• Journal of the Korean Wood Science and Technology
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• v.45 no.3
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• pp.243-249
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• 2017

This study was performed to find out the optimum adhesive conditions on manufacturing a cross-laminated timber (hereinafter CLT) with using domestic Korean Pine (Pinus koraiensis). The adhesive conditions including a applied amount of the glue and a Pressure are the one of the most important key factors on establishing CLT production process. The shear strength was examined with differing the adhesive conditions while using Phenol Resorcinol Formaldehyde Resin Adhesive (PRF resin). The optimum adhesive conditions was confirmed to be: glue spread of $250g/m^2$ and Pressure of 0.8 MPa respectively. The grain directions of glued specimens were also considered, perpendicularly bonded and parallelly bonded groups. Shear strength of the former group showed lower values than the latter group which is considered to be the effect of a rolling shear. Meanwhile the shear strength of both group satisfied the Korean Standard (KS F 3021) and the European Standard (EN 14080 and EN 16351). The results derived from this study can be used as the basic data for manufacturing the CLT with domestic Korean Pine. And additional researches for the other species including domestic Korean Larch and Pitch Pine is also now being performed.

• Korean Journal of Biological Psychiatry
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• v.14 no.4
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• pp.249-255
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• 2007

Objectives : The aim of this prospective study is to investigate predictors estimating relapse in Korean alcohol-dependent patients using variables like alcohol history, drinking craving, treatment motivation and insight. Methods : Alcohol dependent patients(N=48) who completed questionnaires about sociodemographic variables and drinking history, Timeline Follow-Back(TLFB), Obsessive-Compulsive Drinking Scale(OCSD), Alcohol Urge Questionnaire(AUQ), Pennsylvania Alcohol Craving Scale(PACS), University of Rhode Island Change Assessment(URICA), Hanil Alcohol Insight Scale(HAIS) were followed-up for 24weeks. Subjects who drank heavily(5 standard drinking or more/day) or were not followed up anymore were classified as the relapse group. We used logistic regression analysis with backward elimination of SPSS PC+11.5 to investigate relapse estimate predictors. Results : Average drinking amount per drinking day for last 1 year and HAIS score were predictors of relapse in alcohol-dependent patients. Conclusions : Our findings suggest that therapist should give more attention to alcohol-dependent patients who had more drinks per drinking day for last 1 year and had lower insight level.

• Journal of Biosystems Engineering
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• v.36 no.5
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• pp.326-333
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• 2011

The need for rapid on-site monitoring of hydroponic macronutrients has led to the use of ion-selective electrodes, because of their advantages over spectrophotometric methods, including simple methodology, direct measurement of analyte, sensitivity over a wide concentration range, and low cost. Stability and repeatability of response can be a concern when using multiple ion-selective electrodes to measure concentrations in a series of samples because accuracy might be limited by drifts in electrode potential. A computer-based measurement system could improve accuracy and precision because of both consistent control of sample preparation and easy calibration of sensors. Our goal was to investigate the applicability of a cobalt-based electrode used in conjunction with a laboratory-made automated test stand for quantitative determination of ${PO_4}^-$ in hydroponic solution. Six hydroponic solutions were prepared by diluting highly concentrated paprika hydroponicsolution to provide a concentration range of 1 to 300 ppm $PO_4$-P. A calibration curve relating electrode response to phosphate in paprika hydroponic solution titrated to pH 4 with 0.025M KHP was developed based on the Nikolskii-Eisenman equation with a coefficient of determination ($R^2$) of 0.94. The laboratory-made test stand consisting of three cobalt-based electrodes measured phosphate concentrations similar to those obtained with standard laboratory methods (a regression slope of 0.98 with $R^2$ = 0.80). However, the y intercept was relatively high, 30 ppm, probably due to the relatively large amount of variation present among multiple measurements of the same sample. Further studies on the high variation in EMFs obtained with cobalt electrodes during replicate measurements were required for P estimations comparable to those obtained with standard laboratory instruments.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3A
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• pp.163-172
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• 2011

