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      • 한계계단 응답특성을 이용한 영구자석형 동기전동기 속도제어

        박승엽,전인효,최중경 창원대학교 공작기계기술연구센터 1999 연구업적집 Vol.1 No.1

        본 논문에서는 한계계단 응답특성을 이용하여 영구자석형 동기전동기의 속도 제어계에 대한 새로운 자동 동조 PI(Proportional Integral)제어기를 설계하였다. 과도응답 기간동안 소위 한계입력이라고 하는 계단입력을 인가하여 PI 제어기의 자동동조를 위한 정보를 얻기 위한 기법을 제안한다. 시스템 파라메터 추정과 동시에 속도제어가 온라인으로 이루어지는데, 이것은 시스탬의 불확실성에도 불구하고 한계입력에 의해서 얻어진 시스템 파라메터 정보가 연속적으로 PI 제어기에 적용될 수 있다는 것이다. 제안된 자동동조 알고리즘은 단조증가 계단응답 특성을 갖는 영구 자석형 동기전동기의 속도제어에 대한 시뮬레이션과 실험결과를 통하여 그 유효함을 확인하였다. In this paper, a new auto-tuning PI controller for the speed servo system of a PMSM is designed by using limited step response characteristics. The method is proposed that gets information about auto-tuning of PI regulator by the injection fo step input, called limited input, during a transient response time of control. System parameter estimation and speed control could be continuously executed. This means that in despite of system uncertainty the system information obtained by limited input can be continuously applied to the PI regulator. We demonstrate the effectiveness of the proposed auto-tuning algorithm through simulation and experiment result of the speed control for a PMSM having monotone increasing step response.

      • 시변 이득을 갖는 가변구조 제어 이론을 적용한 브러시리스 전동기의 속도 제어계

        박승엽,김종선,최중경 國立 昌原大學校 産業技術硏究所 1995 産技硏論文集 Vol.9 No.-

        A variable structure controller is designed to control the speed of trapezoidal type BLDC servo motor which could achieve simple control circuit structure in driving system. This control system is implemented by using DSP(Digital Signal Processor TMS320C25) and full digitalized circuit. A modified variable structure control algorithm is adopted for the fast response characteristics and more power efficiency.

      • 펜타곤 결선방식의 5상 스테핑 모터에 대한 미세각 구동 드라이버의 설계

        박승엽,김형우,최중경 國立 昌原大學校 産業技術硏究所 1997 産技硏論文集 Vol.11 No.-

        This paper is about design of micro-stepping driver for 5-phase stepping motor having pentagon type winding. For realization of micro-stepping for 5-phase stepping motor, the current of each phase have sinusoidal type with 72˚delay. In the case of pentagon type winding stepping motor with excellent damping peculiarity, this phase current form earns from control of in-let current to 5 power line. Proposed method uses two techniques for the control of phase current. These are PWM method and analog current amplifying method. Especially, by applying analog current amplifying method fine control of phase current obtained. Therefore, we could reduce the stepping motor's vibration at low speeds due to rotor inertia and the settling-time at the moment when the rotor stops.

