soil temperature reached with this treatment was the same as that for the treatment using 10% quicklime. Scale-up experiments confirmed the effectiveness of using carbon dioxide ventilation.
Low Alkaline Cement Used in the Construction of a Gallery in the Horonobe Underground Research Laboratory
Authors: Nakayama Masashi , Sato Haruo , Sugita Yutaka , Ito Seiji , Minamide Masashi , Kitagawa Yoshito
Published: April 2011

In Japan, any high level radioactive waste (HLW) repository is to be constructed at over 300 m depth below surface. Tunnel support is used for safety during the construction and operation, and shotcrete and concrete lining are used as the tunnel support. Concrete is a composite material comprised of aggregate, cement and various admixtures. Low alkaline cement has been developed for the long term stability of the barrier systems whose performance could be negatively affected by highly alkaline conditions arising due to cement used in a repository. Japan Atomic Energy Agency (JAEA) has developed a low alkaline cement, named as HFSC (Highly Fly-ash Contained Silicafume Cement), containing over 60 wt% of silica-fume (SF) and fly-ash (FA). HFSC was used experimentally as the shotcrete material in construction of part of the 140m deep gallery in the Horonobe Underground Research Laboratory (URL). The objective of this experiment was to assess the performance of HFSC shotcrete in terms of mechanics, workability, durability, and so on. HFSC used in this experiment is composed of 40 wt% OPC (Ordinary Portland Cement), 20 wt% SF, and 40 wt% FA. This composition was determined based on mechanical testing of various mixes of the above components. Because of the low OPC content, the strength of HFSC tends to be lower than that of OPC. The total length of tunnel using HFSC shotcrete is about 73 m and about 500 m3 of HFSC was used. The workability of HFSC shotcrete was confirmed in this experimental construction.
A Study on Groundwater Infiltration in the Horonobe Area, Northern Hokkaido, Japan
Authors: Yokota Hideharu , Yamamoto Yoichi , Maekawa Keisuke , Hara Minoru
Published: April 2011

In the Horonobe area of northern Hokkaido, the Japan Atomic Energy Agency has been carrying out various hydrological observations to estimate the recharge rate. Subsurface earth temperature and soil moisture content have been observed at HGW-1 site (GL-0.7m to GL-2.3m, since 2005) and Hokushin Meteorological Station (GL-0.1m to GL-1.1m, since 2008). The results have revealed groundwater infiltration and recharge occurring throughout year, the shallow groundwater-infiltration velocity depending on the depth and the position of the Zero Flux Plane. For the estimation of boundary conditions in groundwater flow simulation, in this study, the shallow groundwater-flow system has been examined qualitatively on the basis of the variation of the subsurface earth temperature and the soil moisture content. In the future, it is necessary to quantitatively assess the shallow groundwater infiltration and recharge rate, the intermediate runoff, and the evapotranspiration based on the observed data of the weighing lysimeter, and the other measurement stations in the area.
Development of Comprehensive Techniques for Coastal Site Characterisation: Part 3—Conceptualisation of Long-Term Geosphere Evolution
Authors: Niizato Tadafumi , Amano Kenji , Ota Kunio , Kunimaru Takanori , Lanyon Bill , Alexander W. Russell
Published: April 2011

A critical issue for building confidence in the long-term safety of geological disposal is to demonstrate the stability of the geosphere, taking into account its likely future evolution. An ongoing collaborative programme aims to establish comprehensive techniques for characterising the overall evolution of coastal sites through studying the palaeohydrogeological evolution in the coastal system around the Horonobe area, Hokkaido, northern Japan. Information on natural events and processes related to the palaeohydrogelogical evolution of the area have been integrated into the chronological tables and conceptual models that indicates the temporal and spatial sequences of the events and processes, such as climatic and sea-level changes, palaeogeography, and geomorphological and geological evolution in the area. The methodology for conceptualisation of the geosphere evolution will be applied to other analogous coastal areas on Japan’s western seaboard to produce comprehensive techniques to support understanding the geosphere evolution of potential coastal sites for deep geological repositories.
Technical Know-How for Modeling of Geological Environment: Part 1—Overview and Groundwater Flow Modeling
Authors: Saegusa Hiromitsu , Takeuchi Shinji , Maekawa Keisuke , Osawa Hideaki , Semba Takeshi
Published: April 2011

