• 한국환경과학회지
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• 제24권7호
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• pp.851-864
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• 2015

This study analyzed the climate regime shift using statistical change-point analysis on the time-series tropical cyclone (TC) frequency that affected Japan in July to September. The result showed that there was a significant change in 1995 and since then, it showed a trend of rapidly decreasing frequency. To determine the reason for this, differences between 1995 to 2012 (9512) period and 1978 to 1994 (7894) period were analayzed. First, regarding TC genesis, TCs during the 9512 period showed a characteristic of genesis from the southeast quadrant of the tropical and subtropical western North Pacific and TCs during the 7894 period showed their genesis from the northwest quadrant. Regarding a TC track, TCs in the 7894 period had a strong trend of moving from the far east sea of the Philippines via the East China Sea to the mid-latitude region in East Asia while TCs in the 9512 period showed a trend of moving from the Philippines toward the southern part of China westward. Thus, TC intensity in the 7894 period, which can absorb sufficient energy from the sea as they moved a long distance over the sea, was stronger than that of 9512. Large-scale environments were analyzed to determine the cause of such difference in TC activity occurred between two periods. During the 9512 period, anomalous cold and dry anticyclones were developed strongly in the East Asia continent. As a result, Korea and Japan were affected by the anomalous northerlies thereby preventing TCs in this period from moving toward the mid-latitude region in East Asia. Instead, anomalous easterlies (anomalous trade wind) were developed in the tropical western Pacific so that a high passage frequency from the Philippine to the south China region along the anomalous steering flows was revealed. The characteristics of the anomalous cold and dry anticyclone developed in the East Asia continent were also confirmed by the analysis of air temperature, relative humidity and sensible heat net flux showing that most regions in East Asia had negative values.

• Asian-Australasian Journal of Animal Sciences
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• 제13권12호
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• pp.1659-1666
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• 2000

Two experiments were conducted to determine the effects of Leucaena leucocephala (leucaena) and Gliricidia sepium (gliricidia) supplementation on intake, digestion, outflow rates, microbial protein yield and live-weight changes in sheep fed with ammoniated rice straw (ARS). In experiment 1, three rumen cannulated Japanese Corriedale wether (mean body weight of 35.6 kg) in $3{\times}3$ Latin Square Design were used. Animals were fed ad libitum ARS alone, or supplemented with 200 g of either leucaena or gliricidia. In experiment 2, twenty-four growing native Philippine sheep with average body weight of $13.5{\pm}0.25kg$ were used in a completely randomized design (CRD) and offered similar diets to those of experiment 1. Supplementation increased total dry matter intake and nutrient digestibility except for fiber (p<0.05) without affecting ARS consumption. Nitrogen balance revealed that absorbed and retained N was significantly higher in leucaena and gliricidia. The significant improvement in N utilization and more digestible OM intake brought about by the inclusion of leucaena and gliricidia to ARS resulted in increased (p<0.05) microbial N yield. Efficiency of microbial N supply in supplemented group was not significantly different, but higher (p<0.05) than the 24.92 g N/kg DOMR for ARS group. Liquid outflow rate was 7.8 and 6.8 %/h, while the solid phase of rumen digesta was 4.4 and 3.8 %/h for the leucaena and gliricidia group respectively, which were significantly higher than 5.30 and 2.50 %/h in the control diet. The increase in total DMI resulted to higher (p<0.01) growth performance and efficient feed utilization. Average daily gain (ADG) was 19.3, 34.6 and 33.9 g/d for the ARS, leucaena and gliricidia respectively. It is therefore concluded that addition of leucaena and gliricidia to ARS in could increase nutrient intake and digestibility, subsequently improving N utilization and livestock performance.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.321-321
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• 2017

