• Journal of Power Electronics
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• 제18권2호
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• pp.432-444
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• 2018

This paper presents a capacitor voltage balancing topology using a three-level boost converter (TLBC) for a neutral point clamped (NPC) three-level inverter fed surface permanent magnet synchronous motor drive (SPMSM). It enhanced the performance of the drive in terms of its voltage THD and torque pulsation. The main attracting feature of the proposed control is the boosting of the input voltage and at the same time the balancing of the capacitor voltages. This control also reduces the computational complexity. For the purpose of close loop vector control, a software based cost effective resolver to digital converter RDC-less estimation is implemented to calculate the speed and position. The proposed drive is simulated in the MATLAB/SIMULINK environment and an experimental investigation using dSPACE DS1104 validates the proposed drive system at different operating condition.

• Journal of Oral Medicine and Pain
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• 제30권3호
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• pp.353-360
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• 2005

측두하악장애 연구진단기준 (Research Diagnostic Criteria for Temporomandibular Disorders; RDC/TMD)을 이용하여 측두하악장애 환자들에서 심리학적 상태 및 턱기능장애의 정도가 통증의 정도 및 지속기간, 통증과 관련된 일상생활 장애의 정도 및 기간, 만성통증척도에 미치는 영향 등을 알아보기 위하여 RDC/TMD axis I criteria에 따라 측두하악장애로 진단받은 평균연령 30.1$\pm$12.5 세인 93 명의 환자들(남성 17명, 여성 76명)을 대상으로 RDC/TMD axis II 병력 설문지를 작성하게 한 뒤, 우울증점수, 신체화장애점수, 턱기능장애점수와 만성통증척도의 통증 강도, 통증 지속기간, 통증과 연관된 장애 점수, 통증과 연관된 장애의 기간 및 만성통증척도 사이의 연관성을 분석하여 다음과 같은 결론을 얻었다. 1. 93명의 측두하악장애 환자들에서 만성통증척도의 경도의 장애를 보이는 군 (low disability group, grade I and II)은 42.0% 이었으며, 심도의 장애를 보이는 군 (high disability group, grade III and IV)은 51.5% 이었다. 2. 우울증점수는 통증 강도, 통증 지속기간, 통증과 연관된 장애 점수, 통증과 연관된 장애의 기간, 만성통증척도 모두에 통계적으로 유의한 영향을 미치지 않았다. 3. 신체화장애점수는 통증 강도 (p<0.01), 통증과 연관된 장애의 기간 (p<0.01), 만성통증척도 (p<0.01)에 유의한 영향을 미쳤으나, 통증 지속기간이나 통증과 연관된 장애 점수에는 통계적으로 유의한 영향을 미치지 않았다. 4. 턱기능장애점수는 통증 강도 (p<0.001), 통증과 연관된 장애의 기간 (p<0.01), 만성통증척도 (p<0.001)에 유의한 영향을 미쳤으나, 통증 지속기간이나 통증과 연관된 장애 점수에는 통계적으로 유의한 영향을 미치지 않았다. 측두하악장애환자에서 신체화장애와 턱기능장애는 환자가 느끼는 통증의 강도 및 장애의 정도와 밀접하게 관련되어 나타날 수 있으며, 환자가 호소하는 정서적 스트레스에 대한 포괄적인 이해와 기능장애에 대한 적절한 관리가 측두하악장애 환자의 성공적인 치료에 매우 중요하리라 생각된다.

• Journal of Electrical Engineering and Technology
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• 제8권6호
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• pp.1310-1319
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• 2013

Resolvers are transducers that are used to sense the angular position of rotational machines. The analog resolver is necessary to use resolver to digital converter. Among the RDC software method, angle tracking observer (ATO) is the most popular method. In an actual resolver-based position sensing system, amplitude imbalance dominantly distorts the estimate position information of ATO. Minority papers have reported position error compensation of resolver's output signal with amplitude imbalance. This paper proposes new ATO algorithm in order to compensate position errors caused by the amplitude imbalance. There is no need premeasured off line data. This is easy, simple, cost-effective, and able to work on line compensation. To verify feasibility of the proposed algorithm, simulation and experiments are carried out.

• 대한안전경영과학회지
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• 제3권3호
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• pp.77-86
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• 2001

An operational strategy for inventory control on finished goods in the distribution system has been given attention to many enterprises and many studies regarding this field have been done and is also on-going currently. Many of these studies represented a large scale distribution network with a unified formulation by using defined symbols. These methods have provided the systematic approach of the distribution network but they are impossible to applying the reality system due to not considering the service rate of demand and treating the shortage of inventory. In order to overcome these unrealistic problems, the novel safety stock policy of responding to customers' inventory distribution network is suggested. this paper explores the transportation between Central Distribution Center(CDC) and Regional Distribution Center(RDC). Especially, the relation of transportation cost between CDC and RDC and cost of inventory control according to safety inventory with service level are emphasized. We could obtain the good results of this study by determining the optimal safety stock considering the various variables and constraints.

