• Title/Summary/Keyword: angle standard

Search Result 930, Processing Time 0.03 seconds

Influence of Detailed Structure and Curvature of Woven Fabric on the Luminescence Effect of Wearable Optical Fiber Fabric (직물의 세부 구조 및 굴곡이 웨어러블 광섬유의 발광 효과에 미치는 영향)

  • Yang, Jin-Hee;Cho, Hyun-Seung;Kwak, Hwy-Kuen;Oh, Yun-Jung;Lee, Joo-Hyeon
    • Science of Emotion and Sensibility
    • /
    • v.21 no.4
    • /
    • pp.55-62
    • /
    • 2018
  • The two main requirements of wearable optical fiber fabrics are that they must presuppose a high degree of flexibility and they must maintain the luminance effect in both flat and bent conformations. Therefore, woven optical fiber fabrics that satisfy the above conditions were developed by both weaving and by using computer embroidery. First, we measured the brightness of the wearable optical fiber fabric in the flat state at a total of 10 measurement points at intervals of 1 cm. Second, the wearable optical fiber fabric was placed horizontally on the forearm, where three-dimensional bending occurs, and the luminance values were recorded at the same 10 measurement points. For the woven fabric in the flat state, the maximum, minimum, average, and standard deviation luminance values were $5.23cd/m^2$, $2.74cd/m^2$, $3.56cd/m^2$, and $1.11cd/m^2$, respectively. The corresponding luminance values from the bent forearm were $7.92cd/m^2$ (maximum), $2.37cd/m^2$ (minimum), $4.42cd/m^2$ (average), and $2.16cd/m^2$ (standard deviation). In the case of the computer-embroidered fabric, the maximum, minimum, average, and standard deviation luminance values in the flat state were $7.56cd/m^2$, $3.84cd/m^2$, $5.13cd/m^2$, and $1.04cd/m^2$, respectively, and in the bent forearm state were $9.6cd/m^2$, $3.63cd/m^2$, $6.13cd/m^2$, and $2.26cd/m^2$, respectively. Therefore, the computer-embroidered fabric exhibited a higher luminous effect than the woven fabric because the detailed structure reduced light-loss due to the backside fabric. In both types of wearable optical fiber fabric the luminance at the forearm was 124% and 119%, respectively, and the light emitting effect of the optical fiber fabric was maintained even when bent by the human body. This is consistent with the principle of Huygens, which defines the wave theory of light, and also the Huygens-Fresnel-Kirchhoff principle, which states that the intensity of light increases according to the magnitude of the angle of propagation of the light wavefront (${\theta}$).

Structural Behavior Evaluation of NRC Beam-Column Connections (NRC 보-기둥 접합부의 구조적 거동 평가)

  • Jeon, Ji-Hwan;Lee, Sang-Yun;Kim, Seung-Hun
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.26 no.1
    • /
    • pp.73-80
    • /
    • 2022
  • In this study, details of NRC beam-column connections were developed in which beam and columns pre-assembled in factories using steel angles were bolted on site. The developed joint details are NRC-J type and NRC-JD type. NRC-J type is a method of tensile joining with TS bolts to the side and lower surfaces of the side plate of the NRC column and the end plate of the NRC beam. NRC-JD type has a rigid joint with high-strength bolts between the NRC beam and the side of the NRC column for shear, and with lap splices of reinforcing bar penetrating the joint and the beam main reinforcement for bending. For the seismic performance evaluation of the joint, three specimens were tested: an NRC-J specimen and NRC-JD specimen with NRC beam-column joint details, and an RC-J specimen with RC beam-column joint detail. As a result of the repeated lateral load test, the final failure mode of all specimens was the bending fracture of the beam at the beam-column interface. Compared to the RC-J specimen, the maximum strength of the specimen by the positive force was 10.1% and 29.6% higher in the NRC-J specimen and the NRC-JD specimen, respectively. Both NRC joint details were evaluated to secure ductility of 0.03 rad or more, the minimum total inter-story displacement angle required for the composite intermediate moment frame according to the KDS standard (KDS 41 31 00). At the slope by relative storey displacemet of 5.7%, the NRC-J specimen and the NRC-JD specimen had about 34.8% and 61.1% greater cumulative energy dissipation capacity than the RC specimen. The experimental strength of the NRC beam-column connection was evaluated to be 30% to 53% greater than the theoretical strength according to the KDS standard formula, and the standard formula evaluated the joint performance as a safety side.

