• The Journal of the Acoustical Society of Korea
• /
• v.24 no.2
• /
• pp.103-110
• /
• 2005

Providing adequate amount of spatial impression for spaciousness) has been known to be one of the most important design considerations for the good acoustics of rooms for music. and the measurement, of room acoustics using parameters. such as LEF and IACC, forms an essential part of such evaluation. However. it is unavoidable to use different transducers (figure of eight microphones. head and torso) for the measurement of each parameter and it tends to make the measurement procedure complicated. The Present work tried to provide a simpler way to measure these binaural room acoustic parameters including monaural ones with a single measurement system using both spatial information collected through a 5-channel microphone and a trained neural network. A computer simulation program, CATT-Acoustic V7.2. which allowed us to obtain exactly the same spatial information as a 5-channel microphone was used. since it requires quite a large amount of data for practical training of a neural network. Since each reflection has different energy. delay and direction, energy should be integrated properly. the concept of ray tracing method was applied inversely in this work. Also applying weightings according to the delay times was considered in this work. Finally, predicted results were compared with the measured data md their correlations were analyzed and discussed.

• Journal of Korea Technology Innovation Society
• /
• v.18 no.3
• /
• pp.416-443
• /
• 2015

The resource-based view (RBV) explains that the competitive advantage is mainly based on the resources which have strategic characteristics. Therefore, finding, developing and maintaining strategically valuable resources has been one of main research topics and a starting point in the corporate strategy structure in RBV. In this regards, attempts to recognize strategically valuable resources have been one of crucial issues in RBV researches. Especially, Barney's VRIO has been widely used as a practical tool for finding strategically valuable resources. However, empirical studies on VRIO framework's effectiveness have not been sufficiently implemented, and there has been no proven relation among the components of the VRIO so far. This is mainly because the concepts or definitions on core components of the VRIO - Value, Rareness, Inimitability, and Organization - are too comprehensively explained and measurements of each component cannot be easily quantified. Considering these, this paper presents empirical results of the relation between VRIO components and competitive advantage, and tests effectiveness of VRIO Framework with utilizing sufficient technology evaluation cases and financial statements of 2,252 technology based SMEs in Korea. As a result, the components of the VRIO have a positive influence on competitive advantage. The attributes of strategic resources - Value, Rareness, and Inimitability - have a statistically meaningful positive effect on organization, while organization has a positive effect on the competitive advantage serving as a parameter between the attributes of strategic resources and competitive advantage.

• Journal of KIISE
• /
• v.41 no.9
• /
• pp.652-665
• /
• 2014

Many important terminologies in biomedical text are expressed as abbreviations or acronyms. We newly suggest a semantic link topic model based on the concepts of topic and dependency link to disambiguate biomedical abbreviations and cluster long form variants of abbreviations which refer to the same senses. This model is a generative model inspired by the latent Dirichlet allocation (LDA) topic model, in which each document is viewed as a mixture of topics, with each topic characterized by a distribution over words. Thus, words of a document are generated from a hidden topic structure of a document and the topic structure is inferred from observable word sequences of document collections. In this study, we allow two distinct word generation to incorporate semantic dependencies between words, particularly between expansions (long forms) of abbreviations and their sentential co-occurring words. Besides topic information, the semantic dependency between words is defined as a link and a new random parameter for the link presence is assigned to each word. As a result, the most probable expansions with respect to abbreviations of a given abstract are decided by word-topic distribution, document-topic distribution, and word-link distribution estimated from document collection though the semantic dependency link topic model. The abstracts retrieved from the MEDLINE Entrez interface by the query relating 22 abbreviations and their 186 expansions were used as a data set. The link topic model correctly predicted expansions of abbreviations with the accuracy of 98.30%.

