• 한국환경과학회지
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• 제11권11호
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• pp.1183-1187
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• 2002

Existing retaining walls are usually made from only one cast form and any damage must be promptly repaired. However, when a part of a retaining wall is repaired, a gap can be created between the repaired and existing parts, along with an unpleasing visual effect. As such, the whole structure is often reconstructed, rather than repairing one part, resulting in construction waste and possible contamination of the environment. Accordingly, the current study proposes a construction method for a retaining wall that uses separate blocks to downsize of quantity of construction waste. In addition, by changing the color or modifying the block cover a more environmentally friendly retaining wall construction method is achieved.

• 한국유체기계학회 논문집
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• 제17권1호
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• pp.41-46
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• 2014

The thermal-flow characteristics of screw compressor were numerically investigated with various geometrical configurations of its coolant flow passage applied to the separate block for enhancing the heat transfer performance of it. The length ratio($L_s/D$=4.8, 5.6, 6.4) and thickness ratio(t/D=0.2, 0.4, 0.6) of the separate block in the flow passage of the water jacket were adopted to design parameters. Results showed that the pressure drop and heat transfer were increased as the length of separate block increases due to the flow separation and centrifugal force. The results were graphically depicted with various flow and geometrical conditions.

• 대한수학회논문집
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• 제13권3호
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• pp.635-642
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• 1998

When an integrated communication system is congested, we may reserve some spaces for non-realtime traffic by discarding a part of realtime traffic. That is sensible because realtime traffic is insensitive to a few losses. Several discarding schemes have been developed including Separate Queue (SQ). Under such schemes, the block loss distribution, i.e., the distribution of the number of losses within a given block which consists of successive data of a type, is important. We derive the block loss distribution of the SQ scheme and modifies the SQ scheme with a threshold.

• Structural Engineering and Mechanics
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• 제8권5호
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• pp.491-504
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• 1999

The initiation of toppling is explored for a uniform stack of blocks that rotates slowly about its mid-base. As the stack passes through its vertical position ($\theta$=0), it is in free-fall rotation, and a critical inclination angle ${\theta}_c$ is reached at which the toppling stack "fails" or begins to crack or separate. For tall stacks (high aspect ratios), two modes of failure are hypothesized, for which the dynamic failure analyses are shown to correlate with experimental results. These block failure modes are similar to those observed for tall, toppling masonry structures with weak binding material between their brick or stone blocks.

• Structural Engineering and Mechanics
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• 제90권5호
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• pp.505-515
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• 2024

In this study, obtaining theoretical stress-strain curves and determining the parameters defining the equivalent rectangular stress block were aimed for 3 and 4-layered rectangular Reinforced Concrete (RC) cross-sections subjected to flexure. For these aims, the analytical stress-strain model proposed by Hognestad was chosen for the concrete grades (20 MPa≤fck≤60 MPa) used in this study. The tensile strength of the concrete was neglected and the thickness of the concrete layers in the compression zone of the concrete cross-section was taken as equal. In addition, while concrete strength was kept constant within each layer, concrete strengths belonging to separate layers were increased from the neutral axis towards the outer face of the compression zone of the concrete cross-section. After the equivalent rectangular stress block parameters were determined by numerical iterations, variations of these parameters depending on concrete strength in layers and layer numbers were obtained. Finally, some analytical equations have been proposed to predict the equivalent stress block parameters for the 3 and 4-layered RC cross-sections and validities of these proposed equations were shown by different metrics in this study.

• 전자공학회논문지S
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• 제35S권2호
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• pp.89-96
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• 1998

Conventional block-based video coders induce annoying blocking artifacts in very low bitarte coding. We propose a delocking filter which is appropriate for real time operation in a conventional video decoder. The proposed algorithm uses on dimensional filtering across block boundaries horizontally and vertiaclly with two separate filtering modes. The mode decision is quite simple but is fully based on the characteristics of human visual system and video sequences. In flat regions, a strong smoothing filter is appliced; and in the other regions, a moew sophisticated smoothing filter, which is based on the frequency information around block boundaries, is used to reduce blocking artifacts without introuducing undesired blur. Eeven though the proposed deblocking filter is quite simple, simulation results show that it improves both subjective and objective image quality for various image features.

