• 한국가스학회지
• /
• 제4권4호
• /
• pp.1-5
• /
• 2000

[ $H_2S$ ]를 포함하는 액화천연가스(Liquified Natural Gas)의 기-액 조성을 noncubic 형태인 Modified-Benedict-Web-Robin EOS로 예측하였고, 그 결과를 대표적 cubic형태의 Peng-Robinson, Soave-Redlich-Kwong EOS로 예측한 기-액 조성과 비교 검토하였다.

• 한국전기전자재료학회논문지
• /
• 제13권9호
• /
• pp.770-775
• /
• 2000

A new photo-polymer material of the copoly (PM4Ch-ChMA), copoly (poly (4-methacryloyloxy)chalcone-cholesteryl methacrylate) for homeotropic alignment was synthesized and the electro-optical (EO) performance for the photo-aligned vertical-aligned (VA)-LC display (LCD) was studied. Good thermal stabilities of synthesized copolymer were obtained by TGA(Thermogravimetric Analysis) measurement. Good voltage-transmittance (V-T) and response time characteristics for the photo-aligned VA-LCD with polarized UV exposure in oblique direction($\theta$$_{i}$=30$^{\circ}$) on a copolymer-1 (2%) surfaces for 1 min were observed. but, light leakage in the off-state was observed. Therefore, we achieved excellent V-T and response time characteristics for the photo-aligned VA-LCD with UV exposure on a copolymer-3 (30%) surfaces for 3 min.n.

• 한국전산유체공학회지
• /
• 제22권1호
• /
• pp.37-42
• /
• 2017

Infrared signals are frequently used to detect objects exposed to wide variety of environmental conditions. Detection by infrared signature is accomplished by distinguishing objects by using the IR radiant contrast between objects and the background. There are several methods of estimating the IR radiant contrast. The inverse distance weighting method, which is one of the IR radiant contrast estimation method using the effect of distance from objects, is known to be an effective way to analyze radiant contrast for complex backgrounds. However this method has a disadvantage of requiring a long calculation time. In this study we propose a statistical method of estimating the IR radiant contrast by using randomly selected pixels of arbitrary number among background pixels to reduce calculation time. Some measured IR images in MWIR and LWIR regions are used to test the applicability of the method proposed and we found that the proposed method is very effective in determining the IR radiant contrast showing very rapid estimation with minar accuracy loss.

• 한국전산유체공학회지
• /
• 제22권1호
• /
• pp.88-94
• /
• 2017

The IR signal entering into a sensor is composed of the following components: the self-emitted component directly from the object surface, the reflected components of the solar and sky irradiance at the object surface, and the scattered component by the atmosphere without reference to any object surfaces. The self-emitted and reflected components from the object can be lowered by the atmospheric layer between the object and the IR sensor. The principle factors influencing the atmospheric transmittance are the air temperature, the relative humidity and the observation distance. Previous studies on IR signal transmission through the atmosphere are focused on uniform atmospheric conditions and the non-uniform nature of the atmosphere was not properly treated in modeling. In this study, we use the local atmospheric transmittance to simulate the non-uniform atmosphere in analyzing the IR signal from the object surface. The results show that the nonuniform analysis of the atmosphere becomes more important as the wavelength of IR signal increases.

• 한국어류학회지
• /
• 제35권1호
• /
• pp.57-63
• /
• 2023

본 연구에서는 2018년 2~3월 제주도 남부해역에서 Bathylagidae에 속하는 Lipolagus ochotensis 자어 4개체(체장 13.4~21.3 mm)를 봉고네트로 채집하였다. L. ochotensis 자어는 몸이 길게 신장되었으며, 체고는 낮고, 눈이 돌출되며, 몸의 후반부에 흑색소포가 나 있고, 등지느러미가 몸 중앙에 위치하는 특징을 가진다. 미토콘드리아 DNA COI의 염기서열 625 bp를 분석한 결과, L. ochotensis 성어와 97.6%로 매우 가깝게 나타났다. 국내 처음 보고되는 본 종의 새로운 과명으로 "심해빙어과", 속명으로 "검은빙어속", 국명으로 "검은뺨빙어"를 각각 제안한다.

• 대한핵의학회:학술대회논문집
• /
• 대한핵의학회 2005년도 제44차 추계학술대회 및 총회
• /
• pp.347.1-347.1
• /
• 2005

• 한국통신학회논문지
• /
• 제40권6호
• /
• pp.1081-1090
• /
• 2015

This work proposes a theoretic framework for the performance assessment of an access point in the IP network that accommodates MD (Machine Data) and HD (Human Data). First, we investigate typical resource allocation methods in LTE for MD and HD. After that we carry out a Max-Min analysis about the surplus and deficiency of network resource seen from MD and HD. Finally, we evaluate the performance via numerical experiment.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
• /
• pp.1673-1674
• /
• 2006

The most ideal light source known to the mankind is sunlight. Therefore, whenever an artificial light source is needed in a dark place such as in a shadowed houses, the utmost goal is to find an artificial light characteristics of which approaches that of sunlight. On this ground, we have investigated a Neodymium lamp as a possible substitute for sunlight. Especially, the local and the color rendering, a life expectancy, and the overall efficiency are carefully studied.

• The Journal of Korean Physical Therapy
• /
• 제28권5호
• /
• pp.264-268
• /
• 2016

Purpose: This study was conducted to investigate the effects on muscle thickness and balance ability after performing plank exercise on various surface types. Methods: In this study, there were thirty healthy participants. Participants were randomly distributed into three groups, a control group (n=10), sling group (n=10), and ball group (n=10). All participants performed plank exercises three times a week for four weeks. Plank exercises consisted of five sets of 30 seconds each with a one minute break between each set. Muscle thickness of the transverse abdominis (TrA), internal oblique (IO), and external oblique (EO) was measured using an ultrasound diagnostic apparatus and balance was measured using I-balance. Results: Evaluation of muscle thickness revealed that the IO and EO muscle of the ball group changed significantly relative to the control group (p<0.05). However, there were no significant changes in balance. Conclusion: The results revealed that performing plank exercise on a ball is more effective among various types of surfaces.

• Smart Structures and Systems
• /
• 제33권3호
• /
• pp.227-241
• /
• 2024

Safety and structural integrity of civil structures, like bridges and buildings, can be substantially enhanced by employing appropriate structural health monitoring (SHM) techniques for timely diagnosis of incipient damages. The information gathered from health monitoring of important infrastructure helps in making informed decisions on their maintenance. This ensures smooth, uninterrupted operation of the civil infrastructure and also cuts down the overall maintenance cost. With an early warning system, SHM can protect human life during major structural failures. A real-time online damage localization technique is proposed using only the vibration measurements in this paper. The concept of the 'Degree of Scatter' (DoS) of the vibration measurements is used to generate a spatial profile, and fractal dimension theory is used for damage detection and localization in the proposed two-phase algorithm. Further, it ensures robustness against environmental and operational variability (EoV). The proposed method works only with output-only responses and does not require correlated finite element models. Investigations are carried out to test the presented algorithm, using the synthetic data generated from a simply supported beam, a 25-storey shear building model, and also experimental data obtained from the lab-level experiments on a steel I-beam and a ten-storey framed structure. The investigations suggest that the proposed damage localization algorithm is capable of isolating the influence of the confounding factors associated with EoV while detecting and localizing damage even with noisy measurements.