This paper describes the measurement of the underwater noises produced by the engine vibration around the engine room of stern trawler MIS Sae-Ba-Da(2275GT, 3,600 PS) and pole kner M/S Kwan-Ak-San (243 GT, 1000 PS) while the ship is stopping. The underwater noise pressure level was measured with the underwater level meter of which measuring range is 100 to 200 dB(re bLPa). A and B denotes the maximum pressure level measured at right beneath the bottom of the engine room, while the main engine of the Sae-Ba-Da revoluted at 750 and 500 rpm, respectively. C denotes that of the main engine of the Kwan-Ak-San revoluted at 350 rpm, and D that of the generator of the Sae-Ba-Da revoluted at 720 rpm. Thus A, B, C and D were set for the standard sound source for the experiment. The results obtained are as follows: 1. The noise Pressure level at A, B, C and D were 170.5,165,153 and 158dB, respectively. 2. When the check points distanted vertically 1, 10, 20, 30, 40, 50m from the sound source, the underwater noise presure levels were 170.5, 155, 148, 144 and 138 dB and the directional angle was 116\ulcorner in case of A. 3. The sound level attenuated at the rate of 20dB per 10" meters of the horizontal distance from the sound sources. 4. The frequency distribution of the noise was 100Hz to 10KHz and predominant frequency was 700 to 800Hzminant frequency was 700 to 800Hz

본 연구는 희귀 식물인 거문도닥나무를 대상으로 종자 및 삽목번식을 통하여 효율적인 번식방법을 규명하고자 하였다. 실험 결과 종자번식은 실내, 실생 번식 모두 발아율에서 유의성이 나타났다. 저장 종자는 저온 습윤의 경우 항온 20℃ 효과를 보였으며, 변온 처리에서는 발아율이 대체적으로 낮게 나타나 종자 번식에서 거문도닥나무는 습윤 저장 후 항온 20℃에서 발아율 이 높았으며, 실생 번식은 노천매장에서 종자를 번식하는 것이 가장 효과적인 것으로 실험에서 확인되었다. 삽목번식의 관수 시설에 따라 캘러스 형성, 뿌리 수 등 발근율을 확인한 결과 미 스트 관수 비닐하우스에서 녹지의 중간, 아랫부분에서 10.0%가 발근 하였고, 숙지 삽목은 모두 발근 하지 않았다. 특히, 뿌리 수와 뿌리 길이가 각각 5개, 112.6 ㎜로 미스트 관수 비닐하우스에서 월등히 높은 결과를 보여 거문도닥나무 삽목은 습도에 영향을 미치는 것을 알 수 있었다. 전처리에 따른 녹지 삽목은 미스트 관수 비닐하우스에서 거문도닥나무의 중간 부분, 아랫부분을 대상으로 삽목을 실험한 결과 캘러스 형성률, 발근율, 뿌리 수, 뿌리 길이 모두 유의성이 있었다. 녹지 삽목은 평균 발근 율이 23.7%로 저조하였으며, IBA 500 ppm, IBA 1000 ppm, NAA 2000 ppm에서 발근 좋은 것으로 나타났다. 이에, 녹지 삽목의 아랫부분보다 중간 부분이 삽목번식에 효과가 있는 것으 로 실험에서 확인되었다. 특히, 숙지 삽목은 평균 발근율이 11.9%로 녹지 삽목에 비해 저조하였는데 이는 숙지 부분의 잎이 거의 없으며, 잎이 있는 때는 조기에 떨어져 삽목에 영향을 준 것으로 판단된다.

We have developed an algorithm for tracking coronal mass ejection (CME) propagation that allows us to estimate CME speed and its arrival time at Earth. The algorithm may be used either to forecast the CME’s arrival on the day of the forecast or to update the CME tracking information for the next day’s forecast. In our case study, we successfully tracked CME propagation using the algorithm based on g-values of interplanetary scintillation (IPS) observation provided by the Institute for Space- Earth Environmental Research (ISEE). We were able to forecast the arrival time (Δt = 0.30 h) and speed (Δv = 20 km/s) of a CME event on October 2, 2000. From the CME-interplanetary CME (ICME) pairs provided by Cane & Richardson (2003), we selected 50 events to evaluate the algorithm’s forecast capability. Average errors for arrival time and speed were 11.14 h and 310 km/s, respectively. Results demonstrated that g-values obtained continuously from any single station observation were able to be used as a proxy for CME speed. Therefore, our algorithm may give stable daily forecasts of CME position and speed during propagation in the region of 0.2–1 AU using the IPS g-values, even if IPS velocity observations are insufficient. We expect that this algorithm may be widely accepted for use in space weather forecasting in the near future.

