• Title/Summary/Keyword: Contrast Scale

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Design and Implementation of a Hardware Accelerator for Marine Object Detection based on a Binary Segmentation Algorithm for Ship Safety Navigation (선박안전 운항을 위한 이진 분할 알고리즘 기반 해상 객체 검출 하드웨어 가속기 설계 및 구현)

  • Lee, Hyo-Chan;Song, Hyun-hak;Lee, Sung-ju;Jeon, Ho-seok;Kim, Hyo-Sung;Im, Tae-ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.10
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    • pp.1331-1340
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    • 2020
  • Object detection in maritime means that the captain detects floating objects that has a risk of colliding with the ship using the computer automatically and as accurately as human eyes. In conventional ships, the presence and distance of objects are determined through radar waves. However, it cannot identify the shape and type. In contrast, with the development of AI, cameras help accurately identify obstacles on the sea route with excellent performance in detecting or recognizing objects. The computer must calculate high-volume pixels to analyze digital images. However, the CPU is specialized for sequential processing; the processing speed is very slow, and smooth service support or security is not guaranteed. Accordingly, this study developed maritime object detection software and implemented it with FPGA to accelerate the processing of large-scale computations. Additionally, the system implementation was improved through embedded boards and FPGA interface, achieving 30 times faster performance than the existing algorithm and a three-times faster entire system.

Spatial Analysis of Wind Trajectory Prediction According to the Input Settings of HYSPLIT Model (HYSPLIT 모형 입력설정에 따른 바람 이동경로 예측 결과 공간 분석)

  • Kim, Kwang Soo;Lee, Seung-Jae;Park, Jin Yu
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.23 no.4
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    • pp.222-234
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    • 2021
  • Airborne-pests can be introduced into Korea from overseas areas by wind, which can cause considerable damage to major crops. Meteorological models have been used to estimate the wind trajectories of airborne insects. The objective of this study is to analyze the effect of input settings on the prediction of areas where airborne pests arrive by wind. The wind trajectories were predicted using the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. The HYSPLIT model was used to track the wind dispersal path of particles under the assumption that brown plant hopper (Nilaparvata lugens) was introduced into Korea from sites where the pest was reported in China. Meteorological input data including instantaneous and average wind speed were generated using meso-scale numerical weather model outputs for the domain where China, Korea, and Japan were included. In addition, the calculation time intervals were set to 1, 30, and 60 minutes for the wind trajectory calculation during early June in 2019 and 2020. It was found that the use of instantaneous and average wind speed data resulted in a considerably large difference between the arrival areas of airborne pests. In contrast, the spatial distribution of arrival areas had a relatively high degree of similarity when the time intervals were set to be 1 minute. Furthermore, these dispersal patterns predicted using the instantaneous wind speed were similar to the regions where the given pest was observed in Korea. These results suggest that the impact assessment of input settings on wind trajectory prediction would be needed to improve the reliability of an approach to predict regions where airborne-pest could be introduced.

A Study on the Spatial Distribution of the Vacant Houses and their Accessibility : Focused on the Vacant Houses in Okcheon-gun, Chungcheongbuk-do (빈집 공간분포 특성 및 접근성에 관한 연구 : 충청북도 옥천군 빈집을 중심으로)

  • Lee, Jong-Soo;Kim, Sun-Duck
    • The Journal of the Korea Contents Association
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    • v.21 no.12
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    • pp.791-802
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    • 2021
  • In Korea, the cities continue to deteriorate, while the vacant houses in the small local towns emerge as a serious social problem. Despite the vacant houses emerge as a serious social problem in the small local towns as well as in the large cities, the basic researches into them are yet to be conducted on a full scale. Thus, in order to know about the spatial distribution of the vacant houses, this study conducted the square analysis and the kernel density analysis. As a result, it was confirmed that the vacant houses in Okcheon-gun had certain crowding forms and characteristics at the level of statistical significance. Next, in order to examine the distribution of the vacant houses in terms of the accessibility to the living SOC facilities, the GIS network analysis was performed, focusing on the major facilities and road networks. As a result, it was found that the better the accessibility to the living SOC facilities such as medical and well-being was, the ratio of the vacant houses was lower. In contrast, it was found that the accessibility to the obligatory facilities such as public administration and educational facilities did not have any important effects on the distribution of the vacant houses. All in all, through this study, the spatial distribution of the vacant houses in the small local town and their accessibility to the major SOC facilities could be analyzed.

