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The Phytoplankton community of Namdae-stream, Yeongok-stream and of Sacheon-stream in Gangwon-do (강원도 남대천, 연곡천과 사천천의 식물플랑크톤 군집)

  • Kim, Yong-Jin;Lee, Ok-Min
    • Journal of Environmental Impact Assessment
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    • v.20 no.3
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    • pp.281-297
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    • 2011
  • The specie composition, stranding crops and the dominant species of phytoplankton were studied in three streams, Namdae-stream, Yeongok-stream and Sacheon-stream from May 2008 to February 2009. The water qualities of the three streams which run into estuary were also examined using phytoplankton indicators. As the result, the phytoplankton appeared 94 taxa in Namdae-stream, 79 taxa in Yeongok-stream and 73 taxa in Sacheon-stream, diatoms appeared the most in phytoplankton. Genus Navicula and Cymbella in diatoms appeared to be over 10 taxa in each stream, N. cryptocephala, N. cryptotenella and N. gregaria, the pollution tolerance taxa, appeared more frequent in the downstream. Due to the separation of each substrate by the rapid water velocity in the upstream, Achnanthes minutissima, a known periphyton, was dominant in upstream site at Namdae and Yeongok-stream. Some construction areas and sites of downstream of Namdae-stream, Yeongok-stream and Sacheon-stream were shown to be polluted because pollution tolerance taxa, such as Cyclotella meneghiniana, Nitzschia palea and Oscillatoria limnetica, were dominant. The total of 20 taxa phytoplankton indicators were found, composed of 16 taxa of Water pollution algae including Oscillatoria limosa, 2 taxa of Clean water algae Meridion circulare and Staurastrum puntulatum, 1 taxa of Toxic algae Microcystis aeruginosa and 1 taxa of Taste and odor algae Fragilaria construens. Water pollution indicators were appeared frequently in polluted sites of biological water quality(DAIpo, TDI) and of sites containing high trophic state index(TSI). Therefore, using the phytoplankton indicators can assess water quality through relation of biological water quality and trophic state index.

Seasonal and Latitudinal Variations of the F2-Layer during Magnetic Storms

  • Park, Yoon-Kyung;Kwak, Young-Sil;Ahn, Byung-Ho
    • Journal of Astronomy and Space Sciences
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    • v.30 no.4
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    • pp.231-239
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    • 2013
  • To identify seasonal and latitudinal variations of F2 layer during magnetic storm, we examine the change of daily averages of foF2 observed at Kokubunji and Hobart during high (2000~2002) and low (2006~2008) solar activity intervals. It is found that geomagnetic activity has a different effect on the ionospheric F2-layer electron density variation for different seasons and different latitudes. We, thus, investigate how the change of geomagnetic activity affects the ionospheric F2-layer electron density with season and latitude. For this purpose, two magnetic storms occurred in equinox (31 March 2001) and solstice (20 November 2003) seasons are selected. Then we investigate foF2, which are observed at Kokubunji, Townsville, Brisbane, Canberra and Hobart, Dst index, Ap index, and AE index for the two magnetic storm periods. These observatories have similar geomagnetic longitude, but have different latitude. Furthermore, we investigate the relation between the foF2 and the [O]/[$N_2$] ratio and TEC variations during 19-22 November 2003 magnetic storm period. As a result, we find that the latitudinal variations of [O]/[$N_2$] ratio and TEC are closely related with the latitudinal variation of foF2. Therefore, we conclude that the seasonal and latitudinal variations of foF2 during magnetic storm are caused by the seasonal and latitudinal variations of mean meridional circulation of the thermosphere, particularly upwelling and downwelling of neutral atmosphere during magnetic storm.

Effects of Treadmill Gait Training with Obstacle-Crossing on Static and Dynamic Balance Ability in Patients with Post Stroke Hemiplegia (장애물 넘기 트레드밀 보행 훈련이 편마비 환자의 정적 및 동적 균형 능력에 미치는 영향)

  • Lee, Ji-Eun;Lee, Ho-Seong
    • Journal of the Korean Society of Physical Medicine
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    • v.14 no.1
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    • pp.139-150
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    • 2019
  • PURPOSE: This study was conducted to determine the effects of treadmill gait training with obstacle-crossing on the static and dynamic balance ability of patients with post stroke hemiplegia. METHODS: Twenty-one patients with post stroke hemiplegia were divided into three groups as: treadmill gait training with obstacle-crossing (TOG, n=7), treadmill gait training without obstacle-crossing (TGG, n=7) and a control (CON, n=7). TOG and TGG performed exercise for 20 minutes, three times a week for 8 weeks. Static balance ability (stability typical, ST; weight distribution index, WDI; fourier harmony index, FHI; and fall index, FI) and dynamic balance ability (berg balance scale, BBS and timed up and go test, TUG) were measured before and after 8 -weeks in each exercise group. Statistical analyses were conducted using two-way ANOVA with repeated measures, a paired t-test, and multiple comparisons according to Tukey's HSD. RESULTS: FHI and BBS were significantly increased at TOG (p<.01) and TGG (p<.05) after 8-weeks compared to before treadmill gait training with obstacle-crossing. FHI and BBS were significantly increased at TOG compared with CON and TGG (p<.05). CONCLUSION: Treadmill gait training with obstacle-crossing was more effective than that without obstacle-crossing to improve posture control and independent daily life performance of hemiplegia patients.

