The PRIDE scale mechanical decladder is decladding apparatus for separating and recovering fuel material and cladding hull by horizontally slitting rod-cut. In order to enhance mechanical decladdng efficiency, the main requirements were considered as follows. Decladding of the fuel rods may be performed by rotation of three circular cutting blades inserted among the rollers arranged at 120° portion. In a mechanical decladder, a slitting assembly as a unit for slitting the cladding tube may include cutting blades for slitting and rollers for guiding extrusion of the cladding tube. Rotation of the cutting blades may be caused by the fuel rods being extruded from a plurality of rollers. Slitting intervals of rod-cuts having different diameters may be controlled by adding or removing a spacing plate between the cutting blade and a ranch bolt for fixing the slitting blade to the slitting assembly. An extrusion velocity with respect to the fuel rods may be controlled by a hydraulic pressure applied to the fuel rods. A force for cutting the fuel rods may be adjusted by controlling steel plates. Forces applied to a plurality of rollers may be generated by the hydraulic cylinder. The hydraulic pressure may be controlled by hydraulic pressure controller. The PRIDE scale mechanical decladder mainly consists of auto feeding module, hydraulic cylinder module and blade module. A load cell was installed between the hydraulic cylinder and the extrusion pin to measure the decladding force and slitting velocity, and a data acquisition system capable of obtaining data by using the RSC 232 was constructed. Also, the control panel can control the forward and backward movement of the extrusion pin, the hydraulic flow rate, and the hydraulic velocity. In the mechanical decladding test, 40 pieces of simulated rod-cuts were loaded in two auto feeding basket and slit by utilizing the 3-CUT blade modules in the housing, and hulls and simulated pellets were collected in the collection container. As a result, 80 pieces of simulated rodcut (brass pellets + Zry4 tube) were slit continuously without any problem. About 35 min was required to slit 80 rod-cuts and average decladding force was 260 kg. The decladding force of the ceramic simulated rod-cuts (castable) requires 25 kg less force than the brass pellets. Therefore, it is estimated that the spent fuel rod-cut can be fully split into three pieces using the mechanical decladder.
The GMT-Consortium Large Earth Finder (G-CLEF) is the first instrument for the Giant Magellan Telescope (GMT). G-CLEF is a fiber feed, optical band echelle spectrograph that is capable of extremely precise radial velocity measurement. G-CLEF Flexure Control Camera (FCC) is included as a part in G-CLEF Front End Assembly (GCFEA), which monitors the field images focused on a fiber mirror to control the flexure and the focus errors within GCFEA. FCC consists of an optical bench on which five optical components are installed. The order of the optical train is: a collimator, neutral density filters, a focus analyzer, a reimager and a detector (Andor iKon-L 936 CCD camera). The collimator consists of a triplet lens and receives the beam reflected by a fiber mirror. The neutral density filters make it possible a broad range star brightness as a target or a guide. The focus analyzer is used to measure a focus offset. The reimager focuses the beam from the collimator onto the CCD detector focal plane. The detector module includes a linear translator and a field de-rotator. We performed thermoelastic stress analysis for lenses and their mounts to confirm the physical safety of the lens materials. We also conducted the global structure analysis for various gravitational orientations to verify the image stability requirement during the operation of the telescope and the instrument. In this article, we present the opto-mechanical detailed design of G-CLEF FCC and describe the consequence of the numerical finite element analyses for the design.
Domestic dust remover began to be manufactured and installed in the late 1980s by introducing Japanese products and technologies. Currently, the design standards of dust remover are applied to Japan's design standards and partly sub-unit technology was developed for the domestic environment, but no technology was not developed. In addition, most of the manufacturers are small or small, so many of them have been installed and operated for 25 years because they develop small technologies such as parts deformation and functional addition rather than core technology development. Mechanical dust remover require about 70% of manufacturing costs compared to conventional hydraulic dust remover, which can reduce initial production costs, reduce maintenance costs due to low failure rates, and can be operated reliably. Existing hydraulic dust remover had a problem of contaminating rivers due to leakage of hydraulic oil, but mechanical dust remover have no factors that cause water pollution. Therefore, this study developed a rack-type operating structure for optimal and new construction by developing a multi-stage rack structure of mechanical decontamination components, which are substitutes of conventional rotary and hydraulic dust remover.
