• Research in Mathematical Education
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• v.22 no.4
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• pp.261-282
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• 2019

The research related to testing pupils' achievement in the field of Measurement and Measure in initial teaching of geometry points to an insufficient adoption of the basic components of the length measurement concept among pupils. In order to discover the cause, we looked at the basic components on which the procedure of measuring length using a ruler is based, highlighted the possibilities of introducing the procedure in measuring length, and determined pupils' achievement during the procedure of measuring length using a ruler. The research sample consisted of 145 pupils, out of which 72 were the 2^nd grade pupils and 73 were the 4^th grade pupils. A descriptive method was applied in the research. The technique we used was testing, and for the statistical data processing we used a χ² test. The results of the research show that, when drawing a straight line of a given length using a ruler, there is no statistical difference in achievement between the 2^nd and 4^th grade pupils, nor in the pupils' knowledge regarding drawing a ruler independently, while drawing a straight line of a given length using a "broken" ruler 4^th grade pupils are statistically better. The results of the research indicate that pupils' achievement is better in doing standard tasks than in non-standard ones, given that the latter require conceptual knowledge. The components of the concept of length measurement using ruler have not been sufficiently developed yet, and these include: zero-point, partitioning a measured object in a series of consecutive measurement units and their iteration. We shed more light on the critical stage in the procedure of length measurement - the transition from non-standard to standard units and the formation of the length measurement scale. For further research, we propose to look at the formation of the concept of length measurement using the ruler through all its components and their inclusion in the mathematics curriculum, as well as examining the correlation of pupils' achievement in the procedure of measuring length with their achievement in measuring area (and volume).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.531-542
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• 2017

The structural safety of small craft, such as steel ships and FRP ships, can be estimated using the measurement test of the hull plate thickness or the longitudinal bending strength test. A polyethylene boat is made using inexpensive HDPE and can be mass produced. The structural safety of a polyethylene boat cannot be guaranteed because a polyethylene boat hull is notspecified in the KR technical rules. The inspection procedure of sailing yachts and pleasure boats and drop test method of ISO standard 12215-5 propose the structural strength required for small crafts as the drop test height. Therefore, in this study, the drop test of a polyethylene boat hull was carried out based on the inspection procedure of a sailing yacht and pleasure boat and the drop test method of ISO standard 12215-5. The drop load was acquired by the drop acceleration ofa boat hull. Structural analysis and safety of a polyethylene boat were performed by the drop load and allowable stress criteria. The calculation results of the hull plate thickness by structural design specification of ISO standard 12215-5 showed that polyethylene boat hull was more than two times thicker than a steel ship hull and the boat hull determined by the inspection procedure of sailing yacht and pleasure boat and drop test method of ISO standard 12215-5 was more than 1.2 times thicker than the boat hull determined by structural design specification of ISO standard 12215-5. Therefore, inspection procedure of sailing yachts and pleasure boats and drop test method of ISO standard 12215-5 was much more conservative than the structural design specification of ISO standard 12215-5 and could be used as the structural design method of a polyethylene boat.

• Journal of the Korean Society of Safety
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• v.33 no.5
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• pp.21-27
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• 2018

The purpose of this study is to develop a SOP (Standard Operating Procedure) for a distribution board that can monitor the leakage current of a load distribution line in real time. The developed distribution board was fabricated by applying IEC 61439-1. It consists of the distribution board and an alarm device. The work process for making the distribution board was compliant with the KEMC (Korea Electrical Manufacturers Cooperative) regulations. And the AC distribution board range is 1,000 V. In addition, the voltage in DC is less than 1500 V. The distribution board receives a 3-phases and 4-wires power supply system and can supply power to the load of a maximum of 32 single or three phase distribution circuits. Also, leakage current measured on the power distribution board was used by sensors installed. The SOP of the developed distribution board consists of the installation standards for the short circuit alarm device and sensor, the surge protection device, switches and indication lamps, and other devices. The operation procedure was prepared so that each manufacturing step of the distribution board must be confirmed by the persons in charge of preparation, production, quality control and approval before moving forward to the next step.

• Journal of Applied Reliability
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• v.17 no.1
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• pp.28-37
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• 2017

Purpose: This paper proposes a procedure that may infer and identify interaction failures in a module. Methods: In design FMEA, we defined an interaction model between components and proposed a method for selecting a single component by using the standard specification classification table and four methods for choosing the related components. We also introduced the function tree for function and requirement characteristic analysis and proposed utilization of standard stress lists and 1st and 2nd stress analysis tables to determine the effect the stress analysis has on interactions. Finally, the interaction mechanism diagram was proposed and used to infer the failure mechanism. Process FMEA also established procedures in a similar way. Results: We established a procedure for predicting the failure mode due to interaction between components based on Company A's multi-step FMEA procedure. Conclusion: By applying the proposed interaction FMEA procedure to the development model, we were able to confirm the effect of the new derivation on the failure mode of interaction, which was not predicted by the existing FMEA.

