• Title/Summary/Keyword: NCB

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Surface Subsidence according to Progressive Collapse of Circular opening (원형공동의 점진적인 붕락에 따른 지표침하특성)

  • 지정배;김종우
    • Tunnel and Underground Space
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    • v.10 no.1
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    • pp.33-44
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    • 2000
  • In order to investigate the effect of progressive collapse of underground circular opening on surface subsidence, laboratory model tests were performed. The modelling materials were sand which has been used as KS standard. Six test models which had respectively different depths of openings were produced. Surface subsidence and horizontal displacements were measured according to progressive collapse of underground opening. Some subsidence prediction method such as NCB method, profile function method and influence function method were considered to predict the subsidence of sand models. The profile function method approximated by Gaussian error function was finally suggested as the most appropriate to sand models.

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A Study on the Improvement of Defense Codification System (국방보급목록제도 개선방안에 관한 연구)

  • 최석철;서호일
    • Journal of the Korea Institute of Military Science and Technology
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    • v.3 no.2
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    • pp.189-203
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    • 2000
  • This paper deals with the improvement of defense codification system for the items of defense supplies. We review other country's codification systems, their concept and trend of the systems for development, and then apply the ideas to our defense codification system. The proposal for improvement of defense codification system consists of three parts. The first one is the aspect of policy, the second one is the aspect of organization, and the last one is the aspect of operation. This paper will be contributed to the development of national codification system, and defense logistics management.

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Lamotrigine, an antiepileptic drug, inhibits 5-HT3 receptor currents in NCB-20 neuroblastoma cells

  • Kim, Ki Jung;Jeun, Seung Hyun;Sung, Ki-Wug
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.2
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    • pp.169-177
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    • 2017
  • Lamotrigine is an antiepileptic drug widely used to treat epileptic seizures. Using whole-cell voltage clamp recordings in combination with a fast drug application approach, we investigated the effects of lamotrigine on 5-hydroxytryptamine $(5-HT)_3$ receptors in NCB-20 neuroblastoma cells. Co-application of lamotrigine ($1{\sim}300{\mu}M$) resulted in a concentration-dependent reduction in peak amplitude of currents induced by $3{\mu}m$ of 5-HT for an $IC_{50}$ value of $28.2{\pm}3.6{\mu}M$ with a Hill coefficient of $1.2{\pm}0.1$. These peak amplitude decreases were accompanied by the rise slope reduction. In addition, $5-HT_3$-mediated currents evoked by 1 mM dopamine, a partial $5-HT_3$ receptor agonist, were inhibited by lamotrigine co-application. The $EC_{50}$ of 5-HT for $5-HT_3$ receptor currents were shifted to the right by co-application of lamotrigine without a significant change of maximal effect. Currents activated by 5-HT and lamotrigine co-application in the presence of 1 min pretreatment of lamotrigine were similar to those activated by 5-HT and lamotrigine co-application alone. Moreover, subsequent application of lamotrigine in the presence of 5-HT and 5-hydroxyindole, known to attenuate $5-HT_3$ receptor desensitization, inhibited $5-HT_3$ receptor currents in a concentration-dependent manner. The deactivation of $5-HT_3$ receptor was delayed by washing with an external solution containing lamotrigine. Lamotrigine accelerated the desensitization process of $5-HT_3$ receptors. There was no voltage-dependency in the inhibitory effects of lamotrigine on the $5-HT_3$ receptor currents. These results indicate that lamotrigine inhibits $5-HT_3$-activated currents in a competitive manner by binding to the open state of the channels and blocking channel activation or accelerating receptor desensitization.