      • 의무고용제도 재설계 방안

        김종진,장창엽,유완식,김언아,이정주,류정진,강필수,최종철,남용현,김윤삼 한국장애인고용촉진공단 고용개발원 2008 연구개발 Vol.- No.2

        현행 우리나라 의무고용제도는 장애인구의 급격한 증가, 장애인차별금지 및 권리구제 등에 관한 법률의 도입 등 외부환경변화에 신축적으로 대처하지 못하고, 경증장애인 중심으로 의무고용제도가 운영됨으로써 중증장애인의 고용배제가 우려되고 있다. 본 보고서는 이러한 문제점을 해결하기 위해 의무고용제도의 일자리 확대와 고용증가를 통해 중증장애인의 고용기회를 확대할 수 있는 정책방안을 제시하기 위한 것이다. 본 보고서는 (1)의무고용 사업체의 의무고용 산정인원에서 자립장애인 제외 (2)현행 2% 의무고용률을 3%로 상향 조정 (3)사업체가 고용하는 중증장애인에 대한 더블카운트(2배) 가산제도 도입 (4)의무고용률 미달 사업주에 대한 부담금 차등징수의 4가지 정책방안, 제도 합리화 차원에서 장려금 지급방식의 개선과 사업주의 장애인에 대한 인식개선 방안을 제시하였다. 정책방안에 대한 영향분석 결과 의무고용 적용대상자에서 비장애인과 고용상 차별되지 않는 자립장애인(6등급)을 의무고용 산정인원에서 제외하는 경우 의무고용 사업체의 고용인원은 23,296명이 감소해 고용률은 1.35%에서 0.88%로 감소하였고, 의무고용 사업체의 장애인 일자리 수는 미고용인원의 증가로 15,152개가 증가하였다. 그리고 기금은 부담금이 631억원 증가하고, 장려금이 352억원 감소해 983억원의 수지개선 효과가 발생하는 것으로 나타났다. 의무고용 사업주의 의무고용률 3% 인상 방안은 의무고용률 상향 조정에 따른 미고용인원의 증가로 장애인의 일자리 수는 43,101개가 증가하고, 기금은 부담금이 1,709억원 증가하는 반면, 장려금은 293억원이 감소해 2,002억원의 수지개선 효과가 발생하는 것으로 나타났다. 의무고용 사업주가 고용하는 중증장애인을 2인으로 더블카운트 하는 중증장애인 가산제도의 도입은 의무고용 사업체의 장애인근로자가 67,261명에서 79,685명(1,2등급만 포함시 75,685명)으로 증가하여 고용률은 1.35%에서 1.60%(1.2등급만 포함시 1.52%)로 증가하고, 의무고용률 미달 사업체의 미고용 인원이 감소하여 2,745개의 일자리가 감소하였다. 그리고 기금은 부담금이 118억원 감소하는 반면, 장려금은 418억원이 증가해 536억원의 수지악화가 발생하는 것으로 나타났다. 의무고용률 미달 사업체의 고용유인을 위해 고용률 1.0%미만, 1.0-1.5%, 1.6-2.0% 미만에 대해 각각 20%, 10%, 5%의 할증률을 순차적으로 가중하여 부과하는 부담금 차등징수 방안(3차년까지의 효과임)은 1.0% 미만 사업주는 86만원, 1.0-1.5% 사업주는 64만원, 1.6-2.0% 미만 사업주는 58만원의 부담기초액을 부과할 때 고용률은 1.35%에서 1.53%로 증가(1.6-2.0% 미만 사업주는 의무고용률 2%를 달성)하고, 미고용인원의 감소로 장애인의 일자리는 8,836개가 감소하는 것으로 나타났다. 그리고 기금은 부담금이 58억원 감소하여 수지는 악화되었다. 이상의 네 가지 방안은 모두 장애인의 고용증대를 가져온다는 측면에서는 유효하지만, 장애인의 일자리 확대를 통한 중증장애인의 고용을 증대한다는 정책목표를 달성하는 데에는 한계점을 안고 있기 때문에 어느 한 정책만을 선택하기보다는 정책효과를 극대화하기 위해 정책결합(policy mix)을 이용하는 것이 바람직함을 제시해주었다. 즉, 의무고용 적용대상자 조정방안/의무고용률 상향조정 방안과 중증장애인 가산제도/부담금 차등징수 방안을 조합 또는 모두 동시에 선택하는 경우 의무고용 사업체의 장애인 일자리 수의 확대와 중증장애인 고용을 동시에 달성하고, 기금의 수지균형도 달성 가능한 것으로 나타났다. The mandatory employment quota system of Korea does not reflect the changing external factors such as the growing population of people with disabilities(PWDs) and the enactment of the Anti-discrimination Law for People with Disabilities. The current employment quota system focuses on people with mild disabilities thus excluding people with severe disabilities from employment. The purpose of this report is to propose a plan in order to increase employment opportunity for the severely disabled through the reform of the employment quota system. This report analyzes the following : (1) exclude grade 6 disability from mandatory employment quota (2) raise the employment quota from 2% to 3% (3) implement the double counting for employers that employ the severely disabled (4) differentiate the amount of levy collected from corporations that are unable to meet the quota. The aforementioned plans are useful in that they increase employment for people with disabilities. However, there are limitation to reaching the policy objectives by increasing jobs for people with severe disabilities. Therefore, to maximize the effects we should consider policy mix of these four policies. In other words, by mixing the policies of adjusting the employment quota target/raising the quota ratio and implementing the double count/differentiating the amount of levy, we can achieve the goal of increasing jobs for the severely disabled and maintain equilibrium between incomings and outcomings.

