Earticle

자사의 제품을 무료로 경험할 기회를 제공하고 추가 기능에 대해 기꺼이 비용을 지불할 만큼 그 이용을 가치 있게 생각하는 소비자들에게 premium 기능 및 제품을 판매함으로써 수익을 창출하는 freemium은 오늘날 IT 기업들이 빠른 시장침투를 위해 사용하는 대표적인 전략이다. 기업들은 유료 premium의 구매를 유도할 시에 대체로 구독이나 단위 서비스당 구매방법을 제시하며, 최초에 무료로 소비자들에게 서비스를 제안하는 단계에서 모든 기능을 다 쓸 수 있는 완전 버전으로 제공한 다음 일정 기간 후에 이를 축소하는 정책을 시행하거나 애초에 제한된 버전을 제공하고 프리미엄 기능에 대해 구매를 유도하는 방법을 쓴다. 기업이 프리미엄 서비스에 대해 구독과 단위 당 구매 옵션을 둘 다 제시하는 전략을 취한다면 최초로 제공할 무료서비스에 대해 완전한 품질과 제한된 품질 사이에서 어떠한 서비스를 제공할지 선택의 문제가 발생한다. 본 연구는 무료와 유료 서비스가 공존하는 환경에서 구독과 단위당 구매의 탐색비용의 상대적 크기와 무료서비스 유지비용의 부담도에 따른 고품질과 저품질 무료 전략의 적합도를 분석한다. 나아가 경로의존적 소비자와 경로독립적 소비자군으로 구분된 확장 모형 분석 결과, 각 옵션 탐색비용의 상대적 크기에 따라 구독과 단위당 구매의 최적 가격이 결정됨을 보여준다. 구독의 탐색비용이 상대적으로 작은 경우에 경로의존적 소비자가 많아지고 경로독립적 소비자들의 유료전환에 대한 민감성이 커질수록 고품질의 무료서비스 제공이 우월한 전략임을 보인다. 반대로 구독의 상대적 탐색비용이 클 경우에는 경로의존적 소비자 수와 경로독립적 소비자들의 가격 민감성이 커질수록 저품질의 무료서비스 제공전략이 우월한 전략임을 확인한다.

The freemium model, widely used by IT companies today for rapid market penetration, offers consumers the opportunity to experience their products for free and generates revenue by selling premium features or products to those willing to pay. Typically, companies induce purchases for premium services through subscription or pay-per-use methods. They may initially offer a full version for free, then scale it down or offer a limited version encouraging purchases for premium features. This study highlights the suitability of high-quality or low-quality free strategies based on the relative exploration costs of subscription and pay-per-use in environments where free and paid services coexist. It further extends the model to path-dependent and path-independent consumer groups, showing that the optimal pricing for subscription and pay-per-use is determined by the relative size of search costs. When the search cost of a subscription is relatively small, the number of path-dependent consumers increases and the greater the sensitivity of path-independent consumers to paid conversion, high-quality free services dominate. However, when subscription search cost is high, low-quality free service strategies become more effective.

