• Journal of the Korean Society for Precision Engineering
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• v.10 no.4
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• pp.200-205
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• 1993

In many applications, the typical parallel-jaw end-effector of a robot arm has been remarkably satisfactory. But, it is not adequate for the applications such as complicated manipulation. In the study, a finger with 4 joints (so, having redundancy) was consturcted to investigate the characteristics of an articulated hand. Each joint was driven by one actuator, and the motor torque was transmited to each joint through a tendon-pulley system. In the context, major considerations for hardware design and the method to solve the inverse kinematics of a redundant manipulator were presented. Finally, the basic capabilities of an articulated hand were presented through experiments.

• The Journal of Korea Robotics Society
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• v.19 no.1
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• pp.1-7
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• 2024

This paper presents an under-actuated robotic hand inspired by the ligamentous structure of the human hand for a prosthetic application. The joint mechanisms are based on the concept of a tensegrity structure formed by elastic strings. These rigid bodies and elastic strings in the mechanism emulate the phalanx bones and primary ligaments found in human finger joints. As a result, the proposed hand inherently possesses compliant characteristics, ensuring robust adaptability during grasping and when interacting with physical environments. For the practical implementation of the tensegrity-based joint mechanism, we detail the installation of the strings and the routing of the driving tendon, which are related to extension and flexion, respectively. Additionally, we have designed the palm structure of the proposed hand to facilitate opposition and tripod grips between the fingers and thumb, taking into account the transverse arch of the human palm. In conclusion, we tested a prototype of the proposed hand to evaluate its motion and grasping capabilities.

• Journal of Biomedical Engineering Research
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• v.37 no.1
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• pp.15-20
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• 2016

Essential tremor is a neurological disorder with a tremor of the arms and hands. It is well known that essential tremor is characterized by the postural tremor and the action tremor. There has been no report on the quantitative difference in the characteristics of two tremor types. The purpose of this study was to investigate the possible difference in tremor characteristics of postural and action tremors. Seventeen patients with essential tremor ($68.9{\pm}7.9years$, 7 men, 10 women) participated in this study. Patients performed the tasks of postural maintenance (arms outstretched) and daily actions (spiral drawing). Three-axes (pitch, roll and yaw) gyro sensors were attached on index finger, back of hand and forearm, from which the segment and the joint angular velocities were calculated. Outcome measure was the tremor amplitude defined as the root-mean-square mean of the vector-sum angular velocity at segments and joints. Two-way ANOVA showed that task and joint had main factor on the tremor amplitude (p < 0.05). Post-hoc analysis revealed that tremor amplitude at the metacarpo-phalangeal joint was not affected by task (p > 0.05). However, tremor amplitude at the wrist joint differed among the tasks (p < 0.05), and it was greater in the action tasks than in postural task. Tremor was greater at finger segments than at hand and forearm and it increased in action tasks. The results of this study would be helpful for the understanding and task-specific treatments of the essential tremor.

• Korean Journal of Occupational Health Nursing
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• v.14 no.2
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• pp.164-170
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• 2005

