• KIISE Transactions on Computing Practices
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• v.21 no.11
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• pp.681-688
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• 2015

The k nearest neighbor (k-NN) graph construction is an important operation with many web-related applications, including collaborative filtering, similarity search, and many others in data mining and machine learning. Despite its many elegant properties, the brute force k-NN graph construction method has a computational complexity of $O(n^2)$, which is prohibitive for large scale data sets. Thus, (Key, Value)-based distributed framework, MapReduce, is gaining increasingly widespread use in Locality Sensitive Hashing which is efficient for high-dimension and sparse data. Based on the two-stage strategy, we engage the locality sensitive hashing technique to divide users into small subsets, and then calculate similarity between pairs in the small subsets using a brute force method on MapReduce. Specifically, generating a candidate group stage is important since brute-force calculation is performed in the following step. However, existing methods do not prevent large candidate groups. In this paper, we proposed an efficient algorithm for approximate k-NN graph construction by regrouping candidate groups. Experimental results show that our approach is more effective than existing methods in terms of graph accuracy and scan rate.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.12
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• pp.505-518
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• 2023

3D point cloud semantic segmentation is a computer vision task that involves dividing the point cloud into different objects and regions by predicting the class label of each point. Existing 3D semantic segmentation models have some limitations in performing sufficient fusion of multi-modal features while ensuring both characteristics of 2D visual features extracted from RGB images and 3D geometric features extracted from point cloud. Therefore, in this paper, we propose MMCA-Net, a novel 3D semantic segmentation model using 2D-3D multi-modal features. The proposed model effectively fuses two heterogeneous 2D visual features and 3D geometric features by using an intermediate fusion strategy and a multi-modal cross attention-based fusion operation. Also, the proposed model extracts context-rich 3D geometric features from input point cloud consisting of irregularly distributed points by adopting PTv2 as 3D geometric encoder. In this paper, we conducted both quantitative and qualitative experiments with the benchmark dataset, ScanNetv2 in order to analyze the performance of the proposed model. In terms of the metric mIoU, the proposed model showed a 9.2% performance improvement over the PTv2 model using only 3D geometric features, and a 12.12% performance improvement over the MVPNet model using 2D-3D multi-modal features. As a result, we proved the effectiveness and usefulness of the proposed model.

• Journal of Chest Surgery
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• v.28 no.11
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• pp.1014-1018
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• 1995

To confirm diagnosis and to set proper therapeutic strategy, open lung biopsies were done in 57 patients who were suspected for diffuse interstitial lung disease from January 1985 to December 1994. Among them, 35 were male and 22 were female[M:F=l.6: 1 and mean age of the patients is 53.5$\pm$ 2.3[24-81 years. Tissue for histologic studies were obtained from left lung in 33, from right lung in 24according to the distributions of the pathology. Preoperative diagnostic work-up`s were chest X-ray, CT[HRCT scan, sputum study, bronchoscopy[BAL, TBLB and PTNA and all of them were unsuccessful to confirm diagnosis. In comparison of pulmonary function tests between preoperative and postoperative values, there were no significant differences in FVC, FEV1, FEV1/FVC[p 0.05 but in AaDO2[p[0.05 . Postoperative complications including atelectasis, wound infection, pulmonary edema and respiratory insnfficiency, were shown in 5 cases[8.8% , and two of them were died of respiratory failure and sepsis[mortality rate 3.5% . Pathologic diagnosis was confirmed in 53 cases postoperatively but it was undetermined in 4[diagnostic yield rate 93.0% . In comparison between preoperative clinical diagnosis and postoperative pathologic diagnosis, new diagnosis were made in 17 cases[29.8% and preoperative tentative diagnosis were confirmed histologically in 36 cases[63.2% . In 4 cases[7.0% , however, diagnoses were not confirmed after biopsies. Therapeutic plans were reset in 46 cases[80.7% in accordance with the final diagnosis.In conclusion, open lung biopsy is recommended for a specific diagnosis and proper therapeutic plan in diffuse interstitial lung diseases because of its high diagnostic yield Irate and it`s relatively low morbidity and mortality rate in these tompromised patents.