The CFTA girder developed is a concrete filled steel tubular system with arched shape and external post-tensioning (PT) tendons which control the initial camber and the bending stress of the girder. In the present study the effects of the PT tendons on the dynamic behavior of the girder subjected to a moving vehicle load are numerically investigated. Various levels for the tendon quantity and the tendon forces are considered, using the existing FE model of the girder. The vehicle considered is a DB-24 truck and is modeled with two tracks-three axles. Equivalent-load pulse time histories are applied to each node to simulate the moving vehicle, depending on the time of arrival and the discretization. The vehicle speeds are varied from 40 km/hr to 100 km/hr with increment of 20 km/hr. The analysis results show that the tendon forces do not produce any influences on the dynamic responses of the girder. However the dymamic deflection of the girder increases when a smaller amount of tendons is used. The Dynamic Amplification Factors (DAF) are evaluated based on the static and dynamic responses. Much lower values of the DAF are obtained, even no tendons applied, than those provided by the design criteria of the AASHTO LRFD and the Korea Highway Standard Specification.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6311-6314
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• 2013

Background: While 5-port laparoendoscopic radical prostatectomy is standard practice, efforts have been focused in developing a single port surgery for cosmetic reasons. However, this is still in the pioneering stage considering the challenging nature of the surgical procedures. We have therefore focused on reduced port surgery, using only 2-ports. In this study, we compared 2-port laparoendoscopic radical prostatectomy (2-port RP) and conventional 5-port laparoscopic radical prostatectomy (LRP) for clinically localized prostate carcinoma and evaluated the potential advantages of each. Materials and Methods: From January 2010 to December 2010, all 23 patients with clinically localized prostate cancer underwent LRP. Starting November, 2010, when we introduced the reduced port approach, we performed this procedure for 22 consecutive patients diagnosed with early-stage prostate cancer (cT1c, cT2N0). The patients were matched 1:1 to 2-port RP or LRP for age, preoperative serum PSA level, clinical stage, biopsy and pathological Gleason grade, surgical margin status, pad-free rates and post-operative pain. Results: There was a significant difference in operative time between the 2-port RP and LRP groups ($286.5{\pm}63.3$ and $351.8{\pm}72.4$ min: p=0.0019, without any variation in blood loss (including urine) ($945.1{\pm}479.6$ vs $1271.1{\pm}871.8ml$: p=0.13). The Foley catheter indwelling period was shorter in the 2 port RP group, but without significance ($5.6{\pm}1.8$ vs $8.0{\pm}5.6$ days: p=0.057) and the total perioperative complication rates for 2 port RP and LRP were comparable at 4.5% and 8.7% (p=0.58). There was an improvement in pad-free rates up to 6 months follow-up (p=0.090), and significantly improvement at 1 year (p=0.040). PSA recurrence was 1 (4.5%) in 2-port RP and 2 (8.7%) in LRP. Continuous epidural anesthesia was used in most of LRP patients (95.7%) and in early 2-port RP patients (40.9%). In these patients, average total amount of Diclofenac sodium was 27.8mg/patient in 2-port RP and 50.0mg/patient in LRP. Conclusions: Thus the reduced port approach is as efficacious as LRP in terms of many outcome measures, with significant cosmetic advantages and reduction in post surgical pain. This method can be readily performed safely and therefore can be recommended as a standard laparoscopic surgery for prostate cancer in the future.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.226-231
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• 2010

We aimed at the monitoring medroxyprogesterone acetate (MPA) residue amount in meats and confirmed the safety of its residue in meats. Optimized condition for analytical and instrumental methods was obtained by method validation. The limit of detection (LOD) and limit of quantification (LOQ) were validated at 1.5 and 5.0 ug/kg, respectively. The calibration curve showed good linearity ($r^2$ = 0.9968) within the concentration range of 5.0~50.0 ug/kg. We selected progesterone-d9 for internal standard, The recoveries in fortified meat ranged from 67.5 to 109.56% at the 3 spiking levels. As the regulation of MPA analysis method used by LC-MS/MS on other products have established. We selected 3 species of farm stock products (cattle, pig, chicken) and purchased at the markets of seven major cities. The total 196 of meat including 46 of domestic beef, 43 of import beef, 60 of domestic pork, 12 of import pork and 35 of domestic chicken. No residue of synthetic growth hormones were detected in cattle, pig and chicken samples tested.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.147-161
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• 2017

