The organic complexing agents such as ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and isosaccharinic acid (ISA) can enhance the radionuclides’ solubility and have the potential to induce the acceleration of radionuclides’ mobility to a far-field from the radioactive waste repository. Hence, it is essential to evaluate the effect of organic complexing agents on radionuclide solubility through experimental analysis under similar conditions to those at the radioactive waste disposal site. In this study, five radionuclides (cesium, cobalt, strontium, iodine, and uranium) and three organic complexing agents (EDTA, NTA, and ISA) were selected as model substances. To simulate environmental conditions, the groundwater was collected near the repository and applied for solubility experiments. The solubility experiments were carried out under various ranges of pHs (7, 9, 11, and 13), temperatures (10°C, 20°C, and 40°C), and concentrations of organic complexing agents (0, 10-5, 10-4, 10-3, and 10-2 M). Experimental results showed that the presence of organic complexing agents significantly increased the solubility of the radionuclides. Cobalt and strontium had high solubility enhancement factors, even at low concentrations of organic complexing agents. We also developed a support vector machine (SVM) model using some of the experimental data and validated it using the rest of the solubility data. The root mean square error (RMSE) in the training and validation sets was 0.012 and 0.016, respectively. The SVM model allowed us to estimate the solubility value under untested conditions (e.g., pH 12, temperature 30°C, ISA 5×10-4 M). Therefore, our experimental solubility data and the SVM model can be used to predict radionuclide solubility and solubility enhancement by organic complexing agents under various conditions.

When considering military operations that require rapid response time, forward supply operation of various type of ammunition is essential. Also, t is necessary to supply ammunition in a timely manner before an ammunition shortage situation occurs. In this study, we propose a mathematical model for allocation of ammunition to ammunition storehouse at the Ammunition Supply Post (ASP). The model has several objectives. First, it ensures that the frequent used ammunition is stored in a distributed manner at a high workability ammunition storehouses. Second, infrequent used ammunition is required to be stored intensively at a single storehouse as much as possible. Third, capacity of the storehouse and compatible storage restriction required to be obeyed. Lastly, criticality of ammunition should be considered to ensure safety distance. We propose an algorithm to find the pareto-based optimal solution using the mathematical model in a reasonable computation time. The computational results show that the suggested model and algorithm can solve the real operational scale of the allocation problem.

지난 50여 년간의 연구를 통해서 와류진동의 발생메커니즘과 폭 넓은 이해를 위한 수학적 모델이 제시된바 있으나 대부분 실 험적 고찰과 경험적 모델에 기반한 현상학적인 접근이 주로 이루어졌다. 와류진동과 그에 수반된 독특한 현상, 유체의 흐름과 구조물의 상호작용에 내포되어 있는 복합성과 난해성은 지금도 많은 연구자들의 관심을 불러일으키고 있으며, 와류진동에 대한 원초적인 발생원인 규명에 대한 새로운 도전이 지속적으로 제기되고 있다. 본 연구에서는 하중식별법에 의해 와류하중을 직접 추출하고 스펙트럼 형상분석을 통하여 와류하중을 구성하는 요소하중을 도출하는 과정을 보였다. 와류진동을 구성하는 요소하중은 구조물의 속도가 공력 감쇠에 의하여 피드백되는 하중, 와의 발생에 의한 하중(스트로할 성분에 의한 순수와류하중), 풍직각방향 버펫팅 하중으로 구분됨을 알 수 있었다. 각 요소 하중이 구조물 응답에 미치는 영향을 분석하여 본 연구에서 제시된 와류하중 모델도출법의 정합성을 보임으로서, 모델 구축방법의 타당성을 제시하였다. 이들 요소하중에 대한 정량적인 수학적 모델의 정립을 위해서는 피드백하중의 공력감쇠예측, 순수와류하중 스펙트럼의 정량적인 분포와 그 크기 예측, 버펫팅 하중의 스펙트럼 성상 예측이 이루어져야 한다. 이를 위해 풍동실험, 실계측과 같은 현상학적인 접근방법과 유체 흐름의 정형화된 수학적 모델인 나비에-스톡스 방정식과 연계된 CFD 해석을 병행하여 와류하중을 구성하는 요소하중들에 대한 정량화된 수학적 모델의 정립이 요구된다.

