• Journal of Environmental Science International
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• v.25 no.3
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• pp.345-359
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• 2016

This study analyze the synoptic meteorological cause of rainfall, rainfall intensity, drop size distribution(DSD), fall velocity and oblateness measured by the 2D-Video distrometer(2DVD) by comparing two cases which are heavy rainfall event case and a case that is not classified as heavy rainfall but having more than $30mm\;h^{-1}$ rainrate in July, 2014 at Gimhae region. As a results; Over the high pressure edge area where strong upward motion exists, the convective rain type occurred and near the changma front, convective and frontal rainfall combined rain type occurred. Therefore, rainrate varies based on the synoptic meteorological condition. The most rain drop distribution appeared in the raindrops with diameters between 0.4 mm and 0.6 mm and large particles appeared for the convective rain type since strong upward motion provide favorable conditions for the drops to grow by colliding and merging so the drop size distribution varies based on the location or rainfall types. The rainfall phases is mainly rain and as the diameter of the raindrop increase the fall velocity increase and oblateness decrease. The equation proposed based on the 2DVD tends to underestimated both fall velocity and oblateness compared with observation. Since these varies based on the rainfall characteristics of the observation location, standard equation for fall velocity and oblateness fit for Gimhae area can be developed by continuous observation and data collection hereafter.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.E3
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• pp.87-94
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• 2005

Wet scavenging by rain drops is a most important removal process of air pollutants. In order to study the scavenging mechanisms of aerosol particles, the characteristics of chemical components in the rain water were examined as a function of the amount of rainfall. Rain water were collected continuously and separated into the soluble and insoluble components. The elemental concentrations in both components were determined by a PIXE analysis. The physical and chemical characteristics of atmospheric aerosols during the rainfall events were measured simultaneously. The elemental concentrations in rain water decreased substantially just after rain started and then gradually declined in subsequential rain fall exceeding 1.0 mm. The large particles were scavenged more easily than the fine particles. Fe, Ti and Si in rain water were in high insoluble state. Contrarily, almost whole of S was dissolved in rain water.

• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.389-394
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• 2014

This study was conducted to find out the soil $CO_2$ emission characteristic due to rain fall pattern and intensity changes. Using Automatic Opening and Closing Chambers (AOCCs), we have measured annual soil respiration changes in Pinus koraiensis plantation at Seoul National University experimental forest in Mt. Taehwa. In addition, we have monitored heterotrophic respiration at trenching sites ($4{\times}6m$). Based on the one year data of soil respiration and heterotrophic respiration, we observed that 24% of soil respiration was derived from root respiration. During the rainy season (end of July to September), soil respiration at trenching site and trenching with rainfall interception site were measure during portable soil respiration analyzer (GMP343, Vaisala, Helsinki, Finland). Surprisingly, even after days of continuous heavy rain, soil water content did not exceed 20%. Based on this observation, we suggest that the maximum water holding capacity is about 20%, and relatively lower soil water contents during the dry season affect the vital degree of trees and soil microbe. As for soil respiration under different rain intensity, it was increased about 14.4% under 10 mm precipitation. But the high-intensity rain condition, such as more than 10 mm precipitation, caused the decrease of soil respiration up to 25.5%. Taken together, this study suggests that the pattern of soil respiration can be regulated by not only soil temperature but also due to the rain fall intensity.

