• Title/Summary/Keyword: Initial acquisition

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Simulation combined transfer learning model for missing data recovery of nonstationary wind speed

  • Qiushuang Lin;Xuming Bao;Ying Lei;Chunxiang Li
    • Wind and Structures
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    • v.37 no.5
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    • pp.383-397
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    • 2023
  • In the Structural Health Monitoring (SHM) system of civil engineering, data missing inevitably occurs during the data acquisition and transmission process, which brings great difficulties to data analysis and poses challenges to structural health monitoring. In this paper, Convolution Neural Network (CNN) is used to recover the nonstationary wind speed data missing randomly at sampling points. Given the technical constraints and financial implications, field monitoring data samples are often insufficient to train a deep learning model for the task at hand. Thus, simulation combined transfer learning strategy is proposed to address issues of overfitting and instability of the deep learning model caused by the paucity of training samples. According to a portion of target data samples, a substantial quantity of simulated data consistent with the characteristics of target data can be obtained by nonstationary wind-field simulation and are subsequently deployed for training an auxiliary CNN model. Afterwards, parameters of the pretrained auxiliary model are transferred to the target model as initial parameters, greatly enhancing training efficiency for the target task. Simulation synergy strategy effectively promotes the accuracy and stability of the target model to a great extent. Finally, the structural dynamic response analysis verifies the efficiency of the simulation synergy strategy.

A Comparative Analysis of GBEF According to Image Aquisition Method in Hepatobiliary Scan (간담도스캔의 영상수집방법에 따른 담즙배출율의 비교분석)

  • Kim, Yeong-Seon;Seo, Myeong-Deok;Lee, Wan-Kyu;Song, Jae-Beom
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.2
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    • pp.8-16
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    • 2014
  • Purpose The quantitative analysis of gallbladder emptying is very important in diagnosis of motility disorder of gallbladder and in biliary physiology. The GBEF obtain the statics aquisition method or the dynamic acquisition method in two ways. The purpose of this study is to compare the GBEF value of statics acquisition method and the dynamic acquisition method. And we find the best way for calculate GBEF. Materials and Methods The quantitative hepatobiliary scan with $^{99m}Tc$-mebrofenin was performed of 27 patients. Initial images were acquired statically, for 60 min after injection of the radioactive tracer. And if the gallbladder is visualized to 60 min, performed stimulation of gallbladder (1egg, 200 mL milk). After that, started acquisition of dynamic image for 30 min. After that, image of after fatty meal of the statics method were acquired on equal terms with 60 min image. The statics GBEF was calculated using the images of before fatty meal and post fatty meal by the statics method. The dynamic GBEF was calculated using the images of time of maximum bile juice uptake ($T_{max}$) and time of minimum bile juice uptake ($T_{min}$) images from the gallbladder time-activity curve. A bile juice is secreted from gallbladder while eating a fatty meal. that is named early GBEF and that was calculated using before fatty meal image of the statics method and 1 min image of the dynamic method. Results The result saw very big difference between two according to $T_{max}$. The result, were as follows. 1) In case of less than 1 min, the dynamic mean GBEF was $40.1{\pm}21.7%$, the statics mean GBEF was $51.5{\pm}23.6%$ in 16 cases. The early mean GBEF was $14.0{\pm}29.1%$. The GBEF of statics method was higher because that include secreted bile juice while performed stimulation of gallbladder. A difference of GB counts according to acquisition method and the early bile juice counts was $17.6{\pm}14.8%$ and $13.5{\pm}15.3%$. 2) In case of exceed than 1 min, the dynamic mean GBEF was $31.0{\pm}19.7%$, the statics mean GBEF was $21.3{\pm}19.4%$ in 7 cases. The early GBEF was $-6.9{\pm}4.9%$. The GBEF of dynamic method was higher because that include concentrated bile juice to $T_{max}$. A difference of GB counts according to acquisition method and the early bile juice counts was $14.3{\pm}7.3%$ and $5.9{\pm}3.9%$. Conclusion The statics method is very easy and simple, but in case of $T_{max}$ delay, the GBEF can be lower. The dynamic method is able to calculate accurately in case of $T_{max}$ delay, but in case of $T_{max}$ is less than 1 min, the GBEF can be lower because dynamic GBEF exclude secreted bile juice while performed stimulation of gallbladder. The best way to calculate GBEF is to scan with dynamic method preferentially and to choose suitable method between the two way after conform $T_{max}$ on the T-A curve of the dynamic method.

