• Journal of the Ergonomics Society of Korea
• /
• v.19 no.1
• /
• pp.109-125
• /
• 2000

The purpose of this study was to provide basic data for a more functional torso's pattern by analyzing multidimensional anthropometric measurements and the wearing condition. For the functional torso's pattern drafting, the fitness state of basic torso's patterns(4 types) was compared and evaluated from the cross-sectioned overlap maps by $moir{\acute{e}}$ topography. The results were as follows: 1. According to the measurements of four patterns by using the one-dimensional measurement, the amount of ease in girth item for pattern A was the smallest. The ease of clothes was affected by the position of dart, the amount of dart, and the drafting method. 2. As the results of wearing evaluation by $moir{\acute{e}}$ topography method, pattern B had the largest space length for hip part, pattern A, C and D had the largest space length for bust part. Also, in the all measurement items, pattern A had the smallest amount of ease. The space length for bust and waist part of pattern B was smaller than pattern D, but, for abdomen and hip part of pattern B was larger than pattern D. The space length of pattern C was revealed intermediate for all measurement part. 3. The significant difference of space length of each pattern was shown in all parts except bust part(p<.05). The amount of space was affected by the amount of dart, the characteristics of the somatotype, and the drafting method.

• Journal of the Korean housing association
• /
• v.13 no.5
• /
• pp.31-42
• /
• 2002

This comparative study between Korean and German housings aims at understanding different structural systems in the indoor and outdoor spaces, depending upon the user′s perception of the socio-cultural attributes. The analysis starts with four alternative contrary assumptions, that appear in morphological forms of dwelling; 1) linear distribution vs. areal distribution of residential districts, 2) mirror system vs. comb system in the layout of plot plans 3) organization of front vs. back outdoor spaces and 4) opening vs. closing in the indoor spaces. A clear difference is found between Korean and German samples in view of public and private relationships between indoor and outdoor spaces as well as the intermediate space. In the korean housing there always exists a symbolic and psychological territory of a certain sphere. On the other hand, outdoor space passes through various phases only to form a certain hierarchy even in a private space and, thereby, sets a boundary between private and public areas. In the case of Germany, the building itself draws a clear line between private and public outdoor spaces, and therefore the outdoor space has a "front" and "back". Thus, Germany′s private space may face a genuine public space and street, which is rare in the Korean housing. Although the layout of indoor space in the korean housing tends to be open, such an openness may be outstanding in living and dining spaces, kitchen and various accesses to rooms. In the case of Germany, such indoor spaces are usually closed to each other. Thus corridors act to separate these spaces. Such differences are analysed to be due to the different perceptions of interpersonal and socio-cultural attributes as intra-family and inter-neighbor relationships or communications.

• Proceedings of the KSRS Conference
• /
• 2002.10a
• /
• pp.587-592
• /
• 2002

A new digital correlator fur an airborne synthetic aperture radiometer was designed in order to replace the conventional analog correlator unit which will become very complicated while the number of channels is increasing. The digital correlator uses digital IQ demodulator instead of the intermediate frequency (IF) phase shifter to make the correlation processing performed digitally at base band instead of analogly at IF. This technique has been applied to the digital receiver in softradio. The down-converted IF signals from each pair of receiver channels become low rate base-band digital signals after under-sampled, Digitally Down-Converted (DDC), decimated and filtered by FIR filters. The digital signals are further processed by two digital multipliers (complex correlation), the products are integrated by the integrators and finally the outputs from the integrators compose of the real part and the imaginary part of a sample of the visibility function. This design is tested by comparing the results from digital correlators and that from analog correlators. They are agreed with each other very well. Due to the fact that the digital correlators are realized with the help of Analog-Digital Converter (ADC) chips and the FPGA technology, the realized volume, mass, power consumption and complexity turned out to be greatly reduced compared with that of the analog correlators. Simulations show that the resolution of ADC has an influence on the synthesized antenna patterns, but this can be neglected if more than 2bit is used.

• The Journal of the Acoustical Society of Korea
• /
• v.18 no.1
• /
• pp.10-15
• /
• 1999

We have studied a method to design and fabricate the Intermediate Frequency(IF) band pass filter with low shape factor which is used for CDMA base station on the 35°Y-cut X-propagation Quartz substrate. In order to fabricate a device of the low shape factor for the IF SAW filter on this substrate, we employed apodization weighted type interdigital transducer(IDT) as an input and withdrawal weighted type IDT as an output by using impulse modelling method. Also, using the Kaiser-Bessel window function, we have adopted 2200pairs and 1000pairs of input and oueut IDT respectively to minimize the effect of ripple. Furthermore, the width and the space of IDT finger are 3.6 ㎛ and 3.5 ㎛ respectively. Thus, we can have optimal results when the IDT thickness is 6000Å in consideration of the ratio of SAW's wavelength while it's aperture is 2mm for impedance matching. The fabricated SAW filter for CDMA had the property of almost 115.2MHz of a center frequency, less then 1.27MHz of bandwidth, less than 1.3 of shape factor, - l5dB of out band attenuation insertion loss and -45dB of rejection band.

