• Journal of Drive and Control
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• v.20 no.3
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• pp.9-14
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• 2023

In this paper, the selection of a reliable accelerated life test code for a 2-ton forklift was accomplished by choosing the driving resistance coefficient failure-free test time based on a 10,000-hour B₁₀ life. The overall life and average equivalent load of the vehicle were then calculated based on actual driving test conditions using the selected driving resistance coefficient. The gear train's accelerated life test code was selected by adjusting the equivalent load to a torque and rotation speed that did not exceed 125%(about 75HP) of the vehicle rated power. The safety of the test standards was validated by conducting an actual accelerated life test utilizing the proposed test method in this study and comparing the test result with the corresponding theoretical value. It is anticipated that the reliability of the accelerated life test in this paper will be enhanced, by incorporating actual driving performance data collected directly from the forklift and adjusting the conditions used in developing the accelerated life test code.

• Korean Journal of Medicinal Crop Science
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• v.18 no.4
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• pp.273-279
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• 2010

The study result survey platycodon cultivation regions of Jinju(2), Sacheon(4), Hapcheon(3), Haman(3), and Sancheong(3) of Gyongnam regarding chemical properties of soil, inorganic nitrogen phosphorus by type of composition is as follows: pH and EC value were highest where platycodon cultivated for under 3 years in soils. Content of O.M equal to or less than 25 mg $kg^{-1}$, the average value for platycodoncultivation in korea. Content of exchangeable calcium in soils were 12, 14 $cmol^+kg^{-1}$ in Hapcheon and Haman regions where platycodon was cultivated for two years which is 2~3 time higher level compared with the average upland soil of korea. Water solution boron confirmed approximated level of 3.0 mg $kg^{-1}$ in all survey regions, and the finding is about five times higher than average upland soil of korea which is 0.5 mg $kg^{-1}$. In the case of nitrogen, a significant difference was found depending on cultivation regions and continuous culture. Content of nitrogen in soils were difference according to cultivation area and continuous culture. The composition ratio according to the type of inorganic phosphorus showed the highest in order of Al-P > Ca-P > Fe-P > Saloid-P in all survey regions except for Hapcheon (five, seven years cultivated soils). The correlation showed high significance between available phosphate and inorganic phosphorus.

• Journal of Forest and Environmental Science
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• v.30 no.3
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• pp.301-306
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• 2014

A study was carried out to identify the life cycle of Adoxophyes orana (Lepidoptera: Tortrididae) that inflicts tea tree leaves in Korea and selected three ecofriendly pesticides (Common name for commercial: Essential oil, Nemacatch, and Wormstop in Korean Farmers' Market) of A. orana for pest control. A. orana appeared to follow four life cycle phases a year; each presenting varying developmental periods dependent on seasonal and environmental factors. The fecundity of A. orana female was $24.6{\pm}4.10$ for $1^{st}$, $36.7{\pm}12.77$ for$ 2^{nd}$, and $27.9{\pm}4.22$ for $3^{rd}$ phase during 2011, while it was $65.0{\pm}32.72$, $49.7{\pm}30.27$, $63.8{\pm}27.22$ for corresponding phases during 2012. The average longevity of adult A. orana was 7.72 days. The average number of eggs deposited by each female in this study group was 44.62 with an average of 2.47. In three selected ecofriendly pesticides, the mortality of A. orana on treating with the Essential oil [The essential oil of Chamaecyparis obtuse (100%)] and Nemacatch [Azadirachtin 800-900 ppm (75%)] were 36.67% and 43.33% after 3 days and were 48.30% and 56.67% after 7days, respectively. Besides, the mortality of A. orana on treating with Wormstop [Azadirachtin 500 ppm (5%) and Salannin+Liminoids (95%)] was 61.67% and 78.33% after 3 and 7 days, respectively. Therefore, the application of Wormstop was the most useful to control the diseases caused by A. orana.