On Vortex Reduction Characteristics of Pump Sump Circulating Water Intake Basin of Power Plant Using Hydraulic Experiment (수리실험을 이용한 발전소의 순환수 취수부 흡입수조의 와류저감에 관한 연구)

  • Eom, Junghyun;Lee, Du Han;Kim, Hung Soo
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.42 no.6
    • /
    • pp.815-824
    • /
    • 2022
  • Among the main facilities of the power plant, the circulating water used for cooling the power generation system is supplied through the Circulation Water Intake Basin (CWIB). The vortexes of various types generated in the Pump Sump (PS) of CWIB adversely affect the Circulation Water Pump (CWP) and pipelines. In particular, the free surface vortex accompanied by air intake brings about vibration, noise, cavitation etc. and these are the causes of degradation of CWP performance, damage to pipelines. Then power generation is interrupted by the causes. Therefore, it is necessary to investigate the hydraulic characteristics of CWIB through the hydraulic model experiment and apply an appropriate Anti Vortex Device (AVD) that can control the vortex to enable smooth operation of the power plant. In general, free surface vortex is controlled by Curtain Wall (CW) and the submerged vortex is by the anti vortex device of the curtain wall. The detailed specifications are described in the American National Standard for Pump Intake Design. In this study, the circulating water intake part of the Tripoli West 4×350 MW power plant in Libya was targeted, the actual operating conditions were applied, and the vortex reduction effect of the anti vortex device generated in the suction tank among the circulating water intake part was analyzed through a hydraulic model experiment. In addition, a floor splitter was basically applied to control the submerged vortex, and a new type of column curtain wall was additionally applied to control the vortex generated on the free surface to confirm the effect. As a result of analyzing the hydraulic characteristics by additionally applying the newly developed Column Curtain Wall (CCW) to the existing curtain wall, we have found that the vortex was controlled by forming a uniform flow. In addition, the vortex angle generated in the circulating water pump pipeline was 5° or less, which is the design standard of ANSI/HI 9.8, confirming the stability of the flow.

INDIVIDUALIZED RECONSTRUCTION OF THE LOWER OCCLUSAL PLANE ACCORDING TO SKELETAL PATTERN (안면 골격 형태에 따른 하악 교합평면의 재구성)

