• Title/Summary/Keyword: multiple returns

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Research of the Delivery Autonomy and Vision-based Landing Algorithm for Last-Mile Service using a UAV (무인기를 이용한 Last-Mile 서비스를 위한 배송 자동화 및 영상기반 착륙 알고리즘 연구)

  • Hanseob Lee;Hoon Jung
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.46 no.2
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    • pp.160-167
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    • 2023
  • This study focuses on the development of a Last-Mile delivery service using unmanned vehicles to deliver goods directly to the end consumer utilizing drones to perform autonomous delivery missions and an image-based precision landing algorithm for handoff to a robot in an intermediate facility. As the logistics market continues to grow rapidly, parcel volumes increase exponentially each year. However, due to low delivery fees, the workload of delivery personnel is increasing, resulting in a decrease in the quality of delivery services. To address this issue, the research team conducted a study on a Last-Mile delivery service using unmanned vehicles and conducted research on the necessary technologies for drone-based goods transportation in this paper. The flight scenario begins with the drone carrying the goods from a pickup location to the rooftop of a building where the final delivery destination is located. There is a handoff facility on the rooftop of the building, and a marker on the roof must be accurately landed upon. The mission is complete once the goods are delivered and the drone returns to its original location. The research team developed a mission planning algorithm to perform the above scenario automatically and constructed an algorithm to recognize the marker through a camera sensor and achieve a precision landing. The performance of the developed system has been verified through multiple trial operations within ETRI.

Aircraft application with artificial fuzzy heuristic theory via drone

  • C.C. Hung;T. Nguyen;C.Y. Hsieh
    • Advances in aircraft and spacecraft science
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    • v.10 no.6
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    • pp.495-519
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    • 2023
  • The drone serves the customers not served by vans. At the same time, considering the safety, policy and terrain as well as the need to replace the battery, the drone needs to be transported by truck to the identified station along with the parcel. From each such station, the drone serves a subset of customers according to a direct assignment pattern, i.e., every time the drone is launched, it serves one demand node and returns to the station to collect another parcel. Similarly, the truck is used to transport the drone and cargo between stations. This is somewhat different from the research of other scholars. In terms of the joint distribution of the drone and road vehicle, most scholars will choose the combination of two transportation tools, while we use three. The drone and vans are responsible for distribution services, and the trucks are responsible for transporting the goods and drone to the station. The goal is to optimize the total delivery cost which includes the transportation costs for the vans and the delivery cost for the drone. A fixed cost is also considered for each drone parking site corresponding to the cost of positioning the drone and using the drone station. A discrete optimization model is presented for the problem in addition to a two-phase heuristic algorithm. The results of a series of computational tests performed to assess the applicability of the model and the efficiency of the heuristic are reported. The results obtained show that nearly 10% of the cost can be saved by combining the traditional delivery mode with the use of a drone and drone stations.

Waiting Time and Sojourn Time Analysis of Discrete-time Geo/G/1 Queues under DT-policy (DT-정책 하에서 운영되는 이산시간 Geo/G/1 시스템의 대기시간과 체재시간 분석)

  • Se Won Lee
    • Journal of Korea Society of Industrial Information Systems
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    • v.29 no.2
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    • pp.69-80
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    • 2024
  • In this paper, we studied a discrete-time queuing system that operates under a mixed situation of D-policy and T-policy, one of the representative server control policies in queuing theory. A single server serves customers arriving by Bernoulli arrival process on a first-in, first-out basis(FIFO). If there are no customers to serve in the system, the server goes on vacation and returns, until the total service time (i.e., total amount of workload) of waiting customers exceeds predetermined workload threshold D. The operation of the system covered in this study can be used to model the efficient resource utilization of mobile devices using secondary batteries. In addition, it is significant in that the steady state waiting time and system sojourn time of the queuing system under a flexible mixed control policy were derived within a unified framework.

Efficient and Privacy-Preserving Near-Duplicate Detection in Cloud Computing (클라우드 환경에서 검색 효율성 개선과 프라이버시를 보장하는 유사 중복 검출 기법)

