• 비파괴검사학회지
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• 제32권5호
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• pp.540-544
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• 2012

위상배열 기술에 기반을 둔 통상의 초음파검사에서처럼, 자왜형 원거리 초음파검사에서도 실시간 수신신호 처리를 위해 복잡한 전자회로들을 사용하여왔다. 본 연구는 위상 보상, 노이즈 필터링, 파형 변환 등과 같은 필수적인 작업들을 기존의 하드웨어 접근보다는 소프트웨어 접근을 이용하여 수행할 때, 보다 유연하고 효율적인 실시간 신호처리가 가능해진다는 것을 보여준다. 이는 비용효율적인 원거리 초음파검사 시스템 구축과 검사 결과 분석에 기여할 것이다.

• ETRI Journal
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• 제45권4호
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• pp.570-580
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• 2023

Sensor nodes are the most significant part of a wireless sensor network that offers a powerful combination of sensing, processing, and communication. One major challenge while designing a sensor node is power consumption, as sensor nodes are generally battery-operated. In this study, we proposed the design of a low-power, long range-based wireless sensor node with flexibility, a compact size, and energy efficiency. Furthermore, we improved power performance by adopting an efficient hardware design and proper component selection. The Nano Power Timer Integrated Circuit is used for power management, as it consumes nanoamps of current, resulting in improved battery life. The proposed design achieves an off-time current of 38.17309 nA, which is tiny compared with the design discussed in the existing literature. Battery life is estimated for spreading factors (SFs), ranging from SF7 to SF12. The achieved battery life is 2.54 years for SF12 and 3.94 years for SF7. We present the analysis of current consumption and battery life. Sensor data, received signal strength indicator, and signal-to-noise ratio are visualized using the ThingSpeak network.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1758-1761
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• 1997

The problem of long range capacity expansion planing for chemical processing network under uncertain demand forecast secnarios is addressed. This optimization problem involves capactiy expansion timing and sizing of each chemical processing unit to maximize the expected net present value considering the deviation of net present values and the excess capacity over a given time horizon. A multiperiod mixed integer nonlinear programming optimization model that is both solution and modle robust for any realization of demand scenarios is developed using the two-stage stochastic programming algorithm. Two example problems are considered to illustrate the effectiveness of the model.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2019년도 춘계학술대회
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• pp.139-141
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• 2019

본 논문은 무인이동체를 위한 관제시스템을 사용 하기위해 최근 다양한 연구가 진행되어 왔던 LoRa망 적용을 제안한다. LoRa(Long Range)는 최대 30km정도의 넓은 커버리지를 가지고 있으며, 대규모 저전력 장거리 무선통신이 특징이다. 이미 LoRa는 다양한 산업에 적용되어 연구되어 오고 있다. 또한 LoRa망을 활용하여 무인이동체들의 관제시스템에 적용시켜 다양한 기능에 대한 연구를 제안한다.

• Clinics in Shoulder and Elbow
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• 제18권4호
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• pp.229-236
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• 2015

Background: Twenty-six patients (12 male and 14 female) with symptomatic scapular winging caused by serratus anterior dysfunction were managed by split pectoralis major tendon transfer (sternal head) with autogenous hamstring tendon augmentation from 1998 to 2006. Methods: Twenty-five patients showed positive results upon long thoracic nerve palsy on electromyography. The mean duration of symptoms until surgery was 48 months (range, 12-120 months). Four patients had non-traumatic etiologies and 22 patients had traumatic etiologies. On follow-up assessment for functional improvement, a Constant-Murley score was used. Twenty-one patients were completely evaluated, while five patients who had less than 12 months of follow-up were excluded. Results: Pain relief was achieved in 19 of the 21 patients, with 20 patients showing functional improvement. The pain scores improved from 6.0 preoperatively to 1.8 postoperatively. The mean active forward elevation improved from $108^{\circ}$ (range, $20^{\circ}-165^{\circ}$) preoperatively to $151^{\circ}$ (range, $125^{\circ}-170^{\circ}$) postoperatively. The mean Constant-Murley score improved from 57.7 (range, 21-86) preoperatively to 86.9 (range, 42-98) postoperatively. A recurrence developed in one patient. Of the 21 patients, ten had excellent results, six had good results, four had fair results, and one had poor results. Conclusions: Most patients with severe symptomatic scapular winging showed functional improvement and pain relief with resolution of scapular winging.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.208-212
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• 2003

An airborne radar is an essential aviation electronic system of the helicopter to perform various missions in all-weather environments. This paper presents the conceptual design results of the multi-mode pulsed Doppler radar system testbed model for helicopter. Due to the inherent flight nature of the hovering vehicle which is flying in low-altitude and low speed, as well as rapid maneuvering, the moving clutters from the platform should be suppressed by using a special MTD (Moving Target Detector) processing. For the multi-mode radar system model design, the flight parameters of the moving helicopter platform were assumed: altitude of 3 Km, average cruising velocity of 150knots. The multi-mode operation capability was applied such as short-range, medium-range, and long-range depending on the mission of the vehicle. The nominal detection ranges is 30 Km for the testbed experimental model, but can be expanded up to 75 Km for the long range weather mode. The detection probability of each mode is also compared in terms of the signal-to noise ratio of each mode, and the designed radar system specifications ate provided as a design results.