Effects of Practical Training Using 3D Printed Structure-Based Blind Boxes on Multi-Dimensional Radiographic Image Interpretation Ability (3D 프린팅 구조물 기반 블라인드박스를 이용한 실습교육이 다차원 방사선영상해독력에 미치는 효과)

  • Youl-Hun, Seoung
    • Journal of the Korean Society of Radiology
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    • v.17 no.1
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    • pp.131-139
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    • 2023
  • In this study, we are purposed to find the educational effect of practical training using a 3D printed structure-based blind box on multidimensional radiographic image interpretation. The subjects were 83 (male: 49, female: 34) 2nd year radiological science students who participated in the digital medical imaging practice that was conducted for 3 years from 2020 to 2022. The learning method used 3D printing technology to print out the inside structure of the blind box designed by itself. After taking X-rays 3 times (x, y, z axis), the structure images in the blind box were analyzed for each small group. We made the 3D structure that was self-made with clay based on our 2D radiographic images. After taking X-rays of the 3D structure, it was compared whether it matches the structural image of the blind box. The educational effect for the practical training surveyed class faithfulness, radiographic image interpretation ability (attenuation concept, contrast concept, windowing concept, 3-dimensional reading ability), class satisfaction (interest, external recommendation, immersion) on a 5-point Likert scale as an anonymous student self-writing method. As a result, all evaluation items had high positive effects without significant differences between males and females. Practical education using blind boxes is a meaningful example of radiology education technology using 3D printing technology, and it is expected to be used as content to improve students' problem-solving skills and increase satisfaction with major subjects.

A Longitudinal Analysis of Residential Environment Quality and Housing Expense of Young Households (청년층 가구의 주거실태 변화에 관한 종단 분석)

  • Lee, Hyunjeong;Yim, Taegyun
    • Land and Housing Review
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    • v.13 no.2
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    • pp.31-47
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    • 2022
  • This paper examines residential environment quality and housing expenses of young households through longitudinal analysis. Using the 5th and 15th Korea Welfare Panel Study (KoWePS), this research compared their housing outcomes with those of the Korean households. The statistical analysis revealed that most young households were highly-educated, salaried workers who were predominantly married men in their early 30s. There was a sharp rise in the number of female householders and one-person households. Also, the young households were largely renters of mid-sized multi-family housing with two bedrooms in non-Seoul Metropolitan Area. Their housing expense was slightly higher than the national average. As a proportion of renters of multi-family housing (exclusive of apartments) rose, the proportion of young households who spent more than 25% of their income increased faster than the national average. The proportion of young households in the Seoul Metropolitan Area outpaced the national average. Their monthly rental arrangements grew in contrast to no change in the nationwide monthly rental arrangement over the survey period, resulting in their high burden on housing expenses. Their homeownership rate was below the national average, and it decreased while the overall homeownership rate increased nationwide, implying that their housing affordability was worsened, which made it difficult for them to move up the housing ladder. Thus, this research suggests housing policies that scale up support for young households.

Influence of kilovoltage- peak and the metal artifact reduction tool in cone-beam computed tomography on the detection of bone defects around titanium-zirconia and zirconia implants

  • Fontenele, Rocharles Cavalcante;Nascimento, Eduarda Helena Leandro;Imbelloni-Vasconcelos, Ana Catarina;Martins, Luciano Augusto Cano;Pontual, Andrea dos Anjos;Ramos-Perez, Flavia Maria Moraes;Freitas, Deborah Queiroz
    • Imaging Science in Dentistry
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    • v.52 no.3
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    • pp.267-273
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    • 2022
  • Purpose: The aim of this study was to assess the influence of kilovoltage- peak (kVp) and the metal artifact reduction (MAR) tool on the detection of buccal and lingual peri-implant dehiscence in the presence of titanium-zirconia (Ti-Zr) and zirconia (Zr) implants in cone-beam computed tomography (CBCT) images. Materials and Methods: Twenty implant sites were created in the posterior region of human mandibles, including control sites (without dehiscence) and experimental sites (with dehiscence). Individually, a Ti-Zr or Zr implant was placed in each implant site. CBCT scans were performed using a Picasso Trio device, with variation in the kVp setting (70 or 90 kVp) and whether the MAR tool was used. Three oral radiologists scored the detection of dehiscence using a 5-point scale. The area under the receiver operating characteristic (ROC) curve, sensitivity, and specificity were calculated and compared by multi-way analysis of variance (α=0.05). Results: The kVp, cortical plate involved (buccal or lingual cortices), and MAR did not influence any diagnostic values (P>0.05). The material of the implant did not influence the ROC curve values(P>0.05). In contrast, the sensitivity and specificity were statistically significantly influenced by the implant material (P<0.05) with Zr implants showing higher sensitivity values and lower specificity values than Ti-Zr implants. Conclusion: The detection of peri-implant dehiscence was not influenced by kVp, use of the MAR tool, or the cortical plate. Greater sensitivity and lower specificity were shown for the detection of peri-implant dehiscence in the presence of a Zr implant.