In the satellite operation phase, a ground station should continuously monitor the status of the satellite and sends out a tasking order, and a satellite should transmit data acquired in the space to the Earth. Therefore, the communication between the satellites and the ground stations is essential. However, a satellite and a ground station located in a specific region on Earth can be connected for a limited time because the satellite is continuously orbiting the Earth, and the communication between satellites and ground stations is only possible on a one-to-one basis. That is, one satellite can not communicate with plural ground stations, and one ground station can communicate with plural satellites concurrently. For such reasons, the efficiency of the communication schedule directly affects the utilization of the satellites. Thus, in this research, considering aforementioned unique situations of spacial communication, the mixed integer programming (MIP) model for the optimal communication planning between multiple satellites and multiple ground stations (MS-MG) is proposed. Furthermore, some numerical experiments are performed to verify and validate the mathematical model. The practical example for them is constructed based on the information of existing satellites and ground stations. The communicable time slots between them were obtained by STK (System Tool Kit), which is a well known professional software for space flight simulation. In the MIP model for the MS-MG problems, the objective function is also considered the minimization of communication cost, and ILOG CPLEX software searches the optimal schedule. Furthermore, it is confirmed that this study can be applied to the location selection of the ground stations.

In this paper, a mathematical model of regionalization based on graph theory to investigate the patterns induced by movements of livestock vehicles in cities under outbreaks of highly pathogenic avian influenza (HPAI) is proposed. We then compare the results of simulation from the regionalization model to actual HPAI outbreaks in 2016/2017 to evaluate the validity of the model. Specifically, we (1) configured a complex network structure with analytic tools and properties in graph theory to abstract the paths among farms and livestock facilities; (2) employed statistical methods to estimate the possibility of propagation between two clusters; (3) applied the developed method to an actual HPAI outbreak in Korea in 2016 and conducted a simulation to determine if the proposed modeling for regionalization is an effective prediction measure. The clustered regions proposed by the simulation correctly reflected the regional clustering of actual cases, while simultaneously contain the cities exposed to potential damage when separated. Based on these findings, we conclude that our proposed regionalization model is suitable for making policy judgments to establish a preemptive biosecurity system.

With the increased interest in the quality of life of modern people, the implementation of the five-day working week, the increase in traffic convenience, and the economic and social development, domestic and international travel is becoming commonplace. Furthermore, in the past, there were many cases of purchasing packaged goods of specialized travel agencies. However, as the development of the Internet improved the accessibility of information about the travel area, the tourist is changing the trend to plan the trip such as the choice of the destination. Web services have been introduced to recommend travel destinations and travel routes according to these needs of the customers. Therefore, after reviewing some of the most popular web services today, such as Stubby planner (http://www.stubbyplanner.com) and Earthtory (http://www.earthtory.com), they were supposed to be based on traditional Traveling Salesman Problems (TSPs), and the travel routes recommended by them included some practical limitations. That is, they were not considered important issues in the actual journey, such as the use of various transportation, travel expenses, the number of days, and lodging. Moreover, although to recommend travel destinations, there have been various studies such as using IoT (Internet of Things) technology and the analysis of cyberspatial Big Data on the web and SNS (Social Networking Service), there is little research to support travel routes considering the practical constraints. Therefore, this study proposes a new mathematical model for applying to travel route recommendation service, and it is verified by numerical experiments on travel to Jeju Island and trip to Europe including Germany, France and Czech Republic. It also expects to be able to provide more useful information to tourists in their travel plans through linkage with the services for recommending tourist attractions built in the Internet environment.

We present a mathematical model that predicts the variation of illuminance during a solar eclipse, considering continuous effects of limb darkening. We assume that (1) the Sun and the Moon constitute perfect spheres, (2) the Moon crosses the Sun with a constant apparent velocity, and (3) sunspots, prominences, and coronae can be neglected. We compare predictions of this model with actual measurements made by Mollmann & Vollmer (2006) during a total solar eclipse in Turkey, and with predictions of existing models. The new model is shown to describe the actual phenomenon more accurately than existing models.

