International Journal of Precision Engineering and Manufacturing
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v.2
no.3
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pp.69-78
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2001
This paper presents a process and operation planning system and an NC code post-processor for effective machining of press dies for production of cars. Based on the machining feature, major parts of press dies are categorized into 15 groups and a standard process plan is defined for each group. The standard process plan consists of a series of processes where a process is defined as a group of operations that can be done with one setup. Details such as cutting tools, cutting conditions, and tool paths are decided at the operation planning stage. At the final stage of process and operation planning, the NC code post-processor adjusts feedrates along the tool path to reduce machining time while maintaining the quality. The adjustment rule is selected based on the machining load estimated by virtual machining.
Objective: This study was performed to evaluate the usefulness of early operation in children with traumatic subdural hygroma. Methods: The subjects were nine patients (Glasgow coma scale (GCS) score was below 10 and age was below 10 years old) who developed subdural hygroma after trauma between January 2000 to December 2002. Subduroperitoneal shunt was performed in one group and not performed in the other group. We analyzed the GCS score on admission and at 1 year after operation. Overall clinical results were evaluated retrospectively. Results: Patients who underwent operation exhibited higher GCS scores at 1 year after trauma compared to those in the patients who were treated by conservative therapy(p<0.05). Conclusion: The early operation could be an effective treatment to children with subdural hygroma who showed delayed improvement of consciousness and to patients with hygroma that didn't decrease or was above moderate amount.
This study attempted to contribute to the clinical application of implant operation by making a quantitative nerve examination using a neurometer for the evaluation of sensory disturbances that could be incurred after the implantation in the dental clinics, and it intended to establish an objective guideline in the evaluation of sensory nerve after the operation of implant. An inspection was performed with the frequencies of 2000Hz, 250 Hz and 5 Hz before and after the operations of tooth implant using $Neurometer^{(R)}$ CPT/C (Neurotron, Inc. Baltimore, Maryland, USA) for 44 patients who had performed an implant operation among the patients coming to Daejeon Sun Dental Hospital in 2006 and 30 people for control group. The measuring sites were maxillary nerve ending and mandibular nerve ending of trigeminal nerve according to the implant operating regions. The current perception threshold (CPT) by each nerve fiber was specifically responded under the electric stimulation of 2000 Hz in case of $A{\beta}$ fiber and of 250 Hz in case of $A{\delta}$ fiber and of 5Hz in case of C fiber. The CPT test could be performed to assess the damages of peripheral nerve in the trigeminal nerve area and it stimulated selective nerve fibers by generating the electricity of specific frequency in the peripheral nerve area. The nerve fibers with varied thickness were responsive selectively to the electric stimulation with different frequencies; accordingly, they applied the electric stimulation with different frequencies and the reaction threshold of $A{\beta},\;A{\delta}$ and C fibers selectively responsive to each electric current could be individually evaluated. In the assessment through the CPT, the increase and decrease of the CPT could be measured so that sensory disturbances such as hyperaesthesia or hypoaesthesia could be diagnosed. This study could obtain the following results after the assessment of the CPT before and after the implant operation. 1. In the assessment before and after the implant operation, the CPT in the frequencies of 2000 Hz, 250 Hz, 5 Hz for maxillary branch increased on the whole after the operation and the CPT for mandibular branch in the $A{\beta}$-fiber(2000 Hz) and C-fiber(5 Hz )after the operation increased statistically significantly. 2. For the groups of patients with medically compromised or its subsequent medicinal prescription, there were no significant differences before and after the implant operation and for the control groups, significantly high CPT was shown after the implant operation in the left $A{\beta}$-fiber(2000 Hz) and C-fiber(5 Hz). 3. In the comparison of the measured value of the CPT before the operation between the control group and the implant operation group, the latter group had a significantly high measured value of the CPT in the right $A{\beta}$-fiber(2000 Hz) and C-fiber(5 Hz) and there were significant differences in $A{\beta}$-fiber(2000 Hz) in the CPT assessment after the implant operation for the control group. 4. Male participants had higher CPT than female counterparts; however, there were no statistic significances. In the CPT evaluation before and after implant operation, there were no statistical differences in the male group while the right C-fiber(5 Hz) and left $A{\beta}$-fiber(2000Hz) were significantly high in the female group. 5. In the comparison between the group who complain sensory disturbance and the other group, the CPT increased on the whole in the former group, but there were no statistical significances. In the groups, whom there was an increase in VAS, the CPT after the implant operation in the right C-fiber(5 Hz) increased significantly; meanwhile, in case that the VAS mark was '0' before and after the operation, the CPT after the operation in the left $A{\beta}$-fiber(2000 Hz) increased significantly. This study suggested that the CPT measurements using $Neurometer^{(R)}$ CPT/C, provide useful information of objective and quantitative sensory disturbances for tooth implantation.