• Journal of Industrial Technology
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• v.27 no.B
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• pp.221-227
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• 2007

This research investigates the turbidity and flow of river for an year, 2005, in order to examine the relation of the generation of turbidity according to the outflow of min water. For this research, the region of Jawoon river where is the area of high land vegetable growing in the upper Soyang Reservoir is selected to observe actual floating materials that generate negative nutrition and turbidity of the Reservoir water and the changes of water quality by raining of each month. In addition, the researcher has conducted statistical inspection methods, such as correlation analysis and regression analysis on strength of raining force, and rain continuance time among the elements affecting the outflow of floating materials.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.591-596
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• 2001

The purpose of this paper Is to present and discuss some of evaporation and desiccation observed in laboratory experiments under controlled conditions, and is to improve PTM(Progressive Trenching Method) operating technique. PTM is the technically feasible and economically justifiable dewatering and desiccation technique for dredged material containment areas. A series of laboratory experiments with large model test were carried out to get evaporation rate and strength increase. Surface desiccation of dredged material is basically changed by evaporation characteristics which is controlled by weather and trench type, etc. This study shows that trench depth and rain fall are important factors in desiccation of dredged soft clay.

• Journal of Environmental Science International
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• v.1 no.1
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• pp.29-39
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• 1992

A study on acidity in precipitation was carried out during May 1990 - April 1991 at two sites in Chongwon, Choongbook. We observed variations of pH from 4.0 to 7.0. Annual mean value of pH was 5.21 in the area. In particular, strong acidity of rain fall, pH 4.0 were observed during winter to early spring. Neutral values were observed during June to July and were due to wet deposition of atmospheric pollutants by stationary fronts in the rainy season. Interestingly, acidity of snow observed in winter was neutral and it was weaker than the acidity of rain in winter by a value of 2.0. Discussion is made on meteorological and chemical analyses and seasonal variations of acidity of precipitation.

• Journal of Ginseng Research
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• v.6 no.2
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• pp.168-203
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• 1982

Effects of soil moisture on growth of Panax ginseng, of various factors on soil moisture, and of moisture on nutrition, quality, physiological disorder, diseases and insect damage were reviewed. Optimum soil moisture was 32% of field capacity with sand during seed dehiscence, and 55-65% for plant growth in the fields. Optimum soil moisture content for growth was higher for aerial part than for root and higher for width than for length. Soil factors for high yield in ginseng fields appeared to be organic matter, silt, clay, agreggation, and porosity that contributed more to water holding capacity than rain fall did, and to drainage. Most practices for field preparation aimed to control soil moisture rather than nutrients and pathogens. Light intensity was a primary factor affecting soil moisture content through evaporation. Straw mulching was best for the increase of soil moisture especially in rear side of bed. Translocation to aerial part was inhibited by water stress in order of Mg, p, Ca, N an Mn while accelerated in order of Fe, Zn and K. Most physiological disorders(leaf yellowing, early leaf fall, papery leaf spot, root reddening, root scab, root cracking, root dormancy) and quality factors were mainly related to water stress. Most critical diseases were due to stress, excess and variation of soil water, and heavy rain fall. The role of water should be studied in multidiciplinary, especially in physiology and pathology.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.27-32
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• 2004

With an objective of evolving quantitatively and qualitatively superior bivolitine silkworm hybrid of Bombyxmori L. for tropics with shorter larval duration without compromising on productivity traits, a breeding programme was initiated at this institute during 1997 by utilizing breeding resource material from the institutes Germplasm collection. The breed SD7 is characterized with plain larvae spinning white oval cocoons and SD12 is characterized by sex-limited larval markings spinning white dumb-bell cocoons. After fixation, these breeds along with other newly evolved breeds were subjected for hybrid evaluation in the laboratory. Based on the hybrid studies, the hybrid SD7${\times}$SD12 was selected and evaluated for one year comprising three major sea- sons (6 trials) of tropics viz., Pre-monsoon (characterized by high temperature, low humidity and without any rain fall), Monsoon (characterized by moderate temperature, heavy rain fall with high humidity) and post-monsoon season (characterized by low temperature and low humidity with frequent rain fall) to know the fluctuations in the larval duration. The evaluation studies indicated that the hybrid is having shorter larval duration with productive merits. The hybrid SD7${\times}$SD12 recorded survival percent of 92.74, shell weight of 46.7 cg, shell ratio % of 24.0 and filament length of 1,200 meters with a shorter larval duration of 24 hrs; when compared to productive hybrid CSR2${\times}$CSR5(control). The breeding methodologies and hybrids usefulness for tropics were discussed.

