• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.4
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• pp.85-94
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• 2003

The asynchronous design methods proved to have the higher performance in power consumption and execution speed than synchronous ones because it just needs to activate the required module without feeding clock in the system. Despite the advantage of CISC machine providing the variable addressing modes and instructions, its execution scheme is hardly suited for a synchronous Pipeline architecture and incurs a lot of overhead. This paper proposes a novel asynchronous pipeline architecture, A80sl, whose instruction set is fully compatible with that of Intel 80C51, an embedded micro controller. We classify the instructions into the group keeping the same execution scheme for the asynchronous pipeline and optimize it eliminating the bubble stage that comes from the overhead of the multi-cycle execution. The new methodologies for branch and various instruction lengths are suggested to minimize the number of states required for instructions execution and to increase its parallelism. The proposed A80C51 architecture is synthesized with 0.35${\mu}{\textrm}{m}$ CMOS standard cell library. The simulation results show higher speed than that of Intel 80C51 with 36 MHz and other asynchronous counterparts by 24 times.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.148-148
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• 2011

Recently, there have been many research activities to develop the large-area plasma source, which is able to generate the high-density plasma with relatively good uniformity, for the plasma processing in the thin-film solar cell and display panel industries. The large-area CCP sources have been applied to the PECVD process as well as the etching. Especially, the PECVD processes for the depositions of various films such as a-Si:H, ${\mu}c$-Si:H, Si3N4, and SiO2 take a significant portion of processes. In order to achieve higher deposition rate (DR), good uniformity in large-area reactor, and good film quality (low defect density, high film strength, etc.), the application of VHF (>40 MHz) CCP is indispensible. However, the electromagnetic wave effect in the VHF CCP becomes an issue to resolve for the achievement of good uniformity of plasma and film. Here, we propose a new electrode as part of a method to resolve the standing wave effect in the large-area VHF CCP. The electrode is split up a series of strip-type electrodes and the strip-type electrodes and the ground ones are arranged by turns. The standing wave effect in the longitudinal direction of the strip-type electrode is reduced by using the multi-feeding method of VHF power and the uniformity in the transverse direction of the electrodes is achieved by controlling the gas flow and the gap length between the powered electrodes and the substrate. Also, we provide the process results for the growths of the a-Si:H and the ${\mu}c$-Si:H films. The high DR (2.4 nm/s for a-Si:H film and 1.5 nm/s for the ${\mu}c$-Si:H film), the controllable crystallinity (~70%) for the ${\mu}c$-Si:H film, and the relatively good uniformity (1% for a-Si:H film and 7% for the ${\mu}c$-Si:H film) can be obtained at the high frequency of 40 MHz in the large-area discharge (280 mm${\times}$540 mm). Finally, we will discuss the issues in expanding the multi-electrode to the 8G class large-area plasma processing (2.2 m${\times}$2.4 m) and in improving the process efficiency.

• Applied Chemistry for Engineering
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• v.26 no.2
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• pp.205-209
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• 2015

CCU (Carbon Capture & Utilization) has a potential technology for the reduction and usage of carbon dioxide which is greenhouse gas emitting from a fossil fuel buring. To decompose the carbon dioxide, a three phase gliding arc plasma-catalytic reactor was designed and manufactured. Experiments of carbon dioxide reduction was performed by varying the gas flow rate with feeding the $CO_2$ only as well as the input power, the catalyst type and steam supply with respect to the injection of the mixture of $CO_2$ and $CH_4$. The $CO_2$ decomposition rate was 7.9% and the energy efficiency was $0.0013L/min{\cdot}W$ at a $CO_2$ flow rate of 12 L/min only. Carbon monoxide and oxygen was generated in accordance with the destruction of carbon dioxide. When the injection ratio of $CH_4/CO_2$ reached 1.29, the $CO_2$ destruction and $CH_4$ conversion rates were 37.8% and 56.6% respectively at a power supply of 0.76 kW. During the installation of $NiO/Al_2O_3$ catalyst bed, the $CO_2$ destruction and $CH_4$ conversion rates were 11.5% and 9.9% respectively. The steam supply parameter do not have any significant effects on the carbon dioxide decomposition.

• Journal of Biosystems Engineering
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• v.6 no.2
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• pp.33-47
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• 1982