The relationship between the level of perceived parental overprotectiveness and college students' morality (대학생 자녀가 지각한 부모의 과보호 양육수준과 자녀의 도덕성 간 관계)

  • Jessica Lee Yoon;Kyong-Mee Chung
    • Korean Journal of Culture and Social Issue
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    • v.20 no.4
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    • pp.307-328
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    • 2014
  • The purpose of this study is to investigate the influence of parental overprotection on Korean college students' moral behaviors. To test the prediction that overprotected participants will show more immoral behaviors in moral dilemma situations, we measured perceived parental overprotectiveness and morality. Participants were 113 college freshmen. Two types of modified experimental paradigms were used to assess participants on their levels of justice-oriented and prosocial morality. Based on whether they displayed moral behavior (i.e., honest or helping behavior) or not, participants were included in either moral or immoral group. Second, the levels of perceived maternal overprotectiveness and paternal overprotectiveness were assessed using Korean-Parental Overprotection Scale (K-POS) and were compared between moral and immoral group. For justice-oriented morality, the results showed that the immoral group reported a significantly higher level of perceived maternal overprotection compared to the moral group (t = 2.16, p < .05). On the contrast, paternal overprotection was not related to participants' honesty. The results indicate that participants who experienced overprotective parental care are more likely to act immorally in moral dilemma situations dealing with justice. Meanwhile, for prosocial morality, both maternal and paternal overprotection levels did not result in significant difference between two groups. More Implications and limitations were discussed.

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Analysis for Economic Induced Effect of Oil and Gas E&P Industry's Business Ecosystem (산업생태계를 고려한 석유·가스개발산업의 경제적 유발효과 분석)

  • Ji Whan Kim;Yoon Kyung Kim
    • Environmental and Resource Economics Review
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    • v.31 no.4
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    • pp.669-691
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    • 2022
  • In this analysis, from the perspective of the business ecosystem, the economic effects of the oil and gas E&P industry were estimated. Australia, Norway, and the US, which are countries that are active in oil and gas E&P projects, and Japan and Korea, which are not, were analyzed. According to the analysis results, every country has a induced production coefficient of the oil and gas E&P industry greater than 1. Norway and the US have formed an industrial ecosystem across all industries, evenly demanding intermediate inputs for the primary, secondary, and tertiary industries. In contrast, Korea and Japan have a very large input ratio from the tertiary industry and an industrial ecosystem centered on the tertiary industry. It should be considered that the high input ratio of certain industry in business ecosystem determine the scale of the induced effect. When the business ecosystem are formed with many industries evenly, and the induced coefficient is high, it is necessary to increase the amount of final demand of the industry to make the effects of coefficient to increase.

6G Technology Competitiveness and Network Analysis: Focusing on GaN Integrated Circuit Patent Data (6G의 기술경쟁력 및 네트워크 분석: GaN 집적회로 특허 데이터 중심)

  • Woo-Seok Choi;Jin-Yong Kim;Jung-Hwan Lee;Sang-Hyun Choi
    • Journal of Industrial Convergence
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    • v.21 no.3
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    • pp.1-15
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    • 2023
  • Expectations for wireless communication technology are rising as a base technology that promotes innovation in various industries in line with the paradigm of digital transformation in the 21st century beyond the stage of being used only for communication service itself. In this study, in order to compare 6G technological competitiveness between Korea and leading countries, technological competitiveness was confirmed through PFS, CPP, and network analysis based on GaN Integrated Circuit patent data. Korea's 6G technological competitiveness was 0.62 in PFS and 3.93 in CPP, which were 32.8% and 19.9%, respectively, compared to leading countries. In addition, as a result of network analysis, the collaboration rate in the 6G field was 7.2%, and the collaboration ecosystem was very insufficient in most countries. In contrast, it was confirmed that Korea, unlike leading countries, has established a small-scale collaboration ecosystem linked by industry and academia. Thus, it is necessary to establish a strategy for 6G communication technology at the national level so that communication technology can be advanced based on a relatively well-established collaborative ecosystem.

The Effects of Spousal Bereavement and Complicated Grief on Death Anxiety among Older Adults (배우자 사별여부와 복잡성비애 수준이 노인의 죽음불안에 미치는 영향)

  • Kim, Kyung Hee;Lyu, Jiyoung
    • 한국노년학
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    • v.39 no.1
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    • pp.21-35
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    • 2019
  • The purpose of this study was to empirically verify the effects of spousal bereavement and complicated grief level on death anxiety of the elderly. The sample consisted of 1,998 adults who were aged 65 or older. Dependent variable was measured with the Death Anxiety Scale-Korean version (DAS-K). Independent variable was measured with both spousal bereavement and the Inventory of Complicated Grief-Korean version (ICG-K). Multiple regression analysis was performed using SPSS 23.0, adjusting for demographics, psycho-social and health variables. The results indicated that death anxiety level was lower among the bereaved with normal grief (p<.01) than non-bereaved. In contrast, death anxiety level was higher among the bereaved with complicated grief than non-bereaved (p<.01). The study result suggests that the most risky factor for death anxiety is complicated grief rather than the bereavement. Although the bereavement can be a universal experience, the severity and duration of symptoms after the bereavement may not be general. The unhealed emotional and physical pain after the bereavement stimulates death anxiety, and senior citizens who suffer from complicated grief often fail to integrate the bereavement and loss into reality, therefore, may not accept the death phenomenon itself. Anxiety and fear of death can emerge when they cannot acknowledge the bereavement. To manage complex sorrows and mitigate death anxiety, intervention programs should be provided to increase adaptability to the bereavement.