• Speech Sciences
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• v.10 no.4
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• pp.125-136
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• 2003

Speech coding techniques have been studied to reduce the complexity and bit rate but also to improve the sound quality. CELP type vocoder, has used as a one of standard, supports the great sound quality even low bit rate. In this paper, the preprocessing of input speech to reduce the bit rate is the different with the conventional vocoder. The different kinds of parameter are used for the preprocessing so this paper is compared with theses parameters for finding the more appropriate parameter for the vocoder. The parameters are used to synthesize the speech not to encode or decode for coding technique so we proposed the simple algorithm not to have the influence on the processing time or the computation time. The parameters in used the preprocessing step are speaking rate, duration and PSOLA technique.

• Mass Spectrometry Letters
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• v.12 no.1
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• pp.26-30
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• 2021

The impurity concentration is a crucial parameter for semiconductor thin films. Evaluating the impurity distribution in silicon thin film is another challenge. In this study, we have investigated the doping concentration of boron in silicon thin film using time of flight secondary ion mass spectrometry in dynamic mode of operation. Boron doped silicon film was grown on i) p-type silicon wafer and ii) borosilicate glass using hot wire chemical vapor deposition technique for possible applications in optoelectronic devices. Using well-tuned SIMS measurement recipe, we have detected the boron counts 101~104 along with the silicon matrix element. The secondary ion beam sputtering area, sputtering duration and mass analyser analysing duration were used as key variables for the tuning of the recipe. The quantitative analysis of counts to concentration conversion was done following standard relative sensitivity factor. The concentration of boron in silicon was determined 1017~1021 atoms/㎤. The technique will be useful for evaluating distributions of various dopants (arsenic, phosphorous, bismuth etc.) in silicon thin film efficiently.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.1
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• pp.129-135
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• 2008

The combined sewer overflows(COSs) which enters to river are involved with water pollution of rivers. Therefore, the standard capacity should be decided in proper standard considering water pollution density and characteristic of outflow. But in domestic, the standard capacity is not considered the characteristics of rainfall-outflows and is applied uniformly in all areas. The standard is triple of a maximum amount of sewage per one hour ; 3Q. The outflow of 3Q enters to sewage treatment plant and the overflows enter to river. In this study, a standard rainfall is estimated to determine the capacity of intercepting sewer by statistical analysis of rainfall data and it is considered about the regional characteristic of the rainfall-outflow. The standard rainfall is analyzed through the data of Seoul. In the result the standard rainfall was 6.76mm of 4hr duration. The rainfall-outflows and CSOs are analyzed using SWMM(Storm Water Management Model).

• Korean Journal of Construction Engineering and Management
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• v.16 no.1
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• pp.35-43
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• 2015

It is important to have enough design and construction duration for infrastructure projects. However, recent water resource project in Korea shows several problems caused by their fast-tract schedule. National Audit Committee report several water resource projects have quality problems caused by insufficient project duration. Especially, water resource projects such as dam and water pipeline construction should have proper time to secure their structure quality. Normal project duration for these projects should be estimated based on previous similar projects' historical data analysis. However there is no standard model which can estimate normal project duration for water resource projects in Korea. There are several normal project duration estimation models for building project developed by public(LH) and private construction companies. However, there is no proper model for water resource projects. So, this study developed normal project duration model for dam and water pipeline projects using historical data and show application of models.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.5
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• pp.770-778
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• 2010

To establish the fundament for EBM of Traditional Korean Medicine, the papers on Pyeongwi-san (Pingwei-san) frequently used in medical institutions of Traditional Korean Medicine were analyzed through researching domestic and international papers. The papers were classified by the registration of domestic or international journals, the year of publishment, experimental fields and the kinds of studies on biological activities. Of total 518 papers on Pyeongwi-san (Pingwei-san), 32 volumes were selected according to selection creteria. 20 volumes were published in domestic journals, 11 in Chinese journal and 1 in Japanese journal. The papers on instrumental analyses reported the quantification of standard compounds of herbal medicines in Pyeongwi-san (Pingwei-san) using HPLC, GC-MS. The papers on biological activities of Pyeongwi-san (Pingwei-san) showed improvement of gastrointestinal activity and water-electrolyte metabolism, immune regulation, anti-oxidant, anti-inflammatory, analgesic, anti-convulsant activities, hypnotic duration, blood pressure regulation, hepatic protection, congestive heart failure, anti-cancer activities. Further studies including gastrointestinal activity need to be preceeded to establish the fundament for EBM of Pyeongwi-san (Pingwei-san).

