• 제목/요약/키워드: stabilization height

검색결과 106건 처리시간 0.024초

암면배지내 인공 zeolite 형 각종 이온교환제 처리가 온실멜론의 이온교환능에 미치는 영향 (Effects of Artificial Zeolite and Various ion Exchangers Supplemented in Rockwool on the Ion Exchangability of Muskmelon)

  • 장홍기;정순주
    • 생물환경조절학회지
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    • 제5권1호
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    • pp.43-49
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    • 1996
  • 본 실험은 인공 zeolite 및 각종 이온교환제를 암면슬라브내에 첨가하므로서 완형능력을 부여하여 온실멜론의 암면재배에 대한 이온 교환능 및 흡착능의 작용기작을 비교검사하고자 수행하였다. 1. 이온교환제의 처리에 따른 멜론의 생육특성중 초장은 대조구인 원시 1/2단위에서 124cm인데 대해 Ca형 인공zeolite에서는 131,2cm로 켰으며 경 및 엽의 생체중에서도 같은 경향이 보였다. 2. 과실중은 인공 zeolite를 첨가한 경우에 무거워지는 경향을 나타냈으며, 당도 및 외관은 처리에 따른 차이가 거의 보이지 않았다. 3. Zeolite의 첨가에 의해 배양액의 pH나 이온교환능을 안정시키는 것이 가능하고, 양분흡수를 순조롭게 하며, 양분흡수의 증가를 촉진하고 생육촉진도 기대할 수 있었다. 이상의 결과는 인공 zeolite를 암면배지내에 첨가하므로서 이온 보유능, 흡착능을 갖게하여 배지내의 생육환경이 안정되고 암면배지는 인공 zeolite 첨가로 배지의 CEC를 대폭적으로 개선시키는 효과가 컸다.

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Sintering and Electrical Properties of Mn-doped ZnO-$TeO_2$ Ceramics

  • Hong, Youn-Woo;Baek, Seung-Kyoung;Hwang, Hyun-Suk;Shin, Hyo-Soon;Yeo, Dong-Hun;Kim, Jong-Hee
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.49-49
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    • 2008
  • ZnO-based varistors have been widely used for voltage stabilization or transient surge suppression in electric power systems and electronic circuits. Recently, It has reported that the varistor behavior with nonlinear coefficient of 6~17 in Mn-doped ZnO. In this study we have chosen the composition of ZnO-$TeO_2-Mn_3O_4$ (ZTM) system to the purpose of whether varistor behavior appeared in doped ZnO by the solid state sintering or not. We investigated the sintering and electric properties of 0.5~3.0 at% Mn doped ZnO-1.0 at% $TeO_2$ system. Electrical properties, such as current-voltage (I-V), capacitance-voltage (C-V), and impedance spectroscopy were conducted. $TeO_2$ itself melts at $732^{\circ}C$ in air but forms the $ZnTeO_3$ phase with ZnO as increasing temperature and therefore retards the densification of ZnO to $1000^{\circ}C$. The average grain size of sintered samples was at about $3{\mu}m$ and decreased with increasing Mn contents. It was found that a good varistor characteristics were developed in ZTM system sintered at $1100^{\circ}C$ (nonlinear coefficient $\alpha$ ~ 60). The results of C-V characteristics such as barrier height ($\Theta$), donor density ($N_d$), depletion layer (W), and interface state density ($N_t$) in ZTM ceramics were $4\times10^{17}cm^{-3}$, 0.7 V, 40 nm, and $1.6\times10^{12}cm^{-2}$, respectively. It will be discussed about the stability and homogeneity of grain boundaries using distribution parameter ($\alpha$) simulated with the Z(T)"-logf plots in ZTM system.

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Clinical Outcomes after Percutaneous Vertebroplasty for Pathologic Compression Fractures in Osteolytic Metastatic Spinal Disease

  • Lim, Bong-Suk;Chang, Ung-Kyu;Youn, Sang-Min
    • Journal of Korean Neurosurgical Society
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    • 제45권6호
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    • pp.369-374
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    • 2009
  • Objective : Percutaneous vertebroplasty (VP) can provide immediate stabilization in pathologic fractures of spinal tumors. However, long term follow-up data in cases of pathologic fractures are lacking. The authors report follow-up results of VP in 185 pathologic fractures of 102 spinal tumor patients. Methods : Percutaneous VP was performed at 185 vertebral bodies of 102 patients from 2001 to 2007. Retrospective analysis was done with medical records and radiological data. The change of visual analogue score (VAS), vertebral body (VB) height and kyphotic angle were measured preoperatively and on postoperative one day and at 3, 6, and 12 months. Results : The patients were composed of metastatic spine tumors (81%) and multiple myeloma (19%). Involved spinal segments were between T6 and L5. Mean follow-up period was 12.2 months. VAS for back pain was 8.24 preoperatively, 3.59 (postoperative one day), 4.08 (three months) and 5.22 (one year). VB compression ratio changed from 21.33% preoperatively to 13.82% (postoperative one day), 14.36% (three month), and 16.04% (one year). Kyphotic angle changed from $15.35^{\circ}$ preoperatively to $12.03^{\circ}$ (postoperative one day), $13.64^{\circ}$ (three month), and $15.61^{\circ}$ (one year). Conclusion : Immediate pain relief was definite after VP in pathologic compression fracture of osteolytic spinal disease. Although VAS was slightly increased on one year follow-up, VP effect was maintained without significant change. These results indicate that VP could be a safe and effective procedure as a palliative treatment of the spinal tumor patients.

