• 천문학회보
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• 제46권2호
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• pp.69.2-69.2
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• 2021

We present the discovery of rare active galactic nuclei (AGNs) in nearby (z<0.05) compact elliptical galaxies (cEs) located in isolated environments. Using spectroscopic data from the Sloan Digital Sky Survey (SDSS) Data Release 12, four AGNs were identified based on the optical emission-line diagnostic diagram. SDSS optical spectra of AGNs show the presence of distinct narrow-line emissions. Utilizing the black hole (BH) mass-stellar velocity dispersion scaling relation and the correlation between the narrow L([OIII])/L(Hβ) line ratio and the width of the broad Hα emission line, we estimated the BH masses of the cEs to be in the range of 7×10⁵-8×10⁷ solar mass. The observed surface brightness profiles of the cEs were fitted with a double Sérsic function using the Dark Energy Camera Legacy Survey r-band imaging data. Assuming the inner component as the bulge, the K-band bulge luminosity was also estimated from the corresponding Two Micron All Sky Survey images. We found that our cEs follow the observed BH mass-stellar velocity dispersion and BH mass-bulge luminosity scaling relations, albeit there was a large uncertainty in the derived BH mass of one cE. In view of the observational properties of BHs and those of the stellar populations of cEs, we discuss the proposition that cEs in isolated environments are bona fide low-mass early-type galaxies (i.e., a nature origin).

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.353-360
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• 1997

The modeling on fire safety assessment for a tall and narrow atrium is carried out using a reduced and full scale atrium models based on the performances of flow behavior in and near comer fire and smoke ventilation system. The comer (or wall) effects on the flame behavior considering air entrainment into a flame was evaluated theoretically and experimentally. Temperature, upward velocity, inlet air velocity, and pressure difference between the atrium space and atmosphere were measured systematically in a reduced scale model. The performance of the modeling to estimate temperature rise and natural air ventilation volume was verified based on the experimental results. Smoke filling rate from a model fire source set at the center of a tall and narrow atrium is fastest in the other cases in which fire source set in or near a corner. This suggested that the centering of the fire source is acceptable as the fire source position to assess the fire safety design for a tall and narrow atrium.

• 산업경영시스템학회지
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• 제46권1호
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• pp.68-75
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• 2023

In an automotive plant, an automated storage and retrieval system (ASRS) synchronizes material handling flows from a part production line to an auto-assembly line. The part production line transfers parts on small-/large-sized pallets. The products on pallets are temporarily stored on the ASRS, and the ASRS retrieves the products upon request from the auto-assembly line. Each ASRS aisle is equipped with narrow-/wide-width racks for two pallet sizes. An ASRS aisle with narrow-/wide-width racks improves both storage space utilization and crane utilization while requiring delicate ASRS aisle design, i.e., the locations of the narrow-/wide-width racks in an ASRS aisle, and proper operation policies affect the ASRS performance over demand fluctuations. We focus on operation policies involving a common storage zone using wide-width racks for two pallet sizes and a storage-retrieval job-change for a crane based on assembly-line batch size. We model a discrete-event simulation model and conduct extensive experiments to evaluate operation policies. The simulation results address the best ASRS aisle design and suggest the most effective operation policies for the aisle design.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2004년도 춘계학술발표대회 논문집
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• pp.176-179
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• 2004

Space is comprised by the movements of human beings, and draws a complex locus within it. That form seems to be complex of movement around in all directions of space axis, and be ever-changing process as time goes by. Although Human are able to move uninhibitedly, the movements are restricted to a narrow sphere during locomotion. However, the pattern of these movements delineates a certain frame within the space, and provides not only visual effects but also relevance tomovement itself. Also, critically dividing and organizing this sphere is what is realized into this tangible indoor space. This study recognized importance of human being as a core of making indoor space and brought out experimental approach on relationship human with space, and visually perceptual standpoint. And this presented the recent possibility of action and attitude though sight and walking by arranging space on the basis of modern artists' perception of human body.

