• Clinical and Experimental Vaccine Research
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• v.12 no.4
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• pp.265-290
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• 2023

Rare but serious thrombotic incidents in relation to thrombocytopenia, termed vaccine-induced immune thrombotic thrombocytopenia (VITT), have been observed since the vaccine rollout, particularly among replication-defective adenoviral vector-based severe acute respiratory syndrome coronavirus 2 vaccine recipients. Herein, we comprehensively reviewed and summarized reported studies of VITT following the coronavirus disease 2019 (COVID-19) vaccination to determine its prevalence, clinical characteristics, as well as its management. A literature search up to October 1, 2021 using PubMed and SCOPUS identified a combined total of 720 articles. Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guideline, after screening the titles and abstracts based on the eligibility criteria, the remaining 47 full-text articles were assessed for eligibility and 29 studies were included. Findings revealed that VITT cases are strongly related to viral vector-based vaccines, which are the AstraZeneca COVID-19 vaccine (95%) and the Janssen COVID-19 vaccine (4%), with much rarer reports involving messenger RNA-based vaccines such as the Moderna COVID-19 vaccine (0.2%) and the Pfizer COVID-19 vaccine (0.2%). The most severe manifestation of VITT is cerebral venous sinus thrombosis with 317 cases (70.4%) and the earliest primary symptom in the majority of cases is headache. Intravenous immunoglobulin and non-heparin anticoagulant are the main therapeutic options for managing immune responses and thrombosis, respectively. As there is emerging knowledge on and refinement of the published guidelines regarding VITT, this review may assist the medical communities in early VITT recognition, understanding the clinical presentations, diagnostic criteria as well as its management, offering a window of opportunity to VITT patients. Further larger sample size trials could further elucidate the link and safety profile.

• Journal of Intelligence and Information Systems
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• v.26 no.1
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• pp.1-21
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• 2020

With the rapid development of artificial intelligence technology, various techniques have been developed to extract meaningful information from unstructured text data which constitutes a large portion of big data. Over the past decades, text mining technologies have been utilized in various industries for practical applications. In the field of business intelligence, it has been employed to discover new market and/or technology opportunities and support rational decision making of business participants. The market information such as market size, market growth rate, and market share is essential for setting companies' business strategies. There has been a continuous demand in various fields for specific product level-market information. However, the information has been generally provided at industry level or broad categories based on classification standards, making it difficult to obtain specific and proper information. In this regard, we propose a new methodology that can estimate the market sizes of product groups at more detailed levels than that of previously offered. We applied Word2Vec algorithm, a neural network based semantic word embedding model, to enable automatic market size estimation from individual companies' product information in a bottom-up manner. The overall process is as follows: First, the data related to product information is collected, refined, and restructured into suitable form for applying Word2Vec model. Next, the preprocessed data is embedded into vector space by Word2Vec and then the product groups are derived by extracting similar products names based on cosine similarity calculation. Finally, the sales data on the extracted products is summated to estimate the market size of the product groups. As an experimental data, text data of product names from Statistics Korea's microdata (345,103 cases) were mapped in multidimensional vector space by Word2Vec training. We performed parameters optimization for training and then applied vector dimension of 300 and window size of 15 as optimized parameters for further experiments. We employed index words of Korean Standard Industry Classification (KSIC) as a product name dataset to more efficiently cluster product groups. The product names which are similar to KSIC indexes were extracted based on cosine similarity. The market size of extracted products as one product category was calculated from individual companies' sales data. The market sizes of 11,654 specific product lines were automatically estimated by the proposed model. For the performance verification, the results were compared with actual market size of some items. The Pearson's correlation coefficient was 0.513. Our approach has several advantages differing from the previous studies. First, text mining and machine learning techniques were applied for the first time on market size estimation, overcoming the limitations of traditional sampling based- or multiple assumption required-methods. In addition, the level of market category can be easily and efficiently adjusted according to the purpose of information use by changing cosine similarity threshold. Furthermore, it has a high potential of practical applications since it can resolve unmet needs for detailed market size information in public and private sectors. Specifically, it can be utilized in technology evaluation and technology commercialization support program conducted by governmental institutions, as well as business strategies consulting and market analysis report publishing by private firms. The limitation of our study is that the presented model needs to be improved in terms of accuracy and reliability. The semantic-based word embedding module can be advanced by giving a proper order in the preprocessed dataset or by combining another algorithm such as Jaccard similarity with Word2Vec. Also, the methods of product group clustering can be changed to other types of unsupervised machine learning algorithm. Our group is currently working on subsequent studies and we expect that it can further improve the performance of the conceptually proposed basic model in this study.