To modernize the conventional rice post production technology and reduce grain losses, a transition toward the wet-paddy threshing system has been strongly demanded. The head-feeding type thresher with pneumatic separation has been used dominantly for threshing dried-paddy, but some adverse effects in separation performance for threshing wet-paddy is encounterred. In order to solve the problems, the development of thresher with an additional oscillating sieve to the conventional pneumatic separation has been recommanded. This study was intended to evaluate the separating performance of thresher with oscillating sieve which was attached additionally to the conventional auto-thresher equipped with separation system of blower and suction fan. For different feed rates and rice varieties, wet-and dry-material were tested with threshers attached with and without oscillating sieve. Results of the study are summarized as follows: 1. When the feed rates were 480 and 640 kg/hr, there was no statistically significant difference in power reqirements between the threshers with and without an additional sieve device for both dry-and wet-threshing. However, when the feed rate was 960 kg/hr, power requirements of thresher without sieve were greater for wet-paddy threshing than the thresher with the additional sieve separator by about 20% points. 2. With additional oscillating sieve device, the ratios of total weights of whole grains including grains with branch let and damaged grains to the total output did not show statistical difference among the feed rates. However, with pneumatic separation the ratio was decreased as the level of feed rate increased. 3. The total amount of grains with branchlet (including broken panicle) increased with the moisture content. For both the wet-and dry-material threshing with the additional oscillating sieve, the percent of grains with branchlet to the total output decreased greatly as the feed rate increased. 4. The output of the damaged grains increased as moisture content decreased. Especially, for the dry-paddy threshing, the additional sieve separating device produced more damaged grains than the pneumatic separation at all feed rates. 5. Generally, for dry paddy threshing, the separating performance of the thresher with the additional sieve device was better at all feed rates, showing greater difference with increasing feed rates. 6. Separating losses were greater with the pneumatic than sieve separation for both the wet-and dry-threshing. 7. The overall comparison of separating performance of threshers tested with and without an additional sieve device showed that the former was more effective than the latter for the dry-material threshing. However, for the wet-paddy threshing, the separation performance with a sieve device was better than the pneumatic only when the feed rate was high.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.1
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• pp.13-21
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• 1997

In this paper, the oscillator type active antenna used as an element of active phased array antenna is designed and fabricated using slot coupling. The radiating element and active circuit are fabricated on each layer respectively and coupled electromagnetically through slot on the ground plane. This structure can solve the problems such as narrow bandwidth of microstrip antenna, spurious radiation by active circuits, and spaces for integration of the feeding circuits which are caused by integrating antennas with oscillator circuits in the same layer. The active antenna in this paper, the oscillation frequency can be tuned linearly by controlling the drain bias voltage of FET. The frequency tuning range is between 12.37 GHz to 12.65 GHz when bias voltage is varied from 3V to 9V, thus frequency tuning bandwidth is 280 MHz (2.24%). The output power of antenna is uniform within 5dB over frequency tuning range. Therefore this active antenna can be used as an element of linear or planar active phased array antennas.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.4
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• pp.247-254
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• 2012

Vitrification technology has been widely applied as one of effective processing methods for wastes generated in nuclear power plants. The advantage of vitrifying for low- and intermediate-level radioactive wastes has a large volume reduction and good durability for the final products. Recently, a filter using on HVAC(Heating Ventilating & Air Conditioning System) is composed with media (glass fiber) and separator (aluminum film) has been studied the proper treatment technology for meeting the waste disposal requirement. Present paper is a feasibility study for the filter vitrification that developing of the glass compositions for filter melting and melting test for physicochemical characteristic evaluation. The aluminum metal of film type is preparing with 0.5 cm size for proper mixing with glass frit, glass fiber is also preparing with 1 cm size within crucible. The glass compositions should be developed considering molten glass are related with wastes reduction. Glass compositions obtained from developing on glass formulation are mainly composed of $SiO_2$ and $B_2O_3$ for aluminum metal. A variety of factors obtained from the glass formulation and melting test are reviewed, which is feeding rate and glass characteristics of final products such as durability for implementing the wastes disposal requirement.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.308-314
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• 2010

This study was conducted to investigate the characteristics and concentrations of ammonia produced from the livestock swine nightsoil treated with or without the livestock - environment improving agents. Odor generating device made of acryl was made by volume of 96 L to sample the ammonia odor. When swine night soil was placed in the device, concentration of ammonia averaged out at about 23.4 ppmv and ranged from 16 ppmv to 40 ppmv. Removal efficiencies of them showed 50% to 90% as compared to initial level before spraying, when the spray type agents were used immediately after they purchased. The persistence of the efficiency was retained for first two days. Among the agents, the natural deodorant showed the best efficiency of 87 to 99%. To evaluate the effects of 5 kinds of dietary probiotic powders, the experiments were conducted and based dietary treatments without antibiotics on growing piglets. In experiments, 60 piglets ($6.3{\pm}0.2\;kg$) were subjected to a 35-day feeding trial in which the effects of the dietary probiotic powder on the ammonia emission were compared. The ammonia gas emission was measured for every week. Ammonia emission from the swine nightsoil obtained from piglets supplemented with the probiotics power was lower than that of the nightsoil obtained from pigs in the control treatment (without probiotics). In ammonia removal efficiencies of the experimental groups, some products showed from 71% to 99% removal efficiencies throughout the entire period as compared to the control group. On the other hand, initial reduction of ammonia in some product was effective temporarily. After then, it did not show any reduction efficiency of ammonia.

• Journal of Biosystems Engineering
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• v.11 no.2
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• pp.31-40
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• 1986

Cylindrical and conical types of grain-straw separation equipment which has a stationary crimped sieve drum with rotating inner rotor were constructed. The developed equipments were tested to investigate the characteristics of separating performance under various mechanical conditions and crop conditions. As increase of the inclination of equipment and decrease of pitch of cover vane, the grain recovery was increased while straw rejection was decreased. The grain recovery and overall efficiency were decreased as the rotor speed and feeding velocity were increased for both varieties of rice, moisture contents, and test equipments. Conical prototype equipment performed higher straw rejection, lower grain recovery, and lower power requirement. However, separation performance of conical type equipment was more widely varied with various test conditions compared to cylindrical one. The performance of both equipments showed relatively insensitive to crop feedrate and crop properties, such as variety, moisture content, and grain-to-straw ratio.