• Korean Journal of Environment and Ecology
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• v.36 no.5
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• pp.468-480
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• 2022

Although the construction of the Nakdong River Estuary Barrage (NEB) improved the water supply in the region, it cut off the longitudinal connectivity of the estuary aquatic ecosystem. Thus, the social demands for opening the NEB have been continuously raised, and the efforts to restore the aquatic ecosystem of the Nakdong River estuary began in 2017. Many fish species have inhabited the Nakdong River estuary. Since their habitat and migration characteristics vary widely, the sluice gate operation considering them is essential for the restoration of the aquatic ecosystem. Therefore, in this study, we monitored the fish species living and migrating in the Nakdong River estuary and analyzed the possibility of smooth movement of for each fish species by calculating the average flow velocity according to the type and the height of the gate opening. Moreover, we selected the target fish species for each month and suggested the sluice gate operation according to the depth of the main habitat to present the measures that are ideal for optimal restoration of the aquatic ecosystem in the Nakdong River estuary area.

• Journal of architectural history
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• v.27 no.2
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• pp.79-88
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• 2018

Foreign Reception Hall in Gyeongungung Palace was constructed during 1899-1902 according to Yesigjangjeong (禮式章程), Korean Empire's modern diplomatic protocol. This bulilding is a case worthy of notice, because its construction process was written in Jubon(奏本), Korean Empire's official document. Yesigjangjeong(禮式章程) regulates the process of diplomat's audience with Emperor Gojong. The process suggested that Foreign Reception Hall was designed as the place of the end as well as the beginning for audience. According to the process, diplomat came through main gate, Daehanmun and outer gate of main hall(Junghwajeon Hall, Audience Hall), then arrived at the stair to Foreign Reception Hall. After waiting time in the hall, he was going to be granted an audience with Emperor. And he exited through Foreign Reception Hall as the reverse way. This hall was constructed as western-style. Subcontracted carpenters and wood sculptors and laborers from China represents that chinese workers were prevailed in the government construction at that time. And modern building materials, such as glass, colored brick, sanitary wares and lightings were applied, which showed the new landscape in the middle of Gyeongungung Palace. Above all, official documents related with this hall reveals Korean Empire supervised this construction for diplomatic protocol. That is the identity of western-style buildings in Gyeongungung Palace.

• Journal of the Korean Institute of Landscape Architecture
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• v.22 no.4
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• pp.119-132
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• 1995

This study shows the characteristics of the early phenomena of the city plan Hanyang (old city Seoul). It consists of two steps. One is to search for the constructing principles of the geometric setting. And the other is to inquire and interpret the objects of beginning and ending points of that setting. The results based on geographic analysis and historical facts are as follows: 1) The city plan Hanyang shows a certain hierarchy:the major axis and the locations of the palace and the city set up in the prority. This priority made onto lower hierarchical plans such as the site plans of palaces and city wall. For example of the significant objects are Namdaemum (South Gate of the city wall) and Kwanghwamun (South Gate of the Palace). They are on the main axis, and became the basic points of the detailed city plans. 2) The palace palace on its major axis, right-angled minor axis, and 4 grade inclination to north. The four small city wall gates located on the base of four greater gates. 3) The geometric characteristics as constructing principle found on certain hierarchical order. Thus, the natural elements as mountains, had an important effect on the arrangement of major facilities and those main constructions made on lower - hierarchical settings. 4) These facts related closely to the philosophy of Jung, Do-Jon, the initiative planer of the Hanyang.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.682-687
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• 2014

We have performed reverse gate bias stress tests on AlGaN/GaN-on-Si Heterostructure FETs (HFETs). The shift of threshold voltage ($V_{th}$) and the reduction of on-current were observed from the stressed devices. These changes of the device parameters were not permanent. We investigated the temporary behavior of the stressed devices by analyzing the temperature dependence of the instabilities and TCAD simulation. As the baseline temperature of the electrical stress tests increased, the changes of the $V_{th}$ and the on-current were decreased. The on-current reduction was caused by the positive shift of the $V_{th}$ and the increased resistance of the gate-to-source and the gate-to-drain access region. Our experimental results suggest that electron-trapping effect into the shallow traps in devices is the main cause of observed instabilities.

• Transactions on Electrical and Electronic Materials
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• v.17 no.6
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• pp.329-334
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• 2016

In this work, the temperature dependence of electrical parameters of nanoscale SOI (silicon-on-insulator) TG (triple gate) n-FinFET (n-channel Fin field effect transistor) was investigated. Numerical device simulator $ATLAS^{TM}$ was used to construct, examine, and simulate the structure in three dimensions with different models. The drain current, transconductance, threshold voltage, subthreshold swing, leakage current, drain induced barrier lowering, and on/off current ratio were studied in various biasing configurations. The temperature dependence of the main electrical parameters of a SOI TG n-FinFET was analyzed and discussed. Increased temperature led to degraded performance of some basic parameters such as subthreshold swing, transconductance, on-current, and leakage current. These results might be useful for further development of devises to strongly down-scale the manufacturing process.

