The proposed evaporation disk model is improved to figure out two flow system ~n the observed bipolar molecular outflow and stellar optical jet. Using the improved model, we can interpret the dymanical interactions of the two flows as well as obtain the physical parameter distributions along the flows Numerical & analytical adiabatic hydrodynamic calculations of the stellar jet inside show that the jet Mach number increases with an inversely proportional to the jet radius and M₁∼35, V₁∼150㎞/sec, Z₁∼0.1 pc, R₁∼0.05pc, T₁∼10³K, ρ₁-4.3×10^(-3)g/㎤(n₁∼25/㎤) at the end of the flow. By the way, in the case of the molecular flow. which is developed from the evaporated disk wind, the same calculations show that the flow Mach number increases with an inversely proportional to the mass flux distribution and M_d∼15, V₁∼15㎞/sec, Z_d∼1pc, R_d∼025pc, T_d∼10²K, ρ_d∼4.0×10^(-3)g/㎤(n_d∼25/㎤) at the flow end Most of the calculated physical parameters in the two flows consistent with the observational ones very well. The theoretically calculated flows develope the supersonic flows to make the shocked regions at the ends of flows. These regions are gravitationally unstable to produced the fragmentations whose masses are∼2 M- in the stellar let case and 0.3 M_⊙ in the bipolar flow case. This mass distribution supports that both the origins of Herbig-Haro objects and the birth of low mass stars are attributed to the instabilities of the shocked regions in the stellar jets and the bipolar molecular flows respectively.

In order to explain the apparent alternation in VLA jet structures, we appeal to evaporation from an outer disk to switch the direction of the central energetic flow by a process of 'optical depth modulated' choking, That is as the radiation from a central engine heats the surface of an extended disk surrounding the engine, the disk surface will evaporate thermal gas, expanding the disk atmosphere and creating a disk wind. We argue that its dynamic pressure plays a very important role in confining the central energetic flow. If the disk has initially an asymmetric density distribution in the upper and lower atmospheres (i. e., asymmetric distribution of optical depth), then this can initiate the alternating jets(flip-flop jets), A flip-flop time scale is calculated from the rate of optical depth variation in the disk atmosphere(e.g., the optically thin atmosphere becomes optically thick due to the mass influx from the central engine), This gives a time scale of 3×10^7 yrs, which value, however, is strongly dependent on the size of the jet cavity where in the density(optical depth) is varied. We compare the theoretically derived flip-flop time scale to those estimated observationally for the standard straight, as well as the rotationally and mirror symmetric radio sources. The prediction is found to be reasonably consistent with the observationally derived time scales of the standard straight radio sources, however it is likely to be longer than those in the rotationally and mirror symmetric radio sources.

An evaporation disk model is proposed_to figure out shapes of molecular disks with density distributions of ρ_d∝r^(-n)(n$gt;1.8) using the energy and pressure equilibrium conditions as well as to explain the collimation mechanism of optical and radio jets with an openning angle of about 10 inside bipolar molecular outflows. Numerical hydrodynamic calculation of the jet inside shows that the jet velocity increases with a dependence on z^(1-5) and the Mach number of the jet converges to √3 . Mechanical energy of the jet heats the jet material, increasing the jet temperature with a distance. Calculated Ha flux in shock condition and radio continuum intensity at 5GHz are surely comparable to the observed ones. These results strongly support the evaporation disk model in collimating jet.

Recently, a heavy rainfall with high spatial variation occurred frequently in the Korean Peninsula. The meteorological event that occurred in Busan on 3 May 2016 is characterized by heavy rain in a limited area. In order to clarify the reason of large spatial variation associated with mountain height and location of low level jet, several numerical experiments were carried out using the dynamic meteorological Weather Research and Forecasting (WRF) model. In this case study, the raised topography of Mount Geumjeong increased a barrier effect and air uplifting due to topographic forcing on the windward side. As a result, wind speed reduced and precipitation increased. In contrast, on the downwind side, the wind speed was slightly faster and since the total amount of water vapor is limited, the precipitation on the downwind side reduced. Numerical experiments on shifting the location of the lower jet demonstrated that if the lower jet is close to the mountain, its core becomes higher due to the effect of friction. Additionally, the water vapor convergence around the mountain increased and eventually the precipitation also increased in the area near the mountain. Hence, the location information of the lower jet is an important factor for accurately predicting precipitation.

본 연구에서는 정체수역으로 방류되는 수평병합부력제트에 대한 실험을 수행하여, 평민제트의 고유한 특징으로만 알려져 왔던 진동운동에 대해 구명하고자 하였다. 연구결과, 진동운동은 병합부력제트에서도 확인되었으며, 특히 병합천이역 시점에서부터 관찰되었다. 흐름의 국부적인 특성치와 진동운동을 야기하는 와의 통과빈도와의 관계를 나타내는 Strouhal수는 병합천이역에서 변화하여 병합이 완전히 이루어진 후에는 일정한 값으로 수렴하는 것으로 관측되었다. 평면제트에 대