• Title/Summary/Keyword: length scales

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Geometric Regualrization of Irregular Building Polygons: A Comparative Study

  • Sohn, Gun-Ho;Jwa, Yoon-Seok;Tao, Vincent;Cho, Woo-Sug
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.25 no.6_1
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    • pp.545-555
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    • 2007
  • 3D buildings are the most prominent feature comprising urban scene. A few of mega-cities in the globe are virtually reconstructed in photo-realistic 3D models, which becomes accessible by the public through the state-of-the-art online mapping services. A lot of research efforts have been made to develop automatic reconstruction technique of large-scale 3D building models from remotely sensed data. However, existing methods still produce irregular building polygons due to errors induced partly by uncalibrated sensor system, scene complexity and partly inappropriate sensor resolution to observed object scales. Thus, a geometric regularization technique is urgently required to rectify such irregular building polygons that are quickly captured from low sensory data. This paper aims to develop a new method for regularizing noise building outlines extracted from airborne LiDAR data, and to evaluate its performance in comparison with existing methods. These include Douglas-Peucker's polyline simplication, total least-squared adjustment, model hypothesis-verification, and rule-based rectification. Based on Minimum Description Length (MDL) principal, a new objective function, Geometric Minimum Description Length (GMDL), to regularize geometric noises is introduced to enhance the repetition of identical line directionality, regular angle transition and to minimize the number of vertices used. After generating hypothetical regularized models, a global optimum of the geometric regularity is achieved by verifying the entire solution space. A comparative evaluation of the proposed geometric regulator is conducted using both simulated and real building vectors with various levels of noise. The results show that the GMDL outperforms the selected existing algorithms at the most of noise levels.

A Variable-Length FFT/IFFT Processor for Multi-standard OFDM Systems (다중표준 OFDM 시스템용 가변길이 FFT/IFFT 프로세서)

  • Yeem, Chang-Wan;Shin, Kyung-Wook
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.2A
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    • pp.209-215
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    • 2010
  • This paper describes a design of variable-length FFT/IFFT processor (VL_FCore) for OFDM-based multi-standard communication systems. The VL_FCore adopts in-place single-memory architecture, and uses a hybrid structure of radix-4 and radix-2 DIF algorithms to accommodate various FFT lengths in the range of $N=64{\times}2^k\;(0{\leq}k{\leq}7)$. To achieve both memory size reduction and the improved SQNR, a two-step conditional scaling technique is devised, which conditionally scales the intermediate results of each computational stage. The performance analysis results show that the average SQNR's of 64~8,192-point FFT's are over 60-dB. The VL_FCore synthesized with a $0.35-{\mu}m$ CMOS cell library has 23,000 gates and 32 Kbytes memory, and it can operate with 75-MHz@3.3-V clock. The 64-point and 8,192-point FFT's can be computed in $2.25-{\mu}s$ and $762.7-{\mu}s$, respectively, thus it satisfies the specifications of various OFDM-based systems.

Body Characteristics, Perceived Body Size and Body-Cathexis for Short Women Aged 18 to 59 (18~59세 키 작은 여성의 체형특징, 신체인식과 신체만족도 분석)

  • Lee, Jeong-Yim
    • Journal of the Korean Society of Clothing and Textiles
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    • v.35 no.11
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    • pp.1346-1361
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    • 2011
  • This study examined the body characteristics, perceived body size and body-cathexis according to the stature of women aged 18 to 59. Special focus was on women of short stature; in addition, the study searched for the proper clothing fit and satisfaction level for short women. The 2010 SizeKorea data of 2,586 women aged 18 to 59 was analyzed statistically to find the distribution of stature according to 4 age groups along with the body characteristics and proportion of 3 stature groups in each age group. A questionnaire was conducted with responses from 412 women aged 18 to 59, and the perceived body size and satisfaction with body size of 3 stature groups were studied with 5 Likert scales. Although the stature of Korean women has increased, short stature women (those under 155cm) still represent a high percentage of individuals in Korea. Short women (small in height and length) had unique body characteristics in width, depth, and girth that were distinguished from the characteristics of medium or tall women. Especially, the lower body part of short women had distinct characteristics. Accordingly, it is undesirable to reflect the same ease or same body proportion in clothing construction for the 3 stature groups. Short women perceived their stature and length of upper or lower body as too short and the satisfaction with their body size was lower than medium or tall women. To upgrade the clothing fit and satisfaction of short women, it is necessary to reflect the unique body characteristics of short women in clothing design and construction.