Water availability in rainfed lowlands (RFL) is strongly affected by climate change. In RFL, rice plants are exposed to soil moisture fluctuations (SMF) but rarely to simple progressive drought as widely believed. Typical RFL field is characterized by a about 5-cm thick high bulk density hardpan layer underneath the cultivated layer at about 20 cm depth that impedes deep root development. Root system has the ability to develop in response to changes in SMF, known as phenotypic plasticity. We hypothesized that genotypes that can adapt to RFL have root plasticity. The roots can sharply respond to re-wetting after drought period and thus penetrate the hardpan layer when the hardpan is wet and so becomes relatively soft, and thus access water under the hardpan. This study aimed to identify CSSLs derived from a cross between Sasanishiki and Habataki which adapted to such RFL conditions. We used 39 CSSLs together with the parent Sasanishiki, which were grown in hydroponics and pot under transient soil moisture stresses (drought and then rewatering), and compared with continuously well-watered (WW) (control) up to 14 days after sowing (DAS), and 20 DAS, respectively. Based on the results of hydroponics and pot experiments, we selected a few lines, which were grown in the soil-filled rootbox with artificial hardpan layer and without artificial hardpan. For the rootbox without artificial hardpan, plants were grown under WW and transient soil moisture stresses for 49 DAS. While the rootbox with artificial hardpan, the plants were grown under WW (control) and SMF (WW up to 21 DAS, 1st drought (22-36 DAS), rewatering (37-44 DAS), and followed by 2nd drought (45-58 DAS)). Among the 39 CSSLs, only CSSL439 (SL39) consistently showed significantly higher shoot dry weight (SDW) than Sasanishiki under transient soil moisture stress conditions as well as SMF conditions in all the experiments. Furthermore, under WW, SL39 consistently showed no significant differences from Sasanishiki in shoot and root growth in most of traits examined. SL39 showed significantly greater total root length (TRL) than Sasanishiki under transient soil moisture stress, which is considered as phenotypic plasticity in response to rewatering after drought period. Such plastic root development was the key trait that effectively contributed to root elongation and branching during the rewatering period and consequently enhanced the root to penetrate hardpan layer when the soil penetration resistance at hardpan layer reduced. In addition, using the rootbox with artificial hardpan layer ($1.7g\;cm^{-3}$, heavily compacted), SL39 showed greater root system development than Sasanishiki under SMF, which was expressed in its significantly higher TRL, total nodal RL, and total lateral RL at hardpan layer as well as at below the hardpan layer. These results prove that SL39 has plasticity that enables its root systems to penetrate hardpan layer in response to rewatering. Under SMF, such root plasticity contributed to its higher gs and Pn.

• 한국콘텐츠학회논문지
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• 제16권4호
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• pp.153-169
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• 2016

본 연구는 필리핀 한류 조사를 바탕으로, 필리핀의 한국에 대한 인식과 한국문화수용의 특징을 살펴보고 필리핀의 한류수용의 특징과 배경을 파악하는데 목적이 있다. 이를 위해, 본 연구는 필리핀 현지 대학생과 한국에 거주하는 필리핀인을 대상으로 FGI 조사, 문헌연구 및 통계자료 분석을 실시하였다. 필리핀과 한국은 한류를 매개로 교류를 한층 강화하고 있지만, 한편 코피노 및 한국인 상대 범죄 등 갈등요소도 지속적으로 늘어나고 있다. 따라서 필리핀인을 대상으로 한 한류연구는 향후 양국간 사회문화적 관계를 예측하는데 있어 중요한 변수가 된다. 본 연구는 필리핀 현지 대학생과 한국 거주 필리핀인의 한류 문화소비의 인식, 태도, 행동에는 차이가 있었으며, 두 집단 모두 '한국인과의 접촉경험'이 한국과 한국문화를 인지하는데 매우 중요한 요소임을 나타내었다. FGI 조사 참여자들은 한국드라마 관람, 한국어 공부, 그리고 주변 한국인과의 관계형성을 위해 노력하였다. 필리핀과 한국의 관계가 향상되기 위해서는 한류가 한국문화의 특징뿐만 아니라 보편적 문화로서의 가치를 높여야 할 것이다. 이를 통해, 필리핀 문화에 대한 이해를 높이고 문화적 관계를 발전시키기 위해, 향후 한국문화의 전반을 아우르는 한류 3.0이 현지의 일상문화로 뿌리내릴 수 있도록 노력해야 할 것이다.

