• Korean Journal of Computational Design and Engineering
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• v.13 no.1
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• pp.58-66
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• 2008

The artificial discs have recently used to preserve the motion of the treated segment in lumbar spine surgery. However, there have been lack of biomechanical information of the artificial discs to explain current clinical controversies such as long-term results of implant wear and excessive facet contact forces. In this study, we investigated the biomechanical effects of three artificial implants on the lumbar spinal segments by finite element analysis. The finite element model of intact lumbar spine(L1-S) was developed and the three implants were inserted in L4-L5 segment of the spine model. 5 Nm of flexion and extension moments were applied on the superior plate of L1 with 400 N of compressive load. Excessive motions and high facet contact forces at the surgical level were generated in the all three implanted models. In the flexion, the peak von-Mises stresses in the semi-constrained type implant was higher than those in the un-constrained type implant which would cause wear on the polyethylene core. The results of the study would provide a biomechanical guideline for selecting optimal surgical approach or evaluating the current design of the implants, or developing a new implant.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.3 s.43
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• pp.257-269
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• 1992

In the area of fashion business, market segmentation strategy has been paid attention for the purpose of assigning proficiently marketing resources. The use of fashion information in purchase decision process can serve as a base for market segmentation strategies. The purpose of this study was to identify four segmented profiles which are labelled as Print-oriented, Audio-visual oriented, Store intensive, and Pal advice group. Objectives were to determine fashion interest, fashion attitude and apparel selection criteria from each segment. For this study, the questionnaire was adminisered to 261 teachers and data were analyzed by using ANOVA, Regression and Pearson's Correlations. The results were as follows. 1. Print-oriented group had a positive attitude about fashion and they tended to place value on aesthetic and other-oriented criteria in selecting apparel. 2. Audio-visual oriented group had a strongly positive attitude about fashion but they tended to be less active toward buying fashion products and place much more value on other-oriented criteria in selecting apparel. 3. Store intensive group tended to be active toward buying fashion products. They had a positive attitude about fashion and placed value on aesthetic criteria in selecting apparel. 4. Pal advice group had a less positive attitude about fashion and tended to place value on economical and practical criteria in selecting apparel. Based on the profile of the each segment, it was suggested to express lingual or non-lingual symbols and to create concepts for meeting the needs of the segment

• Journal of Korean Foot and Ankle Society
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• v.18 no.4
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• pp.178-182
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• 2014

Purpose: The purpose of this study was to evaluate the frequency of troughing and stress fracture, which are the major complications of scarf osteotomy, and to suggest methods to prevent these complications. Materials and Methods: We reviewed 243 cases of 137 patients treated with the scarf osteotomy for hallux valgus from January 2005 to December 2012. The mean follow-up period was 2.8 years. During the scarf osteotomy, a long oblique longitudinal osteotomy was performed in order to decrease the possibility of troughing and stress fracture. Radiographs of lateral view of the foot were obtained and the thicknesses of the first metatarsal base at the sagittal plane were measured and compared. Results: There was no troughing during fragment translation and screw fixation intraoperatively. Radiographs of lateral view of the foot taken preoperatively and at the last follow-up showed that the mean thickness of the first metatarsal was 22.4 mm preoperatively and 21.6 mm at the last follow-up, with a mean difference of 0.8 mm. And no stress fracture was observed. Conclusion: To prevent troughing and stress fracture, a long oblique longitudinal cut, parallel to the first metatarsal plantar surface, was performed, making both ends of the proximal segment truncated cone-shape, and securing the strong bony strut of the proximal segment. No troughing or stress fracture was experienced with scarf osteotomy.

• Advances in pediatric surgery
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• v.13 no.1
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• pp.61-65
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• 2007

Conventional treatment of Hirschsprung's disease consists of initial colostomy followed by pull-through operation. But, the treatment of Hirschsprung's disease has been changed along with the development of new surgical technique. Since 1995, endo-GIA has been available at our hospital and one stage Duhamel operation has been performed for neonatal Hirschsprung's disease. Between May 1995 and April 2006, 26 neonates have been treated with one stage pull-through operation by one pediatric surgeon at HanYang University Hospital. The sex ratio was 4.2:1 with male predominance. Clinical findings included abdominal distension (96.2 %), vomiting (50.0 %), delayed passage of meconium (46.2 %), constipation (23.1 %), and enterocolitis (15.4 %). Twenty two cases (84.6 %) were short-segment and 4 cases (15.4 %) were long-segment disease, of which 2 cases were total colon aganglionosis. One of the two patients with total colonic aganglionosis had double transition zones - distal ileum and hepatic flexure of the colon. The average age at operation was $14.56{\pm}8.77$ days and the average weight at operation was $3.26{\pm}0.66kg$. Primary Duhamel operations were performed in 25 patients and Soave-Boley operations was performed in one patient. The endo-GIA 35 (Ethicon, USA) was used from 1995 until 1997, and after that endo-GIA 60 (USSC, USA) was used. The average Duhamel operation time was $88.57{\pm}22.80$ minutes. Wound abscess (n = 2) and septum formation (n =1) occurred after Duhamel operation. Bowel function was normalized in 59 % within 3 months and in 95% within 1 year after operation. There was no mortality after one stage pull-through operation in neonate.

