• 생태와환경
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• 제44권2호
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• pp.136-143
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• 2011

멸종위기종 돌상어 Gobiobotia brevibarba의 초기생활사에 대한 연구는 생물학적 특성 및 복원의 기초자료를 확보하기 위해 2010년 4월부터 6월까지 강원도 홍천군에서 성숙한 개체를 채집하여 난발생 및 초기생활사를 조사하였다. 채집된 성숙한 암컷과 수컷은 Ovaprim을 주사한 후 건식법으로 인공수정시켰다. 성숙란은 약한 접착성을 띤 투명한 회색난이었으며, 난경은 $1.24{\pm}0.07$ mm 였다. 수온 $23^{\circ}C$에서 수정 후 120시간 후에 부화하였으며, 부화 직후 전기자어는 전장 $5.5{\pm}0.29$ mm였다. 부화후 4일만에 난황을 모두 흡수하였으며 전장 $7.4{\pm}0.26$ mm로 성장하였고, 부화 후 15 일에는 전장 $9.9{\pm}0.72$ mm로 모든 지느러미 기조가 정수가 되어 치어기로 이행하였다. 부화 후 100 일 후에는 전장 $36.0{\pm}3.11$ mm로 체측반문과 외부형태가 성어와 유사한 모습을 보였다.

• 한국어류학회지
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• 제23권3호
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• pp.198-205
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• 2011

멸종위기어류 돌상어의 생물학적 특성 및 복원을 위한 기초자료를 확보하기 위하여 초기생활사를 2010년 4월부터 6월까지 강원도 홍천군에서 성숙한 개체를 채집하였다. 채집된 성숙한 암컷과 수컷은 Ovaprim을 주사한 후 건식법으호 인공 수정시켰다. 성숙란은 약한 접착성을 띤 투명한 회색난이었으며, 난경은 0.89${\pm}$0.04mm였다. 수온 23$^{\circ}C$에서 수정 후 107시간 만에 부화하였으며, 부화 직후 전기자어 크기는 전장 4.6${\pm}$0.16mm였다. 부화 후 4일에는 전장 6.1${\pm}$0.20mm로 난황을 모두 흡수하여 후기자어로, 부화 후 15일에는 전장 8.6${\pm}$0.67mm로 모든 지느러미 기조가 정수가 되어 치어기로 이행하였다. 부화 후 100일 후에 31.5${\pm}$3.32mm로 체측반문과 외부형태가 성어와 유사한 모습을 보였다.

• 한국측량학회지
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• 제30권6_2호
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• pp.673-680
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• 2012

Long-term GPS data analysis was performed in order to analyze the seasonal variation of tropospheric delay and the success rate of the ambiguity resolution. For this analysis, a total of 57 stations including 10 IGS stations in East Asia were processed together with double-differenced observables using Bernese GPS Software V5.0. The time span for this study ranges from 2002.0 to 2012.5 (10.5 years). The average baseline length is 339.0 km and the maximum reaches up to 2,000 km. The analysis is focused on two things: the annual variation of the tropospheric delay and the ambiguity resolution rate. The tropospheric delay is closely related to the weather condition, especially relative humidity, therefore it was estimated that the maximum would be in summer, while reaching its minimum in winter with the apparent seasonal variations. On the contrary, however, the success rate of the ambiguity resolution shows the opposite pattern: its maximum was in winter and minimum in summer. The fact seems to be induced by the surrounding conditions; that is, the trees thick with leaves near the GPS antenna interfere with GPS signals in summer. This seems to confirm partly that there is a distinct trend in the decreasing success rate since 2006 because the trees are growing every year. It is necessary to eliminate the factors that degrade the GPS quality and the tropospheric modeling for Korea needs to be studied further.

• 대한물리의학회지
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• 제8권3호
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• pp.387-395
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• 2013

PURPOSE: The purpose of the present study was to investigate the effect of the training using Pedalo equipment on balance function in post-stroke patients. METHODS: The present study was case-series. Ten post-stroke patients participated in the study. Participants performed the training using Pedalo equipment. The training using four Pedalo equipment lasted 30 minutes, 3 times a week for 6 weeks. Force platform, Berg Balance Scale(BBS), and Timed Up and Go(TUG) test were used to assess balance ability before and after training. RESULTS: After training using Pedalo equipment, there were significantly improved on path length and sway velocity of post-stroke patients in the both of eye open and - close conditions comparing with baseline. Also, on the BBS and TUG, there were significant improvements after training. CONCLUSION: The results of this study showed that the training using Pedalo equipment may be effective on improving the balance ability in the post-stroke patients. Through this study, we were able to confirm the potential of training using Pedalo equipment as an intervention in the rehabilitation of post-stroke patients.

• 한국통신학회논문지
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• 제21권10호
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• pp.2563-2578
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• 1996

In this paper, channel error characteristics are investigated to alleviate the channel error propagation problem of the digital TV transmission systems. First, error propagation problems, which are mainly caused by the inter-frame dependancy and variable length coding of the MPEG-2 baseline encoder, are intensively analyzed. Next, existing channel resilient schemes are systematically classified into two kinds of schemes; one for the encoder and the other for the decoder. By comparing the performance and implementation cost, the encoder side schemes, such as error localization, layered coding, error resilience bit stream generation techniques, are described in this paper. Also, in an effort to consider the parcticality of the real transmission situation, an efficient error detection scheme for a decoder system is proposed by employing a priori information of the bit stream syntas, checking the encoding conditions at the encoder stage, and exploiting the statistics of the image itself. Finally, subsequent error concealment technique based on the DCT coefficient recovery algorithm is adopted to evaluate the performance of the proposed error resilience technique. The computer simulation results show that the quality of the received image is significantly improved when the bit error rate is as high as 10$^{-5}$ .

