• Journal of Korean Society of Steel Construction
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• v.18 no.3
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• pp.385-393
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• 2006

In Korea, the effective utilization of wod structure is encour aged to preserve natural resources and the global environment.ote demand for wod. The efective combination of structural la minated timber and other materials is expected to extend the potential of building structures. This research examines the moment resis tance-type jointing method using structural laminated timber and H-section stel aiming at development of the two-direction frame for lar ge 9 mm and 12 mm) of the H section. Therefore, we conducted the experiment with bending test of the joints to investigate the s tifnes, strength, strain distributions of laminated timber an d of the flange of the H section, and failure paterns. As shown in the results, t he joints with a flange thicknes of 9 mm and 12 m have superi or strength with a flange thicknes of 9 mm and 12 mm were very large, whic h confirmed the high level of energy absorption of such structure s.

• Journal of Korean Society of Steel Construction
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• v.18 no.3
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• pp.395-403
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• 2006

Recently constructed bridges often have long spans and simple structure details considering not only the function but other important factors such as aesthetics, maintenance, construction duration and life cycle cost. Therefore, bridges require high-performance steels like extra-thick plate steels and thermo-mechanical control process (TMCP) steels. TMCP stels are now gaining wide attention due to their weldability improved strength and toughness. Recently, SM570-TMC steel, which is a high-strength TMCP steel with a tensile strength of 600 MPa, has been developed and applied to steel structures. However, using this steel in building steel structures requires the elucidation of not only material characteristics but also the mechanical characteristic of welded joints. In this study, high-temperature tensile properties of SM570-TMC steel were investigated through the elevated temperature welded joints of SM570-TMC steel were studied through the three-dimensional thermal elasticplastic analyses on the basis of mechanical properties at high temperatures obtained from the experiment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.6
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• pp.2489-2499
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• 2011

As R&D cooperation activities with various partners are becoming huge in scale and scope, to achieve successful R&D performance, we need to systematically divide by its characteristics and to stratagemically carry out R&D cooperation activities. In this paper we propose R&D cooperation system between the university and the R&D institute in the geoscience field. The cooperation system can include activities of joint R&D program execution, R&D researcher exchange, R&D infrastructure use, technology commercialization and business exchange. Its system seems to positively affect on R&D performance and when considering the level of innovation as a moderating variable, in the situation of high innovation environment its system is able to positively affect on the R&D performance. For different effects of R&D cooperation activities on individual cooperation performance we can choose proper cooperation activities for R&D cooperation purposes.

• Smart Structures and Systems
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• v.6 no.4
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• pp.373-388
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• 2010

The updated finite element model of K$\ddot{o}$m$\ddot{u}$rhan Highway Bridge on the Firat River located on the $51^{st}$ km of Elazi$\breve{g}$-Malatya highway is obtained by using analytical and experimental results. The 2D and 3D finite element model of the bridge is created by using SAP2000 structural analyses software, and the dynamic characteristics of the bridge are determined analytically. The experimental measurements are carried out by Operational Modal Analysis Method under traffic induced vibrations and the dynamic characteristics are obtained experimentally. The vibration data are gathered from the both box girder and the deck of the bridge, separately. Due to the expansion joint in the middle of the bridge, special measurement points are selected when experimental test setups constitute. Measurement duration, frequency span and effective mode number are determined by considering similar studies in literature. The Peak Picking method in the frequency domain is used in the modal identification. At the end of the study, analytical and experimental dynamic characteristic are compared with each other and the finite element model of the bridge is updated by changing some uncertain parameters such as material properties and boundary conditions. Maximum differences between the natural frequencies are reduced from 10% to 2%, and a good agreement is found between natural frequencies and mode shapes after model updating.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9611-9614
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• 2014

Purpose: To investigate the clinical value in lung cancer of a combination of four serum tumor markers, haptoglobin (Hp), carcinoembryonic antigen (CEA), neuron specific enolase (NSE) as well as the cytokeratin 19 fragment (CYFRA21-1). Materials and Methods: Serum Hp (with immune-turbidimetric method), CEA, NSE, CYFRA21-1 (with chemiluminescence method) level were assessed in 193 patients with lung cancer, 87 patients with benign lung disease and 150 healthy controls. Differences of expression were compared among groups, and joint effects of these tumor markers for the diagnosis of lung cancer were analyzed. Results: Serum tumor marker levels in patients with lung cancer were obviously higher than those with benign lung disease and normal controls (p<0.01). The sensitivities of Hp, CEA, NSE and CYFRA21-1 were 43.5%, 40.9%, 23.3% and 41.5%, with specificities of 90.7%, 99.2%, 97.9% and 97.9%. Four tumor markers combined together could produce a positive detection rate of 85.0%, significantly higher than that of any single test. With squamous carcinomas, the positive detection rates with Hp and CYFRA21-1 were higher than that of other markers. In the adenocarcinoma case, the positive detection rate of CEA was higher than that of other markers. For small cell carcinomas, the positive detection rate of NSE was highest. The area under receiver operating characteristic curve ($AUC^{ROC}$) of Hp in squamous carcinoma (0.805) was higher than in adenocarcinoma (0.664) and small cell carcinoma (0.665). Conclusions: Hp can be used as a new serum tumor marker for lung cancer. Combination detection of Hp, CEA, NSE and CYFRA21-1 could significantly improve the sensitivity and specificity in diagnosis of lung cancer, and could be useful for pathological typing.

