• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.55-64
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• 2019

The flowering seasons can be advanced due to climate change that would cause an abnormally warm winter. Such warm winter would increase the frequency of crop damages resulted from sudden occurrences of low temperature before and after the vegetative growth stages, e.g., the period from germination to flowering. The degree and pattern of freezing damage would differ by the development stage of each individual fruit tree even in an orchard. A critical temperature, e.g., killing temperature, has been used to predict freeze damage by low-temperature conditions under the assumption that such damage would be associated with the development stage of a fruit flower bud. However, it would be challenging to apply the critical temperature to a region where spatial variation in temperature would be considerably high. In the present study, a phenological model was used to estimate major bud development stages, which would be useful for prediction of regional risks for the freeze damages. We also derived a linear function to calculate a probabilistic freeze risk in spring, which can quantitatively evaluate the risk level based solely on forecasted weather data. We calculated the dates of freeze damage occurrences and spatial risk distribution according to main production areas by applying the spring freeze risk function to apple, peach, and pear crops in 2018. It was predicted that the most extensive low-temperature associated freeze damage could have occurred on April 8. It was also found that the risk function was useful to identify the main production areas where the greatest damage to a given crop could occur. These results suggest that the freezing damage associated with the occurrence of low-temperature events could decrease providing early warning for growers to respond abnormal weather conditions for their farm.

• Journal of the Korean earth science society
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• v.43 no.5
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• pp.591-603
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• 2022

The color and optical properties of seawater are determined by the interaction between dissolved organic and inorganic substances and plankton contained in it. The Ieodo - Ocean Research Institute (I-ORS), located in the East China Sea, is affected by the low salinity of the Yangtze River in the west and the Tsushima Warm Current in the south. Thus, it is a suitable site for analyzing the fluctuations in circulation and optical properties around the Korean Peninsula. In this study, seawater surrounding the I-ORS was classified according to its optical characteristics using the satellite remote reflectance observed with Moderate Resolution Imaging Spectroradiometer (MODIS)/Aqua and National Aeronautics and Space Administration (NASA) bio-Optical Marine Algorithm Dataset (NOMAD) from January 2016 to December 2020. Additionally, the variation characteristics of optical water types (OWTs) from different seasons were presented. A total of 59,532 satellite match-up data (d ≤ 10 km) collected from seawater surrounding the I-ORS were classified into 23 types using the spectral angle mapper. The OWTs appearing in relatively clear waters surrounding the I-ORS were observed to be greater than 50% of the total. The maximum OWTs frequency in summer and winter was opposite according to season. In particular, the OWTs corresponding to optically clear seawater were primarily present in the summer. However, the same OWTs were lower than overall 1% rate in winter. Considering the OWTs fluctuations in the East China Sea, the I-ORS is inferred to be located in the transition zone of seawater. This study contributes in understanding the optical characteristics of seawater and improving the accuracy of satellite ocean color variables.

• The Journal of Korean Academy of Prosthodontics
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• v.40 no.1
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• pp.1-17
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• 2002