  • Hyun, Seong-Wook
    • The korean journal of orthodontics
    • /
    • v.25 no.4
    • /
    • pp.465-485
    • /
    • 1995
  • The purpose of this study is to locate the proper position of the lower occlusal plane according to individual skeletal pattern. Cephalometric films of 234 subjects of the control group, 358 of the pretreatment group and 358 of the treated group were analyzed to study proper relationships between vertical dimension ratio(VDR) and lower occlusomandibular plane angle(LOM). The control group was divided into two subgroups by the age. The first subgroup consisted of 113 subjects of the age 14 years and under and with the mean age of 10.82 years. The other subgroup consisted of 113 subjects of the age 18 years and above with the mean age of 23.76 years. The pretreatment group was divided into three subgroups by the age. The first subgroup consisted of 274 subjects of the age 14 years and under with the mean age of 11.36 years. The second subgroup consisted of 54 subjects of the age 14 through 18 years with the mean age of 15.4 years. The last subgroup consisted of 30 subjects of the age 18 years and above with the mean age of 21.35 years. The treated group was also divided into three subgroups by the age. The first subgroup consisted of 145 subjects of the age 14 years and under with the mean age of 12.91 years. The second subgroup consisted of 166 subjects of the age 14 through 18 years with the mean age of 15.64 years. The last subgroup consisted of 47 subjects of the age 18 years and above with the mean age of 21.61 years. Cephalometric films of the sample were traced. Measurements were made to a hundredth using a program specifically prepared for this study, and the results were entered into a 486DX PC. Means and Standard deviations of all the veriables were calculated for each group. Correlation coefficients between pertinent variables were calculated. Significance tests on those coefficients, one-way ANOVA and t-tests between variables or groups were performed. On the basis of the results studied above, certain subjects were selected from the control and the treated groups to locate the proper position of the occlusal plane, and designated as the optimal occluaion group. The subjects of this optimal occlusion group had 1-3 mm overbite, 1-3 mm of overjet and less than 1.75 mm of curve of Spee. A total subjects of 187 in this group consisted 104 treated subjects and 83 control group. Regression analysis was carried out between VDR and LOM, and regression equations were tabulated for this optimal occlusion group. The results were as follows : 1. Highly significant correlations were observed between various variables useful for identifying vertical component of skeletal frame, but any one particular variable did not accurately indicate the magnitude of anterior vertical overbite. 2. Of the variables useful identifying vertical component of skeletal frame, The VDR showed the highest correlation to the LOM. 3. Of the total sample, 80 percent had overbite within the normal range, irrespective of VDR. 4. The optimal occlusion group was divided into 9 subgroups by the age and the anteroposterior skeletal pattern, and correlation coefficient and determination coefficient between VDR and LOM of each group were calculated. Correlation coefficients and determination coefficients were found to be significantly high in all groups. 5. Regression equation was induced for each of the optimal occlusion group to find proper LOM according to the VDR. 6. It was found that the mean value of the cant of occlusal plane itself is not enough for a diagnosis and a treatment plan. Rather, It is very important to locate the proper occlusal plane for an Individual skeletal pattern.

  • PDF

Study on the Radial Pulse Wave Variables and Heart Rate Variability after Acupuncture Stimulation (침자극이 좌관맥상과 심박수 미세변화에 미치는 영향)

  • Won, Jae-Kyun;Jung, Soon-Kwan;Kim, Dong-Eun;Lim, Jin-Young;Kwon, Young-Dal;Yeom, Seung-Ryong;Lee, Su-Kyung;Song, Yung-Sun
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.23 no.1
    • /
    • pp.237-244
    • /
    • 2009
  • We investigated the effects of acupuncture stimulation on pulse wave variables and heart rate variability (HRV) in healthy adults. To evaluate twenty healthy volunteers (10 men, 10 women) had acupuncture into both Hapkok (Ll4) and Taechung (Liv3) for 15 minutes. Radial pulse, Heart Rate Variability, body temperature and blood pressure were checked before and after acupuncture to evaluate Pulse Wave Variability and Autonomous Function. The results were as follows; Heart rate was significantly increased while systolic blood pressure (mmHg) and diastolic blood pressure (mmHg) were significantly increased after acupuncture treatment. Sixteen subjects didn't change representative pulse wave variables after acupuncture treatment. Energy, height of main peak (H1), height of pre-dicrotic valley (H2) and height of descending valley (H4) were decreased while height of dicrotic peak (H5) was significantly decreased after acupuncture treatment. Time to main peak (T1), time to pre-dicrotic valley (T2), time to dicrotic peak (T5), total time (T) and T-T4 were decreased while time to descending valley (T4) was increased after acupuncture treatment. Total area (At), area of main peak (Aw) and ratio of diastolic period area (Ad) were decreased while ratio of systolic period area (As) and angle of main peak (MPA) were increased after acupuncture treatment. The standard deviation of all normal RR intervals (SDNN) was increased while the root mean square of successive differences between the normal heart beats (RMSSD) was significantly increased after acupuncture treatment by time domain analysis. Low frequency power (LF) and LF/HF ratio were decreased while high frequency power (HF) was significantly increased after acupuncture treatment by frequency domain analysis. This study suggests that acupuncture treatment changes pulse wave variability and heart rate variability. Further study on various acupuncture treatment for pulse wave variability and heart rate variability is required.

