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Freeze Risk Assessment for Three Major Peach Growing Areas under the Future Climate Projected by RCP8.5 Emission Scenario (신 기후변화시나리오 RCP 8.5에 근거한 복숭아 주산지 세 곳의 동해위험도 평가)

  • Kim, Soo-Ock;Kim, Dae-Jun;Kim, Jin-Hee;Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.14 no.3
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    • pp.124-131
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    • 2012
  • This study was carried out to evaluate a possible change in freeze risk for 'Changhowon Hwangdo' peach buds in three major peach growing areas under the future climate projected by RCP8.5 emission scenario. Mean values of the monthly temperature data for the present decade (2000s) and the future decades (2020s, 2050s, 2080s) were extracted for farm lands in Icheon, Chungju, and Yeongcheon-Gyeongsan region at 1km resolution and 30 sets of daily temperature data were generated randomly by a stochastic process for each decade. The daily data were used to calculate a thermal time-based dormancy depth index which is closely related to the cold tolerance of peach buds. Combined with daily minimum temperature, dormancy depth can be used to estimate the potential risk of freezing damage on peach buds. When the freeze risk was calculated daily for the winter period (from 1 November to 15 March) in the present decade, Icheon and Chungju regions had high values across the whole period, but Yeongcheon-Gyeongsan regions had low values from mid-December to the end of January. In the future decades, the frequency of freezing damage would be reduced in all 3 regions and the reduction rate could be as high as 75 to 90% by 2080's. However, the severe class risk (over 80% damage) will not disappear in the future and most occurrences will be limited to December to early January according to the calculation. This phenomenon might be explained by shortened cold hardiness period caused by winter warming as well as sudden cold waves resulting from the higher inter-annual climate variability projected by the RCP8.5 scenario.

The Generation of Westerly Waves by Sobaek Mountains (소백산맥에 의한 서풍 파동 발생)

  • Kim, Jin wook;Youn, Daeok
    • Journal of the Korean earth science society
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    • v.38 no.1
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    • pp.24-34
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    • 2017
  • The westerly waves generation is described in the advanced earth science textbook used at high school as follows: as westerly wind approaches and blows over large mountains, the air flow shows wave motions in downwind side, which can be explained by the conservation of potential vorticity. However, there has been no case study showing the phenomena of the mesoscale westerly waves with observational data in the area of small mountains in Korea. And thus the wind speed and time persistency of westerly winds along with the width and length of mountains have never been studied to explain the generation of the westerly waves. As a first step, we assured the westerly waves generated in the downwind side of Sobaek mountains based on surface station wind data nearby. Furthermore, the critical or minimum wind velocity of the westerly wind over Sobaek mountains to generate the downwind wave were derived and calcuated tobe about $0.6m\;s^{-1}$ for Sobaek mountains, which means that the westerly waves could be generated in most cases of westerly blowing over the mountains. Using surface station data and 4-dimensional assimilation data of RDAPS (Regional Data Assimilation and Prediction System) provided by Korea Meteorological Agency, we also analyzed cases of westerly waves occurrence and life cycle in the downwind side of Sobaek mountains for a year of 2014. The westerly waves occurred in meso-${\beta}$ or -${\gamma}$ scales. The westerly waves generated by the mountains disappeared gradually with wind speed decreasing. The occurrence frequency of the vorticity with meso-${\beta}$ scale got to be higher when the stronger westerly wind blew. When we extended the spatial range of the analysis, phenomena of westerly waves were also observed in the downwind side of Yensan mountains in Northeastern China. Our current work will be a study material to help students understand the atmospheric phenomena perturbed by mountains.

A study on the factors associated with treatment compliance in adolescent orthodontic patients (청소년기 교정환자의 치료 협조도와 연관된 요소에 관한 연구)

