• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.2949-2952
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• 2000

A new neural networks and learning algorithm are proposed in order to measure nonlinear heights of complexed road environments in realtime without pre-information. This new neural networks is Error Self Recurrent Neural Networks(ESRN), The structure of it is similar to recurrent neural networks: a delayed output as the input and a delayed error between the output of plant and neural networks as a bias input. In addition, we compute the desired value of hidden layer by an optimal method instead of transfering desired values by back-propagation and each weights are updated by RLS(Recursive Least Square). Consequently. this neural networks are not sensitive to initial weights and a learning rate, and have a faster convergence rate than conventional neural networks. We can estimate nonlinear models in realtime by ESRN and learning algorithm and control nonlinear models. To show the performance of this one. we control 7 degree of freedom full car model with several control method. From this simulation. this estimation and controller were proved to be effective to the measurements of nonlinear road environment systems.

• International Journal of Aeronautical and Space Sciences
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• 제18권3호
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• pp.565-573
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• 2017

This paper presents a multistage in-flight alignment (MIFA) method for a strapdown inertial navigation system (SDINS) suitable for moving vehicles with no initial attitude references. A SDINS mounted on a moving vehicle frequently loses attitude information for many reasons, and it makes solving navigation equations impossible because the true motion is coupled with an undefined vehicle attitude. To determine the attitude in such a situation, MIFA consists of three stages: a coarse horizontal attitude, coarse heading, and fine attitude with adaptive Kalman navigation filter (AKNF) in order. In the coarse horizontal alignment, the pitch and roll are coarsely estimated from the second order damping loop with an input of acceleration differences between the SDINS and GPS. To enhance estimation accuracy, the acceleration is smoothed by a scalar filter to reflect the true dynamics of a vehicle, and the effects of the scalar filter gains are analyzed. Then the coarse heading is determined from the GPS tracking angle and yaw increment of the SDINS. The attitude from these two stages is fed back to the initial values of the AKNF. To reduce the estimated bias errors of inertial sensors, special emphasis is given to the timing synchronization effects for the measurement of AKNF. With various real flight tests using an UH60 helicopter, it is proved that MIFA provides a dramatic position error improvement compared to the conventional gyro compass alignment.

• 한국통신학회논문지
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• 제27권4B호
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• pp.365-371
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• 2002

본 논문에서는 전자선 묘화 장비를 이용하여 게이트 길이가 0.2 $\mu\textrm{m}$ 이하인 밀리미터파용 전력 PHEMT 소자를 제작하고 DC 특성과 주파수 특성 그리고 전력 특성을 측정하고 분석하였다. PHEMT의 제작에 사용된 단위공정은 저 저항 오믹 접촉, 에어 브릿지 및 후면 가공 공정기술 등을 이용하였다. 제작된 전력용 PHEMT는 35 GHz의 중심주파수에서 4 dB의 S21 이득과 317 mS/mm의 최대 전달컨덕턴스 그리고 62 GHz의 차단주파수와 12G GHz의 최대 공진주파수를 나타내었다. 또한 측정된 전력 특성은 35.5 %의 드레인 효율과 16 dB의 최대 출력전력 그리고 4 dB의 전력 이득을 나타내었다.

• 디지털융복합연구
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• 제6권3호
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• pp.45-52
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• 2008

For the domestic digital contents, it is particularly important that the planning and mediating functions should cover the whole Industries so that dividends and assistance to reach all the way back to the primary contents-creating level, where economic risks are especially high. A proactive cooperation system or framework between the government, the businesses and research institutions, which would allow for free flow of interaction among these players, can play that role. We can broadly define cooperation frameworks into two; one between the central and the local governments and another among private-sector groups, such as companies, associations and groups. These players in the framework have differing, sometimes, conflicting views regarding the digital contents industry whether the digital contents should aim for skilled applicability or the abstract or whether the emphasis should rest on public interest or profitability. Immature competition and lack of trust among these players also give rise to such inefficiencies as overlap in investments, inexpertness and inefficient use of resources. We have proposed and realized the National Integrated Cooperation System to bridge these gaps among the major players in the industry. The National Integrated Cooperation System rests on the following major functions. The first major function of the NICS is to decipher any ambiguity that may be embedded in external Inputs by stratified role and bias. The second function is to create cooperative groups that will deal with the ambiguities based on its consequent situation. The third is a feedback function that will draw out a new cooperative way by re-feeding the capacities and the conflicts that stem from the existing organizations and strategies into cooperation and adjustment process. Our NICS has compared and evaluated with England and Australia digital content industry models under AHP(Analytic Hierarchy Process) method. NICS has turned out to be well designed and have strong points based on OECD innovation and cooperation criteria.

