• Journal of agriculture & life science
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• v.45 no.2
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• pp.61-67
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• 2011

To provide basic data for variety improvement of chestnut cultivated in southern Korea, nut characteristics were investigated during 2008-2010. The number of burr by variety ranged from 37.7 in Kwangjujoyul to 183 in Juok. There were significant differences among variety in number of nuts per burr, and Idea had the least number of nuts per burr (1.2), while Sandae and Kwangeun had the largest (2.0). Nut weight also showed a distinct difference among variety, and Kwangdeok had the heaviest, while Kwangjujoyul had the lightest nut weight. Changbanggamyul showed the highest healthy nut rate of 89.9%, and Kunumi, Arima, Tsukuba, Kwangeun, and Pyeonggi had the rate of healthy nut of more than 80%. Sinyipyeong and Isseumo showed the high rate of rot nuts of 10.8 and 16.8%, which was needed to give attention to nut storage. Split pericarp percentage ranged from 0% in Changbanggamyul to 20.6% in Saeil, and that was above 15% in Sandae, Riheiguri, Juok, Kwangdeok but Kunumi, Arima, Tsukuba, Manseong, Changbanggamyul, Chuckpabyunii, Isseumo had the split pericarp percentage of less than 3%.

• Journal of Korean Home Economics Education Association
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• v.33 no.4
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• pp.103-117
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• 2021

Nuts are cholesterol free with high poly-unsaturated fatty acids(PUFA) and have lower intakes of sodium than non-consumers, and thus they can decrease blood pressure. Hypertension is a common primary diagnosis in Korea. Because of extending exposure to 24-hour raised blood pressure and heart rate hypertension is likely to be caused by prolonged short sleep durations. This study examined the relationship between nut consumption and hypertension according to sleep duration among Korean adult. Based on data from the 2010-2016 Korea National Health and Nutrition Examination Survey(KNHANES), the final analytic sample(n=25,359) was used for current analysis. The dietary intake was assessed through a 24-hour recall method. Associations of nut consumption with sleep duration and hypertension were determined using multiple logistic regression with odds ratio(95% CI). All the analyses were carried out in SAS version 9.4, and the significance level was set at p<0.05. With increasing nut intake, the prevalence of hypertension significantly decreased(p for trend=0.02). After controlling for sleep duration, the nut consumption showed significant association with the prevalence of hypertension when sleep duration was 6 to 6.9 h per day(p for trend=0.03) or 7 to 7.9 h per day(p for trend=0.03). In conclusion, dietary total nut intake was found to be significantly associated with the prevalence of hypertension.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.4
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• pp.105-114
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• 2012

Soil moisture plays a pivotal role in hydrological processes, especially in the forest which covers more than 64% of the national land. Soil moisture was monitored to analyze soil moisture change characteristics in terms of time and soil layers in this study. 2 Years soil moisture change data was obtained from the experimental nut pine forest and statistical analysis including auto-correlation and cross-corelation among soil moisture data from different soil layers was conducted. Using the monitored soil moisture data, a relationship between soil moisture change and precipitation was analyzed and seasonal soil moisture change characteristics were analyzed. From the result of inter-relationships among soil layers in terms of season and time lag, soil moisture change characteristics in the nut pine forest were upper soil layers were much sensitive than lowers, and seasonal variation if soil moisture for upper soil layers were bigger than lowers showing low correlation with precipitation in winter and spring due to freezing and snowfalls.

• Transactions of Materials Processing
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• v.27 no.2
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• pp.81-86
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• 2018

In the cold forming process, it is not easy to fabricate a asymmetric type nut, due to the difficulty in the exact prediction of metal-flow. As we have identified, in that case, it often results in the various forging defects such as burrs, and an incomplete shape, as well as other problems because of this issue. In the current study, we introduce the development of an unparalleled shape Weld Nut by using a forging analysis tool (AFDEX). For the multi-forming machine, the optimized shapes of each intermediate product (step product) could be found by the use of a model for the prediction and analysis of various types, sizes and heights. Chiefly, forging tools were prepared based on the simulation results and an unparalleled shape could be prepared at one time without any burrs, incomplete shape and size.