• Korean Journal of Environmental Agriculture
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• v.23 no.2
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• pp.111-116
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• 2004

Salt occlusion in Zeolite is a unique phenomenon that takes place only when the salt size is similar to the window size of host zeolite. $KCIO_3$-occluded Zeolite, as an environment-friendly oxidant, has a high potential for effective removal of various organic pollutants. This study was carried to investigate the characteristics and the removal kinetics of fungicide chlorothalonil by zeolite-$KCIO_3$ complex. About 10% of $KCIO_3$ was occluded in zeolite pores synthesized by salt-thermal method from fly ash, although the occlusion amount was relatively less compared to that of nitrate salts. By occlusion with $KCIO_3$, no remarkable changes were found in X-ray diffraction patterns of cancrinite, whereas some decrease of overall peak intensities was found with those of sodalite. Different releasing kinetics of $CIO_3^-$ ion were observed in distilled water and soil solution from zeolite-$KCIO_3$ complex. Two reactions, hydration and diffusion, seem to be related with the release of $KCIO_3$. Therefore, the release isotherm of $CIO_3^-$ ion well fitted to the power function model which indicate the release was made by hydration and diffusion. The removal of chlorothalonil by zeolite and $KCIO_3$ reached at reaction equilibrium within 6 hours by 18% and 47% respectively. However, the chlorothalonil removal by the zeolite-$KCIO_3$ complex increased slowly and steadily up to 92% in 96 hours. These findings suggested that zeolite-$KCIO_3$ complex could be applied for effective removal of organic contaminants in the soil and aqueous environment.

• Korean Institute of Interior Design Journal
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• v.20 no.1
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• pp.154-164
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• 2011

The purpose of this study is to identify more types of residents in medium-sized apartments in Seoul by lifestyle that has been used as a variable of space planning and to investigate and present bathroom design appropriate for characteristics of each resident type. The article examines the general characteristics, lifestyle types, and preference for the bathroom design. A total of 642 samples, acquired via internet survey, were analyzed with the statistical computer program SPSS PC+ window version 16.0. The conclusion of the article are as follows: 1) The lifestyle of users living in medium-sized apartments are categorized into 4 types: trend seeking, aesthetic seeking, family seeking, information seeking types. 2) The preference for the bathroom design of trend seeking type, the toilet is a bidet-builtin type and the washstand is a semi-counter type and the bathtub is a spa type and the shower booth is a bathtub-extending type. The storage closet is a upper-fixed type with two sides, the finishing materials are tiles and PVC monorium, and light built in a wall. 3) The preference for the bathroom design of aesthetic seeking type, the toilet is a bidet-builtin type and the washstand is a semi-counter type and the bathtub is a whirlpool type and the shower booth is a steam-sauna type. The storage closet is a upper-fixed with one side and opened closet, the finishing materials are tiles. 4) The preference for the bathroom design of family seeking type, the toilet is a bidet-builtin type and the washstand is a stand type and the bathtub is a reclamation type and the shower booth is a partition type. The storage closet is a upper-fixed with three sides. 5) The preference for the bathroom design of information seeking type, the toilet is a bidet-builtin type and the washstand is a semi-counter and the bathtub is a spa type and the shower booth is a partition type. The storage closet is a upper-fixed type with two sides. The results of this study may be used as basic data in planning bathroom design for housing supply for housing suppliers, and used as significant information for residents to identify their own types that can be referred when they select apartments to live in.

• The korean journal of orthodontics
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• v.35 no.5 s.112
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• pp.388-397
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• 2005

The purpose of this study was to redefine the cephalometric landmarks in three-dimensional (3D) images, which are used in orthodontic cephalometric radiography, and to evaluate the reproducibility of each landmark for 3D cephalometric analysis. Eighteen CT scans were taken at the Department of Diagnostic Radiology at Seoul National University Dental Hospital and manipulated with V works 4.0(Cybermed Inc., Seoul, Korea). The coordinate system was established using 7 reference points, with no more than 4 points on the same plane. These 7 points were generated as a volume model, the voxel size of which was 4 by 4 by 2 (threshold value=639). The cephalometric landmarks were selected at the multiplanar reformation (MPR) window on the volume mode of V works 4.0. The selected landmarks were exported to V surgery (Cybermed Inc., Seoul, Korea) for the calculation of coordinate values. All the data were taken twice with a lapse of 2 weeks by one investigator The reproducibility of each landmark was $0.17\~1.21mm$ in the x axis, $0.30\~1.53mm$. In the y axis, and $0.27\~1.81mm$ in the z axis. In all three axes, the range of error was similar. These error ranges were acceptable with regards to the pixel space and slice thickness. The most reproducible points were 1 points which were selected on the basis of the volume model. The least reproducible points were J points that were defined by sutures.

