• 한국잠사곤충학회지
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• 제47권2호
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• pp.62-67
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• 2005

장려뽕 16 품종에 대한 뽕잎과 오디의 항산화능을 시기별로 채취하여 비교분석 하였다. 항산화능 측정장치(munilum L-100, ABCD GmbH) 및 ARAW-KIT(antiradical ability of water-soluble substance)를 사용하였으며, ascorbic acid를 표준물질로 사용하여 calibration curve를 작성하였다. 시료의 항산화능과 분석에 소요되는 전처리 시간을 고려하여 80% MeOH, 30 sec. vortex mixing 방법을 기준 전처리 방법으로 하였다. 16품종 전체의 뽕잎에 대한 항산화능을 분석한 결과 5개엽기의 어린 뽕잎의 항산화능은 3303.4 nmol로 높았으며, 오디가 착색되기 직전 3708.0 nmol으로 최대 값을 나타낸 후 시기가 경과함에 따라 점차 감소 및 하벌 후 점차 증가 하다가 뽕잎이 경화되기 직전 춘기 어린 잎 정도의 항산화능을 유지하는 것으로 나타났다. 항산화능이 높은 뽕잎을 이용하기 위해서는 5월 하순에 채취하는 것이 수율도 높아 경제성이 있을 것으로 판단되며, 생과 또는 가공식품의 원료로 사용하기 위해 오디를 수확한 후 남은 뽕잎의 이용도 충분히 가능하므로 이를 활용하기 위해서는 하벌 전에 뽕잎의 수확 작업이 이루어지도록 해야 할 것이다. 뽕잎 수확 후 저장하는 방법보다 시기에 따른 뽕잎 자체의 성숙 정도가 뽕잎의 항산화능을 결정하는 것으로 판단된다.

• 한국잠사곤충학회지
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• 제47권2호
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• pp.93-98
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• 2005

야생 뽕나무의 자원화 및 이용기술을 개발하기 위해 강원도 원주, 인제, 양양 3개 지역에서 성숙 단계별로 채취한 야생 뽕나무를 대상으로 뽕잎과 오디의 항산화능을 비교분석 하였다. 항산화능 측정장치(munilum L-100, ABCD GmbH) 및 ARAW-KIT(anti-radical ability of water-soluble substance)를 사용하였으며, ascorbic acid를 표준물질로 사용하여 calibration curve를 작성하였다. 각각의 지역에서 채취한 야생뽕의 형태학적 특성을 조사한 결과, 원주 지역 채집 개체는 백상형(Morus alba L.), 인제 지역 채집 개체는 산상형(Morus bombycis Koidz) 및 양양 지역 채집 개체는 노상형(Morus Lhou (Ser.) Koidz)의 뽕나무로 분류되었다. 강원도 원주, 인제 및 양양 지역에서 자생하고 있는 야생 뽕나무의 뽕잎에 대한 전체적인 항산화능을 분석한 결과 춘기 5개엽기의 어린 뽕잎의 항산화능이 가장 높았으며, 시기가 경과함에 따라 뽕잎의 항산화능은 점차 감소하는 경향이었다. 그러나 개체마다 각각의 특성을 나타냈다. 오디가 결실된 야생 뽕나무 중 오디의 수량성 및 크기 등 착과상태를 고려하여 이용가치가 있을 것으로 예상되는 개체는 No 7, 8, 10이었다. 산상형의 특징을 갖는 No. 7 개체 뽕나무는 뽕잎의 항산화능이 높을 뿐 만 아니라 뽕나무의 생육 상태 및 오디의 결실 상태도 양호했으므로 기능성 및 오디생산용 육종 유전자원으로 이용할 가치가 있는 것으로 판단되었으며, No. 8 및 No. 10 개체 뽕나무는 오디 생산을 위한 유전자원으로 이용할 수 있을 것으로 보인다.

• 한국농공학회지
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• 제18권2호
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• pp.4116-4120
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• 1976