• Proceedings of the KSPS conference
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• 1997.07a
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• pp.228-229
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• 1997

1 Intonation is important. It cannot be ignored. To convince students of the importance of intonation, we can use sentences with two very different interpretations according to intonation. Example: "I thought it would rain" with a fallon "rain" means it did not rain, but with a fall on "thought" and a rise on "rain" it means that it did rain. 2 Although complex, intonation is structured. For both teacher and student, the big job of tackling intonation is made simpler by remembering that intonation can be analysed into systems and units. There are three main systems in English intonation: Tonality (division into phrases) Tonicity (selection of accented syllables) Tone (the choice of pitch movements) Examples: Tonality: My brother who lives in London is a doctor. Tonicity: Hello. How ARE you. Hello. How are YOU. Tone: Ways to say "Thank you" 3 In deciding what to teach, we must distinguish what is universal from what is specifically English. This is where contrastive studies of intonation are very valuable. Usually, for instance, division into phrases (tonality) works in broadly similar ways across languages. Some uses of pitch are also similar across languages - for example, very high pitch may signal excitement or urgency. 4 Although most people think that intonation is mainly about pitch (the tone system), actually accent placement (tonicity) is probably the single most important aspect of English intonation. This is because it is connected with information focus, and the effects on interpretation are very clear-cut. Example: They asked for coffee, so I made them coffee. (The second occurrence of "coffee" must not be accented). 5 Ear-training is the beginning of intonation training in the VeL approach. First, students learn to identify fall vs rise vs fall-rise. To begin with, single words are used, then phrases and sentences. When learning tones, the fIrst words used should have unstressed syllables after the stressed syllable (Saturday) to make the pitch movement clearer. 6 In production drills, the fIrst thing is to establish simple neutral patterns. There should be no drama or really special meanings. Simple drills can be used to teach important patterns: Example: A: Peter likes football B: Yes JOHN likes football TOO A: Mary rides a bike B: Yes JENny rides a bike TOO 7 The teacher must be systematic and let learners KNOW what they are learning. It is no good using new patterns and hoping that students will "pick them up" without noticing. 8 Visual feedback of fundamental frequency with a computer display can help students learn correct patterns. The teacher can use the display to demonstrate patterns, or students can practise by themselves, imitating recorded models.

• Atmosphere
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• v.23 no.3
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• pp.265-273
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• 2013

To investigate properties of cloud and rainfall occurred at Boseong on 10 July 2012, Raindrop Size distributions (RSDs) and other parameters were analyzed using observation data collected by Micro Rain Radar (MRR) and PARticle SIze and VELocity (PARSIVEL) disdrometer located in the National center for intensive observation of severe weather at Boseong in the southwest of the Korean peninsula. In addition, time series of RSD parameters, relationship between reflectivity-rain rate, and vertical variation of rain rates-fall velocities below melting layer were examined. As a result, good agreements were found in the reflectivity-rain rate time series as well as their power relationships between MRR and PARSIVEL disdrometer. The rain rate was proportional to reflectivity, mean diameter, and inversely proportional to shape (${\mu}$), slope (${\Lambda}$), intercept ($N_0$) parameter of RSD. In comparison of the RSD, as rain rate was increased, the slope of RSD became less steep and the mean diameter became larger. Also, it was verified that reflectivities are classified in three categories (Category 1: Z (reflectivity) > 40 dBZ, Category 2: 30 dBZ < Z < 40 dBZ, Category 3: Z < 30 dBZ). As reflectivity was increased, rain rate was intensified and larger raindrops were existed, while reflectivity was decreased, shape (${\mu}$), slope (${\Lambda}$), intercept ($N_0$) parameter of RSD were increased. We expected that these results will lead to better understanding of microphysical process in convective rainfall system occurred during short-term period over Korean peninsula.