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The Evaluation of Non-Destructive Formulas on Compressive Strength Using the Reliability Based on Probability (확률 기반의 신뢰도를 이용한 비파괴 압축강도 추정식 평가)

  • Park, Jin-Woo;Choo, Jin-Ho;Park, Gwang-Rim;Hwang, In-Baek;Shin, Yong-Suk
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.19 no.4
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    • pp.25-34
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    • 2015
  • Proposed equation is used many time in calculation of concrete compressive strength using the non-destructive testing at precision safety diagnosis. Most of proposed equation is suggested in abroad and have an error to estimate concrete compressive strength in the domestic. Therefor, proposed equation is low reliability to estimate concrete compressive and it has a significant effect in reliability of precision safety diagnosis. Nevertheless, It is possible to increase the reliability through a number of experiments from this problem that occurs in some localized part. This paper is proposed assessment formula of reliability related core compressive strength to increase the reliability. It is verified that reliability of proposed assessment formula is useful by probabilistic techniques. It is compared with each graphs of concrete compressive strength of proposed equation. It has been found that the present methods are very efficient.

Stiffness effect of fitting interference for a shrunk rotor (열박음 로터에서 간섭량의 강성 효과)

  • 김영춘;박희주;박철현;김경웅
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.319-324
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    • 2003
  • In general industrial rotating machinery is operated under 3,600 rpm as rotating speed and designed to have critical speed that is above operating speed. So, there was no problem to operate rotating machine under critical speed. But nowadays, they should be operated more than the frist critical speed as usual with the trend of high speed, large scale and hish precision in industries. In case of the large rotor assembly as the trend of large scale, using fitting method of disk or cylinder on shaft is rising for the convenience of assembly and cutting down of manufacturing cost. The shrink fitting is used to assemble lamination part on shaft for manufacturing of rotor of motor or generator in many cases and also is widely used for other machinery. In rotating system, which is compose of rotor and bearing, the critical speed is determined from inertia and stiffness for the rotor and bearings. In case of fitting assembly, analysis and design of the rotor is not easy because the rotor stiffness is determined depend on a lot of factors such as shaft material/dimension, disk material/dimension and assembled interference etc. Therefore designer who makes a plan for hish-speed rotating machine should design that the critical speed is located out of operating range, as dangerous factors exist in it. In order to appropriate design, an accurate estimation of stiffness and damping is very important. The stiffness variation depend on fitting interference is a factor that changes critical speed and if it's possible to estimate it, that Is very useful to design rotor-bearing system. In this paper, the natural frequency variation of the rotor depends on fitting interference between basic shaft and cylinder is examined by experimentation. From the result, their correlation is evaluated quantitatively using numerical analysis that is introduced equivalent diameter end the calculation criteria is presented for designer who design fitting assembly to apply with ease for determination of appropriate interference.

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AKT-targeted anti-inflammatory activity of Panax ginseng calyx ethanolic extract

  • Han, Sang Yun;Kim, Juewon;Kim, Eunji;Kim, Su Hwan;Seo, Dae Bang;Kim, Jong-Hoon;Shin, Song Seok;Cho, Jae Youl
    • Journal of Ginseng Research
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    • v.42 no.4
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    • pp.496-503
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    • 2018
  • Background: Korean ginseng (Panax ginseng) plays an anti-inflammatory role in a variety of inflammatory diseases such as gastritis, hepatitis, and colitis. However, inflammation-regulatory activity of the calyx of the P. ginseng berry has not been thoroughly evaluated. To understand whether the calyx portion of the P. ginseng berry is able to ameliorate inflammatory processes, an ethanolic extract of P. ginseng berry calyx (Pg-C-EE) was prepared, and lipopolysaccharide-activated macrophages and HEK293 cells transfected with inflammation-regulatory proteins were used to test the anti-inflammatory action of Pg-C-EE. Methods: The ginsenoside contents of Pg-C-EE were analyzed by HPLC. Suppressive activity of Pg-C-EE on NO production, inflammatory gene expression, transcriptional activation, and inflammation signaling events were examined using the Griess assay, reverse transcription-polymerization chain reaction, luciferase activity reporter gene assay, and immunoblotting analysis. Results: Pg-C-EE reduced NO production and diminished mRNA expression of inflammatory genes such as cyclooxygenase-2, inducible NO synthase, and tumor necrosis factor-${\alpha}$ in a dose-dependent manner. This extract suppressed luciferase activity induced only by nuclear factor-${\kappa}B$. Interestingly, immunoblotting analysis results demonstrated that Pg-C-EE reduced the activities of protein kinase B (AKT)1 and AKT2. Conclusion: These results suggest that Pg-C-EE may have nuclear-factor-${\kappa}B$-targeted anti-inflammatory properties through suppression of AKT. The calyx of the P. ginseng berry is an underused part of the ginseng plant, and development of calyx-derived extracts may be useful for treatment of inflammatory diseases.

