• Tunnel and Underground Space
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• v.31 no.4
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• pp.211-220
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• 2021

Tunnel collapse often occurs during deep underground tunneling (> 40 m depth) in South Korea. Natural cavities as well as water supply pipes, sewer pipes, electric power cables, artificial cavities created by subway construction are complexly distributed in the artificial ground in the shallow depths of the urban area. For deep tunnel excavation, it is necessary to understand the properties of the ground which is characterized by porous elements and various geological structures, and their influence on the stability of the ground. This study analyzed geological factors for risk assessment in deep excavation in South Korea based on domestic and overseas case study. As a result, a total of 7 categories and 38 factors were derived. Factors with high weights were fault and fault clay, differential stress, rock type, groundwater and mud inrush, uniaxial compressive strength, cross-sectional area of tunnel, overburden thickness, karst and valley terrain, fold, limestone alternation, fluctuation of groundwater table, tunnel depth, dyke, RQD, joint characteristics, anisotropy, rockburst and so forth.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.1
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• pp.91-99
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• 2022

Severely worn dentition causes various complications such as loss of tooth structure, discoloration, pulp complications and loss of function and aesthetics. In this case, the patient showed particularly severe attrition in the anterior teeth and lack of space for restoration. The amount of vertical dimension was determined based on the diagnostic wax up, and the patient's adaptation was evaluated by using a removable occlusal splint for 6 weeks. Thereafter, the coordination of the muscular nervous system, aesthetics, temporomandibular joint were re-evaluated for 3 months by restoring the fixed provisional restoration. Through the above treatment process, the final restoration was completed with full mouth fixed prosthesis using monolithic zirconia, and functionally and aesthetically stable results were obtained.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.525-530
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• 2023

Although double-stage hanger is used in many homes for its space utilization and ease of installation, it is inconvenient for users to take off clothes hung on the upper bar due to its high height. Therefore, this paper proposes a new type of double-stage hanger that allows users to easily hang or take out clothes hung on the upper bar while maintaining the function of the existing double-stage hanger. 4-bar link mechanism is applied so that the upper bar can come down to a convenient height with one operation. In addition, an appropriate link shape, length, and joint type are selected so that the height is adjusted three-dimensionally to prevent overlapping of clothes hanging on upper/lower bars. FEA analysis is performed to ensure that the presented hanger shape can support the load of clothes during height adjustment and the feasibility of the three-dimensional height adjustment hanger is verified through fabrication.

• Journal of Veterinary Clinics
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• v.41 no.2
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• pp.79-87
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• 2024

The tarsus in dogs has a complex structure that makes its evaluation relatively challenging. Because an accurate diagnosis of the tarsus is difficult through basic examinations alone, imaging tests are essential. Previous studies have explored the anatomical and radiological features of the canine tarsus using several imaging modalities. However, the imaging utility of the tarsus across different modalities has not been thoroughly evaluated. This study aimed to visualize the tarsal structures using magnetic resonance imaging (MRI) and ultrasonography, compare their utility, and propose suitable imaging modalities and conditions for evaluating specific tarsal structures. Magnetic resonance imaging and ultrasound scans of the tarsus of four healthy dogs were performed, and two observers rated the utility of each image on a five-point scale. Although MRI is more beneficial for assessing the tarsal structures than ultrasound, ultrasound also appears clinically useful for evaluating the cranial tibialis muscle, deep digital flexor tendon, subcutaneous fat, joint space, and superficial digital flexor tendon. In addition, each structure of interest can be evaluated for optimal visibility using specific ultrasound sections, MRI sequences, and planes. In veterinary clinical practice, an initial assessment using ultrasound imaging with optimal visibility is required and if further evaluation is necessary, MRI examinations with optimal MRI sequences and planes can be performed.

• Journal of the Korean Society of Radiology
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• v.82 no.1
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• pp.82-98
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• 2021

Sesamoid bones and accessory ossicles are normal anatomic variants with varying morphological appearances and incidences. They are usually small osseous fragments with well-corticated margins located adjacent to the joint space and bone. Patients with sesamoid bones and accessory ossicles are usually asymptomatic and commonly encountered in clinical practice. These sesamoids and accessory bones are occasionally painful because of fractures, dislocations, degenerative changes, avascular necrosis, accessory bone infections, or abnormalities of the adjacent tissue, such as nerve entrapment, tenosynovitis, or soft tissue impingement. This article aimed to illustrate the imaging features of symptomatic sesamoids bones and accessory ossicles at various anatomic locations and describe their clinical features and radiological differential diagnosis.

