A review of the data on multiphase flows indicates significant lateral phase distribution and phase separation may take place. This implies that there are important multidimensional aspects to multiphase flow and that multidimensional models are required to predict the observed data trends.

A state-of-the-art, three-dimensional, four-field, two-fluid model is developed (including the required closure laws) and compared to typical phase distribution and separation data. Good agreement is shown.

A review of fractals and various fractal dimensions is given and applied to typical two-phase data sets. It is shown that two-phase flow regimes have deterministic (as opposed to random) structure.

Static and dynamic bifurcation theory is reviewed and engineering applications are given. Moreover, it is shown that a cascade of period doubling bifurcations is normally the precursor of chaos.

Various chaotic attractors are discussed and analytical techniques for assuring that we have a "strange attractor" are given. Finally, it is shown that a boiling loop may exhibit chaotic behavior.

The purpose of this lecture is to provide a sound basis for a mechanistically-based, four field, two-fluid model for two-phase flow that can accurately predict the flow and distribution of the continuous vapor (cv), continuous liquid (cl), dispersed vapor (dv), and dispersed liquid (dl) fields, and is inherently capable of describing the essential features of vapor/liquid flows for different flow regimes.

The equations will be derived using ensemble averaging. The relation of ensemble averaging to time- and volume-averaging will be discussed. An interpretation of the equations using control volumes will be presented. The concepts of ensemble averaging will be used to derive closure relations for dispersed flow by introducing the "cell model". Finally, the status of the flow of continuous vapor and continuous liquid (separated flow) in a channel or pipe will be presented.

1. Background of this presentation

1.1 Principle of Neutron Capture Therapy

1.2 Brief History of BNCT

1.3 Cell Level Absorbed Dose Characteristics for BNCT

1.4 Neutron Irradiation Condition for BNCT

1.5 Neutron Irradiation Systems for BNCT

2. Remodeling for Neutron Irradiation Facility Mainly for BNCT at the KUR

2.1 The Design Goals and the Philosophy
Advanced Neutron Utilization for NCT with the Safety of the Facility

2^nd Lecture hour: Remodeling is continued, The Optimization Study:

2.2 The Epi-thermal Neutron Moderator

2.3 The Neutron Energy Spectrum Shifter and the Thermal Neutron Filters

2.4 Reflector Element for the Reduction of the Fast Neutron Component

2.5 The Cooling Water Thickness between the Reactor Tank and the Heavy Water Tank

3. The KUR Advanced Clinical Irradiation System Mainly for BNCT

3.1. The Heavy Water Neutron Irradiation Facility of the KUR

3.2 The Radiation Shielding System

3.3 The Irradiation Room and the Entrance Shield Door

3.4 The Remote Carrying System and the Medical Treatment Room

3.5 The Safety Observation System

3.6 The Irradiation Rail Device for basic experiments

4. Basic Characteristics of the Neutron Irradiation Facility of the KUR

4.1 Stability of the KUR Operation

4.2 Irradiation Modes and Basic Irradiation Characteristics

4.3 Characteristics of Dose Distribution for NCT Clinical Irradiation

4.4 Usage and Time Characteristics of the Advanced Clinical Irradiation

4.5 NCT Clinical Irradiations under the Full-power Continuous Operation

4.6 Dose Measurement and Estimation Method at the KUR

5. Boron Concentration Measurement System using Prompt Gamma ray Analysis

5.1 Prompt Gamma ray Analysis System at the KUR

6. Future Plan for the Medical Physics Research at the KUR

6.1 Absorbed Dose Estimation System during Neutron Irradiation (PG-SPECT)

6.2 Accelerator based Neutron Irradiation System for epi-thermal neutron

6.3 Reactor based Neutron Irradiation System for Hyper-thermal neutron

Radiation treatment remains one of the fundamental tools of cancer therapy. The radiation dose received by the tumour must be large enough to produce a great enough cell kill and effect a useful tumour control probability with out undue toxicity to normal surrounding tissues. Nowhere is this more crucial than in the treatment of brain tumours. A fundamental understanding of the mechanisms, responses and sensitivities of biological tissues is requires to effect useful treatment and to limit damaging toxicity.

In this pair of lectures, the nature and evidence for the use of radiation treatment in the brain is described, from the point of view of a translational exercise. From this the criteria for improving radiation treatment will be explored with biological and clinical data. Finally, specific attempts to enhance radiation efficacy using novel means such as stereotactic radiosurgery and radiotherapy, BNCT, oxygen enhancement and radiation sensitive genes will be discussed as examples of strategic dose escalation.

