본 논문은 1991년 4월부터 2013년 9월까지의 중국의 상해, 심천 및 홍콩주식시장의 주간 지수자료를 이용하여 중국대륙의 두 시장과 홍콩 시장간 수익률 상호연관성의 정도를 분석하였다. 특히 1997년 7월 1일 에 있었던 홍콩의 중국반환 이전과 이후를 구분하여 비교하였는데, 상 관분석, 그랜저인과분석 및 GARCH(1,1)모형을 이용한 분석결과는 상해 와 심천주식시장은 모든 기간에 걸쳐 상호연관성이 강하게 나타났으며, 홍콩주식시장과 중국본토의 주식시장 간에는 홍콩반환 이전에는 상호연 관성이 없는 움직임을 보였으나 홍콩반환 이후에는 상해주식시장과 심 천주식시장이 홍콩시장에 상당한 영향을 끼쳤으며, 홍콩시장 또한 상해 주식시장과 심천주식시장에 영향을 준 것으로 나타났다. 한편 상해 및 심천주식시장은 홍콩시장에 비해 시장의 충격에 아주 민감하게 반응을 보였으며, 충격 후 회복도 빠른 것으로 나타났다. 결론적으로 홍콩의 반 환이전부터 상당한 상호연관성을 보인 중국본토의 두 주식시장은 반환 이후에는 홍콩주식시장과 동조화현상을 보여주고 있음을 알 수 있다.
A steady-state controllable M/G/1 queueing model operating under the (TN) policy is considered where the (TN) policy is defined as the next busy period will be initiated either after T time units elapsed from the end of the previous busy period if at least one customer arrives at the system during that time period, or the time instant when Nth customer arrives at the system after T time units elapsed without customers’ arrivals during that time period. After deriving the necessary system characteristics such as the expected number of customers in the system, the expected length of busy period and so on, the total expected cost function per unit time in the system operation is constructed to determine the optimal operating policy. To do so, the cost elements associated with such system characteristics including the customers’ waiting cost in the system and the server’s removal and activating cost are defined. Then, the optimal values of the decision variables included in the operating policies are determined by minimizing the total expected cost function per unit time to operate the system under consideration.
Using the known result of the expected busy period for a controllable M/G/1 queueing model operating under the triadic Max (N, T, D) policy, its upper and lower bounds are derived to approximate its corresponding actual value. Both bounds are represented
Us ing the known result of the expected bllsy period for the triadic Min (N, T, 0) operating po licy applied to a controllable M/GI1 queueing model, its upper and lower bounds are derived to approximate its corresponding ac tual value. 80th bounds are rep
Using the results of the expected busy periods for the dyadic Min(N, D) and Max(N, D) operating policies in a controllable M/G/1 queueing model, an important relation between them is derived. The derived relation represents the complementary property betw
The expected busy period for the controllable M/G/1 queueing model operating under the triadic Max (N, T, D) policy is derived by using a new concept so called “the pseudo probability density function.” In order to justify the proposed approaches for the
The expected busy period for the controllable M/G/1 queueing model operating under the triadic policy is derived by using the pseudo probability density function which is totally different from the actual probability density function. In order to justif
A model experiment on the pair midwater trawl net applicable to 800 PS class Korean pair bottom trawlers was carried out in the special-prepared experimental thank. the tank was prepared as a reverse trapezoid shape in its vertical section by digging out flat soil. The dimension of the tank showed the 9.6 W×43.0 L(m) of the upper fringe and the 4.8 W×38.0 L(m) of the bottom with 3.0m in depth. The depth of water was maintained 2.7m during experiment. The model net was prepared based on the Tauti's similarity law of fishing gear in 1/30 scale considering the dimension of the experimental tank. Mouth performance of the model net during towing were determined by the photographs taken in front of the net mouth with the combinations of towing velocity, warp length and distance between paired boats. The results obtained can be summarized as follows: 1. Vertical opening of the model nets A and B was varied in the range of 0.18~0.88 m and 0.21~0.78 m (which can be converted into 5.4~26.4m and 6.3~23.4 m in the full-scale net) respectively, and was varied predominantly by towing speed. Vertical opening (H which is appendixed m