• Ocean and Polar Research
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• 제31권1호
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• pp.121-131
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• 2009

In an effort to better understand the physiological and ecological differences between warm and cold water copepod species in Korean waters using lipid contents and compositions, two species of copepods (Pleuromamma sp. as a warm water species and Neocalanus plumchrus as a cold water species) were collected from the Northwest Pacific and East Sea/Sea of Japan, respectively. The cold water species showed two fold higher lipid contents than the warm water species (11% vs. 5% of dry weight). Wax esters, known as one of the major storage lipid classes, were found to be the dominant lipid class (accounting for 64% of total lipids) in the cold water species, whereas, in the warm water species, phospholipids, which are known as membrane components, were the dominant lipid class (accounting for 43% of total lipids),with a trace amount of the storage lipids as a form of triacylglycerols (${\leq}1%$ of total lipids). With regard to the fatty acid compositions, saturated fatty acids (SAFA), especially 16:0 (about 30% of total fatty acids), were most abundant in the warm water species, whereas the polyunsaturated fatty acids (PUFA), particularly eicosapentaenoic acid (EPA : 20:5(n-3)) (${\geq}16%$ of total fatty acids), were most abundant in the cold water species. Among the neutral fraction of lipids, phytol, originating from the side chain of chlorophyll and indicative of active feeding on phytoplankton, was detected only in the warm water species. Significant quantities of fatty alcohols were detected in cold water species, particularly long-chain monounsaturated fatty alcohols (i.e. 20:1(n-9) and 22:1(n-11)), which are well known to abound in cold water herbivorous copepods. However, only trace amounts of short-chain fatty alcohols were detected in the warm water species. Twelve different kinds of sterols were detected in these copepod species, with cholest-5-en-$3{\beta}$-ol (cholesterol) and cholesta-5, 24-dien-$3{\beta}$-ol (desmosterol) dominating in cold and warm water species, respectively. In addition, for the warm water species (Pleuromamma sp.), we assessed the latitudinal gradients of lipid contents and compositions using samples from three different latitudinal regions (Philippine EEZ, Japan EEZ, and the East China Sea). Although no latitudinal gradients of lipid contents were detected, the lipid compositions, particularly dietary fatty acid markers, varied significantly with the latitude. The findings of this study confirm that the distribution of lipid contents and compositions in copepods may not only indicate their nutritional condition and diet history, but may also provide insights into their living strategies under different environmental conditions (i.e., water temperature, food availability).

• 환경생물
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• 제25권4호
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• pp.349-355
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• 2007

지렁이과 (family Megascolecidae) 왕지렁이속 (genus Amynthas) 그룹을 rDNA ITS 유전자를 이용하여 계통 유연관계를 알아보고자 하였다. 2과 10속에서 26종의 DNA 염기서열을 이용하여 종간 계통적 유연관계를 MP (Maximum Parsimony), NJ (Neighbor Joining), QP (Quartet Puzzling)로 계통도를 작성하였다. 염기서열이 확보된 Megascolecidae (지렁이과)의 국내외 26종에 대한 계통 분석은 위 3개의 알고리즘 모두 동일한 5개의 그룹으로 나뉘는 것을 확인하였다. 또한 Amynthas 속은 크게 한국산 그룹과 필리핀산 그룹으로 구분되었다. 첫 번째 그룹, Amynthas jirensis, A. agrestis, A. gucheonensis, A. sopaikensis, A. bubonis, A. multimaculatus, A. koreanus, A. dageletensis, A. heteropodus, A. odaesanensis, Pontoscolex sp., Pheretima sp. 1와 다른 그룹, Dendropheretima banahawensis. Amynthas halconensis, A. isarogensis, A. mindrooensis, Pithemera sp. 2, Pithmera sp. 1, and Pleionogaster sp.이다. 이는 ITS 유전자가 속간의 차이를 보여주는 것보다 동일한 속이라 하더라도 지리적 차이에 따른 환경의 영향을 받았음을 알 수 있다. 즉 형태적 분화가 이루어졌다고 하더라도 유전적으로는 동질성을 나타내고 있음을 알 수 있다. 형태적 특징에 의한 명백한 차이는 구분되지 않았다.

