• 제목/요약/키워드: positive real function

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Suitability of denervated muscle flaps as recipient sites for pancreatic islet cell transplantation

  • Park, Jong-Lim;Kim, Taewoon;Kim, Baek-Kyu
    • Archives of Plastic Surgery
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    • 제48권1호
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    • pp.133-143
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    • 2021
  • Background Extensive research has been conducted on islet transplantation as a possible cure for diabetes. Islet transplantation in the liver via the portal vein has shown remarkable results, but numerous other recipient sites are currently being investigated. We aimed to show the effectiveness of using a muscle flap as a recipient site for islet transplantation. Methods Islet cells were harvested from 12 isogenic Lewis rats, and then diabetes was induced in another 12 isogenic Lewis rats by streptozotocin injection. In six rats, 3,000 islets were transplanted into gastrocnemius muscle flaps, and in the other six rats, the same number of islets were transplanted into the gastrocnemius muscle. The transplanted islet cell function between the two groups was compared by means of blood glucose tests, glucose tolerance tests, immunohistochemistry, and real-time reverse transcription polymerase chain reaction. Results In the muscle flap group, blood glucose levels significantly decreased after islet transplantation. Blood glucose levels were significantly different between the two groups at 3 weeks after transplantation. The muscle flap group showed nearly normoglycemic results upon the glucose tolerance test, whereas the muscle group was hyperglycemic. Immunohistochemical evaluation showed positive results against insulin and glucagon in biopsies of both groups, and the islet cell density was higher in the muscle flap group. There were no statistically significant differences between the two groups in real-time reverse transcription polymerase chain reaction results. Conclusions Our results suggest that muscle flaps are promising candidates for islet cell transplantation.

Accounting Knowledge as a Contributing Intention on Improving Public Accounting Profession

  • ALIMBUDIONO, Ria Sandra
    • The Journal of Asian Finance, Economics and Business
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    • 제7권9호
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    • pp.801-809
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    • 2020
  • Public accountant profile dominated by over-50-year-old people appears to be alarming. The intention towards this profession had better be fostered immediately; therefore, the predictors to boost the intention need to be known. The study examines the influence of accounting knowledge toward the intention to work as public accountant using the Theory of Planned Behavior approach. A survey of 146 students revealed that there was a significantly positive influence of accounting knowledge toward the intention of becoming public accountant, both directly and indirectly, through the mediation of attitudes and perceived behavioral control. Subjective norms did not function as an appropriate mediation. The findings are expected to contribute to universities and professional accounting bodies. The study urges the accounting educators to redesign and reorganize the curriculum, including a more interesting teaching and learning methods. The professional accounting bodies are expected to cooperate with accounting educators in enhancing the internship program and providing real-case study to instill a positive attitude and assurance toward the students' competence, which, in the end, might spark the intention to work as public accountant. That accounting knowledge positively influences the intention toward public accounting profession through the mediation of perceived behavioral control was statistically supported.

Analysis of residential natural gas consumption distribution function in Korea - a mixture model

  • Kim, Ho-Young;Lim, Seul-Ye;Yoo, Seung-Hoon
    • 에너지공학
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    • 제23권3호
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    • pp.36-41
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    • 2014
  • The world's overall need for natural gas (NG) has been growing up fast, especially in the residential sector. The better the estimation of residential NG consumption (RNGC) distribution, the better decision-making for a residential NG policy such as pricing, demand estimation, management options and so on. Approximating the distribution of RNGC is complicated by zero observations in the sample. To deal with the zero observations by allowing a point mass at zero, a mixture model of RNGC distributions is proposed and applied. The RNGC distribution is specified as a mixture of two distributions, one with a point mass at zero and the other with full support on the positive half of the real line. The model is empirically verified for household RNGC survey data collected in Korea. The mixture model can easily capture the common bimodality feature of the RNGC distribution. In addition, when covariates were added to the model, it was found that the probability that a household has non-expenditure significantly varies with some variables. Finally, the goodness-of-fit test suggests that the data are well represented by the mixture model.

본드선도를 이용한 동적시스템의 해석적 종합방법 (An Analytical Synthesis Method of Dynamic Systems in Terms of Bond Graphs)

  • 박전수;김종식
    • 대한기계학회논문집A
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    • 제20권11호
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    • pp.3507-3515
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    • 1996
  • This paper presents an attempt to find the physical structure of dynamic systems which achieves the behavior of a given system function. The scheme pursued by the paper would be regarded as synthesizing dynamic systems, and a method to synthesize them analytically is proposed by means of bond graph prototypes. The method adopts several conceptsused to synthesize networks in the electrical field, but yet deconstrates its own strengths such as the freedom from assigning causality and determining junction types. Also, itis shown that this method has further advantages in reticulating a given specification into feedforward and feedback components relative to network synthesis and the method is examined though an example to trace the outline of the analytical synthesis of dynamic systems using bond graph prototypes.

직접속도 피드백을 이용한 지능판의 능동구조음향제어 (Active Structural Acoustical Control of a Smart Panel Using Direct Velocity Feedback)

  • Stephen J, Elliott;Paolo, Gardonio;Young-Sup, Lee
    • 한국소음진동공학회논문집
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    • 제14권10호
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    • pp.1007-1014
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    • 2004
  • This paper presents a study of low frequencies volume velocity vibration control of a smart panel in order to reduce sound transmission. A distributed piezoelectric quadratically shaped polyvinylidene fluoride (PVDF) polymer film is used as a uniform force actuator and an array of $4\;{\times}\;4$ accelerometer is used as a volume velocity sensor for the implementation of a single-input single-output control system. The theoretical and experimental study of sensor-.actuator frequency response function shows that this sensor-actuator arrangement provides a required strictly positive real frequency response function below about 900 Hz. Direct velocity feedback could therefore be implemented with a limited gain which gives reductions of about 15 dB in vibration level and about 8 dB in acoustic power level at the (1,1) mode of the smart panel. It has been also shown that the shaping error of PVDF actuator could limit the stability and performance of the control system.

