• Journal of Korean Foot and Ankle Society
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• v.24 no.3
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• pp.107-112
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• 2020

Purpose: Hallux valgus (HV) is a common foot deformity that causes pain in the first metatarsophalangeal joint. Distal metatarsal osteotomies are commonly performed as a treatment. This retrospective study compared the clinical and radiological results of bioabsorbable magnesium (Mg) versus titanium (Ti) screw fixation for modified distal chevron osteotomy in HV. Materials and Methods: Forty-nine patients, who underwent modified distal chevron osteotomy for HV in 2018 and 2019, were reviewed retrospectively. Bioabsorbable Mg screw fixation was applied in 20 patients (22 feet), and a traditional Ti compression screw was applied in 29 patients (40 feet). The patients were followed up for at least six months. The clinical results were evaluated using the American Orthopaedic Foot and Ankle Society hallux metatarsophalangeal-interphalangeal (AOFAS-MTP-IP) scale and a visual analogue scale (VAS). The hallux valgus angle (HVA), intermetatarsal angle (IMA), and distal metatarsal articular angle (DMAA) were measured before, after surgery, and at the six months follow-up. Results: The AOFAS-MTP-IP scale and VAS points were improved in both groups, with no significant difference between them. At the six-month follow-up, HVA, IMA, and DMAA were similar. Bone union was confirmed in both groups, and there were no significant major complications in both groups. Four people in the Ti screw group underwent implant removal surgery. Conclusion: Bioabsorbable Mg screws showed comparable clinical, radiologic results to Ti standard screws six months after distal modified chevron osteotomy. These screws are an alternative fixation material that can be used safely and avoid the need for implant removal operations.

• Journal of Pharmacopuncture
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• v.12 no.1
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• pp.43-51
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• 2009

Objective : The purpose of this study is to present the standard for practical application of ginger herbal pharmacopuncture Material and Methods : We refer to ancient literatures and the recent papers for ginger. Conclusions : The following results have been obtained 1. The effect of ginger(Zingiber officinale Roscoe) is to "release exterior", "balance nutrient & defensive qi", "resolve phlegm", "arrest coughing", "warm the lungs". So ginger herbal pharmacopuncture can be applied to treating fever, chilling sign, headchae, snuffle and gasping cough due to cold affection and treating the symptoms like sputum and asthma that be revealed by pulmonary disease. 2. The effect of ginger is to "warm spleen and stomach", "arrest vomiting" "promote normal flow of water". So ginger herbal pharmacopuncture can be applied to treating nausea, vomiting, abdominal distension and diarrhea due to phlegm & dampness and treating edema. 3. The effect of ginger is to eliminate blood stasis. So ginger herbal pharmacopuncture can be applied to treating contusion, blood stasis, sprain and gynecologic disease. 4. Ginger can treat myalgia and pain due to wind-damp and have anti-inflammatory effect in pharmacology. So ginger herbal pharmacopuncture can be applied to treating disease of joint, ligament and muscle. 5. Ginger can resolve phlegm and resuscitate. So ginger herbal pharmacopuncture can be applied to treating unconsciousness. But, treating incipient cardiovascular accident, it needs to call your special attention to the danger of blood pressure increase. 6. In pharmacology, ginger is effective for antitumor, antioxidant effects and activating immunocyte. So ginger herbal pharmacopuncture can be applied to treating broadly varieties of tumor and allergic disease.

• Steel and Composite Structures
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• v.39 no.4
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• pp.401-417
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• 2021

This study experimentally reveals the influence of welding on grade S690Q high strength steel (HSS) butt joints from both micro and macro levels. Total eight butt joints, taking plate thickness and welding heat input as principal factors, were welded by shielded metal arc welding. In micro level, the microstructure transformations of the coarse grain heat affected zone (CGHAZ), the fine grain heat affected zone (FGHAZ) and the tempering zone occurred during welding were observed under light optical microscopy, and the corresponding mechanical performance of those areas were explored by micro-hardness tests. In macro level, standard tensile tests were conducted to investigate the impacts of welding on tensile behaviour of S690Q HSS butt joints. The test results showed that the main microstructure of S690Q HSS before welding was tempered martensite. After welding, the original microstructure was transformed to granular bainite in the CGHAZ, and to ferrite and cementite in the FGHAZ. For the tempering zone, some temper martensite decomposed to ferrite. The performed micro-hardness tests revealed that an obvious "soft layer" occurred in HAZ, and the HAZ size increased as the heat input increased. However, under the same level of heat input, the HAZ size decreased as the plate thickness increased. Subsequent coupon tensile tests found that all joints eventually failed within the HAZ with reduced tensile strength when compared with the base material. Similar to the size of the HAZ, the reduction of tensile strength increased as the welding heat input increased but decreased as the thickness of the plate increased.

