• 한국산학기술학회논문지
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• 제16권11호
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• pp.7934-7940
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• 2015

도시철도의 표정속도를 증가시키기 위한 여러 가지 방법 중 가속도를 높이는 방법이 있다. 전동기의 견인력을 높이면 일정 목표 수준까지는 가속도를 향상시킬 수 있으나 점착력 제한 등으로 어느 수준 이상에서는 슬립이 발생하여 목표 가속도를 낼 수 없게 된다. 주행저항도 목표 가속도 선정 시 고려해야 할 요소이다. 견인력과 점착력 및 주행저항은 속도에 따라 변하는 함수이므로 가속도 규격을 선정하기 위해서는 속도에 따른 견인력, 점착력, 주행저항 등의 변화에 대한 분석이 필요하다. 본 연구에서는 차세대전동차를 대상으로 하였는데 이 전동차의 경우 전두부가 유선형이고 1C1M 방식의 모터제어를 수행하므로 기존의 주행저항 수식과 점착력 수식을 적용하는 것은 적합하지 않다. 따라서, 본 연구에서는 견인력과 점착력 수식으로부터 가속도 제한을 구하고 실제 시험 결과와 비교하여 대상 전동차에 맞는 점착력 수식을 도출한다. 이를 바탕으로 차세대전동차의 M카, T카 편성을 변경할 경우 수치적으로 가능한 최대 가속도 규격을 도출한다. 이렇게 이론적 한계를 제시함으로써 실제 가속도 규격 선정 시 도움이 될 수 있도록 한다.

• 정보처리학회논문지D
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• 제11D권6호
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• pp.1259-1268
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• 2004

제한된 훈련장안에서 실전에 대비한 훈련이 되려면, 다양한 전투상황이 부여된 현실감 있는 모의훈련이 필수적이다. 본 논문에서는 현실감 있는 모의훈련을 위해 가상영상이 아닌 지상기반 CCD 카메라영상에 지정된 시나리오대로 가상표적을 전시하는 방법을 제안한다. 이를 위해 고해상도 GeoTIFF(Geographic Tag Image File Format) 위성 영상과 DTED(Digital Terrain Elevation Data)를 이용하여 현실감 있는 3차원 모델을 생성(운용자용)하고, 입력된 CCD 영상(운용자, 훈련자용)으로부터 도로를 추출하였다. 위성영상과 지상기반 센서영상은 관측위치, 분해능, 스케일 등에 많은 차이가 있어 특징기반 정합이 어렵다. 따라서 본 논문에서는 영상 워핑함수인 TPS(Thin-Plate Spline) 보간 함수를 일치하는 두개의 제어점 집합에 적용하여 3차원 모델에 표시된 이동경로를 따라 CCD 영상에서도 표적이 전시되는 이동 동기화 방법을 제안하였다. 실험환경은 Pentium4 1.8MHz(RAM 512M)의 PC 2대를 사용하였으며, 실험 영상은 대전지역의 위성영상과 CCD 영상을 이용, 제안한 알고리즘의 유효성을 입증하였다.

• 한국지역지리학회지
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• 제18권3호
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• pp.336-350
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• 2012

본 연구는 보존가치가 있는 금오도 지역의 지형 지질 경관자원에 관한 전문적인 지식을 기반으로 생태 역사 문화적 요소를 포함하여 금오도의 지역성을 경험할 수 있도록 지오싸이트(geosite)를 발굴하고 해설하는 데 초점을 맞추었다. 지형 지질 경관자원으로서 서부 해안에 위치한 '미역널방' 신선대의 해식애, 직포 사빈, '갈바람통'의 해식애와 해식동, 충산의 육계사주와 육계도, 장지 암설 역빈과 동부 해안에 위치한 여천 대유의 응회암, 연목 '검바위' 우학리의 안산암 분포지를 지오싸이트로 선정하였다. 전반적으로 중생대 퇴적층과 화산암으로 이뤄진 지형들이 발달하였다. 탐방경로는 금오도의 북서쪽 함구미 선착장에서 남동쪽 장지 마을로 이어지는 '비렁길'루트와 동부해안도로를 따라 구성하였으며, 암설지대가 나타나는 장지를 사례로 관광해설표지판을 예시해 보았다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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• pp.186-186
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• 2000

