• Ocean Systems Engineering
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• v.9 no.1
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• pp.97-109
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• 2019

Accurate calculation of the mean drift forces and moments is necessary when studying the higher order excitations on the floater in waves. When taking the time average of the second order forces and moments, the second order potential and motion diminish with only the first order terms remained. However, in the results of the first order forces or motions, the irregular frequency effects are often observed in higher frequencies, which will affect the accuracy of the calculation of the second order forces and moments. Therefore, we need to pay close attention to the irregular frequency effects in the mean drift forces. This paper will discuss about the irregular frequency effects in the calculations of the mean drift forces and validate our in-house program MDL Multi DYN using some examples which are known to have irregular frequency effects. Finally, we prove that it is necessary to remove the effects and demonstrate that the effectiveness of the formula and methods adopted in the development of our program.

• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.396-405
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• 2011

The purpose of this study was to reduce safety accidents among food employees in contracted foodservice management companies, and to help provide high-quality foodservice and assistance. For this, a survey on the different opinions of workplace safety and education by employment type and employee perceptions of environment and safety at foodservice operations was carried out. The analysis showed that among the workers many women were irregular employees. For average age, between 40 and 49 was the most frequent, and for work duration, under one year was highest. Both regular employees and irregular employees deemed "enough staff" as the most major factor for good foodservice. The regular employees and irregular employees thought "high indoor temperatures and poor ventilation in the kitchen area" and "bad work cooperation between employees" as the main problems of foodservice operations, respectively. For satisfaction with the efficiency of foodservice production system, irregular employees had higher satisfaction than regular employees. Both regular employees and irregular employees thought "the number of foodservice employees" as the foremost improvement for safety-accident prevention and work-stress improvements. Regular employees, more than irregular employees, thought improvements in foodservice production systems would have a large affect on safety-accident prevention and work-stress improvements of food workers. Both regular employees and irregular employees thought "foodservice employees' safety consciousness" was an important part of safety-accident prevention. Likewise, they responded that "lectures by the person in charge of safety education" was a good methods of safety education, and "once a month" was the best period for safety education. For the difference in perceptions of environment and safety in foodservice systems, regular employees had a higher perception of safety than irregular employees.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.783-791
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• 2006

The consciousness and eating habits of the housekeeper directly influence the stress level and health quality of the household occupants. In Korea, most housewives are in charge of dietary life. Accordingly, their attitudinal clusters toward dietary (eating) life were researched in relation to their stress and health. The research results showed that irregular eating habits cause stress. Therefore, it is necessary for housewives to have a regular eating habit. The results were as follows. The house wives' attitudes toward dietary life were categorized into 5 clusters: regular and speedy overeating, regular and frequent eating, regular and light eating, irregular and light eating, irregular and speedy overeating. The cluster of regular and frequent snacks was 24.3%. The cluster of irregular and speedy overeating caused the most stress. Especially the house wives' group belonging to the cluster of irregular and speedy overeating were under social and emotional stress, while the cluster of regular and light eating and the cluster of irregular and light eating were under concentration stress. The cluster of regular and frequent snacks and the cluster of irregular and light eating had negative effect on their health, while the cluster of regular and speedy overeating had negative effect on their family's health by their social stress.

• Journal of the Korean Data and Information Science Society
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• v.17 no.1
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• pp.141-147
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• 2006

BOK-X12-ARIMA has been developed by the Bank of Korea in order to accomodate special features such as lunar effect, labor day and election effect which are intrinsic in Korean seasonal time series. Irregular component resulting from BOK-X12-ARIMA is usually treated as white noise time series. If this shows dependency structure, it may be advisable to incorporate dependency in irregular component into prediction. This article illustrates how to refine point forecast using dependency structure in irregular component.

• Korea Journal of Hospital Management
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• v.13 no.4
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• pp.119-145
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• 2008

The objectives of this study were to inspect how the law effected on hospital employment system and which policy and strategy are needed to cope with the present situation as the law regarding irregular workers law has enacted for a year. To grasp the changes of employment style in hospital, 56 hospitals among 311 general hospitals were questioned in this study. And employment policy and strategy were developed by referencing examples of developed nations and other industries. The survey showed that the wage and welfare level of irregular workers in hospitals was improved compared to that in the other industries. But there were still much discrimination between regular and irregular workers. The policy direction of government is, first of all, to follow the principle of equal treatment to equal value of labour. The first feasible policy is to enforce social security. The second one is an employment promotion policy which reduces or exempts hospitals employing irregular workers from tax and insurance fee. The third one is to extend employment contract period to 3 years. and finally there are policies to permit more dispatched jobs and to expand the social insurance coverage. The strategies to solve the problem of irregular workers are as follows; 1) performance wage system, 2) guaranteeing employment by unlimited contract, 3) creating new category of workers, 4) the wage system of management by object, 5) the method of job classification. This study has a meaning in the point that it was studied on hospital which is special industrial part and analyzed the changes after enacting irregular workers law and presented management strategy for countermeaure program. In this study, it was expected to contribute to decisions-making in hospital management, especially when using human resources.