  • Kim, Jin-Ee;Cha, Bong-Kuen;Lee, Nam-Ki
    • The korean journal of orthodontics
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    • v.34 no.2 s.103
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    • pp.177-188
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    • 2004
  • This study is aimed at providing the variables associated with adolescent compliance In orthodontic treatment, and identifies the salient predictors of cooperative behaviors over the course of treatment. Orthodontic attitude scale, orthodontic locus of control scale and demographics data were obtained for 60 adolescent orthodontic patients who had been in treatment a minimum of 10 months. This data was then analyzed in relation to their sex, school age and treatment compliance. The following results were obtained. 1. The scoring of external-powerful others-parents, subscale of the Orthodontic Locus of Control scale, found a statistically significant difference between sex differences (p<0.05). The score of boys was higher than that of girls. 2. The external-powerful others-parents score from the Orthodontic Locus of Control scale showed a significantly positive correlation (p<0.05) with the level of compliance. 3. The salient factors associated with compliance were the adolescent patients' own cognition and decisions. 4. There was a statistically significant correlation between the length of treatment and patient compliance (p<0.05). Thus, there was a substantial decrease in the cooperation of orthodontic patients over time. 5. Other independent variables including age, sex, family environment, religion, academic standing, parents' occupation and education, and brushing frequency were investigated and did not yield any significant relationships. Patient compliance is a critical factor in the efficacy of orthodontic treatment. Individuals vary greatly in their perceptions and attitudes of orthodontic treatment, sociodemographic environments and personality characteristics. In assessing the level of compliance attainable by each individual patient it is advisable To pay sufficient attention not only to the technical matters but also to the psychologic aspects of the treatment progress.

Quality Characteristics of Rough Rice during Low Temperature Drying (저온건조 중 벼의 품질 특성)

  • Kim, Hoon;Han, Jae-Woong
    • Food Science and Preservation
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    • v.16 no.5
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    • pp.650-655
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    • 2009
  • This study was conducted to measure the quality characteristics of rough rice during low temperature drying by using an experimental dryer and heat pump with a capacity of 150kg at four temperature levels of 20, 30, 40, and $50^{\circ}C$. The quality and proper drying temperature of rough rice was investigated by measuring variations in moisture content, crack rates, germination rates and cooked rice. Temperatures over $40^{\circ}C$ is considered a high-temperature area, and below $40^{\circ}C$ is considered a low-temperature area. The drying rates were 0.3, 0.6, 0.9, and 1.3%/hr, and the crack ratios were 0, 1.6, 6.8, and 24.2% at the drying temperatures of 20, 30, 40, and $50^{\circ}C$, respectively, which showed that the higher the drying temperature was, the higher the drying rate and crack rate was. Therefore, 20 and $30^{\circ}C$ were found to be appropriate drying temperatures for avoiding crack formation, and $50^{\circ}C$ was inappropriate. At $40^{\circ}C$, the operation methods needed to be modified to limit cracking, such as increasing the tempering time. Also, as the drying temperature increased, the germination rate decreased. Germination rates at 20 and $30^{\circ}C$ were suitable for using the rough rice as a seed, and those at 40 and $50^{\circ}C$ were over 80%, which is the minimum allowable percentage. In the sensory evaluation of cooked rice, the quality of appearance, taste, and texture varied as a function of drying temperature. When considering these factors, the cooked rice that was dried at 20 and $30^{\circ}C$ was better than the cooked rice dried at high-temperature. Consequently, in view of drying temperature and rates, the best conditions for drying rough rice were below $30^{\circ}C$ and below 0.6%/hr.

Effect of Sugars on the Bacterial Spoilage of Ground Meat (당류(糖類)의 첨가(添加)가 육(肉)의 세균성(細菌性) 부패(腐敗)에 미치는 영향(影響))

  • Kim, Oun-Hyun;Kim, Chang-Han
    • Korean Journal of Food Science and Technology
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    • v.11 no.4
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    • pp.217-223
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    • 1979
  • The present study was to investigate the effect of sugars on the psychrophillic spoilage in ground meat. The obtained results were summarized as follows: 1. The minimum pH values for the ground beef containing 2, 5 and 10 % glucose were 5.25, 5.15 and 4.5, respectively. For the ground pork, the respective values were 5.1, 4.45 and 4.1. 2. Total aerobes, coliform, lactic acid bacteria and lactobacillus counts per gram for the control and 2% glucose-contained ground beef after 9 days for storage at $5^{\circ}C$ were $8.3{\times}10^9vs\;6.0{\times}10^7,\;3.5{\times}10^5vs\;2.4{\times}10^3,\;5.8{\times}10^7vs\;4.7{\times}10^6$ and $3.6{\times}10^5vs\;4.2{\times}10^6$ respectively. For the ground pork, the respective values were $1.2{\times}10^{10}vs\;7.8{\times}10^8,\;3.4{\times}10^5vs\;3.1{\times}10^4,\;5.5{\times}10^7vs\;4.5{\times}10^6$ and $3.3{\times}10^5vs\;3.7{\times}10^5$. The glucose-added ground meat showed higher counts than those of the controls only in the case of lactobacillus without any apparent adverse effects. 3. The length of storage time until the depletion of added glucose was 12, 16 and 28 days for the 2, 5 and 10 % glucose contained ground beef and 9, 16 and 30 days for the ground pork, respectively. pH did not start to increase until the added glucose was depleted completely. 4. The addition of glucose extended significantly the average shelf-life of ground beef at refrigeration condition $(5^{\circ}C)$. The extended shelf-life over the control was 7, 9 and 12days for the 2, 5 and 10 % glucose contained ground beef and 8, 10 and 12 days for the respective ground porks. 5. Although the addition of disaccharides (maltose, lactose, saccharose) lowered the pH of ground meat, the extension of shelf-life as seen in glucose treatment was not affected. In fact, the higher the concentration of added disaccharides was, the greater the degree of putrefaction occurred.