  • Hahn, Changhee;Shin, Hyung June;Hur, Junbeom
    • Journal of KIISE
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    • v.44 no.10
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    • pp.1112-1123
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    • 2017
  • As content providers further offload content-centric services to the cloud, data retrieval over the cloud typically results in many redundant items because there is a prevalent near-duplication of content on the Internet. Simply fetching all data from the cloud severely degrades efficiency in terms of resource utilization and bandwidth, and data can be encrypted by multiple content providers under different keys to preserve privacy. Thus, locating near-duplicate data in a privacy-preserving way is highly dependent on the ability to deduplicate redundant search results and returns best matches without decrypting data. To this end, we propose an efficient near-duplicate detection scheme for encrypted data in the cloud. Our scheme has the following benefits. First, a single query is enough to locate near-duplicate data even if they are encrypted under different keys of multiple content providers. Second, storage, computation and communication costs are alleviated compared to existing schemes, while achieving the same level of search accuracy. Third, scalability is significantly improved as a result of a novel and efficient two-round detection to locate near-duplicate candidates over large quantities of data in the cloud. An experimental analysis with real-world data demonstrates the applicability of the proposed scheme to a practical cloud system. Last, the proposed scheme is an average of 70.6% faster than an existing scheme.

Analysis Method for Full-length LiDAR Waveforms (라이다 파장 분석 방법론에 대한 연구)

  • Jung, Myung-Hee;Yun, Eui-Jung;Kim, Cheon-Shik
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.44 no.4 s.316
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    • pp.28-35
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    • 2007
  • Airbone laser altimeters have been utilized for 3D topographic mapping of the earth, moon, and planets with high resolution and accuracy, which is a rapidly growing remote sensing technique that measures the round-trip time emitted laser pulse to determine the topography. The traveling time from the laser scanner to the Earth's surface and back is directly related to the distance of the sensor to the ground. When there are several objects within the travel path of the laser pulse, the reflected laser pluses are distorted by surface variation within the footprint, generating multiple echoes because each target transforms the emitted pulse. The shapes of the received waveforms also contain important information about surface roughness, slope and reflectivity. Waveform processing algorithms parameterize and model the return signal resulting from the interaction of the transmitted laser pulse with the surface. Each of the multiple targets within the footprint can be identified. Assuming each response is gaussian, returns are modeled as a mixture gaussian distribution. Then, the parameters of the model are estimated by LMS Method or EM algorithm However, each response actually shows the skewness in the right side with the slowly decaying tail. For the application to require more accurate analysis, the tail information is to be quantified by an approach to decompose the tail. One method to handle with this problem is proposed in this study.

WHICH INFORMATION MOVES PRICES: EVIDENCE FROM DAYS WITH DIVIDEND AND EARNINGS ANNOUNCEMENTS AND INSIDER TRADING

  • Kim, Chan-Wung;Lee, Jae-Ha
    • The Korean Journal of Financial Studies
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    • v.3 no.1
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    • pp.233-265
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    • 1996
  • We examine the impact of public and private information on price movements using the thirty DJIA stocks and twenty-one NASDAQ stocks. We find that the standard deviation of daily returns on information days (dividend announcement, earnings announcement, insider purchase, or insider sale) is much higher than on no-information days. Both public information matters at the NYSE, probably due to masked identification of insiders. Earnings announcement has the greatest impact for both DJIA and NASDAQ stocks, and there is some evidence of positive impact of insider asle on return volatility of NASDAQ stocks. There has been considerable debate, e.g., French and Roll (1986), over whether market volatility is due to public information or private information-the latter gathered through costly search and only revealed through trading. Public information is composed of (1) marketwide public information such as regularly scheduled federal economic announcements (e.g., employment, GNP, leading indicators) and (2) company-specific public information such as dividend and earnings announcements. Policy makers and corporate insiders have a better access to marketwide private information (e.g., a new monetary policy decision made in the Federal Reserve Board meeting) and company-specific private information, respectively, compated to the general public. Ederington and Lee (1993) show that marketwide public information accounts for most of the observed volatility patterns in interest rate and foreign exchange futures markets. Company-specific public information is explored by Patell and Wolfson (1984) and Jennings and Starks (1985). They show that dividend and earnings announcements induce higher than normal volatility in equity prices. Kyle (1985), Admati and Pfleiderer (1988), Barclay, Litzenberger and Warner (1990), Foster and Viswanathan (1990), Back (1992), and Barclay and Warner (1993) show that the private information help by informed traders and revealed through trading influences market volatility. Cornell and Sirri (1992)' and Meulbroek (1992) investigate the actual insider trading activities in a tender offer case and the prosecuted illegal trading cased, respectively. This paper examines the aggregate and individual impact of marketwide information, company-specific public information, and company-specific private information on equity prices. Specifically, we use the thirty common stocks in the Dow Jones Industrial Average (DJIA) and twenty one National Association of Securities Dealers Automated Quotations (NASDAQ) common stocks to examine how their prices react to information. Marketwide information (public and private) is estimated by the movement in the Standard and Poors (S & P) 500 Index price for the DJIA stocks and the movement in the NASDAQ Composite Index price for the NASDAQ stocks. Divedend and earnings announcements are used as a subset of company-specific public information. The trading activity of corporate insiders (major corporate officers, members of the board of directors, and owners of at least 10 percent of any equity class) with an access to private information can be cannot legally trade on private information. Therefore, most insider transactions are not necessarily based on private information. Nevertheless, we hypothesize that market participants observe how insiders trade in order to infer any information that they cannot possess because insiders tend to buy (sell) when they have good (bad) information about their company. For example, Damodaran and Liu (1993) show that insiders of real estate investment trusts buy (sell) after they receive favorable (unfavorable) appraisal news before the information in these appraisals is released to the public. Price discovery in a competitive multiple-dealership market (NASDAQ) would be different from that in a monopolistic specialist system (NYSE). Consequently, we hypothesize that NASDAQ stocks are affected more by private information (or more precisely, insider trading) than the DJIA stocks. In the next section, we describe our choices of the fifty-one stocks and the public and private information set. We also discuss institutional differences between the NYSE and the NASDAQ market. In Section II, we examine the implications of public and private information for the volatility of daily returns of each stock. In Section III, we turn to the question of the relative importance of individual elements of our information set. Further analysis of the five DJIA stocks and the four NASDAQ stocks that are most sensitive to earnings announcements is given in Section IV, and our results are summarized in Section V.

