• 융합보안논문지
• /
• 제22권5호
• /
• pp.11-20
• /
• 2022

인터넷과 웹 기술이 모바일 장치 중심으로 발전하면서 이미지 데이터는 사람, 텍스트, 공간 등 다양한 유형의 민감정보를 담고 있다. 이러한 특성과 더불어 SNS 사용이 증가하면서 온라인 상의 개인정보가 노출되고 악용되는 피해 규모가 커지고 있다. 그러나 개인정보보호를 위한 다중 유형 객체 탐지 기반의 비식별화 기술에 관한 연구는 미흡한 상황이다. 이에 본 논문은 기존의 단일 유형 객체 탐지 모델을 병렬적으로 이용하여 다중 유형의 객체를 탐지 및 비식별화하는 인공지능 모델을 제안한다. Cutmix 기법을 통해 사람과 텍스트 객체가 함께 존재하는 이미지를 생성하여 학습 데이터로 구성하고, 사람과 텍스트라는 다른 특징을 가진 객체에 대한 탐지 및 비식별화를 수행하였다. 제안하는 모델은 두 가지 객체가 동시에 존재할 때 0.724의 precision과 0.745의 mAP@.5 를 달성한다. 또한, 비식별화 수행 후 전체 객체에 대해 mAP@.5 가 0.224로, 0.4 이상의 감소폭을 보였다.

• 한국물환경학회지
• /
• 제20권5호
• /
• pp.397-408
• /
• 2004

Due to the growing impact of non-point source pollution and limitation of water treatment technology, a new policy of water quality management, called a source protection, is now becoming more important in drinking water supply. The source protection means that the public agency purchases the pollution sensitive area, such as riparian zone, and prohibit locations of point and non-point sources. Many studies have reported that this new policy is more economical in drinking water supply than the conventional one. However, it is very difficult to determine location and size of the pollution sensitive zone in the watershed. In this paper, we presented the scientific criteria for the priority of the pollution sensitive zone, along with a case study of the upstream watershed of the Paldang Reservoir, Han River. This study includes applications of the analytical hierarchy process(AHP) and a watershed-based land prioritization(WLP) model. After major criteria affecting water quality were selected, the AHP and geographic analysis were performed. The WLP model allowed us to include both quantity and quality criteria, using AHP as the multi-criteria method in making decision and reflecting local characteristics and various needs. By adding a travel-time function, which represents the prototype effectively, the results secured adaptability and scientific objectivity as well. As such, the WLP model appeared to provide reasonable criteria in determining the prioritization of land acquisition. If the tested data are used with a validated travel-time and AHP method is applied after further discussion among experts in such field, highly reliable results can be obtained.

• Journal of Electrical Engineering and information Science
• /
• 제2권3호
• /
• pp.105-112
• /
• 1997

The performance of a shared memory multiprocessor system is very sensitive to process scheduling. w can enhance the performance of a whole system as well as of an individual process by taking the multiprocessor characteristics into account in the design of the process scheduler. In this paper, we proposed a general purpose scheduler for a shared memory multiprocessor, called the Two-Level Multi-Scan (TLMS) process scheduler, that considers the processor affinity loosely and decreases the interference among multiple processors greatly. The TLMS scheduler is composed of a local scheduler at each processor and a semi-global scheduler that balances the load among processors. In particular, the semi-global scheduler tries to minimize priority inversion, which is an important factor of the system performance. The TLMS scheduler also tries to reduce the number of resources to be shared and improves the processor utilization. to meet these requirements, th semi-global scheduler interacts with the operation of the local scheduler when a need arises, thus the name is loose processor-affinity. We also show that the proposed scheduling technique can be extended for other types of resources making it a general purpose resource management queue.

• Smart Structures and Systems
• /
• 제12권3_4호
• /
• pp.345-361
• /
• 2013

Locating and assessing the severity of damage in large or complex structures is one of the most challenging problems in the field of civil engineering. Considering that the wavelet packet transform (WPT) has the ability to clearly reflect the damage characteristics of structural response signals and the artificial neural network (ANN) is capable of learning in an unsupervised manner and of forming new classes when the structural exhibits change, this paper investigates a multi-stage structural damage diagnosis method by using the WPT and ANN based on "energy-damage" theory, in which, the wavelet packet component energies are first extracted to be damage sensitive feature and then adopted as input into an improved back propagation (BP) neural network model for damage diagnosis in a step by step mode. To validate the efficacy of the presented approach of the damage diagnosis, the benchmark structure of the American Society of Civil Engineers (ASCE) is employed in the case study. The results of damage diagnosis indicate that the method herein is computationally efficient and is able to detect the existence of different damage patterns in the simulated experiment where minor, moderate and severe damages corresponds to involving in the loss of stiffness on braces or the removal bracing in various combinations.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제15권8호
• /
• pp.2923-2943
• /
• 2021

The double helix structure of DNA makes it diverse, stable and can store information with high density, and these characteristics are consistent with the requirements of molecular communication for transport carriers. In this paper, a specific structure of molecular communication system based on DNA length coding is proposed. Transmitter (Tx) adopts the multi-layer golden foil design to control the release of DNA molecules of different lengths accurately, and receiver (Rx) adopts an effective and sensitive design of nanopore, and the biological information can be converted to the electric signal at Rx. The effect of some key factors, e.g., the length of time slot, transmission distance, the number of releasing molecules, the priori probability, on channel capacity is demonstrated exhaustively. Moreover, we also compare the transmission capacity of DNA-based molecular communication (DNA-MC) system and concentration-based molecular communication (MC) system under the same parameter setting, and the peak value of capacity of DNA-MC system can achieve 0.08 bps, while the capacity of MC system remains 0.025 bps. The simulation results show that DNA-MC system has obvious advantages over MC system in saving molecular resources and improving transmission stability.