A component-based construction process control system for increasing modifiability (변경 용이성 증대를 위한 컴포넌트 기반의 건설공정관리시스템)

  • Kim, Eui-Ryong;Kim, Sin-Ryeong;Kim, Young-Gon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.6
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    • pp.303-309
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    • 2015
  • The construction process and safety management are an important means of the total projects for the decision-making. As an important management tool of cost, resources and risks of the project, the analysis and evaluations are recorded as an important asset of company. Also, it has become a safety device that could reduce risk factors repeatedly by the decision-making methods for the future similar projects. Component-based software, by reusing the useful part, which was prepared without newly developing all that, by building a new software product, the long-term continuous/steady through the provision of a component-based software, by securing a sales base, it should be the development and supply a wide range of applications. In this paper, we propose the construction process control systems for increasing modifiability of process creation and modification for business efficiency in accordance with the diverse trends in the construction process as a low-cost niche through a component-based software supplier to solve these problems.

우리나라 S/W 벤처기업의 경영현황

  • 한계섭;손성호
    • Proceedings of the Korea Association of Information Systems Conference
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    • 2000.11a
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    • pp.26-31
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    • 2000
  • It is said that the focus of managing venture business is currently moving from technology competition to management competition. By the way, the software venture business(SVB) has some weak points in its structural composition and itematization and no professional personnel in other several sections except technology development section. In addition, such basic functions as technology and R & D, finance and accounting, marketing required to the management of business are concentrated on only one man, its representative director. Therefore, this study aims to provide the basic data useful to the establishment of governmental policy in information and communication, to the rearing of the SVB by a local government related to the software, and to the administration of SVB by investigating the actual conditions. This study attempts to examine the literature on venture business and software industry, and its management with a questionnaire about the actual conditions of managing the SVB. The questionnaire is given to 527 local enterprises belonging to the Software Industry Association and to 171 enterprises in the Software Center. This study compromises the characteristics of the SVB, the actual conditions of its technology and R & D, finance and accounting, and marketing. The characteristics of the SVB are classified into categories such as the stage of its growth(the stage of its seed and start-up, the stage of tis development and growth, the stage of its stability and maturity) and the main business(the system integration, the software development for contract, the package software development service, the software-related service). Additionally, the study attempts to analyze positively the actual condition of its management after classified by the areas of business profile, its general management, its technology development, its finance and accounting, and its marketing The result of this study is found that the SVB has a lot of troubles in part of marketing and finance & accounting activity as well as general management. The SVB realizes the importance of the technology development rather than that of management activity including marketing activity. So we expect this study can assist the SVB to establish the business guidelines for own management plans.

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The Usefulness of Sural/Ulnar Amplitude Ratio in the Diagnosis of Early stage of Diabetic Polyneuropathy (초기 당뇨병성 다발신경병증에서 비복/척골 감각신경활동전위 진폭 비의 진단적 유용성)

  • Chang, Young-Hee;Roh, Hakjae;Ahn, Moo-Young;Moon, Hee Soo;Bae, Jong-Seok;Kim, Byoung Joon
    • Annals of Clinical Neurophysiology
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    • v.5 no.1
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    • pp.34-38
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    • 2003
  • Backgrounds and Objectives: In the length-dependent axonal polyneuropathy like diabetic polyneuropathy (DPN), the distal part of the longer axons are affected earlier. In cases of minimal distal axonal changes, nerve conduction studies (NCS) are frequently normal. If sural nerve is affected in the early stage of DPN, supportive parameters to detect the early axonal degeneration may be helpful. We investigated whether the sural/ulnar SNAP amplitude ratio (SUAR) may be a more sensitive indicator than sural amplitude alone in the diagnosis of early diabetic polyneuropathy. Methods: We analyzed medical records and electrophysiological studies of 141 patients with DM and 30 healthy subjects. The patients with early stage of DPN were defined as those having symptoms of neuropathy and normal NCS findings among the patients with DM. We compared SUAR between 57 patients with early stage of DPN and 71 agematched control subjects. Results: Fifty seven patients had an average SUAR of 0.8, compared to that of 1.1 in the 71 normal controls. The SUAR of less than 0.9 was supplementary predictor of axonal polyneuropathy, with the best balance of sensitivity and specificity (70%). The SUAR did not vary significantly with age, height or duration of DM. Conclusions: We conclude that the SUAR is a useful electrodiagnostic indicator to detect early stage of DPN.