Comparative Study on the Educational Use of Home Robots for Children

  • Han, Jeong-Hye;Jo, Mi-Heon;Jones, Vicki;Jo, Jun-H.
    • Journal of Information Processing Systems
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    • v.4 no.4
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    • pp.159-168
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    • 2008
  • Human-Robot Interaction (HRI), based on already well-researched Human-Computer Interaction (HCI), has been under vigorous scrutiny since recent developments in robot technology. Robots may be more successful in establishing common ground in project-based education or foreign language learning for children than in traditional media. Backed by its strong IT environment and advances in robot technology, Korea has developed the world's first available e-Learning home robot. This has demonstrated the potential for robots to be used as a new educational media - robot-learning, referred to as 'r-Learning'. Robot technology is expected to become more interactive and user-friendly than computers. Also, robots can exhibit various forms of communication such as gestures, motions and facial expressions. This study compared the effects of non-computer based (NCB) media (using a book with audiotape) and Web-Based Instruction (WBI), with the effects of Home Robot-Assisted Learning (HRL) for children. The robot gestured and spoke in English, and children could touch its monitor if it did not recognize their voice command. Compared to other learning programs, the HRL was superior in promoting and improving children's concentration, interest, and academic achievement. In addition, the children felt that a home robot was friendlier than other types of instructional media. The HRL group had longer concentration spans than the other groups, and the p-value demonstrated a significant difference in concentration among the groups. In regard to the children's interest in learning, the HRL group showed the highest level of interest, the NCB group and the WBI group came next in order. Also, academic achievement was the highest in the HRL group, followed by the WBI group and the NCB group respectively. However, a significant difference was also found in the children's academic achievement among the groups. These results suggest that home robots are more effective as regards children's learning concentration, learning interest and academic achievement than other types of instructional media (such as: books with audiotape and WBI) for English as a foreign language.

Internal Fixation of Proximal Humerus Fracture with Polyaxial Angular Stable Locking Compression Plate in Patients Older Than 65 Years (65세 이상의 상완골 근위부 골절 환자에서 다축 각안정 잠김 압박 금속판을 이용한 내고정술)

  • Lee, Ki-Won;Choi, Young-Joon;Ahn, Hyung-Sun;Kim, Chung-Hwan;Hwang, Jae-Kwang;Kang, Jeong-Ho;Choo, Han-Ho;Park, Jun-Seok;Kim, Tae-Kyung
    • Clinics in Shoulder and Elbow
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    • v.15 no.1
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    • pp.25-31
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    • 2012
  • Purpose: The clinical and radiographic outcomes of the internal fixation, which were executed on patients over the age of 65 with proximal humerus fracture by using a polyaxial angular stable locking compression plate (Non-Contact-Bridging proximal humerus plate, Zimmer, Switzerland, NCB), were evaluated. Materials and Methods: Thirty two patients over the age of 65 among the proximal humerus fracture treated with NCB plate, between August 2007 and January 2011, were chosen as the subjects. The average age of patients was 71 years, and the average postoperative follow-up period was 11.5 months. The fractures included 14 two-part and 18 three-part fractures. The clinical results were evaluated, using the visual analog scale (VAS) score and the Constant score. The radiological results were evaluated by time to union and Paavolainen method, which measures the neck shaft angle. Results: At the last follow-up examination, the mean VAS score was 3 points and the mean Constant score was 64.5 points, with bone union achieved after the average of 16.2 weeks following the surgery in all the cases. The mean neck shaft angle was 125.9 and 24 cases had good results, while 8 cases had fair results by Paavolainen method, at the last follow-up. There were 1 case of delayed union and cerclage wire failure, and 3 cases of subacromial impingement. There were no complications, such as loss of reduction, nonunion, screw loosening, or avascular necrosis of the humeral head. Conclusion: Internal fixation, using a NCB plate, was considered to be an effective surgical method in treating proximal humerus fracture in the elderly patients, on whom the fixation of the fracture and maintenance of reduction are difficult.

Palaeomagnetism of the Okchon Belt, Korea: Paleozoic Rocks in Yemi Area (옥천대에 대한 고자기 연구: 예미지역 고생대 지층의 잔류자기)

  • 김인수;김성욱;최은경
    • Economic and Environmental Geology
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    • v.34 no.4
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    • pp.355-373
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    • 2001
  • Palaeomagnesim of Paleozoic Tuwibong Type Sequence in Yemi area was studied with a total of 256 core-samples collected from 23 sites. The study area (geographical coordinates: 37.l8$^{\circ}$N, l28.610E) is located between Taebaek and Yongwol belonging to the northeastern part of the Okchon Belt. Thermal cleaning was a most effective method to extract stable characteristic remanent magnetization (ChRM) direction, even though AF cleaning also worked on some specimens. Mean ChRM direction of the Cambrian Hwajol Formation was different from the present-day field direction and showed maximum clustering (max. k value) at 100% bedding-tilt correction. However, it could not pass the fold test. Ordovician Makkol and Kosong Limestones as well as Permian Sadong and Kobangsan Formations have very weak NRM, and were remagnetized into the present-day field direction. ChRM directions from the Carboniferous Hongjom Formation passed both fold and reversal tests. IRM experiments and blocking temperature spectrum indicate that both magnetite and haematite are carrier of the primary magnetization. Palaeomagnetic pole position from the Carboniferous Hongjom Formation is very similar to that of contemporary North China Block (NCB) suggesting that the study area was a part of, or located very near to, the NCB during Carboniferous.

