Dabin Kim - Academia.edu (original) (raw)

Papers by Dabin Kim

2018 International Conference on Information and Communication Technology Convergence (ICTC)

In this paper, we address the trust management issue in a military IoT networks where nodes are d... more In this paper, we address the trust management issue in a military IoT networks where nodes are deployed in harsh and hostile area and communicates. In particular, due to the limited resources of the node, it is of great importance to detect and isolate malicious nodes in an energy-efficient way. Most previous work adopts proactive scanning method that periodically exchanges control messages and does computation for updating trust values over the network, which may incur a waste of energy when no attack is being launched in the network. Here, we present an stepwise approach trust evaluation method using a tree structured routing, in which 1) the trust evaluation process is triggered by nodes only when they sense a suspicious behavior of their child nodes; 2) The evaluation process consists of two phases: querying to its parent node, and local computation of the trust value; Via simulation study using OPNET simulator, it is proven that compared to the existing work, the proposed scheme could achieve the same level of security with much less energy consumption.

Cell Reports Physical Science, 2022

Effective mitigation technology to prevent the spread of severe acute respiratory syndrome corona... more Effective mitigation technology to prevent the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is required before achieving population immunity through vaccines. Here we demonstrate a virus-blocking textile (VBT) that repulses SARS-CoV-2 by applying repulsive Coulomb force to respiratory particles, powered by human body triboelectric energy harvesting. We show that SARS-CoV-2 has negative charges, and a human body generates high output current of which peak-to-peak value reaches 259.6 μA at most, based on triboelectric effect. Thereby, the human body can sustainably power a VBT to have negative electrical potential, and the VBT highly blocks SARS-CoV-2 by repulsion. In an acrylic chamber study, we found that the VBT blocks SARS-CoV-2 by 99.95%, and SARS-CoV-2 in the VBT is 13-fold reduced. Our work provides technology that may prevent the spread of virus based on repulsive Coulomb force and triboelectric energy harvesting.

IEEE Robotics and Automation Letters, 2022

This paper presents a new online multi-agent trajectory planning algorithm that guarantees to gen... more This paper presents a new online multi-agent trajectory planning algorithm that guarantees to generate safe, dynamically feasible trajectories in a cluttered environment. The proposed algorithm utilizes a linear safe corridor (LSC) to formulate the distributed trajectory optimization problem with only feasible constraints, so it does not resort to slack variables or soft constraints to avoid optimization failure. Also, we adopt a priority-based goal planning method to prevent the deadlock without additional communication for decision making. The proposed algorithm can compute the trajectories for 60 agents on average 15.5 ms per agent with an Intel i7 laptop and can find the trajectory that reaches the goal without deadlock in both random forest and indoor space. We validated safety and operability of the proposed algorithm through a real flight test with ten quadrotors in a maze-like environment.

International Journal of Food Microbiology, 2021

Bacillus cereus, a foodborne pathogen, is capable of forming spores and biofilms as methods to wi... more Bacillus cereus, a foodborne pathogen, is capable of forming spores and biofilms as methods to withstand environmental stresses. These bacterial structures are an issue for food safety as they aid the bacteria survive heat sterilisation processes of foods and food contact surfaces. This study was conducted to investigate the role of the biofilm structure in providing an extra layer of protection to spores against heat treatments. For this, heat resistance of B. cereus spores in intact biofilms was compared to that of planktonic spores in vitro and in a Cheonggukjang jjigae food model. Using methods developed in this study to measure the wet and dry heat resistance of spores in intact biofilms, it was found that B. cereus spores have significantly higher heat resistances when present in biofilms rather than as planktonic spores, and that dry heat is less effective than wet heat at killing spores in biofilms. In further detail, for wet heat treatments, spores in biofilms of the strain isolated from Cheonggukjang (Korean fermented whole soybean), B. cereus CH3, had generally higher wet heat resistances than the reference strain, B. cereus ATCC 10987, both in vitro and in the Cheonggukjang jjigae food model. However, the spores in biofilms of the two strains showed similar heat resistance to dry heat, with some exceptions, when biofilms were formed in vitro or in Cheonggukjang jjigae broth. Meanwhile, B. cereus ATCC 10987 spores in biofilms had higher or similar wet heat resistances in vitro compared to in Cheonggukjang jjigae broth. Wet heat resistances of B. cereus CH3 spores in biofilms were all statistically similar regardless of biofilm formation media (brain heart infusion and Cheonggukjang jjigae broths). For dry heat, spores in biofilms of both B. cereus strains were more heat resistant when biofilms were formed in the Cheonggukjang jjigae food model rather than in vitro. Altogether, heat resistances of spores in biofilms formed in vitro and in the food environment were found to be different depending on the tested B. cereus strain, but higher than planktonic spores in any case. This is the first study examining the heat resistance of B. cereus spores in intact biofilms matrices attached to the surface, both in vitro and in a food model. Therefore, this research is valuable to understand the protective effects of biofilms formed in food environments and to reduce the food safety risks associated with B. cereus.

