• Title/Summary/Keyword: Same distance groups

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Detection of Intrinsic Spin Alignments in Isolated Spiral Pairs

  • Koo, Hanwool;Lee, Jounghun
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.35.2-35.2
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    • 2019
  • Observational evidence for intrinsic galaxy alignments in isolated spiral pairs is presented. From the catalog of the galaxy groups identified by Tempel et al. in the flux-limited galaxy sample of the Sloan Digital Sky Survey Data Release 10, we select those groups consisting only of two spiral galaxies as isolated spiral pairs and investigate if and how strongly the spin axes of their two spiral members are aligned with each other. We detect a clear signal of intrinsic spin alignment in isolated spiral pairs, which leads to the rejection of the null hypothesis at the 99.9999% confidence level via the Rayleigh test. It is also found that those isolated pairs comprising two early-type spiral galaxies exhibit the strongest signal of intrinsic spin alignment and that the strength of the alignment signal depends on the angular separation distance as well as on the luminosity ratio of the member galaxies. Using the dark matter halos consisting of only two subhalos resolved in the EAGLE hydrodynamic simulations, we repeat the same analysis but fail to find any alignment tendency between the spin angular momentum vectors of the stellar components of the subhalos, which is in tension with the observational result. Several possible sources of this apparent inconsistency between the observational and the numerical results are discussed.

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Effect of an Unstable Surface Exercise Program using Kettlebells on the Ankle's Muscle Activity and Balance in Middle and High School Baseball Players

  • Dae Han Kang;Jae Woon Kim
    • Physical Therapy Rehabilitation Science
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    • v.11 no.4
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    • pp.579-584
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    • 2022
  • Objective: To identify the effect of unstable surface kettlebell exercises on muscle activity and balance in middle and high school baseball players. Design: Randomized controlled trial. Methods: The participants were 29 middle and high school baseball players (Unstable surface kettlebell exercises group, USKE: 15; Stable surface kettlebell exercise group, SSKE: 14). The players in the USKE group performed kettlebell exercises for 60 mins on a stable surface thrice a week for 6 weeks, and the return rack was solidified on a stable surface in the same way as the experimental group. Before and after the experiment, the participant's muscle activity of the tibialis anterior and soleus was measured. In addition, the participant's balance was evaluated by measuring the distance moved from the foot's center of pressure (COP). The paired t-test was used to compare groups before and after the experiment. The independent t-test was conducted to assess differences in the degree of change between the two groups before and after the experiment. Results: Compared to the SSKE group, the USKE group showed significant differences in the muscle activity of the tibialis anterior and soleus and the balance with the eyes open and closed. Conclusions: The players in the USKE group showed a significant difference in muscle activity and balance than in those in the SSKE group. Thus, effectively including an unstable surface in the kettlebell exercise program will help improve physical function in athletes and people with musculoskeletal disorders.

Processes in the Exercise of Power in the Conversations of Girls of About the Same Age (또래간의 담화를 통한 여아의 권력 행사 전략에 관한 연구)

  • Kweon, Mee-Ryang;Suh, Young-Hee
    • Korean Journal of Child Studies
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    • v.28 no.3
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    • pp.201-217
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    • 2007
  • Subjects included Hyomin Kim and Eunha Sohn (fictitious names) of Purum Class (a class for 5-year-olds) at 'H' Kindergarten. Subjects were selected after interviews with teachers and observation by the researcher. This study examined communication with classmates focusing on spontaneous dialog situations and functions. Results showed that Hyomin and Eunha exercised power in the art group and the math groups, respectively. The power exercise processes comprised a variety of behaviors including : to become similar with each other; to assign an exclusive seat; to act as an elder sister; to allow to do something; to keep a friend ata distance; to defend oneself; to threaten or persuade with a diversity of linguistic strategies; to teach like a teacher.

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Residents' Occupancy of Lounges and Hallways in Korean Skilled Nursing Facilities for the Elderly

  • Lee, Min-Ah
    • International Journal of Human Ecology
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    • v.7 no.1
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    • pp.13-23
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    • 2006
  • The purpose of this study was to provide basic information regarding the planning of lounge and hallway areas for skilled nursing facilities for the elderly, given that residents spend much of their time in these areas. This study examined Korean elderly residents' occupancy and behavior in lounges and hallways in order to analyze how plan type, spatial composition, and equipment affect residents. To do this, observations were conducted in five facilities that were provided to the elderly at no charge. Results indicate that a central garden offers a wide hallway area that can be used not only for strolling but also for list of activities; at the same time, it can reduce the overall rate of inactivity. A shorter distance between the lounge and hallway on the opposite side is likely to help better disperse residents' throughout the facility. Hallway corners have potential for activities that may require sofas, tables, or equipment for individual activities; they could also be used for planned interaction programs or unplanned collaboration on the part of small groups of residents.