• The Journal of the Korea Contents Association
• /
• v.15 no.3
• /
• pp.184-191
• /
• 2015

Prostate ultrasound is used to diagnose prostate cancer, BPH, prostatitis and biopsy of prostate cancer to determine the size of prostate. BPH is one of the common disease in elderly men. Prostate is divided into 4 blocks, peripheral zone, central zone, transition zone, anterior fibromuscular stroma. BPH is histologically transition zone urethra accompanying excessive nodular hyperplasia causes a lower urinary tract symptoms(LUTS) caused by urethral closure as causing the hyperplastic nodule characterized finding progressive ambient. Therefore, in this study normal transition zone image for hyperplasia prostate and normal transition zone image is analyzed quantitatively using a computer algorithm. We applied texture features of GLCM to set normal tissue 60 cases and BPH tissue 60cases setting analysis area $50{\times}50pixels$ which was analyzed by comparing the six parameters for each partial image. Consequently, Disease recognition detection efficiency of Autocorrelation, Cluster prominence, entropy, Sum average, parameter were high as 92~98%.This could be confirmed by quantitative image analysis to nodular hyperplasia change transition zone of the prostate. This is expected secondary means to diagnose BPH and the data base will be considered in various prostate examination.

• Journal of Nutrition and Health
• /
• v.14 no.2
• /
• pp.59-70
• /
• 1981

The objective of this study is to induce the primary characteristics of phenylketonuria in infant rats during the first 2 weeks after birth. The critical biochemical parameter in the development of phenylketonuria is the elevation of plasma phenylalanine while tyrosine is maintained at a relatively low level. A PKU-like condition was induced in infant rats during the first 2 weeks after birth using a modification of our previously published procedure for the development of a temporary (1 to 3 days) PKU-like condition. Phenylalanine was administered by stomach intubation every 6 hours (starting at 6:00 a.m.) at a dose level of 400mg per kg body weight (after birth-day 2 thru 5) and 500mg per kg body weight (day 6 thru 14). Amethopterin was given at 0.00625 or 0.0125mg per kg body weight (day 3 thru 14) and p-chlorophenylalanine at 50 mg per kg body weight (day 5 thru 14) at 9:00 a.m. and 9:00 p.m. At the times measured (6,10 and 14 days) plasma phenylalanine/tyrosine (P/T) ratios were elevated from a normal value of the or less to values ranging from 6 to 15. During the second week after birth a staggering gait, abnormal stance and decreased social behavior were also observed. None of these PKU-like characteristics were apparent in the three control groups receiving (a) no phenylalanine or inhibitors, (b) phenylalanine alone, or (c) inhibitors alone. The establishment of these primary biochemical characteristics of phenylketonuria by stomach intubation of phenylalanine and a combination of low dose levels of enzyme inhibitors to infant rats provides an experimental system which should he valuable for extensive biochemical, histological and behavioral studies in phenylketonuria.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.7
• /
• pp.49-53
• /
• 2016

Recently, the use of signal compression methods to improve the efficiency of wireless networks have increased. In particular, the MPC system was used in the pitch extraction method and the excitation source of voiced and unvoiced to reduce the bit rate. In general, the MPC system using an excitation source of voiced and unvoiced would result in a distortion of the synthesis speech waveform in the case of voiced and unvoiced consonants in a frame. This is caused by normalization of the synthesis speech waveform in the process of restoring the multi-pulses of the representation segment. This paper presents an ACFBD-MPC (Amplitude Compensation Frequency Band Division-Multi Pulse Coding) using amplitude compensation in a multi-pulses each pitch interval and specific frequency to reduce the distortion of the synthesis speech waveform. The experiments were performed with 16 sentences of male and female voices. The voice signal was A/D converted to 10kHz 12bit. In addition, the ACFBD-MPC system was realized and the SNR of the ACFBD-MPC estimated in the coding condition of 8kbps. As a result, the SNR of ACFBD-MPC was 13.6dB for the female voice and 14.2dB for the male voice. The ACFBD-MPC improved the male and female voice by 1 dB and 0.9 dB, respectively, compared to the traditional MPC. This method is expected to be used for cellular telephones and smartphones using the excitation source with a low bit rate.

