• Title/Summary/Keyword: Environment Vibration

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Effects of the Vibration Stress on Cortisol and Hematological Characteristics in Soft-shelled Turtle, Pelodiscus sinensis (진동 스트레스에 따른 자라, Pelodiscus sinensis의 코티졸 및 혈액학적 특성)

  • Hur, Jun-Wook;Lee, Jeong-Yeol;Chang, Young-Jin;Bai, Sung-Chul;Park, In-Seok
    • Development and Reproduction
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    • v.13 no.1
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    • pp.43-49
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    • 2009
  • We examined the effects of the vibration stress on cortisol secretion and hematological characteristics in soft-shelled turtle, Pelodiscus sinensis. For the stressed group vibration of $45{\sim}78 dB(V)$ from electric vibrator applied for 30 min with 2-h intervals during daytime ($08:00{\sim}18:00$) up to 28 days. Using the blood samples collected from ten turtles held once a week after vibration stress, we measured hematocrit, hemoglobin, red blood cells, cortisol, glucose, lactic acid, osmolality, $Na^+,\;K^+,\;Cl^-$, aspartate aminotransferase (AST), and alanine aminotransferase (ALT). The results have showed that P. sinensis received vibration stress exhibit the 'typical' stress-induced physiological responses (cortisol, glucose, lactic acid, osmolality, ions, hematocrit and hemoglobin) induced by vibration stress. Our data suggested that chronic vibration stress caused substantial stress in the animal, and in particular, the persisting elevated levels of AST and ALT would be highly correlated with the adverse effects of the stress. The high hematological characteristics during entire experimental period showed that the P. sinensis could not adapt to chronic stimuli provoked by vibration stress.

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On-orbit Micro-vibration Isolation Performance Verification for Spaceborne Cryocooler Passive Vibration Isolator Using SMA Mesh Washer (SMA 메쉬 와셔를 적용한 우주용 냉각기 수동형 진동절연기의 궤도 미소진동 절연성능 검증)

  • Kwon, Seong-Cheol;Jeon, Su-Hyeon;Oh, Hyun-Ung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.25 no.1
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    • pp.24-32
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    • 2015
  • Pulse tube-type spaceborne cryocooler is widely used to cool down the infrared sensor of observation satellites. However, such cryocooler also generates micro-vibration which is the one of main sources to seriously affect the image quality during its on-orbit operation. Therefore, to comply with the mission requirement of high resolution observation satellite, additional technical efforts have been required. In this study, we proposed a spaceborne cryocooler passive vibration isolator using SMA mesh washer, which guarantees the structural safety of both the micro-vibration disturbance source and itself under harsh launch vibration loads without an additional holding mechanism and the micro-vibration isolation performance on orbit environment. To verify the micro-vibration isolation performance of the proposed vibration isolator, we performed the micro-vibration isolation measurement test using the dedicated micro-vibration measurement device proposed in this study.

A Study on the Determination of Vibration Criteria for Vibration Sensitive Equipments Using Impact Test (충격시험을 이용한 고정밀장비의 진동허용규제치 결정기법에 관한 연구)

  • 이홍기;박해동;김두훈;김사수
    • Journal of KSNVE
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    • v.7 no.2
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    • pp.247-254
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    • 1997
  • In the case of a precision equipment, it requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga class semiconductor wafers. This high technology equipments require very strict environmental vibration standard in proportion to the accuracy of the manufacturing, inspecting devices. The vibration criteria are usually obtained either by the real vibration exciting test on the equipment or by the analytical calculation. This paper proposes a new method to solve this problem at a time. The permissible vibration level to a precision equipment can be easily obtained by analyzing a process of Frequency Response Function. This paper also demonstrates its effectiveness by applying the proposed method to finding the vibration criteria of a Computer Hard Disk Driver by Impact Test.

