• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.127-131
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• 2006

There are being a lot of studies for achievement of high speed Dehydration, high-strength and Lightweight of washing machine in the latest washing machine business. It is essential that Press-joining Strength of Spin Drum Seaming division is improved .to attain that target. Generally, we are using Mechanical press-joining by Seaming and T.I.G (Tungsten Inert Gas) welding among part joint method. Mechanical press-joining method that is mainly using for Stainless Steel (STS430) Drum have lots of merit that consumption of energy is low more than welding and production costs cut down and generation of the corrosion is solved by removing weld zone defect and materials having different properties are enable to join without special equipment. But, it is difficult to realize joint strength required at high speed operation because joint strength of mechanical press-joining method is low remarkably in comparison with welding. Also, there are a lot of analysis difficulties and very limited research is under way due to the dynamic factor such as multistage plastic working, elastic recovery, residual stress etc. The results of this study show optimal joining condition for mechanical press-joining by performing lots of tensile joining strength test with various specimen under multi-change of important design factor such as seaming width, bead area and bead depth etc.

• International Journal of Highway Engineering
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• v.19 no.3
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• pp.11-18
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• 2017

PURPOSES : This study investigates the effect on concrete pavement accordance with the curing methods in cool weather and supports the best method in the field. METHODS : Two field tests evaluated the curing methods of concrete pavement in cool weather. Firstly, five curing methods were tested, including normal curing compound, black curing compound, bubble sheet, curing mat, and curing mat covered with vinyl. Concrete maturity was compared from temperature data. Secondly, normal curing compound and curing mat with vinyl, which showed the best performance, were compared in terms of maturity and join condition index. RESULTS:From the field tests, it is an evident that curing mat with vinyl accelerated the concrete strength. Therefore, it is possible to conduct saw-cut works in cool weather, which minimizes damage on concrete at joint. CONCLUSIONS : For concrete pavement in cool weather, using curing mat with vinyl as the curing method could overcome the strength delay. Therefore, strength and durability problems on concrete at joint due to cool weather would be fewer in the future.

• Journal of Oral Medicine and Pain
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• v.39 no.3
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• pp.100-106
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• 2014

Purpose: This study was performed to investigate the relationship between temporomandibular disorders (TMDs) and the asymmetry of the mandibular height. Methods: We compared 100 randomly selected TMD patients diagnosed by the research diagnostic criteria for TMD (RDC/TMD) Axis I with 100 non-TMD control subjects matched with the TMD patients in age and gender. The mandibular heights were measured on an orthopantomogram and the asymmetry index (AI) was calculated as previously described. Results: The absolute AI value of 4.37% turned out to be the least cut-off value defining asymmetry, which showed a significant difference in asymmetry incidence (p<0.01) between the TMD and control groups. The risk of TMD increased in the asymmetry group by 4.57 (odds ratio). The incidence of asymmetry was not related to age and gender in both of the TMD and control groups. When dividing the TMD group according to the RDC/TMD Axis I diagnosis, neither the incidence of muscle disorder nor disk displacement was related to the incidence of asymmetry. However, a higher incidence of asymmetry was observed in the subjects classified into the arthrosis/arthritis groups (p<0.01). Conclusions: Although it does not imply a direct cause-and-effect relationship, asymmetry resulting in more than 4.37% difference between mandibular heights may increase the risk of TMD and correlates positively to the incidence of arthritic change in the temporomandibular joint of TMD patients.

• Applied Microscopy
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• v.26 no.1
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• pp.11-16
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• 1996

This study was designed to observe the ultrastructure of synoviocytes which are concerned with phagocytic function in the knee joint of the human. The synovia were dissected and were fixed for two hours in 0.2% glutaraldehyde and 4% paraformaldehyde solution and processed and finally infused in 2.3 M sucrose and 20% PVP solution. The tissues were cut with the cryoultramicrotome and labelled with primary antibodies (anti-tubulin, anti-vimentin) and secondary antibody-6 nm colloidal gold particles. The tissues were observed under transmission electronmicroscope. The results were followings. 1. In phagocytic synovial cells, the distributions of tubulin were cytoplasm, especially around vacuoles. 2. In phagocytic synovial cells, the distributions of vimentin were cytoplasm. 3. Both tubulin and vimentin were not located inside of vacuoles. On the basis of above findings, it is obvious that the phagocytic functions are concerned with tubulin, and the phagocytic synovial cells contain vimentin.

• Laser Solutions
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• v.18 no.1
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• pp.1-6
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• 2015

High welding speed and narrow weld seam are favorable for welding of magnesium alloy. Magnesium alloy is recommended for the smart frame because it has several advantages such as low density, high thermal conductivity, EMI shielding capability and good cast ability. This study is for the assembly welding of the magnesium smart frame with high productivity, good performance and low cost. The window for battery on AZ91D frame produced by die-casting was prepared by CNC machining. Corresponding AZ31 blank of 0.2mm thickness was prepared by die-blanking cut. All system set was fixed at the stationary bed but the laser beam was manipulated by scanner up-to 1,000mm/s speed. The weld joint between AZ31 sheet and AZ91D frame was welded by fiber laser on 850~1,000W output power. The joint showed penetration enough but some humping bead. The distortion by the weld heat was almost free because of the quick dissipation of the heat by small beam size and fast welding. Consequently, the thinner magnesium foil was assembled successfully to the magnesium frame of mobile phone.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2202-2209
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• 2009

Joint paths are induced mathematically for many kinds of joint pattern between master- and sub-pipes. By compensating them with root gap of welds and kerf width, real cutting paths are determined. Their NC codes are generated, and the paths generated by NC code are verified by a ghost function. A beveling is implemented through tilting a torch in the A- and B-axis direction for 8 sections in the chuck rotation of C-axis. The effective CAM program was developed specially for 6-axis CNC pipe coasters which cut a master or sub- pipe along the cutting path and simultaneously fulfill a beveling process.

