• 대한안전경영과학회지
• /
• 제11권2호
• /
• pp.103-110
• /
• 2009

The purpose of this study is to suggest a proper tread of stairs using kinematic factors and moments of the lower-limb joints in the stair decent with the 3 different treads with boimechanical method in ergonomics. 9 subjects (body masses; $59.41{\pm}7.49$, $64.03{\pm}6.65$, $67.26:{\pm}7.58$, heights; $160.50{\pm}6.35$ ages; $31.22{\pm}2.99$; parity; $1.67{\pm}0.71$) participated in three experiments that were divided by physiological symptoms (the early (0-15 weeks), middle (16-27 weeks) and last (18-39 weeks). and they walked at self-selected pace on 4 staircases 3 trials. As extending the pregnancy period, cadence was shorter but cycle time were longer more and more. As extending treads of stair decent during pregnancy, speed, stride lengths and cycle time were increased. As extending the treads of stair decent, hip and ankle moments increased but knee moments decreased in sagittal plane. There were increasing or decreasing of moments by means of treads. These changes may account for relation between the treads of stair and moments in pregnant women. The main changes of pregnant women were joint moments and kinematic factors during pregnancy period because pregnancy makes them physical changes. It is possible that joints have connection with compensation each other to maximize stability and to control gait motion. In conclusion, we suggest that the tread of stair is longer than 26cm tread. and exercise programs to improve muscle activity were necessary where joint moments were small.

• Design & Manufacturing
• /
• 제12권2호
• /
• pp.27-33
• /
• 2018

Korea's automobile industry, which has grown rapidly to become the world's fifth-largest automobile producer, To cope with environmental pollution and energy problems in order to prevail competitive edge in global market We are investing a lot of research personnel and costs. Among them, for realizing alternative light weight It is a part of the automobile module system that has achieved the technological development before the breakthrough in the injection molding process in the press process. Door module PNL was the subject of research. The door module PNL is expected to cause warpage before the mold production due to the thin and flat product characteristics and fiber orientation characteristic of the material. In this paper, CAE analysis and reverse correction tool Design. CAE analysis to obtain the results of weld line position, bending position and deformation value Through the correction tool, think3, the original product was modified before the mold production to improve the completeness of the parts. In fiber orientation, the position and size of the cooling channel in the mold, the position and size of the gate, Temperature, pressure, time, and work environment. Compared with the result of CAE analysis, the product that was reverse-corrected by Think3 was manufactured, and injection molding was performed. Injection molding products were tested 24 hours later. 3.5 mm to 7.0 mm, and under the fixed condition, the deviation was from 1.1 mm to 1.5 mm. Unlike the CAE analysis, the deviation of the actual injection pressure and the cooling temperature, the fiber orientation of the material, In order to solve this problem, it is necessary to compare the injection conditions with the database, I knew I had to catch the standard.

• 한국전자파학회논문지
• /
• 제26권4호
• /
• pp.397-403
• /
• 2015

본 논문은 임펄스 초광대역 레이다를 이용한 ISAR 영상의 기하보정 방법에 대해 서술하였다. 임펄스 초광대역 레이다는 시간영역에서 신호처리를 하므로 다중 경로, 간섭 문제 등이 일어나지 않는 장점이 있다. 안테나와 대상체 사이의 송수신 신호를 평면파라고 가정하면, ISAR 기하 모델에서 회전축의 중심을 점표적을 이용하여 계산한다. 수신 데이터에서 합성을 수행하기 전, 점표적은 최대 점의 위치를 최소 자승법으로 근사하여 회전축의 중심을 알아낼 수 있다. 이 방법은 대조비가 더 뛰어난 영상을 얻을 수 있었고, 엔트로피도 가장 큰 값을 가질 수 있었다. 이러한 방법은 장비를 최초 작동하거나 주기적으로 사용되어서 회전축의 중심을 보상하여 영상 합성을 할 것이다. 의료나 보안 감시와 같은 고정된 기하를 가지는 영상화 장비에서 유용하게 사용될 것이다.

