• Title/Summary/Keyword: Transparent cloud

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A Study on Daytime Transparent Cloud Detection through Machine Learning: Using GK-2A/AMI (기계학습을 통한 주간 반투명 구름탐지 연구: GK-2A/AMI를 이용하여)

  • Byeon, Yugyeong;Jin, Donghyun;Seong, Noh-hun;Woo, Jongho;Jeon, Uujin;Han, Kyung-Soo
    • Korean Journal of Remote Sensing
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    • v.38 no.6_1
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    • pp.1181-1189
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    • 2022
  • Clouds are composed of tiny water droplets, ice crystals, or mixtures suspended in the atmosphere and cover about two-thirds of the Earth's surface. Cloud detection in satellite images is a very difficult task to separate clouds and non-cloud areas because of similar reflectance characteristics to some other ground objects or the ground surface. In contrast to thick clouds, which have distinct characteristics, thin transparent clouds have weak contrast between clouds and background in satellite images and appear mixed with the ground surface. In order to overcome the limitations of transparent clouds in cloud detection, this study conducted cloud detection focusing on transparent clouds using machine learning techniques (Random Forest [RF], Convolutional Neural Networks [CNN]). As reference data, Cloud Mask and Cirrus Mask were used in MOD35 data provided by MOderate Resolution Imaging Spectroradiometer (MODIS), and the pixel ratio of training data was configured to be about 1:1:1 for clouds, transparent clouds, and clear sky for model training considering transparent cloud pixels. As a result of the qualitative comparison of the study, bothRF and CNN successfully detected various types of clouds, including transparent clouds, and in the case of RF+CNN, which mixed the results of the RF model and the CNN model, the cloud detection was well performed, and was confirmed that the limitations of the model were improved. As a quantitative result of the study, the overall accuracy (OA) value of RF was 92%, CNN showed 94.11%, and RF+CNN showed 94.29% accuracy.

A Research on the Cloud Computing Security Framework (클라우드 컴퓨팅 정보보호 프레임워크에 관한 연구)

  • kim, Jung-Duk;Lee, Seong-Il
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.23 no.6
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    • pp.1277-1286
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    • 2013
  • Cloud computing's unique attributes such as elasticity, rapid provisioning and releasing, resource pooling, multi-tenancy, broad-network accessibility, and ubiquity bring many benefits to cloud adopters(company and organization), but also entails specific security risks associated with the type of adopted cloud and deployment mode. To minimize those types of risk, this paper proposed cloud computing security framework refered to strategic alliance model. The cloud computing security framework has main triangles that are cloud threat, security controls, cloud stakeholders and compose of three sides that are purposefulness, accountability, transparent responsibility. Main triangles define purpose of risk minimization, appointment of stakeholders, security activity for them and three sides of framework are principles of security control in the cloud computing, provide direction of deduction for seven service packages.

Comparative Ultrastructure of the Fertilized Egg Envelope in Three Species, Cyprinidae, Teleost (경골어류 잉어과 3종의 수정란 난막 미세구조 비교)

  • Kim, Dong-Heui;Reu, Dong-Suck;Deung, Young-Kun
    • Applied Microscopy
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    • v.28 no.2
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    • pp.237-253
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    • 1998
  • The structures of the fertilizedegg envelope in threespecies of cyprinidae, leoparddanio (Brachydanio frankei), cherry barb (Barbustitteya) and white cloudmountain fish (Tanichthys albonubes) were investigated by light and electron microscopy. The fertilized eggs of all three species have colorless, transparent, spherical and non-floted type. The egg envelopes have a single micropylewhich is thought to the pathway of sperm in the area of the animal pole. Also, an outer layersof both cherry barband white cloud mountain fish areadhesive types, but in that of leoparddanio has non-adhesivetype. In leopard danio, an outer surface ofegg envelope is covered by mushroom-likestructure, that of cherry barb is arranged by button-like structure, and that of white cloud mountain fish isarranged by rod-likestructure. Inboth leopard danioand cherrybarb, the eggenvelopes consist of three distinct layers; an outer layer, a middle layer and an inner layer, and that of white cloud mountain fish hastwo layers. An innerlayer of egg envelopein leopard danio consist of 10 layers, cherry barb has 8 layers, and white cloud mountain fish has $5\sim6$ layers.