인간간섭에 따른 변산반도 사빈해안의 지형변화 (The Geomorphic Changes of Sand-Beach Coasts by Human Impact in Byeonsan Peninsula, Southwest Korea)

  • 최훈;이민부
    • 한국지형학회지
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    • 제19권3호
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    • pp.83-96
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    • 2012
  • 변산반도 사빈은 포켓비치로서 지형발달 양상에 따라 만입형 사주성 사빈해안과 파식대성 사빈해안으로 분류된다. 두 유형 모두에서 후빙기 해진 극상기에 퇴적되었던 실트 및 점토층이 만입지 내부 표고 약 10m에서 발견되거나 배후구릉에 풍적토가 형성될 만큼 과거에 모래공급이 활발하였다. 이후 자연 상태에서 결핍성 물질수지현상이 일어났으며 최근 새만금방조제 건설로 인해 인근 변산, 고사포 사빈의 인위적인 지형변화가 가속화되고 있다. 이 일대 사빈은 조류유속이 감소되면서 상대적으로 퇴적이 우세해지고 지표 노출 시간이 길어지면서 화학적 풍화도가 높아졌다. 변산 사빈은 동진강을 따라 공급된 세립사가 줄면서 상대적으로 조립화가 우세해지고 사빈침식으로 인해 평행개석곡이 발달하였다. 고사포 사빈은 가력 배수갑문을 통해 부유성 세립사가 늘면서 세립화 경향으로 변모되었다.

PNF Concept중 Scapula and Pelvis의 Symmetrical Reciprocal Pattern이 Hemiplegia환자의 보행속도와 균형감각에 미치는 효과 (Effect of Symmetrical Reciprocal Pattern of Scapula and Pelvis in PNF Concept on the Gait Speed and Balance of thePatients with Hemiplegia)

  • 맹관철;백선영
    • PNF and Movement
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    • 제13권2호
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    • pp.73-80
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    • 2015
  • Purpose: The purpose of this study was to determine the effect of symmetrical-reciprocal pattern of scapula and pelvis exercises using proprioceptive neuromuscular facilitation (PNF) on gait speed and balance in patients with hemiplegia. Methods: Among the adult patients with hemiplegia that were hospitalized at Michuhol Rehabilitation Center after being diagnosed with stroke, 10 that were capable of independent walking for more than five minutes and that understood and cooperated with the therapy and test methods of this research, were selected as subjects. The therapy was implemented based on the concept of PNF, and it was performed on a low mat and a height-adjustable mat, as proscribed by the fundamental procedure for PNF. Symmetrical-reciprocal pattern of scapula and pelvis exercises were applied to the patients in the decubitus position. The therapy scheme included stabilizing reversals, rhythmic stabilization, and a combination of isotonics, rhythmic initiation, and dynamic reversals. To investigate gait speed and body trunk mobility before and after the symmetrical-reciprocal pattern of scapula and pelvis exercises were applied, walking speed for a distance of 10 m was measured and balance was tested based on the Berg-Balance scale test table. The Berg-Balance scale test was performed by one therapist to minimize any error that could occur from the subjective evaluation method used by therapists. Results: Gait speed increased by 8.97 seconds after applying the symmetrical-reciprocal pattern of scapula and pelvis exercises using the concept of PNF, showing a significant difference (p<0.01). However, balance showed no significant difference after the therapy (p>0.14). Conclusion: Exercise therapy that uses the symmetrical-reciprocal pattern of scapula and pelvis with the concept of PNF can be said to be a useful therapeutic technique that can enhance the walking speed of patients with hemiplegia.