• Journal of Korean Society of Forest Science
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• v.98 no.4
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• pp.504-511
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• 2009

This study to understand the production cost of cultivation in chestnut tree (Castanea spp.) as a result of a survey conducted of 227 farmers is as follows. In full-time farmer, average cultivation area was 5.5 hectares and average chestnut production was 1.6 tons per hectare. In chestnut sale type, more than 73% of total production was sold by Nong-hyup (7an agricultural cooperative association) and intermediaries, and also proportion of nut size grade was 18% in special-large nut, following 49% in large nut, 25% in middle nut and 8% in small nut. There was considerable difference among cultivated regions in gross income, whereas total average gross income was 2,103 thousand KRW per hectare and 66.4% of it was used in management expenses. Finally the chestnut cultivated farmers have a yearly income of 706 thousands KRW (net income rate 33.6%). As peculiarity of regional production cost, a low tree farm in height and a labor intensive growing helped the improved quality of the chestnut so, on average, 2,161 thousand KRW per hectare of the income of the Chungnam was raised. However caused by an old-age of chestnut trees, there was a little input to management expenses and it resulted in low productivity in the Jeonnam and the Gyeongnam.

• Transactions of Materials Processing
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• v.29 no.3
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• pp.157-162
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• 2020

Blind rivet nuts are increasingly used in automotive for the joining of sheets. Their application, however, requires appropriate design guides to prevent catastrophic events arising from the failure of joints. In this study, the shaft shape of a frequently used M8 blind rivet nut is optimized based on 3D numerical analysis of the blind rivet nut considering the characteristics of thread. The thread needs to be modeled to suitably consider the fastening of the M8 bolt after the crimping process. FE analysis showed that while the friction in the contact between crimp flange and plate has no significant effect on the crimp geometry, shaft thickness (t) and shaft height (h) are the most significant design variables. The parameter study including various combinations of t and h reveals that they affect the gap (the distance between the crimped flange and the plate that develops through riveting) and the load acting on the plate. The gap is an indicator of the tightening force. It is found that t is inversely proportional to the gap, and proportional to the load, whereas h is proportional to the gap and inversely proportional to the load. Based on our FE analysis results, we propose the range 0.062 < t/h < 0.1 to ensure sufficient fastening (high clamping load, small gap) of the M8 blind rivet nut. The design guide for determining the t/h ratio proposed in this study can be used for general quantitative analysis of the size and the t/h ratio of blind rivet nuts.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2005.11a
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• pp.72-73
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• 2005

This study was carried out to investigate the effects of extracts supplements of pine nut cone on the broiler performance and the cholesterol content, the lipid oxidation of serum and meat of broilers. The control group was fed a common basal diet without antibiotics and the treatment group were fed a common basal diet with extracts of pine nut cone of 500ppm(T1), illite 1% +extracts of pine nut cone of 500ppm(T2), pine nut cone powder of 2.5%(T3) for 5 weeks. The weight gain and the feed intake were significantly higher treatment than control. The cholesterol content of serum was significantly decreased in T1, T2 group. The breast was also significantly decreased in T1, T2 group. The thigh was not different among treatment, but the cholesterol content of serum was significantly lower in T1, T2 treatment than control. TBARS of the brest and the thigh showed significantly lower than control. POV of the brest and the thigh showed different among treatment, but there were no correlations among treatment.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.820-825
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• 2007

A ballscrew-linear motion(LM) guide is well-described by its name: it is a LM guide that runs by ballscrew. It consists of LM rail, LM block, end plate, screw, nut and bearing balls. The ballscrew-LM guide has many advantages compared with conventional LM guide. The high efficiency achieved with rolling contact devices permits the employment of antibacklash methods. The balls provide the only physical contact between nut rail and block and ball screw and nut replacing the sliding friction with a rolling motion. The life of the ballscrew-LM is determinated by the balls. The objective of this paper is to introduce the design of the ballscrew-LM with the safety working load.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.05a
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• pp.197-200
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• 2001

In the multi-stage former, manufacture of hexagonal fitting nut was generated in a defective products about $70{\~}80\%$. Defective products reduced in a product stiffness and increased a product cost. Defects for manufacturing hexagonal fitting nut caused in a increase of ductile fracture value. So in the study, a preform designed to reduce ductile fracture value and designed preform verified through the finite element simulation. In conclusion, Ductile fracture value reduced if A round dimension of preform reduced and a part of opposition angle contributed in Plenty a volume.

• Journal of Electrical Engineering and Technology
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• v.9 no.6
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• pp.2162-2167
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• 2014

Robots are widely used in various automation processes in industrial applications. Traditionally, it operated under fixed condition by teaching operating positions. Recently, diverse 2D/3D sensors are used together with robot to give more flexibility in operation. In this paper, we deal with automatic manipulation of tie rod in automotive production line. Sensor system consisted of a camera and slit laser is used for the acquisition of 3D information and it is used attached on the robot. Nut runner is used for the manipulation of stop nut and adjust bolt on the tie rod. Detailed procedures for the automatic manipulation of tie rod are presented. In the presented approach, we effectively use 3D information in whole procedure such as computing distance to the tie rod, rotation angle of bolt and nut. Experimental results show the feasibility of the proposed algorithm.