The rapidly increasing body of genetic information, not least through projects like the Human Genome project (HUGO), will rapidly increase our knowledge about genes that will effect radiation sensitivity. Different organs of the human body have greatly differing responses to partial or heterogeneous irradiation depending on the functional organization of the different tissues and the part of the genome that is actively transcribing. In addition, different radiation types have largely varying biological effects depending on their ionization density. Therefore high LET beams irradiating mainly serial tissues like spinal cord constitute the greatest treat for acute and late radiation response. On the opposite end low LET exposer of a tissue with mainly parallel response may be well tolerated since the organ can compensate the loss of function and most of the damage is repairable. This is the reason why low LET radiation beams can be effectively used to cure many tumors. The recently discovered low dose radiation sensitivity is a further example of the complex interaction of radiation damage and the advanced cellular surveillance system. Knowledge about these processes are fundamental both for estimation of the radiation induced morbidity in radiation protection contexts and for estimation of the response of different organs during radiation therapy.

The field of radiation biology is today in a state of rapid development largely because the rapidly increasing body of knowledge in the area of molecular and cellular biology and radiation science. The aim of the present description is to describe some of the main phenomena of human radiation biology and indicate where new information in the coming years may be most influential.

The aim of this lecture is two-fold.

The first part

will be describing the planned third generation neutron sources, which are presently under construction in the US and Japan and being planned in Europe. Special emphasis will be on the required performance of the nuclear part of these sources, and why the next generation intense neutron sources for neutron scattering applications are accelerator driven spallation sources rather than high flux reactors.

The second part

of the lecture will provide an overview of the main features of the spallation phenomenology and will discuss briefly some of the physics aspects of spallation and the nuclear models, known as the so-called INCE (intra-nuclear-cascade-evaporation) process.

A project for an International Fusion Material Irradiation Facility (IFMIF) is being conducted in a joint effort between the European Union, Japan, the USA and the Russian Federation under the auspices of the International Energy Agency (IEA) with the objective to provide the technical basis for an accelerator-based D-Li neutron source for high fluence test irradiations of fusion reactor materials. IFMIF employs two continuous-wave linear accelerators each generating a 125 mA beam of 40 MeV deuterons striking a thick target of flowing liquid lithium to produce high energy neutrons through the Li(d,n) stripping reaction. The available irradiation test volume downstream the lithium target is partitioned into a high flux region (0.5 L, 20-50 dpa/full power year), a medium flux region (6 L, 1-20 dpa/full power year) and a low flux region (> 100L, < 1dpa/full power year). By utilising the small specimen test technology for the material samples in the high flux region, IFMIF is capable of meeting the requirements specified for irradiation tests of candidate fusion reactor materials.

The lecture will outline the IFMIF project, present an overview of the plant design including the accelerator system, lithium target and test facilities, address the question of its suitability as neutron source for irradiation tests of fusion reactor materials and focus on the recent progress in design and development of the IFMIF facility. The lectures concludes with an outlook of IFMIF`s potential role in the long term strategy of fusion technology.

The neutron serves as a unique probe in materials science, including geology, environmental sciences biology, archaeology, and engineering, as well as physics and chemistry. Compared to other techniques, such as X-ray scattering, it has a wavelength and energy comparable to typical atomic spacing and vibrational energies. It is highly penetrating, has a magnetic moment, but no charge, and nuclear diffraction happens only at the nucleus. These advantages justify its use as a privileged probe in spite of the high cost and low intensity of neutron sources. Further on, the research on the neutron itself as a particle provides further knowledge in fundamental physics.

The most intense neutron source in the world is the High Flux Reactor (HFR) at the Institut Laue-Langevin (ILL) in Grenoble. The conception of this reactor source – in contrast to alternative spallation sources, presented before in the frame of the ESS project – will be presented: the core with the different sources (moderators) provide neutrons in different energy ranges. Thermal, hot and cold neutrons are propagating towards the different types of instruments through simple beam tubes or neutron guides. The basics of these guides, of monochromators, choppers, polarisation devices and other elementary elements of neutron optics (collimators) will be discussed.

