• Title/Summary/Keyword: declination

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Analysis of Static Stability by Modified Mathematical Model for Asymmetric Tractor-Harvester System: Changes in Lateral Overturning Angle by Movement of Center of Gravity Coordinates

  • Choi, Kyu-hong;Kim, Seong-Min;Hong, Sungha
    • Journal of Biosystems Engineering
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    • v.42 no.3
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    • pp.127-135
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    • 2017
  • Purpose: Purpose: The usability of a mathematical model modified for analysis of the static stability of an asymmetric tractor-harvester system was investigated. Method: The modified asynchronous mathematical model was validated through empirical experiments, and the effects of movements of the center of gravity (CG) coordinates on the stability against lateral overturning were analyzed through simulations. Results: Changes in the lateral overturning angle of the system were investigated when the coordinates of the CG of the system were moved within the variable range. The errors between simulation results and empirical experiments were compared, and the results were -4.7% at the left side overturning and -0.1% at the right side overturning. The asymmetric system was characterized in such a way that the right side overturning had an increase in overturning angle in the (+) variable range, while it had a decrease in overturning angle in the (-) variable range. In addition, the left side overturning showed an opposite result to that of the right side. At the declination angle (296<${\gamma}$<76), the right side overturning had an increase in the maximum overturning angle of 3.6%, in the minimum overturning angle of 20.3%, and in the mean overturning angle of 15.9%. Furthermore, at the declination angle (284<${\gamma}$<64), the left side overturning had a decrease in the maximum overturning angle of 29.2%, in the minimum overturning angle of 44%, and in a mean overturning angle of 39.7%. Conclusion: The modified mathematical model was useful for predicting the overturning angle of the asymmetric tractor-harvester system, and verified that a movement of the CG coordinates had a critical effect on its stability. In particular, the left side overturning was the most vulnerable to stability, regardless of the direction of declination angle.

Optical analysis of low concentration evacuated tube solar collector

  • Teles, Mavd R.;Carvalho, Raquel;Ismail, Kamal A.R.
    • Advances in Energy Research
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    • v.5 no.3
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    • pp.227-237
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    • 2017
  • The continuous increase of emission rates of green house gases and the effects on global warming added a new dimension to the problem of substituting the petroleum and its derivatives by environment friendly and sustainable energy sources for the world. Solar and wind energy appear at the top of the list of renewable of high potential, widely available, of dominated technology and well accepted. Brazil is one of the few countries in the world that receives number hours of sunshine exceeding 3,000 hours per year with a daily average of 4.5 to 6 kWh. However, this potential is largely unexplored and poorly tapped. The number of renewable systems implanted in Brazil has grown in recent years, but still insignificant when compared, for example, with Germany and Spain among others. This paper presents the results of an optical study on small concentration solar collector with evacuated tube enveloping the absorber and internal reflective surface fixed on the bottom part of the evacuated tube. The designed collector has a 2D geometrical concentration ratio between 2.455 and 4.91. The orientation of the solar collector, the ratio of the radius of the receiver to the radius of the absorber, the incidence angle for each period of the year, the collector inclination angle, the aperture angle of the reflective surface, concentration and optical efficiency were determined. The ray traces and flux distribution on the absorber of the evacuated tube solar collector were determined by using the program Ray Optics Simulation. The optical efficiency varies during the year according to the solar declination. For the periods were the solar declination is close to zero the efficiencies are maximum, and the variation during the day is around 25.88% and 99.9%. For the periods were the solar declination is maximum the efficiencies are minimum, and the variation during the day is around 23.78% and 91.79%.