Optimal Design of Satellite Constellation Korean Peninsula Regions (한반도 지역의 효율적인 관측을 위한 최적의 위성군 설계)

  • Kim, Nam-Kyun;Park, Sang-Young;Kim, Young-Rok;Choi, Kyu-Hong
    • Journal of Astronomy and Space Sciences
    • /
    • v.25 no.2
    • /
    • pp.181-198
    • /
    • 2008
  • Designing satellite constellations providing partial coverage of certain regions becomes more important as small low-altitude satellites receives an increasing attention due to its cost-effectiveness analysis. Generally, Walker's method is a standard constellation method for global coverage but not effective for partial coverage. The purpose of this study is to design optimal constellation of satellites for effective observation in Korean peninsula regions. In this study, a new constellation design method is presented for partial coverage, using direct control of satellites' orbital elements. And also, a ground repeating circular orbit is considered for each satellite's orbit with the Earth oblateness effect. As the results, at least four satellites are required to observe the Korean peninsula regions effectively when minimum elevation angle is assumed as 12 degrees. The results from new method are better than those from the best Walker method. The proposed algorithm will be useful to design satellite constellation missions of Korea in future.

Evaluation of Intralimb Coordination in Transfemoral Amputee during Level Walking (대퇴절단인의 보행 시 하지 내 협응성 평가)

  • Chang, Yoon-hee;Jeong, Bo-ra;Kang, Sung-jae;Ryu, Jei-cheong;Mun, Mu-seong;Ko, Chang-Yong
    • Journal of rehabilitation welfare engineering & assistive technology
    • /
    • v.10 no.2
    • /
    • pp.147-153
    • /
    • 2016
  • The aims of this study were to evaluate the joint coordination between hip and knee joints in the transfemoral amputees, and its symmetry between sound and prosthetic limbs. Seven transfemoral amputees ($46.4{\pm}10.7-year-old$, $174.8{\pm}3.5cm$, $78.3{\pm}9.7kg$) and 7 able bodies ($24.0{\pm}4.5-year-old$, $174.5{\pm}5.9cm$, $66.9{\pm}9.4Kg$) participated in this study. They walked at a self-selected walking speed across a 10m level ground. Simultaneously angle and angular velocity in the hip and knee joint were measured by motion analysis system. Then continuos relative phase(CRP), standard deviations of CRP (CRP_SD) and symmetry index(SI) were calculated. In able bodies, there were no differences of the parameters between left and right limb(all p>0.05). However, significant differences between sound and prosthetic limb in most of the parameters, except for CRP for stance phase were shown (all p<0.05). There were differences in all SI between transfemoral amputees and able bodies (p<0.05). In conclusion, joint coordination was altered in transfemoral amputee during level walking and shown in interlimb asymmetry.

CHARACTERISTICS OF CRANIOFACIAL MORPHOLOGY IN ADULT WITH CROWDED DENTITION (밀집치열인의 두개안면골의 형태학적 특성)