      • 온라인 동조 PI 제어기법을 이용한 영구자석형 동기전동기의 속도제어기 설계

        林相德,朴勝燁,全寅孝,崔重暻 창원대학교 공작기계기술연구센터 1999 연구업적집 Vol.1 No.1

        본 논문은 브러시리스 직류 전동기의 속도제어를 위해 파라메타의 추정 없이 입력과 출력의 패턴을 관찰하여 PI 이득을 온라인(On-line)으로 설정하는 방법을 제안한다. 비례이득은 한계입력을 인가하여 가장 빠른 속도 상승을 유도하는 과정에서 설정되고, 적분이득은 비례제어 과정 중에 오버슈트 방지와 안정된 수렴이 적적히 이루어지도록 설정된다. 따라서 제안된 PI이득 조정은 온라인으로 제어와 동시에 수행됨으로써 시스템 파라메타 추정 등의 부가적인 작업이 필요 없다. 본 논문에서 제안하는 PI이득 조절기법은 직류전동기의 속도제어에 있어서 빠른 응답과 오버슈트 문제를 동시에 해결할 수 있고, 기존의 Auto-tuning 방법보다 간편하고 실용적이다. 컴퓨터 시뮬레이션과 실제 실험을 통하여 제안하는 방법의 유용성과 안정성을 보인다. In this paper, a method of on-line PI gain-tuning is proposed for the speed control of brushless D.C. motor by investigating the pattern of input and output without estimating parameter. Proportional gain is tuned in the process to obtain a fast speed response by supplying the maximum constant input And integral gain is appropriately tuned in the process of proportional control so that the response may be stably converged and the overshoot may be prevented. Therefore because both control and gain-tuning are executed concurrently, additional works that estimate parameters and so on aren't required in the proposed method. In the proposed method, both fast-response and overshoot problem are well solved, and it is mire useful and convenient than existing auto-tuning methods in the speed control of D.C motor. It is illustrated by simulations and experimental results that the proposed method is useful and stable.

      • SCIESCOPUSKCI등재

        The expression of a nitric oxide derivative, tissue inhibitors of metalloproteinase-3, and tissue inhibitors of metalloproteinase-4 in chronic periodontitis with type 2 diabetes mellitus

        Jung, Hyun-Yub,Kim, Yong-Gun,Park, Jin-Woo,Suh, Jo-Young,Lee, Jae-Mok Korean Academy of Periodontology 2013 Journal of Periodontal & Implant Science Vol.43 No.2

        Purpose: The purpose of this study was to analyze the expression of inducible nitric oxide synthases (iNOS), tissue inhibitors of metalloproteinase $(TIMP)_{-3}$, and $TIMP_{-4}$ in the gingival tissues of periodontal patients with or without type 2 diabetes mellitus (DM). Methods: Depending on the patient's systemic condition and clinical criteria of the gingiva, each gingival sample was classified into one of three groups. Sixteen clinically, systemically healthy patients (group 1), 16 periodontal patients (group 2), and 16 periodontal patients with DM (group 3) were included. Tissue samples in each group were collected, prepared, and analyzed by western blotting. Quantification of the relative amount of $TIMP_{-3}$, $TIMP_{-4}$, and iNOS was performed. Results: The expression levels of iNOS and $TIMP_{-3}$ both increased in group 1, group 2, and group 3 in increasing order, and were significantly higher in both group 2 and group 3 as compared to group 1 (P<0.05). The expression levels of $TIMP_{-4}$ increased in the same order, but significantly increased in group 2 as compared to group 1, in group 3 as compared to group 1, and group 3 as compared to group 2 (P<0.05). Conclusions: This study demonstrated that iNOS, $TIMP_{-3}$, and $TIMP_{-4}$ might be involved in the progression of periodontal inflammation associated with type 2 DM. It is thought that further study of these factors can be applied practically for the diagnosis and control of periodontitis in diabetics.

      • Image Segmentation by Edge Partitioning over a Nonsubmodular Markov Random Field

        Jung, Ho Yub,Lee, Kyoung Mu Hindawi Limited 2015 Mathematical problems in engineering Vol.2015 No.-

        <P>Edge weight-based segmentation methods, such as normalized cut or minimum cut, require a partition number specification for their energy formulation. The number of partitions plays an important role in the segmentation overall quality. However, finding a suitable partition number is a nontrivial problem, and the numbers are ordinarily manually assigned. This is an aspect of the general partition problem, where finding the partition number is an important and difficult issue. In this paper, the edge weights instead of the pixels are partitioned to segment the images. By partitioning the edge weights into two disjoints sets, that is, cut and connect, an image can be partitioned into all possible disjointed segments. The proposed energy function is independent of the number of segments. The energy is minimized by iterating the QPBO-α-expansion algorithm over the pairwise Markov random field and the mean estimation of the cut and connected edges. Experiments using the Berkeley database show that the proposed segmentation method can obtain equivalently accurate segmentation results without designating the segmentation numbers.</P>

