• Title/Summary/Keyword: aging process

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냉음극 방전관의 기동특성 안정화에 관한 연구 1

  • 지철근
    • 전기의세계
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    • v.14 no.3
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    • pp.18-27
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    • 1965
  • It is well known that the starting characteristics of the cold cathode type discharge tubes are irregular. We have two kinds of stabilization for starting characteristics of discharge tubes. Which are the aging test immediately after producing the tubes and the using characteristics. This paper was devoted primaliry to the empric study of relation between the aging and the manufacturing process. And then to stabilize the starting characteristics of discharge tubes by the irradiations of radio-isotope.

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Sarcopenia and Neurosurgery

  • Park, Seung Won
    • Journal of Korean Neurosurgical Society
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    • v.56 no.2
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    • pp.79-85
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    • 2014
  • Aging process can be characterized as a spontaneous decrease of function in various organs with age. Muscle, as a big organ of human body, undergoes aging process presenting with loss of muscle mass, "sarcopenia". Recently, several working groups have tried to make consensus about sarcopenia for definition and diagnosis. Muscle mass is known to be closely related with bone, brain, fat, cardiovascular and metabolic systems. With increased understanding, clinical and basic researches about sarcopenia have been also increased rapidly from various areas of health science and technology. In this paper, the history and recent concepts of sarcopenia were reviewed and brief discussion of its prospect in the field of neurosurgery was done.

0.7 inch FED Panel system build-up by using proper sealing process

  • Kwon, Sang-Jik;Hong, Kun-Jo;Cho, Tae-Hee;Lee, Jong-Duk;Oh, Chang-Woo;Kwon, Yong-Bum
    • Journal of Korean Vacuum Science & Technology
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    • v.3 no.1
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    • pp.85-89
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    • 1999
  • FDE panel was successfully fabricated through the integration of a 0.7" diagonal Si-based Mo-tip FEA with 25${\times}$25 pixels, Y2O3:Eu or ZnO:Zn phosphor screen, and vacuum sealing through an exhausting glass tube, including a getter. The panel system was driven by an external driver circuit having pulse width modulation(PWM) driving scheme. Before character imaging, it was stabilized through tip aging by slowly increasing a pulse-mode emission current and phosphor aging by a coulombic charging process. After aging, luminescent characteristics such as emission uniformity, charging and arcing phenomena were shown to be improved significantly.

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Effect of Humidity on Physico-chemical Properties of Hydrous Aluminum Oxide

  • Rhee, Gye-Ju;Han, Kwan-Sub
    • YAKHAK HOEJI
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    • v.21 no.2
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    • pp.101-109
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    • 1977
  • The effect of humidity on the aging process of hydrous aluminum oxide prepared by the reaction of aluminum chloride and sodium bicarbonate solution at pH 7.8, which was then kept in various atmosphere under relative humidity at 37.deg. was observed by the measurements of acid consuming capacity, X-ray diffraction and IR absorption. The humidity was one of the important factors influencing the aging process of hydrous aluminum oxide during storage. The higer the humidity, the more was accelerated age, crystalize and loss in acid reactivity. Depending on the humidity, the aging product was different, especially, in the case of up to the relative humidity of 72%, it forming bayerite. On the other hand, the hydrous aluminum oxide aged below the relative humidity of 50% was still amorphous even after 120 days storage. When hydrous aluminum oxide was aged under higher humidity, definite IR absorption bands develop as the hydroxys become part of an ordered structure, and it showed their characteristic absorption band around 1630 and 1060 cm$^{-1}$.

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The changing of fitness and exercise guidelines for old adults (노인들의 체력 변화와 운동의 제언)

  • Yoon, Byung-Kon
    • Journal of Life Science
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    • v.17 no.6 s.86
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    • pp.867-872
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    • 2007
  • The aging is related to numerous changes in our body system which declines functional ability. The functional ability in advanced age can be evaluated by the 4 components of fitness (cardiorespiratory endurance, muscular strength and endurance, flexibility and body composition). The understanding and knowledge of changing 4 components of fitness and the role of exercise on the process of aging is of paramount importance. Despite exercise and physical activity have been shown to delay the process of aging, the exercise guidelines and recommendations for old adults are not well published. This review is to presents the age-related changes in each component of fitness and to present current guidelines and recommendations for exercise in older adults.