With the development of related technologies, Location-Based Services (LBS) are growing fast and being used in many ways. Past LBS studies have focused on adoption of LBS because of the fact that LBS users have privacy concerns regarding revealing their location information. Meanwhile, the number of LBS users and revenues from LBS are growing rapidly because users can get some benefits by revealing their location information. Little research has been done on how LBS affects consumers’ information search behavior in product purchase. The purpose of this paper is examining the effect of LBS information filtering on buyers’ uncertainty and their information search behavior. When consumers purchase a product, they try to reduce uncertainty by searching information. Generally, there are two types of uncertainties – knowledge uncertainty and choice uncertainty. Knowledge uncertainty refers to the lack of information on what kinds of alternatives are available in the market and/or their important attributes. Therefore, consumers having knowledge uncertainty will have difficulties in identifying what alternatives exist in the market to fulfil their needs. Choice uncertainty refers to the lack of information about consumers’ own preferences and which alternative will fit in their needs. Therefore, consumers with choice uncertainty have difficulties selecting best product among available alternatives.. According to economics of information theory, consumers narrow the scope of information search when knowledge uncertainty is high. It is because consumers’ information search cost is high when their knowledge uncertainty is high. If people do not know available alternatives and their attributes, it takes time and cognitive efforts for them to acquire information about available alternatives. Therefore, they will reduce search breadth. For people with high knowledge uncertainty, the information about products and their attributes is new and of high value for them. Therefore, they will conduct searches more in-depth because they have incentive to acquire more information. When people have high choice uncertainty, people tend to search information about more alternatives. It is because increased search breadth will improve their chances to find better alternative for them. On the other hand, since human’s cognitive capacity is limited, the increased search breadth (more alternatives) will reduce the depth of information search for each alternative. Consumers with high choice uncertainty will spend less time and effort for each alternative because considering more alternatives will increase their utility. LBS provides users with the capability to screen alternatives based on the distance from them, which reduces information search costs. Therefore, it is expected that LBS will help users consider more alternatives even when they have high knowledge uncertainty. LBS provides distance information, which helps users choose alternatives appropriate for them. Therefore, users will perceive lower choice uncertainty when they use LBS. In order to test the hypotheses, we selected 80 students and assigned them to one of the two experiment groups. One group was asked to use LBS to search surrounding restaurants and the other group was asked to not use LBS to search nearby restaurants. The experimental tasks and measures items were validated in a pilot experiment. The final measurement items are shown in Appendix A. Each subject was asked to read one of the two scenarios – with or without LBS – and use a smartphone application to pick a restaurant. All behaviors on smartphone were recorded using a recording application. Search breadth was measured by the number of restaurants clicked by each subject. Search depths was measured by two metrics – the average number of sub-level pages each subject visited and the average time spent on each restaurant. The hypotheses were tested using SPSS and PLS. The results show that knowledge uncertainty reduces search breadth (H1a). However, there was no significant correlation between knowledge uncertainty and search depth (H1b). Choice uncertainty significantly reduces search depth (H2b), but no significant relationship was found between choice uncertainty and search breadth (H2a). LBS information filtering significantly reduces the buyers’ choice uncertainty (H4) and reduces the negative relationship between knowledge uncertainty and search breadth (H3). This research provides some important implications for service providers. Service providers should use different strategies based on their service properties. For those service providers who are not well-known to consumers (high knowledge uncertainty) should encourage their customers to use LBS. This is because LBS would increase buyers’ consideration sets when the knowledge uncertainty is high. Therefore, less known services have chances to be included in consumers’ consideration sets with LBS. On the other hand, LBS information filtering decrease choice uncertainty and the near service providers are more likely to be selected than without LBS. Hence, service providers should analyze geographically approximate competitors’ strength and try to reduce the gap so that they can have chances to be included in the consideration set.

본 논문은 부정적 정보의 공개가 어떻게 단기간에 판매자의 수요를 증대시킬 수 있는지에 대한 경험적 분석을 통해 시장의 정보 불균형에 대한 중요한 이해를 제공하고자 한다. 이를 위해 본 연구는 기존의 관련 연구 결과에 더하여 정보 검색 비용이 부정적 정보 공개에 미치는 영향을 예측하고, 이러한 해석에 대하여 가상의 시장 거래를 통한 실험적 분석을 실시한다. 본 연구의 결과는 구매 위험도가 부정적 정보 검색에 중요한 역할을 하고 있는 반면 정보 검색 비용의 효과는 크지 않음을 나타내며, 특히 실험의 결과는 저품질의 제품을 판매하는 판매자가 어떻게 정보 공개를 통해 자신의 수익성 뿐 아니라 시장과 경쟁 제품의 수요를 증대시켜서 소비자 효용을 증대시킬 수 있는지를 보여준다.

This study has attempted to provide an important understanding about the information asymmetry in markets through empirical analysis on how the disclosure of low quality can increase demand even in the short run. More specifically, this study has extended the previous findings from the related literature by considering the effect of information search cost and providing empirical evidences about the effect of voluntary disclosure of low quality, using an experimental method with purchase scenarios. The results from our analysis show that reduced perceived risk have an important effect on sharing negative information, while the effect of information search cost is minimal. We also explain the circumstances whereby the information disclosure of a seller with low-quality product can enhance not only the seller’s profitability but also customers’ welfare by increasing the market demand and the demand for the seller claiming high quality.