• Nuclear Engineering and Technology
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• 제48권2호
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• pp.351-359
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• 2016

The Korean Prototype Gen-IV sodium-cooled fast reactor (PGSFR) is supposed to be loaded with a relatively-costly low-enriched U fuel, while its envisaged transuranic fuels are not available for transmutation. In this work, the U-enrichment reduction by improving the neutron economy is pursued to save the fuel cost. To improve the neutron economy of the core, a new reflector material, PbO, has been introduced to replace the conventional HT9 reflector in the current PGSFR core. Two types of PbO reflectors are considered: one is the conventional pin-type and the other one is an inverted configuration. The inverted PbO reflector design is intended to maximize the PbO volume fraction in the reflector assembly. In addition, the core radial configuration is also modified to maximize the performance of the PbO reflector. For the baseline PGSFR core with several reflector options, the U enrichment requirement has been analyzed and the fuel depletion analysis is performed to derive the equilibrium cycle parameters. The linear reactivity model is used to determine the equilibrium cycle performances of the core. Impacts of the new PbO reflectors are characterized in terms of the cycle length, neutron leakage, radial power distribution, and operational fuel cost.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 추계국제학술대회
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• pp.47-47
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• 2020

In this study, we aimed to study carnation italian ringspot virus (CIRV) in Erigeron annuus (L.) Pers. in Bonghwa County, Korea. The collected samples showed mosaic and malformation symptoms. To identify the virus species, we performed high-throughput sequencing, reverse transcription polymerase chain reaction, and cloning. The virus was confirmed to be an unreported species, and therefore we performed genome sequencing of the samples. The complete genome was 4,746 nucleotides in length. The CIRV contained five open reading frames (ORFs), and it showed the typical features of members of the genus Tombusvirus. Phylogenetic analyses revealed that ClRV isolates had the highest nucleotide identities with the CZ isolate (95.89%) from Korea. In recent years, these viruses have sporadically been reported in floral scent and medicinal plants. This research found the first natural host infected with CIRV, and provides baseline information to determine the correlation between weeds and crops.

• 대한의용생체공학회:의공학회지
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• 제17권2호
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• pp.235-240
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• 1996

The automated ECG diagnostic systems that are odd in hospitals have low performance of P-wave detection when faced with some diseases such as conduction block. So, the purpose of this study was the improvement of detection performance in conduction block which is low in P-wave detection. The first procedure was removal of baseline drift by subtracting the median filtered signal of 0.4 second length from the original signal. Then the algorithm detected R peak and T end point and cancelled the QRS-T complex to get'p prototypes'. Next step was magnification of P prototypes with dispersion and detection of'p candidates'in the magnified signal, and then extraction of contextual information concerned with P-waves. For the last procedure, the CIR was applied to P candidates to confirm P-waves. The rule base consisted of three rules that discriminate and confirm P-waves. This algorithm was evaluated using 500 patient's raw data P-wave detection perFormance was in- creased 6.8% compared with the QRS-T complex cancellation method without application of the rule base.

• 펄프종이기술
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• 제37권2호
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• pp.47-56
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• 2005

In technology of ink-jet coating, Image quality from correlation between paper and ink depends on the properties of printer and ink as well as those of paper material. Generally, According to the quality of ink that consists of colorants from 5 to 20 percent, It seems that absorption behavior of each ink is different. In this study, we studied to estimate the effects of dye and pigment ink on the absorption and printing properties using 2-type papers on the market and 3-type silica-based coated papers whose pore structure is different. Using the theory of contact angle to evaluate the absorption property, it was possible to measure the baseline length between paper and ink, volume of droplet as well as contact angle. Also, It was possible to calculate wetting energy(mN/m) and spreading coefficient(mN/m) using the surface tension of each ink. These measurements were available to estimate ink-jet qualities.

• Journal of Periodontal and Implant Science
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• 제51권1호
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• pp.30-39
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• 2021

Purpose: The present study was undertaken to examine whether periodontal probe visibility (PV) accurately reflects gingival thickness (GT) and to identify factors affecting PV using cluster and multivariate analyses. Methods: The clinical characteristics of the maxillary central incisors (n=90 subjects) were examined. Clinical photographs, sex, PV, probing depth, gingival width, papilla height, GT as measured with an ultrasonic device, and the ratio of crown width to crown length were recorded. Multivariate analysis, using multinomial baseline-category logistic regression, was used to identify factors predictive of PV. Cluster analysis was used to identify gingival biotypes. Results: In the multivariate analysis, sex was the only significant predictor of PV (odds ratio, 6.48). Two clusters of subjects were created based on morphometric parameters. The mean GT among cluster A subjects was significantly lower than that among cluster B subjects (P=0.015). No significant difference was found between cluster A and B subjects in terms of PV score (P=0.583). Conclusions: Periodontal PV was not associated with GT as measured directly using an ultrasonic device. Sex was a highly significant predictor of periodontal PV. GT was found to be correlated with morphological characteristics of the periodontium.