With the use of many rivers increased nearly to the capacity, the need for information concerning daily quantities of water and the total annual or seasonal runoff has became increased. A systematic record of the flow of a river is commonly made in terms of the mean daily discharge Since. a single observation of stage is converted into discharge by means of rating curve, it is essential that the stage discharge relations shall be accurately established. All rating curves have the looping effect due chiefly to channel storage and variation in surface slope. Loop rating curves are most characteristic on streams with somewhat flatter gradients and more constricted channels. The great majority of gauge readings are taken by unskilled observers once a day without any indication of whether the stage is rising or falling. Therefore, normal rating curves shall show one discharge for one gauge height, regardless of falling or rising stage. The above reasons call for the correction of the discharge measurements taken on either side of flood waves to the theoretical steady-state condition. The correction of the discharge measurement is to consider channel storage and variation in surface slope. (1) Channel storage As the surface elevation of a river rises, water is temporarily stored in the river channel. There fore, the actual discharge at the control section can be attained by substracting the rate of change of storage from the measured discharge. (2) Variation in surface slope From the Manning equation, the steady state discharge Q in a channel of given roughness and cross-section, is given as {{{{Q PROPTO SQRT { 1} }}}} When the slope is not equal, the actual discharge will be {{{{ { Q}_{r CDOT f } PROPTO SQRT { 1 +- TRIANGLE I} CDOT TRIANGLE I }}}} may be expressed in the form of {{{{ TRIANGLE I= { dh/dt} over {c } }}}} and the celerity is approximately equal to 1.3 times the mean watrr velocity. Therefore, The steady-state discharge can be estimated from the following equation. {{{{Q= { { Q}_{r CDOT f } } over { SQRT { (1 +- { A CDOT dh/dt} over {1.3 { Q}_{r CDOT f }I } )} } }}}} If a sufficient number of observations are available, an alternative procedure can be applied. A rating curve may be drawn as a median line through the uncorrected values. The values of {{{{ { 1} over {cI } }}}} can be yielded from the measured quantities of Qr$.$f and dh/dt by use of Eq. (7) and (8). From the 1/cI v. stage relationship, new vlues of 1/cI are obtained and inserted in Eq. (7) and (8) to yield the steady-state discharge Q. The new values of Q are then plotted against stage as the corrected steadystate curve.

• 산업기술연구
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• 제3권
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• pp.69-74
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• 1983

For the determination of a reservoir capacity Rippl's mass-curve method has long been used with the past river flow data assuming the same flow records will be repeated in the future. This study aims to find out a better method for determining the reservoir capacity by employing the analytical theory based on the stochastic process. For the present study the synthetic generation methods of Thomas-Fiering type was used to synthetically generate 50 years of monthly river inflows to three single-purpose reservoirs and three multi-purpose reservoirs. The generated sequences of monthly flows were analyzed based on the range concept. With the optimum operation rule of the reservoirs as the one which maximizes the water-use downstream the waterrelease from the reservoir was determined and with due consideration to the mean inflows and the range of monthly flows the required reservoirs capacity was stochastically determined. It was possible to repersent the so-determined reservoir capacity in terms of the mean monthly inflows and the number of subseries in the determination of ranges. It is suggested that the result obtained in this study would be applied to approximately estimate, in the stage of preliminary design, the required capacity of a reservoir in question with the limited information such as the mean monthly inflow and the period of reservoir operation.

• 한국환경과학회지
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• 제20권5호
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• pp.667-672
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• 2011

The purpose of this work is to present the experiment results by a dynamic adsorption of water vapor on pelletized zeolites (ADZ300, ADZ400, and ADZ500) in fixed bed. The breakthrough curves of water vapor with several different concentrations and temperature in the range of 25~45 $^{\circ}C$ on zeolite bed were investigated. In the same conditions, the breakthrough time on ADZ400 and ADZ500 were little longer than ADZ300, and the equilibrium adsorption capacity on ADZ500 was highest. The higher the concentration of water vapor was, the faster the breakthrough time was, and the slope of breakthrough curves showed a tendency to increase. The faster the flow rate of water vapor was, the faster the breakthrough time was relatively, but variations between flow rate and breakthrough time did not have a proportional relationship. The breakthrough curve maintained constant gradient in spite of variation of flow rate in the same concentration. The temperature rise in zeolite bed by adsorption heat was occurred in the early stage of adsorption. After water molecule layers were formed on the surface of zeolite, the temperature was slowly cooled by water vapors continuously flowed in as constant temperature. The greater the concentration of water vapor and adsorption temperature were, the temperature difference in zeolite bed was increased.

• 물과 미래
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• 제19권2호
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• pp.149-156
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• 1986

저수용량을 결정하기 위한 Rippl의 누가곡선법은 과거의 유량자료가 미래에 동일한 기록으로 반복되리라는 가정하에 오랫동안 사용되어 왔다. 본 연구의 목적은 추계학적 이론에 의한 저수용량을 결정하는 더 좋은 방법을 찾아내는데 있다. 그러므로 본 논문에서는 3개의 다목적 댐과 3개의 단일목적댐에 대한 하천의 월 유량을 Tomas-Fiering 법으로 모의발생하였으며 모의발생된 월 유량은 Range 개념으로 해석하였다. 또한 물의 이용을 최대화하는 저수지의 최적운영 법칙을 이용함으로서 저수지로 부터의 유출량을 결정하고 월 유량의 Range와 평균 유입량을 적절하게 고려함으로서 필요한 저수용량은 추계학적으로 결정하였다. 그러므로 본 연구에서 얻어진 결과는 기본설계 단계에서 제한된 자료, 즉 저수지의 운영기간과 월 평균유량을 가지고 필요한 저수지의 용량을 근사적으로 구할 수 있다.