This study investigated a suitable method that could be applied for Asian chain fern [Woodwardia japonica (L. f.) Sm.] to propagate gametophytes and promote sporophyte formation. The gametophytes used in all experiments were obtained from germinated spores in vitro and were subcultured at 8-week intervals. The most appropriate media for gametophyte propagation was identified by culturing 300 ㎎ of gametophyte in Murashige and Skoog (MS) basal medium (1/8, 1/4, 1/2, 1, 2), and Knop medium for 8 weeks. As a result, fresh weight of the gametophyte was increased by 56.7-fold on MS medium. Moreover, antheridium formation as well as gametophyte growth was improved on MS medium, especially. To improve the sporophyte formation ex vitro, 1.0 g of gametophyte was ground with distilled water and spread on eight combinations onto four different culture mediums, such as bed soil, peat moss, perlite and decomposed granite. Then generation and growth of sporophytes were investigated after cultivation for 10 weeks. As a result of this experiment, peat moss had a promotive effect of sporophyte formation at single-use and mixed culture soils. In particular, a mixture of bed soil, peat moss and perlite in a 1:1:1 ratio (v/v/v) led to the accelerated formation (782.5 ea/pot) and the frond growth of sporophytes. This included increases in length and width of fronds. However, promotive effect of gametophyte growth and sporophyte formation was not found at single-use and treatment with high ratio of bed soil.

본 연구는 진퍼리고사리의 전엽체 증식을 위한 배지를 선발하고, 포자체 증식을 위한 적정 배양토를 구명하여 대량생산 체계를 구축하고자 수행되었다. 전엽체 증식연구는 배지종류(1/4, 1/2, MS 배지, Knop 배지), sucrose (0, 1, 2, 3, 4%),의 농도를 달리한 배지에 전엽체 300 ㎎를 각각 접종하여 8주간 배양한 후 전엽체의 생육을 비교하였다. 포자체 형성 연구는 분쇄한 전엽체를 인공토양위에 접종하여 수행하였다. 인공토양은 원예상토, 펄라이트, 마사토의 비율을 다르게 조성하거나 원예상토단 용으로 사용했다. 그 후 접종한 전엽체를 12주간 배양한 다음 포자체 형성 및 생육을 조사하였다. 본 연구의 결과, 기내 전엽체는 2% sucrose를 첨가한 MS 배지에서 생체중과 생육이 가장 우수하였다. 포자체 형성을 위한 배양토 조성 실험에서는 원예상토:펄라이트 2:1(v:v)와 원예상토:마사토 2:1(v:v) 처리구에서 포자체의 형성이 가장 많았으며, 전반적인 생육은 원예상토:마사토 2:1(v:v)가 우수하였다.

Background : Ligusticum chuanxiong Hort is a perennial herb of the Umbelliferae family and an important traditional oriental medicinal plant. The compounds contained in L. chuanxiong can be divided into five kinds, essential oil, alkaloids, phenolic acids, phthalide lactones, and other constituents. These compounds have cardiovascular and cerebrovascular effects, antioxidants, neuroprotection, anti-fibrinolytic, antidotes, anti-inflammatory and antitumor activities. In this study, we anticipated to establish the in vitro propagation system of L. chuanxiong, which is a high economic value as medicinal herb, by plant tissue culture to solve the problem of root stocks contamination. Methods and Results : The whole study was carried out in the department of Herbal crop research, Eumseong, RDA. In this study, L. chuanxiong nodes was used as an explant and it was surface sterilized by 2% sodium hypochlorite for 1 minutes, then washed with ddH2O several times. Further the surface sterilized nodes were placed on MS basal media. Multiple shoots were induced on MS, SH, WPM media with 0.1 - 2 ㎎/ℓ auxin (NAA, IBA) and cytokine (BA). In this study we obtained 4.6 multi-shoots per an explant, and growth of the shoot was also favorable in the presence of 1.0 ㎎/ℓ BA. Subsequent transfer of these regenerated shoots on 1/2 MS media resulted in root formation. The rooted plantlets were able to grow in soil after 3 weeks of acclimatization. Conclusion : The optimal conditions for in vitro propagation of L. chuanxiong were established through this experiment.

