• 제목/요약/키워드: stretch characteristics

검색결과 119건 처리시간 0.021초

충돌제트 버너에서 합성가스($H_2/CO$) 공기 예혼합 화염의 열전달 특성에 관한 실험적 연구 - Part 1 : 스트레치된 부상 화염 (An Experimental Study on Heat Transfer Characteristics of Synthetic Gas($H_2/CO$)Air Premixed Flames in an Impinging Jet Burner - Part 1 : Stretched Lift-off Flames)

  • 강기중;조준익;이기만
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2011년도 제36회 춘계학술대회논문집
    • /
    • pp.453-456
    • /
    • 2011
  • 합성가스를 이용한 충돌제트 버너에서 신장된 예혼합 화염의 열전달 특성에 관한 실험적 연구를 수행하였다. 본 연구에서는 석탄을 가스화하는 과정에서 추출되는 수소와 일산화탄소를 혼합한 합성가스를 연료로 사용하였다. 정체점에서의 열유속은 전체 신장율이 증가함에 따라 증가하다 다시 감소하는 것이 관찰되었다. 또한 정체점에서의 열유속이 노즐로부터 충돌판까지 거리가 증가함에 따라 증가하는 것을 확인하였다. 본 연구는 석탄에서 발생하는 부생가스의 주성분인 수소와 일산화탄소를 실용화하는 연구 중 기초 연구이다.

  • PDF

석문일월무예 음양보법의 숙련성에 따른 보행 패턴의 하지 운동학 및 운동역학적 특성 (A Study of Motor Expertise about Kinematic and Kinetic Characteristics of Lower Extremity in the Seokmun Ilwol Martial Art Yin-yang Bo Gait Pattern)

  • 박복희;김기형
    • 한국운동역학회지
    • /
    • 제24권3호
    • /
    • pp.239-248
    • /
    • 2014
  • The purpose of this study was to quantify kinematic and kinetic characteristics of Yin-yang Bo gait according to their motor expertise, one of the Seokmun Ilwol martial art gait patterns. Yin-yang Bo gait pattern shows initial forefoot contact instead of heel contact, and increased time of stance phase time, internal-external rotation of ankle-knee-hip joints and pelvic. It aims to produce and store the more energy through continuous homeostasis of center of gravity (COG) and performance of stretch-shortening cycle. Some of these characteristics also were similar to the gait modification strategies for reducing knee adduction moment such as toe-out progression, medial thrust, internal rotation of hip joint. To identify the characteristics, four factors of expert Yin-yang Bo gait performance group were compared to that of none expert group; 1) angles of COG displacement and rotation 2) distal joint pre-rotation in internal-external rotation of ankle-knee-hip joints and pelvic, 3) invariability pelvic potential and pelvic segment total energy 4) knee abduction moment. Six healthy(three male) subjects participated in the experiment to perform Yin-yang gait pattern. Three-dimensional and force plate data were collected. Kinematic and kinetic data were compared between two groups using t-tests. Results showed that 1) the peak point of COG internal rotation angle was reduced in expert group, 2) kneeexternal and hip joint -internal and pelvic rotation angle peak frames were more near points in expert group.

음향 가진 된 프로판 확산 화염의 부상 거동에 관한 실험적 연구 (Experimental Study on the Lift-off Behavior of Tone-excited Propane Jet Diffusion flames)

  • 김승곤;박정;김태권;이기만
    • 한국연소학회:학술대회논문집
    • /
    • 한국연소학회 제26회 KOSCO SYMPOSIUM 논문집
    • /
    • pp.65-73
    • /
    • 2003
  • An experimental study on flame lift-off characteristics of propane jet flame highly diluted with nitrogen has been conducted introducing acoustic forcing with a tube resonant frequency. A flame stability curve is attained according to forcing strength and nozzle exit velocity for $N_2$ diluted flames. Flame lift-off behavior with forcing strength and nozzle exit velocity is globally categorized into three; a well premixed behavior caused by a collapsible mixing for large forcing strength, a coexistent behavior of well-premixed and edge flames interacting with well-organized inner fuel vortices for moderate forcing strengths, and edge flame behavior for small forcing strengths. Special focus is concentrated on the coexistent behavior of the flame base in lifted flame since this may give a hint to a possibility which the flame base behaves like a well-mixed premixed flame in highly turbulent lifted flames. It is also shown that the acoustic forcing to self-pulsating laminar lifted flame affects flame lift-off behavior considerably which is closely related to downstream flow velocity, mixture strength, effective fuel Lewis number, and flame stretch.

