Certification criteria in type I ecolabelling related to metals for sustainable materials management

A sustainable materials management for metals should be achieved to conserve resources of metal minerals. For the sustainable materials management, material flows through the whole life cycle of materials have been recognized by material flow analysis (MFA) studies. Former MFA studies pointed out that cyclic use of metals could be enhanced not only by increasing quantity of recovered scrap but also by upgrading quality of the scrap. In general, the quality is degraded by contaminants which commingle at disassembling processes. The mixture of contaminants depends on usage of materials in products. Here, Type I ecolabelling has a potential to convey messages for avoiding mixture of contaminants to the producers of finished products. In this study, on the basis of a survey on existing certification criteria related to metals in the world, a general concept of certification criteria on sustainable materials management for metals in Type I ecolabelling system is proposed. Finally, we propose six criteria in the form of certification criteria in Type I ecolabelling system.     

高压喷射搅拌工法改良体形成之实际状态与评价方法

属于高压喷射搅拌工法中一种之喷射灌浆工法(以下简称「JG 工法」),于地层结构复杂之地质条件下,因地质软硬差异造成有效桩径不同,故对于设计或施工管理值标准之采用为一尚待检讨之课题.即针对该等JG工法之技术性问题,根据大范围开挖改良体内部之施工案例所获得之观察结果提出报告.由改良体内部之观察结果可知,若无流木等障碍物之存在,先行灌浆形成之改良体各水平断面大致呈圆形,且后行灌浆形成之改良体与先行灌浆改良体之间呈密合状态.此外亦针对将改良体整体性列入考虑之强度,提出新的评价方法.     

On the dispersion relation of hydroelastic waves in a plate

This paper deals with the dispersion relation of hydroelastic waves in pontoon-type very large floating structures (VLFS) using a simple beam modeling, where the term hydroelastic waves means propagation of deflection vibrations in VLFS. The purpose of this paper is to show the properties of the hydroelastic waves. The dispersion relation of hydroelastic waves propagating in an infinite plate floating on the water is derived based on the linear water wave theory. The effects of the water depth and of the bending rigidity of the floating plate on the wavelength, phase velocity, and group velocity of the hydroelastic waves are shown theoretically or numerically. Then, the dispersion relation of hydroelastic waves in a finite plate floating on shallow water is investigated. It is shown that the wavelength or the phase velocity of the hydroelastic waves varies with the location in the plate. Received for publication on April 7, 1999; accepted on Aug. 20, 1999     

Frictional drag reduction with air lubricant over a super-water-repellent surface

This paper presents a new technique for reducing frictional drag using a super-water-repellent surface and air-injection (called an SWR & A technique). Its effectiveness was examined by carrying out pressure-loss measurements with a tube of rectangular cross section, along with resistance tests on a horizontal flat plate, a 7.2-m-long tanker model, and a 12-m-long high length-to-beam-ratio model ship. These test results showed that the new technique can significantly reduce the models' frictional drag; for example, the frictional resistance on the SWR surface was reduced by 80% at a speed of 4 m/s and 55% at 8 m/s. Received: October 16, 2000 / Accepted: December 4, 2000     

Optimum routing of a sailing wind farm

To acquire the wind energy of the oceans, a sailing wind farm has been proposed. The wind farm considered is composed of a semisubmersible floating structure, 11 windmills, four sails, six thrusters, and storage for hydrogen. To maximize the acquired energy, an effective algorithm to search for optimum routes was developed. The algorithm is based on the fact that beam winds yield a maximum of acquired energy. This feature reduces the computation time, and, consequently, efficient route optimization becomes possible in a reasonable time. After setting an operational area for the wind farm, navigation simulations for a 1-year period were carried out. A numerical weather forecast was used as well as the responses of the floating structure, such as the speed of the structure, the output power of the windmills, and the time of course changes. In the simulation, the wind farm evades rough seas to avoid structural damage, and an optimum route is searched for. The capacity factor of the system was used to evaluate the efficiency of the optimized routes. From the simulations, the maximum capacity factor achieved was 42.6%. The dependency of the capacity factor on the initial position of the wind farm was also examined. It was shown that offshore from Sanriku in northeastern Japan is an area suited to the operation of the wind farm. The effect of the initial position on consecutive periods of operation is discussed.     

