• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.377-378
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• 2006

The knuckle crane mainly consists of six parts such as swing, main boom, outer boom, extension boom, hydraulic rotor and knuckle. And the hydraulic rotor is connected at the end of extension boom has rotor block, rotor body, rotor vane. In this study, we carried out kinematics analysis of the hydraulic rotor block curvature for a knuckle crane. Then, we showed the formula to establish the radius of a circumscribed circle to form the rotor block curvature. Third, we analyzed the stress at each point of the rotor block curvature according to the contact angle. From the result of this study, we designed the rotor block curvature with a proper contact angle for a knuckle crane to guarantee the stability of hydraulic rotor.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.12C
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• pp.1282-1287
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• 2002

In this Paper, we present the design of 10Mbps HomePNA(Home Phoneline Networking Alliance) PHY which is Home Network Technology using phone-line. It is connected with external interface through MII(Media Independent Interface) and AFE(Analog Front End) Interface. 10Mbps HomePNA PHY is composed with Management Block IEEE 802.3 CSMA/CD MAC(Media Access Control) Block Modulator block and Demodulator block. For their verification, we designed a prototype FPGA PCB board using XPC860T made in Motorola. We verified HomePNA frame data transmission using a driver program based Linux kernel. we verified rate negotiation by HomepNA 2.0 Link Layer Protocol.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.5
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• pp.356-361
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• 2014

Accurate block shape assessment is critical for ship manufacturing and a careful assessment of the shape of a fabricated block against the design shape is a core issue. However, in current fabrication practice, the shape of each block is evaluated manually using rigid body transformation. This manual evaluation process entirely depends on workers' experiences and knowledge and makes automation of block shape assessment difficult. In this paper we propose a computation method on the registration for shape assessment of a block during the fabrication process and for evaluation of its completion against the design shape. A conversion on matching method by adding DOF(degree of freedom) restriction is required to reach the goals. We test our method using a real block quality assessment data to demonstrate its applicability to real ship manufacturing process.

• Korean Journal of Computational Design and Engineering
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• v.15 no.1
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• pp.1-10
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• 2010

Recently, a shipyard is making every effort to efficiently manage equipments of resources such as a gantry crane, transporter, and so on. So far block lifting scheduling of a gantry crane has been manually performed by a manager of the shipyard, and thus it took much time to get scheduling results and moreover the quality of them was not optimal. To improve this, a block lifting scheduling system of the gantry crane using optimization techniques was developed in this study. First, a block lifting scheduling problem was mathematically formulated as a multi-objective optimization problem, considering the minimization of travel distance at an idle state and wire replacement during block lifting. Then, to solve the problem, a meta-heuristic optimization algorithm based on the genetic algorithm was proposed. To evaluate the efficiency and applicability of the developed system, it was applied to an actual block lifting scheduling problem of the shipyard. The result shows that blocks can be efficiently lifted by the gantry crane using the developed system, compared to manual scheduling by a manager.

• Journal of the Korean housing association
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• v.24 no.3
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• pp.9-18
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• 2013

This paper aims to investigate the design characteristics of a single housing block which is increasing in urban areas. For the analysis, all cases of single block housing in Daejeon metropolitan city were gathered into a database. Main concerns were on the location and the physical characteristics. The results of this study were as follows; 1) single block housing has been increasing both in the new developed areas and the existing urban areas 2) their location has shifted from residential districts to semi-residential and commercial districts. For this reason, the size and density has been increasing 3) the slab block with the hall type and the exterior corridor type were general in residential districts, diverse ones, however, including the point tower type were increasing with unusual circulation types such as central corridor, central core, double corridor, and mixed type in semi-residential and commercial districts 4) there were 5 types of access systems, and especially the street access and the piloti access were increasing, which were related with the high density.

• Computers and Concrete
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• v.24 no.5
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• pp.423-436
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• 2019

Design equations to evaluate the bursting force in a post-tensioned anchorage zone have been introduced in many design codes, and one equation in AASHTO LRFD is widely used. However, this equation may not determine the bursting force exactly because it was designed on the basis of two-dimensional numerical analyses without considering various design parameters such as the duct hole and shape of the bearing plate. To improve the design equation, modification of the AASHTO LRFD design equation was considered. The behavior of the anchorage zone was investigated using three-dimensional linear elastic finite element analysis with design parameters such as bearing plate size and diameter of sheath hole. Upon the suggestion of a modified design equation for evaluating the bursting force in an anchorage block with a rectangular anchorage plate (Kim and Kwak 2018), additional influences of design parameters that could affect the evaluation of bursting force were investigated. An improved equation was introduced for determining the bursting force in an anchorage block with a circular anchorage plate, using the same procedure introduced in the design equation for an anchorage block with a rectangular anchorage plate. The validity of the introduced design equation was confirmed by comparison with AASHTO LRFD.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.1450-1460
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• 2015

This study is to analyze various methods of block design elements applied in the recent apartment housing design competitions for Sejong city. It is expected to find the new design trend and good design characteristics of apartment building forms to use as the basic data of apartment housing design, because it is a case study on the ambitious design competition of the city that many major architectural firms in Korea entered and eager to propose new ideas. The results of this study are following : (1) The forms of slab block are classified into 8 types(the best applying one is ㄱ type). The forms of point block are classified into 9 types(the best applying ones are ㅁ, L and - type). (2) For the shapes of core, the forms of opposite core are classified into 6 types, the forms of parallel core are 3 types. (3) The forms of roof are classified into 4 types. The flat type is applied to 95 percent of the total cases. (4) The shapes of block mass are classified into 5 types(the best applying ones are general and void type), facade forms are 3 types(the best applying one is horizontal division type).

• Communications for Statistical Applications and Methods
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• v.6 no.1
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• pp.159-168
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• 1999

We introduce a new conditional signed-rank test for the tree alternatives comparing several treatments with a control in the randomized block design. We demonstrate its performance by comparing with 3 classes of signed-rank tests proposed by Park et al.(1991) in some general situations. In most cases the proposed procedure is simpler to compute and has better power than others.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.2
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• pp.724-737
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• 2020

Corrected Block TEA(or XXTEA) is a block cipher designed to correct security weakness in the original block TEA in 1998. In this paper, XXTEA cipher hardware which can encrypt or decrypt between 64-bit and 256-bit messages using 128-bit master key is implemented. Minimum message block size is 64-bit wide and maximal message block size is 256-bit wide. The designed XXTEA can encrypt and decrypt variable-length message blocks which are some arbitrary multiple of 32 bits in message block sizes. XXTEA core of this paper is described using Verilog-HDL and downloaded on Vertex4. The operation frequency is 177MHz. The maximum throughput for 64-bit message blocks is 174Mbps and that of 256-bit message blocks is 467Mbps. The cryptographic IP of this paper is applicable as security module of the mobile areas such as smart card, internet banking, e-commerce and IoT.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.205-209
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• 2000

This paper is concerned with development of the production-oriented structural design information system to predict the inaccuracy level of panel blocks and to consider the result at the structural design stage. Emphasis is placed on that the inaccuracy during production should likely be considered at the structural design stage to reduce the undesirable adjusting work and therefore to enhance the productivity. The primary goal of the present study is to consider the productivity and the efficient design at the same time for a high quality product of panel block. Usefulness of the developed information are illustrated through some application examples.