• 한국의상디자인학회지
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• 제15권3호
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• pp.41-50
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• 2013

This study aims to contribute to development of sanitary pad meeting customers' requirements by examining types, sorts, sizes and specifications of cloth sanitary pads currently sold in the market, and the results are as follows. First, with respect to materials of inside cloth of cloth sanitary pads, in most cases, 100% cotton knit was used as materials of the inside cloth and the pads were finished with knit cotton(including organic cotton) and woven cotton bias. Second, for the structures of the cloth sanitary pads, the Jacquard knits in the shape of beehive or waffle are mostly used. Third, the sizes of cloth sanitary pads were classified with 7 sorts were discovered that can be divided into liner, small-size, medium-size, large-size, overnight, extra overnight, accounting for the most percentage among cloth sanitary pads. Fourth, 11 sorts among cloth sanitary pads whose front and back shapes are the same were discovered, accounting for the most percentage. Fifth, cloth sanitary pads can be largely classified into a wing type, all-in-one type and insertion type, which includes subsidiary absorption layer. 9 sorts were wing types and all-in-one types, accounting for the most and percentage. Compared with the scope of the market for women's articles, there is no relevant study, so this study is expected to provide basic materials for women's articles and contribute to development of environment-friendly products as an alternative to a disposable sanitary pad which not only causes environment pollution but also has bad effects on women's health.

• ETRI Journal
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• 제24권4호
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• pp.290-298
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• 2002

We present, for the first time, a prototype active-matrix field emission display (AMFED) in which an amorphous silicon thin-film transistor (a-Si TFT) and a molybdenum-tip field emitter array (Mo-tip FEA) were monolithically integrated on a glass substrate for a novel active-matrix cathode (AMC) plate. The fabricated AMFED showed good display images with a low-voltage scan and data signals irrespective of a high voltage for field emissions. We introduced a light shield layer of metal into our AMC to reduce the photo leakage and back channel currents of the a-Si TFT. We designed the light shield to act as a focusing grid to focus emitted electron beams from the AMC onto the corresponding anode pixel. The thin film depositions in the a-Si TFTs were performed at a high temperature of above 360°C to guarantee the vacuum packaging of the AMC and anode plates. We also developed a novel wet etching process for $n^+-doped$ a-Si etching with high etch selectivity to intrinsic a-Si and used it in the fabrication of an inverted stagger TFT with a very thin active layer. The developed a-Si TFTs performed well enough to be used as control devices for AMCs. The gate bias of the a-Si TFTs well controlled the field emission currents of the AMC plates. The AMFED with these AMC plates showed low-voltage matrix addressing, good stability and reliability of field emission, and good light emissions from the anode plate with phosphors.

• Journal of Acupuncture Research
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• 제28권6호
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• pp.93-105
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• 2011

Objectives : This study aims to evaluate currently available clinical evidence for the use of acupuncture in patients with lumbar spinal stenosis in the context of Republic of Korea. Methods : Five Korean databases were searched for all clinical studies employing acupuncture for patients with lumbar spinal stenosis. The exceptions were case reports and series involving less than 10 patients from their inception to September 2011. Only studies reported in Korean databases were searched. Results : Five retrospective audits among 22 initially identified studies were eligible for analysis in this review. There was no randomized controlled trial for this topic. The number of patients varied between 15 and 119 in each audit, and all the patients analyzed were inpatients. In all the included studies, acupuncture was conducted in combination with other concomitant treatments, including moxibustion, cupping, herbal remedies, acupoint injection, Chuna, and various physical therapies. All the included audits reported symptomatic and/or functional improvements compared to baseline. None of the included audits indicated whether any adverse events were reported. Conclusions : Current evidence for the use of acupuncture in patients with lumbar spinal stenosis in the context of South Korea is based solely on five retrospective audits that are very likely prone to a high risk of bias. Thus, further prospective and methodologically sound clinical trials to overcome this huge gap between clinical practice and the available evidence for the use of acupuncture in patients with lumbar spinal stenosis are needed.