• Journal of the Korean Geophysical Society
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• v.10 no.1
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• pp.1-12
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• 2007

A method to quickly estimate broadband moment magnitudes (Mwp) to warn regional and teleseismic tsunamigenic earthquakes is tested for application of the method to the different seismic observation environment. In this study, the Mwp is calculated by integrating far-field P-wave or pP-wave of vertical component of displacement seismograms in time domain from earthquakes, having magnitude greater than 5.0 and occurred in and around the Korean peninsula from 2000 to 2006. We carefully set up the size of the time window for the computations to exclude S wave phases and other phases following after the P wave phase. The P wave velocities and the densities from the averaged Korean crustal model are used in the computations. Instrumental correction was performed to remove dependency on the seismograph. The Mwp after the instrumental correction is about 0.1 greater than the Mwp before the correction. The comparison of our results to the those of foreign agencies such as JMA and Havard CMT catalogues shows a higher degree of similarity. Thus our results provide an effective tool to estimate the earthquake size, as well as to issue the necessary information to a tsunami warning system when the effective earthquake occurs around the peninsula.

• Radiation Oncology Journal
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• v.15 no.4
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• pp.393-402
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• 1997

Purpose : When an x-ray beam of small field size is irradiated to target area containing an air cavity, such as larynx, the underdosing effect is observed in the region near the interfaces of air and soft tissue. With a larynx model, air cavity embedded in tissue-equivalent material, this study is intonded for examining Parameters, such as beam quality, field size, and cavity size, to affect the dose distribution near the air cavity. Materials and Methods : Three x-rar beams, 4-, 6- and 10-MV, were employed to Perform a measurement using a 2cm $(width){\times}L$ (length in cm, one side of x-ray field used 2cm (height) air cavity in the simulated larynx. A thin window parallel-plate chamber connected to an electrometer was used for a dosimetry system. A ratio of the dose at various distances from the cavity-tissue interface to the dose at the same points in a homogeneous Phantom (ebservedlexpected ratio, O/E) normalized buildup curves, and ratio of distal surface dose to dose at the maximum buildup depth were examined for various field sizes. Measurement for cavity size effect was performed by varying the height (Z) of the air cavity with the width kept constant for several field sizes. Results : No underdosing effect for 4-MV beam for fields larger than $5cm\times5cm$ was found For both 6- and 10-MV beams, the underdosing portion of the larynx at the distal surface was seen to occur for small fields, $4cm\times4cm\;and\;5cm\times5cm$. The underdosed tissue was increased in its volume with beam energy even for similar surface doses. The relative distal surface dose to maximum dose was changed to 0.99 from 0.95, 0.92, and 0.91 for 4-, 6-, and 10-MV, respectively, with increasing field size, $4cm\times4cm\;to\;8cm\times8cm$, For 6- and 10-MV beams, the dose at the surface of the cavity is measured less than the predicted by about two and three percent. respectively. but decrease was found for 4-MV beam for $5cm\times5cm$ field. For the $4cm\timesL\timesZ$ (height in cm). varying depth from 0.0 to 4.8cm, cavity, O/E> 1.0 was observed regardless of the cavity size for any field larger than about $8cm\times8cm$. Conclusion : The magnitude of underdosing depends on beam energy, field size. and cavity size for the larynx model. Based on the result of the study. caution must be used when a small field of a high quality x-ray beam is irradiated to regions including air cavities. and especially the region where the tumor extends to the surface. Low quality beam. such as. 4-MV x-ray, and larger fields can be used preferably to reduce the risk of underdosing, local failure. In the case of high quality beams such as 6- and 10-MV x-rays, however. an additional boost field is recommended to add for the compensation of the underdosing region when a typically used treatment field. $8cm\times8cm$, is employed.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.17.2-19
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• 1982

The sinus tympani is subject to great variability in the size, shape and posterior extent. A heavy compact bony zone, especially in the posterior portion and the narrow space between the facial nerve and posterior semicircular canal are the limitation of surgical approach. The facial recess should be opened, creating a wide connection between the mesotympanum and mastoid in the Intact canal wall tympanoplasty with mastoidectomy. The surgically created limits of the facial recess are the facial nerve medially, the chorda tympani laterally and the bone adjacent to the incus superiorly. Using adult Korean's thirty-five temporal bones, the authors measured the osteologic reslationship in the posterior tympanum, especially sinus tympani and facial recess. The result was as followed. 1. The average distance from the anterior end of the pyramidal eminence. 1) to the edge of the sinus tympani directly posterior was 2.54(1.05-5.40)mm. 2) to the maximum posterior extent was 3.22(1.25-7.45)mm. 3) to the maximum cephaled extent was 0.67 (0.40-1.75)mm. 2. The boundary of the sinus tympani was 82.9% from the lower margin oval window to the upper margin round window niche. 3. The deepest part of the sinus tympani was 62.9% in the mid portion, between the ponticulus and subiculum. 4. The oblique dimension from the fossa incudis above to the hypotympanum below was 8.13(7.90-9.55)mm. 5. The transverse dimensions midway between the oval window above and round window below was 3.00(2.85-3.45)mm. 6. The transverse dimension at the level of the fossa incudis was 1.81(1.40-2.15)mm. 7. The facial nerve dehiscence was 14.3%. 8. Anterior-posterior diameter of the footplate was 2.98(2.85-3.05) mm. 9. The average distance from the footplate. 1) to the cochleariform process was 1.42(1.35-1.55) mm. 2) to the round window niche was 1.85(1.45-2.10) mm.