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[ $^{18}F-FDG$ ] PET/CT in Multiple Myeloma: Is It Necessary to Include the Skull and Lower Extremity Distal to Mid-Thigh? (다발성 골수종에서의 $^{18}F$-FDG PET/CT: 전신영상 획득이 필요한가?)

  • Lee, Su-Jin; Choi, Joon-Young;Kim, Ki-Hyun;Lee, Eun-Jeong;Cho, Young-Seok;Hyun, Seung-Hyup;Lee, Ji-Young;Lee, Kyung-Han;Kim, Byung-Tae
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.1
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    • pp.39-43
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    • 2008
  • Purpose: We evaluated whether it was necessary to perform whole body acquisition of $^{18}F$-FDG PET/CT including whole skull and lower extremity (LE) distal to mid-thigh (MT) in patients with multiple myeloma (MM). Materials and Methods: Thirty patients underwent 45 whole body $^{18}F$-FDG PET/CT scans including skull and LE distal to MT. PET scans were divided by 2 subgroups according to the presence of abnormal focal $^{18}F$-FDG uptake in skull or LE distal to MT. Clinical characteristics including age, sex, and stages were compared between the 2 subgroups. Results: Of total 45 whole body PET/CT scans, focally increased abnormal FDG uptake in the skull or LE distal to MT suggesting myeloma involvement was found in 22 scans (48.9%) of 14 patients (46.7%). Skull lesions were more frequently observed than LE lesions distal to MT on PET (86.4% vs. 40.9%, p<0.005). There were no significant differences in age, sex, initial Durie/Salmon stage, and tumor burden at the time of PET scan suggested by serum hemoglobin level, serum calcium level, serum and urine paraprotein level, and serum creatinine level between the two subgroups. The presence of the skull or LE distal MT lesions on PET did not affect on the Durie/Salmon plus stage except only 1 case (1/22, 4.5%, p>0.05). Conclusion: Abnormal lesions in the skull or LE distal to MT on $^{18}F$-FDG PET/CT did not affect significantly on the tumor burden and Durie/Salmon plus stage of MM. Therefore, torso PET acquisition including head may be sufficient for evaluating patients with MM.

Research on the Critical Factors Affecting Taiwan Secondary School Teachers' Initial Acquisition of Formal Teaching Position

  • Tien, Shiaw-Wen;Chiu, Chung-Ching;Tsai, Chih-Hung;Chung, Yi-Chan;Chang, Ya-Chin
    • International Journal of Quality Innovation
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    • v.8 no.3
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    • pp.123-155
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    • 2007
  • This research treated the secondary school teachers as the research scale and the research targets included the following: secondary school (employ unit), center of teacher education, and qualified teachers. In terms of these three groups of people, the topics of exploration focused on the perception of suitable teachers, perception of evaluation standard during the process of teacher examination and the relationship among teacher examination systems. The research was managed by two phases: the first phase referred to literature reorganization, expert interview, the qualities and conditions of suitable teachers, important evaluation standard during the process of teacher examination and teacher examination system used; the second phase included questionnaire survey, employ school acquisition, the perception of centers of teacher education and qualified teachers toward the suitability condition and examination evaluation standard in the first phase and teacher examination system used. This research found out that as to the perception of suitable teachers, through data collection, there were six factors reorganized. The levels of their importance were as follows: education devotion, teaching capacity, class management, capacity to guide special students, capacity to communicate with the parents and the will to undertake administrative works. Noticeably, employee unit and centers of teacher education apparently valued class management more, compared with trained teachers; as to evaluation standard of examination, the analytical result found out that the perception of three groups were different in terms of the views toward educational works, written examination data, candidate's age, club experience at school and capacity to use multimedia support teaching materials. This research further proposed six suggestions for centers of teacher education and trained teachers: (l) employ schools considerably valued educational devotion; (2) trained teachers tended to neglect the importance of class management; (3) employee unit considerably cared about the new teachers' competence to use multimedia support teaching materials; however, trained teachers did not have the same view; (4) employee unit considerably cared about new teachers' views toward educational works as well as the candidates' ages; (5) generally speaking, trained teachers neglected the importance of club experience at school; (6) the data revealed that written examination data was not relatively important in terms of teacher examination.