• Earthquakes and Structures
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• v.9 no.2
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• pp.353-373
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• 2015

In this paper, the effects of different types of irregularity along the height on the seismic responses of moment resisting frames are investigated using nonlinear dynamic analysis. Furthermore, the applicability of consecutive modal pushover (CMP) procedure for computing the seismic demands of vertically irregular frames is studied and the advantages and limitations of the procedure are elaborated. For this purpose, a special moment resisting steel frame of 10-storey height was selected as reference regular frame for which the effect of higher modes is important. Forty vertically irregular frames with stiffness, strength, combined-stiffness-and-strength and mass irregularities are created by applying two modification factors (MF=2 and 4) in four different locations along the height of the reference frame. Seismic demands of irregular frames are computed by using the nonlinear response history analysis (NL-RHA) and CMP procedure. Modal pushover analysis (MPA) method is also carried out for the sake of comparison. The effect of different types of irregularity along the height on the seismic demands of vertically irregular frames is investigated by studying the results obtained from the NL-RHA. To demonstrate the accuracy of the enhanced pushover analysis methods, the results derived from the CMP and MPA are compared with those obtained by benchmark solution, i.e., NL-RHA. The results show that the CMP and MPA methods can accurately compute the seismic demands of vertically irregular buildings. The methods may be, however, less accurate especially in estimating plastic hinge rotations for weak or weak-and-soft top and middle storeys of vertically irregular frames.

• Journal of applied mathematics & informatics
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• v.17 no.1_2_3
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• pp.297-305
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• 2005

In this paper, we study irregular 3D-Arrays with pyramid shapes. Some computation using Maple software and C++ language have been carried out to illustrate some novel and interesting patterns of numbers in these arrays.

• English Language & Literature Teaching
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• no.6
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• pp.75-88
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• 2000

There are many reasons why foreigners have difficulties learning English. In addition to the difference between English and the learner's grammar, the large number of irregularities found in English become another obstacle to learning English. Understanding the difference and the irregularities will help us not only have a good command of English but also teach English more effectively. Many irregular or alternating patterns, or even anomalies in Modern English are the results of historical changes. In this paper, I would like to focus on some of the irregular or alternating patterns found in different components of the grammar of English and to show how they can be accounted for historically. Through this study, I would like to show that the irregular patterns and anomalies in English were once regular and systematic, they have deviated from the regular patterns of the grammar as time has gone by, and they have survived in Modern English as irregular and alternating patterns. Many of the irregular or alternating patterns can be traced back by phonological, morphological and/or semantic changes in the history of English. Finally, by looking at language history, we can hold a more tolerant view on many anomalies present in English.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1073-1077
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• 2005

In this study, wave pressure is calculated by using irregular waves in front of a breakwater. In the numerical model, the Reynolds equations are solved by a finite difference method and $k-{\varepsilon}$ model is employed for the turbulence analysis. To track the free surface displacement, the volume of fluid method is employed. The results of two cases present that wave pressure change due to irregular wave similar to wave height of irregular wave. It is observed that wave pressure of Case 2 more bigger than wave pressure of Case 1 at the same position.

• Journal of Power System Engineering
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• v.16 no.1
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• pp.84-90
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• 2012

In unmanned vehicles' navigation, the shapes of obstacles are generally irregular and complex. The motion of vehicles based on the range sensor system such as ultrasonic sensors or laser sensors can be unstable due to the irregular shape of the obstacles. In this case, to generate stable trajectory of unmanned vehicles equipped with range sensors, we need an approach that can simplify an obstacle's irregular shape information. In this paper, we propose the trajectory generation algorithm that an vehicle can stably navigate in the environments where irregular shaped obstacles are scattered. The proposed method is verified through the analysis of vehicle's trail and direction data acquired by simulations and implementations.