• 한국멀티미디어학회논문지
• /
• 제6권1호
• /
• pp.15-27
• /
• 2003

Recently, the volume of data is increasing rapidly in server for multimedia service, according to development of multimedia application environment. In recent research for storage technology the technology like of the SAN(Storage Area Network) advantages in scalibility of storage devices, and can read data from multiple disk arrays through RAID 0, 5. The RAID 0 and 5 translate to logical address to physical address using equation, but in case of adding disks at the system with equation -based mapping, the problem that we must rearrange the whole data in the previous disks happens. We use the mapping table to solve this problem in recent, but we can not load the whole mapping table in main memory because it occupies too large space. Therefore the extra I/Os are demanded to evaluate real physical address of data, so total performance of the system is degraded. In this paper, we propose the mapping method that supports the scalibility in RAID 0 or 5 system. The proposing method applies small metadata, so- called SZIT and simple equation, so it is possible that we make translate logical address to physical address rapidly and it is scalable in disk extending simultaneously Our suggesting method, if we add disks to the striping system for expanding of storage capacity, has an advantage of never stop service. So, SZlT-based mapping method can do online-disk-expanding in real-time service.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2005년도 ICCAS
• /
• pp.1260-1263
• /
• 2005

Data storage related with writing and retrieving requires high storage capacity, fast transfer rate and less access time. Today any data storage system cannot satisfy these conditions, however holographic data storage system can perform faster data transfer rate because it is a page oriented memory system using volume hologram in writing and retrieving data. System can be constructed without mechanical actuating part therefore fast data transfer rate and high storage capacity about 1Tb/cm3 can be realized. In this research, to reduce errors of binary data stored in holographic data storage system, a new method for bit error reduction is suggested. First, find fuzzy rule using experimental system for Element of Holographic Digital Data System. Second, make fuzzy rule table using Genetic algorithm. Third, reduce prior error element and recording Digital Data. Recording ratio and reconstruction ratio will be very good performance

• 한국주거학회:학술대회논문집
• /
• 한국주거학회 2009년 춘계학술발표대회 논문집
• /
• pp.304-309
• /
• 2009

The purpose of this study is to develop kitchen furniture design for 40-pyung apartment Houses based on stored item of Cooking, Eating and Utility Area. The research data is gotten at a field study of stored items of Cooking, Eating and Utility Area and depth interview. The results of this study were as follows; 1)The kitchen furniture the preparation unit and the sink, the kitchen table, the heating unit and the service table, arranged at the tall storage. 2)The total bulk considered and holding volume ($2.7m^3$) with ground clearance (40%) planned with about $4.21m^3$. 3)Assumed at height and 162cm did a lower part height with 860mm and the upper depth 340mm, did with 700mm where raises. the storage the ceiling which raises will select and considered and with 2200mm did. 4)Arrangement of the kitchen the kitchen form which is an open type (L/DK or L.D.K) arranged many in forms of letter.

• Structural Engineering and Mechanics
• /
• 제77권3호
• /
• pp.369-381
• /
• 2021

The seismic responses of elevated tanks considering liquid-structure interaction are presented under horizontal earthquake. The scaled model tank is fabricated to study the dynamic responses of anchored tank and newly designed uplift tank with replaced dampers. The natural frequencies for structural mode are obtained by modal analysis. The dynamic responses of tanks are completed by finite element method, which are compared with the results from experiment. The displacement parallel and perpendicular to the excitation direction are both gained as well as structural acceleration. The strain of tank walls and the axial strain of columns are also obtained afterwards. The seismic responses of liquid storage tank can be calculated by the finite element model effectively and the results match well with the one measured by experiment. The aim is to provide a new type of tank system with vertical constraint relaxed which leads to lower stress level. With the liquid volume increasing, the structural fundamental frequency has a great reduction and the one of uplift tank are even smaller. Compared with anchored tank, the displacement of uplift tank is magnified, the strain for tank walls and columns parallel to excitation direction reduces obviously, while the one perpendicular to earthquake direction increases a lot, but the values are still small. The stress level of new tank seems to be more even due to uplift effect. The new type of tank can realize recoverable function by replacing dampers after earthquake.

