• Title/Summary/Keyword: Pressure resistance

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Changes of Brain Natriuretic Peptide Levels according to Right Ventricular HemodynaMics after a Pulmonary Resection (폐절제술 후 우심실의 혈역학적 변화에 따른 BNP의 변화)

  • Na, Myung-Hoon;Han, Jong-Hee;Kang, Min-Woong;Yu, Jae-Hyeon;Lim, Seung-Pyung;Lee, Young;Choi, Jae-Sung;Yoon, Seok-Hwa;Choi, Si-Wan
    • Journal of Chest Surgery
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    • v.40 no.9
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    • pp.593-599
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    • 2007
  • Background: The correlation between levels of brain natriuretic peptide (BNP) and the effect of pulmonary resection on the right ventricle of the heart is not yet widely known. This study aims to assess the relationship between the change in hemodynamic values of the right ventricle and increased BNP levels as a compensatory mechanism for right heart failure following pulmonary resection and to evaluate the role of the BNP level as an index of right heart failure after pulmonary resection. Material and Method: In 12 non small cell lung cancer patients that had received a lobectomy or pnemonectomy, the level of NT-proBNP was measured using the immunochemical method (Elecsys $1010^{(R)}$, Roche, Germany) which was compared with hemodynamic variables determined through the use of a Swan-Garz catheter prior to and following the surgery. Echocardiography was performed prior to and following the surgery, to measure changes in right ventricular and left ventricular pressures. For statistical analysis, the Wilcoxon rank sum test and linear regression analysis were conducted using SPSSWIN (version, 11.5). Result: The level of postoperative NT-proBNP (pg/mL) significantly increased for 6 hours, then for 1 day, 2 days, 3 days and 7 days after the surgery (p=0.003, 0.002, 0.002, 0.006, 0.004). Of the hemodynamic variables measured using the Swan-Ganz catheter, the mean pulmonary artery pressure after the surgery when compared with the pressure prior to surgery significantly increased at 0 hours, 6 hours, then 1 day, 2 days, and 3 days after the surgery (p=0.002, 0,002, 0.006, 0.007, 0.008). The right ventricular pressure significantly increased at 0 hours, 6 hours, then 1 day, and 3 days after the surgery (p=0.000, 0.009, 0.044, 0.032). The pulmonary vascular resistance index [pulmonary vascular resistance index=(mean pulmonary artery pressure-mean pulmonary capillary wedge pressure)/cardiac output index] significantly increased at 6 hours, then 2 days after the surgery (p=0.008, 0.028). When a regression analysis was conducted for changes in the mean pulmonary artery pressure and NT-proBNP levels after the surgery, significance was evident after 6 hours (r=0.602, p=0.038) and there was no significance thereafter. Echocardiography displayed no significant changes after the surgery. Conclusion: There was a significant correlation between changes in the mean pulmonary artery pressure and the NT-proBNP level 6 hours after a pulmonary resection. Therefore, it can be concluded that changes in NT-proBNP level after a pulmonary resection can serve as an index that reflects early hemodynamic changes in the right ventricle after a pulmonary resection.

Soil Improvement using Vertical Natural Fiber Drains (연직천연섬유배수재를 이용한 연약지반 개량)

  • Kim, Ju-Hyong;Cho, Sam-Deok
    • Journal of the Korean Geosynthetics Society
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    • v.7 no.4
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    • pp.37-45
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    • 2008
  • A pilot test using environmentally friendly drains, was carried out to evaluate their applicability potential in the field. The pilot test site was divided into 5 different areas, with several combinations of vertical and horizontal drains installed for evaluation. Conventional natural fiber drains (FDB), new developed straw drain board (SDB) and plastic drain board (PDB) were used as vertical drains, while sand and fiber mats were used as horizontal drains. Surface settlement rates and excess pore pressure generation/dissipation tendency of PDB and FDB are almost identical except those of SDB. Cone tip resistance obtained from cone penetration test measured at the end of 1st consolidation stage for upper soft layer definitely increased irrespective of types of vertical drains. The monitoring and site investigation test data obtained at the pilot test site prove the vertical natural fiber drains can be used as substitutes of conventional plastic and sand material.

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A Study on Products Analysis of the Domestic and Overseas Cycling Wears (시판 국내외 사이클 웨어의 제품 분석)

  • Park, Hyunjeong;Do, Wolhee
    • Fashion & Textile Research Journal
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    • v.22 no.3
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    • pp.368-377
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    • 2020
  • This study provided basic data to develop functional and fitness cycling wear for cyclists. We analyzed the domestic and overseas cycling wear brand patterns for tops and tights as well as compared pads attached to tights. The results were as follows. The tops of the cycling wear were designed with cutting lines in the lateral or yoke in the back to reflect cycling posture. It is necessary to study if there is a difference in the air resistance or fitness of the athlete. The sleeve hem band affected by arm movement during cycling, proper sewing and band pressure are also important. The tights have a brand that does not insert a band in front of the waist in consideration of the cyclist's breathing. It should take into account methods of constructing a proper garment pressure that does not interfere with cycling. Analyzing the cycling pad indicated that the three-dimensional shape and size of the pad show many differences for each brand, indicating a difference in cycling movement suitability. In addition, many of the cutting lines should account for the productive aspects because of the high consumption of the fabric in order to design a pattern considering the cycling posture.