• Tunnel and Underground Space
• /
• v.26 no.5
• /
• pp.339-347
• /
• 2016

The world's first underground repository for low- and intermediate- level radioactive waste (SFR1) has been in operation since 1988. SFR1 can accommodate $1,000m^3$ of radioactive waste per year with 4 chambers and 1 silo with a total capacity of $63,000m^3$ of radioactive waste. With extended operation time of 10 of the 12 nuclear power reactors and dismantling of the other 2 nuclear reactors, more nuclear waste need to be disposed in the future. Therefore, Swedish Nuclear Fuel and Waste Management Company (SKB) submitted a license application for a repository extension (SFR3) that consists of 6 additional rock chambers with a capacity of $108,000m^3$ of radioactive waste and for accommodating 9 boiling water reactor tanks. In this study, plans for the extension SFR3 are presented with the geological, geomechanical and hydrogeological issues to be considered.

• Journal of Institute of Control, Robotics and Systems
• /
• v.8 no.9
• /
• pp.719-727
• /
• 2002

We proposed a decoupled adaptive fuzzy sliding-mode control scheme for a class of fourth-order nonlinear systems. The system is decoupled into two second-order systems such that each subsystem has a separate control target expressed in terms of sliding surface. For these sliding surfaces, we define main and sub target conditions. and, we made intermediate variables which are interconnected both surface conditions from the sub target sliding surface. Then, Two sets of fuzzy rule bases are utilized to represent the equivalent control input with unknown system functions of the main target sliding surface including intermediate variables. The membership functions of the THEN-part, which is used to construct a suitable equivalent control of sliding-mode control, are changed according to the adaptive law. With such a design scheme, we not only maintain the distribution of membership functions over state space but also reduce the computing time considerably. We apply the decoupled adaptive sliding-mode control to a nonlinear Cart-Pole system and confirms the validity of the proposed approach.

• Bulletin of the Korean Chemical Society
• /
• v.33 no.9
• /
• pp.3025-3032
• /
• 2012

Carbon microcapsules containing silicon nanoparticles (Si NPs)-carbon nanotubes (CNTs) nanocomposite (Si-CNT@C) have been fabricated by a two step polymerization method. Silicon nanoparticles-carbon nanotubes (Si-CNT) nanohybrids were prepared with a wet-type beadsmill method. A polymer, which is easily removable by a thermal treatment (intermediate polymer) was polymerized on the outer surfaces of Si-CNT nanocomposites. Subsequently, another polymer, which can be carbonized by thermal heating (carbon precursor polymer) was incorporated onto the surfaces of pre-existing polymer layer. In this way, polymer precursor spheres containing Si-CNT nanohybrids were produced using a two step polymerization. The intermediate polymer must disappear during carbonization resulting in the formation of an internal free space. The carbon precursor polymer should transform to carbon shell to encapsulate remaining Si-CNT nanocomposites. Therefore, hollow carbon microcapsules containing Si-CNT nanocomposites could be obtained (Si-CNT@C). The successful fabrication was confirmed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). These final materials were employed for anode performance improvement in lithium ion battery. The cyclic performances of these Si-CNT@C microcapsules were measured with a lithium battery half cell tests.

• Geomechanics and Engineering
• /
• v.7 no.3
• /
• pp.317-333
• /
• 2014

The study of the mechanical behavior of rockfill materials under three-dimensional loading conditions is a current research focus area. This paper presents a microscale numerical study of rockfill deformation and strength characteristics using the Combined Finite-Discrete Element Method (FDEM). Two features unique to this study are the consideration of irregular particle shapes and particle crushability. A polydisperse assembly of irregular polyhedra was prepared to reproduce the mechanical behavior of rockfill materials subjected to axial compression at a constant mean stress for a range of intermediate principal stress ratios in the interval [0, 1]. The simulation results, including the stress-strain characteristics, relationship between principal strains, and principal deviator strains are discussed. The stress-dilatancy behavior is described using a linear dilatancy equation with its material constants varying with the intermediate principal stress ratio. The failure surface in the principal stress space and its traces in the deviatoric and meridian plane are also presented. The modified Lade-Duncan criterion most closely describes the stress points at failure.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.29 no.1 s.232
• /
• pp.123-130
• /
• 2005

A digital in-line holographic particle image velocimetry (HPIV) which can be applied to measure three-dimensional velocity fields of turbulent flows was developed. There are three different implementation methods of HPIV: traditional film-based HPIV, intermediate HPIV and digital HPIV. The traditional film-based HPIV and intermediate HPIV method is rather troublesome to do experiments and takes long calculation time, compared with the digital HPIV, Configuration of the digital in-line HPIV is simple and the data processing routine is similar to conventional 2D PIV methods. The digital HPIV velocity field measurement consists of four steps: recording, numerical reconstruction, particle extraction and velocity extraction. In the velocity extraction process, we improved PTV algorithm to extract the displacement of particle each placed in 3D space. The developed digital in-line HPIV system was applied to a vertical jet flow. The 3D velocity vectors measured by the digital HPIV method in the near field are in a good agreement with 2D PIV results.

• Journal of Agricultural Extension & Community Development
• /
• v.25 no.3
• /
• pp.161-173
• /
• 2018

The study aims to explore the policy directions for young farmers within Korean agricultural context, particularly in Chung-nam Province. In order to accomplish this, young farmers were classified into three categories: successors, new farmers, potential farmers. The importance of young farmers is becoming more of a focus due to decline of population numbers in rural communities as well as the aging of agriculture population. In order to address these two problems, it is necessary to create and implement policy to support each category of young farmer. Rather than the current focus on nurturing young farmers as a labor force, the role of young farmers in maintaining local communities should be expanded in current agricultural system. The local community should provide appropriate conditions for young farmers in Chung-nam Province for the various purposes they have and the roles they fill. In conclusion, it is necessary to provide a 'space' where young farmers can meet base on the community. For this, the role of the community based intermediate support organization for the integrated support system is of great significance.