After LeComber et al. reported the first amorphous hydrogenated silicon (a-Si: H) TFT, many laboratories started the development of an active matrix LCDs using a-Si:H TFTs formed on glass substrate. With increasing the display area and pixel density of TFT-LCD, however, high mobility TFTs are required for pixel driver of TF-LCD in order to shorten the charging time of the pixel electrodes. The most important of these drawbacks is a-Si's electron mobiliy, which is the speed at which electrons can move through each transistor. The problem of low carier mobility for the a-Si:H TFTs can be overcome by introducing polycrystalline silicon (poly-Si) thin film instead of a-Si:H as a semiconductor layer of TFTs. Therefore, poly-Si has gained increasing interest and has been investigated by many researchers. Recnetly, fabrication of such poly-Si TFT-LCD panels with VGA pixel size and monolithic drivers has been reported, . Especially, fabricating poly-Si TFTs at a temperature mach lower than the strain point of glass is needed in order to have high mobility TFTs on large-size glass substrate, and the monolithic drivers will reduce the cost of TFT-LCDs. The conventional methods to fabricate poly-Si films are low pressure chemical vapor deposition (LPCVD0 as well as solid phase crystallization (SPC), pulsed rapid thermal annealing(PRTA), and eximer laser annealing (ELA). However, these methods have some disadvantages such as high deposition temperature over $600^{\circ}C$, small grain size (<50nm), poor crystallinity, and high grain boundary states. Therefore the low temperature and large area processes using a cheap glass substrate are impossible because of high temperature process. In this study, therefore, we have deposited poly-Si thin films on si(100) and glass substrates at growth temperature of below 40$0^{\circ}C$ using newly developed high rate magnetron sputtering method. To improve the sputtering yield and the growth rate, a high power (10~30 W/cm2) sputtering source with unbalanced magnetron and Si ion extraction grid was designed and constructed based on the results of computer simulation. The maximum deposition rate could be reached to be 0.35$\mu$m/min due to a high ion bombardment. This is 5 times higher than that of conventional sputtering method, and the sputtering yield was also increased up to 80%. The best film was obtained on Si(100) using Si ion extraction grid under 9.0$\times$10-3Torr of working pressure and 11 W/cm2 of the target power density. The electron mobility of the poly-si film grown on Si(100) at 40$0^{\circ}C$ with ion extraction grid shows 96 cm2/V sec. During sputtering, moreover, the characteristics of si source were also analyzed with in situ Langmuir probe method and optical emission spectroscopy.

• Korean Journal of Acupuncture
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• 제29권1호
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• pp.83-92
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• 2012

Objectives : The purpose of this research was to develop the magnetic acupuncture system which used solenoid coil for magnetizing acupuncture needle. The system could generate the meridian electric potential (MEP) similar to the potential by manual acupuncture. Thus, we tried to confirm the therapeutic effect that is caused by the MEP generation. Methods : To confirm the MEP, we stimulated the magnetic acupuncture with at 2Hz, $92.7{\pm}2mT$, PEMFs (Pulsed Electro-Magnetic Fields) at ST37 and measured the evoked potential between ST36 and ST41. Also, we conducted a fatigue recovery test using isokinetic exercise in order to identify the therapeutic effect on musculoskeletal disorders. We chose LR9 as a stimulation point. To observe the state of fatigue, we measured the EMG and analyzed median frequency and peak torque for 20minutes. Results : We observed that MEP which incurred from magnetic acupuncture was higher than he reported MEP induced by manual acupuncture. Moreover, its modes were divided into two types by the direction of magnetic flux. When generating magnetic flux in the direction of acupoint, the positive peak voltage of the MEP was generated. In contrast, negative peak voltage of the MEP was generated whenever meganetic flux generated in the outward direction. As a result of fatigue recovery, the median frequency (MF) of the magnetic acupuncture group were recovered faster than that of the non-stimulation group. However, the peak torques of both groups were not restored until after 20 minutes. Conclusions : We confirmed that the magnetic acupuncture system can lead to the MEP similar to manual acupuncture. Moreover, the MEP had a therapeutic effect on the musculoskeletal disorders.

• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.366-378
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• 1998

Thermocondensation root canal filling technique have been used to fill accessary canals or to obtain homogeneous root caral fillings. But these thermocondensation technique inevitably produce heat in the canal which can be transmitted through the dentin and cementum and consequently damage periodontal ligamental cells and osteoblasts. In this study, System $B^{TM}$(Analytic technology, WA.D.S.A.) was used to evaluate the reaction of periodontal ligament tissue to "Continous Wave condensation technique" introduced by Buchanan, and the transmitted root surface temperature was measured according to measured root thicknesses. 12 Mandibular incisors of two adult dogs were used for the experiment. 6 controls were filled by lateral condensation technique with sealer.3 specimens were apically filled by Continuous Wave technique at $200^{\circ}C$ for 5 seconds and remaining 3 specimens were additionally backfilled using System $B^{TM}$(Analytic technology, WA.D.S.A.) was used to evaluate the reaction of periodontal ligament tissue to "Continous Wave condensation technique" introduced by Buchanan, and the transmitted root surface temperature was measured according to measured root thicknesses. 12 Mandibular incisors of two adult dogs were used for the experiment. 6 controls were filled by lateral condensation technique with sealer.3 specimens were apically filled by Continuous Wave technique at $200^{\circ}C$ for 5 seconds and remaining 3 specimens were additionally backfilled using System $B^{TM}$ at $100^{\circ}C$ for 20 seconds. Six weeks later, the dogs were sacrificed and the teeth stained with Hematoxylin and Eosin for histologic examination. 6 extracted human teeth were used to measure the transmitted temperature. After cutting off the crown, the canals were prepared and divided into 3 groups with root thickness of 1.5mm, 1.0mm, 0.5mm, 2 teeth in each group. Inside each root canal, System $B^{TM}$ was heated as with the temperature for the apically condensed and the back filled group, and the transmitted heat was measured on the external surface of the root. The temperature of System $B^{TM}$ heat spreader at $200^{\circ}C$ and $100^{\circ}C$ was also measured at root temperature. It can be concluded as follows: 1. In the thin area (200-$250{\mu}m$) of the root, root resorption could be seen even with heating at $200^{\circ}C$ for 5 seconds. 2. When the spreader was heated at $200^{\circ}C$ for 5 seconds and additionally at $100^{\circ}C$ for 20 seconds for backfill, all teeth showed root resorption regardless of their root thickness. 3. The transmitted external root surface temperature was higher as the root thickness decreased and as the heating time increased. In the thermocompaction technique using System $B^{TM}$, the spreader should be heated for the minimal time and used only in the apical area. The heated spreader shouldn't inserted to the binding point of the canal and backfilling should be done with other means of minimally heated gutta percha technique.

• 유통과학연구
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• 제13권1호
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• pp.35-46
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• 2015