In this paper, a Cuckoo Search Algorithm (CSA) is proposed for solving environmental economic load dispatch (EELD) problem with quadratic fuel function. Cuckoo Search is a new meta-heuristic algorithm inspired from the obligate brood parasitism of some cuckoo species by laying their eggs in the nests of other host birds of other species for solving optimization problems with promising results. However, Cuckoo Search has not been applied to EELD problem so far. Therefore, the paper presents application of CSA to the problem. The effectiveness of the proposed method is tested on several cases of dispatch and loads. The obtained result including fuel cost, emission and computation time from CSA are compared to those from other method reported in the paper. The comparison result has indicated that the proposed CSA is a very efficient method for solving EELD problem.

Labor managed firms typically require workers to invest capital and labor in a single venture. This will largely constrain the number of workers who are willing to and able to work in labor managed firms. Therefore, the labor search cost in labor managed firms would be higher than that of capital managed firms counterparts. As the number of workers increase the search cost will increase, and on the other hand, the agency problem advantage of labor managed firms would be diluted. The economic model introduced in this paper is founded on this simple idea. Using this framework, we show how variables such as number of workers, capital intensity, homogeneity of workers, labor turn-over ratio and riskiness can affect the emergence of labor managed firms. We also show why labor managed firms are often found to be more productive and when employee buy-out may occur.

리드솔로몬 복호기에서 4중 오류 이상의 오류치와 위치를 발견해 정정시는 보통 치엔탐색기를 사용한다. 이때 기존의 방법은 회로량이 많고 지연시간이 길어 비효율적이었다. 본 논문에서는 갈로이스 부분장을 이용 이 탐색기를 속도도 빠르고 회로량도 대폭 줄인 새로운 효율적 탐색기회로 설계법을 제시한다. 본 논문에서는 4중 오류위치를 정확히 추출함을 보였으나, 이새 설계된 탐색기회로는 5중이상의 오류위치도 정확히 찾을 수 있는 설계이다. 새로운 회로는 정확히 오류위치를 발견할 수 있음이 예를 통해 검증되었다.

In Reed Solomon decoder, when there are more than 4 error symbols, we usually use Chien search machine to find those error positions. In this case, classical method requires complex and relatively slow digital circuitry to implement it. In this paper we propose New fast and cost effective Chien search machine design method using Galois Subfield transformation. Example is given to show the method is working well. This new design can be applied to the case where there are more than 5 symbol errors in the Reed-Solomon code word.

In the telematics system, a reasonable path search time should be guaranteed from a great number of user's queries, even though the optimal path with minimized travel time might be continuously changed by the traffic flows. Thus, the path search method should consider traffic flows of the roads and the search time as well. However, the existing path search methods are not able to cope efficiently with the change of the traffic flows and to search rapidly paths simultaneously. This paper proposes a new path search method for fast computation. It also reflects the traffic flows efficiently. Especially, in order to simplify the computation of variable heuristic values, it employs a simplification method for estimating values of traffic-adaptable heuristics. The experiments are carried out with the $A^*$ algorithm and the proposed method in terms of the execution time, the number of node accesses and the accuracy. The results obtained from the experiments show that the method achieves very fast execution time and the reasonable accuracy as well.

오늘날 기업들이 전자상거래를 활용함으로써 얻을 수 있는 경제적인 효과는 매우 다양하다. 이에 전자상거래를 활용하는 업체의 효율적인 거래처 선정방법을 위한 정보검색비용절감 정도에 연구하고, 그에 따른 각각의 결과적인 실태를 분석하여 향후 전자상거래 활용기업에게 방향을 제시하고자 한다.