Effects of Pilates Reformer Core and Mat Core Exercises on Standing Posture Alignment

  • Sim, Gyeongseop;Kim, Donghoon;Jeon, Hyeseon
    • 한국전문물리치료학회지
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    • 제29권4호
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    • pp.282-288
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    • 2022
  • Background: Pilates exercises are used for body shape correction because they can achieve correct posture alignment through spinal stabilization. Objects: This study aimed to determine whether the use of reformers increases the effectiveness of Pilates core exercises on body alignment in standing. Methods: The study included 30 women without known diagnoses of musculoskeletal and neurological disorders or cancer. Those who had taken more than 10 Pilates lessons were excluded. The participants were randomly assigned to either the reformer exercise group or the mat exercise group, and interventional Pilates exercises were performed for 60 minutes a day, three times a week, for a total of 8 weeks. Ten movements of the reformer and mat Pilates core exercise programs were included. Exbody® 9100 MOMI musculoskeletal analysis equipment (Exbody Inc.) was used to assess the alignment of the standing posture in the frontal plane. Results: As a result of comparing the differences within and between the groups before and after the intervention using the two-way mixed analysis of variance test, height differences in the head, pelvis, left and right, shoulders, scapulas, knees, and ankles in the frontal plane after the intervention were found in both groups. For example, the left-right symmetry of the body alignment in the standing posture was significantly improved within each group (p < 0.05). However, no significant difference was found between the groups (p > 0.05). Conclusion: Both the reformer and mat Pilates core exercises were effective for standing posture alignment, which has clinical significance. If an exercise program is developed based on the analysis of movements necessary for posture improvement and the target muscles to be strengthened, the same effect can be achieved only with mat exercise without using the reformer equipment at the beginner stage.

Monitoring of Moisture and Dimensional Behaviors of Nail-Laminated Timber (NLT)-Concrete Slab Exposed to Outdoor Air

  • HWANG, Sung-Wook;CHUNG, Hyunwoo;LEE, Taekyeong;AHN, Kyung-Sun;PANG, Sung-Jun;BANG, Junsik;Won, Hyo;OH, Jung-Kwon;YEO, Hwanmyeong
    • Journal of the Korean Wood Science and Technology
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    • 제50권5호
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    • pp.301-314
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    • 2022
  • The moisture and dimensional behaviors of a nail-laminated timber (NLT)-concrete slab composed of an NLT-plywood composite and topping concrete are monitored for 385 days. The slab is developed for using as flexural elements such as floors. The humidity control of wood gently introduces significant fluctuations under the ambient relative humidity into the slab, and fluctuations in the relative humidity result in dimensional changes. The equilibrium moisture content of the slab increases from 6.7% to 15.3% during the monitoring period, resulting in a width (radial) strain of 0.58%. The length (longitudinal) strain is negligible, and the height (tangential) strain is excluded from the analysis because of abstruse signal patterns generated. Concrete pouring causes a permanent increase in the width of the NLT-plywood composite. However, the width deforms because the weight of the concrete mixture loosens the nail-laminated structure, not because of the significant amount of moisture in the mixture. The dimensional stabilization effect of the nail-laminated system is demonstrated as the composite strain is lower than the total strain of lumber and plywood, which are elements constituting the nail-laminated structure.

Mobile sand barriers for windblown sand mitigation: Effects of plane layout and included angle

  • Gao, Li;Cheng, Jian-jun;Ding, Bo-song;Lei, Jia;An, Yuan-feng;Ma, Ben-teng
    • Wind and Structures
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    • 제34권3호
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    • pp.275-290
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    • 2022
  • Mobile sand barriers are a new type sand-retaining structure that can be moved and arranged according to the engineering demands of sand control. When only used for sand trapping, mobile sand barriers could be arranged in single row. For the dual purposes of sand trapping and sand stabilization, four rows of mobile sand barriers can be arranged in a staggered form. To reveal the effect of plane layout, the included angle between sand barrier direction and wind direction on the characteristics of flow fields and the sand control laws of mobile sand barriers, numerical computations and wind tunnel tests were conducted. The results showed that inflows deflected after passing through staggered arrangement sand barriers due to changes in included angle, and the sand barrier combination exerted successive wind resistance and group blocking effects. An analysis of wind resistance efficiency revealed that the effective protection length of staggered arrangement sand barriers approximately ranged from the sand barrier to 10H on the leeward side (H is sand barrier height), and that the effective protection length of single row sand barriers roughly ranged from 1H on the windward side to 20H on the leeward side. The distribution of sand deposit indicated that the sand interception increased with increasing included angle in staggered arrangement. The wind-breaking and sand-trapping effects were optimal when included angle between sand barrier direction and wind direction is 60°-90°.