Background : Glycyrrhiza uralensis Fischer is one of most important medicinal (Glycyrrhizae radix) herbs in traditional oriental medication and they are also important commercial products used worldwide in sweetening and flavoring. They contain the similar compounds, such as the triterpenoid saponins and flavonoids. Therefore, it is necessary to develop more efficient and sustainable methods for the production of G. uralensis Fischer and its medicinal constituents. This study was accomplished to investigate the effect of medium composition on in vitro propagation and plantlet regeneration from nodal explants of G. uralensis Fischer, and to establish a reliable protocol for micropropagation. Methods and Results : Young and actively growing stem segments were excised from adult plants of new cultivar ‘manju’. They were cut into a 1cm nodal segments with single node after sterilization, and cultivated in the different medium supplemented with various plant growth regulators for two weeks. For shoot multiplication, one-node stem segments, approximately 1 ㎝ in length, were taken from in vitro derived shoots and subcultured. After four weeks of culture, the efficacy of each medium on shoot proliferation and growth was determined, and these shoots were transferred onto medium with different auxin hormones for rooting. Conclusion : After seven to ten days of culture, shoots began to emerge from axillary buds. They showed a vigorous growth and elongation in multiplication medium. During culture period, in vitro cultured plantlets showed significantly different responses to the respective medium with different plant growth regulators. Our experiments confirmed that in vitro growth and multiplication of palntlets could depend on its reaction to the different medium composition, and this micropropagation techniques could be a useful system for healthy and vigorous plant production.

Background : Sea buckthorn (Hippophae rhamnoides) is a multipurpose small tree with unique berries of high nutritional and pharmaceutical values has wide spread distribution from Eurasia to South east Asia. In recent times the medicinal benefits of vitamin tree are inclining, hence, efforts were taken to propagate them in vitro to exploit their medicinal property. Methods and Results : The tissue culture potential of them was investigated for the ability to induce shoot organogenesis in leaf explant, and induction of direct somatic embryogenesis from leaf tissue. Moreover, we also determined the effective induction medium for callus and somatic embryo production from H. rhamnoides. To induce the callus form leaf tissue, several phytohormone combinations such as α-naphthalene acetic acid (NAA) and 6-benzyladenine (BA), 2,4-Dichlorophenoxyacetic acid (2,4-D) and 6-benzyladenine (BA), and Kinetin (K) were tried with the Murashige and Skoog (MS) as well as woody plant medium (WPM). In MS basal medium, the combination of 2,4-D and K showed the best callus induction rate of 71%, whereas in WPM basal medium the combination of NAA and BA showed the best callus induction rate of 91%. The adventitious root induction form callus was also attempted by using MS and B5 medium with the phytohormone combinations of IBA 1 – 5 g/ℓ. In MS medium, root was induced only at 4 g/ℓ of IBA and 64%, 51% and 55% root induction results were obtained at 3 g/ℓ, 4 g/ℓ and 5 g/ℓ in B5 basal medium, respectively. The somatic embryos were induced only in half strength MS with the triple phytohormone ratio of 2:1:2 of NAA, BA, and K. Conclusion : The in vitro propagation of sea buckthorn was successfully employed by generating callus, adventitious roots as well as the induction of somatic embryos form the leaf tissues derived callus. Our results provided a valuable addition to the utilization of H. rhamnoides thus enabling their propagation.