• Proceedings of the Korea Database Society Conference
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• 2000.11a
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• pp.227-238
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• 2000

Firewall은 다양한 부정Access의 방지책으로서 확실히 유효한 수단이지만 이 Firewall은 사용자로부터 지시된 설정을 충실히 실행하는 것으로 설정 오류, 소프트웨어의 정지, 허가된 룰을 악용한 침입 등 반드시 사용자가 바라는 작용을 무조건적 상태에서 보증해 주는 것은 아니다. 따라서 사용자는 도입 후 에도 운용시에 Access log를 감시하고 본래의 Security Policy에 반하는 행위를 매일 매일 체크하지 않으면 안될 상황에 처해 있다. 본 연구는 이러한 부정Access에 대한 이와 같은 Firewall의 현상에 대한 과제 중에서 "부정Access를 어떻게 하면 일찍, 정확히 체크할 수 있는가\ulcorner"라는 주제를 선택하여 Firewall의 한계와 그 대응책을 실제로 부정Access를 시험해 보는 것으로 검증하기로 하였다. 실험결과에서 (1)Port Scan이나 전자메일 폭탄(서비스정지공격)등은 Firewall로 방지하는 것은 불가능하거나 혹은 Checking이 곤란하다. (2)공격마다 로그 수집을 했음에도 관계없이 Firewall의 로그는 번잡하므로 단시간에 사태의 발견이 대단히 곤란하다고 하는 Firewall의 한계를 인식하였다. 그리고 그 대책으로서 우리는 체크 툴의 유효성에 착안하여 조사한 결과, 결국 무엇이 부정Access인가에 대해서는 어디까지나 이용하는 측이 판단하여 Firewall 상에 설정하지 않으면 안되지만 체크 툴은 이 부정Access 정보를 데이터베이스로서 갖고 있음으로써 '무엇이 부정Access인가'를 이용자 대신에 판단하고 툴에 따라서는 설정을 자동적으로 변경하여 부정 Access의 저지율을 향상시킨다. 이처럼 체크 툴은 Firewall의 수비능력을 보강하는 위치에 있다고 생각할 수 있다.다. 4 장에서는 3장에서 제기한 각각의 문제점에 대해 RAD 의 관점에 비추어 e-business 시스템의 단기개발을 실현하기 위한 고려사항이나 조건 해결책을 제안한다. 본 논문이 지금부터 e-business 를 시작하려고 하는 분, e-business 시스템의 개발을 시작하려고 하는 분께 단기간의 e-business 실현을 위한 하나의 지침이 된다면 다행이겠다.formable template is used to optimize the matching. Then, clustering the similar shapes by the distance between each centroid, papaya can be completely detected from the background.uage ("Association of research for algorithm of calculating machine (1992)"). As a result, conventional NN and CNN were available for interpolation of sampling data. Moreover, when nonlinear intensity is not so large under the field condition of small slope, interpolation performance of CNN was a little not so better than NN. However, when nonlinear intensity is large under the field condition of large slope, interpolation performance of CNN was relatively better than NN.콩과 자연 콩이 성분 분석에서 차이를

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.3 s.162
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• pp.463-474
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• 2007

With rapid expansion in e-retailing of apparel business, personalized fitting model service shows the possibility as the differentiated marketing strategy in cyber shopping. According as necessity of personalized fitting model construction rises, it is tried personalized fitting model creation in several fields such as computer engineering, mechanical engineering, information engineering. But, because existent study was concentrated only on human body modeling, it does not reflect average morphological characteristics of human body properly. In this study, we wish to examine if morphing is fit for expressing characteristic of average human body shape and suggest desirable morphing. We used 3-D scan data of 254 Korean middle aged men collected by Size Korea 2004. The result of this study are as follows: Lower body types were categorized by height hip girth and lower drop(hip girth-navel girth) which were main factors of lower body shape. Then each factor was divided into 3 groups respectively, 30% in the middle, over 30%, under 30%. In 27 groups, the group which belonged to 30% in the middle of height, 30% in the middle of hip girth, 30% in the middle of lower drop was selected as a representative group. We tested geometrical figure by differ volume, tilt, position of point. And we created a representative type of men's lower bodies by morphing the representative group and analyzed it's horizontal, vertical sections. A representative type which was created by morphing reflected a real body and changed realistically at the part of hip, crotch, calf muscle and so on. A cross sections of a representative type were similar to average cross sections of the representative group in size and shape. So it was proved that morphing was successful.