• The Journal of Korean Medicine
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• v.17 no.2 s.32
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• pp.88-99
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• 1996

Impotence is defined as a consistent inability to achieve or maintain penile erection that is adequate for completion of sexual intercourse. In oriental midicine, the chief cause of impotence is the decline of the fire from the gate of life, and in western medicine that is psycogenic and organic. Because of the increase aging people and psycologic stress that modern people get, impotence became common. This bibliographic study on impotence in the oriental and western medicine books has come to the following conclusions. 1. The main cause of impotence in the oriental medicine is the decline of the fire from the gate of life(命門火衰), followed by the deficiency of both heart and spleen(心脾兩虛), the depression of Liver energy(肝氣鬱結), and attack of blended wetness and heat to the lower wanner(濕熱下注). 2. The theraphics of impotence in oriental medicine are warming and strenghthening Kidney. softness of Liver energy, tonifying the Kidney to relieve mental strain, clear away the wetness-heat, and infairment of Heart and Spleen. 3. The prescriptions of impotence are Yugyeyum, Gyibitang, Soyosan, Sunjitang, and Yongdamsagantang. 4. In the western medicine, psycotherapy, medical therapy and surgical therapy are the major way to treat impotence.

• Transactions of Materials Processing
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• v.20 no.5
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• pp.333-338
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• 2011

Rapidly developing IT technologies in recent years have raised the demands for high-precision optical lenses used for sensors, digital cameras, cell phones and optical storage media. Many techniques are required to manufacturing high-precision optical lenses, including multi-beam sensing lenses investigated in the current study. In the case of injection molding for thick lenses, a shrinkage phenomenon often occurs during the process. This shrinkage is known to be the main reason for the lower optical quality of the lenses. In the present work, a CAE analysis was conducted simultaneously with experiments to understand and minimize this phenomenon. In particular, the sectional area of a gate was varied in order to understand the effects of packing and cooling processes on the final shrinkage pattern. As a result of this study, it was demonstrated that a dramatic reduction of the shrinkage could be obtained by increasing the width of the gate.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.213-216
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• 2003

Recently a new high power device GCT (Gate Commutated Turn-off) thyristor has been successfully introduced to high power converting application areas. GCT thyristor has a quite different turn-off mechanism to the GTO thyristor. All main current during turn-off operation is commutated to the gate. Therefore, IGCT thyristor has many superior characteristics compared with GTO thyristor; especially, snubberless tum-off capacibility and higher turn-on capacibility. The basic structure of the GeT thyristor is same as that of the GTO thyristor. This makes the blocking voltage higher and controllable on-state current higher. The turn-off characteristic of the GCT thyristor is influenced by the minority carrier lifetime and the performance of the gate drive unit. In this paper, we present turn-off characteristics of the 2.5kV PT(Punch-Through) type GCT as a function of the minority carrier lifetime and variation of the doping profile shape of p-base region.

• Journal of Power Electronics
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• v.17 no.4
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• pp.1117-1126
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• 2017

The main contribution of this paper is the use of sensorless active diodes to generate the gate signals for a three-phase boost-rectifier with a self-powered control scheme. The sensorless operation is achieved making use of the gate control signals generated by the active diode schemes on each of the switching devices using a pulse width half-controlled boost rectifier modulation technique (PWM-HCBR). The proposed scheme synchronizes the gate control signals with a three phase voltage supply. Autonomous operation is obtained making use of the output DC bus to feed the control circuitry, the active diodes and the driver circuitry. The three-phase boost-rectifier is supplied by a three-phase permanent magnet electric generator powered by a solar concentrator dish with variable voltage and variable frequency conditions. Experimental results report an efficiency of up to 94.6% for 25 W and an input of 3.6 V peak per phase with 450.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1485-1488
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• 1997

The capacity of memory chip has increased vert quickly and 64MDRAM becomes main product in semiconductor manufacturing lines consists of many sequential processes, including etching process. although it needs direct sensing of wafer state for the accurae detching, it depends on indirect esnsing and sample test because of the complexity of the plasma etching. This equipment receives the inner light of etch chamber through the viewport and convets it to the voltage inetnsity. In this paper, EDP voltage signal has a new role to detect etching failure. First, we gathered data(EPD sigal, etching time and etchrate) and then analyzed the relationships between the signal variatin and the etch rate using two neural network modeling. These methods enable to predict whether ething state is good or not per wafer. For experiments, it is used High Density Inductive coupled Plasma(HDICP) ethcing equipment. Experiments and results proved to be abled to determine the etching state of wafer on-line and analyze the causes by modeling and EPD signal data.