Diffractometers investigate elastic scattering from solid and liquid matter, revealing details of structure at different scales. At a larger scale, for colloids, polymers and biological samples, using small angle neutron diffraction with cold neutrons, at atomic scale for polycrystalline (powder) or single-crystal solids with two-axis or four-circle diffractometers, working with thermal neutrons, or for short-range order of liquid and amorphous samples with two-axis diffractometers working with hot neutrons. Examples of these investigations of structure and its evolution shall be shown on high temperature superconductors, ion conductors, glasses, polymers, particles under flow, residual stress, cement, bone texture and physisorption.

Inelastic spectrometers examine the energy exchange of neutrons with a sample in different energy ranges, wherefore different instrument types (spin-echo, time-of-flight or triple-axis spectrometers) are needed, working with hot, thermal or cold neutrons. These energy exchanges may be due to phonons or magnetic excitations, e.g.

Instruments examining the neutron particle itself, often needing ultracold neutrons, will be presented briefly. In this classical physical research area falls the neutron detection itself. Different detector types and especially position sensitive neutron detectors as used on most instruments will be explained.

A global strategy for the back-end of the fuel cycle aims at integrating the various issues and impacts (in space and time) associated with nuclear energy production concerning health, environment and resource. There are also other concerns such as proliferation, economical competitiveness and social acceptability. In practice, a global strategy is defined by various technical and industrial options and evaluated according to some criteria such as waste reduction, global nuclear material inventory in the reactors and downstream, natural resources needed.

The two present strategies (reprocessing/mono-recycling) and direct disposal of spent fuels will be first presented and discussed. After having given the basic physical principles and properties (including safety), advanced strategies based on recycling (or transmutation) will be presented. This comprises the different systems involved (fuel types including thorium based, reactor types, reprocessing methods) and the various scenarios describing how these may be implemented in a nuclear reactor pool.

There is international consensus that deep geological disposal is the preferred option for safe management of long-lived high level radioactive waste. Geological disposal is based on the ethical principle that we should not pass undue burdens to coming generations. To meet these requirements the long-term safety of a repository should not be dependent on monitoring and maintenance.

Different geological disposal concepts have been developed and adopted to various waste types and host rocks. The KBS-3 method developed for final disposal of spent nuclear fuel in crystalline rock will be presented as an example. The long-term safety of a KBS-3 type deep repository is based on a system of passive barriers with multiple safety functions, so that the degradation of one barrier does not substantially impair the overall performance of the disposal system. The repository is planned to be situated at a depth of about 500 m in granitic bedrock. From a tunnel system, deposition holes are bored in which copper canisters with spent nuclear fuel are emplaced and surrounded with bentonite clay. The tunnels will be backfilled. Studies have shown that a safe repository for spent nuclear fuel can be constructed in crystalline bedrock, and that "good enough" rock is abundant. The scientific and technical basis for the method has been continuously developed and reported to the regulatory authorities and the Government every third year.

Today, research, development and demonstration in-situ are performed in the Äspö Hard Rock Laboratory at the SE coast of Sweden. Investigation methods, which will later be used to characterise the repository site, are developed and tested at Äspö. The canister, the buffer, the backfill and the rock itself are tested, at great deep and by large-scale experiments. All the important steps to construct a safe repository are covered. In other words, the Äspö Hard Rock Laboratory constitutes a "dress rehearsal" for the Swedish deep repository.

Feasibility studies have been conducted in eight municipalities. These are desk studies to investigate the possibilities to site a respository in the community and the potential effects on society and environment. The siting process has now reached the conclusion of the feasibility study phase. The next phase, the site investigation phase, is aimed at gathering the data needed to site and license the deep repository. Siting of the deep repository requires geoscientific investigations with test drilling on selected sites and more in-depth local studies for establishment of the entire deep disposal system. SKB has now proposed sites in three of these communities for such investigations. The proposal is currently under review by the Government and a decision is expected late this year (2001).

Radioactive wastes arising from nuclear power plants, research centers, industries, universities and medical applications have to be treated (conditioned) due to interim storage or final disposal regulations.

Most of the different countries have developed site specific acceptance criteria.

The conditioning of the different primary wastes has to be performed regarding two aspects:

Volume reduction (to save place and money)

Transferring liquid waste in solid state.

For safe storage, transport or disposal there are two different ways:

Embedding the radioactive waste in a matrix (product quality)

Keeping the radioactive waste in a containment (containment quality).