2021 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2021

Visual navigation has been widely used for state estimation of micro aerial vehicles (MAVs). For ... more Visual navigation has been widely used for state estimation of micro aerial vehicles (MAVs). For stable visual navigation, MAVs should generate perception-aware paths which guarantee enough visible landmarks. Many previous works on perception-aware path planning focused on samplingbased planners. However, they may suffer from sample inefficiency, which leads to computational burden for finding a global optimal path. To address this issue, we suggest a perceptionaware path planner which utilizes topological information of environments. Since the topological class of a path and visible landmarks during traveling the path are closely related, the proposed algorithm checks distinctive topological classes to choose the class with abundant visual information. Topological graph is extracted from the generalized Voronoi diagram of the environment and initial paths with different topological classes are found. To evaluate the perception quality of the classes, we divide the initial path into discrete segments where the points in each segment share similar visual information. The optimal class with high perception quality is selected, and a graphbased planner is utilized to generate path within the class. With simulations and real-world experiments, we confirmed that the proposed method could guarantee accurate visual navigation compared with the perception-agnostic method while showing improved computational efficiency than the samplingbased perception-aware planner.

2020 IEEE International Conference on Robotics and Automation (ICRA), 2020

Existing studies for environment interaction with an aerial robot have been focused on interactio... more Existing studies for environment interaction with an aerial robot have been focused on interaction with static surroundings. However, to fully explore the concept of an aerial manipulation, interaction with moving structures should also be considered. In this paper, a multirotor-based aerial manipulator opening a daily-life moving structure, a hinged door, is presented. In order to address the constrained motion of the structure and to avoid collisions during operation, model predictive control (MPC) is applied to the derived coupled system dynamics between the aerial manipulator and the door involving state constraints. By implementing a constrained version of differential dynamic programming (DDP), MPC can generate position setpoints to the disturbance observer (DOB)based robust controller in real-time, which is validated by our experimental results.

Frontiers in Microbiology, 2021

Bacterial spores often survive thermal processing used in the food industry, while heat treatment... more Bacterial spores often survive thermal processing used in the food industry, while heat treatment leads not only to a decrease in the nutritional and organoleptic properties of foods, but also to a delay in fermentation of fermented foods. Selective reduction of undesirable spores without such impediments is an ongoing challenge for food scientists. Thus, increased knowledge of the spore-forming bacteria is required to control them. In this study, the heat resistance results (D100°C) of the spores of four Bacillus species were determined and compared to previous literature, and found that B. cereus has significantly lower heat resistance than the other Bacillus species, B. coagulans, B. subtilis, and B. licheniformis. Using the spores of these strains, this study also evaluated the effects of single and combined supplementation of calcium (0.00–2.00 mM) and manganese (0.00–0.50 mM) on heat resistance (D100°C). The results revealed that the spores of B. licheniformis and B. cereus di...

