• Journal of Electrical Engineering and Technology
• /
• 제8권1호
• /
• pp.190-196
• /
• 2013

This paper proposes a new guidance law, which considers the Field of View (FOV) of the seeker when a missile has a strapdown seeker mounted instead of a gimbal seeker. When a strapdown seeker, which has a narrow FOV, is used for tracking a target, the FOV of the seeker is an important consideration for guidance performance metrics such as miss distance. We propose a new guidance law called hybrid guidance (HG) to address the shortcomings of conventional guidance laws such as proportional navigation guidance (PNG), which cannot maintain lock-on conditions against high speed targets due to the narrow FOV of the strapdown seeker. The aim of the HG law is to null miss distance and to maintain the look angle within the FOV of the strapdown seeker. In order to achieve this goal, we combine two guidance laws in the HG law. One is a PNG law to null the LOS rate, and the other is a sliding mode guidance (SMG) law derived to keep the look angle within the FOV by employing a Lyapunov-like function with a sliding mode control methodology. We also propose a method to switch these two guidance laws at certain look angles for better guidance performance.

• 한국치위생학회지
• /
• 제13권1호
• /
• pp.146-157
• /
• 2013

Objectives : The purpose of this paper is to analyze the effects of short-term oral health care on children at community care centers, in order to allow them to maintain good oral health. Methods : The SPSS (Statistical Package for Social Science), Window Version 18.0 was used to analyze the data for the children's present conditions of oral health; their ability to maintain good oral health; their general knowledge about oral health; changes in their oral health awareness; habit formations concerning oral health; and the satisfaction level of oral health education. Results : 1. While the average number of teeth before the program is 19.84(6.19), that of teeth after the program is 21.33(6.10). 2. Average test scores on oral health information of post-program are improved more than those of pre-program. 3. The 8th measurement of O'Leary plaque index is 3.27, which shows significant changes. 4. Satisfaction level with the program is 4.75(0.45), which shows that children are satisfied with the program. Conclusions : The paper shows that in order to maintain the oral health of children at community care centers, their habit formation and practice for the oral health is important. It also shows that cooperation among communities and public health centers is important to develop various oral health education programs like the program.

• 동굴
• /
• 제59권
• /
• pp.21-36
• /
• 1999

Most scholars calssify caves into natural resource, but caves possess values of natural and human resource, mix up the features of natural resources and human resources. Now, caves are distributed 260 in Korea. Seongryu Cave is showed in 1967 for the first time, till 1997 12 caves is opened to tourist. But since 1996 the 12 show caves of all is not launched the safety and environment-protection check-up adduced reason for IMF. Then caves must maintain environment of the normal temperature, humidity and dark. But the environment of caves are destroyed by tourism development. Thus to maintain environment of caves, it used to consider the counterplan as follows in restraint of the environmental change. Firstly, in case of development work to open caves, it must keep up with the prototype. Secondly, it must establish a freight depositary to prevent the influence of the caves's stain and damage due to tourist's objects. Thirdly, to maintain the normal temperature and humidity, it must install artificial poultice equipment of the inner parts of caves. Fourthly, in order to prevent the occurrence of $CO_2$, it must assessment of the optimum number of the greatest stayer. Fifthly, the control of closure for a given period of time is useful of the restoration to the cave's original state. Sixthly, by means of make narrow entrance, it should not influence the outer's air on the inner parts on caves. Seventhly, to keep the temperature of the inner part of caves, the lightening should be maintained moderately considering the convenience of a tour. Eightly, when water-proof cables for the lightening bulbs are connected each other, silicon tape is suitable and circuit breakers should be installed at the diverging points of the cables. Ninthly, the direction and angle of the lightening must be changed periodically to prevent green-pollution at the lightening spot. Lastly, when facilities and arrangements are equipped, corrosive materials should be excluded if circumstances allow.

• 정보관리학회지
• /
• 제20권2호
• /
• pp.241-261
• /
• 2003

전자기록관리시스템은 전자기록이 자생적으로 갖고 있는 취약성과 가변성과 같은 특성 때문에 전자기록의 진보성 유지 측면을 충분히 반영시켜야 한다. 복제와 변조가 수월하고 장기보존 시포맷변환을 시켜야 하는 전자기록에 대한 진보성 유지는 도전하기 어려운 과제이기는 하나 정확한 역사 기술의 전제가 되는 기록으로서의 역할을 수행하기 위해서는 절대로 회피할 수 없는 과제이기도 하다. 따라서 본 연구는 전자기록의 진본성 유지를 위한 전략을 검토함으로써 향후 신뢰할 수 있는 전자기록관리시스템을 개발하는데 도움을 주는것을 목적으로 하여, 우선 기록 및 전자 기록의 의미, 진본성 그리고 진본성 평가를 위한 요건을 소개하였다. 또 시스템에서 전자기록의 진본성을 유지하기 위한 원칙, 전자기록의 진본성에 대한 오디트 트레일이 가능하게 하는 지적 정보 기술 방안과 시스템에서 구축해야 할 자본성 유지 메커니즘을 제안하였다. 마직막으로 전자 기록의 진본성 유지와 관련하여 시사점을 제시한 전자기록 관련 시스템 표준을 살펴보았다.