The Difference of Body Mass Index According to Smart Phone Proficiency in Koreans over the Age of 60 (장노년층 스마트폰 활용능력에 따른 체질량지수 차이)

  • Kim, Joon-Sik;Kim, Jung-Woon;Hahn, Sowon;Kim, Yeon-Soo
    • The Korean journal of sports medicine
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    • v.36 no.4
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    • pp.189-196
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    • 2018
  • Purpose: The purpose of this study was to compare the difference of body mass index (BMI) to smart phone proficiency in men and women over the age of 60. Methods: Patients were divided into three groups with high (n=33), average (n=34), and low (n=33) smart phone proficiency. Fitness characteristics related to smart phone usage were evaluated by measuring cardiorespiratory endurance, grip strength, eye-hand coordination. As well, smart phone proficiency was evaluated by a self-reported questionnaire and a smart phone usability task that was composed of two categories: usage of the smartphone device itself and usage of phone applications. The differences in BMI of the subjects was analyzed by analysis of covariance adjusting for independent variables including age, smartphone usage period, eye-hand coordination, education and income. Results: There was a significant difference in BMI among the three groups after adjustment of age, eye-hand coordination, smartphone usage period, education and income. The results showed that the self-reported questionnaire showed a significant difference in BMI between high proficiency and low proficiency groups (high $24.88{\pm}2.46$, low $23.37{\pm}2.56$; p=0.037). Smart phone usability test results also showed a significant difference in BMI among the three groups (high $25.18{\pm}2.58$, low $23.15{\pm}2.6$; p=0.000 and high $25.18{\pm}2.58$, middle $23.57.7{\pm}1.69$; p=0.010). Conclusion: Our results suggest that high smart phone proficiency shows increased BMI in the elderly. This study suggests that people over the age of 60 who have high smartphone proficiency should be cautious of an increased BMI score.

Optical Properties according to BaO Addition for BaO-GeO2-La2O3-ZnO System (BaO-GeO2-La2O3-ZnO 계에 있어서 BaO 첨가량 변화에 따른 광학 특성)

  • Cho, Jaeyoung;Kim, Jinho;Kim, Sae-Hoon;Lee, Mijai
    • Korean Journal of Materials Research
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    • v.32 no.9
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    • pp.379-383
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    • 2022
  • In this study, Barium Germanium glasses were prepared with a composition of xBaO-(72-x)GeO2-8La2O3-20ZnO where x = 16.0, 18.0, 20.0, 22.0 and 24.0 mol% respectively. Their physical and optical properties, such as refractiveness index, glass transition temperature (Tg), softening temperature (Ts), transmittance and Knoop hardness were studied. The results showed that refractive index, Tg, Ts and coefficient of thermal expansion (CTE) increased with increasing BaO concentration. The refractive index of all the prepared samples was observed between 1.7811 to 1.7881. The Abbe number was calculated by formula using nd (589.3 nm), nf (656.3 nm) and nc (486.1 nm) and observed to be between 38 to 40. The Abbe number of the prepared sample was similar to that of BaO and GeO2. The transmittance of the prepared glasses was observed to be between 80 ~ 82 % throughout the range from 200 nm to 800 nm. Knoop hardness divided into seven steps were measured 5 class (≥ 450 ~ < 550) of all prepared samples.

An Unconventional Approach Considering Flexor Spasticity and Flexion Synergies of the Upper Extremity Following a Stroke: A Randomized Double-blind Pilot Study