• International Journal of Aeronautical and Space Sciences
• /
• 제17권3호
• /
• pp.324-331
• /
• 2016

The present study focuses on the characteristics of a supersonic jet flowing from a rectangular nozzle exit on a flat plate. Flow visualization techniques using schlieren and kerosene-lampblack tracing are utilized to investigate shock reflection structures and boundary-layer separations over a flat plate. Wall pressure measurements are also carried out to quantitatively analyze the flow structures. All observations are repeated for multiple jet flow boundary conditions by varying the flap length and nozzle pressure ratio. The experimental results show that the jet flow structures over the flat plate are highly three-dimensional with strong bleeding flows from the plate sides, and that they are sensitive to plate length and nozzle pressure ratio. A multi-component force measurement device is also utilized to observe the characteristics of the jet flow thrust vectoring over the plate. The maximum thrust deflection angle of the jet is about $8^{\circ}$, demonstrating the applicability of thrust vector control via a flat plate installed at the nozzle exit.

• Journal of Pharmaceutical Investigation
• /
• 제33권3호
• /
• pp.179-185
• /
• 2003

Melatonin (MT) is an indole amide pineal hormone. It has not only very short half-life but also pH-sensitive property. The sustained release dosage form which delivers MT in a circadian fashion over 8 h is clinical value. The purpose of this study is to prepare sugar beads using multiple coating methods and enteric-coated in a sustained release to evaluate in vitro release characteristics in simulated gastric and intestinal fluids. The $Eudragit^{\circledR}$ as a polymer, sustained release membrane, and triethylcitrate (TEC) as a plasticzer were used. Multi-coated melatonin delivery system was composed of sugar, various excipients, $Eudragit^{\circledR}$ and enteric materials (e.g. hydroxy propyl methyl cellulose phthalate, HPMCP), and prepared by fluid bed coater. The dissolution test was carried out using the basket method at a stirring speed of 100 rpm at $37^{\circ}C$ in simulated gastric (pH 1.2) and intestinal fluid (pH 7.4). The released amount of MT was determined by High performance liquid chromatography method. The morhologies of surface and cross section of multi-coated beads were observed by scanning electron microscope. Size of multi-coated sugar beads was ranged over $1000{\sim}1300\;{\mu}m$. The release rate of MT from coated beads was limited in simulated gastric fluid (pH 1.2), but it was sustained in intestinal fluid (pH 7.4) during $3{\sim}8$ hours. The MT beads may provide small-intestine-targeted device for oral delivery. Studies on animal and relative experiment are in process.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2009년도 제40회 하계학술대회
• /
• pp.1551_1552
• /
• 2009

In this paper, we presented the packaging technologies of CMOS ISFET(Ion Sensitive Field Effect Transistor) pH sensor using post-CMOS process and MCP(Multi Chip Packaging). We have proposed and developed two types of packaging technology. one is one chip, which sensing layer is deposited on the gate metal of standard CMOS ISFET, the other is two chip type, which sensing layer is separated from CMOS ISFET and connected by bonding wire. These proposed packaging technologies would make it easy to fabricate CMOS ISFET pH sensor and to make variety types of pH sensor.

• 천문학회보
• /
• 제41권1호
• /
• pp.81.4-82
• /
• 2016

Recent analysis on asteroidal thermophysical property revealed that there is a tendency that their thermal inertia decrease with their sizes at least for main belt asteroids. However, little is known about the thermal properties of comet-like bodies. In this work we utilized a simple thermophysical model to calculate the thermal inertia of a bare nucleus of comet P/2006 HR30 (Siding Spring) and an asteroid in comet-like orbit 4015 Wilson-Harrington from AKARI observation data. It is also shown that the determination of their thermal inertia is very sensitive to their spin vector, while the diameter is rather easy to be constrained to a certain range by combining multi-wavelength observational data. Thus, we set diameter and hence the geometric albedo as fixed parameters, and inferred the spin vector and thermal inertia of the targets. Further detailed analyses on these cometary bodies will shed light on our understanding of the detailed surfacial characteristics of them.

• Earthquakes and Structures
• /
• 제20권3호
• /
• pp.239-260
• /
• 2021

Torsional response of buildings is attributed to poor structural configurations in plan, which arises due to two factors - torsional eccentricity and torsional flexibility. Usually, building codes address effects due to the former. This study examines both of these effects. Buildings with torsional eccentricity (e.g., those with large eccentricity) and with torsional flexibility (those with torsional mode as a fundamental mode) demand large deformations of vertical elements resisting lateral loads, especially those along the building perimeter in plan. Lateral-torsional responses are studied of unsymmetrical buildings through elastic and inelastic analyses using idealised single-storey building models (with two degrees of freedom). Displacement demands on vertical elements distributed in plan are non-uniform and sensitive to characteristics of both structure and earthquake ground motion. Limits are proposed to mitigate lateral-torsional effects, which guides in proportioning vertical elements and restricts amplification of lateral displacement in them and to avoid torsional mode as the first mode. Nonlinear static and dynamic analyses of multi-storey buildings are used to validate the limits proposed.