Purpose: The present study attempted to find subjective musculoskeletal symptoms of operating room nurses (OR nurses) and then to use them as basic data for prevention and management of musculoskeletal symptoms of OR nurses. Method: This study was an exploratory research, and data were collected from OR nurses working in 8 polyclinics in Korea from July 26 to August 19, 2004, using a self-report questionnaire. The questionnaire contains items concerned with subjective musculoskeletal symptoms include ones with the presence of symptoms and with the degree of discomfort, in the joints such as neck, shoulder, arm/elbow, hand/wrist/finger and waist. For data collection, the aim of the study was explained to the operating room managers to obtain their help, and these questionnaires were sent to hospitals, and were retrieved by post. 271(90.3%) questionnaires were returned among those sent to 300 nurses. 249 questionnaires excluding 22 insufficient ones such as no response were used for data analysis. Data were analyzed using SPSS WIN 12.0. Subjective musculoskeletal symptoms were analyzed in the number and percentage. Result: 187(75.1%) nurses said they 'had' subjective musculoskeletal symptoms and 62 (24.9%) said they had 'nothing'. 130(52.2%), 125 (50.2%), 113 (45.4%), 86(34.5%), and 42 (16.9%) nurses had subjective musculoskeletal symptoms in waist, shoulder, hand/wrist/finger, neck, and arm/elbow, respectively. 51(27.3%) and 136 (72.7%) nurses complained of the pain in one site, and in two or more sites, respectively. In particular, 51% and 47.4% nurses said that they were 'discomforted' due to the pain in waist and in shoulder, respectively. Conclusion: Subjective musculoskeletal symptoms which OR nurses complained of were significant. This may cause difficulty in nursing tasks in the operating room. So various arrangements have to be made for OR nurse with subjective musculoskeletal symptoms at an early stage.

• Journal of Korean Association for Spatial Structures
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• v.20 no.2
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• pp.39-49
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• 2020

In this study, we will develop a hybrid cross-sectional shape of steel inserted type glued-laminated timber that can improve the strength of structural glued-laminated timber and maximize the ductility by using steel plate with excellent tensile and deformation ability. A total of three specimens were fabricated and the flexural performance test was carried out to evaluate the structural performance of the steel inserted type glued-laminated timber. In order to compare the effect of steel inserted glued-laminated timber, one structural glued-laminated timber test specimen composed of pure wood was manufactured. In addition, in order to evaluate the adhesion performance of the steel inserted, one each of a screw joint test specimen and a polyurethane joint test specimen was prepared. As a result, all the specimens showed the initial crack in the finger joint near the force point. This has been shown to be a cause of crack diffusion and strength degradation. The use of finger joints in the maximum moment section is considered to affect the strength and ductility of the glued-laminated timber beam. Polyurethane-adhesive steel inserted glued-laminated timber showed fully-composite behavior with little horizontal separation between the steel plate and glued-laminated timber until the maximum load was reached. This method has been shown to exhibit sufficient retention bending performance.

• Archives of Reconstructive Microsurgery
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• v.6 no.1
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• pp.87-95
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• 1997

Traumatic injury to the hand often leads to soft tissue defects with exposed tendons, bones, or joints. Though many new flap have been introduced, the choice of flap that would be best for the patient depends on such factors as the site, size, and degree of wounds. Additionally the selected surgical method should be yielded cosmetic and functional superiority by the one-staged reconstruction. In our experience, small to medium sized soft tissue defect with bone and tendon exposure of hand can be resurfaced with an arterialized venous free flap from the volar aspect of distal forearm. Wide and deep defects of the hand can be covered with a sensory cutaneous free flap such as the medial plantar free flap, dorsalis pedis free flap, and radial forearm free flap. Specialized flap such as wrap-around flap, toe-to-finger transfer, onychocutaneous free flap can be used for the recontruction of defect on the thumb and finger. Based on the above considerations and our clinical experience of 60 free flap cases of the hand, the various methods for the proper repair of soft tissue defects of the hand are described. And we obtained satisfactory functional and cosmetic results with 95% success rate of free flap.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.14 no.2
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• pp.156-162
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• 2014

A 25-month-old boy was referred to the hospital due to large head detected on routine physical examination. At visit, dysmorphic facial appearances, including broad nose, prominent forehead, and coarse face, were noted. Nasal obstruction with nasal voice, prominent adenoids, and bilateral middle ear effusions were detected. His abdomen was distended, and liver and spleen were palpated about 3 finger and 2 finger breadths, respectively. He was operated for bilateral inguinal hernias. The motion of both elbow joints was mildly limited on supination and pronation. Urinary level of glycosaminoglycan was elevated and the enzyme activity of iduronate sulfatase in leukocytes was decreased. The mutational analysis of the gene iduronate 2-sulfatase (IDS) revealed c.263G>A (p.Arg88His) mutation. His developmental scale showed delayed development and there was cardiac valvular involvement (tricuspid regurgitation and mitral valve prolapse). After the diagnosis of Hunter syndrome, enzyme replacement therapy started on a weekly basis without progression of any clinical features. Here we report a case of early diagnosed Hunter syndrome detected by large head on routine examination. Thus, it is important to associate Hunter syndrome in the patient with large head especially, if there is the history of bilateral inguinal hernia and prominent adenoids to increase the possibility of early diagnosis and treatment.