• 한국실내디자인학회논문집
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• 제30호
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• pp.28-34
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• 2002

We need to think that space is not static but dynamic because it becomes wide and narrow, newly appears and disappears by human's behavior. Generally such movement in a space is a thing of feeling and dynamic about movement. But it is extending the experience of the subject by scientific technique's development and anticipation about the feature. The practical movement is actively introduced into architecture and interior design scope and occurs a trial about this movement. By using four elements -a form, hue, movement, light- kineticism becomes visual arts united with art and science. It recovers the art's sociality and arises participation of spectators. In the environment and art field kineticism is not simple ostentation but a current trial for human's mind and sensitivility. Kineticism is four-dimensional space considered by human's experience and is related to an observer, or experiential subject of space. Now the space except human's mind feature re-illuminates kineticism, that is, the field of the formative arts in the early part of the 20th century and gets to be 'the consensus space'.

• 천문학회보
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• 제35권1호
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• pp.39.2-39.2
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• 2010

In this paper, I present the domestic development of near infrared camera systems for the ground telescope and the space satellite. These systems are the first infrared instruments made for astronomical observation in Korea. KASINICS (KASI Near Infrared Camera System) was developed to be installed on the 1.8m telescope of the Bohyunsan Optical Astronomy Observatory (BOAO) in Korea. KASINICS is equipped with a $512{\times}512$ InSb array enable L band observations as well as J, H, and Ks bands. The field-of-view of the array is $3.3'{\times}3.3'$ with a resolution of 0.39"/pixel. It employs an Offner relay optical system providing a cold stop to eliminate thermal background emission from the telescope structures. From the test observation, limiting magnitudes are J=17.6, H=17.5, Ks=16.1 and L(narrow)=10.0 mag at a signal-to-noise ratio of 10 in an integration time of 100 s. MIRIS (Multi-purpose InfraRed Imaging System) is the main payload of the STSAT-3 in Korea. MIRIS Space Observation Camera (SOC) covers the observation wavelength from $0.9{\mu}m$ to $2.0{\mu}m$ with a wide field of view $3.67^{\circ}{\times}3.67^{\circ}$. The PICNIC HgCdTe detector in a cold box is cooled down below 100K by a micro Stirling cooler of which cooling capacity is 220mW at 77K. MIRIS SOC adopts passive cooling technique to chill the telescope below 200K by pointing to the deep space (3K). The cooling mechanism employs a radiator, a Winston cone baffle, a thermal shield, MLI of 30 layers, and GFRP pipe support in the system. Opto-mechanical analysis was made in order to estimate and compensate possible stresses from the thermal contraction of mounting parts at cryogenic temperatures. Finite Element Analysis (FEA) of mechanical structure was also conducted to ensure safety and stability in launching environments and in orbit. MIRIS SOC will mainly perform the Galactic plane survey with narrow band filters (Pa $\alpha$ and Pa $\alpha$ continuum) and CIB (Cosmic Infrared Background) observation with wide band filters (I and H) driven by a cryogenic stepping motor.

• 대한정형도수물리치료학회지
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• 제13권1호
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• pp.67-72
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• 2007

Anatomy: The rotator cuff comprises four muscles-the subscapularis, the supraspinatus, the infraspinatus and the teres minor-and their musculotendinous attachments. The subscapularis muscle is innervated by the subscapular nerve and originates on the scapula. It inserts on the lesser tuberosity of the humerus. The supraspinatus and infraspinatus are both innervated by the suprascapular nerve, originate in the scapula and insert on the greater tuberosity. The teres minor is innervated by the axillary nerve, originates on the scapula and inserts on the greater tuberosity. The subacromial space lies underneath the acromion, the coracoid process, the acromioclavicular joint and the coracoacromial ligament. A bursa in the subacromial space provides lubrication for the rotator cuff. Etiology: The space between the undersurface of the acromion and the superior aspect of the humeral head is called the impingement interval. This space is normally narrow and is maximally narrow when the arm is abducted. Any condition that further narrows this space can cause impingement. Impingement can result from extrinsic compression or from loss of competency of the rotator cuff. Syndrome: Neer divided impingement syndrome into three stages. Stage I involves edema and/or hemorrhage. This stage generally occurs in patients less than 25 years of age and is frequently associated with an overuse injury. Generally, at this stage the syndrome is reversible. Stage II is more advanced and tends to occur in patients 25 to 40 years of age. The pathologic changes that are now evident show fibrosis as well as irreversible tendon changes. Stage III generally occurs in patients over 50 years of age and frequently involves a tendon rupture or tear. Stage III is largely a process of attrition and the culmination of fibrosis and tendinosis that have been present for many years. Treatment: In patients with stage I impingement, conservative treatment is often sufficient. Conservative treatment involves resting and stopping the offending activity. It may also involve prolonged physical therapy. Sport and job modifications may be beneficial. Nonsteroidal anti - inflammatory drugs(NSAIDS) and ice treatments can relieve pain. Ice packs applied for 20 minutes three times a day may help. A sling is never used, because adhesive capsulitis can result from immobilization.