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Web Service Connection Management Scheme for Seamless Migration of User Workspace in Cloud Computing (클라우드 컴퓨팅에서 사용자 작업환경의 끊김 없는 연계를 위한 웹 서비스 연결 관리 기법)

  • Choi, Min
    • Journal of Information Technology Services
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    • v.8 no.1
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    • pp.193-202
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    • 2009
  • Cloud computing emerges as a new computing paradigm which targets reliable and customizable services. The term builds on decades of research in virtual machine, distributed and parallel computing, utility computing, and more recently networking, web service, and software as a service. In this paper, we provide a seamless connection migration of web services. This is useful for cloud computing environment in which many client terminals have mobility. With the wireless internet facility, those mobile users can move place to place during internet communication. Therefore, we provide solutions to the two major problems in current virtualization based migration: communication failure problems and connection re-establishment. Communication channel flushing by zero window notification helps to resolve the communication failure problems and TCP port inheritance prevents connection re-establishment errors during socket reconstruction. Thus, our web service migration facility is now able to preserve open network connections, and even for server sockets. This is a highly transparent approach, in that we did not Introduce additional messages for channel flushing and did not make any modification to the TCP protocol stack. Experimental results show that the overhead due to connection migration of web services is almost negligible when compared with time to take the conventional web service migration.

Improving Data Availability by Data Partitioning and Partial Overlapping on Multiple Cloud Storages (다수 클라우드 스토리지로의 데이터 분할 및 부분 중복을 통한 데이터 가용성 향상)

  • Park, Jun-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.12B
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    • pp.1498-1508
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    • 2011
  • A cloud service customer has no other way but to wait for his lost data to be recovered by the cloud service provider when the data was lost or not accessible for a while due to the provider's system failure, cracking attempt, malfunction, or outage. We consider a solution to address this problem that can be implemented in the cloud client's domain, rather than in the cloud service provider's domain. We propose a high level architecture and scheme for successfully retrieving data units even when several cloud storages are not accessible at the same time. The scheme is based on a clever way of partitioning and partial overlapping of data for being stored on multiple cloud storages. In addition to providing a high level of data availability, the scheme makes it possible to re-encrypt data units with new keys in a user transparent way, and can produce the complete log of every user's data units accessed, for assessing data disclosure, if needed.

Design and Implementation of an Alternate System Interconnect based on PCI Express (PCI Express 기반 시스템 인터커넥트의 설계 및 구현)

  • Kim, Young Woo;Ren, Ye;Choi, WonHyuk
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.8
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    • pp.74-85
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    • 2015
  • PCI Express is a well-known and widely used de-facto system bus standard for connecting among a processor and IO devices. PCI Express is originated from old PCI standard, and its most of applications are limited to be used within a PC or server system. But, because of its fast speed, low power consumption, and good protocol efficiency, it is considered as one of a good candidate for an alternate system interconnect for many years. In this paper, we present design, implementation and early evaluation of an alternate system interconnect by utilizing PCI Express. The developed alternate system interconnect using PCI Express (named PCIeLINK) utilizes non-transparent bridging (NTB) technic which generally used in fail-over system in PCI and PCI Express. By using NTB technic, PCI Express device can be extended to outside of a system without electrical and logical problems arising during system boot and enumeration. To build up an alternate system interconnect, we designed and implemented a network interface card having multiple PCI Express ${\times}4$ connections (theoretically 20 Gbps) and tested, The early test results revealed that an ${\times}4$ port in the card showed 8.6 Gbps peak performance for bulk transmission and 5.1 Gbps peak for normal TCP/IP transfer.

Removal of Post Etch/Ash Residue on an Aluminum Patterned Wafer Using Supercritical CO2 Mixtures with Co-solvents and Surfactants: sc-CO2 Mixture for the Removal of Post Etch/Ash Residue