The Structural Characteristics of the Ankle Joint Complex and Declination of the Subtalar Joint Rotation Axis between Chronic Ankle Instability (CAI) Patients and Healthy Control (만성 발목 불안정성(CAI) 환자와 건강 대조군 간의 발목 관절 복합체 구조적 특징과 목말밑 관절 회전 축 기울기)

  • Kim, Chang Young;Ryu, Ji Hye;Kang, Tae Kyu;Kim, Byong Hun;Lee, Sung Cheol;Lee, Sae Yong
    • Korean Journal of Applied Biomechanics
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    • v.29 no.2
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    • pp.61-70
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    • 2019
  • Objective: This study aimed to investigate the characteristics of the declination of the subtalar joint rotation axis and the structural features of the ankle joint complex such as rear-foot angle alignment and ligament laxity test between chronic ankle instability (CAI) patients and healthy control. Method: A total of 76 subjects and CAI group (N=38, age: $23.11{\pm}7.63yrs$, height: $165.67{\pm}9.54cm$, weight: $60.13{\pm}11.71kg$) and healthy control (N=38, age: $23.55{\pm}7.03yrs$, height: $167.92{\pm}9.22cm$, weight: $64.58{\pm}13.40kg$) participated in this study. Results: The declination of the subtalar joint rotation axis of the CAI group was statistically different from healthy control in both sagittal slope and transverse slope. The rear-foot angle of CAI group was different from a healthy control. Compared to healthy control, they had the structure of rear-foot varus that could have a high occurrence rate of ankle varus sprain. CAI group had loose ATFL and CFL compared to the healthy control. Conclusion: The results of this study showed that the deviation of the subtalar joint rotation axis and the structural features of the ankle joint complex were different between the CAI group and the healthy control and this difference is a meaningful factor in the occurrence of lateral ankle sprains.

STUDY ON THE RESTORATION MODEL OF JEONGNAM-ILGU, CREATED DURING THE REIGN OF KING SEJONG OF THE JOSEON DYNASTY (조선 세종대에 창제된 정남일구 복원모델 연구)

  • JIWON PARK;BYEONG-HEE MIHN;SANG HYUK KIM;YONG-GI KIM
    • Publications of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.1-12
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    • 2023
  • Numerous Sundials were fabricated during the reign of King Sejong of the Joseon Dynasty. One among them is Jeongnam-Ilgu (the Fixing-South Sundial), where the time can be measured after setting up the suitable meridian line without a compass. We reconstructed the new Jeongnam-Ilgu model based on the records of 'Description of Making the Royal Observatory Ganui (簡儀臺記)' in the Veritable Record of King Sejong. Jeongnam-Ilgu has a summer solstice half-ring under a horizontal ring which is fixed to two pillars in the north and south, and in which a declination ring rotates around the polar axis. In our model, the polar axis matches the altitude of Hanyang (that is Seoul). There are two merits if the model is designed to install the polar axis in the way that enters both the north and south poles and rotates in them: One is that it is possible to fix the polar axis to the declination ring together with the cross-strut. The other is that a twig for hanging weights can be protruded on the North Pole. The declination ring is supposed to be 178 mm in diameter and is carved on the scale of the celestial-circumference degrees on the ring's surface, where a degree scale can be divided into four equal parts through the diagonal lines. In addition, the time's graduation that is drawn on the summer solstice half-ring makes it possible to measure the daytime throughout the year. An observational property of Jeongnam-Ilgu is that a solar image can be obtained using a pin-hole. The position cast by the solar image between hour circles makes a time measurement. We hope our study will contribute to the restoration of Jeongnam-Ilgu.

Burnout among Clinical Dental Hygienists and Its Coping Behaviors (임상치과위생사들의 직무소진과 대처행동)

