• Journal of the Semiconductor & Display Technology
• /
• v.23 no.2
• /
• pp.107-113
• /
• 2024

Scheduling of semiconductor test facilities has been crucial since effective scheduling contributes to the profits of semiconductor enterprises and enhances the quality of semiconductor products. This study aims to solve the scheduling problems for the wafer burn-in test facilities of the semiconductor back-end process by utilizing simulation and deep reinforcement learning-based methods. To solve the scheduling problem considered in this study. we propose novel state, action, and reward designs based on the Markov decision process. Furthermore, a neural network is trained by employing the recent RL-based method, named proximal policy optimization. Experimental results showed that the proposed method outperformed traditional heuristic-based scheduling techniques, achieving a higher due date compliance rate of jobs in terms of total job completion time.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.33 no.4
• /
• pp.307-311
• /
• 2007

Purpose: The aim of this study was simply assessing linear measurements in the lateral and medial approach, respectively, for bone harvesting using anatomic and three-dimensional(3D) computed tomographic(CT) analyses on a dried cadaveric proximal tibia. In addition, the availability of the three-dimensional computed tomographic(3D-CT) analysis was also estimated. Materials and methods: Ten dried proximal tibia were obtained from five Korean cadavers. Four the reference points, the SM(superior-medial), IM(inferior-medial), SL(superior-lateral), and IL(inferior-lateral) were marked around the tibial tuberosity. The PM(posterior-medial) and PL(posterior-lateral) points were randomly marked at points farthest from the lateral and medial reference points, respectively, in the posterior border of the superior articular surface of both condyles. All measurements were obtained on the dried proximal tibia. After computed tomography had been performed, the three dimensional images were reconstructed using V works $4.0^{TM}$(Cybermed Inc., Seoul, Korea), and the length between the reference points were measured three dimensionally using the method described above. The error between the mean actual and mean 3D-CT measurements was calculated in order to determine the availability of the three dimensional computed tomographic analysis. Results: The length between the reference points was greatest at the IL-PM, which averaged $65.39mm{\pm}10.35$. This was followed by the SL-PM with $63.24mm{\pm}8.10$, the IM-PL with $58.09mm{\pm}10.02$, and the SM-PL with $51.99mm{\pm}9.06$. The differences between the IL-PM and SM-PL were 13.4 mm. The mean values were 55.04 mm in the medial approach and 64.32 mm in the lateral approach, and the differences between medial and lateral were 9.28 mm. The error between the mean actual and mean 3D-CT measurements was 0.31% and the standard deviation was 0.28%. Conclusion: The anatomical and three dimensional computed tomographic analysis indicates that there was only a 9.28 mm linear difference between the lateral and medial approach. This is consistent with previous studies, which showed that there was little difference between the two approaches in terms of the bone volume. In addition, the error(0.31%) and the standard deviation(0.28%) were considered low, demonstrating high accuracy of 3D-CT. Therefore it can be used in preoperative treatment planning.

• Journal of Korean Foot and Ankle Society
• /
• v.15 no.2
• /
• pp.62-67
• /
• 2011

Purpose: The authors evaluated the differences between K-wires and Cannulated screw, plate for fixing the proximal metatarsal chevron osteotomy of moderate and severe hallux valgus. Materials and Methods: There were 62 patients (79 feetz) who were moderate and severe degree hallux valgus according to the classification of Mann. They all got the proximal chevron osteotomy when correcting the deformity. We divided the patients into 4 groups, Two K-wire fixed group as A, one cannulated screw fixed group as B. Two cannulated screw fixed group as C, Plate fixed group as D, Group A were patients (26 feet) and Group B were patients z(9 feet), Group C were patients (31 feet) and Group D were patients (13 feet). Preoperative, postoperative and follow-up hallux valgus angle (HVA) and intermetatarsal angle (IMA) were measured for each patient. ANOVA test and Student t-test were done for statistical analysis. Results: Mean follow up period was 43.8 months (range: 12~82 months). Preoperative mean IMA was $16.4{\pm}3.5$, $17.7{\pm}11.3$, $17.3{\pm}5.9$ and $16.6{\pm}2.3$ degrees in respectively group A, B, C, D. Immediate postoperative mean IMA was $5.6{\pm}3.4$, $7.3{\pm}4.4$, $7.6{\pm}4.4$ and $6.7{\pm}2.8$ degrees in respectively group A, B, C, D. The final mean IMA was $8.9{\pm}4.5$, $15.2{\pm}7.5$, $10.3{\pm}4.4$ and D $7.7{\pm}3.5$ degrees in respectively group A, B, C, D. There were significant statistical increase in final mean IMA of group B and C (p<0.05). Conclusion: The IMA was significantly increased in the group which used one or two cannulated screw for fixation on follow up, therefore more caution should be needed when using one or two cannulated screw fixation technique after proximal chevron osteotomy.