• Clinics in Shoulder and Elbow
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• v.26 no.4
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• pp.390-396
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• 2023

Background: The subacromial (SA) space is a commonly used injection site for treatment of impingement syndrome. For shoulder stiffness, glenohumeral (GH) injections are commonly performed. However, in cases of impingement syndrome with mild shoulder stiffness, the optimal site of steroid injection has yet to be identified. Methods: This prospective, randomized study compared the short-term outcomes of ultrasound-guided GH and SA steroid injections in patients who were diagnosed with impingement syndrome and mild stiffness. Each group comprised 24 patients who received either a GH or SA injection of 40 mg of triamcinolone. Range of motion and clinical scores were assessed before and 3, 7, and 13 weeks after the injection. Results: GH and SA injections significantly improved the range of motion and clinical scores after 13 weeks of follow-up. Notably, targeting the GH joint resulted in an earlier gain of forward elevation, external rotation, and internal rotation in 3 weeks (P<0.001, P=0.012, and P=0.002, respectively) and of internal rotation and a Constant-Murley score in 7 weeks (P<0.001 and P=0.046). Subsequent measurements were similar between the groups and showed a steady improvement in all ranges of motion and clinical scores. Conclusions: GH injections may be more favorable than SA injections for treatment of impingement syndrome with mild stiffness, especially in improving the range of motion in the early period. However, the procedures showed similar outcomes after 3 months. Level of evidence: I.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.1
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• pp.149-156
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• 2006

Steel hollow section members have been widely used as a major material in the construction market due largely to their efficiency, their aesthetic appeal and to the technical development. But it is true that the commercial Program for dealing with a joint problem using hollow section members is not firmly established due to its uncertain and variable design parameters. The qualitative analysis program developed by using computer is introduced in this study. The results of that analysis are shown in the two-dimensional space in variable ranges and diagrams, so it would be useful to whom have not many experiences and knowledges. It is represented that the differences between Canadian code and the Korean standard for the connections of hollow section members. And It is verified that the software is applicable to the Preliminary design in steel tubular structures.

• Journal of Platform Technology
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• v.12 no.2
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• pp.23-33
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• 2024

The development of mixed reality (MR) technology has a great influence on the research and development of medical support equipment. In particular, it supports to respond effectively to emergencies occurring in the field. MR technology enables access to first aid and field support by combining virtual information with the real world so that users can see virtual objects in the real world. However, due to the nature of the equipment, there is a limitation in accurately matching virtual objects based on user vision. To improve these limitations, this paper proposes a 3D biometric object recognition and matching algorithm in the MR environment. As a result of the experiment, when a virtual object is rendered and visualized while equipped with an optical-based HMD from the user's side, it was possible to reduce the user's field of view error and eliminate the joint-loss phenomenon during skeleton recognition. The proposed method can reduce errors between the real user's field of view and the virtual image and provide a basis for reducing errors that occur in the process of virtual object recognition and matching. It is expected that this study will contribute to improving the accuracy of the telemedicine support system for first aid.

• Journal of Korea Society of Industrial Information Systems
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• v.29 no.4
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• pp.77-89
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• 2024

Knee osteoarthritis (OA) is a very common musculoskeletal disorder worldwide. The assessment of knee osteoarthritis, which requires a rapid and accurate initial diagnosis, is determined to be different depending on the currently dispersed classification system, and each classification system has different criteria. Also, because the medical staff directly sees and reads the X-ray pictures, it depends on the subjective opinion of the medical staff, and it takes time to establish an accurate diagnosis and a clear treatment plan. Therefore, in this study, we designed the stenosis length measurement algorithm and Osteophyte detection and length measurement algorithm, which are the criteria for determining the knee osteoarthritis grade, separately using CNN, which is a deep learning technique. In addition, we would like to create a grading system that integrates and complements the existing classification system and show results that match the judgments of actual medical staff. Based on publicly available OAI (Osteoarthritis Initiative) data, a total of 9,786 knee osteoarthritis data were used in this study, eventually achieving an Accuracy of 69.8% and an F1 score of 76.65%.

• Journal of the Korean Arthroscopy Society
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• v.16 no.2
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• pp.153-159
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• 2012

Purpose: This study aims at evaluating our results with a 5-year follow up of arthroscopic pull-out suture repair of posterior root tear of the medial meniscus. Materials and Methods: This study enrolled 30 cases who underwent a arthroscopic pull-out suture repair to treat the posterior root tear of the medial meniscus from January 2001 to May 2005 and followed up at least 5 years. The average follow-up period was 76 months (range, 60-90 months). Clinical results by use of the Lysholm knee score and radiographic grade by use of the Kellgren-Lawrence classification were evaluated and second-look arthroscopy was done in all cases. The clinical results were compared with trauma history, obesity, varus deformity and time to operation. Results: At the last follow up, the Lysholm knee score improved from 55 points to 86 points. For the radiological results, 23 cases displayed maintenance or improvement of the medial joint space on the follow up X-ray, but 7 cases displayed decrease of the medial joint space, and 1 case was lately performed total knee replacement due to progressive osteoarthritic change. Conclusion: Arthroscopic pull-out suture repair has a good result at 27 cases (90%) in minimum 5 years follow-up. The clinical improvement was significantly reduced in more severe varus angle.