A quantitative analysis was conduct on the economic effect of electronic commerce according to the method of constructing the internet. As a consequence, it was information retrieval cost that had the most cost retrenchment effect in connecting the internet by telephone, which saved about 353,700 won. And it was found that the dedicated line to electronic commerce saved 420,600 won of information retrieval cost and a considerable amount of 319,900 won of brokerage expenses and physical distribution expenses. In terms of value, it was found that the telephone line reduced the time of order process by 8.25%, whereas the dedicated line did so by 9.41% and therefore saved more time than the telephone line. It was found that the dedicated line convenient to use had the higher effect by about 1.2%, respectively than the telephone line in terms of the effective construction of corporate image and the increase of potential buyers. In terms of business management, the intensification of corporate competitiveness improved by 10.00% in case of less than 10 times and by 11.53% in case of 50 to less than 50 times. And it was found that the effect of profit increase as the number of inquiries was large. That is, it was found that the effect of profit increase was 10.88% when the number of inquiries was less than 10 times but it increased to 14.00% in case of 50∼1ess than 100 times. The limitation of this study is that because the size of samples through mail, interview and E-mail was not large, its results have some limitation in applying them to every firm. That is, since the improvement effect of the intrafirm business method, unnecessary repeated manual paperwork and the use effect of being able to maintain the close relationship with to the parties to trades in the process of prompt receipt and delivery of documents are long-term and indirect effects, they have some limitation in that they can not be measured as coefficients but only as scales. Thus, firms using electronic commerce have difficulty enjoying a uniformly identical effect. Therefore, to revitalize electronic commerce, it is thought that government, the academic community and the business world all need to make much research into and sustained investment in electronic commerce.

The topic of this article is the use of trademarks for repaired luxury goods. The issue is what the test for the trademark infringement should be when defendant repairs and resells plaintiff’s used luxury goods without removing plaintiff’s trademark. Part II of this article introduces the search-cost theory, and explains that the function of trademarks is to decrease consumers’ search-cost of finding out unobservable features of a product and to give producers incentives to invest in maintaining the quality of their products. And it is also explained that the trademark right is necessary to guarantee the informative value of a trademark which embodies the information on the quality of its product, and that the search-cost theory can be the ground for the limitation of the trademark right as well as its entitlement. In Part III, the leading U.S. cases on the issue are introduced, and, in Part IV, it is demonstrated that the decisions in those cases can be justified by the search-cost theory, though there are some errors in the circuit court decision in ‘Rolex case.’ The court in ‘Rolex case’ erred in suggesting that the identity of repaired luxury goods is the function of technological importance, not taking account of the consumer's desire of expressive use.

이 연구는 가치-태도-행동(Value-Attitude-Behavior, VAB) 모델을 적용하여 식물성 대체식품에 대한 소비자행동을 실증적으로 분석하였다. 300명의 응답 자료를 바탕으로 SPSS와 AMOS를 활용하여 구조방정식모형(SEM) 분석을수행하고, 다중집단분석(MGA)을 통해 탐색 비용의 조절 효과를 검증하였다. 분석 결과, 식물성 대체식품의 지각된 가치중 감정적 가치, 경제적 가치, 윤리적 가치 모두 태도에 유의한 영향을 미쳤으며, 이 중 경제적 가치의 영향력이 가장크게 나타났다. 또한 태도는 구매 의도에, 구매 의도는 구전 의도에 각각 유의한 영향을 미쳤다. 행동 의도의 구조적타당성을 검증하기 위해 태도→구매 의도→구전 의도의 단계적 구조(모형 A)와 태도가 구매 의도 및 구전 의도에 직접영향을 미치는 병렬적 구조(모형 B)를 경쟁모형으로 설정하여 비교하였다. 주요 적합도 지수를 종합적으로 고려한 결과, 단계적 구조를 가정한 모형 A가 상대적으로 우수한 것으로 나타나 최종 연구 모형으로 채택하였다. 한편, 탐색 비용수준(고/저)에 따른 다중집단분석 결과, 감정적 가치와 경제적 가치에서 태도로 이어지는 경로에서 집단 간 유의한 차이가 확인되었으나, 윤리적 가치에서 태도로 이어지는 경로에서는 유의한 차이가 나타나지 않았다. 이러한 결과는 탐색 비용수준이 소비자의 가치 인식과 태도 형성에 영향을 미칠 수 있음을 보여주며, 마케팅 전략 수립 시 경제적 가치를 강조한 차별화된 접근의 필요성을 시사한다.

