• Proceedings of the KSR Conference
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.375-378
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• 2007

The selection of the support system is an important design parameter in design and construction of the tunnel using the new Australian tunnel method. It is a common practice to select the support based on the rock mass grade, in which the rock mass is classified into five rock groups. The method is applicable if the characteristics of the rock mass are uniform in the direction of tunnel excavation. However, such case is seldom encountered in practice and not applicable when the properties vary along the longitudinal direction. This study performs comprehensive three dimensional finite difference analyses to investigate the ground deformation pattern for cases in which the rock mass properties change in the direction of the tunnel axis. The numerically calculated displacements at the tunnel crown show that the displacement is highly dependent on the stiffness contrast of the rock masses. The results strongly indicate the need to select the support type $0.5\sim1.0D$ before the rock mass boundary. The paper proposes a new guideline for selecting the support type based the results of the analyses.

• Proceedings of the KSR Conference
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.476-479
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• 2007

The selection of the support system is an important design parameter in design and construction of the tunnel using the new Australian tunnel method. It is a common practice to select the support based on the rock mass grade, in which the rock mass is classified into five rock groups. The method is applicable if the characteristics of the rock mass are uniform in the vertical direction. However, such case is seldom encountered in practice and not applicable when the properties vary along the vertical direction. This study performs comprehensive three dimensional finite difference analyses to investigate the ground deformation pattern for cases in which the rock mass properties change in the vertical direction of the tunnel axis. The numerically calculated displacements at the tunnel crown show that the displacement is highly dependent on the stiffness contrast of the rock masses. The results strongly indicate the need to select the support type $0.5{\sim}1.0D$(vertical direction) on the rock mass boundary. The paper proposes a new guideline for selecting the support type based the results of the analyses.

• Communications for Statistical Applications and Methods
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• 제24권4호
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• pp.383-396
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• 2017

The model in our approach assumes that computer responses are a realization of a Gaussian processes superimposed on a regression model called a Gaussian process regression model (GPRM). Selecting a subset of variables or building a good reduced model in classical regression is an important process to identify variables influential to responses and for further analysis such as prediction or classification. One reason to select some variables in the prediction aspect is to prevent the over-fitting or under-fitting to data. The same reasoning and approach can be applicable to GPRM. However, only a few works on the variable selection in GPRM were done. In this paper, we propose a new algorithm to build a good prediction model among some GPRMs. It is a post-work of the algorithm that includes the Welch method suggested by previous researchers. The proposed algorithms select some non-zero regression coefficients (${\beta}^{\prime}s$) using forward and backward methods along with the Lasso guided approach. During this process, the fixed were covariance parameters (${\theta}^{\prime}s$) that were pre-selected by the Welch algorithm. We illustrated the superiority of our proposed models over the Welch method and non-selection models using four test functions and one real data example. Future extensions are also discussed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• 제51권3호
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• pp.387-395
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• 2015

Starfish, a species of Echinoderm, is widely known as a predator on benthic invertebrate. A series of fishing experiments was carried out in the western coastal waters of Korea from September, 2011 to November, 2012, using the drum-shaped pots of different mesh sizes (17.1, 24.8, 35.3, 39.8, and 48.3 mm) to describe the composition of the catch species and the mesh selectivity of the pot for starfish. Some species including fish, crab, and starfish were caught in the experimental pots. The SELECT (Share Each Length's Catch Total) method was applied to describe the selectivity of the pot for starfish Asterina pectinifera. The master selection curve was estimated to be s(R) = exp(10.358R-4.086) / [1+exp(10.358R-4.086)], where R is the ratio of arm length to mesh size. The relative arm length of 50% retention was 0.395, and the selection range was 0.212. The results should be helpful to understand the relationship between the catch size of starfish and the mesh size of pot.

• Architectural research
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• 제18권2호
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• pp.75-82
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• 2016

To secure the anticorrosive performance of structures in the oceanic environment it is necessary to select appropriate finishing materials and thickness of cover. However, airborne chloride deposition varies depending on the collector used, and it is difficult to select appropriate finishing materials. For this reason, an eight-directional collector is proposed in this study through reviewing the differences between existing airborne chloride collectors and the new one. To analyze airborne chloride deposition according to the direction from which it flows and verify the performance of the collector proposed in this study, airborne chlorides were deposited on the collector for one year at five different locations in an oceanic environment. From the experiment, it was verified that in terms of direction, there were differences in airborne chloride deposition of up to more than 1.5 times. Based on these research findings, the anti-corrosive method applied can be different for each side of a building's structure, and this is believed to serve as an effective and systemic chloride resistance design.