A study on the visual image of men's suit (남성 정장 수트의 시각적 이미지에 관한 연구)

  • Kim, Jeong-Mee
    • Journal of the Korea Fashion and Costume Design Association
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    • v.23 no.1
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    • pp.113-127
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    • 2021
  • This study aims to analyze the style of men's suits and extract expressional words for the development of semantic differential scales of visual images according to the change in silhouette. Research methods are literature studies, case studies, and questionnaires. The stimuli were created using CLO 3D, a virtual sewing CAD. This study's results are as follows: 1) The British suit jacket has an angled shoulder line using thin pads, and a slightly higher waistline. The pants of the suit have a high waistline and two pleats, so the thighs of the pants are wide. The American suit jacket has a natural shoulder line, and the waistline is not emphasized. The width of the jacket is relaxed, and the length is long. The pants of the suit have a higher waistline, and the pants are wide as well. The Italian suit jacket has wide shoulders, and the waistline is connected lower with a soft curve, and the length is relatively short. The trousers of the suit are tapered and get narrower as it goes down to the hem. 2) Because it originated in the practices of true bespoke tailoring, traditional British suits have a far more 'fitted' silhouette than the mass-produced styles that became emblematic of the American style. By the late 1950s, a sack-style suit was standard American business attire. This technique gives the sack suit its characteristically 'boxy' silhouette. The "Continental" presented a highly tailored silhouette, with padded shoulders, a slim, tight-fitting chest, and a closely tapered waist. The story was that Italian culture valued aesthetics over all else and thus sought the 'slim' suit style as much as possible. 3) The main expressional words of visual images for men's suits differ greatly depending on the silhouette of suit. The visual images are ranked in the order of 'neat', 'classic', 'educated', 'hard', 'mature', for fitted silhouettes. The words of 'masculine', 'basic', 'comfortable', 'simple', 'mature', 'conservative', 'modern', are ranked for boxy silhouettes. And the words of 'slim', 'young', 'neat', are noted for slim silhouettes.

Factors Related to Workload of Intensive Care Unit Nurses: Systematic Review and Meta-Analysis (중환자실 간호사의 업무부담 관련 요인: 체계적 문헌고찰 및 메타분석)

  • Jeong, Ah In;Shin, Sujin;Hong, Eunmin
    • Journal of Korean Clinical Nursing Research
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    • v.29 no.3
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    • pp.296-311
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    • 2023
  • Purpose: This study aimed to identify factors related to the workload of intensive care unit nurses through a systematic literature review and meta-analysis to provide basic data to explore the direction of development of nursing staffing standards. Methods: This study involved quantitative studies about nurses working in intensive care units related to nursing workload published in English or Korean since 2000. Search terms included 'intensive care unit', 'nursing workload', and their variations. Databases such as RISS, DBpia, MEDLINE(PubMed), CINAHL, PsycINFO, and Web of Science were utilized. Quality assessment was conducted using the Joanna Briggs Institute's Critical Appraisal Checklist for Analytical Cross-Sectional Studies. JAMOVI software facilitated the analysis of effect sizes, employing a meta-analysis approach for 7 studies with correlational or regression data. Results: From 16 studies on the workload of intensive care unit nurses, a total of 20 patient and nurse-related factors were identified. Patient-related factors included severity of illness, length of stay, and age. Meta-analysis was conducted for three patient-related factors: age, severity of illness measured by SAPS 3, and length of stay. Only severity of illness measured by SAPS 3 was significantly associated with nurse workload (Zr=0.16, p<.001, 95% CI=0.09-0.24). Conclusion: In previous studies, the characteristics of intensive care units and patients varied across studies, and a variety of scales for measuring workload and severity of illness were also used. Sustained research reflecting domestic intensive care unit work environments and assessing the workload of intensive care unit nurses should be imperative.

Occurrence of a Natural Interspecific Hybrid between Rhodeus pseudosericeus and R. notatus in Sangcheon Stream of the Han River, Korea (한강수계 상천천에서 한강납줄개 Rhodeus pseudosericeus와 떡납줄갱이 R. notatus의 종간 자연잡종 출현)

  • Kwak, Yeong-Ho;Kim, Keun-Yong;Kim, Keun-Sik;Song, Ha-Yun
    • Korean Journal of Ecology and Environment
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    • v.53 no.3
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    • pp.275-285
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    • 2020
  • Two specimens presumed to be hybrids of Rhodeus pseudosericeus and R. notatus were collected from the Sangcheon Stream of the Han River, Korea. The body color of natural hybrid individuals was yellowish brown, showing the intermediate characteristics of R. pseudosericeus and R. notatus, but overall, the characteristics of R. notatus were similar. Meristic and morphometric characters, the number of dorsal fin rays, anal fin rays and longitudinal row scales showed a hybrid index (HI) of 0, indicating the characters of R. notatus. The hybrid index of predorsal length (HI=74.6), preanal length (HI=75.3), and preventral length (HI=77.6) were similar to the characters of the R. pseudosericeus. Also four characters were appeared to have intermediate characters between R. pseudosericeus and R. notatus; number of gill rakers (HI=55.3), body depth (HI=67.9), snout length (HI=43.4), and inter orbital width (HI=44.8). The rest of 14 characters deviated between 0 and 100, showing unique characteristics of hybrid individuals. Recombination activating gene 1 (RAG1) analysis, hybrids were identified as natural hybrids due to the overlapping peaks of their parent species. Also, as a result of analysis using the cytochrome b gene (COB), one individual was derived from R. pseudosericeus, while the other was derived from R. notatus.

