Liquid-based memory and artificial synapse

Kim, Dongshin,Lee, Jang-Sik The Royal Society of Chemistry 2019 Nanoscale Vol.11 No.19

<P>The brain is considered as the most efficient computational system, and broadly consists of neurons and synapses. Synapses are spaces between neurons; neurotransmitters move from pre-synaptic neurons to post-synaptic neurons to transfer signals. Active research has been carried out to mimic the functions of the human nervous system using solid materials. However, mimicking the exact functions of human synaptic behaviors using solid-state materials is limited because the movement of neurotransmitters in liquid (real synapses) and solid (artificial synapses) environments is very different. Here, we demonstrate synaptic properties including long-term memory, paired-pulse facilitation, and excitatory post-synaptic current, resembling the properties of neurons in biological systems in a liquid-based resistive-switching memory (LRSM) device with a two-terminal structure designed to function based on silver nitrate (AgNO3) solution. The LRSM device can be utilized in very versatile forms and be fabricated in any shapes since its main component is liquid.</P>

The Application of Inclusive Management to Collaboration among Organizations in Emergency Management

Dongshin Kim 한국공공관리학회 2012 한국공공관리학보 Vol.26 No.3

Addressing emergency, such as natural and artificial disaster, is an important duty of public administration. Many articles state the importance of effective collaboration to deal with emergency. However, the effective collaboration among agencies and members to deal with emergency is not easy in reality. Therefore, it is meaningful to ask next questions. How can the effective collaboration to address urgent situations happen? What elements or aspects are required for effective collaboration? For the purpose of the study, the paper examines the applicability of inclusive management to the effective collaboration among organizations to deal with emergency. It is a case study. The 9/11 Arlington county case in 2001 (terrorist attack on Pentagon) was selected to examine the roles of inclusive management in collaboration. The paper used interviews and documentary survey to make a deep investigation of the processes of emergency preparedness. The results show that relational, informational, and operational aspects affect effective collaboration among organizations to address emergency. By finding that relational and informational works help the inclusion of organizations for common goals, which affects effective collaboration among organizations, the paper provides the evidence of the applicability of inclusive management to organizational collaboration in emergency management.

A New Quadtree Data Structure for Mobile Robot Mapping Problem in a Large Scale Area

Dongshin Kim,Taewon Han 제어로봇시스템학회 2013 제어로봇시스템학회 국내학술대회 논문집 Vol.2013 No.5

On-Line Initialization and Extrinsic Calibration of an Inertial Navigation System With a Relative Preintegration Method on Manifold

Kim, Dongshin,Shin, Seunghak,Kweon, In So IEEE 2018 IEEE transactions on automation science and engine Vol.15 No.3

<P>Inertial measurement units (IMUs) are successfully utilized to compensate localization errors in sensor fused inertial navigation systems. An IMU generally produces high-frequency signals ranging from 100 to 1000 Hz, and preintegration methods are applied to effectively process these high-frequency signals for inertial navigation systems. The main problem with an existing preintegration method is that the inertial propagation models in the method are only generated at the IMU’s coordinate system. Hence, the models have to be converted to the coordinate system of the other sensor in order to apply its constraint. So, the iterative optimization framework using the conventional method takes large amount of time. In addition, since a general rigid body transformation cannot transfer a velocity propagation model to the other coordinate system, the concept of relative motion analysis needs to be considered. To solve the problems above, in this paper, we propose a novel relative preintegration (RP) method that can generate inertial propagation models at any sensor’s coordinate system in a rigid body. This permits accurate and fast IMU processing in sensor fused inertial navigation systems. We applied new nonlinear optimization frameworks to solve initialization and extrinsic calibration problems for the IMU–IMU, IMU–Camera, and IMU–LiDAR pair based on the proposed RP method in an on-line manner, and the superior results of the mentioned processes are presented as well. <I>Note to Practitioners</I>—In the proposed method, extrinsic calibration parameters can be estimated during the localization process without any initial manual precalibration procedure. Besides, an IMU is small and inexpensive, so small AGVs in warehouses, or mobile manipulators in factories are good applications for the proposed method, where they require a certain level of localization accuracy. The localization module using the proposed method can be mounted anywhere in a robot without restrictions. The initialization procedure has been executed for a few seconds with arbitrary movement in the field of view of the first frame, then the initial gravity and velocity vector, and extrinsic parameters, which are estimated during the initialization phase, are applied to a general SLAM problem.</P>

