• Journal of Korean Society of Steel Construction
• /
• v.14 no.2
• /
• pp.319-327
• /
• 2002

Development of high-strength and light-weight structural steel as well as advancement in steel structure analysis enable construction of long span steel arch bridge. In an economic viewpoint, however, the design values of long span steel arch bridge needs to be optimized to reduce construction cost and achieve proper levels of structural safety. This study investigated the girder depth and the rise-span ratio for optimum design values, as well as the spectral analysis for protection against earthquake. The relationship between rise-span ratio and girder depth was derived based on the parametric studies of the basic span lengths of 60, 70, 80, 90, and 100m using a commercial Cis SAP2000. The equation relating the two variables was derived using linear regression.

• The Journal of Korean Society for Radiation Therapy
• /
• v.6 no.1
• /
• pp.21-30
• /
• 1994

To analyze the states of operation of radiotherapy facilities in the period from 1979 to 1992 and to get the base for efficient operation and maintenance of the radiotherapy facilities. Data on the records of annual number of patients operated by each facility; span of suspension of operation, the cost and span of repairing, and parts of oui-of-order in the period from 1979 to 1992 were analyzed. We made a comparative analysis of average annual number of patients, annual span of the suspension of operation, annual cost ratio of repair, span of repairing per break down, and total number of broken parts. We could get following annual number of patients(day), span of the suspension of span ($\%$)(day). annual cost ratio fo repair($\%$), span of repairing per break down(Min-Max, day), and number of broken parts from this analysis. 1. Cobalt unit (Picker C-9) : 10,389(43), 0.4(0.83) 0.07, 1hr-2, 3 2. Linac(Clinac 6/100) : 11,492(50), 4.0(9.57), 0.98, 1hr-30, 12 3. Linac(Clinac 18) : 9.115(44), 12.7(30.5), 3.54, 1hr-108. 41 4. Simulator(Picker Ther-X) : 2,017(9), 0.51(1.3), 0.24, 1hr-2, 7 5. RTP(Capentec Cap-plan) : 528(2), 0.4(0.93), - hrs, - The conclusion obtained from statistical analysis above are as follows. 1. The rate of operation of Cobalt unit($99.6\%$) was higher that of Linear Accelerators ($87.3\%$). The rates operation of Simulator and RTP computer were very close to that of Cobalt unit. 2. In order to raise up the working ratio of accelerator. it is desirable that we keep our engineer to learn a sufficient technical skill and the equipment agent to stock sufficient spare parts. 3. In order to maintain Linear Accelerator efficiently, it is desirable to have annually $2.3\%$ of the purchase price of equiment for repairing.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.17 no.9
• /
• pp.819-825
• /
• 2007

Vibration characteristics of an duel-cooling cylindrical fuel rod, which was proposed as a candidate design of fuel's cross section for the ultra-high burnup nuclear fuel, according to the cross-sectional dimensions and the number of supports or the span length were analytically studied. Finite element(FE) modeling for the annular cross sectional fuel was based on the methodology, that have been proven by the test verification, for the conventional PWR nuclear fuel rod. A commercial FEA code, ABAQUS, was used for the FE modeling and analysis. A planar beam element (B21) that uses a linear interpolation was used for the fuel rod and a linear spring element for the spring and dimple of the SG. Natural frequencies and mode shape were calculated according to the preliminary design candidates for the fuel's cross sectional dimension and the number of span. From the analysis results, the design scheme of the annular fuel compatible to the present PWR nuclear reactor core was discussed in terms of the number of supports and fuel's cross section.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2007.04a
• /
• pp.698-703
• /
• 2007

A simplified model which incorporates the moment-axial tension interaction of the double-span beams in a column-removed steel frame is presented in this paper. To this end, material and geometric nonlinear parametric finite element analyses were conducted for the double-span beams by changing the beam span to depth ratio and the beam size within some practical ranges. The beam span to depth ratio was shown to be the most influential factor governing the catenary action of the double-span beams. Based on the parametric analysis results, a simplified piecewise linear model which can reasonably describe the vertical, resisting force versus the beam chord rotation relationship was proposed. It was also shown that the proposed method can readily be used for the energy-based progressive collapse analysis of steel moment frames.