A study on the average wind load characteristics and wind-induced responses of a super-large straight-cone steel cooling tower

  • Ke, S.T.;Du, L.Y.;Ge, Y.J.;Zhao, L.;Tamura, Y.
    • Wind and Structures
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    • v.25 no.5
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    • pp.433-457
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    • 2017
  • As a novel typical wind-sensitive structure, the wind load and wind-induced structural behaviors of super-large straight-cone cooling towers are in an urgent need to be addressed and studied. A super large straight-cone steel cooling tower (189 m high, the highest in Asia) that is under construction in Shanxi Power Plant in China was taken as an example, for which four finite element models corresponding to four structural types: the main drum; main drum + stiffening rings; main drum + stiffening rings + auxiliary rings (auxiliary rings are hinged with the main drum and the ground respectively); and main drum + stiffening rings + auxiliary rings (auxiliary rings are fixed onto the main drum and the ground respectively), were established to compare and analyze the dynamic properties and force transferring paths of different models. After that, CFD method was used to conduct numerical simulation of flow field and mean wind load around the cooling tower. Through field measurements and wind tunnel tests at home and abroad, the reliability of using CFD method for numerical simulation was confirmed. On the basis of this, the surface flow and trail characteristics of the tower at different heights were derived and the wind pressure distribution curves for the internal and external surfaces at different heights of the tower were studied. Finally, based on the calculation results of wind-induced responses of the four models, the effects of stiffening rings, auxiliary rings, and different connecting modes on the dynamic properties and wind-induced responses of the tower structure were derived and analyzed; meanwhile, the effect mechanism of internal suction on such kind of cooling tower was discussed. The study results could provide references to the structure selection and wind resistance design of such type of steel cooling towers.

The passive stretching, massage, and muscle energy technique effects on range of motion, strength, and pressure pain threshold in musculoskeletal neck pain of young adults

  • Jeong, Hye Mi;Shim, Jae-Hoon;Suh, Hye Rim
    • Physical Therapy Rehabilitation Science
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    • v.6 no.4
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    • pp.196-201
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    • 2017
  • Objective: Musculoskeletal neck pain have many symptoms which include decreased range of motion (ROM) and muscle strength, and increased pain. However, the management methods are controversial. The purpose of this study was to examine the effects of three interventions on ROM, strength, and pressure pain threshold (PPT) with musculoskeletal neck pain. Design: Pretest-posttest design. Methods: Thirty subjects participated in this experiment. They were randomly assigned to thefollowing groups: passive stretching (PS) group (n=10), massage (MASS) group (n=10), and muscle energy technique (MET) group (n=10). The treatment were applied bilaterally on the upper trapezius. The PS was applied 3 times for 30 seconds each time. The MASS was applied using two different techniques for 2 minutes per technique. For MET, the subjects performed 2 sets of 3 repetitions of isometric resistance exercise that was maintained for 10 seconds, followed by 10 seconds of rest. ROM, strength, and PPT parameters were measured after intervention. Results: In the MASS group, there was a significant improvement in all outcomes except for muscle strength (p<0.05). In the MET group, ROM and strength significantly improved compared to the pre-treatment results (p<0.05). As result of measuring the amount of change in each group, there was a significant difference in ROM (flexion) in the PS group compared with the MASS and MET group, a significant difference in strength in the MET group compared with the PS and MASS groups, and a significant difference in PPT in the MASS groups compared with the PS and MET groups (p<0.05). Conclusions: This study showed that PS, MASS, and MET are effective methods for improving ROM, strength, and PPT for musculoskeletal neck pain. Therefore, various therapeutic interventions for improving ROM, strength, and pain are suggested.

Settlement Reduction Effect of the Geogrid Reinforced Stone Column System (고강도 지오그리드로 보강된 Stone Column 공법의 침하감소효과)

  • Park, Sis-Am;Cho, Sung-Han;Yoo, Chung-Sik;Lee, Dae-Young
    • Journal of the Korean Geosynthetics Society
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    • v.5 no.1
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    • pp.15-23
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    • 2006
  • Sand Compaction Pile and Stone Column method have been used in widely during several decades as a technique to reinforce soft soils and increasing ultimate bearing capacity, accelerate consolidation settlement of the foundation ground. Stone column method, making a compaction pile using crushed stone, is a soft ground improvement method. However, stone column method is difficult to apply to the ground which is not mobilized enough lateral confine pressure because no bulging failure resistance. Hence, in present study, development the geogrid reinforced stone column system for settlement reduction and wide range of application of stone columns. To develop this system, triaxial compression tests were conducted for evaluation which is about behavior characteristics of stone column on replacement rate and confine pressure. Then, 3-dimensional numerical analysis were evaluated for application of the GRSC (geogrid reinforced stone column) system as evaluate behavior characteristics and settlement reduction effect of stone column reinforced by geogrid on types and reinforcing depth change of geogrid.