• The Journal of Korean Society for Radiation Therapy
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• v.25 no.2
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• pp.145-151
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• 2013

Purpose: In this study, we analyzed how the dose change by field size effects on atomic number of shielding materials while using 6 MeV election beam. Materials and Methods: The parallel plate chamber is mounted in $25{\times}25cm^2$ the phantom such that the entrance window of the detector is flush with the phantom surface. phantom was covered laterally with aluminum, copper and lead which thickness have 5% of allowable transmission and then the doses were measured in field size $6{\times}6$, $10{\times}10$ and $20{\times}20cm^2$ respectively. 100 cGy was irradiated using 6 MeV electron beam and SSD (Source Surface Distance) was 100 cm with $10{\times}10cm^2$ field size. To calculate the photon flux, electron flux and Energy deposition produced after pass materals respectively, MCNPX code was used. Results: The results according to the various shielding materials which have 5% of allowable transmission are as in the following. Thickness change rate with field size of $6{\times}6cm^2$ and $20{\times}20cm^2$ that compared to the field size of $10{\times}10cm^2$ found to be +0.06% and -0.06% with aluminum, +0.13% and -0.1% with copper, -1.53% and +1.92% with lead respectively. Compare to the field size $10{\times}10cm^2$, energy deposition for $6{\times}6cm^2$ and $20{\times}20cm^2$ had -4.3% and +4.85% respectively without shielding material. With aluminum it had -0.87% and +6.93% respectively and with lead it had -4.16% and +5.57% respectively. When it comes to photon flux with $6{\times}6cm^2$ and $20{\times}20cm^2$ of field sizes the chance -8.95% and +15.92% without shielding material respectively, with aluminum the number -15.56% and +16.06% respectively and with copper the chance -12.27% and +15.53% respectively, with lead the number +12.36% and -19.81% respectively. In case of electron flux in the same condition, the number -3.92% and +4.55% respectively without shielding material respectively, with aluminum the number +0.59% and +6.87% respectively, with copper the number -1.59% and +3.86% respectively, with lead the chance -5.15% and +4.00% respectively. Conclusion: In this study, we found that the required thickness of the shielding materials got thinner with low atomic number substance as the irradiation field is increasing. On the other hand, with high atomic number substance the required thickness had increased. In addition, bremsstrahlung radiation have an influence on low atomic number materials and high atomic number materials are effected by scattered electrons.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.63-72
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• 2012

In contemporary times, "environmental designers" need to consider both exterior and interior aspects because of the growing trend in dissolution between exterior and interior spaces. To quantify "spatial sense" which serves as the standard for environmental design, this study has asked 63 subjects to evaluate 15 interior and 14 exterior spaces. The "spaciousness (small-large)", "openness(closed-open)", "warmness(warm-cold)", "brightness(bright-dark)", "softness(soft-hard)", "spatial intimacy" and "frequency of visit" were adopted as variables of spatial sense. Through the analysis of these variables, this study could gain the difference between spatial sense for exterior and interior environments, quantify the spatial sense that physically and psychologically appropriates to human beings. The result of this study can be summarized as follows: Twice the amount of spaciousness was observed between the interior and exterior spaces. And the standard on intimate space is established with W/H ratio of 5.71 and high Window/Wall Area ratio in the interior and an area of 3,800m2 and a W/H ratio of 5.57 in exterior. The difference between the spatial sense in the interior and exterior space is mostly dependent on the psychological sense. The increase of physical size caused by the interior space to be perceived as cold, dark and hard psychologically, but exterior space to be perceived as warm, bright and soft. Psychological senses, especially softness, affect spatial intimacy to the greatest extent among the given variables. As the psychological senses for interior spaces were largely independent from the given space's size and perceptive senses, the size of the interior space, which exhibited spatial intimacy, could not be deduced. In comparison to this, due to the high dependency between the psychological senses for exterior spaces and the given space's size and perceptive senses. The study also showed that interior and exterior spaces have relatively different spatial sense and physical standards. Such research results are predicted to provide applicable standards for environmental designers for exterior and interior spaces in the future.