Purpose - This paper attempted to investigate the relationships among the perception of job insecurity and organizational effectiveness, and it examines these relationships while considering the moderating effect of trust in the manager and self-efficacy. Job insecurity is an independent variable, organizational effectiveness aspects (job satisfaction, organizational commitment, and turnover intention) are dependent variables, and trust and self-efficacy are moderators. Research design, data, and methodology - Regression analysis was used to verify the effects. The measurement items were already deemed as reliable and valid in the previous study, but for this purpose, some modifications were made. To examine the model, this study relied on the samples chosen from Korean employees in the six franchise business firms. The survey was conducted on 288 workers. Each question is based on a 5-point Likert type scale. The data were analyzed using SPSS 18.0. Results - The results of the study are summarized as follows. First, job insecurity has an influence on organizational effectiveness aspects (negatively on job satisfaction, negatively on organizational commitment, and positively on turnover intention). Second, analyzing the moderating effect of trust, trust in manager is mediated between job insecurity and organizational effectiveness aspects (on organizational commitment and on turnover intention). However, employees' trust in manager had no significant moderating effect on the job insecurity-job satisfaction relationship. Third, self-efficacy is mediated between job insecurity and organizational effectiveness aspects (on job satisfaction, on organizational commitment, and on turnover intention). Conclusions - First, it is necessary to be aware of the seriousness of employees' job insecurity in franchise firms, which have played a pivotal role in national economic growth, and to create a detailed plan for reducing insecurity and actively implementing it. To this end, the franchise companies should implement efficiency efforts such as obtaining an appropriate capacity of equipped personnel and a training program. Second, there are moderating effects of self-efficacy and trust in the relationship between job insecurity and organizational effectiveness. Depending on business conditions, stability and instability can only be experienced in the organizations of franchise companies. This can give rise to instability in employment. Therefore, it is necessary to develop and utilize a system that can be minimized with a change in the new awareness of employment instability. After all, a good leader (manager) must accumulate personal trust and build up a core competence that is necessary to become competent in the field himself. Even if you lack the material resources to improve performance, if the leader with the core competencies (e.g., technical/management /organization/marketing/design) can gain the trust of the supervisor, you can get a good organizational performance. Therefore, you should foster a healthy organizational culture through education such as leadership training and employee training to be built on trust between the leaders and the employees. In addition, you need to focus on HRD&M training in order to increase the self-efficacy of the supervisor.

• 한국식품영양과학회지
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• 제45권3호
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• pp.342-351
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• 2016

본 연구는 한국에서 식용색소로 지정되지 않은 keto-carotenoid계의 canthaxanthin에 대한 최적 분석방법을 확보하기 위해 수행되었다. HPLC-UVD를 이용한 외국의 canthaxanthin 공인분석법을 검토하여 직선성, 분리능, 민감도, 검출한계(LOD), 정랑한계(LOQ)를 도출하고, 각 실험 데이터를 비교하여 최적의 canthaxanthin 분석방법을 확보하였다. 또한 확보된 최적 분석방법에 대한 정밀도, 정확도, 회수율, 실험실 간 교차검증, 측정불확도를 산출하여 canthaxanthin 최적 분석법에 대한 타당성을 검증하였다. AOAC법, 일본 및 영국의 공인분석법을 이용하여 canthaxanthin 표준용액을 5, 10, 20, 50, 100, $300{\mu}g/mL$의 6 point로 희석한 후 얻은 검량선의 상관계수는 모두 $R^2=0.999$ 이상으로 나타나 우수한 직선성을 보였으나 분리능, 민감도, LOD, LOQ는 일본의 공인분석법이 가장 우수하였다. 일본 공인분석법의 LOD와 LOQ는 각각 0.084 mg/kg, 0.254 mg/kg으로 나타났으며, 1보다 낮은 정밀도, 100%에 가까운 정확도, $100{\pm}10%$ 사이의 회수율, 교차검증 시 세 기관의 변동계수가 5이하로 나타나 canthaxanthin 분석을 위해 가장 최적화된 방법으로 확인되었다. 또한 측정하는 중에 나타나는 불확실성을 알아보기 위하여 canthaxanthin이 함유된 가공식품을 분석하여 측정불확도를 산출한 결과 $39.5{\pm}5.29mg/kg$(95% 신뢰구간, k=2.78)으로 나타났다. 확장불확도는 측정 농도의 13.4%로 나타나 유럽연합의 기준(16% 이하)에 적합한 결과를 보였다.

