• Journal of Korean Society for Geospatial Information Science
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• v.4 no.2 s.8
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• pp.55-61
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• 1996

The objective of this paper is to show an optimal design model for branched water supply system which also can find the optimal location of pumping stations using linear programming. GIS is utilized in this model to better handle the data and the results front the optimization. The developed model considers hydraulic influences of some appurtenances such as supply tunnels and a filtration plant The model also considers tunnel construction cost which should be treated differently from pipe construction cost Different from other models presently available, the model guarantees a nonnegative pressure at every junction node in the system. The objective function includes annual operation cost (electricity rate) ill addition to initial construction cost, thus producing a more reasonable decision. The model selects the optimal diameter not in the form of continuous number but in the form of commercial discrete diameter (pipe size) using the pipe lengths as decision variables instead of pipe diameters. The model not only determines the optimal pumping head for each pumping station but also finds the optimal location and number of pumping stations. GIS is used to handle hydraulic and budgetary data automatically and to visualize the results for the of optimal design of the system. The model has been applied to an existing water supply system. 'The results show that the optimization model with the aid of GIS is helpful in the decision-nulling process for the design of more economical systems, and can be dot into practice successfully.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.140-145
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• 2018

This paper deals with the dynamical analysis of a two-point mooring vessel under surge excitations. The characteristics of nonlinear behaviors are investigated completely including bifurcation and limit cycle according to particular input parameter changes. The strong nonlinearity of the mooring system is mainly caused by linear and cubic terms of restoring force. The numerical simulation is performed based on the fourth order Runge-Kutta algorithm. The bifurcation diagram and several instability phenomena are observed clearly by varying amplitudes as well as frequencies of surge excitations. Stable periodic solutions, called the periodic windows, can be obtained in succession between chaotic clouds of dots in case of frequency ${\omega}=0.4rad/s$. In addition, the chaotic region is unexpectedly increased when external forcing amplitude exceeds 1.0 with the angular frequency of ${\omega}=0.7rad/s$. Compared to the cases for ${\omega}=0.4$, 0.7rad/s, the region of chaotic behavior becomes more fragile than in the case of ${\omega}=1.0rad/s$. Finally, various types of steady states including sub-harmonic motion, limit cycle, and symmetry breaking phenomenon are observed in the two-point mooring system at each parameter value.

• Magazine of the Korea Concrete Institute
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• v.5 no.4
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• pp.167-178
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• 1993

The objective of this paper is to look into the possibility of the detailed and practical optimum design of rt:inforced concrete beam using methods oi discrete mathematical programming. In this discrete optimum formulation, the design variables are the overall depth, width and effective depth of members, and area of longitudinal reinforcement. In addition, the details such as the amount of web reinforcement and cutoff points of longitudinal reinforcement are also considered as variables. Total cost has been used as the objective function. The constraints include the code requirments such as flexural strength, shear strength, ductility, serviceability, concrete cover. spacing, web reinforcement, and development length and cutoff points of longitudinal renforcement. An optimization algorithm is presented for effective optimum design of R.C. beam with discrete de sign variables. First, the continuous variable optimization can be achieved by Feasible Direction Method. Using the results obtained from the continuous variable optimization, a branch and bound method is used to obtained the discrete design values. The proposed algorithm is applied to test problem for reliability, and the results are compared with those of graphical method and rounded-up method. And a simply supported R.C. beam and a two-span continuous R.C. beam are presented as numerical examples for effectiveness and applicability. It is considered that the presented algorithm can be effectively applied to the discrete optimum design of R.C. beams.

• Journal of Korean Society of Forest Science
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• v.95 no.6
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• pp.729-734
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• 2006

This paper aimed to suggest decision-making method for forest management planning using integer programming. Thus, the study examined 85 stands consisting of Korean pine, Japanese larch and oak stands-all of which were at the most suitable time for tending, selection thinning, commercial thinning and final cutting-in the experimental forest of Kangwon National University. The forest management model comprised one objective function, maximizing harvest volume in each stand according to tree species and the kinds of practices, and seven constraints: frequency and stands of practices, minimum and maximum yields, even yields, maximum production, and decision-making varialbes. Besides, the entire period intended by the study was 10 years, divided into 5 management periods. In conclusion, the forest management planning model using integer programming proved that among 85 stands, forest practices were conducted over 68 stands (202.8 ha), producing the total harveted volume of $20,000m^3$, while the rest was reserved. This case study could help make decisions on whether and when the forest practices and harvests could be done in a specific condition.