AUV navigation around jacket structures II: map based path-planning and guidance

This paper proposes a path-planning and guidance strategy for an autonomous underwater vehicle (AUV) to perform detailed inspections of jacket structures such as the support legs of offshore platforms. Inspections of such structures are important for maintenance, security, and environmental assessment. These tasks can be carried out at a less cost by using AUVs than through conventional methods. The path-planning method generates a set of waypoints to facilitate the complete coverage of the surface of the target from a constant distance based on the given information about the configurations of both the target and the vehicle. The guidance method actually controls the vehicle such that it follows the waypoints, under the assumption that the position and attitude of the vehicle are being estimated in real time with adequate accuracy. By combining these methods with the localization method we had previously proposed (Maki et al., J Mar Sci Technol [1]) an AUV can perform a fully autonomous observation of jacket structures with prior knowledge of only their configuration. The performance of the method was verified though tank experiments using the AUV Tri-Dog 1. A simple model of a jacket was installed in a test tank, and the vehicle succeeded in inspecting the target.     

GIS-aided prediction for sea-ice distribution

A method of applying the geographic information system (GIS) to predict sea-ice distribution is proposed. The prediction computations are performed using the distributed mass/discrete floe (DMDF) model. The GIS is used to prepare the initial data for the DMDF model, and to display the simulation results together with a digital map and observational data for evaluation and further use. Two areas in the Arctic Ocean were selected to test the computations in this study. The results of the case studies show that this method can help with (1) free-area and free-scale prediction fitting for various purposes, (2) a high-resolution output to provide more detailed data, and (3) a reasonable combination of different data sets to make the best use of the information obtained. The results also suggest that the DMDF model is a good simulation of the ice motion not only for large-scale but also for local-scale predictions. Received: March 19, 2002 / Accepted: June 20, 2002 Acknowledgments. This study was financially supported by the Japan Science and Technology Corporation. The SSM/I sea-ice data were obtained from the EOSDIS NSIDC Distributed Active Archive Center (NSIDC DAAC), University of Colorado at Boulder. The authors thank the persons concerned. Address correspondence to: H. Yamaguchi (yama@fluidlab.naoe.t.u-tokyo.ac.jp)     

早期胃癌临床病理形态与性别的关系

对比了不同性别早期胃癌临床病理形态间的差异。女性多位于胃中1／3处（43.6％），组织类型以印戒细胞癌及低分化腺癌为主（58．1％）；男性多位于胃下1／3处（45．4％），组织类型以分化型管状腺癌为主（51．5％）。粘膜下癌女性淋巴管浸润及淋巴结转移率均高于男性（P＜0．05）。且出现年龄较男性提前。但组织类型在胃内分布无性别差异。术后10年生存率也无差异。     

Time-domain strip method with memory-effect function considering the body nonlinearity of ships in large waves

A time-domain strip method with memory-effect function considering body nonlinearity is presented. In small waves, results from conventional linear strip theory and the present method for a modified Wigley model were compared with the results of linear theories and with experiments, and they were found to be in good agreement. In large waves, a 716 TEU containership was used to compare time histories of motions and vertical bending moments calculated using the present method with experimental results. The time histories of motion were not strongly distorted, but those of the vertical bending moments were extremely distorted, especially for the fore part, and were far from sinusoidal signals. The time histories of the calculations and the experimental results were found to be, qualitatively and quantitatively, in good agreement. A post-Panamax containership was also used as an example of an up-to-date large bow-flare ship, and the calculated results were also found to be in good agreement with the experimental results.