• Steel and Composite Structures
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• v.47 no.2
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• pp.203-216
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• 2023

The composite beam connections often encountered fracture failure in the welded bottom flange joint, and a bottom flange bolted connection has been proposed to increase the deformation ability of the bottom flange joint. The seismic performance of the bottom flange bolted composite beam connection was suffered from both the composite action of concrete slab and the asymmetric load transfer mechanisms between top and bottom beam flange joints. Thus, this paper presents a comprehensive numerical study on the working mechanism of the bottom flange bolted composite beam connections. Three available modelling methods and a new modelling method on the flange-stud-slab interactions were compared. The efficient numerical modeling method was selected and then applied to the parametric study. The influence of the composite slab, the bottom flange bolts, the shear composite ratio and the web hole shape on the seismic performance of the bottom flange bolted composite beam connections were investigated. A hogging strength calculation method was then proposed based on numerical results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.12
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• pp.1563-1571
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• 2011

In this study, we developed a finite element model of the human middle ear has been developed to calculate itsfor sound transfer characteristics calculation. We usedThe geometric data forof ossicles, obtained byfrom micro-CT scanning, was used in order to develop the middle- ear FE model. A right- side temporal bone of a Korean cadaver was used for the micro-CT scanning. The developed FE model includes three ossicles, the tympanic membrane, ligaments, and muscles. We calculated theA sound transfer function from the tympanic membrane to the stapes footplate was calculated. The sound transfer function calculated vias of the FE model shows good agreement with measured responses over the 10- kHz frequency band. To measureidentify the sensitivityies of the middle- ear function due to material property variation, we studied several parameters studies have been fulfilled using the middle ear FE model. TAs a result the stiffness property of the incudostapedial joint had the greatest influence onwas the most influential to the middle- ear sound transfer function among the parameters.

• Clinics in Shoulder and Elbow
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• v.22 no.4
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• pp.220-226
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• 2019

Background: This retrospective study was undertaken to evaluate mid-term clinical and radiological outcomes of lattisimus dorsi (LD) tendon transfer in patients with irreparable massive rotator cuff tears (MRCT). We hypothesize that LD tendon transfer would provide safe and satisfactory clinical outcomes at mid-term follow-up. Methods: From November 2008 to December 2016, 23 patients ($57.5{\pm}4.4years$; 20 male, 3 female) who underwent LD tendon transfer for massive tears, were enrolled. Inclusion criteria were irreparable MRCT. Exclusion criteria included full thickness subscapularis tear, rotator cuff arthropathy, anterosuperior rotator cuff tear, and osteoarthritis. Mean follow-up period was $4.7{\pm}4.0years$ (range, 2-12 years). Clinical assessment (American Shoulder and Elbow Surgeons [ASES], University of California, Los Angeles [UCLA], Simple Shoulder Test [SST]) and radiographic assessment (osteoarthritis [OA], acromiohumeral distance [AHI]) were evaluated. Results: ASES, UCLA and SST scores, and range of motion (ROM), except internal rotation, improved significantly at the last followup (p<0.05). Also, AHI was significantly improved at the last follow-up, from 6.6 mm to 8.2 mm (p=0.008). At the final follow-up, the radiologic stages of the glenohumeral osteoarthritis were determined as stage 1 in 9 patients, stage 2 in 10 patients, stage 3 in 2 patients, and stage 4 in 2 patients. Complications were observed in 21.7% cases: 3 re-tears and 2 infections were noted in our study. Conclusions: LD tendon transfer for irreparable MRCT provides satisfactory clinical outcomes at mid-term follow-up. Mild degenerative osteoarthritis (stage 1, 2) of the shoulder joint are common at the mid-term follow-up. Also, complications such as tear, infection should be considered.