• Clinics in Shoulder and Elbow
• /
• v.2 no.2
• /
• pp.187-198
• /
• 1999

Purpose: The authors compared the results of Ender nailing for the proximal humerus fractures with those of the conservative methods radiographically. Materials and Method: Nine patients(mean age: 69 years.) received Ender nailing, and the other nine patients, conservative treatments(mean age: 73 years). All fractures were 2 part fractures. The Ender nails were inserted either through posterior elbow approach or transepicondylar approach. A simple Velpeau bandage was applied to the conservative treatment group. The average follow-up was 15 months. Results: The initial status of the anatomical reduction, i.e., the values of the medial shift, overlapping and the varus agulation, were little changed at follow-up radiographs in both the Ender nailing group and the conservative treatment group. There was no significant difference for the status of anatomical reduction between the Ender nailing group and the conservative treatment group. The stability of fixation by Ender nails, i.e., the degree of fanning out of the nails was poor in most cases. Not a few problems/complications happened in cases of Ender nailing group; back­ing out of the nail in three cases, penetration of the nails into the humeral heads in 3, fractures or cracking of the humerus around the nail insertion area in 4 and reduction loss in one. Conclusion: We could not get better results with the use of Ender nail. We use no longer Ender nails for the proximal humerus fractures. Further studies are needed for the better option for the proximal humerus fractures.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.29 no.1
• /
• pp.26-34
• /
• 2003

Intraoral Vertical Ramus Osteotomy,along with Sagittal Split Ramus Osteotomy,is an popular surgical technique performed on mandibular prognathism. However Intraoral Vertical Ramus Osteotomy has been suspected for an initial mobilization at the healing phase of segment because it does not employ the rigid fixation between segments. To execute a study on the healing phase of segment after Intraoral Vertical Ramus Osteotomy on the horizontal plane, 102 patients (204 parts) who were diagnosed mandibular prognathism and took Intraoral Vertical Ramus Osteotomy at the Yonsei University dental hospital were observed during the period of before operation, immediately postoperation, 1 month, 3 months, 6 months, and 12 months. The change in the width of segment and horizontal angle of proximal segment and condylar head on the Submentovertex Cephalogram taken from those patients represented following results. 1. The width of proximal and distal segment decreased with the lapse of time. It decreased into 84.5% between immediate postoperative and 6M and even continued to decrease till 12M. 2. The horizontal angle of the proximal segment did medial rotation according as the lapse of time and rigorously continued till 3M. The rotation angle of condylar head indicated its tendency of recurrence to the original position but the entire recurrence was not allowed. The bigger an initial angle was, the higher was the tendency of recurrence after the operation while the rotation angle remained still bigger. 3. After grouping into group 1, group 2,and group 3 based on the extent of the variation of rotation angle of condylar head at immediate postoperative, the variation of rotation angle was measures in each group. The result presented that the initial rotation angle of condylar head had correlation with that of proximal segment but had no relation with the extent of setback of the mandible. However a quantitative analysis alone is not a sufficient method for analyzing the healing phase of segment on the horizontal plane.Therefore a multilateral analysis using 3 dimensional data such as CT is recommendable for the future study.

• Journal of Oriental Medical Thermology
• /
• v.5 no.1
• /
• pp.69-77
• /
• 2006

Purpose : There are many patients with cold hypersensitivity who want oriental medicine treatment. But there has been no study of acupucture treatment effect on patients. So we examined effects of acupuncture treatment at different acupuncture points and compared results of 1st cold stress test and 2nd cold stress test. Method : 8 patients with hand cold hypersensitivity applied for this study. To rule out an bias, we excluded the patients with skin diseases, spinal nerve disease of cervial spine, external wounds. We measured body temperature with D.I.T.I. We performed cold stress test(CST) by 6 thermographic observation using D.I.T.I ; the 1st was taken after 15 minutes-resting, the 2nd was immediately taken after 1 minute soak in $20^{\circ}C$ water, the 3rd was taken at 10 minutes after the soak, and after a week, the 4th was taken after 15 minutes resting, the 5th was immediately taken after 1 minute soak in $20^{\circ}C$ water, the 6th was taken after 10 minutes with acupunture treatment. There were two groups of patients. First group was acupuncture that performed acupuncture therapy on distal points. Second group was acupuncture that performed acupuncture therapy on proximal points. We compared first CST and second CST recovery rate result. Results : The recovery rate at distal points acupuncture therapy was higher than before of that. but not significantly different. The recovery rate at proximal points acupuncture therapy was significantly higher than before of that. The recovery rate of both the back, the palms, all fingers of after proximal acupuncture therapy was significantly higher than before of that. Conclusions : Acupuncture could be effective therapy method on cold hypersensitivity, especially using proximal acupuncture points could be good at cold hypersensitivity patients. This was pilot study of very small samples, results had limitations. For further results more examine would be needed.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.33 no.4
• /
• pp.430-439
• /
• 2009