  • Rha, Young Hyoun;Lee, Keun Hee;Shin, Jun Bum;Park, Kang Hui;Kim, Byung Sun;Ha, Jae Chan
    • Physical Therapy Korea
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    • v.29 no.2
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    • pp.147-155
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    • 2022
  • Background: Although various conventional approaches have been employed to reduce spasticity in neurological rehabilitation, only a few studies have shown scientific evidence for its effectiveness. Thus, we introduced a different concept (Ueda method) of rehabilitation therapy that can complement the limitations of conventional therapy. Objects: This study aimed to investigate the immediate effects of the application of the Ueda method on patients with spasticity after stroke via an electrophysiological study. Methods: We conducted a randomized double-blind pilot study in two rehabilitation hospitals involving 30 stroke patients who were randomly allocated to the Ueda (n = 15) and convention (n = 15) groups. Electromyographic data of six examined muscles in both upper extremities of all patients were recorded. The A-ApA index and activation ratios of upper extremity muscles were evaluated and compared between the groups to confirm post-intervention changes in upper-extremity flexor spasticity and flexion synergies. Repeated-measures analysis of variance was conducted to confirm the therapeutic effect (2 × 2) as a function of group (Ueda vs. convention) and time (pre-/post-intervention) on all outcome measures (p < 0.05). Results: In the Ueda group, the mean A-ApA index values differed significantly before and after the intervention (p = 0.041), indicating a weak evidence level; however, the effect size was medium (d = -0.503). The interaction effects of the A-ApA index between the Ueda and convention groups and between pre-intervention and post-intervention stages were significant (p = 0.012). The effect size was large (np2 = 0.220). In the Ueda group, the activation ratios of the anterior deltoid fiber significantly decreased after the intervention in all reaching tasks. Conclusion: The Ueda method reduces upper-extremity flexor spasticity and changes its synergy in stroke patients and should be considered a rehabilitation therapy for spastic stroke patients.

The Study on Characteristics of N-Doped Ethylcyclohexane Plasma-Polymer Thin Films

  • Seo, Hyeon-Jin;Jo, Sang-Jin;Lee, Jin-U;Jeon, So-Hyeon;Bu, Jin-Hyo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.540-540
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    • 2013
  • In this studying, we investigated the basic properties of N-doped plasma polymer. The N-doped ethylcyclohexane plasma polymer thin films were deposited by radio frequency (13.56 MHz) plasma-enhanced chemical vapor deposition method. Ethylcyclohexenewas used as organic precursor (carbon source) with hydrogen gas as the precursor bubbler gas. Additionally, ammonia gas [NH3] was used as nitrogen dopant. The as-grown polymerized thin films were analyzed using ellipsometry, Fourier-transform infrared [FT-IR] spectroscopy, Raman spectroscopy, FE-SEM, and water contact angle measurement. The ellipsometry results showed the refractive index change of the N-doped ethylcyclohexene plasma polymer film. The FT-IR spectrashowed that the N-doped ethylcyclohexene plasma polymer films were completely fragmented and polymerized from ethylcyclohexane.

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Feasibility of Composting Combinations of Sewage Sludge, Cattle Manure, and Sawdust in a Rotary Drum Reactor

  • Nayak, Ashish Kumar;Kalamdhad, Ajay S.
    • Environmental Engineering Research
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    • v.19 no.1
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    • pp.47-57
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    • 2014
  • The aim of this paper was to study the effect of five different waste combinations (C/N 15, C/N 20, C/N 25, C/N 30, and control) of sewage sludge coupled with sawdust and cattle manure in a pilot scale rotary drum reactor, during 20 days of the composting process. Our results showed that C/N 30 possesses a higher temperature regime with higher % reduction in moisture content, total organic carbon, soluble biochemical oxygen demand and chemical oxygen demand; and higher % gain in total nitrogen and phosphorus at the end of the composting period implying the total amount of biodegradable organic material is stabilized. In addition, $CO_2$ evolution and oxygen uptake rate decreased during the process, reflecting the stable behavior of the final compost. A Solvita maturity index of 8 indicated that the compost was stable and ready for usage as a soil conditioner. The results indicated that composting can be an alternate technology for the management of sewage sludge disposal.

Properties and Thermal Stability of PECVD a-$SiN_x$:H Films. (PECVD a-$SiN_x$:H 박막(薄膜)의 특성(特性)과 열적안정성(熱的安定性))

  • Song, Jin-Soo;Park, Joo-Suk
    • Solar Energy
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    • v.6 no.1
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    • pp.12-23
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    • 1986
  • The PECVD $SiN_x:H$ films were made from the $SiH_4-N_2$ gas mixtures under such deposition conditions as 0.01 to 1.0 of $SiH_4/N_2$ volume ratio, 0.1 to $0.8W/cm^2$ of RF power, and 100 to $400^{\circ}C$ of substrate temperature. The deposition rate, refractive index, hydrogen concentration, N/Si composition, optical gap and electric conductivity were measured, and the thermal stability and the optimum deposition conditions were investigated for the application of these films to the solar cell materials.

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A n:n Negotiation Model in the Deal based on Emotional Agent (감성적 에이전트 기반의 n:n 상거래 협상 모델)

  • 원일용;고성범
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2000.11a
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    • pp.169-177
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    • 2000
  • In general, the size of index set of the emotion-based control is smaller than that of the logic-based control. And thus, by using the concept of emotion we can control the behavior's patterns of multiple persons more softly from the global viewpoint. The principle just mentioned, we think, can be applied on fille general purpose system. In this paper we presented a n : n negotiation model in the deal based on emotional agent. Through the emotional layers of the agents we tried to show that the flexible control of the negotiation process is possible especially in case of dynamic environment.

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