• Earthquakes and Structures
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• v.26 no.5
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• pp.383-400
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• 2024

For a conventionally repaired frame-supported-transfer-slab (FSTS) reinforced concrete (RC) structure, both the transfer slab and the beam-to-column and transfer slab-to-column joints remain vulnerable to secondary earthquakes. Aimed at improving the seismic performance of a damaged FSTS RC structure, an innovative retrofitting scheme is proposed, which adopts the sector lead rubber dampers (SLRDs) at joints after the damaged FSTS RC structure is repaired by conventional approaches. In this paper, a series of quasi-static cyclic tests was conducted on a large-scale retrofitted FSTS RC structure. The seismic performance was evaluated and the key test results, including deformation characteristics, damage pattern, hysteretic behaviour, bearing capacity and strains on key components, were reported in detail. The test results indicated that the SLRDs started to dissipate energy under the service level earthquake, and thus prevented damages on the beam-to-column and transfer slab-to-column joints during the secondary earthquakes and shifted the plastic hinges away from the beam ends. The retrofitting scheme of using SLRDs also achieved the seismic design concept of 'strong joint, weak component'. The FSTS RC structure retrofitted by the SLRDs could recover more than 85% bearing capacity of its undamaged counterpart. The hysteresis curves were featured by the inverse "S" shape, indicating good bearing capacity and hysteresis performance. The deformation capacity of the damaged FSTS RC structure retrofitted by the SLRDs met the corresponding codified requirements for the case of the maximum considered earthquake, as set out in the Chinese seismic design code. The stability of the FSTS RC structure retrofitted by the SLRDs, which was revealed by the developed stains of the RC frame and transfer slab, was improved compared with the undamaged FSTS RC structure.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.4
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• pp.276-283
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• 2013

Purpose: The purpose of this study was to investigate the fit and screw joint stability between Ready-made abutment and CAD-CAM custom-made abutment. Materials and methods: Osstem implant system was used. Ready-made abutment (Transfer abutment, Osstem Implant Co. Ltd, Busan, Korea), CAD-CAM custom-made abutment (CustomFit abutment, Osstem Implant Co. Ltd, Busan, Korea) and domestically manufactured CAD-CAM custom-made abutment (Myplant, Raphabio Co., Seoul, Korea) were fabricated five each and screws were provided by each company. Fixture and abutments were tightening with 30Ncm according to the manufacturer's instruction and then preloding reverse torque values were measured 3 times repeatedly. Kruskal-Wallis test was used for statistical analysis of the preloading reverse torque values (${\alpha}=.05$). After specimens were embedded into epoxy resin, wet cutting and polishing was performed and FE-SEM imaging was performed, on the contact interface. Results: The pre-loading reverse torque values were $26.0{\pm}0.30Ncm$ (ready-made abutment; Transfer abutment) and $26.3{\pm}0.32Ncm$ (CAD-CAM custom-made abutment; CustomFit abutment) and $24.7{\pm}0.67Ncm$ (CAD-CAM custom-made abutment; Myplant). The domestically manufactured CAD-CAM custom-made abutment (Myplant abutment) presented lower pre-loading reverse torque value with statistically significant difference than that of the ready-made abutment (Transfer abutment) and CAD-CAM custom-made abutment (CustomFit abutment) manufactured from the same company (P=.027) and showed marginal gap in the fixture-abutment interface. Conclusion: Within the limitation of the present in-vitro study, in domestically manufactured CAD-CAM custom-made abutment (Myplant abutment) showed lower screw joint stability and fitness between fixture and abutment.

• Journal of Global Scholars of Marketing Science
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• v.18 no.4
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• pp.277-306
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• 2008