Predictive mathematical models were developed for predicting the kinetics of growth of Listeria monocytogenes in smoked salmon, which is the popular ready-to-eat foods in the world, as a function of temperature (4, 10, 20 and 30℃). At these storage temperature, the primary growth curve fit well (r² = 0.989~0.996) to a Gompertz equation to obtain specific growth rate (SGR) and lag time (LT). The Polynomial model for natural logarithm transformation of the SGR and LT as a function of temperature was obtained by nonlinear regression (Prism, version 4.0,GraphPad Software). Results indicate L. monocytogenes growth was affected by temperature mainly, and SGR model equation is 365.3-31.94*Temperature+0.6661*Temperature^2 and LT model equation is 0.1162-0.01674*Temperature+0.0009303*Temperature^2. As storage temperature decreased 30℃ to 4℃, SGR decreased and LT increased respectively. Polynomial model was identified as appropriate secondary model for SGR and LT on the basis of most statistical indices such as bias factor (1.01 by SGR, 1.55 by LT) and accuracy factor (1.03 by SGR, 1.58 by LT).

Tsutsugamushi disease, caused by a rickettsial bacteria known as Oriental tsutsugamushi, is one of the most febrile illnesses occurring throughout Korea during fall. O.tsutsugamushi is transmitted by the bite of infected, immature mites of the genus Leptotrombidium. The mites have four-stage life cycles : egg, larva, nymph, and adult. The larva is the only stage that can transmit the disease to humans and other vertebrates, since the other life stages do not feed on the host. During the process of obtaining a blood meal, they may either acquire the infection from the host or transmit the rickettiae to the other rodents or humans. The model can be divided the life cycle of mite into 2 stages : Larva and Adult. And the larva stage can be subdivided according to the phase of activity : questing and feeding. Mites enter either the susceptible questing larvae or infectious questing larvae through birth. When the larva bites an infectious hosts, then the larva moves from the susceptible questing to the infectious feeding class with some probability. On the other hand, hosts also enter the susceptible class through birth. And when an infectious larva bites a susceptible host, then the host enters the infectious class with some probability. In this talk, we introduce our mathematical model for the tsutsugamushi disease, and show the existence and stability condition of the disease-free equilibrium, which is a kind of threshold for the tsutsugamushi disease transmission, and also define the basic reproduction ratio R0. And we discuss about R0 related to all parameters.

A mathematical model for the synergistic interaction of physical and chemical environmental agents was suggested for quantitative prediction of irreversibly damaged cells after combined exposures. The model took into account the synergistic interaction of

원자력시설 해체부지를 재이용하는 과정에서 유발될 수 있는 방사선학적 리스크를 사전에 선별하기 위한 목적으로 단순화된 방사선량 평가모델을 개발하고, 이를 Microsoft 스프레드시트와 내장된 Visual Basic 및 마크로 기능을 활용하여 기능별로 모듈화된 평가도구를 구현하였다. 이와 함께 부지 특성자료가 불충분할 경우 신속한 사전평가를 위해 적용할 수 있는 일련의 입력변수 값 목록을 제안하였다. 동일한 조건에서 이 연구에서 개발된 평가도구를 이용해 유도한 사전 선별준위가 RESRAD Ver.6.2를 이용해 계산된 유도농도지침한계 및 독일 방사선방호령에 규정된 핵종별 부지 재이용 기준농도를 합리적으로 근사할 수 있음을 확인하였다.

크로스도킹이란 창고나 물류센터에 하역된 물품이 저장됨이 없이 도착지별로 재분류되어서 직출하되는 물류 시스템이다. 크로스도킹은 물류비용의 큰 비중을 차지하는 보관비용을 감소시킬 수 있을 뿐만 아니라 고객의 요구에 빠른 대응을 할 수 있다는 장점을 지니고 있다. 크로스도킹이 성공적으로 수행되기 위해서는 창고나 물류센터의 입고에서부터 출고까지의 모든 작업들이 계획적이고 원활하게 수행되어져야만 한다. 본 연구에서는 임시보관 장소를 보유하지 않은 크로스도킹 시스

