• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.4
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• pp.87-97
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• 2009

A Mobile Ad hoc Network (MANET) is characterized by multi-hop wireless connectivity, frequently changing network topology with mobile nodes and the efficiency of the dynamic routing protocol plays an important role in the performance of the network. In this paper, the performance of five routing protocols for MANET is compared by using OPNET modeler: AODV, DSR, GRP, OLSR and TORA. The various performance metrics are examined, such as packet delivery ratio, end-to-end delay and routing overhead with varying data traffic, number of nodes and mobility. In our simulation results, OLSR shows the best performance in terms of data delivery ratio in static networks, while AODV has the best performance in mobile networks with moderate data traffic. When comparing proactive protocols (OLSR, GRP) and reactive protocols (AODV, DSR) with varying data traffic in the static networks, proactive protocols consistently presents almost constant overhead while the reactive protocols show a sharp increase to some extent. When comparing each of proactive protocols in static and mobile networks, OLSR is better than GRP in the delivery ratio while overhead is more. As for reactive protocols, DSR outperforms AODV under the moderate data traffic in static networks because it exploits caching aggressively and maintains multiple routes per destination. However, this advantage turns into disadvantage in high mobility networks since the chance of the cached routes becoming stale increases.

• Journal of Pharmaceutical Investigation
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• v.40 no.spc
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• pp.33-43
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• 2010

Hyaluronic acid (HA) is a biodegradable, biocompatible, non-toxic, non-immunogenic and non-inflammatory linear polysaccharide, which has been used for various medical applications including arthritis treatment, wound healing, ocular surgery, and tissue augmentation. Because of its mucoadhesive property and safety, HA has received much attention as a tool for drug delivery system development. It has been used as a drug delivery carrier in both nonparenteral and parenteral routes. The nonparenteral application includes the ocular and nasal delivery systems. On the other hand, its use in parenteral systems has been considered important as in the case of sustained release formulation of protein drugs through subcutaneous injection. Particles and hydrogels by various methods using HA and HA derivatives as well as by conjugation with other polymer have been the focus of many studies. Furthermore, the affinity of HA to the CD44 receptor which is overexpressed in various tumor cells makes HA an important means of cancer targeted drug delivery. Current trends and development of HA as a tool for drug delivery will be outlined in this review.

• IE interfaces
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• v.13 no.3
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• pp.455-461
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• 2000

Logistics systems can be evaluated by how productively distribution center operates, how promptly transportation vehicle dispatches, how efficiently facility layout is, and so on. In this paper, a practical vehicle routing scheme with fixed delivery time and fixed vehicle routes is introduced. The method helps the distribution center reduce logistics cost with respect to dispatching vehicles, and satisfy the customer with pre-determined delivery time window constraints. A case study has shown that the proposed scheme not only generates a feasible schedule with time windows, but also balances material flow in warehouse.

• Industrial Engineering and Management Systems
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• v.10 no.1
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• pp.24-33
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• 2011

In this paper, we consider the Location-Routing Problem with simultaneous pickup and delivery (LRPSPD) which is a general case of the location-routing problem. The LRPSPD is defined as finding locations of the depots and designing vehicle routes in such a way that pickup and delivery demands of each customer must be performed with same vehicle and the overall cost is minimized. Since the LRPSPD is an NP-hard problem, we propose a hybrid heuristic approach based on genetic algorithms (GA) and simulated annealing (SA) to solve the problem. To evaluate the performance of the proposed approach, we conduct an experimental study and compare its results with those obtained by a branch-and-cut algorithm on a set of instances derived from the literature. Computational results indicate that the proposed hybrid algorithm is able to find optimal or very good quality solutions in a reasonable computation time.

• Journal of Pharmaceutical Investigation
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• v.38 no.6
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• pp.429-432
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• 2008

Drug delivery systems (DDS) have entered mainstream in the pharmaceutical industry in the recent years. Major pharmaceutical companies as well as small or medium-sized biotechnology companies are developing various DDS-based products. We have established Drug Delivery System Company Database, which is an online searchable database of companies that develop DDS-based products and technologies or supply formulations and/or materials. Company summary, products and key technologies are listed in the database. DDS technology fields also include administration routes and indications of drugs. DDS terminologies, Statistical analysis, Useful Links, Glossary and Comments pages are also provided.