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Introduction and activities of ISO/TC 108/SC 6 (ISO/TC 108/SC 6 소개 및 최근 활동)

  • Kim, Nag In
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.04a
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    • pp.545-547
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    • 2014
  • The scope of ISO/TC 108/SC 6, revised in accordance with Doc. ISO/TC 108/SC 6 N 35, September 1997, is as follows: Standardization in the field of vibration and shock generating systems, for test purposes (including environment, seismic and dynamic testing, calibration and diagnostics) as well as auxiliary equipment and instrumentation normally associated with it. Vibration and shock generating systems as an object of standardization within ISO/TC 108/SC 6 are only those systems that are used during vibration/shock testing to determine properties of a specimen. Vibration and shock systems being used in such processes as transportation, milling, compacting, metal working, etc., as parts of vibration control systems or household appliances and in health services, are not covered by ISO/TC 108/SC 6.

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A Study on the Structural Dynamic Design for Sub-micro Vibration Control in High Class Semiconductor Factor by Semi-Empirical Method (준 경험기법을 이용한 고집적 반도체공장의 미진동 제어를 위한 구조물의 동적설계에 관한 연구)

  • 이홍기;백재호;원영재;박해동;김두훈
    • Journal of KSNVE
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    • v.9 no.6
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    • pp.1227-1233
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    • 1999
  • Modern technology depends on the reliability of extremely high technology equipments. In the production of semiconductor wafer, optical and electron microscopes, ion-beam, laser device must maintain their alignments within a nanometer. This equipment requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga and tera class semiconductor wafers. This high technology equipments require very strict environmental vibration standard, vibration criteria, in proportion to the accuracy of the manufacturing, inspecting devices. This paper deals with the structural dynamic design in high class semiconductor factory in order to be satisfied more strict vibration criteria for high sensitive equipment.

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A Study on the Mismatch of Time and Frequency Domain for Vibration Criteria of Sensitive Equipment (고정밀 장비의 진동허용규제치에 대한 시간 및 주파수 영역에서 나타나는 불일치 문제에 관한 연구)

  • 이홍기;김강부;전종균;백재호
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.11b
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    • pp.1376-1383
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    • 2001
  • Modem technology depends on the reliability of extremely high technology equipments. In the production of semiconductor wafer, optical and electron microscopes, ion-beam, laser device must maintain their alignments within a sub-micrometer. This equipment requires a vibration free environment to provide its proper function. Especially, lithography and inspection devices, which have sub-nanometer class high accuracy and resolution, have come to necessity for producing more improved giga and tera class semiconductor wafers. This high technology equipments require very strict environmental vibration standard, vibration criteria, in proportion to the accuracy of the manufacturing, inspecting devices. The vibration criteria of high sensitive equipment should be represented in the form of 'exactness' and 'accuracy', because this is used as basic data for the design of building structure and structural dynamics of equipment. This paper deals with the properties of time and frequency domain in order to obtain more improved vibration criteria for high sensitive equipment.

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Studies on the Nutrition under Abnormal Environment(I) -Nutrition under Vibration- (이상환경하(異常環境下)의 영양문제(營養問題) 연구(硏究)(제1보) -진동하(振動下)의 영양문제(營養問題)-)

