• Spatial Information Research
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• v.18 no.4
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• pp.75-88
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• 2010

Recent development in wireless communication and mobile positioning technologies make geosensor networks widely used in the various fields of real world. As a result, much research has been done on the middleware that uses limited energy resources efficiently. However, because traditional middleware does not consider the characteristics of sensor node, such as computing power and specification, the existing middleware call not support the sensor nodes with only the restricted system resource. Therefore, in this paper, we design and implement a new Bytecode based Data Service Middleware supporting energy efficiency in geosensor networks. At first, the proposed middleware provides the optimized functions for sensor nodes by using minimum by tee ode instruction set and data manager supporting hardware abstraction. Secondly, the proposed middleware increases the energy efficiency of sensor node through both data aggregation query processing and data filtering that minimize data transmission by eliminating unnecessary data. Finally, we show from our performance analysis that the proposed middleware is more energy efficient than the existing SwissQM.

• Journal of Environmental Science International
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• v.25 no.2
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• pp.323-329
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• 2016

In this study, the applicability of MBR process was evaluated to improve processing of personal sewage treatment facilities of $50m^3/day$ or less. As result of the research, stable discharge water quality could be secured as result of the MBR effector operation according to rate of inflow and inflow load and treatment efficiency of 98% or higher was shown by the membrane filtering method operation for SS, $BOD_5$. it was found that high treatment efficiency of 99% or higher. It is judged that detention time can be designed until 6.9 hr when applying MBR process on personal sewage treatment facilities with high pollution load and that cutback of pollution load can be possible through this study. It was shown that MBR process application reduces an annual cost of 4,829,600 won based on the basic unit calculation results and solves burden of amount of borne by causers according to excess of discharge water quality standards.

• Journal of Korea Multimedia Society
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• v.8 no.3
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• pp.355-361
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• 2005

This paper proposed a system collecting image information by agents in multi-threaded environment and then retrieving them with content based image retrieval. This system uses multi threads to retrieve web information effectively, then improves efficiency of CPU cycles to reduce latency time, which is the time requesting queries, executing communication processing 4hat the retrieval agents perform and filtering the retrieval results. Also, the agents for image retrieval use Java language, which is platform independent, to be suitable for distributed environment. Using JDBC to save the retrieved images, the agents are connected to database. The images themselves are stored in distributed agents' databases, and only the image indexes are stored in an index server so that the efficiency of storage and retrieval time can be improved.

• KSBB Journal
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• v.18 no.2
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• pp.140-144
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• 2003

The artificial sewage was treated using a vertical flow zeolite-filled reed bed. The artificial sewage was fec into the reed bed for 10 minutes every 6 hours at the hydraulic load 314 L/$m^2$ \ulcorner day. The filtering height of the reed bed was 100 cm and the zeolite mixture was filled in the reed bed. The mixture consisted of the same volume of two types of zeolites ; 0.5~1 mm and 1~3 mm in diameter. Annual average removal efficiency was CO$D_{Cr}$ 95.1%, T-N 49.5%, $NH{_4^+}$-N 99.4% and T-9 56.4%. T-N removal efficiency decreaced remarkably from 73 to 27% with the operating time. Most of T-P was adsorbed in the uper area of the reed bed. The major portion of adsorbed phosphorus was composed of Fe-, Ca- and reductant selubele Fe-P.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.9
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• pp.994-1000
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• 2004

We studied the characteristics of annular phase gratings as spatial frequency filters. We first calculated the Fraunhofer diffraction patterns of annular gratings and then got the modulation transfer function (MTF) from the zeroth order Hankel transform of the intensity distribution function. Binaryphase annular grating shows higher diffraction efficiency than binary phase rectangular grating. But the MTF decreases linearly in the low-frequency region as that of rectangular grating does. The diffraction pattern of 4-phase annular grating is similar to that of 2-phase grating and hence MTFs of the two are much alike. For 8-phase annular grating, the 7th order diffracted beam is the lowest one next to the first. Consequently, the diffraction efficiency is very high and the MTF graph is curved upward. The diffracted beams except the first order are negligible and hence the MTF characteristics are more improved in the case of 16-phase grating. But the degree of improvement becomes lowered c(Impaled with 8-phase grating. We made a 16-phase annular grating and measured its MTF. The experimental result agrees well with the calculated one.