  • PDF

만성통증이 있는 근골격계 환자의 대처와 무력감 (Coping and Powerlessnessof Musculoskeletal Patients with Chronic Pain)

  • 최귀윤
    • 대한간호
    • /
    • 제36권4호
    • /
    • pp.88-99
    • /
    • 1997
  • Applying effective coping strategies and reducing powerlessness for the chronic pain adjustment of musculoskeletal patients were researched for basic data in the development of nursing intervention. The subjects were 99 musculoskeletal patients with chronic pain. Data was gathered with direct interview using a questionnaire. With the SAS tool. data were analyzed for percentage. Pearson correlation. t-test. and ANOVA according to characteristics of variables. Internal consistency(alpha) coefficients were .91 for coping scales and .71 for powerlessness scales. The results are as follows: 1. Pain duration was mainly 6 - 12 months(52. 5%). 2. Primary pain site was mainly lower limbs(58.6%) and pain severity was a moderate level. 3. The preference of coping strategies was decreased in the order named in resting. seeking social support. exercise or stretch. guarding. and asking for assistance. 4. The longer pain duration. the more the coping strategies of asking assistance used. This was stastically significant(F=3. 35. p<.05). 5. The group with the experience of hospital admission was more powerless than the group without that(F=3. as. p<.01). 6. Pain severity and powerlessness were significantly positively correlated(r=.444. p<.001). Coping strategy applying and powerlessness were significantly negatively correlated(r=-. 288. p<.01). In consequence. the nurse should playa role as the supporter of patient's maximal usage of his resources in pain relief. adjustment, and control. The nurses should also develop for the nursing intervention of physical therapy and educational programs.

  • PDF

압출 블로우 성형에서 성형조건에 따른 성형특성 (Blow Characteristics in Extrusion Blow Molding for Operational Conditions)

  • 전재후;배유리;류민영
    • 소성∙가공
    • /
    • 제14권3호
    • /
    • pp.233-238
    • /
    • 2005
  • Blow molding is divided into three categories, injection stretch blow molding, injection blow molding, and extrusion or direct blow molding. Extrusion blow molding has been studied experimentally to characterize the blowing behavior of parison. Blow conditions such as blowing temperature and cooling time were the experimental variables in this blowing experiment. Wall thickness of the lower part of blow molded sample was thicker than that of the upper part because of the sagging of parison during extrusion process. As temperature increases the wall thickness and the weight of blow molded sample decreased. No thickness variations in the blowing sample were observed according to the cooling time. The lower part of the sample showed high degree of crystallinity compare with the upper part of the sample. Thus the lower part of the sample was strong mechanically and structurally. It was recognized that the uniform wall thickness could not be obtained by only controlling the operational conditions. Parison variator should be introduced to get uniform wall thickness of parison and subsequently produce uniform wall thickness of blow molded product.

테니스 양손 백핸드 스트로크 방법에 따른 어깨와 힙의 회전운동 변화 (Change in Rotational Motion of the Shoulder and Hip According to the Method Used for a 2-Handed Backhand Stroke in Tennis)

  • 강상학
    • 한국운동역학회지
    • /
    • 제21권1호
    • /
    • pp.39-46
    • /
    • 2011
  • The purpose of this study was to examine differences between players who bend the left elbow and those who stretch it during the forward swing from BST to BC in a 2-handed backhand stroke among outstanding high school tennis players, and to assess the detailed 3D rotational kinematic characteristics of the shoulder and the hip. Statistically significant differences were observed between groups in the longitudinal axis rotation angle of the shoulder and the angle between the shoulder and the arm at BST, and in the side to side movement of the shoulder, the up and down movement of the hip, the side tilt angular velocity of the shoulder, the side tilt angular velocity of the hip, and the front tilt angular velocity of the hip at BC. The difference in the longitudinal axis rotation angle of the shoulder between the 2 groups suggests a difference in the flexibility of the joint in the shoulder arm racquet system. The longitudinal axis rotation angular velocity of the shoulder reached its peak at 75 % of the duration of the analyzed segment and then decreased little by little until BC. This time is considered the stage for increasing the angular velocity of the upper arm, the forearm, the hand and then the racquet, which are more distal segments than the shoulder.

경직의 정량 평가를 위한 진자실험의 변수분석 (A Study on the Parameter Analysis for the Quantitative Evaluation of Spasticity Implementing Pendulum Test)

  • 임현균;이영신;조강희;채진목;김봉옥
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2000년도 춘계학술대회논문집A
    • /
    • pp.268-273
    • /
    • 2000
  • Velocity-dependent increase in tonic stretch reflexes is one of the prominent characteristics of spasticity. It is very important to evaluate spasticity objectively and quantitatively before and after treatment for physicians. An accurate quantitative biomechanical evaluation for the spasticity which is caused by the disorder of central nervous system is made in this study. A sudden leg dropper which is designed to generate objective testing environment at every trial gives very effective environment for the test. Kinematic data are archived by the 3-dimensional motion analysis system($Elite^{(R)}$, B.T.S., Italy). Kinematic data are angle and angular velocity of lower limb joints, and length and lengthening velocity of lower limb muscle. A program is also developed to analyze the kinematic data of lower limb, contraction and relaxation length of muscles, and dynamic EMG data at the same tim. To evaluate spasticity quantitatively, total 31 parameters extracted from goniogram, EMG and muscle model are analyzed. Statistical analysis are made for bilateral correlations for all parameters. The described instrumentation and parameters to make quantitative and objective evaluation of spasticity shows good results.

