With the increasing prevalence of smartphones, marketers have a keen interest in the mobile channel hoping to enhance the effectiveness of marketing activities and improve sales performance. Prior research on mobile marketing examines for example, coupon redemption, time sensitivity, and message optimization, and find that marketing activities and the corresponding performance should be understood based on contexts in which such actions are employed. Following this stream of research, we focus on the context in which consumers interact with mobile phones, and evaluate the role of real-time mobile coupons in driving e-commerce interest. To this end, we collaborate with an online retailer selling beauty products as well as a credit card company distributing mobile coupons on behalf of the online retailer. Target customers are selected using prior usage of credit cards such as category preference and spending amount. When SMS texts are being sent to smartphones with transaction confirmation, mobile coupons are attached to such texts in order to induce target consumers to sign up for the online retailer. Thus our data comes from two sources. The credit card company provides transaction information along with demographics and the online retailer track consumers’ behavior in log and purchase data. Our empirical analyses suggest that real-time contexts matter in determining the effectiveness of mobile coupons. To be specific, consumers who have just spent a small amount of money show a greater propensity to redeem the coupons despite small rewards. Also, heavy users of e-commerce tend to be more responsive to the coupons promoting the online retailer whereas those with large spending on beauty products are less likely to sign up. We discuss theoretical contributions of these findings and offer practical insights.

본 연구에서는 낙동강 진우도 해빈에 모래 포집시험구(실험 Site)를 설치하고 자연해빈에서의 비사 계측, 광파측거의를 통해 대표 해빈단면의 변화를 관찰하여 서로 비교분석하였다. 또한 해빈에서 바람에 의해 공급되는 모래(비사)의 해안 법선방향 및 평행한 방향의 모래 공급량을 정량적으로 평가하고자 하였다. 또한 실내에서의 풍동실험장치를 이용하여 해빈상에 초기 성장조건에 해당하는 식생의 이식하여 바람에 의해 이송되는 비사의 포집특성을 관찰하였다.

Models are useful tools for understanding and improving biological control of arthropod pests by means of natural enemies. Thus, models can be applied to simulate various scenarios in order to identify optimal control strategies. Although simulations can never replace real experiments, they can often serve as guidelines for choosing relevant field experiments and thereby save a lot of laborious and costly field work. Whereas the processes underlying population dynamics (e.g. dispersal, functional response, mutual interference) can be studied under laboratory conditions, large-scaled experiments in the field or in greenhouses are unsuited for this purpose. Instead such experiments may provide information about the patterns (e.g. spatial distributions of prey and predators) generated by the underlying processes. A major purpose of modeling is to link the patterns to the processes that generate these patterns. Petri-dish and single plant experiments have clearly demonstrated the capacity of predacious mite Phytoseiulus persimilis to feed effectively on the two-spotted spider mite Tetranychus urticae. This quickly leads to reductions in the abundance of prey, followed by a decline in predator abundance and eventual extinction. However, when larger systems, consisting of many hundred plants, are infested with the two mite species, extinction of one or both species seems less likely at the system level, although it may still occur at the individual plant level. The qualitative difference between small and large systems with respect to persistence and extinction risks is attributed to the fact that mites move among plants, but to prove that dispersal per se plays a role for the overall dynamics is hard to demonstrate experimentally. To circumvent this problem, I developed a stochastic simulation model of a greenhouse system that explicitly incorporates within and between plant dynamics. The model is used for analyzing a series of experiments with biological control of spider mites in multi-plant systems. In these experiments, the number of plants as well as their connectivity and the numbers of introduced mites were varied in order to examine whether these factors affect e.g. the predator-prey ratio or the time to extinction of one or both species. In my presentation I will also demonstrate an interactive version of the model (called DynaMite). It allows the user to interfere in the system during a simulation so as to mimic the options a grower has in order to prevent losses and to maximize his profit. Such options include spraying with acaricides, releasing predators, and replanting in substitute of damaged plants. By choosing different control strategies, the user may gradually improve his skills according to the principle of learning by experience. The model can be freely downloaded from http://www1.bio.ku.dk/ansatte/beskrivelse/?id=43077

In this study, the underground box culvert were selected in nine construction sites and the influencing factors of underground structures on concrete degradation were verified through the field and laboratory experiments.

표류지점 추정 모델의 환경 입력자료를 확보하기 위해 부산항 연근해에서 표류실험을 실시하였다. 실험에는 크기가 다른 4척의 선박(10, 20, 50, 90톤급)이 사용되었다. 그중 50톤급 선박에는 해류, 바람, 위치를 자동적으로 기록하는 계기들을 장착하였고, 나머지 선박들에서는 분산각 추정 연구를 위해 위치자료만 기록하였다. 각 선박들의 위치는 DGPS와 자동위치발신기(APRS)를 사용하여 기록하였다. 실험은 풍속 2~10m/s, 유속 0.5~1.5m/s의 환경에서 행하여졌으며, leeway는 선박 표류속도에서 표층의 유속성분을 제거하여 구하였다. 50톤급 선박의 leeway rate는 풍속의 약 3.6%인 것으로 분석되었으며, leeway 방정식은 UL =0.042W -0.034로 표현되었고 leeway angle은 -30˚~40˚의 범위였다.