• 한국항행학회논문지
• /
• 제26권6호
• /
• pp.474-480
• /
• 2022

광 위상 공액은 파장 분할 다중 (WDM; wavelength division multiplexed) 신호의 장거리 전송을 위해 필수적인 색 분산과 비선형성에 의한 왜곡을 보상할 수 있는 기술 중 하나이다. 이 기술이 그동안 가지고 있었던 한계를 주기적 분산 프로파일을 갖는 분산 맵을 통해 해소하는 방안을 제안하고 분석해 보았다. 제안하는 시스템에서 광 위상 공액기 (OPC; optical phase conjugator)는 전체 링크의 1:2 또는 2:1의 위치에 배치되고, 분산 맵의 프로파일은 사인파 또는 반전된 사인파 모양의 주기적 형태를 갖는다. OPC가 전체 링크의 2:1 지점이 아닌 1:2 지점에 위치할 때 제안된 주기적 형태의 분산 맵을 통해 왜곡된 960 Gb/s WDM 신호의 보상이 더욱 개선되는 것을 확인하였다. 또한 제안된 주기적 분산 맵을 갖는 분산 제어 링크의 설계 융통성을 늘리기 위해서는 중계 구간에 할당되는 최대 RDPS (residual dispersion per span)가 1,800 ps/nm 이상이 되어야 하는 것도 알 수 있었다.

• 대한전자공학회논문지SP
• /
• 제44권2호
• /
• pp.63-73
• /
• 2007

본 논문에서는 실외 환경에서 모바일 디스플레이에 발생하는 명순응 현상과 섬광(flare)을 고려하여 주변광원에 적응적인 모바일 디스플레이에서의 색 재현을 제안하였다. 실외 환경에서 디스플레이된 영상은 인간 시각의 명순응 현상에 의해서 어둡게 인지되고 섬광으로 인하여 장치의 밝기는 다소 높아지지만 채도가 감소하는 현상이 발생한다 이러한 현상을 해결하기 위하여 입력 영상의 밝기를 향상하고 채도를 보상하여 실외에서 영상을 보더라도 실내에서와 유사한 영상으로 인지되도록 하였다. 첫째, 주변광원의 밝기는 조도센서를 사용하여 측정하고, 디스플레이의 반사율을 측정하여 해당 조도 하에서의 섬광을 계산하게 된다. 영상의 밝기는 주변광원의 밝기에 따라 변화하는 추상체(cone) 응답이 선형적으로 되도록 역변환 하여 향상하였다. 다음은 섬광으로 인하여 발생하는 물리적인 채도 저하 현상은 이것이 발생하기 전과 후의 차를 이용하여 그 크기만큼을 보상해 주었다. 결과적으로 제안한 방법을 적용한 영상을 실외 환경에서 보았을 때 기존의 어둡게 보이고 채도가 낮아지던 현상이 향상됨을 실험을 통하여 알 수 있었다.

• Journal of Chest Surgery
• /
• 제16권2호
• /
• pp.213-220
• /
• 1983

Pulmonary function is the determinant of blood gas tension. However, Acid-Base disturbances can also alter partial pressures of oxygen and carbon dioxide in arterial blood. During respiratory acidosis $PO_2$ will be lowered and reverse changes will be produced during respiratory alkalosis. On the other hand, in metabolic acidosis $PO_2$ will be elevated and $PCO_2$ will be lowered by the respiratory compensation, and reverse response will be induced in metabolic alkalosis. Urinary gas tension has many influencing factors than arterial blood and difficult to estimate the tendency of its alterations. Urinary $PO_2$ and $PCO_2$ are not always identical level as venous blood. It is to be altered by blood gas tension, flow rate of urine, metabolic rate of kidney, and Acid-Base status of blood. Particularly countercurrent exchange of oxygen and carbon dioxide in the renal medulla will make larger alteration of gas tension than venous blood. After induction of Acid-Base disturbances [disturbances] arterial and urinary $PCO_2$, $PO_2$, urinary volume, and osmolarity were determined in dogs, and the relationships between arterial and urinary $PCO_2$ , $PO_2$ Acid-Base disturbances, urinary volume, and osmolarity were investigated. 1. During the acute Metabolic and Respiratory disturbances urinary pH did not respond on respiratory origin. However, there were immediate urinary response in pH on metabolic origin. 2. Urinary $PO_2$, $PCO_2$, did not always follow arterial or venous gas tension and Acid-Base disturbance. Urinary $PCO_2$, correlate well with the urinary volume. The larger the urinary volume, $PCO_2$ lowered to the venous level. The smaller the urinary volume, urinary $PCO_2$ tends to be higher. However urinary $PO_2$ did not have any particular correlation with urinary volume. 3. Correlation between urinary $PCO_2$ and $PO_2$ were inversely proportional to arterial blood. Differences of $PCO_2$ between arterial blood and urine also did not have any particular correlation with urinary volume. This may suggest that changes on blood gas tensions can influence on urinary $PCO_2$. 4. There were eminent clear inverse correlation between urinary $PCO_2$ and osmolar concentrations of urine. Above results strongly suggest that partial pressure of gas in urine primarily depend upon counter-current exchanges in renal medullary tissues.

