• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.10
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• pp.4886-4907
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• 2019

The use of mobile devices is increasing in multimedia applications. The multimedia contents are delivered to mobile users over heterogeneous networks. Due to fluctuation in bandwidth and user mobility, the service providers are facing difficulties in providing Quality of Service (QoS) guaranteed delivery for multimedia applications. Multimedia applications depend on QoS parameters such as delay, bandwidth, and jitter to offer better user experience. The existing schemes use the single source and multisource delivery but are unable to balance between stream quality and network congestion for mobile users. We proposed a Quality Oriented Multimedia Content Delivery Scheme (QOMCDS) for the mobile cloud to deliver better quality multimedia contents for the mobile user. The multimedia contents are delivered to the mobile device based on the device's parameters and network environment. The objective video quality assessment models like Peak Signal-to-Noise Ratio (PSNR), Structural Similarity (SSIM), and Video Quality Measurement (VQM) are used to measure the quality of the video. The client side Quality of Experience metric such as Startup delay, Rebuffering events, and Bitrate switch count was used for evaluation. The proposed scheme is evaluated using dash.js and is compared to existing schemes. The results show significant improvement over existing multimedia content delivery schemes.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.12
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• pp.3257-3274
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• 2012

Broadcast routing has become an important research field for vehicular ad-hoc networks (VANETs) recently. However, the packet delivery rate is generally low in existing VANET broadcast routing protocols. Therefore, the design of an appropriate broadcast protocol based on the features of VANET has become a crucial part of the development of VANET. This paper analyzes the disadvantage of existing broadcast routing protocols in VANETs, and proposes an improved algorithm (namely ODAM-C) based on the ODAM (Optimized Dissemination of Alarm Messages) protocol. The ODAM-C algorithm improves the packet delivery rate by two mechanisms based on the forwarding features of ODAM. The first distance-based mechanism reduces the possibility of packet loss by considering the angles between source nodes, forwarding nodes and receiving nodes. The second mechanism increases the redundancy of forwarding nodes to guarantee the packet success delivery ratio. We show by analysis and simulations that the proposed algorithm can improve packet delivery rate for vehicular networks compared against two widely-used existing protocols.

• Macromolecular Research
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• v.15 no.3
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• pp.195-201
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• 2007

Non-viral vectors, including lipid- or polymer-based systems, have attracted much attention to date as a gene delivery vehicle, due to safety issues with viral vectors. Chitosan, a naturally existing cationic polymer, has shown great potential as a gene delivery carrier, as it has low immunogenicity and toxicity, excellent transcellular transport ability, and is relatively easy to chemically modify. This review summarizes and discusses the general features of chitosan and its applications as a delivery carrier of DNA and RNA.

• Journal of Korean Library and Information Science Society
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• v.29
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• pp.27-63
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• 1998

The purpose of this study is to analyze the document delivery service(DDS) of the academic libraries and suggest its improvement model in Korea. DDS means providing copies of information requests in any format and from any source. And DDS is gaining in importance as libraries turn to 'just-in-time' access rather than 'just-in-case' collection to meet user information needs. By good fortune, rising journal subscription prices, declining financial resources, canceling some of journal subscriptions, electronic transmission technologies, and the rise of commercial document delivery services have allowed libraries to begin to deliver articles to users in a much more rapid and acceptable time frame. Therefore, the library paradigm for the 2000s must be the creation of new document delivery structures which capitalize on the access tolls and structures created by librarians during the past generations. First of all, library-based document service requires a close review of existing library-to-library delivery mechanisms, application of technology to transfer of facsimiles of materials and facilitated use of existing fee-based document sources. The ideal document delivery system would feature a transparent, seamless electronic service incorporating searching and browsing identification and marking of desired items, and transmission and fulfillment of requests. And requested items would be supplied from library collection, commercial suppliers, or other sources. But the future of DDS will succeed when physical resources, policies, personnel, and practices are organized to provide timely information delivery to users.

• Korean Journal of Construction Engineering and Management
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• v.18 no.2
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• pp.3-11
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• 2017

Aging buildings over 15 years reaches about 74% of 177 thousand buildings in Domestic public buildings. Due to the aging building, the energy loss is a serious problem. In order to reduce the energy usage through improving the energy efficiency on the existing buildings, the government & the local autonomous entity conduct the energy efficiency projects through the remodeling, repairing & equipment replacement on the existing buildings. The green remodeling is applied to the existing public buildings in recently revised the act on the creation and support of green building. However, the standard is not obvious that the work scope of green remodeling, financing and project delivery method. This paper propose is to suggest project delivery system for vitalizing the green remodeling. Green remodeling is defined on basis of the occurring work under project life cycle based on the existing building process and the financing method for owners and companies and the project delivery system according to work scope of green remodeling are proposed in this paper

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.375-383
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• 2021

Due to COVID-19, people are building new lifestyles such as online shopping, online travel, and video conferencing by limiting going out and gatherings. Such rapid social change is causing new problems and deepening existing problems at the same time. In particular, as online consumption increases significantly, traffic congestion, air pollution, and the heavy workload of delivery drivers are deepening in the daily logistics industry, and face-to-face delivery is emerging as a new problem. With the advent of the 4th industrial revolution, unmanned delivery using drones, artificial intelligence, and autonomous driving is emerging as an alternative to the existing logistics industry. However, space for logistics facilities and securing additional logistics sites due to drone flight are emerging as new problems to be solved. Therefore, it is intended to link additional services such as logistics movement, storage, and delivery by utilizing the existing transportation business, the subway, as a space for a logistics facility for drones that can solve existing problems and new problems.