• 천문학논총
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• 제38권2호
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• pp.75-89
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• 2023

Technosignature, previously known as SETI(search for extraterrestrial intelligence), is the scientific evidence of past or present extraterrestrial civilizations. Since NRAO's Project Ozma was performed in 1960, most of the noticeable technosignature searches have been done by radio telescopes, hoping to find strong and narrow bandwidth signals that cannot be explained by known natural processes. Recently, the Breakthrough Listen project has opened a new opportunity for technosignature by utilizing both optical telescopes, radio telescopes, and next-generation radio telescope arrays. In this review, mainly based on NASA Technosignatures Workshop (2018), we review the current trends of technosignature surveys, as well as other possible methods for detecting technosignature. Also, we suggest what the Korean community could contribute the technosignature research, including the new SETI project with Korea VLBI Network (KVN).

• Journal of Astronomy and Space Sciences
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• 제40권4호
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• pp.149-171
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• 2023

ShadowCam is a National Aeronautics and Space Administration Advanced Exploration Systems funded instrument hosted onboard the Korea Aerospace Research Institute (KARI) Korea Pathfinder Lunar Orbiter (KPLO) satellite. By collecting high-resolution images of permanently shadowed regions (PSRs), ShadowCam will provide critical information about the distribution and accessibility of water ice and other volatiles at spatial scales (1.7 m/pixel) required to mitigate risks and maximize the results of future exploration activities. The PSRs never see direct sunlight and are illuminated only by light reflected from nearby topographic highs. Since secondary illumination is very dim, ShadowCam was designed to be over 200 times more sensitive than previous imagers like the Lunar Reconnaissance Orbiter Camera Narrow Angle Camera (LROC NAC). ShadowCam images thus allow for unprecedented views into the shadows, but saturate while imaging sunlit terrain.

• 한국항공우주학회지
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• 제45권4호
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• pp.310-317
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• 2017

오늘날 다양한 나라에서 위성항법시스템을 운용, 개발하고 있다. 또한 GNSS의 성능향상을 위해 정지궤도위성을 이용하는 SBAS가 운용 중에 있다. 가장 대표적으로 사용되는 SBAS는 미국에서 개발한 GPS의 WAAS이다. SBAS에서는 사용자에게 정확성, 가용성, 연속성, 무결성을 보장하기 위해 다양한 알고리즘이 사용되고 있다. 이 중 위성에 대한 무결성을 보장하기 위한 알고리즘이 있다. 이 알고리즘은 위성오차를 추정하고 보정정보를 생성하여 사용자에게 제공한다. 여기서 위성궤도오차를 3차원으로 추정하게 된다. 이렇게 위성궤도오차를 3차원으로 추정하기 위해서는 기준국 배치가 중요하게 된다. 기준국의 배치가 넓을수록 시선각 벡터가 넓게 분포되어 추정 정확도가 향상될 수 있다. 여기서 대표적 SBAS 운영국인 미국과 한국의 지역적 특성으로 인한 분석을 수행하고자 한다. 한국은 미국에 비해 매우 협소한 지리적 특성을 가지고 있다. 따라서 3차원 위성궤도오차 추정 기법을 그대로 사용하기 어렵다. 본 논문에서는 협역지역에서 위성궤도오차를 3차원으로 추정하는 것이 아닌 스칼라로 값으로 사용하는 방식을 제안한다. 제안하는 기법은 기준국(Reference)과 위성간의 시선각 (LOS, Line-Of-Sight) 벡터에 궤도오차를 투영한 스칼라 값을 이용하는 것이다. 이 방식을 이용하여 정상상태, 고장상태의 한국과 미국지역에서 기저선 거리에 따른 오차 변화를 확인하도록 한다. 이 오차변화 차이를 비교하여 제안하는 기법의 사용 가능성을 제시한다.