Generally, significant amount of reinforcements are used in nuclear power plant structures and it may cause several potential problems during the construction. In particular, it is more difficult to pour concrete into structural member joint area than other areas because of the significant congestion of the joint area due to a lot of hooked bars, embedded materials, and other reinforcements. The purpose of this study is to solve these problems due to the reinforcement congestion by using the high-strength(ASTM A615 Gr.80) headed deformed bars of large-sized diameter(43 mm & 57 mm) in nuclear power plant structures as a alternative of standard hooked bars. In order to use headed deformed bars effectively, It is necessary to find the method how to relax limits on their use while maintaining or improving the anchorage capacity. Therefore, this study will analyze the results of tests planned to evaluate the influence of the restricted variables, such as bar size, yield strength, clear cover thickness.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.12
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• pp.2783-2790
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• 2010

In this paper, we first review LDPC codes in general and a belief propagation algorithm that works in logarithm domain. LDPC codes, which is chosen 802.11n for wireless local access network(WLAN) standard, require a large number of computation due to large size of coded block and iteration. Therefore, we presented three kinds of low computational algorithms for LDPC codes. First, sequential decoding with partial group is proposed. It has the same H/W complexity, and fewer number of iterations are required with the same performance in comparison with conventional decoder algorithm. Secondly, we have apply early stop algorithm. This method reduces number of unnecessary iterations. Third, early detection method for reducing the computational complexity is proposed. Using a confidence criterion, some bit nodes and check node edges are detected early on during decoding. Through the simulation, we knew that the iteration number are reduced by half using subset algorithm and early stop algorithm is reduced more than one iteration and computational complexity of early detected method is about 30% offs in case of check node update, 94% offs in case of check node update compared to conventional scheme. The LDPC decoder have been implemented in Xilinx System Generator and targeted to a Xilinx Virtx5-xc5vlx155t FPGA. When three algorithms are used, amount of device is about 45% off and the decoding speed is about two times faster than convectional scheme.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.8B
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• pp.668-676
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• 2012

In this paper, on the assumption that MPI collective communication function is converted into a group of point-to-point communication functions in the transaction level, an algorithm that optimizes broadcast, scatter and gather function among MPI collective communication is proposed. The MPI hardware engine that operates the proposed algorithm was designed, and it was named the OCC-MPE (Optimized Collective Communication Message Passing Engine). The OCC-MPE operates point-to-point communication by using the standard send mode. The transmission order is arranged according to the algorithm that proposes the most frequently used broadcast, scatter and gather functions among the collective communications, so the whole communication time is reduced. To measure the performance of the proposed algorithm, the OCC-MPE with the Bus Functional Model (BFM) based on SystemC was designed. After evaluating the performance through the BFM based on SystemC, the proposed OCC-MPE is designed by using VerilogHDL. As a result of synthesizing with the TSMC $0.18{\mu}m$, the gate count of each OCC-MPE is approximately 1978.95 with four processing nodes. That occupies approximately 4.15% in the whole system, which means it takes up a relatively small amount. Improved performance is expected with relatively small amounts of area increase if the OCC-MPE operated by the proposed algorithm is added to the MPSoC (Multi-Processor System on a Chip).

• Korean Journal of Environment and Ecology
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• v.17 no.3
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• pp.258-267
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• 2003

The purpose of this study is to present improvement devices of urban center's green function in the Public Open Space Attached Building(P.O.S.) in Incheon, Korea. Study sites were the P.O.S. of office building(10 place), transportation facility building(3 places), government office building(2 places) that were made up 1994∼2002 and analyzed establishment, using and planting status. And P.O.S.'s planting area structure of Osaka and Kawasaki in Japan that is operating P.O.S. system similar to Korea was compared with study sites of Incheon. P.O.S. of Incheon is not managing as valuable urban center's green and establishing to satisfy legal requirement. The strengthening devices of P.O.S. function are as follows. First, it is desirable that planting area rate of P.O.S. in order to develop small park in urban center is increasing by 40% that is children's park level. Second, it must be conferred about planting basis, tree selection and planting method etc. of P.O.S. with green and park development department at building authorization. Third, by the 'landscape planting standard of plottage' that is becoming planting standard of P.O.S is heightened and must increase quality and amount of green. Fourth, it is required mandatory establishing of sign so that citizens can search easily and utilize of P.O.S. Fifth, legal regulation should be decided to prevent that P.O.S. is used unlike purpose originally.