• Journal of Korean Orthopaedic Sports Medicine
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• 제12권1호
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• pp.1-7
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• 2013

This article provides an overview of the current concepts regarding anterior cruciate ligament reconstruction, including anatomy, biomechanics, operative techniques and clinical results. Many techniques have been introduced for ACL reconstruction: single bundle reconstruction, remnant preserving augmentation, and double bundle reconstruction. Each technique has its strong and weak points, and it is not sure which technique is superior than others. It is considered to suggest that rather than to select the same method of surgery in all patients, select the method of reconstruction depending on the characteristics of the individual patient, the state of the residual ligaments and extent of the damage.

• Journal of the Korean Institute of Intelligent Systems
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• 제4권3호
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• pp.32-48
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• 1994

This paper proposes the compensation algorithm of conventional shift pattern using fuzzy reasoning in automatic transmission vehicles. Recently, automatic transimssion vehicles are continually increasing because of theire ease to drive. Also users require the high performance which includes the smooth shift quality and shift scheduling that matches driver;s intentions. So the shift scheduling has been inproved significantly through the application of electronic control. But, in spite of this development, vehicles using conventional shift pattern are sometimes in discord with driver's intention on roads. In this paper, the paper, the proposed compensation algorithm makes a automatic transmission vehicle be able to select an optimal gear shifting time and position using fuzzy reasoning and make a vehicle driver feel confortable even when the vehicle runs on roads which is extremely changed. Therefore, a vehicle driver can expect to reduce the nimber of unnecessary gear shifting and expect the fuel efficiency high. To show usefulness of the proposed method, some simulation are made to compared with conventional gear shifting. Paper prosposes the compensation mehtod of conventional shift pattern using fuzzy reasoning for the purpose that a vehicle can select an optimal gerar shifting time and position in automatic vehicle. Though the conventional shift pattern has no pliability, vehicle driver can feel comfortable and can reduce the number of unnecessary gear shifting using the proposed method on variable road condition. Therefore, it can be expected the fuel efficiency.

• The Transactions of The Korean Institute of Electrical Engineers
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• 제64권4호
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• pp.537-544
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• 2015

This paper provided two types of design method on moving core type LOA and one type of design method on moving coil type LOA, and compared and examined each of its characteristics. In order to conduct parametric design process, voltage equation was used to schematize Lmin/K and L/M map, and the schematized map was used to determine Lmin, K or L, M. In order to meet requirements such as thrust force and input voltage and to satisfy the target values of Lmin, K or L, M, the types and sizes of each type were designed using geometry design process. 2-FEA was conducted for each of the designed model. After examining thrust force based on the location of the mover, Type-1 showed radical change in thrust force as movers moved, and Type-2 and Type-3 showed constant appearance of thrust force. The total volume of the designed LOA model was compared to select the model with highest thrust force density. Also, the weight of the mover for each model was compared in order to select the model that was predicted to have highest mechanical responsiveness and stroke characteristics.

• Clean Technology
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• 제2권2호
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• pp.165-175
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• 1996

Cutting fluids in machining process are one of the parameters which have serious effects on the environment. A simple method to accomplish the environmentally clean process is to evaluate the effects of cutting fluids and select one which has the least environmental load. In this research, a process planning to select the best cutting fluid is suggested considering both machinability and environmental effects. The selection criteria and evaluation method named AHP are introduced. The planning process is illustrated with drilling characterized as a heavy-duty and low-speed process. Five standard fluids are compared with respect to five environmental attributes. Compounded cutting oils are superior to water-soluble oils in both machinability and environmental effects.

• International Journal of Highway Engineering
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• 제15권5호
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• pp.227-234
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• 2013

PURPOSES : In order to do an improving countermeasures for congestion on the highway with a limited budget, it is very important to select a habitual congestion section effectively. This study is develop CSI(Consitency Service Index) which contained the service for drivers on the highway to select a habitual congestion section. METHODS : By applying the concept of service for the users paying a fee, proposed CSI(Consistency Service Index) to determine habitual delay. CSI is mean that users using the highway road must be provided an environment which can driving more than 80kph, anytime, anywhere. RESULTS : The result applying developed method in this study included most of congestion sections selected by conventional method. but, in some section of existing non-congestion section were included by CSI. The annual average speed and CSI correlation analysis result was high correlation. This result proved that CSI was reflecting road traffic condition well. CONCLUSIONS : It was verified practicality from the delay section of gyeonggi-do area highway. we can judge whether or not to be a habitual congestion in the specific highway and do the traffic improving countermeasures accordingly.