• Title/Summary/Keyword: Dominant

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Fabrication of a Porous Copper Current Collector Using a Facile Chemical Etching to Alleviate Degradation of a Silicon-Dominant Li-ion Battery Anode

  • Choi, Hongsuk;Kim, Subin;Song, Hayong;Suh, Seokho;Kim, Hyeong-Jin;Eom, KwangSup
    • Corrosion Science and Technology
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    • v.20 no.5
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    • pp.249-255
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    • 2021
  • In this work, we proposed a facile method to fabricate the three-dimensional porous copper current collector (3D Cu CC) for a Si-dominant anode in a Li-ion battery (LiB). The 3D Cu CC was prepared by combining chemical etching and thermal reduction from a planar copper foil. It had a porous layer employing micro-sized Cu balls with a large surface area. In particular, it had strengthened attachment of Si-dominant active material on the CC compared to a planar 2D copper foil. Moreover, the increased contact area between a Si-dominant active material and the 3D Cu could minimize contact loss of active materials from a CC. As a result of a battery test, Si-dominant active materials on 3D Cu showed higher cyclic performance and rate-capability than those on a conventional planar copper foil. Specifically, the Si electrode employing 3D Cu exhibited an areal capacity of 0.9 mAh cm-2 at the 300th cycles (@ 1.0 mA cm-2), which was 5.6 times higher than that on the 2D copper foil (0.16 mAh cm-2).

The immediate effects of foot pressure based insole on ankle dorsiflexion range of motion, postural sway, and muscle activation in healthy adults with genu varum

  • Chun, Hye-Lim;Lee, Byoung-Hee
    • Physical Therapy Rehabilitation Science
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    • v.7 no.4
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    • pp.164-171
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    • 2018
  • Objective: The purpose of this research was to determine the immediate effects of wearing a foot-pressure-based insole (FPBI) on ankle dorsiflexion range of motion (DFROM), postural sway, and muscle activation in healthy individuals with genu varum. Design: Cross-sectional study. Methods: This study was conducted on thirteen adults, with six male and seven females subjects. The mean age was 24.08 years. Foot pressure was measured to apply the FPBI and the weight bearing lunge test was performed with the application of a flat insole (FI) and FPBI. Examination was randomly performed in four conditions to measure both postural sway and muscle activation. All participants applied both the FI and FPBI with four conditions. The four conditions were as follows: 1) Romberg test posture with eyes closed, 2) Romberg test posture with eyes opened, 3) dominant single leg standing with eyes opened, and 4) non-dominant single leg standing with eyes opened. Results: For ankle DFROM between the FI and FPBI, a significant increase was observed in both the dominant and non-dominant leg (p<0.05). For postural sway between the FI and FPBI in the Romberg test posture with eyes closed and dominant single leg standing with eyes opened conditions, a significant decrease was observed (p<0.05). However, the postural sway between FI and FPBI in the Romberg test posture with eyes opened and non-dominant single leg standing with eyes opened, no significant decrease was observed. Also, there were no significant effects on muscle activation between the application of the FI and FPBI. Conclusions: The result showed that FPBI immediately improved ankle DFROM and postural sway. It seems that FPBI may improve genu varum in healthy individuals with genu varum.

The Influence of Augmented Reality based Knee Exercise in Short Period on Range of Motion and Balance - Pilot study (증강현실 기반의 단기간 무릎운동이 관절가동범위와 균형에 미치는 영향 - 예비연구)

  • Im, JongHun;Yu, JaeHo
    • Archives of Orthopedic and Sports Physical Therapy
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    • v.14 no.2
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    • pp.1-8
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    • 2018
  • Purpose: This study investigated the effect of the augmented reality (AR)-based knee joint short period exercise program and used a motion analyzer with a 3D camera to determine the range of motion and dynamic balance and further investigate the effects of therapeutic exercise on patients. Methods: This study used AR-based motion analysis and a Y-balance test to measure the range of motion (ROM) of each joint: the hip joint and the knee joint. After the measurements, an exercise program was applied to the subjects, using the knee motion program function, and the muscles of the quadriceps femoris and the hamstring were stretched or strengthened. Results: Our results showed knee joint extension at the dominant hip joint flexion position. While there was no significant difference (p>.05) at this position, there were significant differences in the non-dominant hips, unbalanced knee joint flexion, and superior knee joint flexion (p<.05). The Y-balance test using the non-dominant leg supported by the dominant legs showed that the absolute reach was $69.70{\pm}7.06cm$ before the exercise, and the absolute reach after the exercise was $77.56{\pm}6.09cm$ (p<.05). Conclusions: There was a significant difference when the movement of the lower limbs supported the superior limbs, and a significant difference was found in the ROM when the non-dominant side supported the dominant side. Therefore, the AR-based exercise program improves the balance of the human body and the range of motion of the joints, and research that aims to improve patients abilities should continue.