A ROENTGENOCEPHALOMETRIC STUDY ON THE CHILDREN OF NORMAL OCCLUSION IN THE MIXED DENTITION (혼합치열기 정상교합 아동에 관한 두부방사선 계측학적 연구)

  • Lee, Hee-Ju
    • The korean journal of orthodontics
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    • v.5 no.1
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    • pp.11-19
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    • 1975
  • This study was undertaken to investigate the exact values of the cephalometric standards of Hellman dental age III B groups of Korean in the reontgenocephalometry. The subjects consisted of 25 males and the same number of females with the normal occlusion and acceptable profile. Each lateral cephalometric head film was taken with the teeth in occlusion and the Focal-film distance was 300cm. Their linear and angular measurements were made directly. The following conclusions were obtained; 1) The author made the tables of standard deviation from the measured values. 2) The degree of the facial convexity of Korean children was larger than that of the white. 3) The labial inclination of the lower central incisor in male was a little greater than that in female.

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Automatic Determination of Constraint Parameter for Improving Homography Matrix Calculation in RANSAC Algorithm

  • Chandra, Devy;Lee, Kee-Sung;Jo, Geun-Sik
    • Proceedings of the Korea Information Processing Society Conference
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    • 2014.04a
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    • pp.830-833
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    • 2014
  • This paper proposes dynamic constraint parameter to filter out degenerate configurations (i.e. set of collinear or adjacent features) in RANSAC algorithm. We define five different groups of image based on the feature distribution pattern. We apply the same linear and distance constraints for every image, but we use different constraint parameter for every group, which will affect the filtering result. An evaluation is done by comparing the proposed dynamic CS-RANSAC algorithm with the classic RANSAC and regular CS-RANSAC algorithms in the calculation of a homography matrix. The experimental results show that dynamic CS-RANSAC algorithm provides the lowest error rate compared to the other two algorithms.

The Effect of Legs Difference on The Trunk Muscle Activities With and Without Winging Scapular During Scapular Protraction in Prone-Bridge Position (엎드린 교각운동 자세에서 견갑골 전인 운동 시 익상 유무에 따른 다리 들기 차이가 체간근의 근 활성도에 미치는 영향)

  • Kim, Hee-gon;Hwang, Byeong-jun;Kim, Jong-woo
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.24 no.2
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    • pp.29-36
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    • 2018
  • Background: The purpose of this study was to investigate the effect of leg lift difference on serratus and upper trapezius when exercising in a scapula in a prone position, a typical waist stabilization exercise for subjects with a winged scapula. Method: Twenty normal adults and 20 subjects with winged scapula participated in the experiment. The surface EMG recordings were obtained from external oblique muscle and internal oblique muscle during scapula protraction exercise. The presence or absence of winging of the shoulder bone was measured using an electronic digital caliper for the distance the medial border of the scapula is lifted to the rear. In prostrate pier movement posture in both groups, both legs supporting, dominant leg lifting, and non-dominant leg lifting including the scapula protraction were conducted respectively. Results: In the results of comparison between the two groups, the dominant external oblique muscle and the non-dominant internal oblique muscle tended to increase according to the difference of the leg lifting of normal people. In the winged scapula group, internal oblique muscle showed increased muscle activity more than external oblique muscle. Conclusion: It was most effective to exercise with lifting the same position leg for strengthening the same external oblique muscle, and the opposite internal oblique muscle. Also, it is effective to exercise in prone pier movement posture for trunk stability. In addition, internal oblique muscle shows increased muscle activity in subjects with winged scapula. Therefore, appropriate adjustment of external oblique muscle and internal oblique muscle may have a positive effect on scapula dysfunction for trunk stability.

