• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 1991년도 추계학술대회 논문집
• /
• pp.44-47
• /
• 1991

Electron injection and memory retention chracteristics of the MNOS devices with thin oxide layer of 23${\AA}$ thick and silicon nitride layer of 1000${\AA}$ thick which are fabricated for this experiment. As a result, pulse amplitude increase oxide current is dominated in linearly increasing region of $\Delta$V$\_$FB/the decreasing region after saturation was due to the increased silicon nirtide current. In low pulse ampiltude $\Delta$V$\_$FB/ is not variated on temperature, but as temperature and pulse amplitude increase. $\Delta$V$\_$FB/ is decreased after saturation. And the decay rate during 10$^4$sec after electron injection was ohiefly dominated by the back tunneling of emission from memory trap to silicon. Memory retention characteristics in V$\_$FB/ stage was better than that of OV retention regardless of injection conditions.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 1991년도 추계학술대회 논문집
• /
• pp.40-43
• /
• 1991

The low-voltage ZnO varistor fabricated by a new method with three-composition seed grain are studied. The knee voltage about 5V$\_$0.5[A/$\textrm{cm}^2$]/ for sample #7 among the various samples are observed, and activation energy in the obmic region and trap level in the double sohottky region for each samples are 0.359∼0.450eV and 0.553∼0.620eV, respectively. It is concluded that the change of knee voltage may be caused by trap level in double sohottky region rather than activation energy in the ohmic region.

• 한국시뮬레이션학회논문지
• /
• 제4권2호
• /
• pp.31-40
• /
• 1995

A hybrid simulation model consists of real physical entities as well as simulated ones. It also contains logical processes for decision making for each operation units, a group of the entities. During the execution of such simulations, the physical and the logical processes consume real clock time while the activity durations of the simulated ones are generated. Due to the inherent chracteristics of the subjects of the communication channels. Since one can not undo an real event already taken place, the traditional central clock approach is used for the synchronization of the events(Kim[6]). However, there are still chances of causality errors due to the randomness in the communication delays. This error is not found in the distributed pure simulations. This paper explains the error in details and proposes a prevention scheme that is simple to implement.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 1998년도 하계종합학술대회논문집
• /
• pp.425-428
• /
• 1998

In this work, single-poly EEPROM has been designed and fabricated by using standard 0.8.mu.m CMOS process. The initial threshold voltage was aobut 0.8V but it increased ot about 6.5V after programming at Vds=11.5V and Vcg=6.5V. After erasing devices at Vs=14.2V, the threshold voltage decreased to about 1.5V. The programming time and erasing trime wree about 6ms. and 100ms. respectively. The erasing time can be reduced by applying a series of shorter erase pulse s instead of a long single erase pulse.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
• /
• pp.399-402
• /
• 2005

In ultra-high strength SFRCC(Steel Fiber Reinforced Cementious Composites), much silica fume are used to improve strength, flowability and durability. Silica fume have merits of filling the voids, enhancement of reheological chracteristics, production of secondary hydrates by pozzolanic reaction in reactive powder concretes. However silica fume has been imported in high-cost in domestic industry, we need to investigate replaceable material in stead of silica fume in a view of economy Therefore, in this paper, in order to investigate replacement of silica fume in ultra-high strength SFRCC we used the granulate blast-furnce slag with finess 4000, 6000, 8000. As a results, we have evaluated that the bigger the finess the more increase compressive strength of ultra-high strength SFRCC using the blast-furnce slag and there was no problem from the viewpoint of flowability and compressive strength when we use blast-furnce $50\%$ with replacement ratio of silica fume

• 전자공학회논문지D
• /
• 제34D권5호
• /
• pp.61-66
• /
• 1997

In this paper we report the fabrication of an InGaAs metal-semiconductor-metal (MSM) photodiode(PD) which an InAlAs barrier enhancement layer that has very low dark current and high speed chracteristics. The detector using Cr/Au schottky metal fingers with 4um spacing on a large active area of 300*300um$^{2}$ offers a low dark current of 38nA at 10V, a low capacitance of 0.8pF, and a high 3-dB bandwidth of 2.4 GHz. To our knowledge, these characteristics are better than any previously published results obtained from large area InGaAs MSM PD's. The RC equivalent model and frequency domain current response model considering transit time were also used to analyze the frequency characteristic of the fabricated device.

• 한국결정성장학회지
• /
• 제13권3호
• /
• pp.117-121
• /
• 2003

염화 니켈과 마그네슘 스테아린산 혼합 분말로부터 수소환원 공정에 의하여 니켈 분말을 제조하고 반응온도 및 마그네슘스테아린산의 첨가에 따른 분말의 특성을 검토하였다. 마그네슘 스테아린산을 함유한 경우 과도한 입자 성장의 억제로 인하여 입경 감소 효과가 있었다. 마그네슘 스테아린산의 함유량이 증가함에 따라 이에 따른 액상량의 증가로 인하여 입경 감소와 입자들간의 응집 정도에도 영향을 주었다.

• 한국주거학회:학술대회논문집
• /
• 한국주거학회 2008년 추계학술발표대회 논문집
• /
• pp.431-436
• /
• 2008

The aim of the research is to find out facility types and chracteristics of the community center in Seoul. To do so, we picked up 40 examples of a densely populated and low resident district in Seoul and then analyzed to find out the typical types and characteristics. The result of this study can be summarized as follows : By classifying community center complexs largely into a complex type with similar facilities and a complex type with different facilities, 8 types were derived. Depending on 4 characteristics, such as spatial composition, entrance type, circulation form, and complex facility type, 12 types of community center complexes were derived, and the characteristics of each type are presented.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1989년도 하계종합학술대회 논문집
• /
• pp.642-646
• /
• 1989

We have developed analysis program of discharge chracteristics of KrF laser system with charge transfer type, that studied about deposited energy, nonlinear discharge, and electron number density in the laser tube. With this program, voltagr, current, and deposited energy was calculated 27 KV,32.6 KA,200 MW at total pressure 2 atm and charging voltage 33 KV, respectively. At this condition, circuit parameters are L1=150nH, R1=$0.3{\Omega}$, L2=15nH, R2= $0.3{\Omega}$. In addition, nonlinear discharge resistance and electron number density was calculated ${\infty}{\sim}0.17{\Omega}.1{\times}10^{16}cm^{-3}$, respectively.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
• /
• pp.63-66
• /
• 1988

In the control of the robotic manipulators, the variable structure control method for the get Point Regualation has a advantage of the insensitivity about parameter variations and disturbances. When the robotic manipulators are controlled by a point-to-point scheme, no path constraint is considered. Thus, the variable structure control method will be effectively applied only if the trajectory of the robot hand is estimated precisely. In this paper, the joint trajectories in the joint space and the hand trajectory in the cartesian space are calculated by the variable structure control method, and an algorithm is suggested to elaborate the deviation error of the robot hand from a straight line path. The result of this study will become a base of the effective path planning about robotic manipulators with the variable structure control concept.