• Clinical Endoscopy
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• 제56권6호
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• pp.726-734
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• 2023

Background/Aims: Endoscopic stenting for stricturing Crohn's disease (CD) is an emerging treatment that achieves more persistent dilatation of the stricture over time than endoscopic balloon dilatation (EBD). We aimed to explore the efficacy and safety of stenting for the treatment of CD strictures. Methods: A systematic electronic literature search was performed (PROSPERO; no. CRD42022308033). The primary outcomes were technical success, efficacy, complication rate, and the need for further interventions due to reobstruction. The outcomes of partially covered self-expanding metal stents (PCSEMS) with scheduled retrieval after seven days were also analyzed. Results: Eleven eligible studies were included in the review. Overall, 173 patients with CD were included in this study. Mean percentage of technical success was 95% (range, 80%-100%), short-term efficacy was 100% in all studies, and long-term efficacy was 56% (range, 25%-90%). In patients with a scheduled PCSEMS retrieval, the long-term efficacy was 76% (range, 59%-90%), the mean complication rate was 35% (range, 15%-57%), and the major complication rate was 11% (range, 0%-29%). Conclusions: Endoscopic stenting with scheduled PCSEMS retrieval may be considered a feasible second-line treatment for short CD strictures to postpone surgery. However, larger head-to-head prospective studies are needed to understand the role of stenting as an alternative or additional treatment to EBD in CD.

• 한국안광학회지
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• 제18권4호
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• pp.495-501
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• 2013

목적: 본 연구는 망원경과 바이프리즘(biprism)을 이용하여 골퍼로부터 깃대까지의 거리를 정확히 측정할 수 있는 골프 거리측정기를 개발하기 위한 것이다. 방법: 망원경내부에 이동 가능한 바이프리즘을 포함시켜 골프거리측정기를 제작하였으며. 20~200 m 거리에서 제작된 거리측정기의 정확도를 분석하였다. 결과: 바이프리즘의 위치에 따라 거리를 계산할 수 있는 방정식을 유도하였으며 개발된 골프거리측정기를 이용하여 성공적으로 거리를 측정할 수 있었다. 2 ${\Delta}$의 바이프리즘이 짧은 거리의 측정에서는 유용했지만 먼 거리의 측정에서는 정확도가 떨어지는 것으로 나타났으며 먼 거리의 측정에는 0.5 ${\Delta}$이 더 유용한 것으로 나타났다. 먼 거리를 측정하기 위하여 바이프리즘이 대물렌즈의 초점부근으로 접근할 때 상이 나빠지는 현상이 나타났으며, 이러한 약점을 보완하기 위하여 다층형 바이프리즘을 개발하였다. 결론: 바이프리즘을 이용하여 손떨림에 구애받지 않고 거리를 잘 측정할 수 있었으며 유도한 거리계산 방정식이 유용함을 확인하였다. 먼 거리를 측정하기 위하여 바이프리즘이 대물렌즈의 초점부근으로 접근했을 때 새로이 고안된 다층형 바이프리즘이 일반적인 바이프리즘보다 유용하다는 것을 확인하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.488-491
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• 2008

The variations of the TFT characteristics in AMOLEDs result in the decrease of the uniformity of the displays. Measurement of the long-range uniformity (LRU) is straightforward. However, there is no method for measuring the short-range uniformity (SRU) yet. Quantifying the SRU is important in evaluating various TFT backplanes and compensation circuits. We propose new methods for measuring SRU.

• 보건의료산업학회지
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• 제5권3호
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• pp.13-23
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• 2011

This paper investigated the operating environment for the representative of each agency and the facility workers on the basis of analytical result of recognition changes of the operating environment changes under the operating the long-term care insurance. It was described plans to take positive effect on the operating as follows. The first, on the result of regression analysis, the service administrative range takes the biggest effect on the general recognition of executing the long-term care insurance off and on. The affirmative recognition of the service administrative range had the general recognition on the system be positive effect. But the operator of facility asserts that the care manager's professionalism related quality of service be strengthened. The second, on the result of regression analysis, in the financial accounting administrative it is revealed the more positive recognition it is, the more positive effects it has. From the difference verification of an operation size from operation subject, the small operation size and personal facility recognize the long term care insurance positively. On the other side the facilities where the operation size is big recognize the system negatively. The long-term care facility should rearrange a support program newly and the government needs to promote the donation activity, because it is needed to reduce the financial burden of facilities.