• Journal of Korean society of Dental Hygiene
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• v.21 no.3
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• pp.311-318
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• 2021

Objectives: The purpose of this study was to understand the level and patterns of college adjustment, major satisfaction, academic engagement, and attention deficit hyperactivity disorder (ADHD). This study examined the factors influencing adaptation to college life. Methods: This study was approved by the institutional review board of 00 university. We analyzed 166 survey data responses collected by distributing questionnaires from June 1 to July 2, 2020. Statistical product and service solutions version 23.0 was used for statistical analyses. The data were presented as frequencies and percentages or means and standard deviations, and pearson correlation analysis and multiple regression analysis were performed. Results: There was a significant difference in the average score of major satisfaction according to the type of college (university) and grades. For college adjustment, there was a significant difference in the average score according to major grades. Academic engagement showed a significant difference in the average score according to the college type and grade. Major satisfaction, college adjustment, and academic motivation showed significant positive correlations among the variables, whereas ADHD, major satisfaction, and college adjustment showed a significant negative correlation. Multiple regression analysis revealed that major satisfaction (p<0.001) and academic motivation (p<0.001) were factors affecting college adjustment (p<0.05). Conclusions: It is necessary to develop and apply specific and systematic adaptation programs to improve the understanding, control, and guidance methods for college students and to promote human relations, such as school life and social life.

• Animal Bioscience
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• v.36 no.2
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• pp.322-332
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• 2023

Objective: We determined the impact of maintaining pasture-based dairy cows and calves together over 100 days on cow milk production, cow and calf behavior, and calf liveweight and carcass quality. Methods: Six Holstein-Friesian cows and their male calves were monitored for 106±8.6 days. Cows were temporarily separated twice a day for milking with calves remaining in the paddock. Cow and calf behaviors were recorded via scan sampling at 6 different timepoints, for the first 7 days and twice a week thereafter. Calves were weighed weekly and immediately processed for meat quality and rumen development analysis at 106±8.6 days. Daily cow milk yields were collected from enrollment until 109±8.6 days (3 days post-weaning). Results: The average daily gain of calves was 1.4±0.73 kg/d, with an average carcass dressing percentage of 59%. Calves had the greatest frequency of observed close proximity to cow and suckling in the first two weeks and decreased with experiment duration. During separation for milking, cow vocalizations and attempts to return to their calf decreased over time. Reticulorumen weight was on target for calf age, but as a proportion of total stomach weight was lower than industry averages of calves the same age due to the larger abomasum. Cows produced an average of 12±7.6 kg of milk yield per day over the 3-days before the calves were weaned and increased to mean of 31±8.3 kg/d the 3 days after weaning, indicating a consumption of close to 20 kg per calf per day. Conclusion: The impact of a pasture-based cow-calf rearing system on cow and calf behavior and the potential for high levels of calf liveweight gain when provided ad-libitum milk and feed were determined. Further research is required to determine the practicality of replicating such systems with large herds and impact on reared calves post-weaning.

• The Korean Journal of Pain
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• v.36 no.2
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• pp.253-267
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• 2023

Background: Cancer-induced bone pain (CIBP) is considered to have both nociceptive and neuropathic components. However, the prevalence, risk factors, and impact of the neuropathic components are yet poorly understood. Methods: We estimate the prevalence of neuropathic pain (NP) features in patients with CIBP at a tertiary care pain clinic setting using the Douleur Neuropathique 4 questionnaire and evaluate their associated factors and their impact after 4 weeks of treatment using the Brief Pain Inventory questionnaire and the Edmonton Symptom Assessment System. Results: A total of 133 patients were recruited. The estimated prevalence of NP was 30.8% (95% confidence interval: 23.6%-39.1%). Initially, the patients with NP had significantly higher average pain scores (6.00 vs. 5.05, P = 0.006), higher total interference scores (5.84 vs. 4.89, P = 0.033), and symptom distress scores (35.88 vs. 26.52, P = 0.002). After 4 weeks of treatment, patients in both groups reported significantly decreased pain intensity and improved quality of life. However, the patients with NP still reported significantly higher average pain (4.61 vs. 3.58, P = 0.048), trending toward higher total interference scores (3.52 vs. 2.99, P = 0.426), and symptom distress scores (23.30 vs. 20.77, P = 0.524). From multivariate analysis, the independent risk factors for NP were younger age, pain in the extremities, and higher average pain scores. Conclusions: NP are common in patients with CIBP. These conditions negatively affect pain intensity and the patient's quality of life before and after treatment.