Posterior Cruciate Ligament (PCL) plays an important role in knee extension. Rotational instability due to injured PCL can be restored by various PCL reconstruction methods. In this study, the initial lengthening affected by fixation device and location was demonstrated, and furthermore, the slippage and the relationship between lengthening ratio and slippage ratio in the calcaneus and soft tissue fixation methods was newly suggested. Eight specimens of proximal tibia and Achilles tendon grafts were harvested from four cadavers and divided into four groups in regard to the four different types of transtibial fixation techniques. The cyclic load ranged from 50 N to 250 N applied to each graft fixed to proximal tibia in 55 degrees. The initial lengthening ratio to the total elongation has been approximately constant regardless of the fixation methods. The soft tissue fixation method with an interference screw showed about 56.4% slippage ratio to the total elongation and the same method with a double cross-pin presented about 45.4% slippage ratio. The soft tissue fixation method with an interference screw demonstrated approximately 2 mm less total elongation and about 13% more slippage than lengthening because of poor fixation compared to the same method with a double cross-pin.

• Journal of Korean Foot and Ankle Society
• /
• v.16 no.2
• /
• pp.87-93
• /
• 2012

Fractures located at the metaphyseal/diaphyseal junction at the base of the fifth metatarsal were first described by Sir Robert Jones in 1902. However, ever since, there has been disagreement and debate regarding the diagnosis, classification, pathomechanics, the incidences, and potential causes of delayed unions and nonunions, and the optimal method of treatment. It appears to be widely agreed that proximal fractures of the metaphyseal/diaphyseal region of the fifth metatarsal are prone to delayed union or even nonunion. Several classifications of proximal fifth metatarsal stress fractures have been devised. Torg et al. classified fractures involving the proximal part of the diaphysis of the fifth metatarsal into three types. The Torg classification is a good grading system that can be used to determine the type of surgery needed as well as for the prediction of prognosis. The ''plantar gap'' might add to the decision-making process for surgery and improve the prediction of patient prognosis. In addition, the new classification using 'plantar gap' might be used for classification of fifth metatarsal stress fracture. Fifth metatarsal stress fractures can be treated conservatively or surgically, and excellent results have been reported for surgery with rapid recovery in athletes. Intramedullary screw fixation has become a popular form of fixation for fifth metatarsal stress fractures. Bone grafting presents the problems of a longer recovery time and additional skin incision for harvesting. The modified tension band wiring is an useful and simple option for surgical treatment of challenging fifth metatarsal stress fractures.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.23 no.2
• /
• pp.137-145
• /
• 2020

Purpose: The Oral-anal Transit Test (OTT) is a simple method of obtaining information about colonic transit. We aim to assess the correlation of OTT with the neuromuscular integrity of the colon determined by colonic manometry (CM). Methods: All patients who had OTT followed by CM were evaluated. Less than 6 of 24 markers remaining on OTT was considered normal. CM was performed per previously published guidelines. A normal CM was defined as at least one High Amplitude Propagating Contraction progressing from the most proximal sensor through the sigmoid colon. Results: A total of 34 patients underwent both OTT and CM (44% male, age 4-18 years, mean 11.5 years, 97% functional constipation +/- soiling, Hirschsprung's Disease). Of normal and abnormal OTT patients, 85.7% (6/7) and 18.5% (5/27) respectively had normal CM. When all markers progressed to at least the sigmoid colon, this was 100% predictive against colonic inertia. Greater than 50% of patients with manometric isolated sigmoid dysfunction had markers proximal to the recto-sigmoid. Conclusion: OTT and CM are both valuable studies that assess different aspects of colonic function. OTT can be used as a screening test to rule out colonic inertia. However, the most proximal extent of remaining markers does not predict the anatomical extent of the manometric abnormality, particularly in isolated sigmoid dysfunction.

• Journal of Korean Physical Therapy Science
• /
• v.2 no.3
• /
• pp.599-608
• /
• 1995

If a controlled sensory stimulation is given to the specific receptors, a reflex movement and motor engrams is achieved by the principle of neurophysiology. Based on this theoretical background, we choose 80 healthy person(male 40,female 40) and compare chronaxie of before stimulation with after stimulation. Also we measured chronaxie with same method. Stimulation was applied to the muscle belly by tapping. The results are summarized as follows; 1. The mean value of rheobase measured from the proximal part of upper extremity is 3. 56mA for male, 4.04mA for female. 2. The mean value of rheobase measured from the lower extremity is 4.19mA for male, 4. 37mA for female, which is higher than that of upper extremity for both male and female. 3. The mean value of chronaxie from the proximal part of upper extremity is 0.91msec for male, 0.87 msec for female, which means male is higher than female, and the average is 0.82msec. 4. The mean value of chronaxie from the proximal part of lower extremity is 1.04msec for male, 1.14msec for female, which means female is higher than male. 5. The decrease of rheobase after stimulation is prominent at the triceps brachii for male, biceps brachii for female. 6. The decrease of rheobase after stimulation is prominent at the tibialis anterior for both male and female. 7. The decrease of chronaxie after stimulation is prominent for both male and female at the triceps brachii from upper extremity and at the tibialis anterior from lower extremity for both male and female.