• Journal of the Korean Society of Industry Convergence
• /
• v.24 no.4_2
• /
• pp.501-507
• /
• 2021

In this study, In order to prevent the safety accidents caused by the sliding, to develop the non-slip grating, the stability judgment based on the span length of the grating and the gap of the bearing bar is performed. The structural analysis of Grating was carried out in accordance with the provisions set out in Grating's load-bearing test conditions. As the span length increases, the deflection increases and the stress and span length tend to be proportional to each other. It was shown that the larger the span, the linear increase in stress and exponential increase in deformation of grating. The maximum stress of grating was approximately 58.2 MPa, indicating a very stable safety rate of about 4.3 compared to the yield strength of the grating material. Based on these results, it will be able to be utilized as the basic data for determining the optimal dimensions of non-slip grading by performing optimal designs in the future.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2002.03a
• /
• pp.228-235
• /
• 2002

As the response spectrum method generally used in the earthquake resistant design is a linear method, the nonlinear behavior of a structure is to be reflected with a specific factor. Such factors are provided in the "Design Criteria for Roadwaybridges"as response modification factors and in the Eurocode 8, Part 2 as behavior factors. In this study a 5-span steel box bridge with single column piers is selected and the behavior factor is determined. The linear time history analyses are carried out with a simple linear model, where the nonlinear behavior of piers leading to the ductile failure mechanism is considered as predetermined characteristic curves.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.3
• /
• pp.619-626
• /
• 2013

The design of PN(Pseudo Noise) sequences with good cross-correlation properties is important for many research areas in communication systems. In this paper we propose new family of binary sequences $S^r=\{Tr_1^m\{[Tr_m^n(a{\alpha}^t+{\alpha}^{dt})]^r\}{\mid}a{\in}GF(2^n),\;0{\leq}t<2^n-1\}$ composed of Gold-like sequences and find the value of cross-correlation function when $d=2^{n-1}(3{\cdot}2^m-1)$, where n=2k, gcd(r, $2^m-1$)=1. Also we analyze the linear span of $S^r$ for some special r. Proposed sequences are extension of Gold-like sequences and GMW-sequences.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.13 no.4
• /
• pp.290-295
• /
• 2001

Subsets pipelines are exposed to several potential risks of damage due to corrosion, soil instability, anchor impact and other hazards. One of the main risk factors for the safety of a subsea pipeline is its free spanning. This paper examines the safety of subsea pipelines with free span under axial compressive load. The variation of allowable lengths of dynamic free span is examined for generalized boundary conditions. The free span is modelled as a beam with an elastic foundations and the boundary condition is replaced by linear and rotational springs at each end. A dynamic free span curve is obtained with a function of non-dimensional parameters and can be used usefully for the design of subsea pipelines with a free span. A case study is carried out to introduce the application method of the curve.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.7C
• /
• pp.534-539
• /
• 2008

For an odd prime p, n=4k, and $d=((p^{2k}+1)/2)^2$, Seo, Kim, No, and Shin derived the correlation distribution of p-ary m-sequence of period $p^n-1$ and its decimated sequences by d. In this paper, two new families of p-ary sequences with family size $p^{2k}$ and maximum correlation magnitude $[2]sqrt{p^n}-1$ are constructed. The linear complexity of new p-ary sequences in the families are derived in the some cases and the upper and lower bounds of their linear complexity for general cases are presented.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 1990.04a
• /
• pp.1-5
• /
• 1990

The object of this study introducts simple formula being based on energy principle to investigate span truss's non-linear, and considers the relation of member's length, height rate and slenderness ratio to rise prymid truss's economic structure ability through each example. This paper considered space truss's geometric non-linear behavior and material non-linear behavior, so acquired under result through as saying energy principle.