The immobilization of most waste forms in an inactive matrix aims to prevent emission of radioactive particles by encapsulation and to minimize dose rate during handling.

Treatment technology like super compaction, drying and incineration for volume reduction will be discussed.

For encapsulation different matrices have been used like plastic, bitumen, cement, glass etc.

The lecture will outline the advantages/disadvantages as well as development of new matrices like ceramic and polysiloxane.

To store or dispose the waste, characterization of the radioactive waste is necessary to fulfil the waste acceptance requirements (WAR). WAR will be presented as well as the quality assurance (QA) and quality control (QC) systematic approach.

QA comprises all organizational and technical measures taken to guarantee quality. QC comprises the definition and the checking of administrative and organizational regulations as well as the execution of control measures.

Some remarks will be given to radioactivity release barriers in a disposal site. New separation technologies for reduction of radiotoxicity in a repository will be designed.

The economics of reactor operation involves a good deal of physics inputs and the calculation of the levelised cost of generation involves mathematics that has application to all business activities. An understanding of how to calculate the economics of a large project, such as building and operating a reactor, helps to establish the link between the sometimes abstract physics and measures like economics which chief executives and the like are more likely to be interested in.

The lecture starts with a detailed discussion and explanation of what is meant by cost levelisation and how to calculate a levelised cost. It then derives general formulae that we can apply to the problem of reactor economics. It shows how to calculate the capital, operating and maintenance (O&M), decommissioning and fuel costs. The fuel cost is itself broken down into several sub-components, which are analysed in detail, the aim being to extract the underlying physical dependencies that are difficult to isolate in a conventional cash-flow economic analysis.

The lecture will first address recent surveys on electricity generating costs (OECD-NEA, French General Planning Commission) and will compare the main cost items with those of other energy sources, with a view to discussing the conditions for nuclear power to be competitive (investment, plant operation, fuel cycle, externalities).

The consequences for optimising the operation of existing power plants to remain competitive in a liberalized energy market will then be analysed, with a specific emphasis put on ways to valorise the capital investment (reliability/load factor, lifetime extension), to optimise operating and maintenance costs (risk informed O & M approach), and to increase the fuel performances to reduce fuel cycle costs.

In a third part of the lecture, the general goals assigned to future nuclear energy systems will be reviewed (economics, reliability and safety, sustainability), and some specific design objectives dedicated to improve the economic competitiveness of future nuclear power plants will be analysed. Current approaches to reduce the investment and financial costs of future nuclear power plants will be presented, including standardisation and scaling effects, that led the present generation of large power plants, and simplification and series effect, that favour smaller units with modular reactors. Examples of economics driven designs will be given both for medium/large size power plants as for small/medium modular reactors. Other design trends likely to favour the economic competitiveness of future nuclear energy systems include high temperature for high conversion efficiency and direct conversion cycle for simplicity.

Dual applications of nuclear power such as cogeneration, desalination and hydrogen production will be presented as additional trends to make the use of nuclear power more competitive and to extend its capability to meet the primary energy needs beyond the generation of electricity.

As a conclusion, many aspects addressed in the lecture will support the demonstrations of the assets and potential of further optimisation of nuclear power to remain competitive in a liberalised energy market, and to encompass a wider range of applications to meet societal needs in the future.

At the Schwer-Ionen-Synchrotron (SIS) for relativistic ions at GSI Darmstadt a recoil spectrometer FRS is installed for separation of reaction products. In inverse kinematics the primary reaction products of spallation and fission at energies in the 1 GeV/nucl.-regime became accessible. The data for about 900 different isotopes in the 1 GeV·A Pb on proton reaction are discussed. Moreover fission of ²³⁸U at 1 GeV·A in reactions with Pb-, Be-, and proton-targets was investigated. The different mechanisms to produce neutron rich isotopes are presented. About 130 new fission products and the doubly magic isotope ⁷⁸Ni were discovered.

The first isotope was produced by Irène Joliot-Curie and Frédéric Joliot in 1934. In the second lecture a survey of radioactive isotope discoveries since then is presented. Today all in all about 2600 isotopes were produced. The transuranic elements searched for by Lise Meitner and Otto Hahn, leading to the discovery of nuclear fission by Otto Hahn and Fritz Strassmann in 1938, arrived now at atomic number 112 in 1996. These experiments which started in 1978 at GSI are reviewed in order to demonstrate the link between fundamental and applied science discussed in the first lecture.