This study empirically analyzed consumer behavior toward plant-based alternative foods by applying the Value?Attitude?Behavior (VAB) model. Based on survey data from 300 respondents, structural equation modeling (SEM) was conducted using SPSS and AMOS, and multi-group analysis (MGA) was employed to verify the moderating effect of search cost. The results showed that among the perceived value dimensions, emotional economic, and ethical value all had a significant effect on attitude, with economic value exerting the strongest influence. In addition, attitude significantly influenced purchase intention, which in turn significantly affected word-of-mouth intention. To examine the structural validity of behavioral intention, a sequential structure in which attitude leads to purchase intention and subsequently to word-of-mouth intention (Model A) and a parallel structure in which attitude directly influences both purchase intention and word-of-mouth intention (Model B) were compared. Considering the overall model fit indices, Model A showed relatively better fit and was adopted as the final model. The multi-group analysis revealed significant differences between high and low search cost groups in the paths from emotional and economic value to attitude, whereas the path from ethical value to attitude did not show a significant difference between groups. These findings indicate that search cost can shape consumers’ value perceptions and attitude formation, highlighting the need for differentiated marketing strategies that emphasize economic value.

선박경제운항이란 기상예측정보를 활용하여 연료소모량을 최소화하도록 선박을 운항하는 것으로서 최근 다양한 선박경제운항 시스템이 연구되고 있다. 성공적인 선박경제운항을 위해서는 효율적인 최적의 지리적 경로탐색 방법이 필요한데 기존의 시스템에서는 주로 Dijkstra 알고리즘 기반의 최소정적비용 경로탐색 알고리즘으로 접근하고 있다. 그러한 접근법을 적용하기 위해서는 특히 연료소모량으로 정의되는 간선의 비용을 고정해야 하는데 선박이 그 간선을 실제 지날 때의 기상 상황에 따라 연료소모량이 변할 수 있다는 점에서 적절하지 않은 가정이다. 이에본 논문에서는 그러한 단점을 극복하기 위해 Dijkstra 알고리즘을 변형한 최소동적비용 경로탐색 알고리즘을 제안한다. 또한, 실행시간을 단축하기 위해 A* 알고리즘을 활용하여 탐색공간을 효과적으로 줄이기 위한 방법도 제시한다. 총 10개의 테스트 노선에 대해서 본 논문에서 제안된 시스템을 기존의 단순한 최단거리 운항방법과 비교한 결과, 운항소요시간은 거의 차이가 없으면서도 연료소모량을 평균 2.36%, 최대 4.82% 개선시킬 수 있었다.

An economic ship routing means to sail a ship with a goal of minimizing the fuel consumption by utilizing weather forecast information, and various such systems have been recently studied. For a successful economic ship routing system, an efficient algorithm is needed to search an optimal geographical path, and most of the previous systems were approaching to that problem through a minimal static-cost path search algorithm based on the Dijkstra algorithm. To apply that kind of search algorithm, the cost of every edge assigned with the estimated fuel consumption should be constant. However, that assumption is not practical at all considering that the actual fuel consumption is determined by the weather condition when the ship will pass the edge. To overcome such a limitation, we propose a new optimal ship routing system based on a minimal dynamic-cost path search algorithm by properly modifying the Dijkstra algorithm. In addition, we propose a method which efficiently reduces the search space by using the A* algorithm to decrease the running time. We compared our system with the shortest path-based sailing method over ten testing routes and observed that the former reduced the estimated fuel consumption than the latter by 2.36% on average and the maximum 4.82% with little difference of estimated time of arrival.

본 연구의 목적은 관광자가 지닌 관광지에 관한 전문성이 관광정보탐색비용을 감소시킨다는 Gursoy & McCleary(2004)의 구조 모델 중 (1) 전문성과 외부정보탐색비용과 내부정보탐색비용에 관한 모델을 적용하여 실증연구를 통한 관계를 고찰하는 것이며, (2) 모바일을 활용한 관광정보탐색은 정보탐색비용에 어떠한 영향을 미치는지 그 조절효과를 검정하는 데 있다. 이론적 모형 및 구성개념은 기존 연구를 통하여 도출되었으며, 제안모형의 가설을 검정하기 위하여 서울 시내 대학생을 대상으로 실증조사가 이루어졌다. 설문조사를 통해 수집된 총 283명의 자료는 SPSS를 활용한 회귀분석으로 분석되었으며, 그 결과는 다음과 같다. 첫째, 관광지 전문성은 외부정보탐색비용을 증가시켰으며 그 중 관광지에 대한 사전지식이 외부정보탐색비용에 유의한 효과를 나타냈다, 둘째, 관광지 전문성은 내부정보탐색비용에 정(+)의 방향으로 유의하게 작용하였으며, 관광지에 대한 사전지식 및 관광지 결정에 대한 본인의 의사결정이 내부정보탐색비용을 증가시켰다. 셋째, 관광지 정보탐색의 모바일 활용은 외부정보탐색비용과 내부정보탐색비용을 감소시키는 효과를 나타냈으나, 관광지 전문성과의 상호작용효과는 검정되지 않았다. 이와 같은 결과를 토대로 대안모형을 설정하였으며, 실증분석 결과에 대한 학문적 시사점과 실무적 시사점을 제시하였다.