• The Korean Journal of Pain
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• v.29 no.1
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• pp.12-17
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• 2016

Background: The study aimed to determine if ultrasonography of masseter can be used to evaluate the outcome of transcutaneous electrical nerve stimulation (TENS) in subjects with temporomandibular disorders (TMDs) such as myositis and myofascial pain. Methods: Fifteen TMD subjects with myofascial pain/myositis who satisfied the RDC/McNeil criteria were included in the study. All the subjects were administered TENS therapy for a period of 6 days (30 minutes per session). The mouth opening (in millimeters) and severity of pain (visual analogue scale score) and ultrasonographic thickness of the masseter (in millimeters) in the region of trigger/tender areas was assessed in all the subjects both prior and post TENS therapy. A comparison of the pre-treatment and post-treatment values of the VAS score, mouth opening and masseter thickness was done with the help of a t-test. Results: There was a significant reduction in the thickness of masseter muscle (P = 0.028) and VAS scores (P < 0.001) post TENS therapy. There was also a significant improvement in the mouth opening (P = 0.011) post TENS therapy. Conclusions: In the present study, ultrasonography was found to be an effective measuring tool in the assessment of TENS therapy in subjects with myositis and myofascial pain.

• Journal of Advanced Navigation Technology
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• v.20 no.6
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• pp.528-538
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• 2016

In this paper, an extend kalman filter based relative navigation algorithm is proposed for Link-K based relative navigation. Link-K is a tactical data link system for joint operation capability upgrade of ROK forces. Link-K is inter-operable with Link-16 and transmit and received information of operations and target. In Link-K communication channel, PPLI message including transmitter position and TOA measurement can be used for relative navigation. Therefore Link-K based relative navigation system can be operated. In this paper, software based simulations were carried out for operational feasibility test and performance verification as error factors of proposed Link-K based relative navigation system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1460-1465
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• 2012

The semi-automatic gas metal arc welding equipment was developed and the weldability of zinc coated steel pipes was evaluated in terms of strength, porosity and welding parameters including shielding gas composition. The good bead appearance and the reduction of porosity in the welds could be possibly obtained by adding $O_2$ to Ar. The strength and joint efficiency of welds made by the semi-automatic welding equipment was about 1.8 times higher compared with welds manually made. The integrity of welds was confirmed by the water pressure test as well, Finally, it is expected that the weld productivity will be enhanced even unskilled welders can produce quality welds by operating the semi-automatic welding equipment.

• KIEAE Journal
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• v.8 no.3
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• pp.77-83
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• 2008

The effective mixture of structural laminated timber and other materials is expected to extend the potentials of building structures because of the potentials to realize high performance in structural safety. The classical joint types using drift pin and bolts are occurred local failures due to the small bearing area. In result, new joints using H shaped steel were suggested in this research. The objective of this study is to evaluate elasto-plastic behaviors by strengthening types of wood frames with new joints connecting structural laminated timber with H shaped steel. A total of five specimens of about one-second scale were tested. Specimens had columns with 1,050 height and $84mm{\times}100mm$ section, and a beams with 1,950mm length and $130mm{\times}100mm$ section. Also, the specimens were stiffened by brace, hwang-toh brick, and autoclaved lightweight concrete. The results of the test showed that the specimen stiffened with autoclaved lightweight concrete was characterized by fairly good strength and stiffness than those of the other specimens. Initial stiffness of H-2.0D-NS specimen with 2 times inserting length of beam height showed 1.33 times than that of H-1.5D-NS specimen. However, the strength of H-2.0D-NS specimen has not improved too much than H-1.5D-NS specimen.

• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.101-108
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• 2004

Asphalt overlay method is a general method to extend the of life old concrete pavements. However, reflection cracks are the typical problem of the AC overlay on distressed concrete pavement. Joint sealing, stress absorbtion layer have been used to prevent reflection cracks however partial success of to delay the timing of reflection cracking was recognized. Reflection crack problem can be eliminated by using rubblization method, which crush concrete pavement slab into piece of aggregate size that can be used base material. Previous research on rubblization method indicated that the size of rubblized PCC ranged 40-70mm at upper layer, and more than 100mm at lower layer. In this study, the adequate depth of rubblized PCC that ran prevent reflection cracking of AC overlay is estimated base on the simulation test of reflection cracking with 0, 10, 20cm rubblized PCC base.