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.3
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• pp.230-237
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• 2008

Recently, lots of interest and competition in developments related to the autonomous-vehicle robot are being further increased. However, the absence of the standard architectures for effectively controlling the autonomous-vehicle robot led to many difficulties such as the long duration of development and the uncompatibility with other autonomous-vehicle robots. Accordingly, we implemented a mobile autonomous-vehicle robot system based on JAUS standard architecture. The mobile robot communicates with the remote-control system by using wireless LAN UDP/IP JAUS command massages. Its effectiveness is showed through the experimental results related to the navigation of implemented robot.

• Geomechanics and Engineering
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• v.31 no.6
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• pp. 583-597
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• 2022

Frost heave can cause uneven ground uplift that may damage geo-infrastructure. To assist damage-prevention strategies, standard frost heave testing methods and frost susceptibility criteria have been established and used in various countries. ASTM International standard testing method is potentially the most useful standard, as abundant experimental data have been acquired through its use. ASTM International provides detailed recommendations, but the method is expensive and laborious because of the complex testing procedure requiring a freezing chamber. A simple frost heave testing method using a temperature-controllable cell has been proposed to overcome these difficulties, but it has not yet been established whether a temperature-controllable cell can adequately replace the ASTM International recommended apparatus. This paper reviews the applicability of the ASTM International testing method using the temperature-controllable cell. Freezing tests are compared using various soil mixtures with and without delivering blow to depress the freezing point (as recommended by ASTM International), and it is established that delivering blow does not affect heave rate, which is the key parameter in successful characterization of frost susceptibility. As the freezing temperature decreases, the duration of supercooling of pore water shortens or is eliminated; i.e., thermal shock with a sufficiently low freezing temperature can minimize or possibly eliminate supercooling.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.5B
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• pp.475-481
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• 2011

The TMDL standard flow as applying watershed management regime uses the average low flow of past 10 years. Moreover, the TMDL implementation assessment has been enforced through management of pollutant load satisfied objective water quality. Even though the present allocation and management through averaged low flow are still convenient, they are not enough to solve ultimate goals of watershed management to keep up recovery of water body. To maintain the same water quality concentration, the standard flow is required to consider total discharge in management plan which helps to keep healthy ecosystem. In view of this, it would be possible to approach reasonable assessment by reflecting variably changeable discharge from precipitation-streamflow relation and the TMDL standard establishment considering artificial regulated flow. Therefore, this study attempts to develop the TMDL method using Load Duration Curve (LDC) and Streamflow-Load Rating Curve (QLRC) considering total discharge and finds drawbacks with solutions as applying on Nakdong river TMDL unit watershed. Finally, this research evaluates possibility of application on pollutant load allocating and implementation assessment in Korea.

• Water for future
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• v.10 no.1
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• pp.39-51
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• 1977

The purpose of this study is to make "The Rainfall Frequency Atlas in Korea" by the analytical method with new hydrological concepts. In this study, all of the rainfall datas in Korea was used for surveying of the basic data, and so we can get 103 sites for annual rainfall data and 100 sites for the max. in a day that are suitable to the purpose of the study. The above data groups are possible to estimate the normal standard period by the moving average method with $\pm$5% of significance level of variance ratio between the max. and min. moving average and arithmetic mean, but it may be impossible to study until 1990's for the short duration under 18-hr because the sites, having the short duration data, are only 12. The results of this study are as follows; 1. The normal standard period estimated by the moving average method is 20 year with $\pm$5% of significance level of variance ratio, and 30 year with$\pm$2-3%. 2. For the annual and max. rainfall in a day, it is possible to make the rainfall frequency atlas with 30normal standard period, but it may be impossible until 1990's for short duration. 3. "Y-k method" developed by writer is best suitable in the rainfal frequency analysis in Korea because of its convenience and reduction in the amount of calculation compared with other methods. 4. To improve the utilization of the rainfall frequency atlas, the larger-sized and the more detailed iso-precipitation atlas must be drawn.atlas must be drawn.

• Water for future
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• v.19 no.3
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• pp.249-258
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• 1986

The purpose of this study is to estimate the PMP frequency factor for evaluation of the Probable Maximum Precipitation (PMP) in Korea. The value of PMP is the criterion of the determination of design rainfall in Planning and designing hydraulic structures, and water resources management. To obtain the object, 12 key stations were selected in which have the automatic rain0recording paper of 20 years, and the annual maximum rainfall values were calculated for each 7 durations(10 min., 1, 2, 4, 6, 12, 24 hr.). The statistics(mean, standard deviation)were estimated, and diagram which shows the relationship between mean annual maximum rainfall($$) and frequency factor for each durations were drawn. PMP was estimated by statistical method using the PMP frequency factor obtained from the diagram and statistics($$, Sn). The PMP-Duration Equation was derived from the envelope curve in order to obtain the PMP for an arbitrary duration. The isohyetal map of 24 hours PMP and PMP. DAD curve for the whole of Korea were drawn in accordance with the point PMP values.