It is important for site characterization projects to manage the decision-making process with transparency and traceability and to transfer the technical know-how accumulated during the research and development to the implementing phase and to future generations. The modeling for a geological environment is to be used to synthesize investigation results. Evaluation of the impact of uncertainties in the model is important to identify and prioritize key issues for further investigations. Therefore, a plan for site characterization should be made based on the results of the modeling. The aim of this study is to support for the planning of initial surface-based site characterization based on the technical know-how accumulated from the Mizunami Underground Research Laboratory Project and the Horonobe Underground Research Laboratory Project. These projects are broad scientific studies of the deep geological environment that are a basis for research and development for the geological disposal of high-level radioactive wastes. In this study, the work-flow of the groundwater flow modeling, which is one of the geological environment models, and is to be used for setting the area for the geological environment modeling and for groundwater flow characterization, and the related decision-making process using literature data have been summarized.
Current Status of Horonobe URL Project in Construction Phase
Authors: Abe Hironobu , Hatanaka Koichiro
Published: April 2011

The Horonobe URL project has been pursued by JAEA (Japan Atomic Energy Agency) to establish and demonstrate site characterization methodologies, engineering technologies, and safety assessment methodologies for HLW geological disposal in relevant geological environment with sedimentary rock and saline groundwater distributing in the Horonobe area, Hokkaido, Japan. In the Horonobe URL project, surface-based investigation phase (Phase I) has already completed in the fiscal year 2005, and then construction phase (Phase II) has initiated in the same year. Currently, construction of the underground facilities such as shafts/galleries which were designed in Phase I, investigations of the geological environment in the excavated shafts/galleries and confirmation of applicability of engineering technologies have been alternately carried out as Phase II activities of the project. During the construction so far, monitoring for the construction safety such as convergence measurements, tunnel wall observation, sampling of groundwater and rock, investigations for evaluating excavation damaged/disturbed zone (EDZ/EdZ) along shafts/galleries were carried out. In addition, a shotcrete construction test and a grout injection test by using low alkaline cement material were carried in the horizontal galleries. In this paper, status of the URL construction and research activities mentioned above are outlined as the current achievement of the Horonobe URL project.
Radioactive Waste: Feedback of 40-Year Operations in France
Authors: Dutzer Michel , Ouzounian Ge´rald , Miguez Roberto , Tison Jean-Louis
Published: April 2011

France’s experience in the management of radioactive waste is supported by forty years of operational activities in the field of surface disposal. This feedback is related to three disposal facilities: Centre de la Manche disposal, not far away Cherbourg, from design to post-closure facility. Centre at Soulaines-Dhuys from site selection to design to operation during nearly 20 years. Centre at Morvilliers from site selection to operation for seven years now. During the operational period of Centre de la Manche disposal facility (1969–1994), the safety concept for low- and intermediate level short lived waste (LIL-SLW) was developed and progressively incorporated in the procedures of the facility. The facility entered its institutional control period and the experience of this facility has been useful for the operating facilities. Centre de l’Aube that took over Centre de la Manche, and Morvilliers for very low level wastes. Both facilities currently accommodate the major part of the volume of radioactive wastes that are generated in France. However disposal facilities have to be considered as rare resources. Then new waste management options are being investigated as the disposal of large components or recycling metallic wastes within the nuclear industry.
Sorption Behavior of Iodine on Calcium Silicate Hydrates Formed as a Secondary Mineral
Authors: Shirai Keisuke , Niibori Yuichi , Kirishima Akira , Mimura Hitoshi
Published: April 2011

This study examined the sorption behaviors of iodine into CSH gel without dried processes, considering the repository system saturated with groundwater after the backfilling. In glove box saturated with N2 gas, each sample of CSH gel was synthesized with CaO, SiO2, and distilled water with liquid/solid ratio 20. Then, 1 mM iodine solution is added into the aqueous solution including the CSH gel with various Ca/Si molar ratios under the isothermal condition (298 K). In the results, even if the Ca/Si ratio is relatively small (<1.0), the distribution coefficients (Kd) of iodine on CSH gel without dried processes were two-order of magnitude larger than those with dried processes. For example, the value of Kd (ml/g) was about 380 in the case of 0.5 in Ca/Si molar ratio. Furthermore, it was confirmed the sorption behavior attain equilibrium in 24 hours. These suggest secondary mineral of CSH gel would retard the migration of anionic nuclides under the condition saturated with groundwater. In comparison, this study prepared also the co-precipitated samples of CSH gel and iodine, where the 1 mM iodine solution is added before curing the CSH gel. These distribution coefficients and the kinetics almost agreed with those mentioned above.
Overview of NUMO’s Policy for Implementing Safe Geological Disposal and Developing Supporting Technologies
Authors: Tsuchi H. , Ishiguro K. , Deguchi A. , Takahashi Y. , Kaku K.
Published: April 2011