Plant co-occurrence patterns and soil environments associated with three dominant plants in the Arctic

  • Deokjoo Son
    • Journal of Ecology and Environment
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    • v.47 no.1
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    • pp.1-13
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    • 2023
  • Background: The positive effects of Arctic plants on the soil environment and plant-species co-occurrence patterns are known to be particularly important in physically harsh environments. Although three dominant plants (Cassiope tetragona, Dryas octopetala, and Silene acaulis) are abundant in the Arctic ecosystem at Ny-Ålesund, Svalbard, few studies have examined their occurrence patterns with other species and their buffering effect on soil-temperature and soil-moisture fluctuation. To quantify the plant-species co-occurrence patterns and their positive effects on soil environments, I surveyed the vegetation cover, analyzed the soil-chemical properties (total carbon, total nitrogen, pH, and soil organic matter) from 101 open plots, and measured the daily soil-temperature and soil-moisture content under three dominant plant patches and bare soil. Results: The Cassiope tetragona and Dryas octopetala communities increased the soil-temperature stability; however, the three dominant plant communities did not significantly affect the soil-moisture stability. Non-metric multidimensional scaling separated the sampling sites into three groups based on the different vegetation compositions. The three dominant plants occurred randomly with other species; however, the vegetation composition of two positive co-occurring species pairs (Oxyria digyna-Cerastium acrticum and Luzula confusa-Salix polaris) was examined. The plant species richness did not significantly differ in the three plant communities. Conclusions: The three plant communities showed distinctive vegetation compositions; however, the three dominant plants were randomly and widely distributed throughout the study sites. Although the facilitative effects of the three Arctic plants on increases in the soil-moisture fluctuation and richness were not quantified, this research enables a deeper understanding of plant co-occurrence patterns in Arctic ecosystems and thereby contributes to predicting the shift in vegetation composition and coexistence in response to climate warming. This research highlights the need to better understand plant-plant interactions within tundra communities.

Distribution of Ants(Hymenoptera: Formicidae) by Vegetation in Mt. Gariwangsan from Korea (식생별에 따른 가리왕산의 개미분포)

  • Lyu, Dong-Pyo
    • Korean Journal of Environment and Ecology
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    • v.27 no.2
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    • pp.204-208
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    • 2013
  • The ant fauna in Mt. Gariwangsan was composed of 39 species 24 genera 5 subfamilies. The collected ants in Mt. Gariwangsan were Subfamily Myrmicinae(16 species 11 genera), Subfamily Formicinae(15 species 5 genera), Subfamily Ponerinae(6 species 4 genera), Subfamily Amblyoponinae(1 species 1 genera), and Subfamily Dolichoderrinae(1 species 1 genera). Ant fauna by vegetation in Mt. Gariwangsan, 36 species 23 genera were collected in broadleaf tree areas in which Quercus mongolica, Fraxinus rhynchophylla, Tilia amurensis, and Cornus controversa were dominant species. Paratrechina flavipes and Myrmica kotokui were dominant species. 13 species 12 genera were collected only in broadleaf tree areas. In the coniferous tree areas where Pinus densiflora, Pinus korainensis, and Larix kaempferi were dominant, 24 species 15 genera of ants in total were collected. Pachycondyla chinensis and Paratrechina flavipes were dominant species. 4 species 3 genera were collected only in the coniferous tree areas. Paratrechina flavipes was dominant even in the areas in which Camponotus japonicas and Formica japonica had been assumed to be dominant. Specifically, the higher the land was, the rarer Ponerinae and Dolichoderinae were observed. The common species observed in both areas were 20 species 13 genera. Of these ants, Paratrechina flavipes(Subfamily Formicinae) and Myrmica kotokui(Subfamily Myrmicinae) were distinctive ants. With regard to the current state of colony of these species, Paratrechina flavipes was dominant in lowland areas. Myrmica kotokui, on the other hand, was dominant in highland areas.