• Water Engineering Research
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• 제1권1호
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• pp.63-74
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• 2000

This paper presents a two- phase search scheme for optimal pipe expansion of expansion of existing water distribution systems. In pipe network problems, link flows affect the total cost of the system because the link flows are not uniquely determined for various pipe diameters. The two-phase search scheme based on stochastic optimization scheme is suggested to determine the optimal link flows which make the optimal design of existing pipe network. A sample pipe network is employed to test the proposed method. Once the best tree network is obtained, the link flows are perturbed to find a near global optimum over the whole feasible region. It should be noted that in the perturbation stage the loop flows obtained form the sample existing network are employed as the initial loop flows of the proposed method. It has been also found that the relationship of cost-hydraulic gradient for pipe expansion of existing network affects the total cost of the sample network. The results show that the proposed method can yield a lower cost design than the conventional design method and that the proposed method can be efficiently used to design the pipe expansion of existing water distribution systems.

• 한국농공학회지
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• 제35권1호
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• pp.50-58
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• 1993

The sedimentation patterns at a reservoir, important to the reservoir capacity curve were simulated using a depth averaged, two-dimensional sediment transport model, that is capable of depicting velocity distributions and sediment transportation. The Banweol reservoir, whose stage capacity relationships have been surveyed before and after the construction, was selected and the daily inflow rates and stages were simulated using a reservoir operation model(DI-ROM). The applicability of the transport model was tested from the comparisons of simulated sedimentation patterns to the surveyed results. The simulated inflow rates and water level fluctuations at the reservoir during twenty-one years from 1966 to 1986, showed that water levels exceeding 80 percent of the total capacity occurred for 70 percent of the periods and inflow rates less than 5000rn$^3$/day sustained for 54 percent of the spans. Dorminant flow directions were simulated from two streamflow inlets to the dam site. And simulated sediment concentrations were higher near the inlets and lower at the inside of the reservoir. Sediment was deposited heavily near the inlets, and portions of sediments were distributed along the flow paths within the reservoir. The comparisons between the simulation results and the surveyed depositions were partially matched. However, it was not possible to compare two results at the upper parts of the reservoir where dredging was carried out few times for the purpose of reservoir maintenance. This study demonstrates that sedimentation patterns within the reservoir are closely related to incoming sediment and flow rates, water level fluctuations, and flow circulation within the reservoir.

• International Journal of Fluid Machinery and Systems
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• 제4권4호
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• pp.367-374
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• 2011

Water hammer pumps can effectively use the water hammer phenomenon in long-distance pipeline networks that include pumps and allow fluid transport without drive sources, such as electric motors. The results of experiments that examined the effect of the geometric form of water hammer pumps by considering their major dimensions have been reported. In addition, a paper has also been published analyzing the water hammer phenomenon numerically by using the characteristic curve method for comparison with experimental results. However, these conventional studies have not fully evaluated the pump performance in terms of pump head and flow rate, common measures indicating the performance of pumps. Therefore, as a first stage for the understanding of water hammer pump performance in comparison with the characteristics of typical turbo pumps, the previous paper experimentally examined how the hydrodynamic characteristics were affected by the inner diameter ratio of the drive and lifting pipes, the form of the air chamber, and the angle of the drive pipe. To understand the behavior of the components attached to the valve chamber and the air chamber that affects the performance of water hammer pumps, the previous study also determined the relationship between the water hammer pump performance and temporal changes in valve chamber and air chamber pressures according to the air chamber capacity. For the geometry of components attached to the drain valve, which is another major component of water hammer pumps, this study experimentally examines how the water hammer pump performance is affected by the length of the spring and the angle of the drain pipe.

• 대한토목학회논문집
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• 제35권5호
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• pp.1039-1049
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• 2015

대규모 다목적댐 지점의 유입량 산정은 수위-저수용량곡선에 댐 축에서 측정된 수위를 적용하여 시간당 저수량변화를 계산한 후 방류량을 감안하여 산정하고 있으나, 이 방법은 태풍 등 대규모 홍수 시에는 급격한 유입량 증가로 인한 배수위 및 강한 바람 등의 영향으로 저수지내의 수위가 균일하지 않아 유입량 산정 시 오차 원인이 되고 있다. 이 외에 기존 수위-저수용량 곡선 방법에 의한 유입량 계산 시 문제점인 댐건설 이후 유입 퇴사로 인한 저수용량의 변화, 댐 지점에서의 수위관측의 불균일성 등 다양한 불확실성이 존재하므로 이에 대한 오차 규명이 반드시 필요하다. 본 연구에서는 저수지 유입량 분석시 분포형 강우유출모형을 이용한 UBC-3P 기법을 적용하여 모형의 모의능력을 평가하였다. 최종적으로 기존 유역내 유입량 관측치와 비교한 결과 Peak유량과 Total유량에서 결정계수가 0.82~0.99 사이값을 나타내므로 댐 지점에서의 모형의 적합성을 확인하였다.