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.41-46
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• 1983

Nine species of plant parasitic nematodes, Aphelenchoides besseyi, Aphelenchus avenae, Criconemoides informis, Helicotylenchus dihystera, Meloidogyne arenaria, Meloidogyne hapla, Pratylenchus minyus and Tylenchus sp. Were found in peanut field in Korea. Chemicals used were; Telon C-17, Mocap 10G and Carbofuran 3G for control peanut parasitic nematodes. All chemicals reduced nematode populations but varied in effectiveness. Telon C-17 was especially effective against Meloidogyne hapla, the principal species on peanut and resulted in significant yield increased than the control. Plant height, number of branches and dry weight of peanut were increased over the nontreated control by chemical soil treatments.

• Journal of KIISE:Databases
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• v.37 no.1
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• pp.12-21
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• 2010

Recently, "Service of information perspective" that is an important issue is that a company searches customers that interested in certain information and the company offers information to the customers. This service can gain high effects by low cost because of supporting selective information. In most recently, Reverse Skyline using Skyline Approximation(RSSA) is proposed to process services of information provider's perspective. RSSA has problem to defects about waste of processing time and memory. In this paper, Efficient Reverse Skyline(ERSL) Algorithm is proposed for Efficient processing the Skyline. ERSL is new Algorithm using Branch and Bound Skyline(BBS) reduces the waste of processing time and memory. When we execute the variety experimentation to valuation ERSL algorithm's capacity. It is proved the best efficient algorithm among the others because ERSL is flexibly kept the established capacity.

• Nuclear Engineering and Technology
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• v.11 no.1
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• pp.1-20
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• 1979

Neutron inelastic scattering studies on polycrystalline hydrates, NaBr-2$H_2O$ and BaCl$_2$-2$H_2O$ have been performed to observe librational modes. Assuming all observed peaks are from the $H_2O$ librational origin, the weighted frequency distribution functions are obtained by eliminating the contributions from the higher order processes. All of theoretical frequencies obtained using FG matrix method are dus to highly mixed modes, and therefore the modes identified as significant $H_2O$ librationat modes from their large potential energy distributions are assigned to the observed peaks. The H-bond interactions are estimated using a modified Lippincott Schroeder potential function, and the applicability of the potential function to the H-bond with highly bent or bifurcated configuration is examined on the basis of the shape of $H_2O$ librational potential energies. Some discussions are given on the usefulness of introducing O-H…Y bending terms in addition to the H…Y stretching in similar frequency calculation in order to obtain more information on the nature of H-bond. Also the purity and symmetry properties of the $H_2O$ librational modes are discussed using group theoretical analyses.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12B
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• pp.2335-2341
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• 1999

The $2\times32$ coupler consists of Mach-Zehnder interferometer and Y branch coupler. For the designs of this coupler, three dimensional rectangular core waveguide decomposed to two-dimensional structure by the effective index method. To optimize the waveguide structure, the confinement factor was investigated with two-dimensional finite difference Beam Propagation Method. The $2\times32$ coupler fabricated by simulation with height between Mach-Zehnder arms, H=$43.6\mu\textrm{m}$(path difference $0.668\mu\textrm{m}$) was showed best characteristics. In the results of dry etching of core layer, the etching rate of core layer was above 2600${\AA}$/min, the etching ratio of SiO2 to Al mask was 30:1 and the uniformity of etching was $\pm$5%. The maximum insertion loss and the uniformity of $2\times32$ coupler were below 19.2dB, 2dB respectively.

• Journal of Korean Society of Forest Science
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• v.37 no.1
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• pp.61-63
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• 1978

Both bark and wood sections obtained, by cutting with a razor blade, from living tissue of Cronartium ribicola cankers of Korean white pine (Pinus koraiensis) were transferred to a mixture of 2 parts of chloroform and 1 part of methanol, and the sections were stained using a modified lactophenol cotton blue. The formula for this staining is as follows: Lactic acid 20gm, phenol crystal 20gm, cotton blue 0.05gm, and 60% EtOH 100ml. The rust hyphae and haustoria were stained blue, and the wide hyphae with straight or curved haustoria could be distingwished from the pine tissue.

• Journal of Korean Society of Transportation
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• v.31 no.2
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• pp.80-89
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• 2013

The purpose of this research is to optimize the line planning of the intercity passenger railway. In this study, the line planning problem has been formulated into a mixed integer programming by minimizing both user costs (passenger's total travel time) and operator costs (operation, maintenance and vehicle costs) with multiple train types. As a solution algorithm, the branch-and-bound method is used to solve this problem. The change of travel demand, train speed and the number of schedules have been tested through sensitivity analysis. The optimal stop-schedules and frequency as well as system split with respect to each train type have been found in the case study of Kyoung-bu railway line in Korea. The model and results of this research are useful to make a decision for railway operation strategy, to analyze the efficiency of new railway systems and to evaluate the social costs of users and operators.