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Spring Phonology of a Grapevine Cultivar under the Changing Climate in Korea during 1921-2000 (겨울기온 상승에 따른 낙엽과수의 휴면생태 변화)

  • Jung Jea-Eun;Seo Hee-Cheol;Chung U-Ran;Yun Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.8 no.2
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    • pp.116-124
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    • 2006
  • Remarkable winter season warming has been observed in East Asian countries during the last century. Accordingly, significant effects on dormancy and the resulting budburst of deciduous trees are expected. However phenological observations are rare and insufficient compared with the long-time climate records in the same region. A chill-day accumulation, which can be estimated from daily maximum and minimum temperature, is expected to make a reasonable proxy for dormancy depth of temperate zone fruit trees. To simulate dormancy depth during 1921-2004, a chill-day model parameterized for 'Campbell Early' grapevine, which is the major cultivar grown virtually anywhere in South Korea, was applied to daily temperature data at 8 locations in South Korea. The calculations showed that the chilling requirement for breaking endo-dormancy of this grapevine cultivar can be satisfied by mid-January to late February in South Korea, and the date was delayed going either northward or southward from the 'Daegu-Jeonju' line crossing the middle of South Korea in the east-west direction. Maximum length of the cold tolerant period (the number of days between endo-dormancy release and forced dormancy release) showed the same spatial pattern. When we divide the 83 years into 3 periods (I: 1921-1950, II: 1951-1980, and III: 1981-2004) and get the average of each period, dormancy release date of period III was accelerated by as much as 15 days compared with that of period I at all locations except Jeju (located in the southernmost island with subtropical climate) where an average15-day delay was predicted. The cold- tolerant period was also shortened at 6 out of 8 locations. As a result, budburst of 'Campbell Early' in spring was accelerated by 6 to 10 days at most locations, while inter-annual variation in budburst dates was increased at all locations. The earlier budburst after the 1970s was due to (1) warming in winter resulting in earlier dormancy release (Incheon, Mokpo, Gangneung, and Jeonju), (2) warming in early spring accelerating regrowth after breaking dormancy (Busan and Jeju), and (3) both of them (Seoul and Daegu).

Object Tracking Based on Exactly Reweighted Online Total-Error-Rate Minimization (정확히 재가중되는 온라인 전체 에러율 최소화 기반의 객체 추적)

