• The Korean Journal of Food And Nutrition
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• v.13 no.1
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• pp.21-27
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• 2000

In order to investigate the changes of rice qualities during 4 years storage of paddy in warehouse of normal temperature condition. As storage period go by, head ratio was deduced and broken rice was increased according as a change of temperature during the long term storage. A color of rice was became more dark gray than that of entering time as L value was decreased from 64.07 to 61.62 a 4 years late. As a results of studies on the cooking quality of milled rice, water uptake ratio and expanded volume were increased in proporation to storage period, wherease total solids and iodine blue value were decreased. In the characteristic of texture of cooked rice, viscosity/hardness ratio(-H/H) had a decreasing tendency, while adhesiveness and cohesiveness increased with increased storage time. The qualities of cooked milled rice studied were sensory attributies of odor, taste, stickiness and appearance which were evaluvated by multiple comparsion method. The sensory results showed that all of descriptions were deterirated with a increased storage period. The taste and stickiness were changed from good score to bad score a 2 years later.

• Journal of the Korean housing association
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• v.24 no.6
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• pp.33-40
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• 2013

Hiroshi Hara is one of the most famous architect in the history of contemporary Japanese architecture. During the 1970's beginning with the Awazu Residence (1972), he designed a series of symmetrical houses, the so called 'Reflection House'. All the houses in this period were based on the method of 'reflection' and 'inversion', which means a radical reversal of the accepted notion that houses are parts of cities. A concept of "A house within a house" is expanded to "A city within a house". The important spatial characteristics of 'Reflection House' are main internal core and valley-like spaces forming internal urban streets by bringing natural elements and the components of streetscape such as plaza, open space, context of street facades and so on. This procedure is called as embedding 'city' into 'house', Hara mentioned. This paper investigates the outline of the 'Reflection House' and analyses the completed works of housing that were based on the theory. Then in the final part of the paper, the implications of 'Reflection House' and its influence on his later works of following period will be discussed.

• KIEAE Journal
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• v.16 no.6
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• pp.5-12
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• 2016

Purpose: Quasi-steady state simulations have played a pivoting role to expand the user group of simulation to design engineers and architects in Korea. Initially they are introduced in the market as a building energy performance rating tool. In domestic practice, however, quasi-steady state simulations seem to be regarded as a de facto simulation only available for energy retrofit. Selection of ECMs and economic feasibility analysis are being decided through these tools, which implies that running these tools has become a norm step of the Investment-grade Audit. Method: This study aims at identifying issues and problems with the current practice via test cases, analyzing the reasons and opportunities, and then eventually suggesting proper uses of quasi-steady state and dynamic simulations. Result: The functionality of quasi-steady state simulations is more optimized to the rating. If they are to used for energy retrofits, their off-the-shelf functions also need to be expanded for customization and detailed reports. Yet their roles may be limited only to the go/no go decision; because their algorithms are still weak at precisely estimating energy and load savings that are required for making investment decisions compared to detailed simulations.

• The Journal of the Convergence on Culture Technology
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• v.2 no.4
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• pp.49-54
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• 2016

Development of AR/VR has expanded computer games from indoor static contents to outdoor dynamic contents. The syndrome of 'Pokemon Go' which is a representative AR game was born, and Nintendo's stock price shot up a massive 120%. Although some people gained profits, new damages are emerging including illegal intrusion or road accidents because it is a type of game to visit real locations. There are reported about 114 thousand road accidents related to the game. This study aims to examine the trends of AR game in 2016 and analyze damages and positive cases to suggest a method for preventing accidents due to the AR game, and a business model.

• Journal of the Korean Institute of Telematics and Electronics
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• v.18 no.1
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• pp.16-24
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• 1981

The delay-lock loop (DLL) is a statistically optimum device for tracking the de]ay difference between two correlated waveforms. In this paper an extended n - $\Delta$ (n=1,2,3‥‥) DLL is described, and its baseband performance including the frequency to lose lock is analyzed. The present DLL system employs a correlator and a pseudonoise sequence synthesizer that has been improved from the previously used ones The shape of the correlator characterigtic has the form of expanded S-curve. Despite of increase noise, this extended DLL has desirable characteristics in tracking range and initial synchronization time. Comparing a 3 - $\Delta$ DLL with a 1 - A DLL, the former Bives three times faster initial synchronization time with the serial synchronization method, and gives two times immunity against doppler shift.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.1
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• pp.101-106
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• 2012