Park, Tae Seo;Nam, Su Bong;Choi, Jae Yeon;Bae, Sung Hwan;Lee, Jae Woo;Kim, Hyun Yul
Archives of Plastic Surgery
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v.45
no.4
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pp.340-344
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2018
Background In performing extended latissimus dorsi (ELD) flap procedures, a skin paddle design on the bra line helps reduce visible scarring. This improves the patient's satisfaction with the outcome. However, such a design leads to a longer operation time and increased fatigue of the surgeon due to the narrow operative field. In this study, the authors propose a method that elongates the axillary incision line posteriorly by 1.5 cm from the lateral border of the latissimus dorsi muscle. We examined whether this method could shorten the operation time and compared the incidence of complications between patients who underwent this novel procedure and patients who underwent the traditional procedure. Methods In this study of patients who underwent ELD flap procedures for immediate breast reconstruction, 89 underwent surgery with the elongated axillary incision and 45 underwent surgery without the elongated incision. The total operation time and complications were retrospectively examined based on the patients' medical records, and we examined whether there was any statistically significant difference in the total operation time. Results In the experimental group with the elongated axillary incision, the operation time ranged from 125 to 255 minutes (median, 175 minutes). In contrast, in the control group without the elongated axillary incision, the operation time ranged from 142 and 340 minutes (median, 205 minutes). The operation time was statistically significantly different between the two groups, and no significant complications were observed in the experimental group. Conclusions Elongation of the axillary incision alone may shorten the operation time of the ELD flap procedure without causing additional complications.
Backgroud. To determine the influence of age at operation upon surgical outcome in patients with isolated secundum atrial septal defect, retrospective clinical analysis was done. Material and method. From June, 1976 to December, 1991, 146 patients, 63 male and 83 female patients ranging in age from 13 months to 56 years, were operated on for isolated secundum atrial septal defect. The patients were divided into 3 groups according to their age at operation: Group I [<20 years old], 91 patients[62.3%]; Group II [21 to 40 years old], 44 patients[30.1%]; GroupIII[>41 years old], 11 patients[7.6%]. Significant differences in clinical features, hemodynamic function, early and late results between age groups were speculated. Results. One hundred thirty-one patients[89.6%] were symptomatic at the time of operation, the most common symptoms being dyspnea on exertion, recurrent respiratory infection, palpitation and chest pain. Patients in NYHA class III or IV were 3.3% in group I, 25% in groupIII, and 54.5% in group Ill. Hemodynamic data was available for 138 patients [94.5%]. Significant pulmonary hypertension [MPA systolic pressure $^3$ 40mmHg] was noted in 22 patients [15.9%]. Patients with pulmonary vascular disease [Rp/Rs>1.25] were 2% in group I, 7.3% in group Il, and 9.1% in groupIII. But there were no significant differences between the age groups in the size of the shunt or the ratio of pulmonary to systemic flow. Atrial septal defects were closed with direct suture in 144 patients and patch repair was performed in 2 patients with high defect. Atrial arrhythmia [8.2%] was the most common postoperative complication. The mean [LSD] duration of follow-up in all patients was 16$\pm$22 months [range, 1~96 months]. Functional result was excellent regardless of the age groups. During follow-up period, late cardiovascular events were arrhythmia [7 cases], reoperation for recurrent ASD [2 cases], and premature late death due to bacterial endocarditis [1 case]. Incidence of preoperative and late atrial fibrillation was significantly higher in older age group. Conclusion. Age at operation is one of the most important predictor of early and late surgical outcome with its impact on the following factors : 1] hemodynamic alterations and ventricular dysfunction due to longstanding volume and pressure overload, 2] pulmonary vascular disease, and 3] atrial arrhythmia including atrial fibrillation as a result of atrial dilatation. Therefore, among patients with surgically repaired atrial septal defects, those operated on over the age of 20 require careful supervision on the long-term basis.