• Journal of Information Processing Systems
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• v.13 no.6
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• pp.1544-1553
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• 2017

The network coding mechanism has attracted much attention because of its advantage of enhanced network throughput which is a desirable characteristic especially in a multi-hop wireless network with limited link capacity such as the device-to-device (D2D) communication network of 5G. COPE proposes to use the XOR-based network coding in the two-hop wireless network topology. For multi-hop wireless networks, the Distributed Coding-Aware Routing (DCAR) mechanism was proposed, in which the coding conditions for two flows intersecting at an intermediate node are defined and the routing metric to improve the coding opportunity by preferring those routes with longer queues is designed. Because the routes with longer queues may increase the delay, DCAR is inefficient in delivering real-time multimedia traffic flows. In this paper, we propose a network coding-aware routing protocol for multi-hop wireless networks that enhances DCAR by considering traffic load distribution and link quality. From this, we can achieve higher network throughput and lower end-to-end delay at the same time for the proper delivery of time-sensitive data flow. The Qualnet-based simulation results show that our proposed scheme outperforms DCAR in terms of throughput and delay.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.6
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• pp.25-34
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• 2011

In this paper, In this paper, we propose a Cooperative Routing Protocol (CooRP) for supporting network convergence and transmission services efficiently in mobile ad-hoc wireless sensor networks with Rayleigh fading environments. The main contributions and features of this paper are as follows. First, the routing routes are decided on route stability based on entropy concepts using mobility of nodes within the direction guided line region to increase the operational lifetime of routes as well as reduce control overhead for route construction. Second, a cooperative data transmission strategy based on the constructed stable routing route is used to increase packet delivery ratio with advanced SNR. Third, a theoretical analysis for cooperative data transmission of the proposed CooRP with outage probability is presented. The performance evaluation of the proposed CooRP is performed via simulation using OPNET and analysis. The results of performance evaluation show that the proposed CooRP by using stable routing routes and cooperative transmission can increase packet delivery ratio efficiently.

• Journal of Korean Institute of Industrial Engineers
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• v.35 no.2
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• pp.160-170
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• 2009

This paper studies a vehicle routing problem variant which considers customers to require simultaneous delivery and pick-up under time windows(VRPSDP-TW). The objective of this paper is to minimize the total travel distance of routes that satisfy both the delivery and pick-up demand. We propose a heuristic algorithm for solving the VRPSDP-TW, based on the ant colony system(ACS). In route construction, an insertion algorithm based ACS is applied and the interim solution is improved by local search. Through iterative processes, the heuristic algorithm drives the best solution. Experiments are implemented to evaluate a performance of the algorithm on some test instances from literature.

• Journal of Pharmaceutical Investigation
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• v.41 no.6
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• pp.347-354
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• 2011

Repeated oral administration of loxoprofen can induce many side effects such as gastric disturbances and acidosis. Therefore, we considered alternative routes of administration for loxoprofen to avoid such adverse effects. The aim of this study was to develop an ethylene-vinyl acetate (EVA) matrix system containing a permeation enhancer for enhanced transdermal delivery of loxoprofen. The EVA matrix containing loxoprofen was fabricated and the effects of drug concentration, temperature, enhancer and plasticizer on drug release were studied from the loxoprofen-EVA matrix. The solubility of loxoprofen was highest at 40% (v/v) PEG 400. The release rate of drug from drug-EVA matrix increased with increased loading dose and temperature. The release rate was proportional to the square root of loading dose. The activation energy (Ea), which was measured from the slope of log P versus 1000/T, was 5.67 kcal/mol for a 2.0% loaded drug dose from the EVA matrix. Among the plasticizer used, diethyl phthalate showed the highest release rate of loxoprofen. Among the enhancers used, polyoxyethylene 2-oleyl ether showed the greatest enhancing effect. In conclusion, for the enhanced controlled transdermal delivery of loxoprofen, the application of the EVA matrix containing plasticizer and penetration enhancer could be useful in the development of a controlled drug delivery system.

• Journal of the Korea Institute of Military Science and Technology
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• v.25 no.4
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• pp.425-433
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• 2022

This paper studies the method of delivering munitions using both drones and UGVs that are developing along with the 4th Industrial Revolution. While drones are more mobile than UGVs, their loading capacity is small, and UGVs have relatively less mobility than drones, but their loading capacity is better. Therefore, by simultaneously operating these two delivery means, each other's shortcomings may be compensated. In addition, on actual battlefields, time constraints are an important factor in delivering munitions. Therefore, assuming an actual battlefield environment with a time limit, we establish delivery routes that minimize delivery time by operating both drones and UGVs with different capacities and speeds. If the delivery is not completed within the time limit, penalties are imposed. We devised the hybrid genetic algorithm to find solutions to the proposed model, and as results of the experiment, we showed the algorithm we presented solved the actual size problems in a short time.