• Animal Bioscience
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• v.36 no.10
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• pp.1584-1595
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• 2023

Objective: This study was conducted to evaluate the effect of a low-protein diet on growth performance, carcass traits, nutrient digestibility, blood profiles, and odor emissions in growing-finishing pigs. Methods: A total of 126 crossbred pigs ([Yorkshire×Landrace]×Duroc) with an average body weight (BW) of 38.56±0.53 kg were used for a 14-week feeding trial. Experimental pigs were allotted to one of 6 treatments in 3 replicates of 7 pigs per pen in a randomized complete block design. Pigs were fed each treatment diet with different levels of crude protein (CP). Phase 1 (early growing): 14%, 15%, 16%, 17%, 18%, 19%; phase 2 (late growing): 13%, 14%, 15%, 16%, 17%, 18%; phase 3 (early finishing): 12%, 13%, 14%, 15%, 16%, 17%; phase 4 (late finishing): 11%, 12%, 13%, 14%, 15%, 16%. All experimental diets in each phase were contained the same concentration of lysine (Lys), methionine (Met), threonine (Thr), and tryptophan (Trp). Results: Over the entire experimental period, there was no significant difference in BW, average daily feed intake, and gain-to-feed ratio among all treatments (p>0.05), but a quadratic effect (p = 0.04) was observed in average daily gain (ADG) during the late finishing phase with higher ADG in Group D. Blood urea nitrogen concentration linearly increased with an increase in dietary CP levels (p<0.01). Regarding nutrient digestibility, excreted nitrogen in urine and feces and nitrogen retention linearly increased as the CP level increased (p<0.01). A linear effect was observed with increasing CP levels in amines, ammonia, and hydrogen sulfide in odor emissions (p<0.01). No significant effects were observed in the measurements of carcass traits and meat characteristics (p>0.05). Conclusion: In phase feeding, reducing the CP level to 14% in early-growing pigs, 13% in late-growing pigs, 12% in early-finishing pigs, and 11% in late-finishing pigs is recommended.

• Journal of Agricultural Extension & Community Development
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• v.19 no.2
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• pp.381-408
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• 2012

The subjects of the research were 275 aged care nurses working in Gyeonggi regions. The analysis result showed: job satisfaction in overall situation was 2.87 on a 5 point scale, indicating the level of job satisfaction was lower than average: the quality of life was 2.97, as with job satisfaction, also low. On the other hand, the research outcomes to discern if it affects the lower level of the quality of life, it was found that variables affecting psychological health include job, pay, co-workers, organization, changing an occupation/job; Social environment include job, pay, and promotion (reward), The maintenance of social relations, pay, promotion(reward) and co-workers, changing an occupation/job; variables affecting physical health include job, pay, promotion(reward), changing an occupation/job; The research outcomes confirm that the job satisfaction of aged visit care workers is an important factor affecting their quality of life.

• Journal of Korean Institute of Industrial Engineers
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• v.14 no.1
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• pp.103-117
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• 1988

Replacement demand plays an important role to forecast the total demand of durable goods, while most of the diffusion models deal with only adoption data, namely initial purchase demand. This paper presents replacement demand forecasting models incorporating repurchase rate, multi-ownership, and dynamic product life to complement the existing diffusion models. The performance of replacement demand forecasting models are analyzed and practical guidelines for the application of the models are suggested when life distribution data or adoption data are not available.

• Journal of Biosystems Engineering
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• v.34 no.5
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• pp.325-330
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• 2009

This study was performed to develop accelerated life test methods for agricultural tractor transmission receiving variable load. To acquire parameters for calculation of accelerated life test, endurance tests were performed under different torque conditions. Test results showed that the shape factor of Weibull distribution was 1.5 and fatigue damage exponent was 5.4. The calculated test time was 5,877 hours under the conditions of average life (MTBF) 3,000 hours and 90% reliability for one test sample. According to the linear cumulative damage rule, test time could be reduced using increased test load. Test time could be reduced by 252 hours when 1.2 times of the rated load compared with 0.67 times of the rated equivalent load calculated by load spectrum of the agricultural tractor. Calculated acceleration coefficient was 23.3.