수축저감제와 혼화재를 병용한 콘크리트의 공학적 특성

金光華,김종,한민철,정평유,한천구 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

The objective of this paper is to investigate the physical and mechanical properties of concrete incorporating shrinkage reducing admixture(SRA) and mineral admixture(MA) such as fly ash and blast furnace slag powder. According to results, for fresh concrete properties, increase of SRA content leaded to reduce the fluidity and air content sharply. For setting time, use of SRA caused concrete to accelerate setting time, and compared with plain concrete it retarded by incorporating MA. Compressive strength decreased with an increase in SRA content, and when incorporating MA, compared with plain concrete, it shows lower compressive strength in early age but similar or increase by the elapse of age due to the pozzolanic and latent hydration reaction. For drying shrinkage, concrete shows decline tendency with an increase in SRA content due to the relaxation effect at the capillary tension in concrete by SRA. In the scope of this paper, it is found that the use of SRA with 1.0% has optimum effects on the various properties of concrete, and the combinations of SRA and fly ash will ensure the stability for drying shrinkage.

수축저감제 혼입률 변화에 따른 콘크리트의 공학적 특성에 관한 연구

한민철,金光華,정규문,정평유,윤성노,한천구 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2

In this paper, tests are carried out using concrete incorporating shrinkage reducing agent(SR) in order to investigate the engineering properties of concrete. The contents of SR and W/C are varied. According to test results, as for fresh concrete, as SR content increases, slump and air content shows decline tendency, and setting time is accelerated with increase of SR content and decrease of W/C. As for compressive strength, as SR contents increases compressive strength shows to be decreased. As for the effect of SR on drying shrinkage, it shows to be reduced with increase of SR content. This is due to the reduced surface tensile strength of water and tensile strength of capillary pore in concrete.

The Research of 3 D Point Cloud Registration Method Based On Regular Hexahedron Color Targets

Yu Guang,Shi Yunbo,Yu Boyang 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.4

Coded structured light measurement is the important method of modern non-contact optical measurement, restricted by the camera field of view, the surfaces to be measured can complete a single perspective measurement, this is the 3 d point cloud registration, point cloud registration can reflect three-dimensional topography on the surface of the object, and it has reached the requirement of comprehensiveness.This paper has built coded structured light 3 d measurement system, to explore 3 d point cloud registration method based on regular hexahedron color targets with high accuracy, fast registration, which can be applied to industrial components comprehensive measuring characteristics.

Study on Multi Objective Optimization Method and It Application in Aviation and Deceleration Device

Yu Guang-bin,Song Ye,Duan Yuan-wang,Zhao Xing-fu,Qu Zhigang,Sun Yong-guo 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.5

An Empirical Study of the Renminbi Equilibrium Exchange Rate

Yu Seung Hun,Yu Guang Dong 한국무역연구원 2013 貿易 硏究 Vol.9 No.2

In order to analyze the massive trade imbalance between China and America, we discuss the degree of RMB's misalignment in a tractable framework by estimating the long run equilibrium real effective exchange rate of the currency during 1980-2009 in this paper. Based on estimation of behavioral equilibrium exchange rate (BEER) and using Johansen co-integration technique, we conclude that RMB fluctuates around its long-run equilibrium exchange rate within a range of positive 3% and minus 4% bands. This implies that the currency has not been significantly undervalued or overvalued. According to the four control variables (terms of trade, GDP per capita, foreign exchange reserve and money supply), we deem that increase of foreign exchange reserve and per capita output, decrease of money supply will lead to the appreciation of RMB real effective exchange rate. Implications of the empirical findings of this study indicates China's exchange rate policy may have played an insignificant role in its trade surpluses.

Development of gradient composite shielding material for shielding neutrons and gamma ray

Guang Hu,Guang Shi,Huasi Hu,Quanzhan Yang,Bo Yu,Weiqiang Sun 한국원자력학회 2020 Nuclear Engineering and Technology Vol.52 No.10

In this study, a gradient material for shielding neutrons and gamma rays was developed, which consists of epoxy resin, boron carbide (B4C), lead (Pb) and a little graphene oxide. It aims light weight and compact, which will be applied on the transportable nuclear reactor. The material is made up of sixteen layers, and the thickness and components of each layer were designed by genetic algorithm (GA) combined with Monte Carlo N Particle Transport (MCNP). In the experiment, the viscosities of the epoxy at different temperatures were tested, and the settlement regularity of Pb particles and B4C particles in the epoxy was simulated by matlab software. The material was manufactured at 25 °C, the Pb C and O elements of which were also tested, and the result was compared with the outcome of the simulation. Finally, the material's shielding performance was simulated by MCNP and compared with the uniformity material's. The result shows that the shielding performance of gradient material is more effective than that of the uniformity material, and the difference is most noticeable when the materials are 30 cm thick.