가뭄은 여러 가지 요인에 의해 복합적으로 발생하는 현상으로 자연적 원인과 인위적 원인으로 구분할 수 있다. 우리나라는 기후학적 특성상 여름철에 태평양 고기압의 발달 시기가 빠르거나 평년보다 강하면 장마 기간이 짧아져 자연적인 원인에 의해 가뭄이 발생한다. 가뭄은 발생과정과 피해 영향에 따라 기상학적, 농업적, 수문학적, 사회경제적 가뭄으로 구분할 수 있으며 직 ․ 간접적으로 다른 가뭄에 영향을 미친다. 가뭄의 종류가 기상학적 가뭄에서 농업적 가뭄 혹은 기상학적 가뭄에서 수문학적 가뭄으로 변화되는 현상을 가뭄 전이라 한다. 본 연구에서는 국내의 가뭄 전이 발생여부와 발생 패턴을 검토하기 위해 수문기상 정보를 이용하여 기상학적 가뭄에서 농업적 가뭄으로의 전이 관계를 분석하였다. 가뭄 전이 발생 현황 및 특성 분석을 위해 가뭄 발생의 유형을 5가지로 구분하였으며, 유형에 따라 가뭄 전이가 발생하지 않거나 최대 3개월까지 지체되는 것을 확인하였다. 향후 더 많은 가뭄 지표들과의 분석을 통해 가뭄 전이 관계를 일반화한다면 기상학적 가뭄 발생 시 농업적 가뭄 예측을 위한 인자로 활용할 수 있을 것으로 기대된다.

대형 용접 구조물에 대한 피로설계 수명의 예측은 일반적으로 Palmgren Miner과 등가손상도 방법 또는 선형누적손상도 방법을 사용한다. 또한 용접 구조물에서 피로 균열이 발생되면 잔존 수명은 S-N 곡선과 선형 파괴역학에 기초하여 예측되고 있다. 본 연구에서는 면외거 셋 용접이음의 3차원 피로균열 진전거동과 피로수명을 예측하기 위하여 피로 시험을 실시하였다. 면외거셋 용접이음의 3차원 피로균열진전 해석은 NX NASTRAN 및 FRANC3D를 이용하여 유한요소 해석을 실시하였다. 면외거셋 용접이음의 균열 형상비, 초기균열 크기 및 응력비에 미치는 영향을 검토하기 위하여 피로균열진전 해석을 실시하였다. 또한 초기균열크기, 균열 형상비와 응력비의 변화에 따른 3차원 피로균열진 전 해석 결과와 피로시험결과를 비교하였다. 피로균열진전 해석결과, 피로균열 진전속도와 응력확대계수와의 관계에서 피로시험과 유사하게 나타남을 확인하였으며, 면외거셋 용접이음의 피로수명을 추정할 수 있음을 확인하였다.

Halo coronal mass ejections (CMEs) originating from solar activities give rise to geomagnetic storms when they reach the Earth. Variations in the geomagnetic field during a geomagnetic storm can damage satellites, communication systems, electrical power grids, and power systems, and induce currents. Therefore, automated techniques for detecting and analyzing halo CMEs have been eliciting increasing attention for the monitoring and prediction of the space weather environment. In this study, we developed an algorithm to sense and detect halo CMEs using large angle and spectrometric coronagraph (LASCO) C3 coronagraph images from the solar and heliospheric observatory (SOHO) satellite. In addition, we developed an image processing technique to derive the morphological and dynamical characteristics of halo CMEs, namely, the source location, width, actual CME speed, and arrival time at a 21.5 solar radius. The proposed halo CME automatic analysis model was validated using a model of the past three halo CME events. As a result, a solar event that occurred at 03:38 UT on Mar. 23, 2014 was predicted to arrive at Earth at 23:00 UT on Mar. 25, whereas the actual arrival time was at 04:30 UT on Mar. 26, which is a difference of 5 hr and 30 min. In addition, a solar event that occurred at 12:55 UT on Apr. 18, 2014 was estimated to arrive at Earth at 16:00 UT on Apr. 20, which is 4 hr ahead of the actual arrival time of 20:00 UT on the same day. However, the estimation error was reduced significantly compared to the ENLIL model. As a further study, the model will be applied to many more events for validation and testing, and after such tests are completed, on-line service will be provided at the Korean Space Weather Center to detect halo CMEs and derive the model parameters.