• KSBB Journal
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• v.18 no.6
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• pp.506-510
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• 2003

The artificial sewage was treated using a horizontal flow zeolite-filled reed bed. The artificial sewage was fed into the reed bed for 10 minutes every 6 hours at the hydraulic load of 314 L/㎡$.$day. The filtering height of the reed bed was 100 cm and the zeolite mixture was filled in the reed bed. The mixttjre consisted of the same volume of two types of zeolite: 0.5∼l mm and 1∼3 mm in diameter. Annual average removal efficiency was CODcr 95.8%, T-N 56.5％, NH$\_$4/$\^$＋/-N 99.4％ and T-P 61.3%. T-N removal efficiency decreased remarkably from 84 to 32％ with the operating time.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.4
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• pp.186-191
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• 2012

DC Bus Electrolytic capacitors have been widely used in power conversion system because they can achieve high capacitance and voltage ratings with volumetric efficiency and low cost. This type of capacitors have been traditionally used for filtering, voltage smoothing, by-pass and other many applications in power conversion circuits requiring a cost effective and volumetric efficiency components. Unfortunately, electrolytic capacitors are some of the weakest components in power electronic converter. Many papers have proposed different methods or algorithms to determinate the ESR and/or capacitance C for fault diagnosis of the electrolytic capacitor. However, both ESR and C vary with frequency and temperature. Accurate knowledge of both values at the capacitors operating conditions is essential to achieve the best reference data of fault judgement. According to parameter analysis, the capacitance increases with temperature and the ESR decreases. Higher frequencies make the ESR and C to decrease. Analysis results show that the proposed electrolytic capacitor parameter estimation technique can be applied to reference signal of capacitor diagnosis systems successfully.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.9
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• pp.707-713
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• 2001

As the integrated circuit device shrinks to smaller dimensions, chemical mechanical polishing (CMP) process was requirdfo the global planarization of inter-metal dielectric (IMD) layer with free-defect. However, as the IMD layer gest thinner, micro-scratches are becoming as major defects. However, as the IMD layer gets thinner, micro-scratches are becoming as major defects. Micro-scratches are generated by agglomerated slurry, solidified and attached slurry in pipe line of slurry supply system. To prevent agglomerated slurry particle from inflow, we installed 0.5${\mu}{\textrm}{m}$ point of use (POU) filter, which is depth-type filter and has 80% filtering efficiency for the 1.0${\mu}{\textrm}{m}$ size particle. In this paper, we studied the relationship between defect generation and polished wafer counts to understand the exact efficiency fo the slurry filteration, and to find out the appropriate pad usage. Our experimental results showed that it sis impossible to prevent defect-causing particles perfectly through the depth-type filter. Thus, we suggest that it is necessary to optimize the slurry flow rate, and to install the high spray bar of de-ionized water (DIW) with high pressure, to overcome the weak-point of depth type filter.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.2C
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• pp.41-48
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• 2005

In this paper, we present a low complexity modified Gaussian model based pre-processing filter to improve the performance of H.264 compressed video. Video sequence captured by general imaging system represents the degraded version due to the additive noise which decreases coding efficiency and results in unpleasant coding artifacts due to higher frequency components. By incorporating local statistics and quantization parameter into filtering process, the spurious noise is significantly attenuated and coding efficiency is improved for given quantization step size. In addition, in order to reduce the complexity of the pre-processing filter, the simplified local statistics and quantization parameter are introduced. The simulation results show the capability of the proposed algorithm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.1153-1156
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• 2005

PACS system developments for improve of diagnosis efficiency for hospital duty efficiency and patients through various medical image diagnosis device. PACS system studies for nonfilm hospital, but still, image filtering technology Present high accuracy take a photograph image be not enough. On study image processing part is very importance. The fittest of image processing in order to using simple and essential filter try to improvrnent. The future, diagnosis of patients decide accuracy, low cost based Digital XRay system will be using.