• 한국지진공학회논문집
• /
• 제27권1호
• /
• pp.1-12
• /
• 2023

Structures of high-rise buildings are less prone to earthquake damage. This is because the response acceleration of high-rise buildings appears to be small by generally occurring short-period ground motions. However, due to the increased construction volume of high-rise buildings and concerns about large earthquakes, long-period ground motions have begun to be recognized as a risk factor for high-rise buildings. Ground motion observed on each floor of the building is affected by the eigenmode of the building because the ground motion input to the building is amplified in the frequency range corresponding to the building's natural frequency. In addition, long-period components of ground motion are more easily transmitted to the floor or attached components of the building than short-period components. As such, high-rise buildings and non-structural components pose concerns about long-period ground motion. However, the criteria (ASCE 7-22) underestimate the acceleration response of buildings and non-structural components caused by long-period ground motion. Therefore, the characteristics of buildings' acceleration response amplification ratio and non-structural components were reviewed in this study through shake table tests considering long-period ground motions.

• 한국콘텐츠학회논문지
• /
• 제9권11호
• /
• pp.280-288
• /
• 2009

본 연구는 3차원 볼륨렌더링 영상의 체적변화를 위한 정밀한 모형을 고안, 제작하고 방사선치료계획 시스템의 재구성 과정에서 모형의 길이, 면적, 부피에 대한 변화를 평가하고자 하였다. 모형을 이용한 표준화된 전산화치료조준계획을 절편두께 1.25, 2.5, 5, 10mm로 시행한 후 3차원 재구성 영상을 절편두께와 모형의 형태에 따라 스캔방향(X), 두께(Y), 테이블 이동거리(Z), 면적(A), 부피(V)에 대한 변화와 분석자간 측정편차 및 최소값과 최대값을 측정하였다. 모형의 횡단면을 재구성한 3차원 볼륨렌더링 영상에서 절편두께가 1.25mm와 2.5mm에서 모형의 형태에 따라 X, Y, Z축 방향으로 최대 0.13cm(p<0.05)의 감소를 보였고 길이, 면적, 부피에 대하여 0.1cm, $0.8cm^2$, $3.99cm^3$(p<0.05) 정도의 감소를 보여 모형과 매우 근접한 영상을 획득하였다. 그러나 절편두께 5mm, 10mm에서 절편두께와 스캔 단면적이 증가하고 원형의 모형일수록 X, Y, Z축 방향으로 최대 0.58cm(p<0.05)의 감소를 보였고 길이, 면적, 부피에 대하여 최대 0.45cm, $8.21cm^2$, $11.03cm^3$(p<0.05)의 감소를 보였다. 모형을 이용한 방사선치료계획의 3차원 볼륨렌더링 영상의 절편두께와 모형의 형태에 따라 체적의 변화가 다양하게 발생하였으며 전산화치료조준계획을 시행할 경우 절편두께가 3mm 이하일 때 임상적으로 적절한 3차원 볼륨렌더링 영상을 얻을 수 있을 것으로 사료된다.

• 한국생산제조학회지
• /
• 제6권4호
• /
• pp.72-79
• /
• 1997

A study is a experiment which is figure out to optimum discharge cutting condition of the surface roughness, electronic discharging speed and electrode wear ration with Ton , Toff and V(voltage) as an input condition according to the current(Ip) in an electric spark machine : 1) Electrode is utilized Cu and Graphite. 2) Work piece is used the material of carbon steel. The condition of experiment is : 1) Current is varied 0.7(A) to 50(A) and the time of electric discharging to work piece in each time is 30(min) to 60(min). 2) After the upper side of work piece was measured in radius(5$\mu$m) of stylus analyzed the surface roughness to ade the table and graph of Rmax by yielding data. 3) Electro wear ratio is : \circled1Cooper was measured ex-machining and post-machining by the electronic balance. \circled2The ex-machining of graphite measured by it, the post-machining was found the data from volume $\times$specific gravity and analyzed to made its table and graph on ground the data. 4) In order to keep the accuracy of voltage affected to the work piece was equipped with the A.V. R and the memory scope was sticked to the electric spark machine. 5) In order to preserve the precision of current, to get rid of the noise occured by internal resistance of electric spark machine and to force injecting for the discharge fluid , it made the fixed table for a work piece to minimize the work error by means of one's failure during the electric discharging.