최근 우리나라에서 빈번하게 발생되는 가뭄으로 인하여 많은 피해가 발생하고 있으며, 이에 대한 사전대응의 필요성이 커지고 있다. 가뭄에 대한 효과적인 사전대응을 위해서는 신뢰성 있는 가뭄 예측 정보가 필수적이다. 본 연구에서는 수문학적 가뭄에 대한 확률론적 예측을 수행하기 위하여 가뭄의 전이현상을 베이지안 네트워크 모형에 반영하였다. 가뭄의 전이현상을 고려한 베이지안 네트워크 기반의 가뭄 예측 모형(PBNDF)은 과거, 현재, 미래에 대한 다중 모형 앙상블 예측결과와 가뭄전이 관계를 결합하여 새로운 수문학적 가뭄 예측 결과를 생산하도록 구축되었다. 본 연구에서 PBNDF 모형은 파머수문학적 가뭄지수를 활용하여 낙동강 유역의 10개 지점을 대상으로 가뭄을 확률적으로 예측하는데 적용되었다. PBNDF 모형의 ROC 분석 결과 ROC 점수가 0.5 이상의 유의한 결과를 나타내 실제 예측 모형으로 활용가능하다는 것을 확인할 수 있었다. 또한, 기존에 개발된 모형(지속성 예측, 베이지안 네트워크 예측 모형)과 평균제곱오차의 제곱근(RMSE), 기술 점수(SS)를 활용하여 비교를 수행하였으며, 그 결과 PBNDF 모형의 RMSE는 상대적으로 낮은 값을 가지며, SS는 약 0.1~0.15 정도 높은 것으로 나타나 예측성능이 향상되었다는 것을 확인할 수 있었다.

Background : The practice of keeping the medicinal herbs at room temperature causes many problems, but due to lack of sufficient field research and study, it is difficult to improve related regulations and safety management. Methods and Results : The Cnidium Rhizome and Angelica gigas Root were inoculated with Lasioderma serricorne F. and incubated at 28℃ for 2.5 months and 5 months. After five months, the number of Lasioderma serricorne F. in Cnidium Rhizome increased from 30 to 1,429 (about 47 times). In the same period, the number of insects in Angelica gigas Root increased from 30 to 663 (about 22 times). Due to the rapid increase in pest population, hygiene deteriorated, changes in the active ingredient and appearance quality of the herbal medicines, which greatly damaged the value of the herbal medicine. Conclusions : These results show that current regulation requiring only sealing and not specifying the storage temperature do not guarantee quality safety. Therefore, it is necessary to establish appropriate preservation standards and improve management regulations in order to preserve safety.

It is important to accurately predict natural frequencies of a cracked beam for damage assessment. The damage can be confirmed through the comparison of the natural frequencies of an intact beam to those of a target beam. This study formulates the natural frequencies of a cracked beam from wave propagation perspective. This formulation results in an explicit characteristic equation with respect to wave number through neglecting the evanescent wave modes traveling from long distance. The proposed method is validated through an numerical example in which several natural frequencies computed by the proposed method and finite element analysis are compared one after another.

The crack propagation on lining is compared for 10 years with previous length of crack in PISD(Precise Inspection for Safety and Diagnosis) depending on the width from 0.2mm to 1mm. Analyzed crack on horseshoe single tunnel is increasing in proportion to square time and linear increment. In this proposal, the extent of crack propagation can be estimated during the elapsed time. The tendency of crack can also be used in evaluating the life cycle of tunnel.

Human embryonic stem cells (hESCs) have been routinely cultured on mouse embryonic fibroblast feeder layers with a medium containing animal materials. For clinical application of hESCs, animal-derived products from the animal feeder cells, animal substrates such as gelatin or Matrigel and animal serum are strictly to be eliminated in the culture system. In this study, we performed that SNUhES32 and H1 were cultured on human amniotic fluid cells (hAFCs) with KOSR XenoFree and a humanized substrate. All of hESCs were relatively well propagated on hAFCs feeders with xeno-free conditions and they expressed pluripotent stem cell markers, alkaline phosphatase, SSEA-4, TRA1-60, TRA1-81, Oct-4, and Nanog like hESCs cultured on STO or human foreskin fibroblast feeders. In addition, we observed the expression of nonhuman N-glycolylneuraminic acid (Neu5GC) molecules by flow cytometry, which was xenotransplantation components of contamination in hESCs cultured on animal feeder conditions, was not detected in this xeno-free condition. In conclusion, SNUhES32 and H1 could be maintained on hAFCs for humanized culture conditions, therefore, we suggested that new xenofree conditions for clinical grade hESCs culture will be useful data in future clinical studies.