Changes of Drainage Paths Length and Characteristic Velocities in Accordance with Spatial Resolutions (공간해상도에 따른 배수경로길이 및 특성유속의 변화)

  • Choi, Yong-Joon;Kim, Joo-Cheol
    • Journal of Korean Society for Geospatial Information Science
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    • v.19 no.3
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    • pp.107-114
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    • 2011
  • In this study, when interpreting leakage using the concept of geographical dispersion based on grid, to choose an appropriate spatial resolution, the statistical characteristics of drainage path length and the pattern of change of hydrodynamic parameters have been observed. Drainage path length has been calculated using an 8-direction algorithm from digital elevation model, from which the hydrodynamic parameters of the watershed were estimated. The scales of topographical map for this analysis are 1:5,000 and 1:25,000, appling grid sizes 5, 10, 15, 20 m and 20, 30, 50, 100, 150, 200 m, respectively. As results of this analysis, depending on the scale of stream networks, the statistical characteristics of drainage path length by spatial resolution and hydrodynamic parameters of the watershed have been changed. Based on the above results, when interpreting leakage using the concept of the geographical dispersion based on grid, in the case of 1:5,000 scale topographical map, a spatial resolution of 5 m will be better showing geographical and hydrodynamic characteristics to apply to the well developed stream network in basins, spatial resolution of 5~20 m to the less developed stream network in basins. And in the case of 1:25,000 scale topographical map, spatial resolution below 50 m is more desirable to show above two characteristics to apply to both cases.

Early Life History of Tanakia latimarginata (낙동납자루(Tanakia latimarginata)의 초기생활사)

  • Park, Jae-Min;Jeon, Hyung-Bae;Jo, Hye-In;Cho, Seong-Jang;Suk, Ho-Young;Han, Kyeong-Ho
    • Korean Journal of Ichthyology
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    • v.30 no.2
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    • pp.75-83
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    • 2018
  • This study is to observe species identification and early life history of Korean endemic species of Tanakia latimarginata and to use it as a basis for taxonomic studies. As a result of morphological identification, a dark band appeared at the margin of the anal fin, and the ovipositor color of the female was light orange. The shape of the egg was fusiform and sticky. The egg size (long${\times}$short diameter) averaged $4.41{\times}1.44mm$. The incubation time was 126 hours after the fertilization at an average water temperature of $21.0^{\circ}C$. Immediately after hatching, the larvae had egg yolk at an average total length of $5.91{\pm}0.18mm$ (n=5). At 18 days after hatching, the trunk fur was developed in the caudal fin with an average total length of $8.02{\pm}0.08mm$ (n=5). At 41 days after hatching, the larvae absorbed egg yolk at an average total length of $8.70{\pm}0.23mm$ (n=5). At 80 days after hatching, the average length of the fins was $12.6{\pm}0.28mm$ (n=5). The number of fin of the dorsal fin was iii.8, the anal fin iii.9~10, the caudal fin 19, lateral line scales 32~35 were similar to their brood stork.

Capillary Assembly of Silicon Nanowires Using the Removable Topographical Patterns

  • Hong, Juree;Lee, Seulah;Lee, Sanggeun;Seo, Jungmok;Lee, Taeyoon
    • Korean Journal of Materials Research
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    • v.24 no.10
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    • pp.509-514
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    • 2014
  • We demonstrate a simple and effective method to accurately position silicon nanowires (Si NWs) at desirable locations using drop-casting of Si NW inks; this process is suitable for applications in nanoelectronics or nanophotonics. Si NWs were assembled into a lithographically patterned sacrificial photoresist (PR) template by means of capillary interactions at the solution interface. In this process, we varied the type of solvent of the SiNW-containing solution to investigate different assembly behaviors of Si NWs in different solvents. It was found that the assembly of Si NWs was strongly dependent on the surface energy of the solvents, which leads to different evaporation modes of the Si NW solution. After Si NW assembly, the PR template was cleanly removed by thermal decomposition or chemical dissolution and the Si NWs were transferred onto the underlying substrate, preserving its position without any damage. This method enables the precise control necessary to produce highly integrated NW assemblies on all length scales since assembly template is easily fabricated with top-down lithography and removed in a simple process after bottom-up drop-casting of NWs.

Fractal Approach to Alternating Current Impedance Spectroscopy Studies of Carbon Nanotubes/Epoxy Polymer Composites

  • Belhimria, Rajae;Boukheir, Sofia;Samir, Zineb;Len, Adel;Achour, Mohammed Essaid;Eber, Nandor;Costa, Luis Cadillon;Oueriagli, Amane
    • Applied Microscopy
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    • v.47 no.3
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    • pp.126-130
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    • 2017
  • The dielectric relaxation characteristics of composites with different concentrations of carbon nanotubes loaded in an epoxy polymer matrix has been studied as a function of frequency over a wide range (1 Hz~10 MHz) at room temperature. Two characterization techniques were used in this work to measure and calculate the dimensionality parameters: small angle neutron scattering and impedance spectroscopy. The results obtained from both methods are in good agreement, indicating the reliability of the estimated fractal dimension, despite of the difference in the length scales accessed by the two techniques.