• Journal of the Earthquake Engineering Society of Korea
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• v.27 no.5
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• pp.203-211
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• 2023

For fast-built and safe precast concrete (PC) construction, the dry mechanical splicing method is a critical technique that enables a self-sustaining system (SSS) during construction with no temporary support and minimizes onsite jobs. However, due to limited experimental evidence, traditional wet splicing methods are still dominantly adopted in the domestic precast industry. For PC beam-column connections, the current design code requires achieving emulative connection performances and corresponding structural integrity to be comparable with typical reinforced concrete (RC) systems with monolithic connections. To this end, this study conducted the standard material tests on mechanical splices to check their satisfactory performance as the Type 2 mechanical splice specified in the ACI 318 code. Two PC beam-column connection specimens with dry mechanical splices and an RC control specimen as the special moment frame were subsequently fabricated and tested under lateral reversed cyclic loadings. Test results showed that the seismic performances of all the PC specimens were fully comparable to the RC specimen in terms of strength, stiffness, energy dissipation, drift capacity, and failure mode, and their hysteresis responses showed a mitigated pinching effect compared to the control RC specimen. The seismic performances of the PC and RC specimens were evaluated quantitatively based on the ACI 374 report, and it appeared that all the test specimens fully satisfied the seismic performance criteria as a code-compliant special moment frame system.

• 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 the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.570-576
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• 2018

In reinforced concrete structures, the joints of ordinary rebars are usually lap joints, which are bound by binding wires with rebars, and mechanical joints by couplers. In domestic design standards (concrete design code), welded lap joints are restricted for ordinary rebars, but overseas standards allow welded lap joints of ordinary rebars through pre-heating. This study investigated the domestic and international standards/criteria and evaluated the fracture strength by performing the tensile test on the lap welded joint of SD400 grade rebars, which is used the most in the construction sites. The weld length of the specimen for weld lap joints is based on the minimum weld length (8d) given in the KS standard (KS B ISO 17660-1). According to AWS D1.4, the preheating temperature was set to $150^{\circ}C$ for D19 and below, and $260^{\circ}C$ for D22 and above. In the test results, the tensile strength of rebars with welded lap joints exceeded the required strength (125% of the yield strength) according to the concrete design code. To analyze the effect of preheating, the tensile strength of the welded rebars after preheating was not significantly different from that of the welded rebars without preheating. The carbon equivalent content (Ceq) of the rebars used in the test was 0.45% or less. Under AWS D1.4, no preheating is required if the carbon equivalent is less than 0.45%. All specimens with a welded lap length of 8d failed by a bar fracture. The effect of preheating was confirmed to be insignificant due to the low carbon equivalent of the rebar.

• Journal of radiological science and technology
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• v.29 no.4
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• pp.225-228
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• 2006

Purpose: Accurate clinical evaluation of the alignment of the calcaneus relative to the tibia in the coronal plane is essential in the evaluation and treatment of hindfoot pathologic condition. Previously described standard anteroposterior, lateral, and oblique radiographic methods of the foot or ankle do not demonstrate alignment of the tibia relation to the calcaneus in the coronal plane. The purpose of this study was to introduce hindfoot coronal alignment view. Material : 1) Both feet were imaged simultaneously on an elevated, radiolucent foot stand equipment. 2) Both feet stood on a radiolucent platform with equal weight on both feet. 3) Both feet are located foot axis longitudinal perpendicular to the platform. 4) Silhouette tracing around both feet are made, and line is then drawn to bisect the silhouette of the second toe and the outline of the heel. 5) The x-ray beam is angled down approximately $15^{\circ} to $20^{\circ} Result : 1) This image described tibial axis and medial, lateral tuberosity of calcaneus. 2) Calcaneus do not rotated. 3) The view is showed by talotibial joint space. Conclusion: Although computed tomographic and magnetic resonance imaging techniques are capable of demonstrating coronal hindfoot alignment, they lack usefulness in most clinical situations because the foot is imaged in a non-weight bearing position. But hindfoot coronal alignment view is obtained for evaluating position changing of inversion, eversion of the hindfoot and varus, valgus deformity of calcaneus.