• Korean Journal of Computational Design and Engineering
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• v.15 no.1
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• pp.60-69
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• 2010

Outfitting systems in marine vessels have many kinds of standard parts. Ship CAD system should support the designers with an efficient tool for the modeling of outfitting parts such as pipes and valves. We develop a practical procedure for a part master model that combines ship CAD systems with the industrial standard. Part master or catalogue database of standard equipments is included in the database of ship CAD. The part master makes the associations of three dimensional modeling with the industrial standard. Moreover, it reflects the automatic modeling to maintain attributes that are disclosed in the entity of each part master in order to reduce the modeling time. Entity and attributes of pipe and valves are chosen from JIS(Japanese Industrial Standards) in order to explain the proposed procedure. Suggested procedure explains that three dimensional model of equipment is generated by parsing the pre-defined attributes after the entities of part masters is stored in database.

• Journal of the Korean Data and Information Science Society
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• v.17 no.2
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• pp.467-474
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• 2006

In this paper we present a weighted support vector machine(SVM) and a weighted least squares support vector machine(LS-SVM) for the prediction in the heteroscedastic regression model. By adding weights to standard SVM and LS-SVM the better fitting ability can be achieved when errors are heteroscedastic. In the numerical studies, we illustrate the prediction performance of the proposed procedure by comparing with the procedure which combines standard SVM and LS-SVM and wild bootstrap for the prediction.

• Proceedings of the KSPS conference
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• 2005.04a
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• pp.37-40
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• 2005

Recently due to the rapid development of speech synthesis based on the corpora, the performance of TTS systems, which convert text into speech through synthesis, has enhanced, and they are applied in various fields. However, the procedure for objective assessment of the performance of systems is not well established in Korea. The establishment of the procedure for objective assessment of the performance of systems is essential for the assessment of development systems for the developers and as the standard for choosing the suitable systems for the users. In this paper we will report on the results of the basic research for the establishment of the systematic standard for the procedure of objective assessment of the performance of Korean TTS systems with reference to the various attempts for this project in Korea and other countries.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.440-442
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• 2001

Calibration procedure of high-current measuring system has been promoted to ensure the traceability of national of international standard with the similar method of high-voltage measuring system. This paper introduces general procedure to establish the traceability and type & performance tests for current-voltage transformer, transmission system, recorder and evaluation procedure as the result of intercomparison tests performed 7 laboratories of Europe, and introduces briefly the test method of itemized list from type & performance tests. So we would apply the standard as the criteria that can be enforced temporarily in korea.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.6
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• pp.199-208
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• 1994

This paper proposes a delay fault test technique for ICs and PCBs with the boundary-scan architectures supporting ANSI/IEEE Std 1149.1-1990. The hybrid delay fault model, which comprises both of gate delay faults and path delay faults, is selected. We developed a procedure for testing delay faults in the circuits with typical boundary scan cells supporting the standard. Analyzing it,we concluded that it is impractical because the test clock must be 2.5 times faster than the system clock with the cell architect-ures following up the state transition of the TAP controller and test instruction set. We modified the boundary-scan cell and developed test instructions and the test procedure. The modified cell and the procedure need test clock two times slower than the system clock and support the ANSI/IEEE standard perfectly. A 4-bit ALU is selected for the circuits under test. and delay tests are simulated by the SILOS simulator. The simulation results ascertain the accurate operation and effectiveeness of the modified mechanism.

• Structural Engineering and Mechanics
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• v.69 no.1
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• pp.95-104
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• 2019

The Standard ASCE 61-14 proposes the Substitute Structure Method (SSM) as a Nonlinear Static Procedure (NSP) to estimate nonlinear displacement demands at the center of mass of piers or wharves under seismic actions. To account for bidirectional earthquake excitation according to the Standard, results from independent pushover analyses in each orthogonal direction should be combined using either a 100/30 directional approach or a procedure referred to as the Dynamic Magnification Factor, DMF. The main purpose of this paper is to present an evaluation of these NSPs in relation to four wharf model structures on soil conditions ranging from soft to medium dense clay. Results from nonlinear static analyses were compared against benchmark values of relevant Engineering Design Parameters, EDPs. The latter are defined as the geometric mean demands that are obtained from nonlinear dynamic analyses using a set of 30 two-component ground motion records. It was found that SSM provides close estimates of the benchmark displacement demands at the center of mass of the wharf structures. Furthermore, for the most critical pile connection at a landside corner of the wharf the 100/30 and DMF approaches produced displacement, curvature, and force demands that were reasonably comparable to corresponding benchmark values.