• Transactions of Materials Processing
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• v.32 no.5
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• pp.239-246
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• 2023

To reduce the forming load due to the temperature drop, during the hot forging process, a reheating hot forging process design is required that to repeat heating and forging. However, if the critical strain required for recrystallization is not induced during forging and grain growth becomes dominant due to the reduction in dislocation density due to repeated heating, the mechanical properties may deteriorate. Therefore, in this study, Inconel 706 alloy was applied, and the grain refinement behavior was comparatively analyzed according to the number of reheating times and effective strain during reheating hot forging process. Reheating was carried out with a total compression rate of 40% up to 4 times. The Inconel 706 compression test specimens heated once showed finer grains as the effective strain increased due to the dynamic recrystallization phenomenon. However, as the number of heating increases, grain refinement was observed even in a low effective strain distribution of 0.43 due to static recrystallization during reheating. Moreover, grain growth occurs at a relatively low effective strain of 0.43 when the number of reheating is four or more. Therefore, it was effective to apply an effective strain of 0.43 or more during hot forging to Inconel 706 in order to induce crystallization through grain refinement and improve the properties of forged products. In addition, we could notice that up to three reheating times condition was appropriate to prevent grain growth and maintain fine grain size.

• Journal of Platform Technology
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• v.11 no.4
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• pp.62-70
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• 2023

This research is one of a series of studies to develop a system to help agricultural producers and sellers determine when and how much to ship products to the wholesale market to maximize their profit. The purpose of this research is to incorporate the time-varying quality change effect, which was not used in the previous agricultural and marine product shipping model. The researchers developed four models to measure the quality change effect: quality declining steadily over time, quality declining rapidly at first and then slowly, quality declining first slowly and then rapidly, and quality rising over time and then decreasing again. According to the results of an empirical analysis of the effect of each model's quality change effect on shipments for apples traded in the Garak Wholesale Market from 2014 to 2021, statistical significance was found in the quality change effect of all four models. And there was no significant difference in explanatory power between the four models. Therefore, any of the four models should be introduced into the decision-making system for shipping time for apples.

• Journal of Korean Medicine for Obesity Research
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• v.23 no.2
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• pp.78-85
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• 2023

Objectives: Weight gain is one of the symptoms of hypothyroidism and it could deteriorate thyroid function. Our objectives are to evaluate weight changes and analyze adverse events in overweight and obese women with hypothyroidism who were prescribed Gamitaeeumjowee-tang. Methods: A retrospective chart review was conducted using medical records of patients with hypothyroidism, who had body mass indexes (BMI) above 23 and were prescribed Gamitaeeumjowee-tang for 12 weeks between August 2017 and November 2022. Reported adverse events (AEs) were assessed by severity, causality and system-organ classes. Results: Thirty patients were included (mean±standard deviation, age 46.10±9.94 years, weight 70.52±11.18 kg, BMI 28.30±3.80 kg/m²). The mean total weight loss of hypothyroidism patients was 5.45±2.77 kg, while the mean weight loss rate and mean BMI change were 7.66±3.41% and 2.18±1.07 kg/m², respectively. Among evaluated causality of adverse events, 'Unlikely' was predominant (80.8%) and severity assessment showed most of the symptoms were mild (91.7%). Conclusions: Gamitaeeumjowee-tang could be an option for hypothyroidism patients, who are overweight or obese, to lose weight and no serious adverse events occurred. Further well-designed clinical studies are recommended.

• Journal of Powder Materials
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• v.31 no.2
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• pp.152-162
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• 2024