• BMB Reports
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• v.43 no.4
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• pp.279-283
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• 2010

Polydnavirus genome is segmented and dispersed on host wasp chromosome. After replication, the segments form double- stranded circular DNAs and embedded in viral coat proteins. These viral particles are delivered into a parasitized host along with parasitoid eggs. A serine-rich protein (SRP) is predicted in a polydnavirus, Cotesia plutellae bracovirus (CpBV), genome in its segment no. 33 (CpBV-S33), creating CpBV-SRP1. This study explored its expression and physiological function in the diamondback moth, Plutella xylostella, larvae parasitized by C. plutellae. CpBV-SRP1 encodes 122 amino acids with 26 serines and several predicted phosphorylation sites. It is persistently expressed in all tested tissues of parasitized P. xylostella including hemocyte, fat body, and gut. Its physiological function was analyzed by injecting CpBV-S33 and inducing its expression in nonparasitized P. xylostella by a technique called SERI (segment expression and RNA interference). The expression of CpBV-SRP1 significantly impaired the spreading behavior and total cell count of hemocytes of treated larvae. Subsequent RNA interference of CpBV-SRP1 rescued the immunosuppressive response. This study reports the persistent expression of CpBV-SRP1 in a parasitized host and its parasitic role in suppressing the host immune response by altering hemocyte behavior and survival.

• The Research Journal of the Costume Culture
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• v.18 no.6
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• pp.1138-1152
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• 2010

The purposes of this study are to segment women consumers on the basis of clothing shopping orientation and to investigate clothing purchasing behaviors of each segmented group by age variable for development of effective fashion marketing strategies to meet very changeable modern consumers' needs. The research methodology is survey and subjects were 650 women aged from 20s to 60s. The questionnaire consist of measurement items for clothing shopping orientation, clothing purchasing behaviors and subjects' demographic attributions. The data were analyzed by Cronbach's ${\alpha}$, factor analysis, cluster analysis, $x^2$ test, ANOVA and Duncan's multiple range test, using SPSS program. The results are as follows. First, 5 factors were emerged on clothing shopping orientation. Second, women consumers are segmented into 4 types(conspicuous, convenient, pleasurable, and unconcerned type) by clothing shopping orientation. Third, each consumer type divided by age variable showed some important differences on demographic characteristics and various clothing purchasing behaviors. Therefore, the results of this study support that clothing shopping orientation can be useful as one of the effective differentiated variables to segment women consumer market and age variable has important mediate effects on the differences of clothing purchasing behaviors by clothing shopping orientation type.

• Membrane Journal
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• v.15 no.1
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• pp.44-51
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• 2005

Polyurethane-polysiloxanes (PU/PDMS) was synthesized using 4,4'-diphenylmethane diisocyanate (MDI) and 1,4-butanediol (BD) to overcome the weakness to the organic chemicals. The composite membranes were prepared onto porous poly(tetrafluoroethylene) (PTFE) supports. In vapor permeation experiments, the flux increased with increasing operating temperatures and feed concentrations while the separation factors showed the opposite trend, so-called 'trade-off'. In this study, the effect of the flux on the operating temperatures was not severe since the content of the soft segments is fairly higher than that of the hard segments. The composite membrane type of PU/PDMS maintained high flux and separation factor as well when comparing with the dense type membranes.

• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.205-212
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• 1987

To examine the morphogenetic response, stem segments of 8 Populus spp. and 3 different explants of P. nigra var. italica were cultured on MS (Murashige and Skoog 1962) and WPM (Woody Plant Medium) medium containing various phytohormones. The results obtained were as follows: 1. Shoot regeneration and development from stem segment of 8 Populus spp. showed a quite difference according to the section and the species. All of the species of Leuce and Tacamahaca section did not form adventitious buds, while most of explants showed axillary or dormant bud elongation after 4 weeks. But P. nigra var. italica of Aigeiros section showed a successful adventitious bud formation (mean 5.4 buds per explant). 2. Leaf, petiole, and internode segment of P. nigra var. italica showed a quite differences according to media and ex plants upon the morphogenetic response. Adventitious bud formation from leaf was more abundant and readily initiated on the abaxial side than on the adaxial side. Mean number of 103 adventitious buds per explant was obtained from abaxial side of leaf segment cultured on WPM medium containing $0.2mg/{\ell}$ BAP for 5 weeks. 3. 2,4-D (2,4-dichlorophenoxy acetic acid) supplemented to media appeared to be negative upon the adventitious bud formation of P. nigra var. italica, while it promoted callus formation from all explants. Especially, NAA (${\alpha}$-naphtalene acetic acid) or NAA combination with BAP (6-benzylaminopurine) promoted root regeneration from the all explant of P. nigra var. italica in this study.

• Journal of Korean Neurosurgical Society
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• v.51 no.1
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• pp.20-23
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• 2012

Objective : To compare radiographic analysis on the sagittal lumbar curve when standing, sitting on a chair, and sitting on the floor. Methods : Thirty asymptomatic volunteers without a history of spinal pathology were recruited. The study population comprised 11 women and 19 men with a mean age of 29.8 years. An independent observer assessed whole lumbar lordosis (WL) and segmental lordosis (SL) between L1 and S1 using the Cobb's angle on lateral radiographs of the lumbar spine obtained from normal individuals when standing, sitting on a chair, and sitting on the floor. WL and SL at each segment were compared for each position. Results : WL when sitting on the floor was reduced by 72.9% than the average of that in the standing position. Of the total decrease in WL, 78% occurred between L4 to S1. There were significant decreases in SL at all lumbar spinal levels, except L1-2, when sitting on the floor as compared to when standing and sitting on a chair. Changes in WL between the positions when sitting on a chair and when sitting on the floor were mostly contributed by the loss of SL at the L4-5 and L5-S1 levels. Conclusion : When sitting on the floor, WL is relatively low; this is mostly because of decreasing lordosis at the L4-5 and L5-S1 levels. In the case of lower lumbar fusion, hyperflexion is expected at the adjacent segment when sitting on the floor. To avoid this, sitting with a lordotic lumbar curve is important. Surgeons should remember to create sufficient lordosis when performing lower lumbar fusion surgery in patients with an oriental life style.

• Korean Journal of Applied Biomechanics
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• v.15 no.3
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• pp.143-152
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• 2005

The purpose of this study was to predict the failure or success of the Snatch-lifting trial as a consequence of the stand-up phase simulated in Kane's equation of motion that was effective for the dynamic analysis of multi-segment. This experiment was a case study in which one male athlete (age: 23yrs, height: 154.4cm, weight: 64.5kg) from K University was selected The system of a simulation included a multi-segment system that had one degree of freedom and one generalized coordinate for the shank segment angle. The reference frame was fixed by the Nonlinear Trans formation (NLT) method in order to set up a fixed Cartesian coordinate system in space. A weightlifter lifted a 90kg-barbell that was 75% of subject's maximum lifting capability (120kg). For this study, six cameras (Qualisys Proreflex MCU240s) and two force-plates (Kistler 9286AAs) were used for collecting data. The motion tracks of 11 land markers were attached on the major joints of the body and barbell. The sampling rates of cameras and force-plates were set up 100Hz and 1000Hz, respectively. Data were processed via the Qualisys Track manager (QTM) software. Landmark positions and force-plate amplitudes were simultaneously integrated by Qualisys system The coordinate data were filtered using a fourth-order Butterworth low pass filtering with an estimated optimum cut-off frequency of 9Hz calculated with Andrew & Yu's formula. The input data of the model were derived from experimental data processed in Matlab6.5 and the solution of a model made in Kane's method was solved in Matematica5.0. The conclusions were as follows; 1. The torque motor of the shank with 246Nm from this experiment could lift a maximum barbell weight (158.98kg) which was about 246 times as much as subject's body weight (64.5kg). 2. The torque motor with 166.5 Nm, simulated by angular displacement of the shank matched to the experimental result, could lift a maximum barbell weight (90kg) which was about 1.4 times as much as subject's body weight (64.5kg). 3. Comparing subject's maximum barbell weight (120kg) with a modeling maximum barbell weight (155.51kg) and with an experimental maximum barbell weight (90kg), the differences between these were about +35.7kg and -30kg. These results strongly suggest that if the maximum barbell weight is decided, coaches will be able to provide further knowledge and information to weightlifters for the performance improvement and then prevent injuries from training of weightlifters. It hopes to apply Kane's method to other sports skill as well as weightlifting to simulate its motion in the future study.