• Journal of Biosystems Engineering
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• 제36권3호
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• pp.163-170
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• 2011

Analysis of load on major parts of the tractor power drive line is critical for efficient and optimum design of a tractor. The purpose of this study was to evaluate severeness of the tractor PTO driving axle during rotary tillage operation. First, S-N (stress vs. number of cycle) curve of a PTO driving gear was obtained through the fatigue life test using a PTO dynamometer. Second, PTO severeness was evaluated during rotary tillage operation. Torque measurement system was constructed with strain-gauge sensors to measure torque of a PTO axle, an I/O interface to acquire the sensor signals, and an embedded system to calculate severeness. The severeness of PTO was analyzed using measured torque data during rotary tillage. In the PTO gear life fatigue test, breakage time and bending stress of the gear were measured by tooth widths and torque change during the fatigue life test. The S-N curve showed a good linear relationship between bending stress and number of cycle (life) with a coefficient of determination of 0.97. For PTO severenss evaluation, rotary tillage operations were conducted at two PTO rotational speeds (level-1, level-2) under different paddy and upland field sites with different soil conditions. Results of averaged relative severeness for PTO level-1 and PTO level-2 were 1.96 and 3.34, respectively, at paddy field sites, and they were 1.36 and 2.51, respectively, at upland field sites. The results showed that the PTO driving axle experienced more severe load during rotary tillage at paddy fields than at upland sites, and relative severeness was greater at the higher PTO rotational speed under all of the soil conditions.

• 드라이브 ㆍ 컨트롤
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• 제16권4호
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• pp.23-31
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• 2019

The purpose of this study was to evaluate the PTO severeness for an agricultural tractor during disk plow and rotary tillage. The PTO load measurement system was constructed with data acquisition and a PTO torquemeter. Field experiments were conducted at a combination of traveling speed (L3 Low, L3 High) and PTO speed (P1, P2). The load spectrum was generated using the rain-flow counting method, and the SWT method was used to consider the range and mean of the PTO load. The damage sum was calculated by applying a modified miner rule, which is a cumulative damage law. The relative severeness was expressed as the ratio of the lowest damage sum. Relative severeness was higher with the lower PTO gear stage, and higher driving gear stage and it was approximately 40-102 times higher for rotary tillage than disk plow tillage in the same gear stages. The relative severeness was 1010.12 in the rotary tillage under L3 High P1 based on the disk plow tillage under L3 Low P2.

• Journal of Biosystems Engineering
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• 제23권5호
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• pp.417-426
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• 1998

This study was intended to investigate the characteristics of loads acting on the transmission of agricultural tractors during plowing, rotavating and transporting operations. A survey was conducted to determine working speeds and transmission gears most frequently used for each operations. The transmission loads were measured at the input shaft of the transmission gear box during each operations. Time histories of the measured torque loads were converted into a load spectrum and analyzed with respect to the S-N curve of the shaft material to estimate the partial damages on the transmission. Finally, comparison of the relative damages and severeness of each operation was presented and discussed.

• Journal of Nutrition and Health
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• 제20권6호
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• pp.422-431
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• 1987

Dietary habits and serum lipid composition of 80 hospitalized patients with cerebrovascular disease (CVD) were compared to those of normal subjects. CVD patients were significantly higher in BP, serum cholesterol and triglyceride levels and low4r in HDL-choelsterol which resulted in the higher ratio of serum chol/HDL-chol than normal. Patients were also lower in the relative amount of HDL fraction by electrophoresis but were higher in LDL fraction and the ratio of LDL/HDL . In Korean, the high levels of serum chol, TG and LDL with low level of HDL as well as high BP could be one of the important causing factors of CVD. However, dietary habits of patients were not significantly different from those of normal . There is a possibility that patients might have controlled their dietary habits after they realized the severeness of disease.

• 동국한의학연구소논문집
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• 제1권
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• pp.161-191
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• 1992

The purpose of this study is how have the form and theory of the five element theory in the (黃帝內徑) by the investigation of the course of the course of the five element introduced the ancient oriental medicine from ancient oriental philosophy. The following results were obtained. 1. The five elements in (尙書) meaned the uses of water, fire, earth, wood, metal which were important in living. Because these had very important meaning in ancient political and economic society, emphasized to big law(洪範) 2. The five elements in (左傳) and (國語) mean the five uses too, and there are the phases of "five win metal"(火勝金) and "wather win fire"(水勝火), but these only meaned the physical interrelation. 3. In the five circulating factor theory made by Chu Yen(鄒衍) which have the attribute of the five elements, he more reasonably had argued human affairs like that a dynasty become different in step with the circulating five favors. There is the regular annual policy in the (呂氏春秋) which closely connected nature and human living, and attached the various colors, animals, visceras, flavors, sounds, the sexagenary cycle and so on to the five elements. 4. In the (春秋繁露) writed in fore-period of Han(漢) dynasty, the interactions of the five elements are concretely applicated to policy, Dong Jung Soe(童仲舒) had discrived the interactions of the five elements by Dong Lyu Sang Dong theory(同類相動說) and the misfortune theory(災異說), emphasized the sympathy of nature and human. Thought there is many content which are superstitious and contradictory, I concider which that affcted many effects in the formation of five element theory of oriental medicine. In the (淮南子) the order of matters were explained by the five element theory too, as the interrelations of the five elements were explained by the sexagenary ctcle, I assume that the bud of O-Un theory(五運理論). And there was not founded the fullscale intriduction of the five element theory in the Ma Wang Tye(馬王堆) excavated finds, the Mu Yyi medical writings formed the dynasty(武威漢代醫簡) and the documents about Pyun Jak(偏鵲) and Sun U Ie(淳于意). 5. The application of the five element theory in the (Whang Di Nei Qing) (黃帝內徑) is devided into the attachement to the five elements, the interelations of the five elments, and Un Gi theery(運氣論). In the attachment to the five elemeant theory, it made the attachment of the five viseras of (今文尙書) party a standard and attached the sections of a human body, the whole internal organs of sense, the five colors, the five flavors and the five sounds and so on to the five elements. It put to use by means of the apllivation of the interrelation of the five elements in the transferations of the diseases and the relative severeness of a disease in step with change of time and season. Un Gi theory(運氣論) which synthesized by the attachment to the five elements, the inter-relations of the five elements and the climate which observerd from ancient times systematically argued the effects of weather to human. 6. The application of the five elements theory in (黃帝內徑) have the significant what had get rid of irrational factors like that the emotion and action of human could to influense the weather, what had been formes more rational thingking by the obesrvation of human and nature. It is required more reserches about the possibility of the formation of the doctrinal faction bt the geographical effect of the Yon, Je(燕,薺) region, the application of the five element theory in other ancient medical books and the relationship of the five element theory and Yin Yang(陰陽)