Variation Analysis of Phytoplankton Communities in Northern Gamak Bay, Korea (북부 가막만의 식물플랑크톤 군집 변동 해석)

  • Oh, Seok-Jin;Park, Jong-Sik;Yoon, Yang-Ho;Yang, Han-Soeb
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.15 no.4
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    • pp.329-338
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    • 2009
  • Using physiological data which had been already published, we investigated variation of phytoplankton communities due to changes of marine environmental factor at 2 stations of northern Gamak Bay from November 2007 to September 2008. Dominant species (occupied species above 10%) were dinoflagellates 1 species and diatom 11 species. Diatom Skeletonema costatum was observed as dominant species during the periods except in summer (i.e. July and August), especially, which occupied above 90% in December. On the other hand, dominant species during summer were diatom Eucampia zodiacus and Chaetoceros spp., Considering the results of other physiological studies, S. costatum might be non-dominant species during summer by following reasons 1) growth rate of E. zodiacus might be taster than that of S. costatum under the temperature during summer although both S. costatum and E. zodiacus are eurythermal and euryhaline species. 2) Species as E. zodiacus characterized by low affinity with light might have a chance to be dominant with increasing optical transparency due to low suspended solids in July. 3) In aspect of nutrition, species of growth strategist as S. costatum could be dominant in relatively low concentration of phosphate and species of storage strategist as E. zodiacus could be dominant in relatively high concentration of phosphate during summer in this study area. In order to understand the phytoplankton dynamics in detail, the physiological informations about strains isolated from this study area are necessary because physiological conditions are different depending on isolated area.

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The Effect of Vision and Proprioception on Lumbar Movement Accuracy (시각과 고유수용성 감각이 요부 운동의 정확도에 미치는 영향)

  • Sim, Hyun-Po;Yoon, Hong-Il;Youn, I-Na
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.13 no.2
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    • pp.31-44
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    • 2007
  • The purposes of this study were to examine the normal lumbar proprioception and identify the effect of vision and proprioception on lumbar movement accuracy through measuring a reposition error in visual and non-visual conditions and to provide the basic data for use of vision when rehabilitation program is applied. The subjects of this study were 39 healthy university students who have average physical activity level. They were measured the ability to reproduce the target position(50% of maximal range of motion) of flexion, extension, dominant and non-dominant side flexion in visual and non-visual conditions. Movement accuracy was assessed by reposition error(differences between intended and actual positions) that is calculated by the average of absolute value of 3 repeated measures at each directions. The data were analysed by paired samples t-test, independent samples t-test, and repeated measures ANOVA. The results were as follows : 1. Movement accuracy of flexion, extension, dominant side flexion, and non-dominant side flexion was increased in visual condition. 2. There were no differences in the lumbar movement accuracy between sexes in visual and non-visual conditions. 3. In non-visual condition, the movement in coronal plane(dominant and non dominant side flexion) is more accurate than that in sagittal plane(flexion and extension). 4. In non-visual condition, there were no differences in the lumbar movement accuracy between dominant and non-dominant side flexion. In conclusion, this study demonstrates that the movement is more accurate when the visual information input is available than proprioception is only available. When proprioception is decreased by injury or disease, it disturbs the control of posture and movement. In this case, human controls the posture and movement by using visual compensation. However it is impossible to prevent an injury or trauma because most of injuries occur in an unexpected situation. For this reason, it is important to improve the proprioception. Therefore, proprioceptive training or exercise which improve the ability to control of posture and movement is performed an appropriate control of permission or interception of the visual information input to prevent an excessive visual compensation.