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Web-based Measurement of ECU Signals on Vehicle using Embedded Linux

  • Choi, Kwang-Hun;Lee, Lee;Lee, Young-Choon;Kwon, Tae-Kyu;Lee, Seong-Cheol
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.138-142
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    • 2004
  • In this paper, we present a new method for monitoring of ECU's sensor signals of vehicle. In order to measure the ECU's sensor signals, the interfaced circuit is designed to communicate ECU and the Embedded Linux is used to monitor communication result through Web the Embedded Linux system and this system is said "ECU Interface Part". In ECU Interface Part the interface circuit is designed to match voltage level between ECU and SA-1110 micro controller and interface circuit to communicate ECU according to the ISO, SAE communication protocol standard. Because Embedded Linux does not allow to access hardware directly in application level, anyone who wants to modify any low level hardware must develop device driver. To monitor ECU's sensor signals the most important thing is to match serial level between ECU and ECU Interface Part. It means to communicate correctly between two hardware we need to match voltage and signal level, and need to match baudrate. The voltage of SA-1110 is 0 ${\sim}$ +3.3V and ECU is 0 ${\sim}$ +12V and, ECU's communication Line K does multiple operation so, the interface circuit is used to match voltage and signal level. In Addition to ECU's baudrate is 10400bps, it's not standard baudrate in computer environment. So, we need to develop a device driver to control the interface circuit, and change baudrate. To monitor ECU's sensor signals through web there's a network socket program is working in Embedded Linux. It works as server program and manages user's connections and commands. Anyone who wants to monitor ECU's sensor signals he just only connect to Embedded Linux system with web browser then, Embedded Linux webserver will return the ActiveX webbased measurement software. It works in web browser and inits ECU, as a result it returns sensor signals through web. All the programs are developed with GCC(GNU C Compiler) and, webbased measurement software is developed with Borland C++ Builder.

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Art and Collectivity (미술과 집단성)