The purposes were to (1) examine the effect of destination expertise on cost of external information search and cost of internal information search and (2) verify the moderating role of mobile usage for destination information search. The conceptual model was designed based on previous literature review and the model was tested empirically. Data collected from 283 undergraduate were analyzed using regression. The findings of this research revealed that the higher destination expertise, the higher costs of both external and internal information search. In addition, the moderating role of mobile usage for destination information search was significant between destination expertise and cost of external/internal information search. Alternative model was identified and academic and practical implications were provided.

결함허용 시스템은 다양한 형태의 중복을 사용하여 신뢰도를 향상시킬 수 있는 반면, 시스템의 비용을 크게 증가시킨다. 본 논문은 만족스러운 신뢰도를 갖추면서 추가 비용을 적게 요구하는 결함허용 컴퓨터 시스템의 구조를 결정하기 위한 설계 문제를 정의하고 탐색에 기반을 둔 해결법을 제안한다. 이 때, 탐색 기법이 방문하는 탐색 공간의 크기를 줄이기 위하여 사용되는 세 가지의 유용한 사실을 설명한다. 이를 바탕으로 삼중 모듈 중복(TMR: Triple-Modular-Redundancy), 백업 예비(backup sparing), 그리고 혼합 중복(hybride redundancy) 기법과 같은 결함허용 기법들이 시스템 구조에 적용되었을 때, 탐색 공간을 줄이는 용도로 사용될 수 있는 신뢰도 제약조건을 유도해낸다.

일반적으로 수중 센서 네트워크에서 모든 센서 노드는 위치가 결정된 앵커 노드를 이용하여 자신의 위치를 결정한다. 본 논문에서는 수중 센서 네트워크에서 모든 센서 노드의 위치를 결정하기 위해 최소의 수를 가진 앵커 노드를 결정하기 위한 타부 서치 알고리즘을 제안한다. 네트워크에서 센서 노드의 수가 증가함에 따라 앵커 노드의 수를 결정하는 계산량은 급격히 늘어나게 된다. 본 논문에서는 밀집도가 높은 네트워크에서 적정한 시간 내에 최소의 앵커 노드수를 결정하는 타부 서치 알고리즘을 제안하며, 효율적인 검색을 위해 타부 서치 알고리즘의 효과적인 이웃해 생성 동작을 제안한다. 제안된 알고리즘은 최소 앵커 노드의 수와 실행시간 관점에서 성능을 평가하며, 평가 결과에서 제안된 알고리즘이 기존의 알고리즘에 비해 성능이 5-10% 우수함을 보인다.

All sensor nodes generally determine their positions using anchor nodes that are located in underwater sensor networks. This paper proposes a Tabu search algorithm to determine the minimum number of anchor nodes for the location of all sensor nodes in underwater sensor networks. As the number of the sensor nodes increases in the network, the amount of calculation that determines the number of anchor nodes would be too much increased. In this paper, we propose a Tabu search algorithm that determines the minimum number of anchor nodes within a reasonable computation time in a high dense network, and propose an efficient neighborhood generating operation of the Tabu search algorithm for efficient search. The proposed algorithm evaluates those performances through some experiments in terms of the minimum number of anchor nodes and execution time. The proposed algorithm shows 5-10% better performance than the conventional algorithm.