The press bulging process is very useful and productive method to produce round-type mechanical components which have not been able to be manufactured because of limitation of the conventional press technology. The application of the press bulging process has expanded very quickly in the hydraulic and electronic industry and more recently it has been used to produce other mechanical parts such as the automobile and shipping parts. This expanding application also has brought some unsolved problems and leads many researchers to put their effort into the die design of the press bulging process. In this study, to obtain the optimum die shape for the press bulging process, various process parameters have been considered such as corner radius, bulging height, pressing length, and forming load, etc. The main interest of this paper is to verify the press bulging process which has more than 4.0 in height-length ratio. From this aspect, Finite Element analysis shows great ability to simulate the precise deformation process and gives us manufacturing database. Consideration of strain, stress, and strain-rate for the various cases has been also taken to keep the forming load within a particular range.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.10
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• pp.1240-1247
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• 1999

Particle motion through a disk type critical orifice placed in a 3.0cm diameter chamber has been studied numerically. In the simulation, the velocity field is solved using Pantankar's SIMPLER algorithm for the compressible flow and convergence of the computation is confirmed if the mass source at each control volume is smaller than $10^{-7}$. The particle motion in the flow field is solved in Lagrangian method. The particle trajectories showed that the particles injected away from the center line are expanded rapidly. At lower pressures, this expansion phenomena are more dominant. At lower pressures, the clear difference in particle and air speed is showed all the way down to the exit plan. It was found that particles with Stokes number of ca.2.5 tend to focus close to the center line very well except the particles travelling near the wall. However, particles with Stokes number greater than ca.2.5 show a tendency to cross the center line.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.6
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• pp.837-844
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• 2001

Jet cutting technology currently makes use of a generic supersonic gas jet to improve the cutting speed and performance. In order to get a better understanding of the flow characteristics involved in the supersonic jet cutting technology, the axisymmetric Navier-Stokes equations have been solved using a fully implicit finite volume method. Computations have been conducted to investigate some major characteristics of supersonic coaxial turbulent jets. An assistant gas jet has been imposed on the primary gas jet to simulate realistic jet cutting circumstance. The pressure and the temperature ratios of the primary and assistant gas jets are altered to investigate the major characteristics of the coaxial jets. The total pressure and Mach number distributions, shock wave systems, and the jet core length which characterize the coaxial jet flows are strongly affected by the pressure ratio, but not significantly dependent on the total temperature ratio. The assistant gas jet greatly affects the basic flow characteristics of the shock system and the core length of under and over-expanded jets.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.7
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• pp.915-922
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• 2004

A stent is small tube-like structure expanded into stenotic arteries to restore blood flow. The stent expansion behaviors define the effectiveness of the surgical operation. In this paper, finite-element method was employed to analyze expansion behaviors and fatigue life of a typical diamond-shaped balloon-expandable stent. Beyond safety considerations, this type of analysis provides mechanical properties that are often difficult to obtain by experiments. Mechanical properties of the stent expansion pressure, radial recoil, longitudinal recoil and foreshortening were simulated using commercial FEM code, ANSYS and fatigue life were estimated using NISAII ENDURE. The FEM results showed that the pressures necessary to expand the stent up to a diameter of 3mm, 4mm and 5mm were 0.75MPa, 0.82MPa and 0.97MPa. The fatigue lifes according to expansion diameter were 114${\times}$10$^{7}$cycles, 714${\times}$$^{6}$cycles and 163${\times}$10$^{6}$cycles. As a result, a finite element model used in this study can simulate expansion behaviors of stents and should be useful to design new stents or analyze actual stents.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.11
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• pp.863-869
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• 2008

This paper investigated the new calibration algorithm of a straight-type five-hole pressure probe for measuring three-dimensional flow velocity components. This new calibration algorithm was used for velocity data reduction from the calibration map and based on the combination of a look-up, a binary search algorithm and a geometry transformation including the translation and reflection of nodes in a calibration map. The calibration map was expanded up to the application angle, ${\pm}55^{\circ}$ of a probe. This velocity data reduction method showed a perfect performance without any kind of interpolating errors in calculating yaw and pitch angles from the calibration map. Moreover, when it was applied to an actual flow field including a swirling flow, a good result came out on the whole.