A Kind of Encryption Method of QR Code based on ECA State Ring

Yu Guang,Shi Yunbo,Che Chang 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.9

In view of the simple keys, time-consuming in encryption and decryption process and the loss of original function characteristics in encrypted image QR two-dimensional code, we adobe a kind of encryption method of QR code based on ECA state ring. In this method, the simple structure, highly parallel of elementary cellular automaton is being used. Operating each pixel point on the quick response code except which can express QR code function information. The simulation results show that the method is faster than two kinds of typical QR code encryption method, and the encrypted image can preserve the original QR code function information, while the safety coefficient is very similar.

Design and Application of High Energy Collision Flexible Buffer

Yu Guang-bin,Guan Yan-qi,Yang Xiao-hui,Bu Jing-yuan 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.9

Introduces a suitable for steep inclined shaft sports car flexible buffer design method, given the high energy collisions flexible buffer mathematical model and simulation test is conducted, designed a high energy collision flexible buffer, to solve the problem of conventional buffer buffer distance is too long, the vehicle off road and so on, through the friction between the wire rope and the buffer to absorb the energy of the sports car, and realize the effective interception of the vehicle, ensure that the vehicle has a short distance to stop the car, and ensure the safe and reliable operation of the anti-car system. To ensure the safety of coal mine rail transport is of great significance.

Neutrophil-to-lymphocyte ratio independently predicts advanced pathological staging and poorer survival outcomes in testicular cancer

Yu Guang Tan,Joshua Sia,Hong Hong Huang,Weber Kam On Lau 대한비뇨의학회 2019 Investigative and Clinical Urology Vol.60 No.3

Purpose: An elevated neutrophil-to-lymphocyte ratio (NLR) has been associated with adverse outcomes in various malignancies. However, its role in prognosticating testicular cancer (TC) has not been validated. We aim to study the relationship between NLR and TC. Materials and Methods: We retrospectively reviewed 160 patients with histological proven TC from January 2005 to June 2016. Youden's index was used to analyse NLR and a cut-off point of 3.0 was obtained, with statistical receiver operating characteristics of 0.755. Chi-square test, Kaplan-Meier (log rank test) and logistics regression models were used to predict NLR association with survival outcomes. Results: Median age was 34 years old (range, 17–68 years old). There were 102 pure seminomas and 58 non-seminomatous germ cell tumours. Median follow-up period was 8 years (range, 2.5–17 years). NLR ≥3.0 was independently associated with lymph node involvement (p=0.031; odds ratio [OR], 2.91; 95% confidence interval [CI], 1.67–5.83; p=0.038; OR, 4.12; 95% CI, 1.26–6.51) and metastatic disease (p=0.041; OR, 2.48; 95% CI, 1.22–3.98; p=0.043; OR, 2.21; 95% CI, 1.17–3.65) in both seminomatous and non-seminomatous germ cell tumours, translating to a more advanced disease. Moreover, NLR ≥3.0 also predicts poorer cancer specific survival in these patients. Conclusions: NLR can be an inexpensive haematological marker in predicting advanced TC staging and poorer survival outcome. NLR complements the traditional cancer staging by identifying a group of high risk patients who may benefit from multimodal treatment and closer surveillance to achieve long term survival.

Reestimation of The Renminbi

Guang-Dong Yu,Seung-Hun Yu 한국무역연구원 2014 貿易 硏究 Vol.10 No.3

In this paper, we analyze mainly the well-known relationship between deviation from absolute purchasing power parity and real per capita income by using panel regression models, and verify Balassa-Samuelson effects. We determine how much of the degree of misalignment of the renminbi (RMB) stands relative to the equilibrium real exchange rate using these methods. Although undervaluation or overvaluation of the RMB exists, most of the misalignments from the equilibrium exchange rate keep within two standard error bands. The Balassa-Samuelson effects are at work. Even considering the serial correlation and control variables (demographic variables, current account, M2/GDP, capital openness, corruption index, an interaction term), similar results can be obtained.