• The Korean Journal of Applied Statistics
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• v.31 no.5
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• pp.587-597
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• 2018

Procedures, such as sampling technique, survey method, and questionnaire preparation, are required in order to obtain sample data in accordance with the purpose of a survey. An important procedure is the decision of the sample size formula. The sample size formula is determined by setting the target error and total cost according to the sampling method. In this paper, we propose a sample size formula using population changes over time, estimation error of the previous time and response rate of past data when the target error and the expected response rate are given in the simple random sampling. In actual research, we use estimators that apply complex weights in addition to design-based weights. Therefore, we induce a sample size formula for estimators using design-based weights and nonresponse adjustment coefficients, that can be a formula that reflects differences in response rates when survey methods are changed over time. In addition, we use simulations to compare the proposed formula with the existing sample size formula.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.1
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• pp.82-88
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• 2017

In 2016, a handmade vehicle called to the VF-3 was designed and manufactured as a formula typed car. Prior to manufacturing and assembly, the impact attenuator was analyzed through ANSYS LS-DYNA, and the results were applied to the VF-3. The dynamical performance of the VF-3, such as the acceleration and circling simulations, was also assessed through MSC-ADAMS. The results were applied and compared after the Korean Society of Automotive Engineers (KSAE) competition. There was only a 0.8 s difference in the acceleration test. In order that the frame was not twisted by thermal deformation, Argon-TIG welding was used and a zig was designed. Another zig was designed to have the exact position for the hardpoints in the suspension system. Most of the parts were made with aluminum 7050 for reduced weight. The VF-3 won the third prize in the 2016 KSAE Student Handmade Vehicle competition.

• Journal of the Korean Home Economics Association
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• v.34 no.4
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• pp.249-263
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• 1996

According to the design method for constructing the G gori(the traditional Korean jacket)collar, there are differences in form after its completion. In the construction design of the midsection of the gusset as in that of the basic G gori, not only was the positioning of the two sides of the collar not smooth, but also, when the collar strip was attached, there would be an imbalance on one side or the other so that it was difficult to achieve symetry. Therefore in this project, by applying the pattern design of the gusset midsection to that of the collar midsection, not only did attaching the collar and the collar strip create a visual effect by equalizing the lengths of the tow sides, but the construction was also easy. This method of construction introduces the three-dimensional aspect of the human form in its conic, spherical and cylindrical aspects, so that, through schematizing the scientific character of Korea's clothing, its appropriateness is verified. As a matter of fact, since th-ere in no standardization of pattern whether for educational use or for mass-produced clothing, so that even the patterns used in computer-assisted design are executed according to the designer's personal skill, the reality is that after completion of construction the quality has not been uniform. For this schematization, inverse calculation of measurements pertaining to the calculation formula and of teaching materials has been referenced. In particular, the partial requlation of the calculation formula pertaining to the basic pattern construction, the method of making the collar midsection, and the construction method of the extreme and mean ratio adjustment can be adjusted for all measurements, thereby providing the establishment of a design criterion and the possibility of the standardization of construction methods. The production method for the pattern design is as follows: 1) The conic angle for the G gori's girth, length and neck width is fixed at 70 degrees. 2) The radius of the cone is B/2. 3) The calculation formula is B/4 + 1.5cm 4) The armhole formula is B/4, the same as in the basic method. 5) The width formula is B/10. 6) The ratio of the collar junction(width of collar + width of collar strip)to the gusset length is 5:8. 7) The length of the side seam is a length intersecting the armhole line and the conic radius (B/2), that is an arc that exceeds the length of the G gori's midsection; the component ratio of this length to the collar junction is accordingly 13:5. 8) The curve frame length of the back midsection is an arc exceeding B/4(the armhole line). 9) The ratio of the sleeve opening calculation formula to the armhole length is 8:5, forming an arc with the midsection length.

