• Proceedings of the KSPS conference
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• 2003.10a
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• pp.101-104
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• 2003

In this paper, speech quality is improved by removing abrupt noise intervals and then substituting the gaps with estimates of the previous speech waveform. An abrupt noise detection signal has been proposed as a prediction error signal by utilizing LP coefficients of the previous frame. Abrupt noise intervals are estimated by using spectral energy. After removing estimated noise intervals, we applied several waveform substitution techniques such as zero substitution, previous frame repetition, pattern matching, and pitch waveform replication. To prove the validity of our algorithm, the LPC spectral distortion test and the recognition test are executed and, the results show that the speech quality is fairly well improved.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.4
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• pp.94-102
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• 1996

This study was accomplished to get the basic data for the optimum chemical feed, evaluating interference between tastes and odors chemicals and coagulants in existing water treatment processes. During the tastes and odors occurs at D intaking tower area in 1995, PAC(Powdered Activated Carbon) feed with coagulants was PAC feed only and with coagulant simultaneously were appeared TON removal efficiency about 84%-87% within 20 min reaction time, but feed with time intervals was about 98% TON removal efficiency. Therefore in the case of PAC feed with coagulant, it is effective to feed coagulant on some time intervals in removing tastes and odors. It is not effective to feed PAC with chlorine dioxide($ClO_2$) or chlorine simultaneously in removing tastes and odors, because these chemicals were reduced the adsorption capacity of PAC.

• Journal of Korea Multimedia Society
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• v.22 no.10
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• pp.1199-1207
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• 2019

Video surveillance data, which is used for preemptive or post-emptive action against any event or accident, is required for monitoring the location, but is reducing the capacity of the image data by removing intervals for cost reduction and system persistence. Such a video surveillance system is fixed in a certain position and monitors the area only within a limited angle, or monitors only the fixed area without changing the angle. At this time, the video surveillance system that is monitored only within a limited angle shows that the variation object such as the floating population shows different status in the image, and the background of the image maintains a generally constant appearance. The static objects in the image do not need to be stored in all the images, unlike the dynamic objects that must be continuously shot, and occupy a storage space other than the necessary ones. In this paper, we propose a mechanism to analyze the image, store only the small size image for the fixed background, and store it as image data only for variable objects.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.2
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• pp.218-230
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• 2020

The single anatomical attribute that has the greatest influence on acoustic scattering from fish is the presence or absence of a swimbladder. This study examined the effect of removing the gas from the swimbladder on the broadband backscattering characteristics of six species of swimbladdered fish: striped beakperch Oplegnathus fasciatus, black scraper Thamnaconus modestus, dark-banded rockfish Sebastes inermis, goldeye rockfish Sebastes thompsoni, black rockfish Sebastes schlegeli and panther puffer Takifugu pardalis. Before and after removing the gas from the swimbladder, the species-specific, frequency-dependent backscattered echo signals from anaesthetized individuals of each fish species were measured at approximately 1° intervals spanning a 90° aspect angle range from -45° (head down) to +45° (head up) using a broadband echo sounder operating at 100-200 kHz. The relationship between the wavelength-normalized backscattering cross section (σ/λ²) and fish length (L/λ) was calculated for each species. The average σ/λ² value for the six fish species at a L/λ range of 19.79-25.85, with a mean of 22.89, was reduced by approximately 52.3% when the gas was removed.

• Journal of Korean Institute of Industrial Engineers
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• v.27 no.4
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• pp.394-405
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• 2001

Since most real-world application data involve continuous-valued attributes, properly addressing the discretization process for constructing a decision tree is an important problem. A continuous-valued attribute is typically discretized during decision tree generation by partitioning its range into two intervals recursively. In this paper, by removing the restriction to the binary discretization, we present a hybrid multi-interval discretization algorithm for discretizing the range of continuous-valued attribute into multiple intervals. On the basis of experiment using semiconductor etching machine, it has been verified that our discretization algorithm constructs a more efficient incremental decision tree compared to previously proposed discretization algorithms.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.10
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• pp.89-97
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• 1997