for the model net. f for the full-scale net. A and B for the types of the model net) can be expressed as the function of towing velocity〈TEA〉Vtas in the model net 〈TEA〉〈/TEX〉Vt〈/TEX〉 : m/ sec)〈TEA〉HmA=1.67〈TEA〉〈/TEX〉e-1.65Vt〈/TEX〉 〈TEA〉HmB=1.15〈TEA〉〈/TEX〉e-1.13Vt〈/TEX〉, in the full-scale net (〈TEA〉Vt : k't) 〈TEA〉〈/TEX〉HfA〈/TEX〉=50.27〈TEA〉e-0.37Vt 〈TEA〉〈/TEX〉HfB〈/TEX〉=34.46〈TEA〉e-0.26Vt. 2. Horizontal opening of the model nets An and b was varied in the range of 1.03~1.54m and 1.04~1.55 m (which can be converted into 30.9~46.2 m and 31.2~46.5m in the full-scale net) respectively, and was varied predominantly by distance between paired boats. Horizontal opening (W, appendixes are as same as the former) an be expressed as the function of distance between paired boats 〈TEA〉〈/TEX〉Db〈/TEX〉as in the model net 〈TEA〉WmA=0.69+0.09〈TEA〉〈/TEX〉Db〈/TEX〉 〈TEA〉WmB=0.73+0.09〈TEA〉〈/TEX〉Db〈/TEX〉, in the full-scale net 〈TEA〉WfA=20.81+0.09〈TEA〉〈/TEX〉Db〈/TEX〉 〈TEA〉WfB=22.11+0.09〈TEA〉〈/TEX〉Db〈/TEX〉 3. Net opening area of the model net A and B was varied in the range of 0.28~1.04 〈TEA〉m2 and 0.33~0.94〈TEA〉〈/TEX〉m2〈/TEX〉(which can be converted into 252~936〈TEA〉m2 and 297~846〈TEA〉〈/TEX〉m2〈/TEX〉 in the full-scale net) respectively, and was varied predominantly by towing velocity. Net opening area (〈TEA〉S, appendixes are as same as the former) van be expressed as the function of towing velocity〈TEA〉〈/TEX〉Vt〈/TEX〉 as in the model net 〈TEA〉vt : m/sec) 〈TEA〉〈/TEX〉SMa〈/TEX〉=2.01〈TEA〉e-1.54VT 〈TEA〉〈/TEX〉SmA〈/TEX〉=1.40〈TEA〉e-1.65Vt, in the full-scale net (〈TEA〉Vt : k't) 〈TEA〉〈/TEX〉SfA〈/TEX〉=1.807〈TEA〉〈/TEX〉e-0.35Vt〈/TEX〉 〈TEA〉SfA=1.265〈TEA〉〈/TEX〉e-0.24Vt〈/TEX〉. 4. Filtering volume of the model nets A and B was varied in the range of 0.32~0.55 〈TEA〉m3 and 0.37~0.55〈TEA〉〈/TEX〉m3〈/TEX〉(which can be converted into 8.640~14.850 〈TEA〉m3 and 9.990~14.850〈TEA〉〈/TEX〉m3〈/TEX〉in the full~scale net) respectively, and was predominantly varied by towing speed. filteri..
부산시 선적의 근해안강망 어선에서 사용하고 있는 어구의 1/10, 1/20 모형을 제작하여 흐름이 비교적 빠른 연안에서 전개상태를 측정 및 관찰한 결과는 다음과 같다. 1. 전개장치의 전개높이, 전개간극 등은 네갈랫줄의 상대적 길이에 따라 상당히 다르며, 보편적으로 사용하고 있는 바와 같이 네갈랫줄의 길이를 길게 하고, 맨 위쪽 줄의 길이를 그 보다는 짧게한 방식이 효과적이며, 가장 효과적인 것은 갈랫줄의 길이를 아래로부터 차례로 맨 아랫것 보다 5%, 9%, 4%씩 길게 한 것이 전개 높이, 전개간극, 전개면적 등의 모든 면에서 가장 효과적이었다. 2. 흐름이 빨라지면 등판과 밑판의 평면형상은 뜸줄과 발줄이 아주 심하게 만곡되고, 그물 길이의 2/5 정도까지는 망지가 뒤로 많이 쏠려서 망구에 있어서의 물의 여과를 혼란시켜 어군의 입망을 방해할 것 같고, 또 밑판이 해저의 장애물에 걸렸을 때는 파망의 우려가 크다. 3. 유체저항을 실물어구의 것으로 환산하면 R=29.2×103 v1.65 이라고 표현되고, 이것을 그물의 설계상 구성요소를 고려한 식으로 바꾸면 R=5.9×d/l×abv1.65 이라고 표현된다.
In order to investigate the performance for the mackerel purse seine of one boat purse seiner using in the sea area of Cheju Island, a model net is made of the scale of 1/400 of its full scale, and model test on the shape of net and the tension of purse line is carried out in the stagnant water channel of the circulating water tank. Designing and testing for the model net are based on the Tauti's law. The obtained results are as follows; 1. The sinking rate of net is maximized the value of 6.40 m/min from 5 to 10 minutes after shooting net, and the mean value is 6.13 m/min. 2. The enclosed area formed with the float line after pursing operation is 76-84% of the area which is formed immediately after the shooting operation. At that time, purse seine is pulled inward the circle of surrounding net about 26.5% of the diameter. 3. In operating, when longitudinal section area of the central part of the net is maximized, the split area of both the wing-ends is 31-32% of the former. 4. When the time for the completing of pursing is 20 minutes, the maximum tension of the purse line is about 10.2 tons.
국내의 하천에는 많은 수의 보가 설치되어 있으며, 이러한 특성은 국외에서는 흔하지 않은 편이다. 흐름이 보와 같은 구조물을 통과하는 경우에는 불연속 흐름이 발생하게 되며, 수치모의 측면에서는 흐름항과 생성항의 균형 등의 문제로 수치적 안정성에 많은 영향을 준다. 이러한 문제점을 해결하기 위해서 경험식이나 해석기법의 단순화 등에 의존해 왔으며, 최근에 들어서는 보다 정확한 수치해석기법을 이용하려는 연구가 꾸준히 수행 되고 있다. K-River는 국내의 하천 특성을 반영하고, 불연속 흐름을 보다 정확히 계산하기 위한 목적으로 개발되었다. K-River의 검증을 위하여 1) 하상융기가 존재하는 개수로 수치실험 모의, 2) 도수현상 실내실험 모의, 3) 실제 하천의 수문 사상 모의를 수행하였다. 모든 모의에서 해석해 및 관측치와 유사한 결과를 모의하여 K-River의 적용성을 검증하였다.