      • Bortezomib Facilitates Reparative Dentin Formation after Pulp Access Cavity Preparation in Mouse Molar

        Jung, Jae-Kwang,Gwon, Gi-Jeong,Neupane, Sanjiv,Sohn, Wern-Joo,Kim, Ki-Rim,Kim, Ji-Youn,An, Seo-Young,Kwon, Tae-Yub,An, Chang-Hyeon,Lee, Youngkyun,Kim, Jae-Young,Ha, Jung-Hong Elsevier 2017 JOURNAL OF ENDODONTICS - Vol.43 No.12

        <P><B>Abstract</B></P> <P><B>Introduction</B></P> <P>The aim of this study was to evaluate <I>in vitro</I> and <I>ex vivo</I> roles of bortezomib, a proteasome inhibitor that binds to the active site of the 26S proteasome, in tertiary dentin formation.</P> <P><B>Methods</B></P> <P>We established pulpal access cavity preparation that was treated with or without bortezomib before direct pulp capping with a calcium hydroxide–based material. We also analyzed bone morphogenetic protein (Bmp)- and Wnt-related signaling molecules using quantitative real-time polymerase chain reaction.</P> <P><B>Results</B></P> <P>In the short-term observation period, the bortezomib-treated pulp specimens showed the period-altered immunolocalization patterns of nestin, CD31, and myeloperoxidase, whereas the control specimens did not. The bortezomib-treated group showed a complete dentin bridge with very few irregular tubules after 42 days. The micro–computed tomographic images showed more apparent dentin bridge structures in the treated specimens than were in the controls. Quantitative real-time polymerase chain reaction analysis showed up-regulated Bmp and Wnt.</P> <P><B>Conclusions</B></P> <P>These findings revealed that treatment with 1 μmol/L bortezomib induced reparative dentin formation that facilitated the maintenance of the integrity of the remaining pulpal tissue via early vascularization and regulation of Bmp and Wnt signaling.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bortezomib facilitates reparative dentin formation through modulated vascularization and inflammatory response. </LI> <LI> Molecular mechanisms underlying bortezomib treatment would be related with Bmp and Wnt signaling. </LI> <LI> Pulpal access cavity preparation using a mice model system permits us to evaluate a range of drugs for their ability of reparative dentin formation. </LI> </UL> </P>

      • KCI등재

        Development of an experimental model for radiation-induced inhibition of cranial bone regeneration

        Jung, Hong-Moon,Lee, Jeong-Eun,Lee, Seoung-Jun,Lee, Jung-Tae,Kwon, Tae-Yub,Kwon, Tae-Geon Korean Association of Maxillofacial Plastic and Re 2018 Maxillofacial Plastic Reconstructive Surgery Vol.40 No.-

        Background: Radiation therapy is widely employed in the treatment of head and neck cancer. Adverse effects of therapeutic irradiation include delayed bone healing after dental extraction or impaired bone regeneration at the irradiated bony defect. Development of a reliable experimental model may be beneficial to study tissue regeneration in the irradiated field. The current study aimed to develop a relevant animal model of post-radiation cranial bone defect. Methods: A lead shielding block was designed for selective external irradiation of the mouse calvaria. Critical-size calvarial defect was created 2 weeks after the irradiation. The defect was filled with a collagen scaffold, with or without incorporation of bone morphogenetic protein 2 (BMP-2) (1 ㎍/ml). The non-irradiated mice treated with or without BMP-2-included scaffold served as control. Four weeks after the surgery, the specimens were harvested and the degree of bone formation was evaluated by histological and radiographical examinations. Results: BMP-2-treated scaffold yielded significant bone regeneration in the mice calvarial defects. However, a single fraction of external irradiation was observed to eliminate the bone regeneration capacity of the BMP-2-incorporated scaffold without influencing the survival of the animals. Conclusion: The current study established an efficient model for post-radiation cranial bone regeneration and can be applied for evaluating the robust bone formation system using various chemokines or agents in unfavorable, demanding radiation-related bone defect models.

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