• Journal of Korean Society of Environmental Engineers
• /
• v.22 no.10
• /
• pp.1825-1832
• /
• 2000

Column experiments were conducted by using soil columns, to investigate feasibility and efficiency of in-situ ozone enhanced remediation for diesel-contaminated soil. The injection of gaseous ozone into soil column revealed the enhanced decomposition of ozone due to the catalytic reaction between ozone and metal (e.g., Fe, Mn etc.) oxides as evidenced by as much as 25 times shorter half-life of ozone in a sand packed column than in a glass beads packed column. Substantial retardation in the transport of and the consumption of ozone were observed in the diesel contaminated field soil and sand packed columns. After 16 hrs ozonation, 80% of the initial mass of diesel (as diesel range organic) concentration of $800{\pm}50mg/kg$, was removed under the conditions of the flow rate of 50mL/min and $6mg-O_3/min$. Whereas, less than 30% of diesel was removed in the case of air injection. Analysis of the residual TPH(total petroleum hydrocarbon) and selected 8 aliphatics of diesel compounds in the inlet and the outlet of the column confirmed that diesel nonselectively reacted with ozone and then shifted to lower carbon numbered molecules. Water content also was found to be an important parameter in employing ozone to the hydrocarbon-contaminated soil.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.8 no.4
• /
• pp.123-133
• /
• 2008

This study evaluated the runoff data collected at 12 stream gauge stations of the Chungjoo dam basin using the IHACRES model. Especially, the geomorphology-related parameters of the IHACRES model could be quantified base on the regionalization technique, which have also been applied many stream gauge stations of the Chungjoo dam basin. Summarizing the results is as follows. (1) The climate-related parameters of the IHACRES model c, $\tau_w{^0}$, and f are found to be estimated and used uniformly over the basin. (2) The geomorphology-related parameters of the IHACRES model $t_q,\;t_s,\;and\;v_s$ are found to be estimated by considering the geomorphological parameters like the basin area, channel length, channel slope, basin slope through the regionalization based on the regression analysis. (3) Using the climate-related parameters applied uniformly over the basin and the geomorphology-related parameters estimated based on the regionalization procedure for each stream gauge station, a total of 12 stream gauge stations have been evaluated with their stream flow measurements. As results, the Sanganmi and Youngwal 1 stream gauge stations have been found to make high quality flow data, but Youngwal, Baekokpo, and Panwoon stations low quality flow data. On the whole, 12 stream gauge stations considered show large differences with their data quality, so a plan for securing more consistent data quality should be prepared imminently.

• The Korean Journal of Pesticide Science
• /
• v.15 no.2
• /
• pp.218-229
• /
• 2011

Lepimectin is a insecticide agent. In order to register this new pesticide, the series of toxicity data on animal testing were reviwed to evaluate its hazards to consumers and to determine its acceptable daily intake. Lepimectin was mostly excreted by feces. It has low acute oral toxicity while it has no dermal, ocular irritation and skin sensitization (As the result of subchronic, chronic toxicity and carcinogenicity showed changes of hematology and clinical biochemistry parameter of serum and blood.). Two-generation reproduction toxicity, genotoxicity, carcinogenicity and prenatal development toxicity were not proven. Therefore, the ADI for Lepimectin is 0.02 mg/kg/ bw/day, based on the NOAEL of 2.02 mg/kg/ bw/day of two-years carcinogenic toxicity study in rats and applying an uncertainty factor of 100.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37B no.11
• /
• pp.1072-1081
• /
• 2012

For Ka-band satellite communication system, a new flexible payload technologies which can compensate rain attenuation have to be developed. The Ka-band satellite output power control technology enables to adjust downlink output power of satellite payload in Ka-band (19.8 ~ 22.2 GHz). In this paper, we introduce multi-beam antenna with multi-port amplifiers for Ka-band flexible output power allocation system. We have designed multi-beam antenna with array-fed reflector to form 8 beams on the Korean Peninsula. The target EIRP per beam is more than 59 dBW. The system is designed to present 6 dB boost beams for rainfall areas. Individual beams were optimized by the excited amplitude and phase of feed elements of the feed cluster. The multi-port amplifier(MPA) is one of effective approaches for flexible power allocation in combination with multi-beam antenna. In case of using MPA in multi-beam system, the inter-port isolation characteristic of MPA is important parameter to avoid interference among the output ports. In this paper, we propose a new MPA structure that consists of two $4{\times}4$ Buttler matrixes and phase/amplitude controllable power amplifier modules.