A Technique on the 3-D Terrain Analysis Modeling for Optimum Site Selection and development of Stereo Tourism in the Future (미래입체관광의 최적지선정 및 개발을 위한 3차원지형분석모델링 기법)

  • Yeon, Sang-Ho;Choi, Seung-Kuk
    • The Journal of the Korea Contents Association
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    • v.13 no.11
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    • pp.415-422
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    • 2013
  • The contents development for the Internet and cyber tour has been attempted in a number of areas. 3D topography of the spatial environment, land planning and land information contents as a 3D tour of the future ubiquitous city safe for tourism due to the implementation of information made available major area. Domestic service, and in urban areas of the country where land and precise spatial information in order to shoot satellites and aircraft in the area you want to mount the camera on a variety of photo images taken by conducting 3D spatial that is required is able to obtain the information. Geo spatial information in a variety of direct or indirect acquisition of the initial spatial data into a database for accurate collection, storage, editing, manipulation and application technology changes in the future by establishing a database of 3D spatial by securing content organization ubiquitous tourist to take advantage of new tourism industry was greatly. As a result of this study for future tourism using geo spatial information and analysis of 3D modeling by intelligent land information indirectly, with quite a few stereo site experience and a variety of tourist spatial acquisition and utilization of information could prove.

Molecular Analysis of Colonized Bacteria in a Human Newborn Infant Gut

  • Park Hee-Kyung;Shim Sung-Sub;Kim Su-Yung;Park Jae-Hong;Park Su-Eun;Kim Hak-Jung;Kang Byeong-Chul;Kim Cheol-Min
    • Journal of Microbiology
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    • v.43 no.4
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    • pp.345-353
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    • 2005
  • The complex ecosystem of intestinal micro flora is estimated to harbor approximately 400 different microbial species, mostly bacteria. However, studies on bacterial colonization have mostly been based on culturing methods, which only detect a small fraction of the whole microbiotic ecosystem of the gut. To clarify the initial acquisition and subsequent colonization of bacteria in an infant within the few days after birth, phylogenetic analysis was performed using 16S rDNA sequences from the DNA iso-lated from feces on the 1st, 3rd, and 6th day. 16S rDNA libraries were constructed with the amplicons of PCR conditions at 30 cycles and $50^{\circ}C$ annealing temperature. Nine independent libraries were produced by the application of three sets of primers (set A, set B, and set C) combined with three fecal samples for day 1, day 3, and day 6 of life. Approximately 220 clones ($76.7\%$) of all 325 isolated clones were characterized as known species, while other 105 clones ($32.3\%$) were characterized as unknown species. The library clone with set A universal primers amplifying 350 bp displayed increased diversity by days. Thus, set A primers were better suited for this type of molecular ecological analysis. On the first day of the life of the infant, Enterobacter, Lactococcus lactis, Leuconostoc citreum, and Streptococcus mitis were present. The largest taxonomic group was L. lactis. On the third day of the life of the infant, Enterobacter, Enterococcus faecalis, Escherichia coli, S. mitis, and Streptococcus salivarius were present. On the sixth day of the life of the infant, Citrobacter, Clostridium difficile, Enterobacter sp., Enterobacter cloacae, and E. coli were present. The largest taxonomic group was E. coli. These results showed that microbiotic diversity changes very rapidly in the few days after birth, and the acquisition of unculturable bacteria expanded rapidly after the third day.

An SE-Based System Architecture Process for Submarine's Basic Design (잠수함 기본설계를 위한 SE 기반 시스템 아키텍처 프로세스)

  • Shin, Sung-Chul;Park, Jin-Won;Lee, Jae-Chon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.3
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    • pp.91-99
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    • 2019
  • Naval Ships have a number of requirements related to performance. Naval ship acquisition takes a long time from initial planning to delivery, and various products such as drawings and reports are created. In complex systems, such as naval ships, it is difficult to maintain the required traceability through these outputs. The basic design of the ship is an important step to determine the specifications, performance, and equipment of the ship. It is necessary to apply the systematic requirements management process. The basic design manages the requirements in accordance with the systems engineering-based technical review process, but the actual system architecture design process is not presented. The traceability between the requirements and the functional and physical architectures of components is unclear. This paper examined how to design the system architecture required for specification and system design, and the design results were verified using SE-based technical review process for requirements management. A step-by-step process for designing a submarine system architecture is presented and verified using the SE technical review. This facilitates the specification of the requirements and system architecture design, and supports traceability management and verification of the requirements. The proposed process can be applied in various ships including submarines.