  • Kim, Young-Sun;Yoon, Hee-Suk
    • Journal of dental hygiene science
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    • v.7 no.4
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    • pp.225-233
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    • 2007
  • This study, to investigate the job burnout and coping behaviors that clinical dental hygienists feel in the work process, has collected 322 clinical dental hygienists working in Daegu, Kyungbuk province, and Ulsan and had a conclusion as follows. 1. The average of area job burnout and coping behaviors were as follows; emotional burnout, 3.26, cynical manners, 2.63, the declination of job efficiency, 2.58, the total average, 2.82. 2. The average of area were as follows; active coping, 3.36, passive coping, 2.95, and the total average, 3.19. 3. The difference of job burnout relating to general characteristics was shown that the lower education level and age they were in, the significantly higher the declination of job efficiency and burnout area were. The unmarried had significantly higher points at cynical manners, the declination of job efficiency and burnout. Besides, the introspective had significantly higher points at emotional exhaustion, cynical manners, and burnout area. 4. The difference of job burnout related to working circumstance was shown that those with short working experience and those in charge of the general treatment showed significantly high points at the declination of job efficiency. And the less annual salary, the significantly higher points at cynical manners, the declination of job efficiency and burnout area. 5. In the correlation between job burnout and coping method, burnout area has a significantly normal correlation with active coping and coping area, whereas, it has significantly abnormal correlation with passive coping. 6. As for the difference of area burnout relating to coping behaviors, in coping area A group(under average) had significantly higher points than B group(over average) at the declination of job efficiency and burnout area. From the above results, it was proved that the clinical dental hygienists in younger age, with shorter work experience and less annual salary, no marital spouse had higher points at burnout and passive coping.

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The clinical study of the effect of Jamyang.Jaum prescriptions on the hypertension evolution in cerebral hemorrhage patients (잠양자음약물(潛陽滋陰藥物)이 뇌출혈(腦出血) 환자(患者)의 고혈압(高血壓)에 미치는 영향(影響)에 대한 임상적(臨床的) 고찰(考察))

  • Choi, Cheol-Won;Kim, Dong-Woung;Shin, Sun-Ho;Jeon, Heui-Jun;Hwang, Bo-Youn;Jeong, Dae-Young
    • The Journal of Korean Medicine
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    • v.18 no.1
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    • pp.72-81
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    • 1997
  • The causes of stroke are presumed hypertension, atherosclerosis,. cardiac disease, diabetes mellitus and old age and risk factors of stroke are suggested hypertension, hyperlipidemia. obesity, smoking and drinking etc. Especilly, hypertension is one of the most important cause and risk factor of stroke, therfore without therapy hypertension leads to stroke. The frequence of hypertension is significantly higher in hemorrhage patients of intracranial hemorrhage and subarachnoid hemorrhage. Antihypertensive therapy has an impact not only on the primary prevention of stroke but also on stroke recurrence and the declining of stroke motality has been attributed to the widespread availability and use of antihypertensive therapy. The goals of antihypertensive therapy decrease the complications and motalitv of cardiovascular system and prevent the promoting arteriosclerosis. In this study, we observed the blood pressure change of cb-hemorrhagic patients with hypertension who were hospitalized from 1996. 3. 1 to 1997. 2 .26 in Wonkwang Oriental Hospital. These patients had no antihypertensive therapy and were supplied herb med(Jaum sikpoongtang, Chungrijagamtang, Gojinumja) in medication. Our results suggested as follows. 1. Systolic and diastolic average BP at admission is $150.71{\pm}15.61mmHg$ and $95.00{\pm}8.8mmHg$ and this is hypertension state defining WHO 2. During one week in admission, the blood pressure demostrated a marked declination by SBP 8.97mmHg and DBP 6.22mmHg. 3. During two week in admission, the declination of SBP was significant in paired t-test(p<0.05) but, the declination of DBP was non-significant in paired t-test. 4. The blood pressure during third and fourth weeks gradually declined but, non-significant in test. According to the above results, we suggested that the BP declination Was affected by $Jamyang{\cdot}Jaum$ prescriptions in acute stage of cerebral hemorrhage.

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The Effects of Declination and Curvature Weight in DEM (수치표고모형에서 경사와 곡률경중율의 영향)

  • Yang, In-Tae;Choi, Seung-Pil;Kwon, Hyun;Kim, Wook-Nam
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.8 no.2
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    • pp.45-51
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    • 1990
  • DEM must have a high accuracy against the actual topographic model. A model which can compute heights responding to random plane position by using of the topographic data and interpolation must be constructed. Interpolation affected by the accuraccy of the observations included noise, which affected by the slop and curvature weight. Data smoothing is a method to reduce the noise. Average declination and area ratio are variable which result similarity in according to slope. But in local area, area ratio well shows a local change. This study try to classify the terrain by the declination to analysis the effects of the declination and curvature weights, and then to represent the most probable model. The result are following : In terrain classification by the slop, p16 and p24 were fitted in the plane surface fit p16 and S in the varying surface, and S and p24 in the irregular surface in classification by curvature, p24 and S were fitted in the plane or varying surface, and p16 in the irregular surface In case of hybrid, p16, p24 and S are fitted in the plane, varying and irregular surface respectively. Smoothing is the most effective in case of slope of 50 persentage and of curvature weight of 0.0015.