• Allergy, Asthma & Respiratory Disease
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• v.6 no.6
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• pp.315-321
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• 2018

Purpose: Radiocontrast media are widely used in medical imaging to improve diagnostic accuracy. However, studies on the adverse reactions of radiocontrast media in children are limited. We aimed to describe the characteristics of adverse reactions to radiocontrast media among children who had a computed tomography scan or magnetic resonance imaging in a tertiary university hospital. Methods: We retrospectively collected data on adverse reactions to radiocontrast media by the reporting system of a tertiary university hospital. We selected data from children under the age of 19 from July 2011 to December 2017 and analyzed their characteristics. We focused mainly on the characteristics of the index case which is defined by the first adverse event of each subject. Results: During the period, a total of 88,050 radiocontrast media-enhanced imaging studies were performed and 184 cases of adverse reactions were reported. A total of 71 were identified as index cases. Forty-nine (69.0%) were male and the mean age was $12.7{\pm}3.2$ years. The incidence of radiocontrast media-related adverse reactions was 0.09% and severe reactions were 0.002%. The most common clinical feature was skin manifestations (54.9%), followed by gastrointestinal symptoms (40.8%) and neuropsychiatric symptoms (7.4%). Conclusion: Adverse reactions to radiocontrast media rarely occur in children and the incidence of severe reactions is low. Most reactions are mild and are related to the skin and gastrointestinal system. This report would provide good evidence for establishing a management strategy in children scheduled for imaging studies using radiocontrast media.

• Journal of Trauma and Injury
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• v.34 no.3
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• pp.191-197
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• 2021

Renal injuries occur in more than 10% of patients who sustain blunt abdominal injuries. Non-operative management (NOM) is the established treatment strategy for lowgrade (I-III) renal injuries. However, despite some evidence that NOM can be successfully applied to high-grade (IV, V) renal injuries, it remains unclear whether NOM is appropriate in such cases. The authors report two cases of high-grade renal injuries that underwent NOM after embolization in a hybrid emergency room (ER) system with a 24/7 in-house interventional radiology (IR) team. A 29-year-old male visited Wonkwang University Hospital Regional Trauma Center complaining of right abdominal pain after being hit by a rope. Computed tomography (CT) was performed 16 minutes after arrival, and the CT scan indicated a grade V right renal injury. Arterial embolization was initiated within 31 minutes of presentation. A 56-year-old male was transferred to Wonkwang University Hospital Regional Trauma Center with a complaint of right flank pain. He had initially presented to a nearby hospital after falling from a 3-m height. Thanks to the key CT images sent from the previous hospital prior to the patient's arrival, angiography was performed within 8 minutes of the patient's arrival and arterial embolization was completed within 25 minutes. Both patients were treated successfully through NOM with angioembolization and preserved kidneys. Hematoma in the first patient and urinoma in the second patient resolved with percutaneous catheter drainage. The authors believe that the hybrid ER system with an in-house IR team could contribute to NOM and kidney preservation even in high-grade renal injuries.