Development of Stream Cover Classification Model Using SVM Algorithm based on Drone Remote Sensing (드론원격탐사 기반 SVM 알고리즘을 활용한 하천 피복 분류 모델 개발)

  • Jeong, Kyeong-So;Go, Seong-Hwan;Lee, Kyeong-Kyu;Park, Jong-Hwa
    • Journal of Korean Society of Rural Planning
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    • v.30 no.1
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    • pp.57-66
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    • 2024
  • This study aimed to develop a precise vegetation cover classification model for small streams using the combination of drone remote sensing and support vector machine (SVM) techniques. The chosen study area was the Idong stream, nestled within Geosan-gun, Chunbuk, South Korea. The initial stage involved image acquisition through a fixed-wing drone named ebee. This drone carried two sensors: the S.O.D.A visible camera for capturing detailed visuals and the Sequoia+ multispectral sensor for gathering rich spectral data. The survey meticulously captured the stream's features on August 18, 2023. Leveraging the multispectral images, a range of vegetation indices were calculated. These included the widely used normalized difference vegetation index (NDVI), the soil-adjusted vegetation index (SAVI) that factors in soil background, and the normalized difference water index (NDWI) for identifying water bodies. The third stage saw the development of an SVM model based on the calculated vegetation indices. The RBF kernel was chosen as the SVM algorithm, and optimal values for the cost (C) and gamma hyperparameters were determined. The results are as follows: (a) High-Resolution Imaging: The drone-based image acquisition delivered results, providing high-resolution images (1 cm/pixel) of the Idong stream. These detailed visuals effectively captured the stream's morphology, including its width, variations in the streambed, and the intricate vegetation cover patterns adorning the stream banks and bed. (b) Vegetation Insights through Indices: The calculated vegetation indices revealed distinct spatial patterns in vegetation cover and moisture content. NDVI emerged as the strongest indicator of vegetation cover, while SAVI and NDWI provided insights into moisture variations. (c) Accurate Classification with SVM: The SVM model, fueled by the combination of NDVI, SAVI, and NDWI, achieved an outstanding accuracy of 0.903, which was calculated based on the confusion matrix. This performance translated to precise classification of vegetation, soil, and water within the stream area. The study's findings demonstrate the effectiveness of drone remote sensing and SVM techniques in developing accurate vegetation cover classification models for small streams. These models hold immense potential for various applications, including stream monitoring, informed management practices, and effective stream restoration efforts. By incorporating images and additional details about the specific drone and sensors technology, we can gain a deeper understanding of small streams and develop effective strategies for stream protection and management.

A Comparative Study on the Information Use Patterns of Science & Technology Researchers (과학기술 연구자 정보이용행태에 관한 비교 탐색 연구)

  • Choi, Woo-Seok;Yang, Dong-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.4
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    • pp.1946-1952
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    • 2014
  • The purpose of this study is to suggest some improvements of information service on the Internet through a comparative analysis of information use patterns of science and technology researchers in universities, research institutes and business enterprises. We classify information use patterns into information use purpose, information use types, a frequently used/referenced portal site, the initial method of internet search, information service selection factors and the channels of off-line information acquisition. The results of this study are as follows: First, according to frequency analysis, there are some information use patterns among S & T research groups. Second, according to ${\chi}^2$ analysis, there are some significant differences in ratio of information use patterns among them.

3D Generic Vertebra Model for Computer Aided Diagnosis (컴퓨터를 이용한 의료 진단용 3차원 척추 제네릭 모델)

  • Lee, Ju-Sung;Baek, Seung-Yeob;Lee, Kun-Woo
    • Korean Journal of Computational Design and Engineering
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    • v.15 no.4
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    • pp.297-305
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    • 2010
  • Medical image acquisition techniques such as CT and MRI have disadvantages in that the numerous time and efforts are needed. Furthermore, a great amount of radiation exposure is an inherent proberty of the CT imaging technique, a number of side-effects are expected from such method. To improve such conventional methods, a number of novel methods that can obtain 3D medical images from a few X-ray images, such as algebraic reconstruction technique (ART), have been developed. Such methods deform a generic model of the internal body part and fit them into the X-ray images to obtain the 3D model; the initial shape, therefore, affects the entire fitting process in a great deal. From this fact, we propose a novel method that can generate a 3D vertebraic generic model based on the statistical database of CT scans in this study. Moreover, we also discuss a method to generate patient-tailored generic model using the facts obtained from the statistical analysis. To do so, the mesh topologies of CT-scanned 3D vertebra models are modified to be identical to each other, and the database is constructed based on them. Furthermore, from the results of a statistical analysis on the database, the tendency of shape distribution is characterized, and the modeling parameters are extracted. By using these modeling parameters for generating the patient-tailored generic model, the computational speed and accuracy of ART can greatly be improved. Furthermore, although this study only includes an application to the C1 (Atlas) vertebra, the entire framework of our method can be applied to other body parts generally. Therefore, it is expected that the proposed method can benefit the various medical imaging applications.