IEEE/ASME Transactions on Mechatronics, 2021

This article introduces a fully actuated multirotor flight system utilizing the tilting-thruster-... more This article introduces a fully actuated multirotor flight system utilizing the tilting-thruster-type multirotor (<inline-formula><tex-math notation="LaTeX">$T^3$</tex-math></inline-formula>-multirotor), a new type of multirotor platform that enables six-controllable-degree-of-freedom flight with minimal structural heterogeneity compared to conventional multirotor designs. This new multirotor platform consists of upper and lower parts (or thruster and fuselage parts), with a unique kinematic structure and dedicated servomechanism that controls the relative attitude between the two parts. With the new mechanism, the fuselage of the <inline-formula><tex-math notation="LaTeX">$T^3$</tex-math></inline-formula>-multirotor can control the translational and rotational motions independently of each other, allowing six-degree-of-freedom motion that was not possible with conventional multirotors. A dedicated robust control algorithm is developed based on a thorough analysis of system dynamics to derive accurate six-degree-of-freedom motion of the platform. The flight control performance of the platform is validated through simulations and actual experiments. Several flight tasks are also performed to demonstrate the potential of the <inline-formula><tex-math notation="LaTeX">$T^3$</tex-math></inline-formula>-multirotor in overcoming the limitations of conventional multirotors.

Talanta, 2020

In this paper, we developed a non-equilibrium rapid replacement aptamer (NERRA) assay that perfor... more In this paper, we developed a non-equilibrium rapid replacement aptamer (NERRA) assay that performed ultrafast (in 30 s) quantitative detection of phthalic acid esters (PAEs) without waiting for the reaction to reach equilibrium. NERRA assay employed fluorescence PoPo3 dye intercalated in an ssDNA aptamer to selectively detect and quantify the PAEs in water. As the intercalated dye was replaced by the PAEs and quenched in the water, the rate of fluorescence change became proportional to PAEs concentration. The sensitivity of NERRA assay was first evaluated with a commercial spectrofluorometer. The selectivity for PAE mixture, individual PAEs, and non-phthalate compounds were also investigated. NERRA assay was also able to quantitatively detect the PAEs in a common plastic product (picnic mat), and the results were compared with those of gas chromatography mass spectrometry. Finally, a custom analyzer (8.5 cm × 8.5 cm × 16.5 cm) was built to demonstrate the portability of the NERRA assay. Using a commercial spectrofluorometer, NERRA assay was able to quantitatively detect a PAE mixture in 30 min with an LOQ of 0.1 μg/L. Using the portable custom analyzer, the detection time was shortened to 30 s with a tradeoff in the LOQ (1 μg/L). In both cases, the LOQs remain within the environmentally relevant PAE concentrations of 0.1-1472 μg/L.

IEEE Access, 2018

In tactical mobile ad hoc networks, unmanned vehicles such as ground maneuvering nodes or aircraf... more In tactical mobile ad hoc networks, unmanned vehicles such as ground maneuvering nodes or aircraft, are increasingly expected to be exploited for information collection in battlefields or dangerous areas on behalf of soldiers in consideration of their safety. The primary function of this networking system is to conduct military surveillance and reconnaissance through unmanned vehicles, which are teleoperated via a central node by sending command messages in real time. This requires simultaneous network traffic flow in both directions, i.e., uplink and downlink, both of which need to occur in real time with high reliability. In this paper, we propose a novel centralized time-division multiple access (TDMA) protocol to guarantee network reliability and quality of service regarding the bidirectional traffic. We develop a bidirectional-pipelined TDMA (BiPi-TMAC) protocol that consists of three parts: a slot-requesting procedure with bandwidth requirement, a depth-based pipelined slot allocation algorithm, and multiple MAC queue management for prioritized packet scheduling. We implement and evaluate the proposed scheme through the ns-3 simulator and show that it improves performance in terms of both uplink and downlink traffic. INDEX TERMS Ad hoc networks, military communication, quality of service, real-time communication, time division multiple access, reliability, unmanned vehicles.

The Journal of Korean Island, 2020

The Journal of Korean Institute of Communications and Information Sciences, 2018

Journal of Korea Society of Waste Management, 2016

The ocular surface, Jan 5, 2018

To investigate the influence of blinking on tear film parameters, ocular surface characteristics,... more To investigate the influence of blinking on tear film parameters, ocular surface characteristics, and dry eye symptomology. A total of 154 participants were recruited in an age, gender and ethnicity-matched cross-sectional study, of which 77 exhibited clinically detectable incomplete blinking, and 77 did not. Blink rate, dry eye symptomology, tear film parameters, and ocular surface characteristics were assessed in a single clinical session. Overall, a higher proportion of participants exhibiting incomplete blinking fulfilled the TFOS DEWS II dry eye diagnostic criteria (64% versus 44%, p = 0.02), with an odds ratio (95% CI) of 2.2 (1.2-4.2) times. Participants exhibiting incomplete blinking had higher Ocular Surface Disease Index scores (18 ± 13 versus 12 ± 9, p = 0.01), and greater levels of meibomian gland dropout (41.3 ± 15.7% versus 27.5 ± 14.1%, p < 0.001). Furthermore, poorer tear film lipid layer thickness, non-invasive tear film stability, expressed meibum quality, eyeli...