균일힘 액추에이터와 가속도계 배열을 이용한 지능구조물의 능동구조 음향제어 (Active Structural Acoustical Control of a Smart Structure using Uniform Force Actuator and Array of Accelerometers)

  • 이영섭
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.368-373
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    • 2003
  • This paper presents a study of low frequencies volume velocity vibration control of a smart panel in order to reduce sound transmission. A distributed piezoelectric quadratically shaped polyvinylidene fluoride (PVDF) polymer film is used as a uniform force actuator and an array of 4$\times$4 accelerometer is used as a volume velocity sensor for the implementation of a single-input single-output con rot system. The theoretical and experimental study of sensor-actuator frequency response function sho vs that this sensor-actuator arrangement provides a required strictly positive real frequency response function below about 900Hz. Direct velocity feedback could therefore be implemented with a limited gain which gives reductions of about 15㏈ in vibration level and about 8 ㏈ in acoustic power level at the (1, 1) mode of the smart Panel. It has been also shown that the shaping error of PVDF actuator could limit he stability and performance of the control system.

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A Study on the Opt-in Marketing

  • OH, Won-Kyo;LEE, Won-Jun
    • 산경연구논집
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    • 제11권2호
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    • pp.49-59
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    • 2020
  • Purpose: Online and social media and mobile shopping are increasing and companies are required to provide personal information in order to supplement the non-invasive characteristics of the channels. With the increased provision of personal information, consumers' personal and social concerns about the prevention of personal information infringement are also increasing, and in response, personal or opt-in marketing has emerged to compensate for reckless information abuse. Despite the background of this emergence, the existing prior studies are limited to ignoring the negative feelings of consumers in the real world, including only the net function and positive effect of the opt-in mail. Research design, data and methodology: The research framework was intended to utilize the impact of human marketing activities on consumer attitudes combined with positive and negative factors. Factors that positively affect attitudes toward permation marketing were presented, such as informality, and perceived risks were presented as negative impact factors. Also, based on previous prior research, the prior factors of opt-in marketing were to present the effect on purchase intent through the medium of attitude toward opt-in marketing. Results: In this study, we used the framework of a two factor theory to address positive and negative factors as a leading factor in the customer attitude toward opt-in mail advertising, and as a result, functionality and personalization have a positive effect on customer attitude and perceived risk have a negative impact on customer attitude. In addition, it was confirmed that the customer attitude formed this way affects the intention to purchase again. Conclusions: This study suggests that we have demonstrated that marketing, an opt-in marketing that has been recognized as part of marketing that is deployed after obtaining customer consent, has been applied without any other marketing methodology. E-mail advertising at this point also provides practical implications that the system safeguards are in place under an opt-in protocol or system, and that even if an e-mail advertisement is carried out, customers will need to look at the level of awareness about the risks, and suggests that they need to consider the customer's journey that could lead to purchase at the content level.

퍼지신경망을 이용한 도로 씬의 차선정보의 잡음도 판별 (Fuzzy Neural Network-Based Noisiness Decision of Road Scene for Lane Detection)

  • 이운근;백광렬;권석근;이준웅
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 D
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    • pp.761-764
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    • 2000
  • This paper presents a Fuzzy Neural Network (FNN) system to decide whether or not the right information of lanes can be extracted from gray-level images of road scene. The decision of noisy level of input images has been required because much noises usually deteriorates the performance of feature detection based on image processing and lead to erroneous results. As input parameters to FNN, eight noisiness indexes are constructed from a cumulative distribution function (CDF) and proved the indexes being classifiers of images as the good and the bad corrupted by sources of noise by correlation analysis between input images and the indexes. Considering real-time processing and discrimination efficiency, the proposed FNN is structured by eight input parameters, three fuzzy variables and single output. We conduct much experiments and show that our system has comparable performance in terms of false-positive rates.

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Marangoni 대류계에서의 안정성 교환의 원리 (Principle of Exchange of Stabilities in the Marangoni Convection System)

  • 김민찬
    • Korean Chemical Engineering Research
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    • 제47권2호
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    • pp.262-265
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    • 2009
  • 초기에 안정하게 유지되고 있는 수평 유체층에서 급격한 온도 변화에 의한 Marangoni 대류 발생계에서 안정성 교환의 원리를 해석적으로 증명하였다. 선형 안정성 이론하에서 온도 및 속도의 교란량을 직교함수들의 선형 조합으로 나타내고, 온도 교란의 성장률이 모든 Marangoni 수 범위에 대하여 실수임을 보였다.

비례 방향제어 밸브에 의하여 구동되는 유압실린더-부하계의 단순 적응 위치제어 (Simple Adaptive Position Control of a Hydraulic Cylinder-load System Driven by a Proportional Directional Control Valve)

  • 조승호;이민우
    • 한국정밀공학회지
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    • 제28권8호
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    • pp.936-941
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    • 2011
  • This paper deals with the issue of motion control of a single rod cylinder-load system using simple adaptive control (SAC) method. Prior to controller design, the experiment of open-loop response has been performed. Based on it, design parameters of transfer function are obtained and used for controller design. The effect of parallel feedforward compensator has been investigated by computer simulation, suppressing the oscillatory motion. Through experiments it is conformed that the SAC method gives good tracking performance compared to the PD control method.