To extract time-varying evoked potential (EP), segement latency corrected average method is presented. This method is composed of three steps. First, adaptive filtering for reducing the effect of artifacts and removing background noise is performed. Next, validated intervals of individual segments are aligned, and latency components are detected by cross-correlation between the previously obtained and measured EPs within the intervals. Finally, after the detected latency component, responses of segments are groupe and averaged, the shole corrected EP signal is obtained. In the experiments, the resutls of the conventional methods including simple averaging, Woody's method, and peak component latency corrected averaging are obtained, the results compared with the present method for evaluating performance. Therefore, the presented method confirms that it reflects the latency variations of fundamental peaks and gets the improved EP.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.299-303
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• 2011

This paper proposes a novel sensorless maximum power point tracking (11PPT) algorithm for PV systems. The method is based on dividing the operating time into several intervals in which the PV terminals are short circuited in one interval and the calculated short-current of the PV is obtained and used to determine the optimum operating point where the maximum output power can be obtained. The proposed MPPT algorithm has been introduced into a current-controlled boost converter whose duty ratio is controlled to the maintain MPP condition. The same sequence is then repeated regularly capturing the PV maximum power. The main advantage of this method is eliminating the current sensor. Meanwhile, this MPPT algorithm reduces the power oscillations around the peak power point which occurs with perturbation and observation algorithms. In addition, the total cost will decrease by removing the current sensor from the PV side. Finally, simulation results confirm the accuracy of the proposed method.

• Journal of Pharmaceutical Investigation
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• v.30 no.4
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• pp.295-297
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• 2000

A new method to evaluate erosion of biodegradable polymer, polyanhydrides, was developed. The polymer devices were prepared with the melt-casting method and weight loss was accurately measured after agitating the devices in buffers (pH 1-9), and removing the device at selected time intervals and freeze-drying the device. The erosion rate was estimated from the plot of the weight loss(%) of device as a function of time. The freeze-drying technique used in this study is particularly useful for estimating the erosion rate of biodegradable polymer.

• Kyungpook Mathematical Journal
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• v.60 no.1
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• pp.1-20
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• 2020

A simple but elegant result of Rival states that every sublattice L of a finite distributive lattice 𝒫 can be constructed from 𝒫 by removing a particular family 𝒥_L of its irreducible intervals. Applying this in the case that 𝒫 is a product of a finite set 𝒞 of chains, we get a one-to-one correspondence L ↦ 𝒟_𝒫(L) between the sublattices of 𝒫 and the preorders spanned by a canonical sublattice 𝒞^⋄ of 𝒫. We then show that L is a tight sublattice of the product of chains 𝒫 if and only if 𝒟_𝒫(L) is asymmetric. This yields a one-to-one correspondence between the tight sublattices of 𝒫 and the posets spanned by its poset J(𝒫) of non-zero join-irreducible elements. With this we recover and extend, among other classical results, the correspondence derived from results of Birkhoff and Dilworth, between the tight embeddings of a finite distributive lattice L into products of chains, and the chain decompositions of its poset J(L) of non-zero join-irreducible elements.

• Journal of Advanced Information Technology and Convergence
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• v.10 no.2
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• pp.125-138
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• 2020

Due to the development of camera technology, the cost of producing time-lapse video has been reduced, and time-lapse videos are being applied in many fields. Time-lapse video is created using images obtained by shooting for a long time at long intervals. In this paper, we propose a method to improve the quality of time-lapse videos monitoring the changes in plants. Considering the characteristics of time-lapse video, we propose a method of separating the desired and unnecessary objects and removing unnecessary elements. The characteristic of time-lapse videos that we have noticed is that unnecessary elements appear intermittently in the captured images. In the proposed method, noises are removed by applying a codebook background modeling algorithm to use this characteristic. Experimental results show that the proposed method is simple and accurate to find and remove unnecessary elements in time-lapse videos.