위험유해물질(HNS, Hazardous and Noxious Substances)은 해상운송 과정에서 다양한 사고에 노출되어 있어 많은 양이 바다에 유출 될 우려가 있다. HNS 유출에 따른 해양환경의 손상은 유류 유출에 의한 손상보다도 훨씬 큰 것으로 알려져 있다. 특히 해저로 침강하여 침적되는 HNS는 해저생태계에 돌이키기 어려운 피해를 주게 되므로, 반드시 회수되어야 한다. 해저로부터 HNS를 회수하기 위해서는 해저침적 HNS에 대한 정확한 탐지, 안정화 처리 및 회수를 위한 절차와 장비가 필요하다. 그 중에서도 기계적 회수장치를 개발하기 위해서는 성능지표를 이용하여 성능요건을 선정하고, 이를 토대로 기계적 회수장치에 대한 개념설계가 이루어져야 한다. 따라서 본 연구에서는 해저침적 HNS의 회수 절차에서 요구되는 기계적 회수장치에 대한 개념설계안을 제시하였다. 개념설계안으로 해저침적 HNS를 회수하기 위한 기본 시나리오를 제시하고, 자체적 밀폐 성능을 가지는 흡인 기초를 활용하는 방안을 채택하였다. 기계적 회수장치는 흡인 기초, 오 염 방지, 펌프 시스템, 제어 시스템, 모니터링 장비, 위치정보 장비, 이송 장비, 탱크로 구성된다. 이러한 개념설계안은 기계적 회수장치의 부품 및 형상을 결정하는 기본설계에 반영되어 활용될 것으로 기대된다.
As energy consumption of building and the reduction of carbon dioxide emissions have been emphasized, phase change materials(PCM) have been introduced as building materials due to its high heat storage performance. Using shape-stabilizing technique, octadecane/xGnP shape-stabilized PCM(SSPCM) can prevent leakage and improve heat storage performance. The objectives of this study are to propose mix design method of concrete mixed with SSPCM and to evaluate mechanical behaviors of the concrete mixed with SSPCM manufactured according to the proposed mix design. Based on the previously reported material test result, the existing mix design of plain concrete(Concrete standard specification, 2009) is modified to consider reduction of strength in concrete due to the addition of SSPCM. To verify the proposed mix design, specimens are fabricated according to the proposed mix design and axial strength tests and three-point loading tests are performed. Test results show that compressive strengths of the tested specimens reach the designed strength even when two different mix ratios of SSPCM are used. From three-point loading tests, flexural stresses decrease as mix ratio of SSPCM increases.
This paper is concerned with the mechanical design of hyperbaric oxygen chamber for multi-users using stress analysis. HBOT(Hyperbaric Oxygen Therapy) is very effective medical equipment for increasing the concentration of melted oxygen in human and animal body. The hyperbaric oxygen supplies to the impaired cell of human and animal to recover the healthy condition. This research reported the design specifications and mechanical safety of hyperbaric oxygen chamber using computational stress analysis with CATIA program. The result from this research can be used for making the practical HBOT equipment for multi-users and to manufacture the real model
The design composition elements and the mechanical behavior of trusses have been investigated for Pratt trusses. As a result, it was determined that the design composition elements of the trusses consist of the composition of webs, the distance between joints, the chords profile, the depth of the truss, and the double chord composition. In addition, by analyzing models with a variation of elements, comprehensive features of structural behavior have been presented for variations of design of Pratt trusses. This is to provide more effective and useful design information on truss structure in the architectural and structural planning stage.
KASI (Korea Astronomy and Space Science Institute) is developing the near-infrared camera system named KASINICS (KASI Near-Infrared Camera System) which will be installed at the 60cm f/13.5 Ritchey-Chretien telescope of the Sobaeksan Optical Astronomy Observatory (SOAO). The camera system is optimized for JHKL bands and has a 6 arcmin FOV. The optical system consists of two spherical mirrors and a 8-position filter wheel. With the exception for the dewar window, all optical elements are cooled inside cryogenic dewar. Since the Offner system is adopted to prevent thermal noises from outside of the telescope primary mirror, the secondary mirror of the Offner system acts as a cold Lyot stop. The optical performance does not change by temperature variations because the Aluminum mirrors contract and expand homogeneously with its mount. We finished the design and fabrication of the optical parts and are now aligning the optical system. We plan to have a test observation on 2006 January.