  • Jeon, Jun-Young;Sung, Jae-Hyun
    • The korean journal of orthodontics
    • /
    • v.18 no.2
    • /
    • pp.421-433
    • /
    • 1988
  • The purpose of this study was to investigate the characteristics of craniofacial morphology in adult with crowded dentition. The craniofacial morphology associated with normal and crowded of mandibular dentition was studied in lateral cephalometric radiograph obtained from 145 subjects grouped 44 males and 40 females in normal group, 33 males and 28 females in crowded group. The conclusions were as follows: Means, standard deviations and facial polygons from measurements were obtained from normal and crowded groups. Palatal plane to SN, occlusal plans to SN, mandibular plane to SN, mandibular plane to palatal plane and gonial angle measurements of crowded group were significantly different from normal group and were larger than normal group. SNA, SNB measurements of crowded group were significantly different from normal group and were smaller than normal group. Significant differences were observed between normal group and crowded groups on the basis of $SN/{\underline{1}}$, PP/1, $MP/{\bar{1}}$, and compared with normal group, upper incisors of crowded group were inclined more labially, whereas lower incisors of crowded group were inclined more lingually. Posterior facial height and ramal height were shorter in males of crowded group than those of normal group. Posterior facial height, mandibular length and posterior cranial base length were shorter in females of crowded group than those of normal group. Anterior facial height was longer in females of crowded group than those of normal group.

  • PDF

The Evaluation for Pullout Performance of Steel Strip Reinforcements with Deformed-Bars as Transverse Members (지지부재로 이형철근을 설치하는 띠형 강보강재의 인발성능 평가)

  • Jung, Sung-Gyu;Kim, Juhyong;Cho, Samdeok;Lee, Kwangwu
    • Journal of the Korean Geosynthetics Society
    • /
    • v.12 no.4
    • /
    • pp.77-86
    • /
    • 2013
  • Laboratory pullout tests were conducted to evaluate pullout performance of steel strip reinforcements with deformed steel bars as transverse members. The steel strip reinforcement has an installation hole to assemble a deformed steel bar. Jumunjin standard sand is used to form a relative density of ground model to 80%. Frictional resistance of steel strip reinforcement without transverse member increases sharply at the initial displacement and quickly decreases with displacement. Maximum frictional resistance increases linearly as normal pressure increasing, and soil-reinforcement interaction friction angle(${\rho}_{peak}$) of a steel strip reinforcement is estimated to $14.64^{\circ}$. Passive resistance increases with displacement and converge into maximum passive resistance in most cases. Maximum passive resistance increases linearly as normal pressure increasing irrespective of shape of the steel reinforcement. Pullout force of steel strip reinforcements with installation holes or transverse members largely increases about 4 to 7 times compared to frictional resistance force of steel strip reinforcements when embedment length($L_e$) of steel strip reinforcements is 500 mm. In the case of using 2 transverse members, interference effect is observed due to the spacing of 2 transverse members and location of assembly holes and transverse members.

An Experimental Study on Stress-Strain Behavior of Sands under Three Dimentional Stress (삼차원(三次元) 응력조건하(應力條件下)의 모래의 응력(應力)-변형거동(變形擧動)에 관한 실험적(實驗的) 연구(硏究))

  • Chung, Hyung Sik;Chun, Byung Sik;Lee, Hyoung Soo;Koh, Yong Il
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.11 no.1
    • /
    • pp.153-166
    • /
    • 1991
  • In an attempt to investigate the effect of intermedate principal stresses which are related to the stress-strain behavior of standard sands, a series of three-Principal stress control tests were conducted for individual stress paths. The results have shown that shear strengths of sands vary with the stress paths. The variations in internal friction angle are accorded with the Habibs stress parameter, b which represents Stress paths, showing on abropt increase at the values between 0.0 and 0.268, a moderate level between 0.268 and 0.682, and a slight decrease between 0.682 and 1.0 However, the friction angles under a triaxial extention state, were found relatively larger than under a triaxial compression state. In general, such veriations were found to have the same tendency without any relevant relation with the density of specimens and confining pressures. Therefore, it is concluded, that the shear strength of sands are positively influeced by the intermediate principal stresses present in the media. And the influnce of intermediate principal stresses on shear strengths of sands found from the present study are well compared with the previous studies by Lade-Duncan and Matsuoka-Nakai revealing a similar tendency within the failure criteria proposed by them.

  • PDF