A Subjectivity Study on the Meaning of Aging for Elders (노인의 의미에 대한 주관성 연구)

  • Lee Keum-Jae;Park In-Sook;Kim Boon-Han
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.7 no.2
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    • pp.271-286
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    • 2000
  • This study is designed to investigate what elders think about the meaning of aging. We have used Q-methods to identify meaning of aging from elders, and developed self-referenced surveys to analyze characteristics In this study, we used a non-structured method to select Q sampling. From 183 Q populations, we selected 36 Q sampling. A total of 32 persons sixty-years or older were randomly selected for P samples, When the Q-sorting was complete, we interviewed the participants at both end of the extremes(agree or disagree), and documented their responses. We used PC QUANL to process the data and used principal component analysis for Q factor analysis. There were five subjective types for the meaning of aging by elders. Of the 32 P-samples of elders, 11 were identified as Type 1, 7 as Type 2, 2 as Type 3, 8 as Type 4, and 4 as Type 5. Type 1 : 'Matured elders' Elders wished the well being of their children, thought older persons should maintain good health, worried about becoming senile, and dependent God believing in life after death. Type 2 : 'Assertive-Rights' Elders categorized as Assertive-Rights insisted on their rights to life as a person. Type 2 elders characterized themselves as people who should keep themselves healthy, become weak and lack sexual desires, act selfish like a child, need to be protected, and be financially independent. Type 3 : 'Passive-Dependents' Elders characterize themselves as those who pray for their children's well being, worry about the children even after their death. and becoming senile. Type 4 : 'Hopeless' The 'Hopeless' type of elders characterized aging as a time to pray for their children, insignificant beings, thoughts were selfish and child-like, poor, worried about going senile, regret their life overall, and preferred to die than to live as an old person. Type 5 : 'Attached-Present' The 'Attached-Present' type of elders thought elderly characterized themselves as acting selfish and child-like, wiser, anxious, regret their life, stand aloof of greed and worldly things, being a model for the society, and deserving to be treated with filial respect. Thus far, Korean elders seemed to have a positive and negative meaning of aging due to the current changes in the society, value system, and family structures. The above five subjective meanings of aging confirm that we need to approach and nurse the elderly differently. Years of aging are a part of and a natural process of life with various physical, psychological, and sociological changes. Nurses need to assist elderly to find the positive meaning of their life by providing appropriate physical, psychological, and social support at an earlier stage in nursing. Based on this study, we could derive the following two implication from the perspectives of science of nursing to care for elders. 1) Based on the studies investigating the type of meaning of aging, we could develop tools to assist in nursing intervention programs for elderly. 2) Based on research on the meaning of aging for different developmental stages of life, we could develop a model for roles for different family members in nursing and caring for the elders.

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The Study on Aging (노화(老化)에 대한 연구(硏究) (황제내경(黃帝內經)을 중심으로))

  • Baek, Sang-Ryong
    • Journal of Korean Medical classics
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    • v.12 no.2
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    • pp.176-183
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    • 1999
  • Each life has its own properties that distinguish one another. With this property, Oriental medicine suggests original diagnosis and treament. Our process of aging shows typical outline of cycle, i. e. from one's birth to death. Understanding the life cycle of men gives us very good hint to predict one's state of health, possible diseases, characteristics of disease in each term of his/her life cycle. It's because body and mode of diseases change according to age. Aging starts when $\breve{U}$m Essence(陰精)-the essence one receive from parents-dries up or when Deficient Fire(虛火) soars. Parts that compose our body-bones, muscles, flesh, etc.-gradually weaken and worn out as they no longer get support from Yang-Ki(陽氣), In "Yellow Emperor's Classic", aging starts around one's forties when $\breve{U}$m Essence(陰精) is reduced to less than half. However, what is usually accepted is that women start aging from 49 and men 64, regarding significant geriatric disease. As it is mentioned, aging starts with exhaustion of $\breve{U}$m Essence(陰精) which results in soaring Deficient Fire. Main symptoms are weak mental state due to Sin(神) disorder, and weak physical state due to Spleen and Stomacn(脾胃) disorder. Main principle in treating and preventing diseases related to aging is preserving $\breve{U}$m Essence(陰精), as well as fortifying Ki and Blood(氣血). To do this, Lung(肺)-which collects $\breve{U}$m Essence(陰精), and Kidney(腎) stores-which stores $\breve{U}$m Essence(陰精).