A kinematic study of young stars in Monoceros OB1 and R1 associations

  • Lim, Beomdu;Naze, Yael;Hong, Jongsuk;Yoon, Sungyong;Lee, Jinhee;Hwang, Narae;Park, Byeong-Gon;Lee, Jeong-Eun
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.50.1-50.1
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    • 2021
  • The Gaia mission opens a new window to study the kinematics and dynamics of young stellar systems in detail. The kinematic properties of young stars provide vital constraints on the formation process of their host systems. Here, we present a kinematic study of the two associations Monoceros OB1 (Mon OB1) and R1 (Mon R1). Member candidates are first selected from the published list of member candidates, a compilation of OB star catalogues, and the classification of young stellar objects with the AllWISE data. According to the conventional wisdom, we selected a total of 728 members with similar proper motions at almost the same distance. Mon OB1 and Mon R1 have high levels of substructures that are also kinematically distinct. We identify six stellar groups in these associations, of which five show a pattern of expansion. In addition, the signature of rotation is found in two stellar groups of Mon OB1. Star formation history is inferred from a color-magnitude diagram. As a result, star formation in Mon OB1 has been sustained for several million years, while Mon R1 formed at almost the same epoch as the recent star formation in Mon OB1. Some old members in the outskirt of Mon OB1 have outward motions, which rules out the previously proposed outside-in star formation scenario. Star-forming regions including Mon OB1 and Mon R1 are found along a large arc-like gas structure. Hence, the formation of these two associations may originate from the hierarchical star formation along filaments in a turbulent molecular cloud.

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Relationship Between EUV Coronal Jets and Bright Points Observed by SDO/AIA

  • Kim, Il-Hoon;Lee, Kyoung-Sun;Lee, Jin-Yi;Moon, Yong-Jae;Sung, Suk-Kyung;Kim, Kap-Sung
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.112.1-112.1
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    • 2012
  • We have investigated the relationship between EUV coronal jets and bright points observed by Solar Dynamic Observatory (SDO)/Atmospheric Imaging Assembly (AIA). For this we consider 39 EUV coronal jets from May 2010 to July 2011 in 171 A identified by Heliophysics Events Knowledgebase (HEK) which provides an automatic identification of coronal jets. We look for coronal jet-bright point pairs as follows. First, we select the size of event area as 360 arcsec * 360 arcsec where the coronal jets are located at the center of the area. Second, we select jet-bright point pairs in case that they are located at the same position or just adjacent. Third, we select jet-bright point pairs that are connected by loops each other. Otherwise, we select jet-bright points pairs as the nearest one. As a result, we present 19 coronal jet-bright point pairs. The mean distance of these pairs is 77.24 arcsec. According to their distance and morphological connection, we classify the following three groups: 1) Adjacent (6 events), 2) Loop connected (5 events), and 3) Not connected in appearance (8 events). The histogram of mutual distance has two peaks; the first peak corresponds to the first group and the other one to the second group. We compare these events with previous observations and theoretical models as well as discuss possible physical connections between jets and bright points.

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The clinical usefulness of closed reduction of nasal bone using only a periosteal elevator with a rubber band

  • Park, Young Ji;Ryu, Woo Sang;Kwon, Gyu Hyeon;Lee, Kyung Suk
    • Archives of Craniofacial Surgery
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    • v.20 no.5
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    • pp.284-288
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    • 2019
  • Background: Closed reduction of nasal fracture with various instrument is performed to treat nasal fracture. Depending on the type of nasal fracture and the situation in which it is being operated, the surgeon will determine the surgical tool. The objective of this study was to investigate whether a periosteal elevator (PE) was a proper device to perform closed reduction for patients with simple nasal fractures. Methods: From March 2018 to December 2018, 50 cases of simple nasal bone fracture underwent closed reduction performed by a single surgeon. These patients were divided into two groups randomly: nasal bone reduction was performed using only PE (freer) and nasal bone reduction was performed using Walsham, Asch forcep, and Boies elevator (non-freer, non-PE). Results: The paranasal sinus computed tomography was performed on patients before and after operation to carry out an accurate measurement of reduction distance at the same level. According to the results, the interaction between instruments and fracture types had a significant influence on reduction distance (p = 0.021). To be specific, reduction distance was significantly (p= 0.004) increased by 2.157 mm when PE was used to treat patients with partial displacement compared to that when non-PEs were used. Conclusion: Closed reduction using PE and other elevator is generally an effective treatment for nasal fracture. In partial-displacement type of simple nasal fracture, closed reduction using PE can have considerable success in comparison with using classic instruments.