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The KSTAR components requiring cryogenic helium coolant for superconducting magnet operations are connected to the helium refrigeration system (HRS) through the helium distribution system (HDS), the final helium distribution station. Twenty eight cryogenic valves including 4 quench protecting valves, many sensors such as temperature sensors, pressure transmitters, and flowmeters are mounted on the system. The HDS has to control the 4.5 K supercritical helium (600 g/s) for 30 superconducting coils and their superconducting bus-lines, 55 K helium (270 g/s) pressurized to 18 bars for the thermal shields and the gravity supports, and a maximum 17.5 g/s of liquid helium for 18 current leads, provided from the HRS which has a 4.5 K equivalent cooling power of 9 kW. The helium distribution system consists of a helium distribution box (DB), 5 helium transfer lines, a PLC based helium control system (HCS), etc. The helium control system is connected to the KSTAR supervisory control & interlock system. The detailed status regarding the construction, commissioning during first cool-down, and the instrumentation & control (I&C) system are included in this paper.

Odor is one of the major nuisances in the environment. In most countries, odor annoyance from livestock production is an increasing problem in community. In order to reduce the odor inconvenience and establish a good relation between livestock industries and the surrounding communities, many studies, such as diffusion simulations and field experiments, on the odor dispersion and its reduction have been investigated. These studies need to accompany the aerodynamic approach, as a main mechanism of diffusion phenomenon, and computational fluid dynamics(CFD) can be effectively used to study this kind of research. CFD considers both various wind conditions as well as topographical conditions to study aerodynamic phenomenon. Therefore the ultimate objective of the study was to develop an aerodynamic model to predict qualitatively and quantitatively odor diffusion from livestock. In this study, as the first step of this study, various phenomena and factors of odor diffusion from livestock houses were investigated through field experiments in 2007. Later, those data will be also used to verify the CFD accuracy as well as to develop 3-dimensional CFD model.

Most of the broiler houses in Korea have experienced problems on controlling the environmental conditions such as suitability, stability and uniformity of rearing condition inside the broiler house. It is very critical which if not properly controlled, would cause serious stress on the chickens. It is therefore urgent to develop optimum designs of naturally ventilated broiler house which is appropriate to the four seasons of Korea. Field experiment for this matter is very difficult to conduct due to the unpredictable and uncontrollable weather condition. In this study, the heating load of a naturally ventilated broiler house was calculated using TRANSYS 15 BES program while internal climate and thermal condition were computed using Fluent 6.2. The computed resulted of the conventional ventilation system (A) and upgraded ventilation system (B) (Seo et al, 2007) were compared with each other for cold season. The results of the Building Energy Simulation(BES) indicated that the system B, the upgraded ventilation system made 8% lower total heating load and 47% lower at only the broiler zone compared to the conventional broiler house. Considering the entire broiler house, the existence of middle ceiling made the heating energy 11% lower required than without middle ceiling. Accordingly, the system B with middle ceiling was found to save heating energy by 20% in average. This study showed that the BES program can be a very powerful to effectively compute the energy loads of agricultural building while the energy load is very close related to ventilation efficiency.

The extensive design effort for KSTAR has been focused on two major aspects of the KSTAR project mission - steady-state-operation capability and advanced tokamak physics. The steady state aspect of the mission is reflected in the choice of superconducting magnets, provision of actively cooled in-vessel components, and long pulse current drive and heating systems. The advanced tokamak aspect of the mission is incorporated in the design features associated with flexible plasma shaping, double null divertor and passive stabilizers, internal control coils and a comprehensive set of diagnostics. Substantial progress in engineering has been made on superconducting magnets, the vacuum vessel, plasma facing components and power supplies. The new KSTAR experimental facility with cryogenic system and deionized water cooling and main power systems has been designed, and the construction work is under way for completion in 2004.

The Korea Superconducting Tokamak Advanced Research (KSTAR) project is the major effort of the national fusion programme of the Republic of Korea. Its aim is to develop a steady state capable advanced superconducting tokamak to establish a scientific and technological basis for an attractive fusion reactor. The major parameters of the tokamak are: major radius 1.8 m, minor radius 0.5 m, toroidal field 3.5 T and plasma current 2 MA, with a strongly shaped plasma cross-section and double null divertor. The initial pulse length provided by the poloidal magnet system is 20 s, but the pulse length can be increased to 300 s through non-inductive current drive. The plasma heating and current drive system consists of neutral beams, ion cyclotron waves, lower hybrid waves and electron cyclotron waves for flexible profile control in advanced tokamak operating modes. A comprehensive set of diagnostics is planned for plasma control, performance evaluation and physics understanding. The project has completed its conceptual design and moved to the engineering design and construction phase. The target date for the first plasma is 2002.

Styrene (ST or 1) and maleic anhydride (MA or 0) were copolymerized in carbon tetrachloride (CCl 4 ) and in N,N-dimethylformamide (DMF) with a wide range of MA mole fraction in the feed (f 0 = 0.01 to 0.90) at 50°C. The DEPT 13 C NMR subspectra of methylene carbon of ST(I) units were used to determine the ST(I) centered triad mole fractions (F 010 , F (011 + 110) +F 111 ). Non-linear least squares (NLLS) curve fitting was used to fit the theoretical equations of the five copolymerization models, namely, the (1) terminal, (2) penultimate unit effect, (3) complex participation, (4) complex dissociation and (5) comppen models, to these experimental data in order to calculate the sum of squares (SS) and the reactivity ratios. The complex participation model is indicated as the model providing the best fit by the smallest SS values calculated from F 010 data and by the variation pattern of the test functions a and b for both copolymerization systems. The F test for SS of F 010 data can only show an improvement of fit of the complex participation model over the penultimate unit effect model with less than 90% probability confidence for the MA + ST/CCl 4 system and with 97.5% probability confidence for the MA + ST/ DMF system. This is consistent with the result obtained from the order grade matrix method reported previously.

The construction of ITER is an extremely important project, not only within the fusion society but also for mankind: By solving critical energy and environmental problems, another major step in human history will be taken. Design, construction, and assembly of an ultra large scale machine such as ITER require thoroughly well defined plans, strategies, and predictions of potential problems and solutions. It is believed that preceding devices and projects may provide useful references for the several important considerations noted above. The KSTAR (Korea Superconducting Tokamak Advanced Research), a representative superconducting tokamak, has the most similar characteristics to the design concept of the ITER. Therefore, the lessons learned from KSTAR can be categorized according to the following engineering aspects: 1) policies to prioritize decisions, 2) catch-up plans for delayed schedules, 3) strategies in site assembly, 4) troubleshooting, 5) standard indexes or guides for tests and acceptance of individual systems and of site assemblies, and 6) interfaces that can be easily omitted in view of the system integration. This paper will summarize the lessons we have learned from the KSTAR project, focusing on engineering related points that can be considered to suggest guidelines for the ITER construction.