  • Kwok, Kian-Chow
    • The Journal of Art Theory & Practice
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    • no.4
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    • pp.181-202
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    • 2006
  • "When it comes to art, nationalism is a goodticket to ride with", says the title of a report in the Indian Express (Mumbai, 29 Oct 2000). The newspaper report goes on to say that since Indian art was kept "ethnic" by colonialism, national liberation meant opening up to the world on India's own terms. Advocacy, at the tail end of the 20th century, would contrast dramatically with the call by Rabindranath Tagore, the founder of the academy at Santiniketan in 1901, to guard against the fetish of nationalism. "The colourless vagueness of cosmopolitanism," Tagore pronounced, "nor thefierce self-idolatry of nation-worship, is the goal of human history" (Nationalism, 1917). This contrast is significant on two counts. First is the positive aspect of "nation" as a frame in art production or circulation, at the current point of globalization when massive expansion of cultural consumers may be realized through prevailing communication networks and technology. The organization of the information market, most vividly demonstrated through the recent FIFA World Cup when one out of every five living human beings on earth watched the finals, is predicated on nations as categories. An extension of the Indian Express argument would be that tagging of artworks along the category of nation would help ensure greatest reception, and would in turn open up the reified category of "art," so as to consider new impetus from aesthetic traditions from all parts of the world many of which hereto fore regarded as "ethnic," so as to liberate art from any hegemony of "international standards." Secondly, the critique of nationalism points to a transnational civic sphere, be it Tagore's notion of people-not-nation, or the much mo re recent "transnational constellation" of Jurgen Habermas (2001), a vision for the European Union w here civil sphere beyond confines of nation opens up new possibilities, and may serve as a model for a liberated sphere on global scale. There are other levels of collectivity which art may address, for instance the Indonesian example of local communities headed by Ketua Rukun Tetangga, the neighbourhood headmen, in which community matters of culture and the arts are organically woven into the communal fabric. Art and collectivity at the national-transnational level yield a contrasting situation of, on the idealized end, the dual inputs of local culture and tradition through "nation" as necessary frame, and the concurrent development of a transnational, culturally and aesthetically vibrant civic sphere that will ensure a cosmopolitanism that is not a "colourless vagueness." In art historical studies, this is seen, for instance, in the recent discussion on "cosmopolitan modernisms." Conversely, we may see a dual tyranny of a nationalism that is a closure (sometimes stated as "ethno-nationalism" which is disputable), and an internationalism that is evolved through restrictive understanding of historical development within privileged expressions. In art historical terms, where there is a lack of investigation into the reality of multiple modernisms, the possibility of a democratic cosmopolitanism in art is severely curtailed. The advocacy of a liberal cosmopolitanism without a democratic foundation returns art to dominance of historical privileged category. A local community with lack of transnational inputs may sometimes place emphasis on neo-traditionalism which is also a double edged sword, as re kindling with traditions is both liberating and restrictive, which in turn interplays with the push and pull of the collective matrix.

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The Impact of M&A of Small and Medium-Sized Companies on Merger Disclosure Effect and Long-Term Operating Performance (중소기업의 M&A가 합병 공시효과와 장기 영업성과에 미치는 영향)

  • Kim, Byoung_jin;Jung, Jin-young
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.12 no.6
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    • pp.49-63
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    • 2017
  • The purpose of this study is to analyze the effects of the collective characteristics of SMEs on M&A activity on the disclosure effect of mergers and long-term business performance after mergers. From 2000 to 2012, we examine 717 cases of small and medium-sized enterprises (SMEs) using multiple regression analysis and difference analysis. The results of this study are as follows. First, it is confirmed that the effect on the merger announcement effect is the same as the previous study on the Korean capital market listed companies except for the effect of diversification, listing effect, and cross-border effect. In addition, we have found that firms with higher performance in the past have higher excess returns in the disclosure effect of mergers and acquisitions. Second, unlike the previous studies that non-related mergers have a positive effect on long-term operating performance, for the characteristics of SMEs with lower market competitiveness than that of average listed companies, SMEs merging with same industry group companies have a positive effect on long-term operating performance. This study provides a new perspective on the merger and acquisition of SMEs by examining the effects of M&A announcement and long-term performance.

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Determinants of Credit Default Swap Spreads: The Case of Korean Firms (한국 기업들의 신용부도스왑 스프레드에 대한 결정요인 분석)

  • Park, Yoon-S.;Kim, Han-Joon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.10
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    • pp.4359-4368
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    • 2011
  • Among several macroeconomic missteps blamed for the recent global financial crisis including the social problems of income distribution and the lack of proper financial remedies, two of them have received particular attention: the global BOP(Balance of Payment) imbalance and the misguided monetary policy. Such BOP imbalance was blamed for massive foreign exchange investment flows from Asia into the U.S., triggering the financial and real estate bubble in America. The latter refers to the excessively loose monetary policy of the U.S. Federal Reserve, which pushed financial institutions and households into reckless investment behavior in search of higher returns. Given the abuse of certain innovative financial techniques and new investment instruments that have been created in recent decades, both collateralized debt obligations (CDOs) and credit default swaps (CDS) enjoyed a symbiotic and toxic relationship prior to the financial crisis This paper is organized as follows: The first section analyzes the real causes of the recent financial crisis. The second details the role of CDOs and CDS. Then, to identify key determinants of the CDS spreads in an emerging capital market, the sample data of major Korean firms' CDS spreads are used to estimate the risk premium by utilizing the multiple regression analysis. The empirical test result indicates that Korean 3-year treasury bond rate(TYIELD), market to book value ratio(MV/BV), and assets size(INASSETS) are shown to demonstrate statistically significant influences on the changes of the CDS premium for sample firms.