Organizational Culture and Interagency Collaboration

Dongshin Kim 한국공공관리학회 2010 한국공공관리학보 Vol.24 No.4

A state of emergency needs collaboration among government agencies. Regarding the response to emergency, collaboration among agencies has become important in the public sector. However, despite the necessity and the importance of collaboration in dealing with emergency, it is hard to produce successful collaboration among government agencies. Why is it hard to achieve effective interagency collaboration in emergency? And what do we miss to understand interagency collaboration in emergency? The paper addresses these questions from the perspective of organizational culture. The collaboration case between the New York City Police Department (NYPD) and the New York City Fire Department (FDNY) in response to 9/11 emergency in New York City is used to analyze the effects of each organizational culture on interagency collaboration. The analysis of the two organizations by organizational culture shows that NYPD has a more procedure-based organizational culture and FDNY has a more result-based organizational culture. The members of NYPD and FDNY made their decisions and activities responding to 9/11 emergency on the basis of each of organizational culture, which produces collaboration problems. The results of the study indicate that organizational culture should be considered and more diverse studies of organizational culture for effective interagency collaboration in emergency are needed.

만도 MGH VDC 시스템 개발

김동신(Dongshin Kim),김차환(Chahwan Kim),현준진(Junjin Hyon),신현성(Hyonsung Shin),박병석(Byungsuk Park) 한국자동차공학회 1999 한국자동차공학회 학술강연 논문집 Vol.1999 No.9

Synthesis of metallic ReO3 nanowires

Myung, Dongshin,Lee, Yumin,Lee, Jaeyeon,Yu, Hak Ki,Lee, Jong-Lam,Baik, Jeong Min,Kim, Woong,Kim, Myung Hwa Wiley (John WileySons) 2010 Physica status solidi. PSS-RRL. Rapid Research Let Vol.4 No.12

다중 방송 메쉬 상에서 최근접쌍을 구하는 최적 병렬 알고리즘

김동신(Dongshin Kim),유관우(Kwanwoo Ryu) 한국정보과학회 1998 정보과학회논문지 : 시스템 및 이론 Vol.25 No.10

평면상의 n개의 점들의 집합 S={q₁, q₂, . . . , q_n}가 주어질 때, 이들 n개의 점들중 서로간의 거리가 가장 가까운 두점을 최근접쌍(the closest pair)이라 한다. 본 논문에서는 n×n 다중방송메쉬(Mesh with Multiple Broadcasting, MMB) 상에서 최근접쌍을 찾는 최적 시간 병렬 알고리즘을 제시한다. [9]에서는 이 문제보다 더 일반적인 문제인 각각의 점에서 가장 가까운 점들을 찾는 ANN(All-Nearest-Neighbor) 문제를 해결하는 알고리즘이 제시되어 있는데, 이는 아주 복잡한 알고리즘이며, 또 [9]에서는 이 보다 더 쉬운 방법으로 최근접쌍을 찾을 수 없었다고 한다. 본 논문에서는 이 최근접쌍을 찾는 문제를 해결하는 보다 더 간단한 최적 알고리즘을 제시한다. The Closest Pair problem can be defined as follows: Given a set S={q₁, q₂, . . . , q_n} of n points in the plane, find a pair of points in S that are closest to each other. In this paper we develop a time-optimal parallel algorithm for solving the CP problem on the n×n mesh with multiple broadcasting(MMB). An optimal algorithm to solve a more general problem of finding a nearest neighbor for every given point in the MMB has been already presented in [9]. However, this algorithm is very complicated, and in [9] they said that they could not construct a simpler algorithm for solving the closest pair problem. Hence, we present in this paper a much simpler algorithm for finding a closest pair among the given n points in the plane.

HOUSING MARKET INFORMATION EFFICIENCY

( Donn Dongshin Kim ),( Youngme Seo ) 한국부동산분석학회 2023 부동산분석학회 학술발표논문집 Vol.2023 No.0

Optimized transmission power control of interrogators for collision arbitration in UHF RFID systems

Joongheon Kim,Wonjun Lee,Eunkyo Kim,Dongshin Kim,Kyoungwon Suh IEEE 2007 IEEE communications letters Vol.11 No.1

<P>The emergence of UHF RFID as one of the dominant technology trends has posed numerous unique challenges to researchers. This letter presents a novel, theoretically-grounded collision arbitration protocol, called TPC-CA, which optimally controls transmission power of RFID interrogators and thereby reducing redundant interrogator collisions</P>