Based on the Act on Final Disposal of Specified Radioactive Waste, the Nuclear Waste Management Organization of Japan (NUMO) was established in October 2000 as the implementing organization for geological disposal of the radioactive waste. Since its establishment NUMO has been developing the technologies required for implementation of the project and initiated the solicitation of the disposal site by volunteering from the municipalities. However, no effective application has been received as yet to initiate the site investigation. Thus NUMO decided to prepare the NUMO 2010 Technical Report as a tool for improving the general understanding of the geological disposal project. The report will present the safety policy that describes how NUMO aims to achieve safe geological disposal through the ca.100-year-long project and will document the progress made with developing the technologies that support the safety concept. Three policies for ensuring safety are described namely a) staged and flexible project implementation and decision making based on iterative confirmation of safety, b) project implementation based on reliable technologies and c) technical activities for building confidence in NUMO’s safety concept. The report also summarizes the technological development for implementation of the geological disposal project in Japan.
An Empirical Model to Determine the Modes of Corrosion of Carbon Steel Under Near Field Environments of Geological Disposal
Authors: Maeda Toshikatsu , Watanabe Masatoshi , Takeda Seiji , Nakayama Shinichi
Published: April 2011

Carbon steel is an alloy that can be passivated and be attacked by localized corrosion under certain water chemistries. For example, it is known that carbon steel is passivated in solutions above pHd; the pH at general corrosion/passivation transition. In this study, an empirical model was developed to determine whether near field environments fall in the passivation or non-passivation domain for carbon steel. Using the experimental data obtained by previous studies, the pHd was defined as a function of four factors, where the activity of proton ion ([H+]) for pHd is assumed to be a linear combination of the logarithms of the total carbonate concentration ([C]), the chloride ion concentration ([Cl−]), the limiting current density of dissolved oxygen diffusion (iO2), and the inverse of absolute temperature of contacting solution (T). The derived equation fitted well with experimental data from previous studies.
Advancing the Use of IAEA Networks in Radioactive Waste Management: Past Successes, Present Challenges and Future Opportunities
Authors: Degnan P. , Mele I. , Dinner P. , Monken-Fernandes H. , Morales Leon A. , Nachmilner L. , Kinker J. , Hossain S.
Published: April 2011

Since 2001 the International Atomic Energy Agency has championed the concept and use of Networks to advance radioactive waste management across the globe. At the present time there are four Networks managed on behalf of Member States by the IAEA and a fifth one is currently being implemented. The scopes of interest covered by the Networks encompass near-surface and deep geological disposal, the decommissioning of nuclear facilities, the environmental remediation of sites contaminated with radioactive materials and the characterisation of low- and intermediate-level radioactive wastes. To date over 100 organisations from more than 40 Member States are involved in the Networks. Many of these Network participants generously donate resources, time and effort to support Network activities, while others with nascent or otherwise less well developed programmes are still in the process of acquiring experience, capabilities and know-how. Regardless of the stage of development, all Network participants share in the mutual benefits that arise from improved communications with sister organisations and the sharing of experience and knowledge. The universal Goal of the Networks is the promotion of methods and technologies that will enhance the safety and sustainability of radioactive waste management practices and facilities. This Goal is being achieved through continuous improvements in communication and knowledge sharing between Network participants and the provision of enhanced opportunities for training, involvement in demonstration projects and the development of novel technologies and methodologies. We recognise that interdisciplinary understanding and the coordination of efforts at key interfaces at the back-end of the fuel cycle are critical aspects for achieving the Network Goal efficiently and effectively. Consequently, the IAEA Networks that will be operational by the end of 2010 are themselves are being molded into an organic “Network of Networks” where the use of new electronic media and the possibilities presented by enhanced communication channels will be exploited. Here we provide an overview of the IAEA Networks in radioactive waste management and present a new tool that is under development, an internet-based portal for enhanced communications and the provision of improved training opportunities.
Transuranic (TRU) Waste Volume Reduction Operation at a Plutonium Facility
Authors: Cournoyer Michael E. , Nixon Archie E. , Fife Keith W. , Sandoval Arnold M. , Garcia Vincent E. , Dodge Robert L.
Published: April 2011