  • JANG, Se-In;PARK, Choong-Shik
    • Journal of Intelligence and Information Systems
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    • v.25 no.4
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    • pp.53-65
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    • 2019
  • Object tracking is one of important steps to achieve video-based surveillance systems. Object tracking is considered as an essential task similar to object detection and recognition. In order to perform object tracking, various machine learning methods (e.g., least-squares, perceptron and support vector machine) can be applied for different designs of tracking systems. In general, generative methods (e.g., principal component analysis) were utilized due to its simplicity and effectiveness. However, the generative methods were only focused on modeling the target object. Due to this limitation, discriminative methods (e.g., binary classification) were adopted to distinguish the target object and the background. Among the machine learning methods for binary classification, total error rate minimization can be used as one of successful machine learning methods for binary classification. The total error rate minimization can achieve a global minimum due to a quadratic approximation to a step function while other methods (e.g., support vector machine) seek local minima using nonlinear functions (e.g., hinge loss function). Due to this quadratic approximation, the total error rate minimization could obtain appropriate properties in solving optimization problems for binary classification. However, this total error rate minimization was based on a batch mode setting. The batch mode setting can be limited to several applications under offline learning. Due to limited computing resources, offline learning could not handle large scale data sets. Compared to offline learning, online learning can update its solution without storing all training samples in learning process. Due to increment of large scale data sets, online learning becomes one of essential properties for various applications. Since object tracking needs to handle data samples in real time, online learning based total error rate minimization methods are necessary to efficiently address object tracking problems. Due to the need of the online learning, an online learning based total error rate minimization method was developed. However, an approximately reweighted technique was developed. Although the approximation technique is utilized, this online version of the total error rate minimization could achieve good performances in biometric applications. However, this method is assumed that the total error rate minimization can be asymptotically achieved when only the number of training samples is infinite. Although there is the assumption to achieve the total error rate minimization, the approximation issue can continuously accumulate learning errors according to increment of training samples. Due to this reason, the approximated online learning solution can then lead a wrong solution. The wrong solution can make significant errors when it is applied to surveillance systems. In this paper, we propose an exactly reweighted technique to recursively update the solution of the total error rate minimization in online learning manner. Compared to the approximately reweighted online total error rate minimization, an exactly reweighted online total error rate minimization is achieved. The proposed exact online learning method based on the total error rate minimization is then applied to object tracking problems. In our object tracking system, particle filtering is adopted. In particle filtering, our observation model is consisted of both generative and discriminative methods to leverage the advantages between generative and discriminative properties. In our experiments, our proposed object tracking system achieves promising performances on 8 public video sequences over competing object tracking systems. The paired t-test is also reported to evaluate its quality of the results. Our proposed online learning method can be extended under the deep learning architecture which can cover the shallow and deep networks. Moreover, online learning methods, that need the exact reweighting process, can use our proposed reweighting technique. In addition to object tracking, the proposed online learning method can be easily applied to object detection and recognition. Therefore, our proposed methods can contribute to online learning community and object tracking, detection and recognition communities.

Antibiotics Susceptability of Streptococcus pneumoniae Isolated from Pharynx in Healthy Korean Children and Choice of Proper Empirical Oral Antibiotics Using Pharmacokinetics/Pharmacodynamics Model (국내의 소아에서 분리된 폐구균의 항생제 감수성 양상 및 약력동학 모델을 이용한 적절한 항생제의 선택)

  • Paik, Ji Yeun;Choi, Jae Hong;Cho, Eun Young;Oh, Chi Eun;Lee, Jina;Choi, Eun Hwa;Lee, Hoan Jong
    • Pediatric Infection and Vaccine
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    • v.18 no.2
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    • pp.109-116
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    • 2011
  • Purpose : Pneumococcus is one of the most important causes of invasive infection through the childhood period. In January 2008, the Clinical and Laboratory Standards Institute (CLSI) published revised penicillin breakpoints for Streptococcus pneumoniae and penicillin susceptibility rates of S. pneumoniae increased in Korea. This study was performed to determine the probability of oral amoxicillin for the empirical treatment achieving bactericidal exposure against pneumococcus using pharmacodynamics model. Methods : Twenty-three isolates of pneumococci were subjected to determine minimum inhibitory concentration (MIC) for ${\beta}$-lactams and macrolide. For the ${\beta}$-lactams, exposure of fT >MIC (time that free drug concentrations remain above the MIC) for 50% of the administration interval have determined the probability of target attainment (PTA), and regimens that had a PTA >90% were considered optimal. An analysis was performed by applying MIC of 23 isolates to a 5000-patient Monte Carlo simulation model. Results : Among 23 isolates from healthy children, 7 (30.4%) isolates were MIC ${\leq}$1.0 ${\mu}g$/mL and 19 (82.6%) were MIC ${\leq}$2 ${\mu}g$/mL for amoxicillin. Amoxicillin 40 mg/kg/day achieved PTA >90% at MIC ${\leq}$1.0 ${\mu}g$/mL but PTA decreased to 52% at MIC 2 ${\mu}g$/mL, whereas amoxicillin 90 mg/kg/day can predict 97% of PTA at MIC 2 ${\mu}g$/mL. Overall, oral amoxicillin 90 mg/ kg/day for the empirical treatment against pneumococcus can expect more successful response in Korean children. Conclusion : Considering the resistantce pattern of pneumococci in Korean children, we estimate that oral amoxicillin 90 mg/kg/day will provide a pharmacodynamic advantage for the empirical treatment against pneumococcus. And low dose amoxicillin or macrolide are expected to have higher chance of treatment failure than high dose oral amoxicillin.