사막화방지(沙漠化防止) 및 방사기술개발(防沙技術開發)에 관한 연구(硏究)(IV) - 중국(中國)의 사구고정(沙丘固定) 및 방사공법분석(防沙工法分析) - (Studies on the Desertification Combating and Sand Industry Development(IV) - Technology Development for Sanddune Fixation and Sandy Land Conservation in China -)

  • 우보명;이경준;최형태;이상호;박주원;왕례선;장극빈;손보평
    • 한국산림과학회지
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    • 제90권3호
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    • pp.277-294
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    • 2001
  • 이 연구에서는 지난 3년간 북경임업대학교와 공동연구과제로 중국의 사막화방지 및 방사기술개발을 위한 연구의 일환으로, 특히 중국의 사구고정 및 방사공법을 조사 분석 평가하고자 수행하였다. 사구의 주요 형태에는 관목총사구, 사랑사구, 지상사구, 봉소상사구, 격자상사구, 양설상사구, 초생달사구, 포물선상사구, 초생달사연사구, 초생달사롱, 피라미드상사구, 복합형초생달형사구, 복합형종사롱사구, 돔상사구, 불규칙한 사구 사지 등 매우 다양하다. 이들 사구의 분포비율은 높이 5m이하 13%, 6~10m 17%, 11~25m 18%, 26~50m 14%, 51~100m 28%, 100m 이상 10% 등이다. 중국 건조지역에서 사구의 이동방향은 주로 주풍방향에 따르나 지역 지형 사구의 크기 및 형태 등에 따라서 이동사구형태에 차이가 많다. 사막화지에서 주요 비사방지기술(방사공법)은 생물 생태적 방사공법(식물피복방법 식재에 의한 방법), 물리적 방사공법, 화학적 방사공법 등으로 구분할 수 있는데, 생물 생태적 방사공법에는 초생법(봉사육초(封沙育草)), 관목 초생고사법(草生固沙法), 사구간 방사림대, 기간방사림대, 경지방풍림대조성 등이 있고, 물리적 방사공법에는 고방사원(高防沙垣) 및 저방사원 조성, 방사제방, 석력점토피복법 등이 있으며, 화학적 방사공법에는 고화제뿜어붙이기, 유사개량화학역제혼용법 등이 효과적인 것으로 분석되었다. 그 밖에도 관개 침사공법, 비사포착수로 구방사공법(溝防沙工法) 등이 효과적인 것으로 판단된다.

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승마 속보 시 등자 길이에 따른 체간기울기와 양측 하지의 협응성 비교분석 : 비대칭 지수 및 전체이동지수 알고리즘 개발 (Analysis of the Coordination of the Trunk Tilting Angle and Bilateral Lower Limbs According to the Stirrups Length during Trot in Equestrian: Asymmetric Index Development of Overall Movement Index Algorithm)

  • 현승현;류재청
    • 한국운동역학회지
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    • 제25권1호
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    • pp.131-140
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    • 2015
  • Purpose : The purpose of this study was to analyze the coordination of the trunk tilting angle and bilateral lower limbs according to the stirrups length during trot in equestrian. Methods : Participants selected as subject were consisted of adult male(n=7, mean age: $45.00{\pm}3.78yrs$, mean height: $172.50{\pm}2.44cm$, mean body mass: $76.95{\pm}4.40kg$, mean, mean leg length: $97.30{\pm}2.60cm$). They were divided into 3-types of stirrups lengths(67 cm, 72 cm, 77 cm) during trot. The variables analyzed were consisted of the trunk front-rear angle, lower limb joint(Right Left hip, knee, ankle), overall movement index(OMI) of the lower limbs(thigh, shank, foot) and asymmetry index(AI%) during trot. Results : The average angle in hip and knee joint showed more extended posture according to the increase of stirrups lengths and ankle angle showed more plantarflexion posture according to increase of stirrups length during 1 stride in trot. Also, average angle showed more extended posture in right hip and ankle joint than that of left. The angle of knee joint didn't show significant difference statistically between right and left. Also asymmetric index in average angle of hip, knee and ankle joint didn't show significant difference statistically in between lower limbs, but hip joint showed higher asymmetric index in stirrup length of 77 cm and ankle joint showed higher asymmetric index in stirrup length of 67 cm than that of the others respectively. The FR angle in trunk of horse-rider showed relative backward leaning motions at stirrup length of 67 cm and 77 cm than that of stirrup length of 72 cm during stance and swing phase. OMI in thigh, shank, and foot limbs didn't show significant difference statistically according to the stirrups length of right and left lower limbs, but left lower limbs showed higher index than that of right lower limb. Stirrup length of 72 cm in shank and foot limbs showed higher index than that of stirrup length of 67 cm and 77 cm. But stirrup length of 72 cm showed higher asymmetric index than that of stirrups length of 67 cm and 77 cm. Conclusions : When considering the above, 72 cm(ratio of lower limb 74.04%) stirrup lengths could be useful in posture correction and stabilization than 67cm(ratio of lower limb 68.69%) and 77 cm(ratio of lower limb 79.18%) stirrup lengths during trot in horse back riding.