• 한국토양비료학회지
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• 제7권3호
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• pp.127-135
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• 1974

The samples were taken from the following localities previously classified as "Akiochi" area: Yangpyung, Puchun, and Pyungtaik, all of Kyonggi-do province. Five soil profiles were described in the field, and taken to the laboratory for physical and chemical analysis and mineralogical analysis by X-ray diffraction. The predominant clay minerals consist mainly of illite, vermiculite, chlorites and intergrade with vermiculite, and kaolinite. Illite or mica was found present in all samples and in all horizons. This was identified by the 9.83 to $10{\AA}$ (0.01) and $3.32{\AA}$ (003) basal reflections, Interhorizontal variations in mineral content and crystallinity are illustrated in their respective Xray diffractogram. Comparing the peak intensity, of the $14{\AA}$, $10{\AA}$ and $7{\AA}$ indicated the degree of weathering from the surface to the lower horizons. In general, the weathering of illite on the surface produced less pronounced $10{\AA}$ and $14{\AA}$ peak as compared to the lower horizons. The same may be said with kaolinite. On K-saturation, the $14{\AA}$ peak broadening on the low angle side was observed. This is interpreted to be due to chlorization. Heat treament from $100^{\circ}C$, $200^{\circ}C$, $400^{\circ}C$, $600^{\circ}C$, and $800^{\circ}C$. caused significant changes in the different diffractograms. Heating caused collasped of the $14{\AA}$ to $10{\AA}$ and the appearance of scattered peaks between $10-14{\AA}$. This is interpreted to the presence of vermiculite chlorite intergradient. The complete collapse of the $14{\AA}$ at $800^{\circ}C$ to $10{\AA}$ with increased intensity was attributed to the preservce of vermiculite. The principal difference among the clay minerals in each horizon is the concomitant increase and decrease in intensity with depth of the $14{\AA}$, $10{\AA}$ and $7{\AA}$ diffraction spacings. Apparently the weathering of illite ($10{\AA}$) is resulting in the formation of vermiculite ($14{\AA}$) and the interstratified material being an intermediate stage and the beginning of the formation of vermiculite. Some broadening- in the 17 to $18{\AA}$ was observed in Puchun-1 Pyungtaik-1 and Pyungtaik-2 specially so in the lower horizon in the Ca or Mg-saturated sample. Heated treatment tend to shift this peak to $14{\AA}$ indicating the presence of regular layering of the interstratified complex. The high amount of extractable aluminum and iron coupled with low exchange capacity indicate that iron and aluminum plays an important role in the weathering of these soils and is responsible to the low exchange capacity, high acidity and high phosphate absorptive capacity. The results presented substantiated the weathering sequence of Jackson in that mica ${\rightarrow}$ vermiculite ${\rightarrow}$ chloritezed vermiculite ${\rightarrow}$ kaolinite.

• 한국소음진동공학회논문집
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• 제19권1호
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• pp.64-75
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• 2009

최근 조선소에서 고출력 디젤엔진의 요구에 의해서 초대형 저속 2행정 디젤엔진이 개발되었으며, 연속최대출력이 $8{\sim}14$실린더를 갖는 10만 마력 이상의 엔진을 사용할 수 있게 되었다. 이러한 엔진들은 열효율, 운전에 대한 신뢰성, 강인성 및 기동성은 뛰어나지만 크랭크축을 포함한 추진축계에서 높은 비틀림진동을 유발한다. 따라서 이 연구에서는 엔진설계자의 입장에서 비틀림진동을 줄이기 위하여 튜닝 비틀림진동 댐퍼를 갖는 추진축계의 비틀림진동을 이론적으로 검토하였으며 실험모델인 12K98MC엔진과 12RT-flex엔진에서 튜닝댐퍼의 성능과 동적거동을 확인하고 있다.