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Changes in Sensory Function After Transcranial Direct Current Stimulation on Primary Motor Cortex Area

  • Min, Dong-Ki
    • Physical Therapy Korea
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    • v.21 no.4
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    • pp.1-8
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    • 2014
  • Transcranial direct current stimulation (tDCS) is a neuromodulatory technique that delivers low-intensity direct current to cortical areas, thereby facilitating or inhibiting spontaneous neuronal activity. This study was designed to investigate changes in various sensory functions after tDCS. We conducted a single-center, single-blinded, randomized trial to determine the effect of a single session of tDCS with the current perception threshold (CPT) in 50 healthy volunteers. Nerve conduction studies were performed in relation to the median sensory and motor nerves on the dominant hand to discriminate peripheral nerve lesions. The subjects received anodal tDCS with 1 mA for 15 minutes under two different conditions, with 25 subjects in each groups: the conditions were as follows tDCS on the primary motor cortex (M1) and sham tDCS on M1. We recorded the parameters of the CPT a with Neurometer$^{(R)}$ at frequencies of 2000, 250, and 5 Hz in the dominant index finger to assess the tactile sense, fast pain and slow pain, respectively. In the test to measure CPT values of the M1 in the tDCS group, the values of the distal part of the distal interphalangeal joint of the second finger statistically increased in all of 2000 Hz (p=.000), 250 Hz (p=.002), and 5 Hz (p=.008). However, the values of the sham tDCS group decreased in all of 2000 Hz (p=.285), 250 Hz (p=.552), and 5 Hz (p=.062), and were not statistically significant. These results show that M1 anodal tDCS can modulate sensory perception and pain thresholds in healthy adult volunteers. The study suggests that tDCS may be a useful strategy for treating central neurogenic pain in rehabilitation medicine.

Multiple Model Fuzzy Prediction Systems with Adaptive Model Selection Based on Rough Sets and its Application to Time Series Forecasting (러프 집합 기반 적응 모델 선택을 갖는 다중 모델 퍼지 예측 시스템 구현과 시계열 예측 응용)

  • Bang, Young-Keun;Lee, Chul-Heui
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.1
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    • pp.25-33
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    • 2009
  • Recently, the TS fuzzy models that include the linear equations in the consequent part are widely used for time series forecasting, and the prediction performance of them is somewhat dependent on the characteristics of time series such as stationariness. Thus, a new prediction method is suggested in this paper which is especially effective to nonstationary time series prediction. First, data preprocessing is introduced to extract the patterns and regularities of time series well, and then multiple model TS fuzzy predictors are constructed. Next, an appropriate model is chosen for each input data by an adaptive model selection mechanism based on rough sets, and the prediction is going. Finally, the error compensation procedure is added to improve the performance by decreasing the prediction error. Computer simulations are performed on typical cases to verify the effectiveness of the proposed method. It may be very useful for the prediction of time series with uncertainty and/or nonstationariness because it handles and reflects better the characteristics of data.

A Design and Implementation on Ontology for Public Participation GIS (시민참여형 GIS를 위한 온톨로지 설계 및 구현)

  • Park, Ji-Man
    • Journal of the Korean Geographical Society
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    • v.44 no.3
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    • pp.372-394
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    • 2009
  • This study investigates the ontology-based public participation GIS(PPGIS). The major reason that ontology-based GIS has attracted attention in semantic communication in recent year is due to the wide availability of geographical variable and the imminent need for turning such recommendation into useful geographical knowledge. Therefore, this study has been focused on designing and implementing the pilot tested system for public participation GIS. The applicability of the pilot tested was validated through a simulation experiment for history tourism in Guri city Gyeongi-do, Focused on the methodology, the life cycle model which involves regional statues and user recognition, can be viewed as an important preprocessing step(specification, conceptualization, formalization, integration and implementation) for recommended geographical knowledge discovery by axiom. Focusing on practicality, ontology in this study would be recommended for geographical knowledge through reasoning. In addition, ontology-based public participation GIS would show integration epistemological and ontological approach, and be utilized as an index which is connected with semantic communication. The results of the pilot system was applied to the study area, which was a part of scenario. The model was carried out using axiom of logical constraint in the meaning of human-activity.

Analysis on Momentary Voltage Dips with the Interconnection Operation of Utility-interactive Cogneration Systems Considering Their Generator Type (발전기 형태를 고려한 열병합발전시스템의 배전계통 연계운전시의 순시전압변동 해석)

  • 최준호;김재철
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.14 no.4
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    • pp.23-30
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    • 2000
  • Cogeneration systems are seen as a significant innovation for dispersed energy generation since they are both environmentally friendly and has comparatively high degrees of efficiency. It is especially suited for the decentralized provision of electricity and heat. However, it causes operational problems such as voltage regulation, voltage variation, protection and safety. Especially, it is expected that the interconnection/disconnection operation of cogeneration system has an effect on distribution voltage regulation and variation. Recently, with the increased use of customer-owned computers and other sensitive electronic equipment, electric power quality has become an important concerns. Therefore, the voltage quality problems with cogeneration system should be investigated because the voltage quality is an important part of electrical power quality. In this paper, the momentary voltage dips associated with the interconnection/disconnection operation of cogeneration system are analyzed, including restraint solutions at the customer level. In addition, the unit capacity of cogeneration systems per feeder are evaluated from the view point of momentary voltage variations. The results of this paper are useful analysis data for interconnection standards/guidelines of cogeneration systems and dispersed generation (DG)

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