• 한국자동차공학회논문집
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• 제5권3호
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• pp.147-158
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• 1997

This paper presents the analysis technique and procedure of main engine components-cylinder block, cylinder liners, gasket and cylinder head-using the finite element method, which aims to assess mainly the potential of lower oil consumption in a view point of engine design and to decide subsequently the accuracy of engine design which was done. The F.E. model of an engine section consisting of one whole cylinder and two adjacent half cylinders is used, whereby the crankcase is cut off at the block bottom deck. By means of a 3-dimensional F.E. model-including cylinder block, liners, gasket, cylinder head, bolts and valve seat rings as separate parts a linear analysis of deformations and stresses was performed for three different loading conditions;assembly, thermal and gas loads. For the analysis of thermal boundary conditions also the temperature field had to be evaluated in a subsequent step.

• 신재생에너지
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• 제18권4호
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• pp.1-11
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• 2022

Landfill gas (LFG) generation characteristics in a construction waste landfill zone (block E) and mixed landfill zone (block A) were analyzed. During the period from October 2018 to April 2022, a total of 936×10³ and 1,001×10³ tons of waste were disposed in block E and block A, respectively. Out of this, 27.1% and 55.6% were biodegradable waste in block E and block A, respectively. The landfill masses of the two blocks were converted to be comparable. Then, the biodegradable waste and organic carbon were estimated by element analysis, biodegradable carbon by biochemical methane potential experiment (DC), and sulfate ion by acid decomposition. Results showed that biodegradable waste, organic carbon, biodegradable carbon, and sulfate ions in block A were 2.1, 1.6, 5.2, and 0.4 times greater than those in block E, respectively. The amount of LFG generated by block A was 4.8 times greater than that by block E. The average concentrations of methane (CH₄) were 60.8% and 60.9% in block E and block A, respectively, which were unrelated to the nature of disposed waste. The average concentrations of hydrogen sulfide (H₂S) were significantly high in block E (4,489 ppm) and block A (8,478 ppm). As the DC/SO₄^2- of block E and block A were 0.35 and 4.56, respectively, increase in DC/SO₄^2- caused increase in not only the total amount but also the concentration of H₂S generated.

• 한국수학교육학회지시리즈A:수학교육
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• 제46권2호
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• pp.227-237
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• 2007

This research analyzes students' response types in the creativity assessment by using pattern block, geoboard, and pantomino. 74 students from third grade to sixth grade participated in this research. 15 minutes were given to pattern block and geoboard questions. 74 students showed 393 answers in pattern block question and 590 answers in geoboard question. In pantomino, 20 minutes were given and 54 students showed 443 types of answers. The results are as follows: First, in the students' responses, tendency of using particular piece or figure, which presents conjoining in a piece selection and positioning, showed strongly. For example, usage of hexagon and trapezoid pieces were higer in pattern block and usage of L, P, and I pieces were higer in pentomino. Second, it is confirmed that creativity's subordinate factors, fluency, flexibility, and originality, are separate from each other. To illustrate, in pattern block, three students', who showed 11 types of responses in fluency, flexibility responses were each 5, 6, and 8 types. Specially, among those studenys, only one could achieve a point in originality. Third, students' response types categorized in this research could be used for a bae-data to mark grades on originality.

• 대한조선학회논문집
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• 제32권3호
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• pp.44-50
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• 1995

본 연구는 선체 블럭분할 작업을 지원하는 CAPP(computer aided process planning) 시스템 개발에 관한 것이며, 시스템 명은 BLOCK 이다. 시스템의 구성은 블럭분할선을 생성하는 전문가시스템과, 블럭분할선의 평가와 편집을 할 수 있는 분할 평가 및 수정 시스템으로 이루어져 있다. 전문가시스템의 추론 기법으로는 사례기반추론(case-based reasoning)기법을 이용하였다. 블럭분할선은 분할선 편집기에서 그래픽적으로 편집할 수 있고, 만족도 평가는 별도의 평가표 윈도우 상에서 할 수 있다. 전문가시스템은 웍스테이션 상에서 전문가시스템 개발 도구인 NEXPERT Object를 사용하여 개발하였다. 본 연구에서의 대상 선종은 VLCC이다.