The purpose of this study is to examine the possibility of thermal injury to bone tissues during an implant site preparation under the same condition as a typical clinical practice of $Br{\aa}nemark$ implant system. All the burs for $Br{\aa}nemark$ implant system were studied except the round bur The experiments involved 880 drilling cases : 50 cases for each of the 5 steps of NP, 5 steps of RP, and 7 steps of WP, all including srew tap, and 30 cases of 2mm twist drill. For precision drilling, a precision handpiece restraining system was developed (Eungyong Machinery Co., Korea). The system kept the drill parallel to the drilling path and allowed horizontal adjustment of the drill with as little as $1{\mu}m$ increment. The thermocouple insertion hole. that is 0.9mm in diameter and 8mm in depth, was prepared 0.2mm away from the tapping bur the last drilling step. The temperatures due to countersink, pilot drill, and other drills were measured at the surface of the bone, at the depths of 4mm and 8mm respectively. Countersink drilling temperature was measured by attaching the tip of a thermocouple at the rim of the countersink. To assure temperature measurement at the desired depths, 'bent-thermocouples' with their tips of 4 and 8mm bent at $120^{\circ}$ were used. The profiles of temperature variation were recorded continuously at one second interval using a thermometer with memory function (Fluke Co. U.S.A.) and 0.7mm thermocouples (Omega Co., U.S.A.). To simulate typical clinical conditions, 35mm square samples of bovine scapular bone were utilized. The samples were approximately 20mm thick with the cortical thickness on the drilling side ranging from 1 to 2mm. A sample was placed in a container of saline solution so that its lower half is submerged into the solution and the upper half exposed to the room air, which averaged $24.9^{\circ}C$. The temperature of the saline solution was maintained at $36.5^{\circ}C$ using an electric heater (J. O Tech Co., Korea). This experimental condition was similar to that of a patient s opened mouth. The study revealed that a 2mm twist drill required greatest attention. As a guide drill, a twist drill is required to bore through a 'virgin bone,' rather than merely enlarging an already drilled hole as is the case with other drills. This typically generates greater amount of heat. Furthermore, one tends to apply a greater pressure to overcome drilling difficulty, thus producing even greater amount heat. 150 experiments were conducted for 2mm twist drill. For 140 cases, drill pressure of 750g was sufficient, and 10 cases required additional 500 or 100g of drilling pressure. In case of the former. 3 of the 140 cases produced the temperature greater than $47^{\circ}C$, the threshold temperature of degeneration of bone tissue (1983. Eriksson et al.) which is also the reference temperature in this study. In each of the 10 cases requiring extra pressure, the temperature exceeded the reference temperature. More significantly, a surge of heat was observed in each of these cases This observations led to addtional 20 drilling experiments on dense bones. For 10 of these cases, the pressure of 1,250g was applied. For the other 10, 1.750g were applied. In each of these cases, it was also observed that the temperature rose abruptly far above the thresh old temperature of $47^{\circ}C$, sometimes even to 70 or $80^{\circ}C$. It was also observed that the increased drilling pressure influenced the shortening of drilling time more than the rise of drilling temperature. This suggests the desirability of clinically reconsidering application of extra pressures to prevent possible injury to bone tissues. An analysis of these two extra pressure groups of 1,250g and 1,750g revealed that the t-statistics for reduced amount of drilling time due to extra pressure and increased peak temperature due to the same were 10.80 and 2.08 respectively suggesting that drilling time was more influenced than temperature. All the subsequent drillings after the drilling with a 2mm twist drill did not produce excessive heat, i.e. the heat generation is at the same or below the body temperature level. Some of screw tap, pilot, and countersink showed negative correlation coefficients between the generated heat and the drilling time. indicating the more the drilling time, the lower the temperature. The study also revealed that the drilling time was increased as a function of frequency of the use of the drill. Under the drilling pressure of 750g, it was revealed that the drilling time for an old twist drill that has already drilled 40 times was 4.5 times longer than a new drill The measurement was taken for the first 10 drillings of a new drill and 10 drillings of an old drill that has already been used for 40 drillings. 'Test Statistics' of small samples t-test was 3.49, confirming that the used twist drills require longer drilling time than new ones. On the other hand, it was revealed that there was no significant difference in drilling temperature between the new drill and the old twist drill. Finally, the following conclusions were reached from this study : 1 Used drilling bur causes almost no change in drilling temperature but increase in drilling time through 50 drillings under the manufacturer-recommended cooling conditions and the drilling pressure of 750g. 2. The heat that is generated through drilling mattered only in the case of 2mm twist drills, the first drill to be used in bone drilling process for all the other drills there is no significant problem. 3. If the drilling pressure is increased when a 2mm twist drill reaches a dense bone, the temperature rises abruptly even under the manufacturer-recommended cooling conditions. 4. Drilling heat was the highest at the final moment of the drilling process.