Programmatic operations at the Los Alamos National Laboratory Plutonium Facility (TA-55) involve working with various amounts of plutonium and other highly toxic, alpha-emitting materials. The spread of radiological contamination on surfaces, airborne contamination, and excursions of contaminants into the operator’s breathing zone are prevented through use of a variety of gloveboxes (the glovebox, coupled with an adequate negative pressure gradient, provides primary confinement). Size-reduction operations on glovebox equipment are a common activity when a process has been discontinued and the room is being modified to support a new customer. The Actinide Processing Group at TA-55 uses one-meter or longer glass columns to process plutonium. Disposal of used columns is a challenge, since they must be size-reduced to get them out of the glovebox. The task is a high-risk operation because the glass shards that are generated can puncture the bag-out bags, leather protectors, glovebox gloves, and the worker’s skin when completing the task. One of the Lessons Learned from these operations is that Laboratory management should critically evaluate each hazard and provide more effective measures to prevent personnel injury. A bag made of puncture-resistant material was one of these enhanced controls. We have investigated the effectiveness of these bags and have found that they safely and effectively permit glass objects to be reduced to small pieces with a plastic or rubber mallet; the waste can then be easily poured into a container for removal from the glovebox as non-compactable transuranic (TRU) waste. This size-reduction operation reduces solid TRU waste volume generation by almost 2-1/2 times. Replacing one-time-use bag-out bags with multiple-use glass crushing bags also contributes to reducing generated waste. In addition, significant costs from contamination, cleanup, and preparation of incident documentation are avoided. This effort contributes to the Los Alamos National Laboratory Continuous Improvement Program by improving the efficiency, cost-effectiveness, and formality of glovebox operations. In this report, the technical issues, associated with implementing this process improvement are addressed, the results discussed, effectiveness of Lessons Learned evaluated, and waste savings presented.
Development of Methodology to Construct a Generic Conceptual Model of River-Valley Evolution for Performance Assessment of HLW Geological Disposal
Authors: Kawamura Makoto , Tanikawa Shin-ichi , Niizato Tadafumi , Yasue Ken-ichi
Published: April 2011

In order to assess the long-term safety of a geological disposal system for high-level radioactive waste (HLW), it is important to consider the impact of uplift and erosion, which cannot be precluded on a timescale in the order of several hundred thousand years for many locations in Japan. Geomorphic evolution, caused by uplift and erosion and coupled to climatic and sea-level changes, will impact the geological disposal system due to resulting spatial and temporal changes in the disposal environment. Degradation of HLW barrier performance will be particularly significant when the remnant repository structures near, and are eventually exposed at, the ground surface. In previous studies, fluvial erosion was identified as the key concern in most settings in Japan. Interpretation of the impact of the phenomena at relevant locations in Japan has led to development of a generic conceptual model which contains the features typical at middle reach of rivers. Here, therefore, we present a methodology for development of a generic conceptual model based on best current understanding of fluvial erosion in Japan, which identifies the simplifications and uncertainties involved and assesses their consequences in the context of repository performance.
The Optimized Risk Management of the Waste From TENORM and Nuclear Industries: How to Harmonize Risk From Various Sources
Authors: Fujikawa Yoko , Shimo Michikuni , Yonehara Hironori , Tujimoto Tadashi
Published: April 2011

We compared the existing regulation on management of radioactive and non-radioactive wastes with the ideal legislation procedures for protection of environment. The comparison revealed the necessity of risk-based regulation, consideration for ethics and cost-effectiveness of the regulation, and optimal usage of regulation resources. In order to assess the cost-effectiveness of several different waste disposal options, the concept of disposal cost per unit radiotoxicity (mSv or m3) in waste (CPR hereafter) was introduced and calculated. The results revealed that current disposal option of high level radioactive waste (underground burial) was more cost-effective than that of TENORM and asbestos containing waste.
An Attempt to Evaluate Horizontal Crustal Movement by Geodetic and Geological Approach in the Horonobe Area, Northern Hokkaido, Japan
Authors: Tokiwa Tetsuya , Asamori Koichi , Niizato Tadafumi , Nohara Tsuyoshi , Matsuura Yuki , Kosaka Hideki
Published: April 2011

In this study, we present the preliminary results for the estimation of a horizontal crustal movement by using geodetic and geological approach in the Horonobe area, northern Hokkaido, Japan. The estimations have been carried out by using a GPS data and a geological cross section obtained by applying balanced-section method. As results of this study, both of the shortening rates estimated by GPS data and balanced-section method indicate several millimeters per year. Namely, there is no contradiction between geodetic and geological data, and it is considered that Horonobe area is still situated similar tendency and magnitude of a crustal movement. It is seemingly considered that geodetic data is unhelpful for estimating the long-term crustal movement, because period of geodetic observations is a very short. However, the result of this study indicates that geodetic data provide valuable information for estimating the long-term crustal movement in the area, and it is considered that geodetic approach play an important role in improvement of the credibility of evaluation for prediction of long-term stability.
Strippable Core-Shell Polymer Emulsion for Decontamination of Radioactive Surface Contamination
Authors: Hwang Ho-Sang , Seo Bum-Kyoung , Lee Kune-Woo
Published: April 2011