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Subtalar Arthrodesis using Cannulated Screws and Morselized Bone Graft (유관 나사와 분쇄 골이식을 사용한 거골하 관절 유합술)

  • Ahn, Jae-Hoon;Kim, Kap-Jung;Choy, Won-Sik;Na, Kyu-Hyun
    • Journal of Korean Foot and Ankle Society
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    • v.10 no.1
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    • pp.66-70
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    • 2006
  • Purpose: To analyze the clinical and radiological outcome of subtalar arthrodesis using cannulated screws and morselized bone graft. Materials and Methods: Twenty one patients with follow-up of more than 1 year after subtalar arthrodesis were included in this study. Mean age was 40.8 years, and mean follow-up duration was 38 months. Underlying diseases were 19 cases of posttraumatic arthritis (18 calcaneal fractures and 1 talar fracture) and 2 cases of tarsal coalition. Clinically AOFAS ankle-hindfoot score, operation time, complication and satisfaction of patients were analyzed. Radiologically time to union, arthritis of surrounding joints, preoperative and postoperative talar declination angle were analyzed. Results: AOFAS ankle-hindfoot score was improved from preoperative 33 points to postooperative 79 points. Eighteen patients (86%) were satisfied with the results. Mean operation time was 91 minutes. All cases were fixed with 1-2 cannulated screws and morselized bone graft. Mean time to radiologic union was 12.1 weeks. There was 1 case of delayed union. There was no significant perioperative changes in talar declination angles. Conclusion: Subtalar arthrodesis using cannulated screws and morselized bone graft seems to be relatively simple and effective treatment method for subtalar arthritis.

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A Study on the Power Performance Measurement of Transparent Thin-film PV Windows of BIPV Depending on the Inclined Angle (건물일체형 투명 PV복층창의 설치조건에 따른 단위출력당 발전특성 분석연구)

  • An, Young-Sub;Song, Jong-Hwa;Kim, Seok-Ge;Lee, Sung-Jin;Yoon, Jong-Ho
    • 한국태양에너지학회:학술대회논문집
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    • 2008.04a
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    • pp.55-60
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    • 2008
  • This study is on the analysis of power output of transparent thin-film PV windows which are integrated into the building envelope instead of traditional windows. 3 installation angles of vertical, horizontal and $30^{\circ}C$ inclination are investigated. To measure power output of PV windows, full scale mock-up house was designed and constructed. The power performance of PV window system was analyzed for horizontal angle, declination angle and vertical angle according to incline angle. Monitoring data are gathered from November 2006 to August 2007 and statistical analysis is performed to analysis a characteristics of power performance of transparent PV windows. Results show that annual power output of PV window with horizontal angle is 844.4kWh/kWp/year, declination angle 1,060kWh/kWp/year and vertical angle 431.6 kWh/kWp/year.

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Automatic Recognition of Hand-written Hangout by the Phase Rotation (위상회전에 의한 필기체 한글의 자동인식)

  • 이주근;김홍기
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.13 no.1
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    • pp.23-30
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    • 1976
  • In this paper, a method is proposed for the recognition of hand-written Hangeul. This is peiformed by extraction of the concave structural segments by phase rotation. Character patterns can be decomposed into the fundamental concave structural segments which are also categorized into segment sects, and the closure and phase features of each segment in set is represented by logics. By rotating the logic pattern, the topological and phase features of segment are extracted for the reliable recognition of the character. It is also evaluated that this method applies to a wide variety of shape, position and declination of the character.

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