경찰은 실종자 수색과 구조를 위하여 실종자 수색에 특화된 드론을 정식 도입하면서 전문 운용인력도 채용하고 있다. 기존의 인력과 헬기 중심의 수색 방식에서 드론을 활용한 수색으로의 전환이 이루어지고 있는데, 이러한 정책결정이 한정된 경찰 예산을 효율적으로 사용하고 있는지에 대한 기존의 연구는 국내⋅외적으로 거의 없는 실정이다. 본 연구에서는 실제 발생한 3건의 실종사건 사례를 기반으로 인력과 헬기 중심의 수색과 드론을 활용한 수색에 대한 비용과 편익을 비교하였다. 이와 더불어 효과적인 드론 활용을 위한 수색방식을 제안하고자 하였다. 아울러 드론을 활용한 실종자 수색에서 제기될 수 있는 사생활 침해에대해서도 윤리적인 검토를 실시하였다. 결과적으로 드론을 활용한 실종자 수색은 비용보다는 편익이 높은 것으로 나타났으며 기존의방식보다 편익이 높기 때문에 드론 활용을 보다 확대할 필요가 있음을 보여주고 있다. 비록 사생활 침해 등의 요소 등 보다는 실종자 생명을 구한다는 편익이 크기는 하나 드론 활용으로 야기되는 문제에 대한 보완 방안이 필요할 것이다. 본 연구는 3가지 사례만을 분석하였는 바, 보다 많은사례에 대한 분석을 통하여 드론 활용에 따른 비용과 편익 분석을 더욱 정확하게 산출하는 것이 필요할 것이다

Korean police have officially introduced drones specialized in searching for and rescuing missingpersons, and are also hiring professional operators. The transition from the existing personnel andhelicopter-oriented search methods to drone-based search is taking place, but there is little domestic orforeign research on whether such policy decisions are using limited police budgets efficiently. In this study, the cost and benefits of the search and rescue drones, and personnel andhelicopter-centered search were compared based on the three actual missing cases. In addition, weproposed a search method for effective drone utilization. Moreover, ethical review was conducted on thepossible infringement of privacy that could be raised in the search for missing persons using drones. As a result, the search for missing persons using drones has shown that the benefits are higher thanthe costs, and that it is necessary to expand the use of drones further because the benefits are higher thanthe existing methods. Although the benefits of saving the lives of missing persons are large rather thanfactors such as invasion of privacy, supplementary measures will be needed for problems caused by theuse of drones. Since this study analyzed only three cases, it is necessary to more accurately calculate thecost and benefits of using drones through analysis of more cases.

충돌 피항 동작은 선박 간 끊임없이 영향을 주고받는다. 특히 다수의 선박이 조우하는 경우, 상대 선박의 피항 의도를 파악하고 서로에게 얼마나 영향을 미치는 지를 파악하는 것은 어려운 일이다. 이를 위해 분산 확률 탐색 알고리즘이 제안되었다. 분산 확률 탐색 알고리즘은 이웃 선박과 반복적인 메시지 교환을 통해 비용을 가장 크게 낮출 수 있는 코스를 탐색 후 확률과 제한 조건에 따라 기존의 코스를 유지할지 아니면 새로운 코스를 선택할지를 결정한다. 그러나 분산 확률 탐색 알고리즘에 사용된 파라미터가 충돌 피항에 어떠한 영향을 미치는지 증명되지 않았다. 본 논문에서는 분산 확률 탐색 알고리즘의 파라미터와 가중치가 충돌 피항에 어떠한 영향을 미치는지 분석하였다. 또한 타선과의 피항 거리를 조절하기 위한 충격 흡수 영역을 소개한다. 실험 방법은 두 선박이 조우할 수 있는 세 가지 상황, 즉 정면에서 조우하는 상황, 횡단하는 상황, 추월하는 상황에 파라미터와 가중치의 변수들을 조합하여 실험을 진행하였다. 각 상황 당 8,000회, 총 24,000회의 실험이 진행되었다. 실험 결과 모든 실험에서 한 건의 충돌도 발생하지 않았다. 선박이 목적지에 큰 가중치를 줄 경우, 즉 이기적인 행동을 할 경우, 비용은 증가함을 보였다. 타선의 움직임을 더 길게 예측할수록 항행 거리, 메시지 교환 횟수는 작아지는 경향을 보였다.