  • PDF

목 안정화 운동이 경추성두통 환자의 근육특성과 근활성도 및 자세에 미치는 영향 (Effects of Neck Stabilizing Exercise on Muscle Characteristics, Muscle Activity and Posture in Patients with Cervicogenic Headache)

  • 박승규;윤종혁
    • 대한통합의학회지
    • /
    • 제7권4호
    • /
    • pp.301-309
    • /
    • 2019
  • Purpose : The purpose of this study was to provide an effective method of exercise therapy for patients with cervicogenic headache. Methods : The subjects were divided into the following two groups according to the intervention received: cervical stretch exercise (n=15, control group) cervix-stabilizing exercise (n=15, experimental group) tone (Hz) and stiffness (N/m) of the suboccipital and upper trapezius muscles were measured. T1 slope angle and neck tilt angle were measured. After the exercise program intervention, a greater amount of change in muscle tone and stiffness of suboccipital and upper trapezius muscles was found in the experimental group, as compared to the control group. Greater amount of change in posture was found in the experimental group, as compared to the control group (p<0.05). Results : After the exercise program intervention, a greater amount of change in muscle tone and stiffness of suboccipital and upper trapezius muscles was found in the experimental group, as compared to the control group. Greater amount of change in posture was found in the experimental group, as compared to the control group (p<0.05). Conclusion : The neck-stabilizing exercise were shown to be effective in decreasing the tone of the cervical muscles by stabilizing the cervical bone and improving muscle activity, and in improving the posture by decreasing muscle tone and stiffness.

영화(映畵) "벨벳 골드마인(Velvet Goldmine)"에 나타난 글램 스타일(Glam Style) (The Glam Style Expressed in the Movie "Velvet Goldmine")

  • 김은아;염혜정
    • 패션비즈니스
    • /
    • 제5권1호
    • /
    • pp.73-85
    • /
    • 2001
  • The purpose of this study is to understand what the Glam Style is, focus on the movie "Velvet Goldmine". The Glam Style is refered early 1970s Glam rockers' costume, typified by silver lurex, corksoled platform, men in make-up, personified, for example, by David Bowie, Marc Bolan, New York Dolls, Roxy Music and Iggy Pop. To approach the Glam Style comprehensively, I have divided the formative background of Glam Style into the improvement technology, the advent of the young generation and the diffusion of mass media, the rock music fever and influence on Pop art. Following is the result of analyzing of the character in the movie. First, Brian Slade has the flamboyant transsexual image by skin-tight space suit, glitter pants, lurex, satin and sequined stretch fabrics, vivid color, gauze make-up, feather boa. Second, Curt Wild expresses the outrageous sexual image by black leather jacket, emphasized black eyes make-up. Third, Mandy Slade appears the exaggerated and frivolous image by gold leopard patterned one piece, fur coat, ornamented with beads, tropical make-up, spangles and the costume jewelry. Forth, Auther Stuart has the complex image by black leather jacket, velvet jacket, skin-tight bold shirt, glitter pants, glitter make-up, silk scarf, cherry-red sunglasses. The characteristics meaning of Glam Style implied in this formative characteristic could be presented as the experimental expression of androgynous, the hordes of outrageous alien and kitsch parody.

  • PDF

질감 제시 장치를 이용한 촉감인지 특성 연구 (Study of Human Tactile Sensing Characteristics Using Tactile Display System)

  • 손승우;경기욱;양기훈;권동수
    • 제어로봇시스템학회논문지
    • /
    • 제11권5호
    • /
    • pp.451-456
    • /
    • 2005
  • This paper describes three kinds of experiments and analysis of their results related to human tactile sensitivity using an integrated tactile display system. The device can provide vibration, normal pressure and lateral slip/stretch which are important physical quantities to sense texture. We have tried to find out the efficient method of stimulating, limitation of surface discrimination by kinesthetic farce feedback and the effectiveness of the combination of kinesthetic force and tactile feedback. Seven kinds of different stimulating methods were carried out and they are single or combination of the kinesthetic force, normal static pressure, vibration, active/passive shear and moving wave. Both prototype specimen and stimulus using tactile display were provided to all examinees and they were allowed to answer the most similar sample. The experimental results show that static pressure is proper stimulus for the display of micro shape of the surface and vibrating stimulus is more effective for the display of fine surface. And the sensitivities of active touch and passive touch are compared. Since kinesthetic force feedback is appropriate to display shape and stiffness of an object, but roughness display has a limitation of resolution, the concurrent providing methods of kinesthetic and tactile feedback are applied to simulate physical properties during touching an object.