The directed energy deposited (DED) alloys show higher hardness values than the welded alloys due to the finer microstructure following the high cooling rate. However, defects such as microcracks, pores, and the residual stress are remained within the DED alloy. These defects deteriorate the wear behavior so post-processing such as heat treatment and hot isostatic pressing (HIP) are applied to DED alloys to reduce the defects. HIP was chosen in this study because the high pressure and temperature uniformly reduced the defects. The HIP is processed at 1150℃ under 100 MPa for 4 hours. After HIP, microcracks are disappeared and porosity is reduced by 86.9%. Carbides are spherodized due to the interdiffusion of Cr and C between the dendrite and interdendrite region. After HIP, the nanohardness (GPa) of carbides increased from 11.1 to 12, and the Co matrix decreased from 8.8 to 7.9. Vickers hardness (HV) decreased by 18.9 % after HIP. The dislocation density (10^-2/m²) decreased from 7.34 to 0.34 and the residual stress (MPa) changed from tensile 79 to a compressive -246 by HIP. This study indicates that HIP is effective in reducing defects, and the HIP DED Stellite 6 exhibits a higher HV than welded Stellite 6.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.275-281
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• 1996

The objective of the study was to investigate the effects of water treatment sludge (WTS) on the growth of soybean and carrot, and uptake of some inorganic components in the plants. WTS was incorporated to field at the rates of 0, 1, 3, and 5 tons per 10a on the basis of dry weight. With the application of the sludge, OM and CEC in the soil increased slightly while the concentration of available phosphorous decreased. And heavy metals, including Pb, Cd, Cr, As and Hg, were not detected at the harvest stage in crops. With an increase in the application of the sludge, the concentration of phosphorous in the seed of soybean and the root of carrot tended to be decreased. There seems no correlation between rate of application of the sludge and uptake of Al in the plants. The yield of soybean was the highest when applied to one ton sludge and the yield on carrot increased with an increase in rate of applied sludge. Also, the concentration of carotene increased with an increased application of the sludge. But, application of WTS showed to deteriorate the visual quality with an irregularity of carrot's surface. This results indicate that application of WTS will be give a positive and negative effects on soil and crops.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1993.12a
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• pp.6-9
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• 1993

According to changes in population, economic conditions, life-stile and eating habits, the frui ts and vegetables market wi 11 be shi fted from processed (i. e. , canned) to fresh. Undressed fresh produce, consisting of washed, disinfected and peeled fruits and vegetables that either sliced or grated, are currently increased in demand by retail and institutional market which use them as salad components or in ready-to use foods, Main attributes of minimally processed fruits and vegetables are convenience and fresh-like quality. Minimally processed Products readily deteriorate in quality, especially color and texture, as a result of endogeneous enzyme enhanced respiration and microorganisms which lead to reduced shelf Iife. According to changes in population, economic conditions, life-stile and eating habits, the frui ts and vegetables market wi 11 be shi fted from processed (i. e. , canned) to fresh. Undressed fresh produce, consisting of washed, disinfected and peeled fruits and vegetables that either sliced or grated, are currently increased in demand by retail and institutional market which use them as salad components or in ready-to use foods, Main attributes of minimally processed fruits and vegetables are convenience and fresh-like quality. Minimally processed Products readily deteriorate in quality, especially color and texture, as a result of endogeneous enzyme enhanced respiration and microorganisms which lead to reduced shelf Iife. Thus. to prevent these undesirable changes , val'ious techniques such as controlled atmosphere (CA) storage, modified atmosphere OIA) storage, including vacuum packaging have been receiving considerable attention, Although milch research has been done to find optimal conditions for whole intact frui ts and vegetables, only limi ted information is avai lable on fresh cut. and other minimally processed products. 81 iced frui ts exhibi t increas~d ethylene production and respiration compal'ed to whole f, 'uits during distribution in response to tissue damage. As a result, accelerated senescence and enzymatic browning OCCUI', Recent l'esearch on minimally processed fl'uits and vegetables has mainly focused on methods to inhibit browning, due to ban on use of sulfur dioxide, In order to retard or prevent these physiological changes, val'ious al ternatives, reducing agents. acidulants, chelating agents and inol'ganic sal ts have been evaluated for use on fresh cut fl'ui ts. Al though some agents were effective replacement for sulfur dioxide. consum$\textregistered$I'S demandless use of chemical on such products. Shel~ life of minimally processed products has been extended by inhibition of metabolic reactions associated with loss of quality and by inhibition of aerobic spoilage caused by wide variety of microorganisms. Appl ication of ~I.-\ packaging, including vacuum packaging, retards the rate of respiration, prevents growth of aerobic spoilage organisms, inhibits oxidation and color deterioration. Tissue softening is another major problem in minimally processed products because enzymes re 1 a ted to ce 11 wa 11 degrada t i on are not inactivated. Various treatments have been investigated for retardation of the softening of sliced products. Some studies have concentrated on the application of an active packaging system with ~I, l. packaging and calcium infi 1 tration as possible measures to retain firmness of processed products. In my opinion, one important step for production of minimally processed frui ts wi th favorabl e color of cut surface and firm texture is the selection of better cultivar. As the view, changing tendency of fresh color by apple cultivars and relationship between the tendency and PPO activity will be discussed in the seminar. In addition to the topic, research result on quality enhancement of fresh apple slices by heat shock treatment will be introduced.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.6
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• pp.175-183
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• 2016