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Shear Strength and Aging Characteristics in Solder Bumps for High Reliability Optical Module (고신뢰성 광모듈을 위한 솔더 범프의 전단강도와 시효 특성)

  • 유정희
    • Journal of Welding and Joining
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    • v.21 no.2
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    • pp.97-101
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    • 2003
  • The change of microstructures in the base metal during transient liquid phase bonding process of directionally Ni base superalloy, GID-111 was investigated. Bonds were fabricated using a series of holding times(0~7.2ks) at three different temperatures. The flip chip bonding utilizing self-aligning characteristic of solder becomes mandatory to meet tolerances for the optical device. In this paper, a parametric study of aging condition and pad size of samples was evaluated. A TiW/Cu/electroplated Cu UBM structure was selected and the samples were aging treated to analyze the effect of intermetallic compounds with the time variations. An FIB technique was applied to the preparation of samples for TEM observations. An FIB technique is very useful to prepare TEM thin foil specimens from the solder joint interface. After aging treatment, the tendency to decrease in shear strength was measured and the structure of the solder and the UBM was observed by using SEM, TEM and EDS. As a result, the shear strength was decreased of about 21% in the 100${\mu}{\textrm}{m}$ sample at 17$0^{\circ}C$ aging compared with the maximum shear strength of the sample with the same pad size. In the case of the 12$0^{\circ}C$ aging treatment, 18% of decrease in shear strength was measured at the 100${\mu}{\textrm}{m}$ pad size sample. An intermetallic compound of Cu6Sn5 and Cu3Sn were also observed through the TEM measurement by using.

Effect of PWHT on Variability of fatigue Crack Propagation Resitance in TIG Welded Al 6013-T4 Aluminum Alloy (TIG 용접된 Al6013-T4 알루미늄 합금에서 피로균열전파저항의 변동성에서의 PWHT의 영향)

  • Haryadi, Gunawan Dwi;Lee, Sang-Yeul;Kim, Seon-Jin
    • Journal of Power System Engineering
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    • v.15 no.6
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    • pp.73-80
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    • 2011
  • The experimental investigation focuses on an influence of artificial aging time in longitudinal butt welded Al 6013-T4 aluminum alloy on the fatigue crack growth resistance. The preferred welding processes for this alloy are frequently tungsten inert gas welding (TIG) process due to its comparatively easier applicability and better weldability than other gas metal arc welding. Fatigue crack growth tests were carried out on compact tension specimens (CT) in longitudinal butt TIG welded after T82 heat treatment was varied in three artificial aging times of 6 hours, 18 hours and 24 hours. Of the three artificial aging times, 24 hours of artificial aging time are offering better resistance against the growing fatigue cracks. The superior fatigue crack growth resistance preferred spatial variation of materials within each specimen in the Paris equation based on reliability theory and fatigue crack growth rate by crack length are found to be the reasons for superior fatigue resistance of 24 hours of artificial aging time was compared to other joints. The highest of crack propagation resistance occurs in artificial aging times of 24 hours due to the increase in grain size (fine grained microstructures).

Effect of Aging on the Interfacial Characteristics of ${Al_{18}}{B_4}{O_{33}}$/AS52 Mg Matrix Composite by Squeeze infiltration (용탕가압침투법으로 제조한 ${Al_{18}}{B_4}{O_{33}}$/AS52 Mg기 복합재료의 계면 특성에 미치는 시효의 영향)

  • Park, Yong-Ha;Park, Yong-Ho;Cho, Kyung-Mox;Park, Ik-Min
    • Journal of Korea Foundry Society
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    • v.28 no.6
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    • pp.268-272
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    • 2008
  • Interfacial characteristics of aluminum borate whisker reinforced AS52 matrix composite was investigated. Peak hardness of AS52 composite was obtained aging at $170^{\circ}C$ for 15h and the aging process was accelerated by the presence of the aluminium borate whisker. The MgO layer, which was the interfacial reaction product between the reinforcement and the Mg matrix, was produced with 20 nm thickness in as-cast condition. As the aging time increased, the thickness of the interfacial reaction layer increased to 50 nm in peak aged condition. The nano-indentation test results indicated that the strength of interface was improved by the aging but over-aging degraded the reinforcement and decreased the interfacial strength which resulted in the decrease of overall composite strength.