In this study, the core-shell composite polymer for decontamination from the surface contamination was synthesized by the method of emulsion polymerization and blends of polymers. The strippable polymer emulsion is composed of the poly(styrene-ethyl acrylate) [poly(St-EA)] composite polymer, poly(vinyl alcohol) (PVA) and polyvinylpyrrolidone (PVP). The morphology of the poly(St-EA) composite emulsion particle was core-shell structure, with polystyrene (PS) as the core and poly(ethyl acrylate) (PEA) as the shell. Core-shell polymers of styrene (St)/ethyl acrylate (EA) pair were prepared by sequential emulsion polymerization in the presence of sodium dodecyl sulfate (SDS) as an emulsifier using ammonium persulfate (APS) as an initiator. Related tests and analysis confirmed the success in synthesis of composite polymer. The products are characterized by FT-IR spectroscopy, TGA that were used, respectively, to show the structure, the thermal stability of the prepared polymer. Two-phase particles with a core-shell structure were obtained in experiments where the estimated glass transition temperature and the morphologies of emulsion particles. Decontamination factors of the strippable polymeric emulsion were evaluated with the polymer blend contents.
Characterization of Radioactive Waste From Side Structural Components of a CANDU Reactor for Decommissioning Applications in Korea
Authors: Ahmed Rizwan , Heo Gyunyoung , Cho Dong-Keun , Choi Jongwon
Published: April 2011

Reactor core components and structural materials of nuclear power plants to be decommissioned have been irradiated by neutrons of various intensities and spectrum. This long term irradiation results in the production of large number of radioactive isotopes that serve as a source of radioactivity for thousands of years for future. Decommissioning of a nuclear reactor is a costly program comprising of dismantling, demolishing of structures and waste classification for disposal applications. The estimate of radio-nuclides and radiation levels forms the essential part of the whole decommissioning program. It can help establishing guidelines for the waste classification, dismantling and demolishing activities. ORIGEN2 code has long been in use for computing radionuclide concentrations in reactor cores and near core materials for various burn-up-decay cycles, using one-group collapsed cross sections. Since ORIGEN2 assumes a constant flux and nuclide capture cross-sections in all regions of the core, uncertainty in its results could increase as region of interest goes away from the core. This uncertainty can be removed by using a Monte Carlo Code, like MCNP, for the correct calculations of flux and capture cross-sections inside the reactor core and in far core regions. MCNP has greater capability to model the reactor problems in much realistic way that is to incorporate geometrical, compositional and spectrum information. In this paper the classification of radioactive waste from the side structural components of a CANDU reactor is presented. MCNP model of full core was established because of asymmetric structure of the reactor. Side structural components of total length 240 cm and radius 16.122 cm were modeled as twelve (12) homogenized cells of 20 cm length each along the axial direction. The neutron flux and one-group collapsed cross-sections were calculated by MCNP simulation for each cell, and then those results were applied to ORIGEN2 simulation to estimate nuclide inventory in the wastes. After retrieving the radiation level of side structural components of in- and ex-core, the radioactive wastes were classified according to the international standards of waste classification. The wastes from first and second cell of the side structural components were found to exhibit characteristics of class C and Class B wastes respectively. However, the rest of the waste was found to have activity levels as that of Class A radio-active waste. The waste is therefore suitable for land disposal in accordance with the international standards of waste classification and disposal.
Remediation of Old Environmental Liabilities in the Nuclear Research Institute Rez plc
Authors: Svoboda Karel , Podlaha Josef
Published: April 2011

The Nuclear Research Institute Rez plc (NRI) after 55 years of activities in the nuclear field produced some environmental liabilities that shall be remedied. There are three areas of remediation: (1) decommissioning of old obsolete facilities (e.g. decay tanks, RAW treatment technology, special sewage system), (2) processing of RAW from operation and dismantling of nuclear facilities, and (3) elimination of spent fuel from research nuclear reactors operated by the NRI. The goal is to remedy the environmental liabilities and eliminate the potential negative impact on the environment. Remediation of the environmental liabilities started in 2003 and will be finished in 2014. The character of the environmental liabilities is very specific and requires special remediation procedures. Special technologies are being developed with assistance of external subcontractors. The NRI has gained many experiences in the field of RAW management and decommissioning of nuclear facilities and will use its facilities, experienced staff and all relevant data needed for the successful realization of the remediation. The most significant items of environmental liabilities are described in the paper together with information about the history, the current state, the progress, and the future activities in the field of remediation of environmental liabilities in the NRI.