• (The) Research of the performance art and culture
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• no.34
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• pp.277-313
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• 2017

This study is to find out the correlation with buddhist music after analyzing the rhythm of six pieces of PanYeombul sung by Kim Janggil out of Ogu exorcism of East coast the findings summarized are as follows. First, PanYeombul by Kim Janggil, performed on Oct, 16, 2016, was composed of , , , , , , , , , , and . Still, even if PanYeombul is performed by the same male shaman, the composition can be added or left out depending on some circumstances, which means the procedures are flexible. Seeing that there is common component of in additoin to compared with Kimyongtaek, it can be said that the component of is an important part in PanYeombul of Ogu exorcism of East coast Second, is usually referred to 'SinmyojangguDaedalani' in buddhist ritual, While Kim yongtaek accepts this practice in title, Kim Janggil uses 'YeomhwajangguDaedalani' as the title which makes his song different from others. Yeomhwa means "picking up flowers with fingers" which has been used in buddhism, not in common Considering this fact, the conclusion can be reached that by using the term 'Daedalani' from a buddhist chant, but making differentiation from buddhism, Kim Janggil is making the effort to be different from buddhist rituals. give some unique meaning to shaman rituals. Third, PanYeombul of Ogu exorcism of East coast may be divided into two main parts - the former part is PanYeombul and the latter part is Jiokga. In performing PanYeombul, male shaman sits singing alone and playing Jing himself, on the other hand, in case of Jiokga, he stands singing a solo with gwaeggwari in his hand accompanied by other musicians with the rhythm of Samgongjaebi. As the song and the accompaniment are in the form of giving and taking like duet. it is in peak in terms of music. Accordingly, PanYeombul can be divided into PanYeombul and Jiokga, But since it is performed by one male shaman and sung a solo, it is usually seen as one procedure. Jing, which is a kind of accompaniment in PanYeombul by Kim Janggil, has the role to distinguish a phrase and settle the musical paragraph. When the buddhist chant with one word-one note is performed. it requires the performer to catch his or her breath or clear throat. Just then, Jing comes out for filling out the intervals. Also, its role to distinguish a phrase and settle the musical paragraph helps make it clear to deliver words. The rhythm of Jing is mostly made up of small triple time except equal small binary time, comes out with overwhelmingly more frequency of Sutsoe(♪♩) than Amsoe(♩♪), and often shows syncopation. By often using Off Beat or short-long rhythm even in accompaniment of equal small binary time, he tris to give some variation to monotonous and equal rhythm for the musical vitality. These are similar to Sutsoe rhythm which can evoke tension and Kim Janggil makes these things his characierisiic of rhythm. Fifth, all the pieces consist of mi, sol, la, do, re and the descending melody like do'${\searrow}$la${\searrow}$sol${\searrow}$mi appears most frequently. The descending melody usually arouses the feeling of sorrow, so the sadness for the deceased is presented properly, which suggests his musical talent. Generally, pieces take on Menari-tori as a whole where the length of sol appears for a short time in descending la${\searrow}$sol${\searrow}$mi of perfect four degrees. Sixth, Even he accepts the lines of buddhist chant, he changes them in some degree. For example, he inserted some words between lines like 'Wonwangsaeng' and 'NamuAmitabul' and added Korean words like hapsosa to the lines of buddhist service written in Chinese character. Also, he inserted some words like 'iiiiiii~' to express the feeling of sadness. These are to maximize the desire of the deceased to go to the heaven and at the same time to diminish the sign of buddhism and strengthen the features of shamanism. Seventh, the effort to decrease the sign of buddhism is made in pasting lines of two songs. For example, Between the last words 'Wonsuaenapsu of Dage and the first words 'Jisimgwimyeongrye' of Chiljeongrye, there is usually a short pause to distinguish paragraphs, But he continues two songs without any pause to get rid of the feelings of buddhist chant. In terms of melody, he makes a distance from buddhist chant in an effort that he gives some traits to shaman rituals which are different from buddhist even if he uses the lines of buddhist rituals. Eighth, the analyzed pieces can be in four categories - no regular melody , , equal small binary time , eotmori melody of ten eighth time with 3+2+3+2 mixed small time . and Samgongjaebi melody 3+2+3 mixed small time . Each piece has its unique melody. Although of buddhist ritual is often performed, by using eotmori melody, he evokes the feeling of shaman and is another example of giving unique characteristic to the shaman of East coast by using Samgongjaebi melody.