Performance Analysis of Photovoltaic System for Greenhouse (태양광 발전시스템의 발전 성능 분석)

  • Kwon, Sun-Ju;Min, Young-Bong;Choi, Jin-Sik;Yoon, Yong-Cheol
    • Journal of agriculture & life science
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    • v.46 no.5
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    • pp.143-152
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    • 2012
  • This study was performed to reduce the operating cost of a greenhouse by securing electric energy required for greenhouse operation. Therefore, it experimentally reviewed the performance analysis of photovoltaic system in terms of maximum amount of generated electric power based on the amount of horizontal solar radiation during daytime. That is to say, the maximum solar radiation at 300, 400, 500, 600, 700, 800 and 900 W. $m^{-2}$, respectively. The amount of momentary electric power of the photovoltaic system at any was about 970 W and we found that the momentary efficiency of the photovoltaic system that was used for this experiment was 97%. In the case of this system, we found that electric power will be generated when amount of horizontal solar radiation is more than 200 W. $m^{-2}$, at minimum. If the amount of horizontal solar radiation is increased, the maximum power generation is also increased. At that time, the maximum efficiencies were 30, 78, 86 and 90%, respectively. However, when the amount of insolation was about 800 W. $m^{-2}$, the maximum power generation tended to be lower than 700 W. $m^{-2}$. The efficiency which caused the maximum electric power was decreased to less than 97% of the momentary generated electric power. When the total amounts of horizontal solar radiation per day were 3.24, 8.10, 10, 90, 12.70, 14.33, 19.53 and $21.48MJ{\cdot}m^{-2}$ respectively, the total amounts of power energy were 0.03, 0.40, 3.60, 4.37, 4.71, 4.70 and 4.91 kWh. And it represented that the total amounts of power energy were either decreased or increased a bit on the border between some solar radiations. The temperature at the back of the array tended to be higher than the temperature at the front but it demonstrated an increased when the amount of solar radiation increased. In the case of this system, the performance of the module in terms of degradation has not been shown yet.

A New White Wheat Variety, "Jeokjoong" with High Yield, Good Noodle Quality and Moderate to Scab (백립계 다수성 붉은곰팡이병 중도저항성 제면용 밀 신품종 "적중밀")

  • Park, Chlul Soo;Heo, Hwa-Young;Kang, Moon-Suk;Lee, Chun-Kee;Park, Kwang-Geun;Park, Jong-Chul;Kim, Hong-Sik;Kim, Hag-Sin;Hwang, Jong-Jin;Cheong, Young-Keun;Kim, Jung-Gon
    • Korean Journal of Breeding Science
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    • v.40 no.3
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    • pp.308-313
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    • 2008
  • "Jeokjoong", a white winter wheat (Triticum aestivum L.) variety was developed from the cross "Keumkang"/"Tapdong". "Jeokjoong" is an awned, semi-dwarf and soft white winter wheat, similar to "Keumkang" (check variety). The heading and maturing date of "Jeokjoong" were similar to "Keumkang". Culm and spike length of "Jeokjoong" were 78 cm and 7.5 cm, similar to "Keumkang". "Jeokjoong" had lower test weight (800 g) and lower 1,000-grain weight (40.1 g) than "Keumkang" (811 g and 44.0 g, respectively). It had resistance to winter hardiness, wet-soil tolerance and lodging tolerance. "Jeokjoong" showed moderate to scab in test of specific character although "Keumkang" is susceptible to scab. "Jeokjoong" had lower flour yield (69.2%) and ash content (0.36%) than "Keumkang" (72.0% and 0.41%, respectively) and similar flour color to "Keumkang". It showed lower protein content (8.9%) and SDS-sedimentation volume (36.8 ml) and shorter mixograph mixing time (3.5 min) than "Keumkang" (11.0%, 59.7 ml and 4.5 min, respectively). Amylose content and pasting properties of "Jeokjoong" were similar to "Keumkang". "Jeokjoong" had softer and more elastic texture of cooked noodles than "Keumkang". Average yield of "Jeokjoong" in the regional adaptation yield trial was 6.19 MT ha-1 in upland and 5.33 MT/ha in paddy field, which was 19% and 16% higher than those of "Keumkang" (5.21 MT/ha and 4.58 MT/ha, respectively). "Jeokjoong" would be suitable for the area above the daily minimum temperature of $-10^{\circ}C$ in January in Korean peninsula.