• 정보처리학회논문지B
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• 제8B권4호
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• pp.419-428
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• 2001

ITU(International Telecommunication Union)를 비롯한 IMTC 등의 국제 표준기구에서는 멀티미디어 회의서비스를 제공하기 위하여 필요한 여러 가지 응용들과 프로토콜 등에 대하여 ITU-T T.120 시리즈로 표준화 작업을 진행하고 있다[1-10]. 그 중 원격 기기 제어는 멀티미디어 회의에 다음의 능력을 제공한다. 첫째, 회의 참가자가 회의 내 기기 및 기기가 제공하는 속성들을 파악할 수 있게 해준다. 둘째, 회의 참가자가 기기를 배타적 및 비 배타적으로 제어할 수 있게 해준다. 셋째, 회의 참가자가 기기의 상태를 파악하고, 사건통지를 받을 수 있게 해준다. 넷째, 회의 참가자가 외부 기기를 선택하여 그 정보를 받을 수 있게 해준다. 본 논문에서는 멀티미디어 회의에서 원격 기기 제어를 수행하기 위하여 사용되는 RDC(Remote Device Control) 및 구현된 시스템을 소개한다. RDC 프로토콜은 현재 T.136[1]으로 표준화되고 있으며 T.120 모델에서 응용 프로그램 실체[2]로 등록하여 운용되고 있다. 소개되는 시스템은 T.136을 근거로 하여 구현되었으며, 다수의 기능을 추가하여 그 기능을 개선하였다.

• Macromolecular Research
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• 제15권3호
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• pp.225-233
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• 2007

To improve the poor mechanical and low-temperature properties of glycidyl azide polymer (GAP)-based propellants, the addition of binders was investigated using GAP and flexible polymer backbone-structural polycaprolactone (PCP) at various weight(wt) ratios, and varying the ratio of Desmodur N-100 pluriisocyanate (N-100) to isophorone diisocyanate (IPDI). Using Gee's theory, the solubility parameter of the PCP network was determined, in order to elucidate the physical and chemical interaction between GAP and PCP. The structure of the binder networks was characterized by measuring the cross-link densities and molecular weights between cross-links ($M_c$) obtained by a swelling experiment using Flory-Rhener theory. The thermal and mechanical properties of the segmented block copolyurethane (GAP-b-PCP) binders prepared by the incorporation of PCP into the binder recipes were investigated, along with the effect of the different curatives ratios.

• International Journal of Internet, Broadcasting and Communication
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• 제15권1호
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• pp.1-7
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• 2023

TCP is considered a major candidate transport protocol even for constrained IoT networks due to its ability to integrate into the existing network infrastructures. Since TCP implementations such as uIP TCP often allow only a single TCP segment per connection to be unacknowledged at any given time due to resource constraints, the congestion control relies only on RTO management. In our previous work, to address the problem that uIP TCP performs poorly particularly when a radio duty cycling mechanism is enabled and the hidden terminal problem is severe, we proposed a RTO scheme for uIP TCP and validated the performance through Cooja simulation. In this study, we investigate the effect of other factors that were not considered in our previous work. More specifically, the effect of traffic intensity, the degree of the hidden terminal problem, and RDC is investigated by varying the offered load and the transmission range, and the RDC channel check rate. Simulation results imply that we need to further investigate how to improve TCP performance when the radio duty cycling mechanism is used.

• 한방안이비인후피부과학회지
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• 제35권1호
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• pp.63-68
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• 2022

Objectives : To get to know the effects of placental extract and laser theraphy for Temporomandibular Joint Disorder, we have tried a injection of placental extract and laser theraphy into 聽宮(SI19), 聽會(GB02) for patient with Temporomandibular Joint Disorder. Methods : In this case clinical assessment of temporomandibular joint dysfunction is assessed by the VAS score and the Korean Version of Research Diagnostic Criteria for Temporomandibular Disorders(RDC/TMD). Results : The VAS score was significantly decreased after Placental extract herbal acupuncture and laser theraphy Conclusion : Placental extract herbal acupuncture and laser theraphy effectively resolved pain for Temporomandibular Disorders.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
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• pp.209-209
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• 2003

• 약학회지
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• 제37권4호
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• pp.370-382
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• 1993

In order for formulation of rectal containing OMZ, the OMZ suppositories were prepared using water-soluble base, PEG 4000 base and oil-soluble base, Witepsol H 15. Chemical stability of OMZ in suppositories was increased when Witepsol H 15 was used as a suppository base and arginine was added as a stabilizer. The decomposition of OMZ in suppository bases followed the first-order kinetics and their rate constants were 0.11 day $^{1}(t_{1/2}$=/6.25 days) for Witepsol H 15 suppository and 0.48 day $^{1}(t_{1/2}$=/1.43 days) for PEG 4000 suppository, respectively. On the other hand, the decomposition rate constants of Witepsol suppository and PEG suppository stabilized with arginine were 3.89$\times$10$^{-3}$(t$_{1/2}$=171.1 days) and 8.76$\times$10$^{-3}$ day $^{1}(t_{1/2}=79.9 days), respectively. Shelf-lives of the Witepsol and PEG suppositories stabilized with arginine were t$_{90%}$=291.8 days and t$_{90%}$=282.1 days at $35^{\circ}C$ and 75% RH, respectively. The dissolution test of OMZ suppositories was performed by rotating dialysis cell(RDC) method and the release rate constant was calculated by the simplified Higuchi's equation, Q'=K' t$^{1/2}$. Dissolution of OMZ from suppositories was augmented as arginine was added, particle size of OMZ was reduced and a suitable surfactant such as SLS was added. RDC method was more appropriate and available than Paddle method to evaluate the dissolution rate of lipophilic-base suppositoies. Arginine was found to be a very useful exipient for the enhancement of stability and dissolution of OMZ in suppositories.