  • You, Seong-sik
    • Journal of the Semiconductor & Display Technology
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    • v.16 no.1
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    • pp.22-28
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    • 2017
  • The result of stripping process for the removal of the post etch/ash Photoresist (PR) residue on an aluminum patterned wafer by using supercritical $CO_2$ ($sc-CO_2$) mixture, was investigated by scanning of electron microscope (SEM) inspection of wafer, measuring the cloud points and visual observation of the state of $sc-CO_2$ mixtures. It was found that $sc-CO_2$ mixtures were made by mixing additives and $sc-CO_2$ should form homogeneous and transparent phase (HTP) in order to effectively and uniformly remove the post etch/ash PR residue on the aluminum patterned wafer using them. The additives were formulated by mixing and co-solvents like an amine compound and fluorosurfactants used as HTP agents, and the PR residue on the wafer were able to be rapidly and effectively removed using the $sc-CO_2$ mixture of HTP. The five kinds of additives were formulated by the recipe of mixing co-solvents and surfactants, which were able to remove PR residue on the wafer by mixing with $sc-CO_2$ at the stripping temperature range from 40 to $80^{\circ}C$. The five kinds of $sc-CO_2$ mixtures which were named as PR removers were made, which were able to form HTP within the above described stripping temperature. The cloud points of $sc-CO_2$ mixtures were measured to find correlation between them and HTP.

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Measurement of Wax Appearance Temperature Using Image Processing (영상 처리기법을 이용한 오일의 왁스생성온도 측정)

  • Hwang, Soon-Hye;Kang, Pan-Sang;Lim, Jong-Se
    • Journal of Energy Engineering
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    • v.25 no.1
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    • pp.1-8
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    • 2016
  • When the oil is produced in the low temperature environment, wax can be accumulated in petroleum production system(pipeline, riser) and causes problems such as pipeline stucking, disturbance of the oil production. These problems can be lead to time-consuming and economic losses for flow assurance. For prediction and mitigation of wax deposition, it is necessary to measure the Wax Appearance Temperature(WAT) which is a temperature when the wax crystals start to be formed. WAT standard measurement method of transparent oil has to determine the cloud point of sample to the naked eye and cannot be applied to continuous change of the temperature. In this study, wax behavior of transparent oil samples are recorded depending on temperature using Visualized WAT Measurement System. Also, WATs of transparent oil samples are measured by image processing and compared with the result of the standard method.

Transparent Manipulators Accomplished with RGB-D Sensor, AR Marker, and Color Correction Algorithm (RGB-D 센서, AR 마커, 색수정 알고리즘을 활용한 매니퓰레이터 투명화)

  • Kim, Dong Yeop;Kim, Young Jee;Son, Hyunsik;Hwang, Jung-Hoon
    • The Journal of Korea Robotics Society
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    • v.15 no.3
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    • pp.293-300
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    • 2020
  • The purpose of our sensor system is to transparentize the large hydraulic manipulators of a six-ton dual arm excavator from the operator camera view. Almost 40% of the camera view is blocked by the manipulators. In other words, the operator loses 40% of visual information which might be useful for many manipulator control scenarios such as clearing debris on a disaster site. The proposed method is based on a 3D reconstruction technology. By overlaying the camera image from front top of the cabin with the point cloud data from RGB-D (red, green, blue and depth) cameras placed at the outer side of each manipulator, the manipulator-free camera image can be obtained. Two additional algorithms are proposed to further enhance the productivity of dual arm excavators. First, a color correction algorithm is proposed to cope with the different color distribution of the RGB and RGB-D sensors used on the system. Also, the edge overlay algorithm is proposed. Although the manipulators often limit the operator's view, the visual feedback of the manipulator's configurations or states may be useful to the operator. Thus, the overlay algorithm is proposed to show the edge of the manipulators on the camera image. The experimental results show that the proposed transparentization algorithm helps the operator get information about the environment and objects around the excavator.

Design of Mixed Reality based Convergence Edutainment System using Cloud Service (클라우드 서비스를 이용한 복합현실 기반의 융합형 에듀테인먼트 시스템 설계)

  • Kim, Donghyun;Kim, Minho
    • Journal of the Korea Convergence Society
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    • v.6 no.3
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    • pp.103-109
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    • 2015
  • TOLED(Transparent, Organic Light Emitting Diodes) based edutainment system has been studied to solve the actual feeling training and educational experience problem of e-learning. However, edutainment system using TOLED has a problem for the non-detection of multi marker array and rotate marker array, and it has problem for the dissonance phenomena caused by Illumination Environment between real world and virtual object. It also has a do not provide services through a variety of devices problem. Therefore, in this paper, we designed a system that provides a realistic actual feeling edutainment contents by recognizes the marker array rotation and a plurality of marker arrangement via an improved marker detection technique. And to unify the real space and virtual space of the lighting environment through a nested block layer.