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Reformation of Naphtha Cracking Bottom Oil for the Preparation of Carbon Fiber Precursor Pitch (탄소섬유용 프리커서 피치를 제조하기 위한 나프타 분해 잔사유의 개질)

  • Kim, Myoung Cheol;Eom, Sang Yong;Ryu, Seung Kon;Edie, Dan D.
    • Korean Chemical Engineering Research
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    • v.43 no.6
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    • pp.745-750
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    • 2005
  • Naphtha cracking bottoms(NCB) oil was reformed by varying the heat treatment temperature, treatment time, and nitrogen flow rate in preparation of precursor pitch for isotropic pitch-based carbon fibers and activated carbon fibers. The reformed pitches were investigated in the yield, softening point, elementary analysis, and molecular weight distribution, and then the precursors reformed were melt spun to certify the optimum reforming conditions. The optimum precursor pitch was prepared when the NCB oil was reformed at $380^{\circ}C$, 3 h and 1.25 vvm $N_2$, and it's the softening point was around $240^{\circ}C$. The reforming resulted in product yield of 21 wt%. The C/H mole ratio of the precursor pitch increased from 1.07 to 1.34, the aromaticity increased from 0.85 to 0.88. The insolubles in benzene and quinoline were 30.0 wt% and 1.5 wt%, respectively. The spinning temperature was about $50^{\circ}C$ higher than the softening point. The molecular weights of the precursor components were distributed from 250 to 1250, and 80% of them were in the range of 250 to 700.

A Study on the Car Audio Sound Quality Enhancement under Vehicle Noise and Its Subjective Evaluation (차량 주행소음을 고려한 자동차 오디오 음질 개선 및 주관적 음질평가 연구)

    • The Journal of the Acoustical Society of Korea
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    • v.18 no.8
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    • pp.108-115
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    • 1999
  • In this study we suggested a digital filter method to enhance car audio sound quality against the sound distortion due to cabin's acoustic characteristics and car driving noises. The digital filters designed were based on the characteristics on car driving noises and cabin acoustic characteristics. Car driving noises were analyzed by two ways; one is an objective method, octave band frequency analysis method. The other is a subjective method; sensory evaluation method, NCB method. On these results, seven sets of modified coefficients of eleven band digital filters were obtained. To find optimum audio sound quality among nine sound samples filtered by designing seven types of digital filters, which were mixed car driving noises at 100km/h, subjective evaluation method was used, paired comparison method; Scheffe' seven point method.

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The Effect of Atmospheric Flow Field According to the Urban Roughness Parameter and the Future Development Plan on Urban Area (도심 실제 거칠기 적용과 장래 도심 개발계획에 따른 국지 기상장 변화 수치 모의)

  • Choi, Hyun-Jung;Lee, Hwa-Woon;Kim, Min-Jung
    • Journal of Environmental Science International
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    • v.19 no.6
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    • pp.703-714
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    • 2010
  • In this study, we analyzed the impact of orographic and thermal forcing on the atmospheric flow field over the urban metropolitan areas on urban artificial buildings and future development plan. Several numerical experiments have been undertaken in order to clarify the impacts of the future development plan on urban area by analyzing practical urban ground conditions, we revealed that there were large differences in the meteorological differences in each case. The prognostic meteorological fields over complex areas of Seoul, Korea are generated by the PSU/NCAR mesoscale model(MM5). we carried out a comparative examination on the meteorological fields of topography and land-use that had building information and future development plan. A higher wind speed at daytimes tends to be forecasted when using new topography and land use data that have a high resolution with an appropriate limitation to the mixing height and the nocturnal boundary layer(NCB). During nighttime periods, since radiation cooling development is stronger after development plan, the decreased wind speed is often generated.