China Communications, 2016

The phenomenon of data explosion represents a severe challenge for the upcoming big data era. How... more The phenomenon of data explosion represents a severe challenge for the upcoming big data era. However, the current Internet architecture is insufficient for dealing with a huge amount of traffic owing to an increase in redundant content transmission and the end-point-based communication model. Information-centric networking (ICN) is a paradigm for the future Internet that can be utilized to resolve the data explosion problem. In this paper, we focus on content-centric networking (CCN), one of the key candidate ICN architectures. CCN has been studied in various network environments with the aim of relieving network and server burden, especially in name-based forwarding and in-network caching functionalities. This paper studies the effect of several caching strategies in the CCN domain from the perspective of network and server overhead. Thus, we comprehensively analyze the in-network caching performance of CCN under several popular cache replication methods (i.e., cache placement). We evaluate the performance with respect to well-known Internet traffic patterns that follow certain probabilistic distributions, such as the Zipf/Mandelbrot-Zipf distributions, and flash-crowds. For the experiments, we developed an OPNET-based CCN simulator with a realistic Internet-like topology.

2016 International Conference on High Performance Computing & Simulation (HPCS), 2016

Named data networking (NDN) is a newly proposed networking architecture, which a few network scie... more Named data networking (NDN) is a newly proposed networking architecture, which a few network scientists believe that it is an appropriate protocol to distribute Big Data files in the network of supercomputing domain. This new scheme is organized to reduce high network congestion resulted from it. In addition to many current NDN applications, such as climate modeling data service, another supercomputing domain, its repository applications also have been developed. However, compared to the ordinary file systems, they now significantly underperform in writing operations. It will be highly likely to prevent scientists and engineers from applying NDN over their networks because it could turn to be as a system bottleneck in the performance critical area. In this paper, writing operations of those repositories will be examined and how performance can differ according to the software architectures placed in them. Finally, we will discuss optimization schemes to make it perform better in a large scaled computing system.

Journal of the American Chemical Society, 2016

Pages 5352−5253. The conditions for detection in vitro should be corrected owing to the instrumen... more Pages 5352−5253. The conditions for detection in vitro should be corrected owing to the instrument failure. 1 All measurements of probes (5 μM) were performed with amino acids (500 μM) in PBS buffer solution (10 mM, pH 7.36) containing 0.5% DMSO (λ ex = 635 nm, λ em = 785 nm, slit: 10/10 nm). Figure 2, shown here, reflects those corrections, and the Supporting Information has also been

Proceedings of the 9th International Conference on Ubiquitous Information Management and Communication, 2015

The Content Centric Networking (CCN) architecture has been designed to resolve a traffic explosio... more The Content Centric Networking (CCN) architecture has been designed to resolve a traffic explosion problem of the traditional IP-based Internet by making a name-based content retrieving and in-network caching. Many effective methods have been discussed with various networking technologies to save substantial bandwidth usages in a CCN. However, still it can induce a so-called "message storming problem" because it often fails to retrieve contents with unexpected message loss, followed by a fallback scheme activation that results in a huge number of content request message flooding over the whole network. Such a message storming problem even becomes severe when the concept of CCN is applied in wireless multi-hop networking environments. In this paper, we present a lightweight name-based content retrieving algorithm for a multi-hop wireless CCN based on a three-tier strategy that consists of a periodic forwarder information updating, an eligible forwarder selection, and a reliable CCN message broadcasting strategy methods. We have implemented the proposed scheme over the CCNx testbed and conducted a comprehensive evaluation study, by which its superior performance with more than 50% higher throughput is proven compared to the basic opportunistic broadcasting method of CCN.