Knowledge1 is considered to be a key element of understanding how organizations gain and sustain competitive advantages. But very few firms are capable of creating the requisite knowledge and thus, firms should acquire and exploit new knowledge through knowledge transfer processes. The empirical part of this study involves examining relationships among adaptability of knowledge and knowledge transfer and marketing performance and testing the moderating roles of absorptive capacity, socialization and local marketing knowledge. This study is organized as follows: (1) Previous literature on knowledge, knowledge transfer and absorptive capacity is summarized, followed by the development of hypotheses derived from the knowledge-based view and absorptive capacity. (2) The hypotheses are tested with data collected from MNCs' subsidiaries performing marketing activities in Korea.Thestudyisclosedwithfindings,implications,andconclusions. Following six research hypotheses are drawn from literature review in related areas: H1: Adaptability of knowledge transferred from the MNCs' headquarters and other subsidiaries is positively associated with knowledge inflows into the receiving subsidiary. H2: The level of marketing knowledge transferred from the MNCs' headquarters and other subsidiaries is positively associated with marketing performance of the receiving subsidiary. H3: Increases in potential absorptive capacity will enhance the relationship between adaptability of knowledge and the level of marketing knowledge transfer. H4: Increases in realized absorptive capacity will enhance the relationship between the level of knowledge transfer and marketing performance of the receiving subsidiary. H5: Increases in socialization activity among the headquarters and subsidiaries will enhance the relationship between adaptability of knowledge and the level of marketing knowledge transfer. H6: Increases in the level of locally developed marketing knowledge will enhance the relationship between the level of knowledge transfer and marketing performance of the receiving subsidiary. The research framework that illustrates the proposed hypotheses is presented in figure 1. The unit of analysis for this study is knowledge transfer from the MNCs' headquarters and other subsidiaries to their subsidiaries operating in South Korea. The population for this study consists of subsidiaries established either as joint ventures or as wholly-owned subsidiaries. A group of 603 foreign firms were drawn from diverse industry organizations and business societies. After personal contact, telephone, fax, and e-mail to request that the respondents complete the questionnaire, 282 valid questionnaires from 133 initial sample companies were collected. The results of the empirical analyses significantly support all of the proposed hypotheses except hypothesis 3. Adaptability of external knowledge promotes knowledge transfer and the relationship is moderated by a firm's potential knowledge absorptive capacity. On the other hand, knowledge transfer improves a firm's marketing performance and a firm's realized knowledge absorptive capacity and local marketing knowledge moderate the relationship. The theoretical and practical implications of the findings in this study are as follows: (1) firms must take seeking, transferring, sharing and exploiting of external knowledge into serious consideration, while simultaneously creating knowledge to support the necessary business operations, remain competitive, and achieve superior performance. (2) Firms should continuously seek to develop their knowledge absorptive capacity (both potential and realized capacity) to absorb, learn and utilize valuable external knowledge. (3) Firms should emphasize not only absorptive capacity, but also development of local knowledge. Firms with strong absorptive capability and local knowledge can learn and transfer more external knowledge, which can be translated into greater levels of competence and performance.

• Journal of Welding and Joining
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• v.32 no.4
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• pp.1-9
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• 2014

A quantitative understanding on the effect of the welding conditions on weld joint dimensions and weld thermal cycle is difficult through experimental studies alone. The experimental realization of temperature distribution in the weld pool is proved to be extremely difficult due to the small size of welds, high peak temperature and steep temperature gradients in weld pool. This review deals with the heat transfer and fluid flow analysis to understand the parametric influence of a single wire submerged arc welding (SAW) and multi-wire SAW processes on the weld bead dimensions, temperature and fluid flow distribution in the weldment.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.271-274
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• 2005

Existing strut-and-tie model cannot be applied to analysis of slender beams without shear reinforcement because shear transfer mechanism is not formed. In the present study, a new strut-and-tie model with rigid joint was developed. Basically, concrete strut is modeled as a frame element which can transfer shear force (or moment) as well as axial force. Employing Rankine failure criterion, failure strength due to shear-tension and shear-compression developed in compressive concrete strut was defined. For verification, various test specimens were analyzed and the results were compared with tests. The proposed strut-and-tie model predicted shear strength and failure displacement with reasonable precision, addressing the design parameters such as shear reinforcement, concrete compressive strength, and shear span ratio.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.207-210
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• 2003

As reviewing of current trend on PC connection details, owing to effective stress transfer in the connection, it grow to increase that use of mechanical splices, reinforcements or welded splices, and prestressing. However such devices as reinforcement, mechanical splices entail not only more cost resulted from materials but also extra construction process so as to cause PC used method to lower competition against conventional method. Therefore more enhanced connection details which help working process simplified and construction cost reduced. In this research, as replace 9.3mm 7strand for reinforcement, it is attempt to devise connection detail which makes workability improve and confirm effective stress transfer in the region of connection. The experimental research is proceeded by partial tension test of specimen. The splice lengths of 7strand is decided to be variations. The flexural capability is verified to depend on spice length. An an appropriate splice length could be also determined as a precedent research on improving PC connection detail.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.20-24
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• 1997

In general, pantograph type manipulators are used for carrying heavy payloads with positional accuracy. In this paper, a double pantograph type manipulator, activated by two slider joints, is studied for applying to file handing machine in atomic power plant. In order to realize the stable horizontal movement of a heavy fuel rod whit good positional accuracy, methods for allocating slider and finding constant joint rates are proposed. In addition, the static deflection of the proposed mechanism was studied using transfer-stiffness matrix method. A neural network control algorithm which compensates static deflections is explored with computer simulations.