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Measuring Changes of Dominance in Designs of Mobile Phones (휴대폰 디자인에 있어서 지배성 변화 측정)

  • Park, Sang-June;Lee, Yu-Ri
    • Science of Emotion and Sensibility
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    • v.13 no.1
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    • pp.91-102
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    • 2010
  • This study investigates the dominant degree of product design factors through the process of change of design factors. The previous research suggested a concrete measurement method of dominant designs, but it did not investigate empirically the degree of dominance due to the limited data for changes of designs. In this research, thus, after collecting design data of mobile phones and we measured the dominance and structure change of the designs by year. The analyses showed the following two things. First, in design factors of mobile phone the dominance on the body form and the edge grows more and both of them as dominant design factors tend to converge into the rectangular body form and the round edge, respectively. Second, the dominance on other design factors(e.g. the button type, the open type, whether or not to have digital multimedia broadcasting(DMB) and video telephony functions, the combination of colors and the body color) increases and decreases; and hence, design levels tend to diverge. In conclusion, the measurement of dominance on product design factors contributes to marketing managers and designers who are required to establish a strategy for products under the rapidly changing circumstances of market. This research aims to provide those managers and designers with a guide line for a successful development of new product to prepare for the dominant design from this empirical study.

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The Analysis of Phytoplankton Community Structure in the Middle-Lower Part of the Nakdong River (낙동강 중·하류의 식물플랑크톤 군집구조 분석)

  • Son, Hee-Jong
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.6
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    • pp.430-435
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    • 2013
  • A seasonal variation of phytoplankton community in the middle-lower part of the Nakdong River was studied in four sampling stations at monthly intervals from January to December 2012. We identified 40 genera 72 species of phytoplankton. Among these, diatoms were 36 species (50.0%), green algae 20 species (27.8%), blue-green algae 9 species (12.5%) and others 7 species (9.7%), respectively. The phytoplankton standing crops were recorded a maximum of 29,640 cells/mL at the Mulgeum (St. 4) in June and a minimum of 236 cells/mL at the Goryung (St. 1) in October. Also, Standing crops were increased with proceeding from middle part to lower part. Ecological important species were Stephanodiscus hantzschii, Cyclotella meneghiniana, Synedra acus, Aulacoseira granulata, Pediastrum sp. and Microcystis aeruginosa. Seasonal succession of phytoplankton represented that Stephanodiscus hantzschii was dominant species in winter, Cyclotella meneghiniana, Synedra acus was dominant species in spring, Microcystis aeruginosa, Cyclotella meneghiniana, Fragilaria crotonensis, Synedra acus, Aulacoseria granulata was dominant species in summer, and Aulacoseria granulata, Cyclotella meneghiniana, Fragilaria crotonensis was dominant species in autumn. In the community analysis, diversity index and dominant index were higher May~July and December~February, respectively. Also, diversity index and dominant index were decreased and increased with proceeding from middle part to lower part.

Radiographic Changes of the Medial Epicondyle in Little League Baseball Player (청소년기 야구선수의 주관절 내상과의 방사선학적 변화)

  • Choi Chang-Hyuk;Eum Dong-Hwan
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.1 no.1
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    • pp.43-48
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    • 2002
  • Purpose : We evaluated radiographic changes and clinical manifestations of the elbow joint to identify the effects of the throwing between dominant and non-dominant arms. Materials and Methods : A hundred and five little leaguer’s baseball player in 5 elementary school and 2 middle school were evaluated for clinical symptoms and radiographic changes about elbow joint. Mean age was 12 years old and average periods of exercise were 32 months. Elbow functions were evaluated using ASES standardized assessment form and radiographic changes of medial epicondyle were examinated for enlargement, separation of the apophyses, fragmentation and irregularity. Results : Thirty seven players (35$\%$) were complained pain with throwing and the average score was 4.8 using visual analog scale. There were no significant differences in range of motion except flexion angle, valgus angle, and strength between dominant arm and non-dominant arm. Valgus laxity was more prominent in dominant arm. Ulnohumeral tenderness, radiocapitellar tenderness and medial flexor origin tenderness were in 18, 6, and 17 cases respectively in dominant arm. Medial epicondyle was enlarged in dominant arm with 13.0 by 6.3 mm compared to non-dominant arm with 11.7 by 6.1 mm. Apophyseal separation was 0.8 mm in dominant arm and 0.5 mm in non-dominant arm. Fragmentation and irregularity were 14 (13$\%$) and 25 (24$\%$) cases respectively in dominant arm. Conclusion : In little league baseball player, it needs usage of ball and bat with appropriate weight, and careful conditioning programs through throwing exercise in order to avoid elbow injuries.

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