The government set up "national happiness, the hope of a new era of national vision under' job center of the creative economy" to achieve by national goals in the first and figure achieved through the establishment of new growth engines of the youth unemployment problem solve and national level there are a number of business start-up support. September 8, 2015 announced the Government's look at the '2016 Year of the budget, the government for new growth engines greatly promoted the venture entrepreneurship ecosystem revitalization and research and development (R & D) the business for enhanced performance in 2017. According to the direction of this study is to evaluate the current creative economy business incubator at the comparison whether the correct orientation mainly entrepreneurs, entrepreneurs preliminary recognition of student entrepreneurship ecosystem. Entrepreneurs 113 people in that way, 71 people pre-entrepreneurs, students 60, workers were founding agencies conducted an online survey of 47 people, 16 people Investors, 50 public and 11 additional persons including a total of 368 people. This study is in line with the orientation of these entrepreneurs to create economic status and recognition of the Republic of Korea entrepreneurship ecosystem, pre- entrepreneurs, students will examine the comparative analysis around. Analysis, social perception of entrepreneurship is somewhat higher than it was confirmed that the negative response of 32.2% to 36.3% of positive response. Social awareness of entrepreneurs showed a 2-fold higher response rate than the negative of response of 17.1% to 41.7% responding that positive recognition for the current start-up environment is bad, the response is good response to higher response rate than 23.5% to 41.1% It showed. The percentage of responses that better respect the entrepreneurship environment of the future Republic of Korea showed a higher response rate than the rate of 23% in response to deteriorate to 41.2%, with 52.9% awareness is the percentage that responded that the bad part about the ruthless Korea's entrepreneurship environment in China good part as response rate approximately three times greater than the 17.7% showed high response rates. Social awareness of entrepreneurs experience the presence of the founding start-up experience was confirmed that the more negative the number increases, the more the contrary the number of start-up experience increased awareness of the current and future environment of entrepreneurship was identified as a positive entrepreneurship environment. Also recognized was confirmed to change the parent of the more positive changes in the start-up of entrepreneurs doctor also positive about entrepreneurship, start-up entrepreneurs start with a doctor's motivation for founding non-economic reasons than for economic reasons has confirmed Higher. This study showed the overall level overview analysis of the status and recognition of the Republic of Korea entrepreneurship ecosystem. Future studies need to be a proposal for an existing previous studies for more precise direction to go forth to analyze the entrepreneurship ecosystem with a focus on problems and improvement of the Republic of Korea entrepreneurship ecosystem.

• Journal of dental hygiene science
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• v.2 no.2
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• pp.89-94
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• 2002