선박의 항행안전의 문제가 중요시됨에 따라 선박조종시뮬레이터를 이용한 운항훈련, 안전성 검토 등이 필요성이 중요하게 인식되고 있다. 또한 추진성능을 향상시킬 목적으로 다양한 선종이 출현되고 있고, 이에 따라 선박조종시뮬레이터의 개발에 있어서 선박의 데이터베이스는 필수적이라고 할 수 있다. 따라서 선종에 따른 수학모델을 각각 선박조종시뮬레이터에 적용시킴으로써 다양한 조종 시뮬레이션을 가능하게 할 수 있다. 본 논문에서는 우수한 추진성능을 목적으로 한 2축2타선박을 대상으로 조종운동 수학모델을 정식화하였다. 구체적으로 항만내에서의 저속시 조종운동을 구현할 수 있는 수학모델에 대해서 검토하였으며, 선체·프로펠러·타의 상호간섭에 대해서도 고려하였다. 또한, 수치시뮬레이션을 수행함으로써 2축2타선박의 기본적인 조종성능을 확인하였다.

The propriety of the numerical model application was examined on Paldang resevoir and its inflow tributaries located in the center of the Korean peninsula and the long term water quality forecast of the oxygen profile was carried out in this syduy. The input data of the model was the capacity of the reservoir, catchment area, percolation, diffusion rate, vertical mixing rate, dissolution rate from the bottom of the reservoir, outflow of the resevoir, water quality measurement and meteorology data of the drainage basin, and the output result was the annual estimation value of the dissolved oxygen concentration and the biochemical oxygen demand. The modeling method is based on the measured or calculated boundary condition dividing the water area into several blocks from the macorscopic aspect and considering the mass balance in these blocks. As the result of the water quality forecast, it was expected that the water quality in Northern Han River and Paldang reservoir would maintain the recent level, but that the water quality in the Southern Han River and its inflow tributary would worsen below the grade 4 of the life environmental standard from around 2000 owing to the decrease of DO concentration and the increase of BOD concentration.

Most of eco-friendly agrifood processing enterprises in Korean rural area are small and medium-sized business. For this reason, it’s hard for eco-friendly agrifood processing enterprises to neither analyze business performance for efficient business management nor establish their own business plan for rational decision-making. Therefore it’s necessary to design effective mathematical programming model and to make practical application which can support rational management decisionmaking ensuring the stable business activity of eco-friendly agrifood processing enterprises. Accordingly this paper focuses on the designing and its application of multi-objective mathematical programming model using goal programming to support rational decision-making of eco-friendly agrifood processing enterprise. Hansalimanseongmachum Food Inc. which runs soy bean processing business making tofu based on regional-based soybean farms around Anseong City will be the specific case to apply multi-objective mathematical programming model in practice. And it will suggest measures to support rational management decisionmaking of other eco-friendly agrifood processing enterprises.

본 논문은 빛의 조명으로 defense 게임 플레이에 대한 캐릭터 표면모델을 시뮬레이션하는 데 프레넬의 수학적 모델을 제안한다. 여기서 illumination은 게임에서 사용되는 캐릭터표면 모델에 도달하는 빛의 양을 결정하는 프로세스를 나타낸다. 캐릭터 표면의 shader는 일반적으로 빛이 triangle에 반영하는 방법 즉 예측하는 수학적 모델을 사용한다. shading은 일반적으로 색상과 빛의 강도를 결정하기 위해 사용되는 방법인데, viewer에서 본다면 게임 캐릭터의 표면 위에 각 픽셀에 대한 반사결과를 나타낸다. 여기서 제안 모델은 반사와 투과 계수를 계산하여 실제 게임 플레이를 하면서 프레넬 방정식으로 시뮬레이션 결과를 비교하였다.

세계 컨테이너 물동량의 증가와 컨테이너선의 대형화로 인해 선박과 수심이 얕은 항구 및 부두를 연결하는 새로운 개념의 해상 운송 수단이 요구되어 왔다. 본 연구에서는 모바일하버 선형과 함께, Azipod 추진기 및 선수 스러스터(Bow thruster) 등으로 구성된 모바일하버의 조종수학모델을 구축하였다. 그리고 선체 유체력 및 Azipod 추력 등을 평가 적용하여 조종운동 시뮬레이션을 수행하였다. 그 결과, 모바일 하버의 조종운동 시뮬레이션에 의한 선회성능과 조종제어범위를 사전에 예측할 수 있었다. 또한, 모바일하버의 직진 시험 및 선회성능 시험에 있어 양호한 결과를 얻었으며, 접안 시 Azipod 추진기와 선수 스러스터를 이용한 최적의 조종운동 시뮬레이션을 확립하였다.