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An Experimental Test for Air-tightness Performance Evaluation of Cracked Concrete Vacuum Tube Structures (콘크리트 진공튜브의 균열 발생에 따른 기밀성능 평가 실험)

  • Park, Joonam;Park, Hyeong-Jun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.38 no.3
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    • pp.377-385
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    • 2018
  • Super-speed vacuum tube system, where the air resistance is minimized to obtain high speed of the vehicle, is considered to be a viable alternative transportation system. Air-tightness is one of the most important design requirements of the system, because the internal pressure of the system needs to be maintained significantly lower than the atmospheric pressure. This study performed an experimental test, where a series of concrete tube specimens were applied by external loads to induce cracks and the effective air-permeability of the cracked tube structures were measured. The test results indicates that the information on the length and the width of the load-induced cracks are not enough to anticipate the system air-tightness, whereas the load-induced displacement has higher correlation with the systems air-tightness. Based on these results, a direction of future research for effect of the load-induced cracks on the system air-tightness is suggested.

Effect of Air Flow Change on Voice Parameters : In Vivo Canine Laryngeal Model (생체 발성모형에서 발성시 공기양의 변화가 음성 지표에 미치는 영향)

  • 최홍식
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.5 no.1
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    • pp.5-10
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    • 1994
  • In vivo canine model was made in two mongrel dogs under the general Ⅰ-Ⅴ anesthesia. A vertical skin incision was made on the neck, the larynx and the trachea were dissected. Two tracheal openings were made : lower one for the insertion of the anesthesia tube and upper one for the delivery of air to the larynx to induce phonation. External branch of the superior laryngeal nerves and recurrent laryngeal nerves bilaterally were identified and stimulated electrically constantly. Subglottic pressure. fundamental frequency, intensity, and open quotient were measured when the air flow rate was varying low, medium and high. Glottic resistence was calculated. As the air flow rate was increased, the subglottic pressure and the sound intensity were increased. However, glottic resistance was decreased as the air flow was increased. In falsetto register, fundamenatal frequency was increased with the increment of air flow, but in modal register fundamental frequency was not increased statistically significant Open quotient by the electroglottography was increased according to the increment of airflow.

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Fabrication of a Film Coated with Conducting Polymer Using One Atmospheric Pressure Plasma (대기압 플라즈마를 이용한 전도성 고분자 코팅 필름 제조)

  • Jung, Jin-Suk;Yang, In-Young;Myung, Sung-Woon;Choi, Ho-Suk;Kim, Jong-Hoon
    • Polymer(Korea)
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    • v.31 no.4
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    • pp.308-314
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    • 2007
  • A composite film of polyurethane(PU)-graft-poly(acrylic acid) (PAAc)/polyaniline (PU-g-AAc/PANI) was successfully fabricated for the purpose of adding conductivity on the surface of a general purpose polymer and improving adhesive property between the general purpose polymer and conducting polymer layer. The results from ATR-FTIR and XPS analyses also supported the successful synthesis of the composite film by showing characteristic peaks for every step. A low surface resistivity of $2{\times}10^3\;ohm/sq$ proved the surface conductivity of synthesized PU-g-AAc/PANI film and the surface resistance decreased with increasing the amount of grafted AAc, which acted as a dopant for PANI film.

Fabrication of oxide semiconductor thin film gas sensor array (산화물 반도체 박막 가스센서 어레이의 제조)

  • 이규정;김석환;허창우
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.4 no.3
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    • pp.705-711
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    • 2000
  • A thin film oxide semiconductor micro gas sensor array which shows only 60 mW of power consumption at an operating temperature of $300^{\circ}C$ has been fabricated using microfabrication and micromachining techniques. Excellent thermal insulation of the membrane is achieved by the use of a double-layer structure of $0.1\mum\; thick\; Si_3N_4 \;and\; 1 \mum$ thick phosphosilicate glass (PSG) prepared by low-pressure chemical-vapor deposition (LPCVD) and atmospheric-pressure chemical-vapor deposition (APCVD), respectively. The sensor array consists of such thin film oxide semiconductor sensing materials as 1 wt.% Pd-doped $SnO_2,\; 6 wt.% A1_2O_3-doped\; ZnO,\; WO_3$/ and ZnO. Baseline resistances of the four sensing materials were found to be stable after the aging for three days at $300^{\circ}C$. The thin film oxide semiconductor micro gas sensor array exhibited resistance changes usable for subsequent data processing upon exposure to various gases and the sensitivity strongly depended on the sensing layer materials.

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