• Journal of the Korea Computer Graphics Society
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• v.21 no.5
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• pp.29-36
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• 2015

Human fingers are essential parts of the body that perform complex and detailed motion. Expression of natural finger motion is one of the most important issues in character animation research. Especially, keyboard typing animation is hard to create through the existing animation pipeline because the keyboard typing typically requires a high level of dexterous motion that involves the movement of various joints in a natural way. In this paper, we suggest a method for the generation of realistic keyboard typing motion based on physics simulation. To generate typing motion properly using physics-based simulation, the hand and the keyboard models should be positioned in an allowed range of simulation space, and the typing has to occur at a precise key location according to the input signal. Based on the observation, we incorporate natural tendency that accompanies actual keyboard typing. For example, we found out that the positions of the hands and fingers always assume the default pose, and the idle fingers tend to minimize their motion. We handle these various constraints in one solver to achieve the results of real-time natural keyboard typing simulation. These results can be employed in various animation and virtual reality applications.

• Archives of Plastic Surgery
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• v.33 no.4
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• pp.485-490
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• 2006

Purpose: As the traditional treatment of the Wassel's type I or II of bifid thumb, Bilhaut-Cloquet, has always been the standard method despite several disadvantages such as tearing of the finger nail, injuries of the growth plate, joint instability, and long visible scarring. To overcome these drawbacks, we applied a modified Bilhaut-Cloquet Method. Methods: The subjects used for the this study were 10 of 20 patients evaluated. The patients underwent modified methods under every type of Wassel's classification. We designed a central wedge Zig-Zag incision and removed the nail and bony tissues in the remaining digit, but not soft tissue if possible, and transferred the ligaments, tendons, and soft tissue to the remaining thumb from the extra digit. We evaluated the patients' lack of extension, the total ROM of the MP and IP joints, the ROM of IP joints, and the lateral deviations of the reconstructed thumb. Results: The results were encouraging, with all patients showing a good functional and aesthetic outcome. Conclusion: The modified method proved a very effective procedure in the treatment of bifid thumb in all types, especially types I or II.

• Journal of muscle and joint health
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• v.9 no.2
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• pp.144-153
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• 2002

This study was designed to explore use of unconventional treatments and identify related variables of patients with rheumatic disease. One hundred fifty rheumatic patients were recruited from two university based rheumatic centers according to selection criteria. Collected data were analyzed using SAS program through with a structured questionnaire. T-test, ANOVA, and Scheffe's test were adopted. The results were as follows: 1. 77.7% of the subjects were over forties and mean age was 48.5 years. 74.0% were women and 73.2% were living with their spouse. 82.0% of them was good or moderate or good economic status, 38.3% was university graduates. 2. 58.0% of the subjects had rheumatoid arthritis, and mean duration of suffering rheumatic disease was 6.5 years. 89.3% of them had joint pain and their mean pain score was 4.07. Most painful joints were hip(58.0%), finger(42.0%), wrist(42.0%), and the number of painful joint was 5.4. 70% of the subjects using unconventional treatments, the most common treatments using them was herb medicine(42.7%) and acupuncture(36.7%). 3. Level of pain was different according to subject's age, educational background, diagnosis, number of painful joints, and using unconventional treatments or not. It is recommended that use of a larger sample to understand more about unconventional treatments and pain of patients with rheumatic disease. More research is needed to consider developing individual nursing interventions for their well-being and quality of life.