• Gut and Liver
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• 제12권6호
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• pp.728-735
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• 2018

Background/Aims: The combination of nab-paclitaxel and gemcitabine (nab-P/Gem) is widely used for treating metastatic pancreatic cancer (MPC). We aimed to evaluate the therapeutic outcomes and prognostic role of treatment-related peripheral neuropathy in patients with MPC treated with nab-P/Gem in clinical practice. Methods: MPC patients treated with nab-P/Gem as the first-line chemotherapy were included. All 88 Korean patients underwent at least two cycles of nab-P/Gem combination chemotherapy (125 and $1,000mg/m^2$, respectively). Treatment-related adverse events were monitored through periodic follow-ups. Overall survival and progression-free survival were estimated by the Kaplan-Meier method, and the Cox proportional hazards regression linear model was applied to assess prognostic factors. To evaluate the prognostic value of treatment-related peripheral neuropathy, the landmark point analysis was used. Results: Patients underwent a mean of $6.7{\pm}4.2$ cycles during $6.3{\pm}4.4$ months. The median overall survival and progression-free survival rates were 14.2 months (95% confidence interval [CI], 11.8 to 20.3 months) and 8.4 months (95% CI, 7.1 to 13.2 months), respectively. The disease control rate was 84.1%; a partial response and stable disease were achieved in 30 (34.1%) and 44 (50.0%) patients, respectively. Treatment-related peripheral neuropathy developed in 52 patients (59.1%), and 13 (14.8%) and 16 (18.2%) patients experienced grades 2 and 3 neuropathy, respectively. In the landmark model, at 6 months, treatment-related peripheral neuropathy did not have a significant correlation with survival (p=0.089). Conclusions: Nab-P/Gem is a reasonable choice for treating MPC, as it shows a considerable disease control rate while the treatment-related peripheral neuropathy was tolerable. The prognostic role of treatment-related neuropathy was limited.

• 부동산연구
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• 제24권1호
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• pp.27-37
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• 2014

그동안의 고성장 인구증가시대에서의 공급량만을 늘리는 주택정책은 출생률감소와 인구의 고령화, 그리고 가구분화로 인한 1, 2인 가구의 증가와 같은 최근의 사회현상을 반영하지 못하고 있다. 또한, 이러한 주택정책은 인구가 꾸준히 성장하고 있는 대도시를 중심으로 한 정책이다. 그렇다면 지금과 같이 인구증가율이 감소하고 있는 상황에서 대도시가 아닌 중 소도시의 도시 계획 방향은 무엇일까? 구체적으로 대도시와 달리 인구가 감소 또는 정체되고 있는 도시의 주택 정책은 대도시와 어떻게 달라져야 하는가? 본 연구에서는 이러한 관점에서 도시의 주택수요를 분석하되, 인구가 증가하는 성장도시(Growing City)와 인구가 감소 또는 정체되고 있는 축소도시(Shrinking City)의 주택수요를 비교함으로서 주택정책에 필요한 시사점을 찾고자 한다. 연구결과를 종합하면, 인구가 지속적으로 감소하고 경제 활력이 성장도시보다 떨어지는 축소도시의 경우 가구의 주택소비가 정점에 이르는 연령대가 60대 후반으로, 성장도시는 80대 초반으로 나타났다. 그런데, 소득, 자산과 같은 경제변수와 가구주나이 65세 이상의 고령 1, 2인 가구더미와 청년 1, 2인 가구더미를 추가한 분석에서 축소도시는 약 5년에서 10년 정도 빠른 50대에, 성장도시는 약 20년에서 25년 정도 앞당겨진 50대 후반에서 60대 초반에 최대 주택수요를 나타내는 것으로 분석되었다. 이러한 결과는 65세 이상의 고령 1, 2인 가구 또는 청년 1, 2인 가구의 비율이 주택수요를 왜곡할 수 있음을 보여준다. 또한, 도시의 인구 및 경제학적 특성에 따라 가구의 주택 수요가 차별화될 수 있음을 나타낸다. 따라서, 경제 확장기에서 바라보았던 도시정책 그리고 주택수요정책을 이제는 개별도시의 인구 및 경제구조여건에 맞추어 재조정해야 할 필요성이 있다.