• Restorative Dentistry and Endodontics
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• v.44 no.3
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• pp.27.1-27.12
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• 2019

This case report describes a technique in which endodontic treatment and permanent indirect restoration were completed in the same clinical appointment with the aid of a computer-aided design/computer-aided manufacturing (CAD/CAM) system. Two patients were diagnosed with irreversible pulpitis of the mandibular first molar. After access preparation, root canals were located, irrigation was performed until bleeding ceased, and the coronal tooth structure was prepared for indirect restoration. Then, utilizing an interim 3-mm build-up of the endodontic access cavity, a hemi-arch digital scan was performed with an intraoral scanner. Subsequent to digital scanning, restoration design was performed simultaneously with the endodontic procedure. The root canals were shaped using the Race system under irrigation with 2.5% sodium hypochlorite followed by root canal filling. The pulp chamber was subsequently filled with a 3-mm-thick composite resin restoration mimicking the interim build-up previously utilized to facilitate block milling in the CAD/CAM system. Clinical try-in of the permanent onlay restoration was followed by acid etching, application of a 5th generation adhesive, and cementation of the indirect restoration. Once the restoration was cemented, rubber dam isolation was removed, followed by occlusal adjustment and polishing. After 2 years of follow-up, the restorations were esthetically and functionally satisfactory, without complications.

• The Journal of Advanced Prosthodontics
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• v.14 no.6
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• pp.369-378
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• 2022

PURPOSE. The purpose of this in vitro study was to assess whether scanning strategies of virtual interocclusal record (VIR) affect the accuracy of VIR during intraoral scanning. MATERIALS AND METHODS. Five pairs of reference cubes were added to the digital upper and lower dentitions of a volunteer, which were printed into resin casts. Subsequently, the resin casts were articulated in the maximal intercuspal position in a mechanical articulator and scanned with an industrial computed tomography system, of which the VIR was served as a reference VIR. The investigated VIR of the upper and lower jaws of the resin master cast were recorded with an intraoral scanner according to 9 designed scanning strategies. Then, the deviation between the investigated VIRs and reference VIR were analyzed, which were measured by the deviation of the distances of six selected reference points on the upper reference cubes in each digital cast to the XY-plane between the investigated VIRs and reference VIR. RESULTS. For the deviation in the right posterior dentitions, RP group (only scanning of right posterior dentitions) showed the smallest deviation. Besides, BP group (scanning of bilateral posterior dentitions) showed the smallest deviation in the left posterior dentitions. Moreover, LP group (scanning of left posterior dentitions) showed the smallest deviation in the anterior dentitions. For the deviation of full dental arches, BP group showed the smallest deviation. CONCLUSION. Different scanning strategies of VIR can influence the accuracy of alignment of virtual dental casts. Appropriate scanning strategies of VIR should be selected for different regions of interest and edentulous situations.

• Journal of Veterinary Science
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• v.23 no.5
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• pp.65.1-65.10
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• 2022

Background: Persistent uroliths after a cystotomy in dogs are a common cause of surgical failure. Objectives: This study examined the following: the success rate of retrograde urohydropropulsion in male dogs using non-enhanced computed tomography (CT), whether the CT mean beam attenuation values in Hounsfield Units (mHU) measured in vivo could predict the urolithiasis composition and whether the selected reconstruction kernel may influence the measured mHU. Methods: All dogs and cats that presented with lower urinary tract uroliths and had a non-enhanced CT preceding surgery were included. In male dogs, CT was performed after retrograde urohydropropulsion to detect the remaining urethral calculi. The percentage and location of persistent calculi were recorded. The images were reconstructed using three kernels, from smooth to ultrasharp, and the calculi mHU were measured. Results: Sixty-five patients were included in the study. The success rate of retrograde urohydropropulsion in the 45 male dogs was 55.6% and 86.7% at the first and second attempts, respectively. The predominant components of the calculi were cystine (20), struvite (15), calcium oxalate (8), and urate (7). The convolution kernel influenced the mHU values (p < 0.05). The difference in mHU regarding the calculus composition was better assessed using the smoother kernel. A mHU greater than 1,000 HU was predictive of calcium oxalate calculi. Conclusions: Non-enhanced CT is useful for controlling the success of retrograde urohydropropulsion. The mHU could allow a prediction of the calculus composition, particularly for calcium oxalate, which may help determine the therapeutic strategy.