When using a distributed system, it is very important to know the intention of a target ship in order to prevent collisions. The action taken by a certain ship for collision avoidance and the action of the target ship it intends to avoid influence each other. However, it is difficult to establish a collision avoidance plan in consideration of multiple-ship situations for this reason. To solve this problem, a Distributed Stochastic Search Algorithm (DSSA) has been proposed. A DSSA searches for a course that can most reduce cost through repeated information exchange with target ships, and then indicates whether the current course should be maintained or a new course should be chosen according to probability and constraints. However, it has not been proven how the parameters used in DSSA affect collision avoidance actions. Therefore, in this paper, I have investigated the effect of the parameters and weight factors of DSSA. Experiments were conducted by combining parameters (time window, safe domain, detection range) and weight factors for encounters of two ships in head-on, crossing, and overtaking situations. A total of 24,000 experiments were conducted: 8,000 iterations for each situation. As a result, no collision occurred in any experiment conducted using DSSA. Costs have been shown to increase if a ship gives a large weight to its destination, i.e., takes selfish behavior. The more lasting the expected position of the target ship, the smaller the sailing distance and the number of message exchanges. The larger the detection range, the safer the interaction.

The sponsored search has become significant channel of online advertising, and the large sized advertisers have appeared, so the sponsored search strategy is becoming more important. Since CPC(Cost-per-Click) advertising has different price according to keyword, it is difficult to manage the a lot of keywords at one time. So, the purpose of this study is to investigate the factors which influence on the cost-per-click of sponsored search advertising. That is, there are four factors: impression, CTR(Click through Rate), conversion rate, and keyword's length. for the regression analysis, we use the actual data which is gotten from an ad agency. The result of that, the impression and keyword's length influence cost-per-click positively. However, CTR & conversion rate have no influence on it unexpectedly.

본 연구는 4차 산업혁명의 핵심 기술중의 하나인 드론이 공공영역에서 활용될 경우의 사회적 비용과 편익에 대해 분석을 실시하였다. 공공영역 활용 드론중 비교적 빠르게 현장에서 활용중인 경찰의 실종자 수색용 드론을 중심으로 논의를 전개하였다. 정부는 재난, 치안, 공공건설 등 다양한 공적 분야에서 드론을 활용할 계획을 세우고 집중적인 지원을 실시하고 있다. 본 연구에서는 이렇게 지원이 집중되고 있는 드론에 대한 최초의 사회적 비용·편익 분석을 실시하였다는데 그 의의가 있다고 할 수 있다. 분석에 따르면 드론을 활용할 경우 기존의 인력중심의 수색에 비하여 비용의 경우 1/10 수준이며, 인력은 1/7 수준으로 나타났다. 드론의 기술이 급속하게 발달하고 있는 만큼, 비용과 인력의 절감은 더욱 커 질것으로 예상이 된다. 비용과 인력의 절감과 더불어 수색인력의 손실을 방지할 수 있으며, 무엇보다도 광범위한 범위를 빠른 시간내에 수색할 수 있고, 구조 인력이 접근하기 어려운 지역까지 수색이 가능하여 실종자가 사망하기 전에 발견할 수 있는 무형의 편익이 있다. 그러나 본 연구는 기존의 자료가 없기 때문에 실종자 수색 1건을 대상으로 분석을 실시하여 외적타당도에 한계가 있을 수 있다. 향후 연구에서는 자료의 수집과 실증적인 연구를 통해 보다 정확한 비용과 편익이 이루어져야 할 것이다.

This study performed the social cost - benefit analysis of public drones which is one of the key technologies of the 4th Industrial Revolution. The discussion focused on the police's search for missing persons, which were being utilized on the site, among the drones used in the public sector. The government plans to use drones in various public sectors such as disaster, police, and public construction and is implementing intensive support. This research is meaningful in that it conducted the first social cost-benefit analysis for these supporting drones. The analysis indicates that the cost of using drones is about one-tenth of the cost compared to the existing search centered on human resources, and that the manpower is 1/7th. With the rapid development of drone technology, the cost and labor savings are expected to be even greater. There are intangible benefits that can be found before the death of a missing person, including the reduction of cost and manpower, the rapid search of a wide range of people, and, among other things, searchable areas that are difficult for rescue workers to access. However, since this research does not have existing data, there may be limitations in external validity by conducting an analysis on one missing case. Future research will require more accurate costs and benefits from data collection and empirical research.