The purpose of this study was to determine the effects of music therapy on changes in the vital signs of patients about to undergo an operation. The patients listened to the music at a time when they were feeling preoperative anxiety up until the preanesthesia was given in the operating room. The subjects for this study were selected from sixty patients to undergo operations, who were hospitalized at Dong Eui hospital in Pusan city. They were assigned to two groups, thirty to the experimental group and thirty to the control group. The subjects were from 20 years old to 69 years old, and had no other problem except the one requiring the operation, and no premedication. The data were collected during the period from July 1 to September 30, 1993. The method used in this study was to measure state-anxiety on the ward in the morning of the operation, and vital signs immediately before leaving for the operating room. Vital signs were measured immediately before the anesthesia was given and after the experimental group had listened to the music during the ten minutes needed to prepare the operation setting. The control group just waited during ten mimutes. Vital signs were check again before the anesthesia was given. The data were analyzed by descriptive statistics, mean±SD, p-value, and t-test using the SPSS progrom. The results of this study are : 1. Systolic blood pressure taken in the operating room was elevated, over the level measured on the ward, by 5.00 ± 15.26㎜Hg in experimental group and 18.67±14.56㎜Hg in control group. (t=-3.5496, p=.0008) 2. Diastolic blood pressure was elevated by 6.67±12.95㎜Hg in experimental group and 18.67±12. 79㎜Hg in control group. (t=-3.6100, p=.0006) 3. Pulse was elevated by 2.931±9.44 / min in experimental group and 8.03±8.37 /min in control group. (t=-2.2144, p=.0307) 4. Respiration was elevated by 0.60±1.35 /min in experimental group and 1.57±1.48 /min in control group. (t=-2.6409, p=.0106) 5. Body temperature was down by 0.13±1.91'c in experimental group and elevated by 1.13±1.11'c in control group. (t=-3.1471, p=.0026) Thus, in this study there was a statistically significant difference in the change in the vital signs between the experimental group treated with music therapy and the control group which received no treatment. Because music therapy is valuable to decrease the anxiety of patients facing operations, the result of this study support its effect in relieving anxiety as a valuable nursing intervention. From this study, the following recommendations can be made : First, it is necessary to further study music therapy to develope a better system and determine optimal time. Second, it is necessary that more detailed re-search on measurement of changes in vital signs be done to determine changes over time intervals.