• IEMEK Journal of Embedded Systems and Applications
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• v.18 no.5
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• pp.249-257
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• 2023

This paper discusses the increasing need for autonomous delivery robots due to the current growth in the delivery market, rising delivery fees, high costs of hiring delivery personnel, and the need for contactless services. Additionally, the cost of hardware and complex software systems required to build and operate autonomous delivery robots is high. To provide a low-cost alternative to this, this paper proposes a autonomous delivery robot platform using a low-cost sensor combination of 2D LIDAR, depth camera and tracking camera to replace the existing expensive 3D LIDAR. The proposed robot was developed using the RTAB-Map SLAM open source package for 2D mapping and overcomes the limitations of low-cost sensors by using the convex hull algorithm. The paper details the hardware and software configuration of the robot and presents the results of driving experiments. The proposed platform has significant potential for various industries, including the delivery and other industries.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.1
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• pp.105-122
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• 2011

The fundamental design goal of wireless sensor MAC protocols is to minimize unnecessary power consumption of the sensor nodes, because of its stringent resource constraints and ultra-power limitation. In existing MAC protocols in wireless sensor networks (WSNs), duty cycling, in which each node periodically cycles between the active and sleep states, has been introduced to reduce unnecessary energy consumption. Existing MAC schemes, however, use a fixed duty cycling regardless of multi-hop communication and traffic fluctuations. On the other hand, there is a tradeoff between energy efficiency and delay caused by duty cycling mechanism in multi-hop communication and existing MAC approaches only tend to improve energy efficiency with sacrificing data delivery delay. In this paper, we propose two different MAC schemes (ADS-MAC and ELA-MAC) using closed-loop control in order to achieve both energy savings and minimal delay in wireless sensor networks. The two proposed MAC schemes, which are synchronous and asynchronous approaches, respectively, utilize an adaptive timer and a successive preload frame with closed-loop control for adaptive duty cycling. As a result, the analysis and the simulation results show that our schemes outperform existing schemes in terms of energy efficiency and delivery delay.

• Journal of the Korea Safety Management & Science
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• v.24 no.3
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• pp.29-37
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• 2022

The development of technology related to the Fourth Industrial Revolution and the growth of the online market due to pandemic are continuing the growth of the logistics market for product delivery. If it is difficult to deliver the product directly to the customer during delivery, storage and delivery using the unmanned courier box are being carried out. However, existing storage boxes are not actively used due to lack of usability even though they have the advantage of storing goods and delivering non-face-to-face. In addition, existing courier boxes are not prepared for cold chain transportation. The unmanned delivery storage device with ICT cold chain technology should be developed to prepare for the transition to non-face-to-face society, to improve logistics efficiency and meet user's requirements. Also, it is necessary to consider the measures to reduce the safety problems that may occur during the use and maintenance of the automatic system. This study conducted a model-based analysis for the development of unmanned delivery storage devices with ICT cold chain technology, and conducted a study to derive the system development specifications that meet the requirements and secure safety and apply them to the development process.

• The Korean Journal of Franchise Management
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• v.15 no.2
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• pp.39-56
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• 2024

Purpose: Delivery food continues to grow. In the past, restaurant companies directly hired delivery workers to deliver food, but now, restaurant companies use delivery service platform companies to carry out delivery work rather than directly hiring delivery workers. Therefore, this study seeks to determine the impact of delivery food benefits in the restaurant industry on brand image, trust, and word-of-mouth intention. Research design, data, and methodology: To test the hypotheses of this study, 400 questionnaires were distributed and 340 were collected. Among these, 321 questionnaires, excluding 19 questionnaires that were answered insincerely, were used in the final analysis. Result. First, delivery food benefits were found to have a significant impact on brand image and trust. Second, brand image was found to have a significant effect on trust and word-of-mouth intention. Third, trust was found to have a significant effect on word-of-mouth intention. Conclusions: First, existing research focused on studying the attributes of delivery food in the restaurant industry, but this study studied the benefits that consumers can obtain through purchase among these attributes. Second, delivery food restaurants need to design promotions and advertisements in a way that displays coupons, points, or mileage. Third, quick delivery of orders can be a competitive advantage for delivery food restaurants.