• 동의신경정신과학회지
• /
• 제21권4호
• /
• pp.21-39
• /
• 2010

Objectives : This study was to investigate the characteristics of the heart rate variability(HRV), types of insomnia and accompanying symptoms of 175 insomnia patients. Methods : For this study we carried out HRV, Inbody of 175 patients with insomnia who have come to Dongeui oriental hospital of Dongeui university from the period of Janaury 2008 to September 2010. We studied the association of the insomnia patients' age and gender with HRV, accompanying symptoms and the types of insomnia. The information of the accompanying symptoms and types of insomnia was based on each patients' progress note. Results : l. There was no significant differences in the characteristics of HRV between male and female. 2. The most frequent symptom shown among the insmonia patents' was headache(41.14%). 3. Comparing the symptoms between the gender, female patients had more dry mouth, alternative periodic chill and fever, and hot flush symptoms than the male patients. 4. Comparing the symptoms between the age groups(divided in two), the lower age group (20~59) had more dizziness and constipation symptoms than the higher age group (over 60). 5. Comparing the types of insomma between the age group, the higher age group (over 60) had more termination insomnia. 6. The types of insomnia of the entire insomnia patients were onset insomnia (73.1%), maintenance insomnia(20.6%), termination insomma(l7.1 %), shallow sleep (52.6%), listed by order of frequency. 7. The patients who takes hypnotics had more anorexia symptoms than the patients who doesn't take hypnotics. 8. There was no visible differences of the average fractal portrait between male and female. The age group of 20~30yrs. had the highest average fractal portrait, and the age group of 30~59yrs. the second highest, and the age group over 60yrs. the lowest. 9. The average of the regulation reserves of the autonomic nervous system(B2) - was lower than the regulation level of the ANS at the present (Bl). 10. When compared the priority of the function of the ANS, it showed that the proportion of HF($38.61{\pm}29.19%$)was the most, and than VLF($30.65{\pm}23.36%$), LF($20.04{\pm}19.13%$) the least. 11. The average of the compensation level of the central nervous system at present(Cl) - was lower than the compensation reserves of the CNS(C2). 12. The average of the control reserves of the cerebrum(D2) - was lower than the control level of the cerebrum at the present (Dl). 13. There was no visible differences between different sexes and ages in pulse rate. 14. The abdomen fat ratio above the line of the insomnia patients was 77.97% in male and 93.1% in female. Both sexes showed that insomnia patients had more abdomen fat that the standard, and female patients had more abd. fat than male patients. Conclusions : This study shows that the HRV of insomnia patients had no significant differences between gender. Fractal portrait, HF, LF and VLF of the insomnia patients are in inverse proportion to the age. The study of the Body Component Analysis showed that female had more abdomen fat than male, and both gender showed more abdomen fat than the standard. When looked into the accompanying symptoms of the insomnia patients, the symptoms show differences according to gender, age and hypnotics taking, as shown as below. In the entire patients, Headache was the most accompanying symptom. Female had more dry mouth, alternative periodic chill and fever, and hot flush symptoms than male. Higher age groups had more dizziness and constipation as accompanying symptoms than lower age groups. Patients who takes hypnotics had more anorexia than those who dont.