• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.511-519
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• 1992

A microcomputer based control system was constructed to save energy consumption in the thermal sterilizing process. The functional accuracy of system was evaluated through the analysis of the thermal diffusivities of the model solid food, Alaska pollack surimi. The heat penetration curves obtained through the experiments were typical for solid foods. The practical thermal diffusivity calculated from heat penetration curve was a constant value at steady sterilizing temperature, and this was independent of the holding time. At different temperatures, the thermal diffusivity values did not show remarkable differences when compared with those predicted by some experimental equations cited from the literatures. The maximal difference was within the range of $\pm10.0\%$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.520-528
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• 1992

In order to establish the standard conditions for thermal sterilization of foods, a microcomputer based $F_o-value$ measuring system was developed upon the basis of the time-temperature profile in food. $F_o-value$ was calculated simultaneously from the time-temperature profile, and described as integrated lethality during the whole sterilization process. The accuracy of system was evaluated by the analysis of thermal diffusivity of the model solid food, Alaska pollack surimi. The $F_o-value$ could be measured precisely under the different sterilizing conditions as the varied time and temperature. The practical thermal diffusivities from various sterilizing conditions agreed well to the values predicted by some experimental equations suggested in the literatures. The differences were within the range of $\pm12\%$.

• KSBB Journal
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• v.5 no.3
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• pp.269-277
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• 1990

Methylobacillus sp. SK1, an obligate methylotroph, was cultivated in a fed-batch culture using DO as a methanol feeding indicator with a micro computer-aided control system. While 2.07g/l of cell density was obtained after 13 hr in the batch culture (initial methanol concentration: 1.0%(v/v)),45.3g/l of cell density was obtained after 17 hr by feeding methanol and metal ions in the fed-batch culture with oxygen supply. The high-density biomass was obtained in short cultuivation time by fed-batch culture with feedback control, and consequently the biomass productivity was significantly increased. It was mainly due to extension of logarithmic growth period by methanol feeding without methanol inhibition and intensive aeration without DO limitation with microcomputer-aided control system.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.5
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• pp.442-451
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• 1997

We described a miniaturization of microstrip filters by the exact synthesis. With the exact synthesis, we can design completely new circuits physically realizable. The complex procedure for the network synthesis could be reduced by using computer software. It is a new design procedure ensuring the creation of optimum networks which have minimum number of elements. The exact synthesis gives more possibilities to make wideband filters which require bandwidth of 50~100 %. S-plane Bandpass prototypes are made with non-redundant filter synthesis technique that has transmission zero locations at required frequencies. Because this method uses the transmission lines which lengths are ${\lambda}$/4 at the stopband center frequency, we can reduce the size of the filter dramatically.

• Journal of the Korean Chemical Society
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• v.39 no.9
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• pp.685-691
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• 1995

EHMACC and EHPC programs written in VAX version to calculate the tight-binding extended Huckel method is converted into the micro-soft fortran available to PC. The band calculation of LaNiO3 unit cell and extended ($2{\times}2{\times}1$) cell with perovskite structure is made by the PC/386 and PC/486. The calculation is also made for the DOS and the COOP. It is supposed that the electronic property of $LaNiO_3$ is semiconductor along to the ${\Gamma}{\rightarrow}H,\;H{\rightarrow}N,\;and\;N{\rightarrow}{\Gamma}(2D)$ direction with band gap about 0u.35 eV, while metal property in ${\Gamma}{\rightarrow}P\;and\;P{\rightarrow}N(3D)$ direction. The oxygen atom property in $LaNiO_3$ is more effectively affected by oxygen atom position than defect of nickel atom.

• Journal of Biosystems Engineering
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• v.20 no.1
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• pp.73-86
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• 1995

The automatic control system in the greenhouse have to be developed to the direction of considering various factors the variables such as condition of the cultivation and greenhouse, the properties and types of products. Therefore, it is more important to set up variables appropriately than the problems of automatic control system itself, and the automatic control system which satisfy these problems should be simplified in the aspect of operation. In addition, even the individual automations are not perfect yet, so more studies are required for the development of comprehensive automatic system in korea. This study was carried out to automatize environment control systems for greenhouse, especially from most intensive labor requiring parts such as watering, irrigating liquefied fertilizer, spraying chemicals, mixing and ventilation system, etc. The results are summarized as follows. 1. Control type tensiometer was expected to be desirable in the automation of watering system, therefore, a new tensiometer was designed and developed through this study. 2. The chemical spraying system developed through this study was found to be excellent in the aspect of operation. 3. When pulse type water discharge meter was used in the mixing of liquefied fertilizer and chemical solution, the error of mixing were range $\pm$0.1~0.15%. 4. The water level switch of electrod type used for controlling water level was found to be affective in both control performance and operation cost. 5. The water and level control system can be omitted if each tank size are standardized in accordance with greenhouse size, therefore, the installation cost might be significantly reduced. 6. The developed general controller was excellent in hardware parts, but still remained to be improved in software parts.