The present study attempts to find the ways to efficiently manage dental caries, one of the major causes of tooth loss, and to cope with oral diseases that deteriorate oral health. For this purpose, this study seeks to obtain fundamental data needed in planning the oral health projects. The study was conducted to the first-grade elementary school students in Hwa-Seong city, Gyeonggi-do, from April 1 - 30, 2002. The result was as follows: 1) Among a total of 2,710 subjects, 598 (274 boys and 324 girls) have more than 1 permanent tooth with a caries legion whether it was treated or not. 2) The number of permanent teeth examined is 6,029, in which girls' teeth are more (3,165) than boys' (2,864). 3) Out of a total of 6,029 teeth examined, 1,106 permanent teeth (508 boys' and 598 girls') have caries legions. 4) Out of 1,106 permanent teeth with caries legions, 170 (15.4%) were treated - 67 teeth for boys (13.2%) and 103 teeth for girls (17.2%). 5) 22.1% of the children have experienced dental caries in their permanent teeth. Among them, 20.1% are boys and 24.1% are girls. 6) The rate of the permanent teeth that once had, or now have caries legions are 21.2%, among which the rate for boy's teeth is 20.1% and that for girl's teeth is 22.1%. 7) The number of the permanent teeth that had caries legions is 0.5 for all the subjects. A boy has 0.4 and a girl has 0.5 teeth with caries legions regardless of whether it was treated or not. 8) The rate of the permanent teeth with caries legions is 86.7% for overall subjects - 88.3% for boys and 85.3% for girls. 9) The rate of treated permanent teeth is 13.3% for all the subjects - 11.7% for boys and 14.7% for girls. Based on the above result, the study draws a conclusion that in order to prevent dental caries in young students and to perform an early treatment for the dental caries that already occurred an oral health office should be installed at all the elementary schools so that elementary school students don't experience a loss of time and effort for learning and suffer nutritional imbalance or disorder. Besides, the oral health education concerning the importance of dental care should be conducted to the citizens, especially to the young people, in the community as an essential project of oral health centers in the community health offices, the public medical institutions.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.4
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• pp.639-648
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• 2013

Metabolic syndrome is the most important risk factors of cardiovascular diseases So, it is judged that Quality of life of persons with metabolic syndrome inevitably deteriorate. For the purpose, the study aims to analyse the number of risk factors, and the relationship between abnormality of each risk factor and Quality of life, targeting adult women aged more than 19. For this study, data from the National Health and Nutrition Behavior Survey in 2007 and 2008 were incorporated and 4,365 subjects were collected for the study. Version 17.0 SPSS was used for data analysis. Statistical significance was defined as p<0.05. As a result of the study, the prevalence rate of metabolic syndrome was 24.2%. According to the number of risk factors of metabolic syndrome the regression coefficient of Quality of life was -0.024 when the number of risk factor was one, -0.048 when there were two risk factors, -0.090 when there were three risk factors, -0.117 when there were four risk factors, and -0.168 when there were five risk factors. The regression coefficient(abnormal/normal)of risk factors of metabolic syndrome were as follows; Waist circumference -0.035, Blood pressure was -0.064, Fasting glucose was -0,026 and HDL cholesterol was -0.012. In conclusion, as it was discovered that risk factors of metabolic syndrome had significant relations with Quality of life, it is suggested that the relations between some significant variables and Quality of life should be actively considered so that adult women can perceive metabolic syndrome properly and endeavor to improve their Quality of life.

• Journal of KIISE
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• v.42 no.10
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• pp.1254-1267
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• 2015

Recently, excessive installations of APs have caused WLAN interference, and many techniques have been suggested to solve this problem. The AP aggregation technique serves to reduce active APs by moving station connections to a certain AP. Since this technique forcibly moves station connections, the transmission performance of some stations may deteriorate. The AP transmit power control technique may cause station disconnection or deterioration of transmission performance when power is reduced under a certain level. The combination of these two techniques can reduce interference through AP aggregation and narrow the range of interferences further through detailed power adjustment. However, simply combining these techniques may decrease the probability of power adjustment after aggregation and increase station disconnections upon power control. As a result, improvement in performance may be insignificant. Hence, this study suggests a scheme to combine the AP aggregation and the AP transmit power control techniques in OpenFlow-based WLAN to ameliorate the disadvantages of each technique and to reduce interferences efficiently by performing aggregation for the purpose of increasing the probability of adjusting transmission power. Simulations reveal that the average transmission delay of the suggested scheme is reduced by as much as 12.8% compared to the aggregation scheme and by as much as 18.1% compared to the power control scheme. The packet loss rate due to interference is reduced by as much as 24.9% compared to the aggregation scheme and by as much as 46.7% compared to the power control scheme. In addition, the aggregation scheme and the power control scheme decrease the throughput of several stations as a side effect, but our scheme increases the total data throughput without decreasing the throughput of each station.