  • Yu, Jong-Yull
    • Journal of Nutrition and Health
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    • v.4 no.4
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    • pp.15-23
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    • 1971
  • On the assumption that the supplementation of certain nutrients or foods to the rice diet (low protein, low fat, and low vitamins) may decrease, to some extent, the degree of suffering from abnormal environments, such as vibration, noises, gases, dusts, smog etc. a series of experiments were started. As the first report the nutrition under vibration was studied in this experiment. Sixty (60) young growing male rats weighing about 65 grams were used, grouping to five (5) groups, twelve (12) rats each group. They were fed on the following five (5) experimental diets: rice diet (basal diet), rice diet+casein, rice diet+vitamins, rice $diet+{\alpha}-tocopherol$, and rice diet+ginseng powder (see the tables 1 and 2) for the period of 14 weeks experiment. During the experiment period the half number of the rats of each group were exposed to the three (3) hours vibration every day. The protective effect of each diet against the vibration may be summarized as follows. 1. The growth of rice diet group was impaired significantly under vibration, However, those of other groups (protein-supplemented, vitamin-supplemented, ${\alpha}-tocopherol-supplemented$ and ginseng-supplemented groups) were impaired much less compared with rice diet group. 2. The feed efficiency of the rice diet group was decreased significantly under vibration. It is estimated that the biological availability of nutrients was impaired under this environment. On the other hand, the feed efficiencies of protein supplemented, of vitamin supplemented, and of ginseng supplemented groups were not decreased under vibration, statistically. 3. There is tendency that the food spillages of vibration groups are higher than those of non-vibration groups. Especially it seems true in the case of rice diet group. The food spillage may be, to some extent, related with mental nervousness of animals. From the point that the food spillage of ginseng supplemented group is significantly lower than those of other groups it is thought ginseng acts some good role in protecting nervous system from suffering from vibration. 4. In all groups except protein supplemented group, liver fat of vibration group tends to be higher than that of non-vibration group. 5. It shows that, in general, the serum alkaline phosphatase activity of the vibration group is significantly higher than that of the non-vibration group. It seems that there may be, to some extent, corelation between the amount of liver fat and serum alkaline phosphatase activity. 6. There is tendency that, in rice diet group, the organs of vibration group are smaller than those of non-vibration group, especially lung is so. It is thought that this may be due to the poor growth of whole body size in vibration group.

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A Study on Main Engine X-mode Vibration Phenomenon due to 2nd Node Torsional Vibration of the Marine Propulsion System (선박 추진축계의 2절 비틀림진동에 기인한 주기관 X-모드 진동 현상의 연구)

  • Lee, Donchool;Kim, Junseong;Kim, Jinhee
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.23 no.9
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    • pp.806-813
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    • 2013
  • For the past years, higher power rating 2 stroke super long stroke diesel engines having more than 8 cylinders and larger cylinder bore are installed mainly on very large containerships to save on fuel consumption. However, these engines are prone to X-mode vibration due to 2nd node torsional vibration or the X-type moment, particularly because of the increase in total length and height. Recently, cases of excessive X-mode vibration often occurred on engine's major components. This vibration is manifested also as secondary vibration causing failure in engine-mount large structures. This study investigated the excitations caused by the 2nd node propulsion shafting torsional vibration that influence X-mode vibration of the main engine and practical countermeasures are proposed. An 8RT-flex82T 8 cylinder engine and 11S90ME-C 11 cylinder engine for a container ship was used as research model.

Indoor Noise Analysis of Naval Combat Service Support Boat (전투근무지원정 격실의 실내 소음 분석)

  • Park, Mi-You;Han, Hyung-Suk;Cho, Heung-Gi
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2011.04a
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    • pp.91-96
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    • 2011
  • The ship working environment of combat service support boat is very inferior to the ground working environment. For this reason, the crew of a combat service support boat suffer from an occupational disease such as hardness of hearing. Owing to its small size and low status, the improvement of its working and residential environment is occasionally ignored and its indoor noise was not fully investigated. In this study, for improving its residential environment indoor, the indoor noise of its shipboard compartments was analysed.

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Indoor Noise Analysis of Naval Combat Service Support Boat (전투근무지원정 격실의 실내소음 분석)

  • Park, Mi-You;Han, Hyung-Suk;Cho, Heung-Gi
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.21 no.7
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    • pp.609-614
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    • 2011
  • The ship working environment of combat service support boat is much inferior to the ground working environment. For this reason, the crew of a combat service support boat suffer from an occupational disease such as hardness of hearing. Owing to its small size and low status, the improvement of its working and residential environment was occasionally ignored and its indoor noise was not fully investigated. In this study, for improving its residential environment indoor, the indoor noise of its shipboard compartments was analysed. These studies define the indoor noise level of combat service support boat is very high and some of indoor noise is exceeded the criteria for ship noise. Compared with marine police vessels, the indoor noise levels of marine police vessels are higher than the level of combat service support boat.