• Geomechanics and Engineering
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• v.13 no.6
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• pp.977-995
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• 2017

It is well accepted that rock failure mechanism influence the cutting efficiency and determination of optimum cutting parameters. In this paper, an attempt was made to research the factors that affect the failure mechanism based on discrete element method (DEM). The influences of cutting depth, hydrostatic pressure, cutting velocity, back rake angle and joint set on failure mechanism in rock-cutting are researched by PFC2D. The results show that: the ductile failure occurs at shallow cutting depths, the brittle failure occurs as the depth of cut increases beyond a threshold value. The mean cutting forces have a linear related to the cutting depth if the cutting action is dominated by the ductile mode, however, the mean cutting forces are deviate from the linear relationship while the cutting action is dominated by the brittle mode. The failure mechanism changes from brittle mode with larger chips under atmospheric conditions, to ductile mode with crushed chips under hydrostatic conditions. As the cutting velocity increases, a grow number of micro-cracks are initiated around the cutter and the volume of the chipped fragmentation is decreasing correspondingly. The crack initiates and propagates parallel to the free surface with a smaller rake angle, but with the rake angle increases, the direction of crack initiation and propagation is changed to towards the intact rock. The existence of joint set have significant influence on crack initiation and propagation, it makes the crack prone to propagate along the joint.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.3
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• pp.157-162
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• 2023

Elongated styloid syndrome (ESS) can present with myriad symptoms that mimic common features of orofacial pain, such as temporomandibular joint disorders (TMJDs), often causing a challenge and delay in diagnosis. We report the case of a 52-year-old male with a three-year history of non-painful clicking during jaw movement initially diagnosed as TMJD-related internal derangement. The patient presented with a history of annoying jaw sounds for three years, described as a popping sound without bilateral clicking or crepitation. Tinnitus and progressive hearing loss were observed in the right ear, and a hearing aid was recommended by an otolaryngologist. The patient was initially diagnosed with TMJD and managed accordingly; nevertheless, his symptoms persisted. Imaging revealed prominent bilateral styloid process elongation that exceeded the recognized cut-off level of >30 mm for elongation. The patient was informed of his diagnosis and its treatment but opted only for further swallowing and auditory assessments of his ear and nose symptoms. Clinicians should consider including ESS as a differential diagnosis in patients presenting with non-specific chronic orofacial symptoms for timely diagnosis and favorable clinical outcomes.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.2
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• pp.228-236
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• 2004

Two varieties of alfalfa (Medicago sativa L cv. Pioneer and Beaver) and timothy (Phleum pratense L cv. Climax and Joliette), grown at different locations in Saskatchewan (Canada), were cut at three stages [1=one week before commercial cut (early bud for alfalfa; joint for timothy); 2=at commercial cut (late bud for alfalfa; pre-bloom head for timothy); 3=one week after commercial cut (early bloom for alfalfa; full head for timothy)]. The energy values of forages were determined using three approaches, including chemical (NRC 2001 formula) and biological approaches (standard in vitro and in situ assay). The objectives of this study were to determine the effects of forage variety and stage of maturity on energy values under the climate conditions of western Canada, and to investigate relationship between chemical (NRC 2001 formula) approach and biological approaches (in vitro and in situ assay) on prediction of energy values. The results showed that, in general, forage species (alfalfa vs. timothy) and cutting stage had profound impacts, but the varieties within each species (Pioneer vs. Beaver in alfalfa; Climax vs. Joliette in timothy) had minimal effects on energy values. As forage maturity increased, the energy contents behaved in a quadratic fashion, increasing at stage 2 and then significantly decreasing at stage 3. However, the prediction methods-chemical approach (NRC 2001 formula) and biological approaches (in vitro and in situ assay) had great influences on energy values. The highest predicted energy values were found by using the in situ approach, the lowest prediction value by using the NRC 2001 formula, and the intermediate values by the in vitro approach. The in situ results may be most accurate because it is closest to simulate animal condition. The energy values measured by biological approaches are not predictable by the chemical approach in this study, indicating that a refinement is needed in accurately predicting energy values.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.318-326
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• 2013

The effect of finger joint location and distance from joint to joint one another on 3 point mid-concentration bending strength properties was investigated in this experiment. Resorcinol-phenol formaldehyde (RPF) and aqueous vinyl urethane (AVU) was used to domestic Pinus densiflora Sieb. et Zucc and imported Picea sitchensis Carr. that have been cut to different width of 0.15 mm between finger tip and root width and the distance from loading point to finger joint was 0, 30, 40, 50, 60 mm. The effect was not found on the location and distance of finger joint for bending modulus of elasticity, while the efficiency of bending strength property increased proportionally as the location of finger joint from the load point and the distance between finger joint increased. No influence was shown by finger joint location and distance beyond 3 times of specimen thickness, since similar values were shown between the solid wood and no destruction occurred materials.