• The korean journal of orthodontics
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• v.9 no.1
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• pp.85-98
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• 1979

This investigation was designed to compare the craniofacial and dental morphology of class III malocclusion with that of normal occlusin in children, and to determine the incidence of various class III craniofacial skeletal patterns. The material selected for this study consisted in standard lateral cephalograms of eighty two Korean children, forty one boys and forty one girls, aged 10 through 12 years, having class III malocclusion, and forty two Korean children, twenty boys and twenty two girls, with normal occlusion in the same age. Using the tracings of the standard lateral cephalograms, various angular and linear measurements were recorded, tabulated and statistically analyzed, and then the class III craniofacial skeletal morphology was divided into various patterns by the degree of SNA and SNB, which respectively were below, within or beyond the normal range of those of normal occlusion. The following characteristics of the craniofacial and dental morphology of class III malocclusion were observed. 1. The cranial base length of class III malocclusion was smaller than that of normal occlusion, and the small saddle angle was a characteristic figure of class III malocclucion. 2. Maxillary length of class III malocclusion was smaller than that of normal occlusion, and point A was retropositioned relative to cranial base but not PNS in class III malocclusion. Maxillary base inclination was not significantly different between the two, but occlusal plane to palatal plane was small in class III malocciusion. 3. The mandibular body length shown no difference between the two, but the mandibular body positioned anteriorly relative to cranial base in class III malocclusion. Ramus height, gonial angle, and mandibular effective length were large in class III malocclusion. Mandibular plane angle and joint angle had no difference between the two, and occlusal plane to mandibular plane angle was large in class III malocclusion. 4. Maxillary incisor inclination was not significantly different between class III malocclusion and normal occlusion, but mandibular incisors positioned and inclined lingually and consequently interincisal angle was large in class III malocclusion. 5. Class III malocclusion was divided into six categories of craniofacial skeletal pattern. The most common class III pattern was found to be one in which the maxilla was within the normal range of prognathism while the mandible extended beyond this range. The pattern in which the maxilla was below the normal range of prognathism while the mandible was within this range was approximately one fifth of the class III sample.

• Journal of Korean Society of Steel Construction
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• v.16 no.4 s.71
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• pp.407-414
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• 2004

Bridges in common use are expected to have more varieties of load in their connected members and bolts than in construction. Faults in connection members or bolts occur so often according to the time flow. One of the purposes of this study is to find out the behavior and structural features of high-tension bolted joints with faults that are very difficult and cost much to find out through experimentation with finite element analysis. Another purpose of this study is to provide sufficient data, estimated experimental results, and the scheme of the test plate for an economical experimental study in the future. Surveys of bridges with a variety of faults and statistical classifications of their faults were performed, as was a finite element analysis of the internal stress and the sliding behavior of standard and defective bridge models. The finite element analysis of the internal stress was performed according to the interval of the bolt, the thickness of the plate, the distance of the edge, the diameter of the bolt, and the expansion of the construction. Furthermore, the analysis explained the sliding behavior of high-tension bolt joints and showed the geometric non-linear against the large deformation, and the boundary non-linear against the non-linear in the contact surface, including the material non-linear, to best explain the exceeding of the yield stress by sliding. A normally bolted high-tension bolt joint and deduction of bolt tension were also analyzed with the finite element analysis of bridge-sliding behavior.

• Journal of Chest Surgery
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• v.32 no.7
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• pp.653-659
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• 1999

Background: Despite the recent promising efforts to improve survival in patients with esophageal carcinoma, the long term survival results of patients with esophageal cancer have seldom been reported in Korea. To establish standard control for future studies, we re trospectively analyzed the surgical treatment results of the esophageal cancer patients managed in our department at Seoul National University Hospital. Material and Method: From January 1984 to December 1996, 734 patients were diagnosed with esophageal cancer. Among them, 253 patients underwent surgery in our department. We retrospectively analyzed the operative results and long term survival rates of these patients. Result: The majority of patients(237) had squamous cell histology and only 6 patients had adenocarcinoma. The final TNM stage grouping for these patients was based on the 1988 revised American Joint Commitee on Cancer classification. Twenty one patients were surgically classified as stage I, 109 as stage II, and 107 as stage III. C respiratory failure in 8, sepsis in 1, hepatic failure in 1, bleeding in 1 and unknown etiology in the remaining 3. The actuarial survival of 222 patients in whom the curative resection was accomplished at 1-, 2-, 3- and 5 years was 74.7${\pm}$3.1%, 46.5${\pm}$3.7%, 32.3${\pm}$3.7%, and 19.9${\pm}$3.3%, respectively. CONCLUSION: The poor long term survival rates suggest that an alternative treatment method such as intensive combined modality therapy should be developed for the management of esophageal cancer.