• International Journal of Control, Automation, and Systems
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• v.5 no.4
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• pp.471-478
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• 2007

In this paper, an optimal Wiener-Hopf decoupling controller formula is obtained which is expressed in terms of rational matrices, thereby readily allowing the use of state-space algorithms. To this end, the characterization formula for the class of all realizable decoupling controller is formulated in terms of rational functions. The class of all stabilizing and decoupling controllers is parametrized via the free diagonal matrices and the optimal decoupling controller is determined from these free matrices.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.125.1-125
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• 2001

This paper deals with the eigenvalue assignment technique for linear time-varying systems to achieve feedback stabilization. For this, we introduce the novel eigenvalue concepts. Then, we propose the Ackerman-like formula for linear time-varying systems. It is believed that this technique is the generalized version of the Ackerman formula forlinear time-invariant systems. The advantages of the proposed technique are that it does not require the transformation of the original system into the phase-variable form nor the computation of eigenvalues of the original system.

• Journal of applied mathematics & informatics
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• v.19 no.1_2
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• pp.105-125
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• 2005

Motivated by the field experimental designs in agriculture, the theory of block designs has been applied to several areas such as statistics, combinatorics, communication networks, distributed systems, cryptography, etc. An explicit formula and its fast computational algorithm for a class of symmetric balanced incomplete block designs are presented. Based on the formula and the careful investigation of the modulus multiplication table, the algorithm is developed. The computational costs of the algorithm is superior to those of the conventional ones.

• IE interfaces
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• v.6 no.2
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• pp.91-101
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• 1993

Developed in this paper is a standard time data for shirt sewing operations in the apparel-making industry. Since this data is made of formula developed for each unit operation and includes the formula for the machine time calculation, users could use it for obtaining the normal or standard time without any special efforts. In addition, this data handles the variations due to the design changes of a shirt through the parameters in the formula. compared with the MTM-1. The standard time data developed is shown to be easier and faster in determining the standard time with acceptable accuracy.

• Archives of Pharmacal Research
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• v.11 no.3
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• pp.185-196
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• 1988

The inflence of hydrophilic vehicles on percutaneous absorption rate of griseofulvin was studied using intact skin of full thickness of hairless rat. The in vitro absorption rates were used as the characteristics for deciding the optimum formula of ointment vehicles. The optimum formula of vehicle compositions for maximum absorption rate was obtained from the polynomial regression equation and the two graphical techniques, contour graph and partial derivative graph. It was composed of sodium lauryl sulfate (1.65 W /W%), white petrolatum (16.5 W /W%), propylene glycol (12.0 W /W%), and stearyl alcohol (19.6W /W%). The experimental value obtained from the optimum formula and the prediction value were 33.99 and 33.87 ${\mu}g/\sqrt{min}$, respectively. From these results, it was believed that optimum formula for semisolid dosage forms could be obtained from the application of the optimization technique used in this study.

• Journal of Environmental Science International
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• v.23 no.11
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• pp.1775-1790
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• 2014

The regional rainfall intensity formula for Gimhae in Gyeongsangnam-do province is developed in this study. The nine points of rainfall observations were selected. In order to demonstrate the accuracy and the versatility of the proposed rainfall intensity formula, three regions under the jurisdiction of the Meteorological Agency near Gimhae, namely Busan, Changwon, Miryang observatories were selected. The present formula can be effectively employed for various design of hydraulic structures in Gimhae area since it is divided into several refined regions.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.526-529
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• 2006

In this paper, flexure behavior of steel fiber reinforcement ultra high performance cementations composites (SFR-UHPCC) has been analyzed by equivalent stress block. Pulling-out tensile force of steel fiber with concrete matrix was induced. An appropriate flexure evaluation formula, i.e. semi-analytical formula, was established based on rectangular cross section beam for comparing with shear capacity and ultimate load of SFR-UHPCC beam. Finally, the semi-analytical formula has been simplified for the convenience of design work. Experimental results and theoretical shear strength are shown to compare with the formula proposed by this paper. The theory formula has a good prediction of failure type of SFR-UHPCC.