• 한국생산제조학회지
• /
• 제6권4호
• /
• pp.130-137
• /
• 1997

The demand for wire-cut EDM is increasing rapidly in the die and tool making industry. In this study machining characteristics such as machining rate, surface roughness, hand drum form and hardness of machined material are investigated experimentally under the conditions varing pulse on time, pulse off time, peak voltage, wire tension after fixing other conditions in SKD 11 and brass and brass workpiece. It was found that various operating conditions had significant influences on machining characteristics. But the hardness of workpiece was uneffected by operating conditions. Also it was obtained experimentally that brass workpeice had better machinability than SKD 11 one.dition according to the current(Ip) in an electric spark machine : 1) Electrode is utilized Cu and Graphite. 2) Work piece is used the material of carbon steel. The condition of experiment is : 1) Current is varied 0.7(A) to 50(A) and the time of electric discharging to work piece in each time is 30(min) to 60(min). 2) After the upper side of work piece was measured in radius(5$\mu$m) of stylus analyzed the surface roughness to ade the table and graph of Rmax by yielding data. 3) Electro wear ratio is : \circled1Cooper was measured ex-machining and post-machining by the electronic balance. \circled2The ex-machining of graphite measured by it, the post-machining was found the data from volume $\times$specific gravity and analyzed to made its table and graph on ground the data. 4) In order to keep the accuracy of voltage affected to the work piece was equipped with the A.V. R and the memory scope was sticked to the electric spark machine. 5) In order to preserve the precision of current, to get rid of the noise occured by internal resistance of electric spark machine and to force injecting for the discharge fluid , it made the fixed table for a work piece to minimize the work error by means of one's failure during the electric discharging.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2007년도 추계종합학술대회
• /
• pp.246-249
• /
• 2007

상변화 물질을 취급하는 수치해석에서는 온도, 압력, 체적, 엔탈피, 엔트로피 등의 열역학적 성질들의 수치값이 필요하다. 그러나 열역학적 성질들은 증기표나 선도 등의 형태로 주어지기 때문에 그대로 이용할 수는 없고 모델링하여 사용하여야 한다. 본 연구에서는 2차 스플라인 보간법과 비교함으로써, 과열증기의 모델링에 신경회로망의 적용 가능성을 검토하였다. 신경회로망은 온도와 압력, 2개의 입력에 대하여 비체적, 엔탈피 및 엔트로피, 3개의 출력을 얻을 수 있도록 입력층, 은닉층 및 출력층으로 구성되었다. 스플라인 보간법은 2차 다항식을 사용하였으며, 주어진 압력에 대한 소구간의 온도에 적용하였다. 신경회로망 모델링은 많은 출력 범위에서 2차 스플라인 보간법보다 우수한 백분율 오차를 보였으며, 이 결과로부터 과열증기 모델링에 신경회로망이 아주 강력한 방법임을 확인하였다.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 1996년도 춘계학술대회 논문집
• /
• pp.132-136
• /
• 1996

A Study is a experiment which is figure out to aptimum discharge cutting condition of the surfaceroughness, electric discharging speed and electro wear ratio with Ton Toff and V(voltage) as an input condition according to the current(Ip) in an electric spark machine ; 1)Electrode is utilized Cu(coper) and Graphite. 2)Work piece is used the material of carbon steel. The condition of experiment is; 1)Current is varied 0.7(A) to 50(A). 2)Pulse time(Ton) is varied 3($\mu$s) to 240($\mu$s) and also Toff is varied 7($\mu$s) to 20($\mu$s). 3)The time of electric discharging to work piece in each time is 30(min) to 60(min) 4)After the upper side of work piece was measured in radius (5${\mu}{\textrm}{m}$) of syulus analyzed the surface roughness to made the table and graph of Rmax by yielding data. 5)Electro wear ratio is; \circled1Coper was measured cx-machining and post machining but the electronic baiance. \circled2The ex-machining of graphite measured by it, the post-machining was found the data from volume specific gravity and analyzed to made its table and graph on ground the data 6)In order to keep the accuracy of voltage affected to the work piece was equipped with the A.V.R(Automatic Voltage Regulator). 7)The memory scope was sticked to the electric spark machine. 8)In order to preserve the precision of current, to get rid of the noise occured by internal resistance of electric spark machine and to force injecting for the discharge fluid, it made the fixed table for a work piece to minimize the work error by means of one's failure during the electric discharging According to above results, the surface roughness by the variation of electrodw and current was analyzed to compare KS(Korea Standards) It was decided the optimum condition of electric discharge cutting through analyzing the effect of electric discharge speed and electro wear ratio.