Purpose: The objective of the present study was to determine the capability of electrospun silk fibroin as a biomaterial template for bone formation when mixed with nano-hydoxyapatite in vivo. Materials and Methods: Ten New Zealand white rabbits were used for this study and bilateral round shaped defects were formed in the parietal bone (diameter: 8.0 mm). The electrospun silk fibroin was coated by nano-hydroxyapatite and grafted into the right parietal bone (experimental group). The left side (control group) did not receive a graft. The animals were sacrificed at 6 weeks and 12 weeks, humanly. The microcomputerized tomogram (${\mu}CT$) was taken for each specimen. Subsequently, they were undergone decalcification and stained for the histological analysis. Results: The average value of all measured variables was higher in the experimental group than in the control at 6 weeks after the operation. BMC in the experimental group at 6 weeks after operation was $48.94{\pm}19.25$ and that in the control was $26.17{\pm}16.40$ (P = 0.027). BMD in the experimental group at 6 weeks after operation was $324.59{\pm}165.24$ and that in the control was $173.03{\pm}120.30$ (P = 0.044). TMC in the experimental group at 6 weeks after operation was $19.50{\pm}6.00$ and that in the control was $10.52{\pm}6.20$ (P = 0.011). TMD in the experimental group at 6 weeks after operation was $508.88{\pm}297.57$ and that in the control was $273.54{\pm}175.91$ (P = 0.06). Gross image of both groups showed higher calcification area at 12 weeks than them in 6 weeks. The average value of ${\mu}CT$ analysis was higher at 12 weeks than that in 6 weeks in both groups. BMC in the experimental group at 12 weeks after operation was $51.21{\pm}8.81$ and that in the control was $33.47{\pm}11.13$ (P = 0.010). BMD in the experimental group at 12 weeks after operation was $323.39{\pm}21.54$ and that in the control was $197.75{\pm}76.23$ (P = 0.012). TMC in the experimental group at 12 weeks after operation was $21.44{\pm}5.30$ and that in the control was $13.31{\pm}4.17$ (P = 0.008). TMD in the experimental group at 12 weeks after operation was $524.47{\pm}19.37$ and that in the control was $299.60{\pm}136.20$ (P = 0.016). Conclusion: The rabbit calvarial defect could be successfully repaired by electrospun silk nano-fiber combined with nano-hydroxyapatite.
Purpose: The purpose of this study is to compare the radiological results of fixation using the femoral neck system (FNS) and cannulated screw (CS) for treatment of femoral neck fractures. Materials and Methods: A retrospective study of patients with femoral neck fractures who underwent internal fixation and had follow-up of more than six months from 2010 to 2020 was conducted. A total of 87 patients were enrolled in the study. The FNS group included 20 patients and the CS group included 67 patients. Classification of fractures was performed according to Garden and Pauwels classification. Operation time, intraoperative blood loss, sliding distance of the implant, lateral soft tissue irritation caused by implants, and complications were evaluated. Results: The mean operation time was 40.30 minutes in the FNS group and 46.84 minutes in the CS group. The mean intraoperative bleeding volume was 51.25 mL in the FNS group and 72.16 mL in the CS group. Bone union was achieved in 18 patients in the FNS group (90.0%) and in 61 patients in the CS group (91.0%). The mean sliding distance of the implant was 4.06 mm in the FNS group and 3.92 mm in the CS group. No patients in the FNS group and 12 patients in the CS group complained of soft tissue irritation. Conclusion: A shorter operative time, less intraoperative bleeding, and less irritation of soft tissue were observed in the FNS group. FNS could be an alternative to CS for fixation of femoral neck fractures.
Zhang, Kun;Wang, Hui;Wang, Kaiqiang;Cui, Jian;Chen, Bo;Li, Di
International Journal of High-Rise Buildings
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v.7
no.3
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pp.243-253
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2018
The construction of rapid developing super high-rise buildings constantly faces great challenges and the innovation of construction equipment is a focus of these challenges. In this paper, three new inventions including the operation platform, tower crane and hoist are put forward around two of the most important issues of super high-rise building construction: vertical transportation and operation environment. Study background, composition of the equipment, working principles and key technologies are introduced in sequence. In the end, the paper summarizes the main problems in the further development of construction equipment.
I clinically analysed 13 cases of broncholithiasis which treated surgically and found only four cases of broncholithiasis caused by the erosion of the peribronchial lymph node named by extrinsic formation[Group II], and nine cases of broncholithiasis caused by intrinsic formation[group I] which indicates that no evidence of the erosion of the calcified per-ibronchial lymph node into the bronchial tree was found. This study is performed to see any differences between two groups regarding presenting symptoms, locations of broncholith, preoperative diagnosis, a history of pulmonary tuberculosis, a procedure of operation, and chemical compositions of broncholiths from both groups. There was no difference between two groups in the presenting symptoms, the procedure of operation, and chemical compositions of broncholiths. The broncholits from group two is located in the right middle lobe bronchus, and the broncholiths of group one were distributed at various bronchi, In group one, only five cases out of nine had preoperative diagnosis[55.5%], but in group two, all four had preoperative diagnosis. All cases had good postoperative courses without any complication and recurrences.
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