• 한국의류산업학회지
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• 제17권4호
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• pp.613-625
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• 2015

This research was conducted to provide basic data to improve expressivity required for virtual clothing to replace actual clothing. For the experiment, 6 materials were selected and 12(2 kinds of length) actual flared skirts were made. At the same time, simulations were carried out on OptiTex Runway 12.0 for 36(12 kinds of skirts $\times$ KES, FTU, KES weight/10) kinds of virtual flared skirts, which were applied with the measured property values (thickness, weight, bending, shear, friction, and stretch). Also, the study compared and analyzed the wearing images, silhouette overlapping images, and skirt length measurements of the actual and virtual skirts put on a dummy. As a result, the actual skirts showed clear distinction for each material. In contrast, virtual 1 and 2 expressed fabric 3 in the most similar way, but could not recreate the uniform, soft, and natural flare shape of the actual skirts in general. Virtual 3 formed natural flares as those of the actual skirts, and expressed fabric 1, 5, and 6 in a similar way. However, virtual 3 had too much volume and barely showed any distinction for each material. All of virtual 1, 2, and 3 expressed different flare shapes on the front and back sides of the skirt similarly to the actual skirts, and had a good visual expression for the color and texture of the materials. However, they could not effectively express the elasticity and fabric sagging in the bias direction.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.87-90
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• 2005

The FORMOSAT-3/COSMIC mission is a micro satellite mission to deploy a constellation of six micro satellites at low Earth orbits. The final mission orbit is of an altitude of 750-800 lan. It is a collaborative Taiwan-USA science experiment. Each satellite consists of three science payloads in which the GPS occultation experiment (GOX) payload will collect the GPS signals for the studies of meteorology, climate, space weather, and geodesy. The GOX onboard FORMOSAT -3 is designed as a GPS receiver with 4 antennas. The fore and aft limb antennas are installed on the front and back sides, respectively, and as well as the two precise orbit determination (POD) antennas. The precise orbit information is needed for both the occultation inversion and geodetic research. However, the instrument associated errors, such as the antenna phase center offset and even the different cable delay due to the geometric configuration of fore- and aft-positions of the POD antennas produce error on the orbit. Thus, the focus of this study is to investigate the impact of POD antenna parameter on the determination of precise satellite orbit. Furthermore, the effect of the accuracy of the determined satellite orbit on the retrieved atmospheric and ionospheric parameters is also examined. The CHAMP data, the FORMOSAT-3 satellite and orbit parameters, the Bernese 5.0 software, and the occultation data processing system are used in this work. The results show that 8 cm error on the POD antenna phase center can result in ~8 cm bias on the determined orbit and subsequently cause 0.2 K deviation on the retrieved atmospheric temperature at altitudes above 10 lan.

• 한국정보통신학회논문지
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• 제9권2호
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• pp.422-427
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• 2005

본 논문에서는 무선 네트워크 장비에도 적용 가능한 WCDMA 중계기용 전력증폭기의 선형성 및 효율을 향상시키기 위한 도허티증폭기를 구현하였다. 입력 전력의 변화에 따라 고효율 전력증폭기를 구현하고자 능동 로드풀을 이용한 도허티 기술을 이용하고 기존의 증폭기의 낮은 효율 구간에서도 우수한 선형성과 고효율을 유지하도록 설계하였다. WCDMA 주파수 대역인 2.11$\~$2.17 CHz에서 CW 1-tone 실험 결과 치대 출력 전력 52.3 dBm에서 6dBm 백 오프 지점부터 50$\%$의 전력 부가 효율을 갖게 하여 기존의 AB급에 비해 13.3$\%$ 이상의 높은 효율을 가졌다. 또한 게이트 바이어스 조절을 통하여 선형성 개선의 최적 바이어스 점을 찾은 후 도허티증폭기에서는 4dB 이상의 IMD3가 개선됨을 알 수 있었다.