• 한국응용곤충학회지
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• 제38권2호
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• pp.157-164
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• 1999

먼지응애류인 벼먼지응애(신칭, Steneotarsonemus spinki Smiely 1967)는 쌀생산국인 태국, 필리핀, 중국, 대만 등에서 쌀의 중요한 해충이다. S. spinki가 국내에서 처음으로 환경조절온실에서 재배중인 쌀에서 발견되었다. 응애 피해를 입은 쌀은 이삭에서 기형을 나타내었으며 잎집내부 표면의 갈변증상, 쌀알의 표면 갈변증상 등을 나타내었다. S. spinki암컷의 체장은 263.0$\mu\textrm{m}$(246.5~$284.6\pm$12.2), 체폭은$ 92.4\mu\textrm{m}$(79.5~$104.9\pm$7.6)였으며 전체적인 모양은 난형으로 중앙부위가 가장 폭이 넓었다. 채색은 연한 황색이었다. 다리는 잘 발달되어 있었으며 암컷 제4각 끝은 채찍모양의 강모로 이루어진 전형적인 먼지응애류의 특징을 가지고 있었다. 수컷 체장은 196.5$\mu\textrm{m}$(176.5~222.8$\pm$15.8), 체폭은 109.3$\mu\textrm{m}$ 98.6~$117.7\pm$6.4)였으며 전체적인 모양은 길쭉하고 전동체부 중앙부가 가장 체폭이 넓었다. 내돌기 III은 내돌기 IV보다 전방으로 신장되어 있었다. 제4각퇴절은 커다란 안쪽귀가 발달되어 있었으며 안쪽 및 바깥쪽 강모는 같은 길이로 짧게 잘 발달되어 있었다. 부절 발톱은 강하고 복부쪽으로 굽어 있었다.

• 한국동물학회지
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• 제8권2호
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• pp.89-127
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• 1965

1. This report is on the outcome of observation made up the breeding process of Narcissus flycatcher, Muscicapa narcissina zanthopygia, using 15 ness-boxes at Seoul and Kwang Nung Experimental forest in 1964, and the relevant feeding habit was studied by the collar method of wrapping the necks of thenestlings for 50-60 minutes or more in some cases from 1963 to 1964. 2. The Narcissus flycatcheris a common summer resident throughout Korea arriving at the end of April. The earliest data of arrival of this species in Seoul, is April 26, 1964. They migrate southward from the later part of September to early part of October. 3. In a week after their arrival , they start to build nest after a brief courtship. Male and female prepare their nest ina nestboxes in 4 or 5 days. Nests are usually found in the moss, which provide definite frame-work. The inner side of the nest is usually composed of roots of Gramineae or leaves of pine, oak or other broad leave tree. 4. The laying period is generally from the later part of April to the middle of June : and the number of eggs laid is from 3 to 8 , therefore 5 in average : eggs are pink with traces of milky yellow blending of light auburn and orange red spots and chicken-egg-like in shape. 5.The incubation takes place for 7-12 days from the middle part of May to the middle of June, in the order of male and female . The hatching rate tends to increase in proportion to clutch size. 6. The feeding period usually lasts 15 days in average from the early part of June to the middle of July and the feeding urge tends to increase in proportion to brood size. 7. The animals invading into their nest-boxes are red ants, chipmunks, bees , barkbeetles and philippine red-tailed shirkes, etc. 8. On the basis of analysis covering 714 birds in 31 nests, the food they consumed during the nesting period of nestlings were mostly of animal matters composing of : insect larvae form-39. 88% insect adult form 36.26%, insect pupae-0.19%, spider-17.75% and other animal matters 5.92% , Besides a small amount of plant pieces were found . As to the insect larvae, Lepidoptera was the largest in the content followed by Hymenoptera , Orthoptera and Coleoptera. As to the insect adult, Diptera was the largest in the content followed by Coleoptera, and Hymenoptera. In view of forest protection, noxious insect was of 69.38%, useful insect 4.39%, and spider 17.75%. 9. The rich assortment of its food, the ability of acquiring various insect (adults as well as larvae), its destruction of great numbers of harmful insects , and its quick assimilation artificial nesting with the nest-boxes of 2.5-3cm entrance hole employed, allow us to conclude that the flycatcher may be successfully employed in the elimination of fores pests. The above results are only that part obtained near Seoul in the middle of Korea, however, if we would extend the scheme to other broad areas using similar techniques, the nest-boxes could not only be well used by the birds, but also it would help to prevent the increase of harmful. insects.