• Journal of KIISE:Information Networking
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• v.30 no.3
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• pp.316-328
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• 2003

In this paper, we propose and analyze two adaptive channel allocation schemes for supporting multimedia traffics in hierarchical cellular systems. It is guaranteed to satisfy the required quality of service of multimedia traffics according to their characteristics such as a mobile velocity for voice calls and a delay tolerance for multimedia calls. In the scheme 1, only slow-speed voice calls are allowed to overflow from macrocell to microcell and only adaptive multimedia calls can overflow from microcell to macrocell after reducing its bandwidth to the minimum channel bandwidth. In the scheme II, in addition to the first scheme, non-adaptive multimedia calls can occupy the required channel bandwidth through reducing the channel bandwidth of adaptive multimedia calls. The proposed scheme I is analyzed using 2-dimensional Markov model. Through computer simulations, the analysis model and the proposed schemes are compared with the fixed system and two previous studies. In the simulation result, it is shown that the proposed schemes yield a significant improvement in terms of the forced termination probability of handoff calls and the efficiency of channel usage.

• Journal of Advanced Navigation Technology
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• v.23 no.4
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• pp.316-321
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• 2019

In this paper, by applying the constant current principle we develop an impedance measurement system which can measure the high precision impedance of various electric materials by using microprocessor. This measurement system board has an interface device for acquiring digital data from an external device including an impedance measuring device, and system software is also developed by a firmware program executed on such an embedded board. It can measure the high precision impedance of a specific band with 1/32768 precision by using 15-bit ADC(analog to digital converter) and calculate it to the five digits to the right of the decimal point(fraction part). Data is transmitted through a USB interface of a general computer and a measuring device to manage digital data. An impedance measurement system equipped with a communication function capable of a more general and easy-to-use interface than other equipment is developed and verified.

• Progress in Medical Physics
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• v.19 no.2
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• pp.102-112
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• 2008

We developed a high-resolution micro-CT system based on rotational gantry and flat-panel detector for live mouse imaging. This system is composed primarily of an x-ray source with micro-focal spot size, a CMOS (complementary metal oxide semiconductor) flat panel detector coupled with Csl (TI) (thallium-doped cesium iodide) scintillator, a linearly moving couch, a rotational gantry coupled with positioning encoder, and a parallel processing system for image data. This system was designed to be of the gantry-rotation type which has several advantages in obtaining CT images of live mice, namely, the relative ease of minimizing the motion artifact of the mice and the capability of administering respiratory anesthesia during scanning. We evaluated the spatial resolution, image contrast, and uniformity of the CT system using CT phantoms. As the results, the spatial resolution of the system was approximately the 11.3 cycles/mm at 10% of the MTF curve, and the radiation dose to the mice was 81.5 mGy. The minimal resolving contrast was found to be less than 46 CT numbers on low-contrast phantom imaging test. We found that the image non-uniformity was approximately 70 CT numbers at a voxel size of ${\sim}55{\times}55{\times}X100\;{\mu}^3$. We present the image test results of the skull and lung, and body of the live mice.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.7
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• pp.1218-1226
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• 2008

With the development of semiconductor integrated technology and with the increasing use of multimedia functions in computer, more functions have been implemented as hardware. Nowadays, most microprocessors beyond 32 bits generally implement an integer multiplier as hardware. However, as for a divider, only specific microprocessor implements traditional SRT algorithm as hardware due to complexity of implementation and slow speed. This paper suggested an algorithm that uses a multiplier, 'w bit $\times$ w bit = 2w bit', to process $\frac{N}{D}$ integer division. That is, the reciprocal number D is first calculated, and then multiply dividend N to process integer division. In this paper, when the divisor D is '$D=0.d{\times}2^L$, 0.5 < 0.d < 1.0', approximate value of ' $\frac{1}{D}$', '$1.g{\times}2^{-L}$', which satisfies ' $0.d{\times}1.g=1+e$, $e<2^{-w}$', is defined as over reciprocal number and then an algorithm for over reciprocal number is suggested. This algorithm multiplies over reciprocal number '$01.g{\times}2^{-L}$' by dividend N to process $\frac{N}{D}$ integer division. The algorithm suggested in this paper doesn't require additional revision, because it can calculate correct reciprocal number. In addition, this algorithm uses only multiplier, so additional hardware for division is not required to implement microprocessor. Also, it shows faster speed than the conventional SRT algorithm and performs operation by word unit, accordingly it is more suitable to make compiler than the existing division algorithm. In conclusion, results from this study could be used widely for implementation SOC(System on Chip) and etc. which has been restricted to microprocessor and size of the hardware.