• 산업경영시스템학회지
• /
• 제40권4호
• /
• pp.96-104
• /
• 2017

A one-shot system (device) refers to a system that is stored for a long period of time and is then disposed of after a single mission because it is accompanied by a chemical reaction or physical destruction when it operates, such as shells, munitions in a defense weapon system and automobile airbags. Because these systems are primarily related with safety and life, it is required to maintain a high level of storage reliability. Storage reliability is the probability that the system will operate at a particular point in time after storage. Since the stored one-shot system can be confirmed only through inspection, periodic inspection and maintenance should be performed to maintain a high level of storage reliability. Since the one-shot system is characterized by a large loss in the event of a failure, it is necessary to determine an appropriate inspection period to maintain the storage reliability above the reliability goal. In this study, we propose an optimal inspection policy that minimizes the total cost while exceeding the reliability goal that the storage reliability is set in advance for the one-shot system in which periodic inspections are performed. We assume that the failure time is the Weibull distribution. And the cost model is presented considering the existing storage reliability model by Martinez and Kim et al. The cost components to be included in the cost model are the cost of inspection $c_1$, the cost of loss per unit time between failure and detection $c_2$, the cost of minimum repair of the detected breakdown of units $c_3$, and the overhaul cost $c_4$ of $R_s{\leq}R_g$. And in this paper, we will determine the optimal inspection policy to find the inspection period and number of tests that minimize the expected cost per unit time from the finite lifetime to the overhaul. Compare them through numerical examples.

• 가족자원경영과 정책
• /
• 제16권4호
• /
• pp.45-68
• /
• 2012

This study performed an analysis to determine if an individual can maintain the current consumption, in the case of a single retired elderly person's household using the accumulated assets. Assets are divided into three types, based on the behavioral economics life cycle hypothesis : financial assets, real assets excepting residential assets, and residential assets, and it is assumed that these assets were used on a step-by-step basis. Also, if the assets were sufficient, the maximum withdrawal amount was calculated. The results of the analysis are as follows. First, the monetary assets were sufficient to cover the cost of living for 2.7 years, 6.4 years by using the real assets of the non-occupied housing, and 26.3 years in the case of residential property. Second, in the case of preferentially using the financial assets, 4.4% of the sample households were able to cover the cost of living. Households that were not able to cover the cost of living used the next-stage assets, real assets of the non-occupied housing. Households that were not able to cover the cost of living by financial assets liquidated the real assets with the exception of residential assets and used these to cover the cost of living. A total of 4.8% of the households were able to maintain the current cost of living through the second stage and 25.5% supplemented their funds by using residential assets. That is to say, 35% of the sample households were able to maintain the current level of living by using their assets.

• 말소리와 음성과학
• /
• 제6권2호
• /
• pp.55-64
• /
• 2014

This study measured formant bandwidths of profound hearing impaired children and examined the characteristics of their articulation. For this study, 10 cochlear implanted children(CI), 10 hearing aid children(HA) and 10 normal hearing children(NH) were asked to read 7 Korean vowels(/ɑ, ʌ, o, u, ɯ, i, ɛ/). The subjects' readings were recorded by NasalView and analyzed by Praat. The analysis of the formant bandwidths explains the degree of vocal fold opening and the characteristics of radiation. Through the analysis of formant bandwidth, we can see that the hearing-impaired maintain vocal fold tension when they speak high vowels and characteristics of radiation. Narrower B1 means better maintain vocal fold tension, wider B2 means more front and wider B3 means the rounder lips. CI's B1 was widest and NH's was narrowest. And females' B1 was wider than males'. Among vowels, B1 of /a/ was widest, and B1 of /i/ was narrowest. In the case of B2, HA and NH's B2 was wider than CI's. Females' B2 was wider than males'. And B2 of /i/ was widest, and B2 of /ʌ/ was narrowest. In the case of B3, NH's was widest, and CI's was narrowest. Males' was wider than females'. Among vowels, B3 of /o/ was widest, and B3 of /ɛ/ was narrowest. As a result, first, through the analysis of B1, we can find that NH and males could better maintain vocal fold tension than the hearing-impaired or females, and all children articulate /i/ with vocal fold tension than other vowels. Second, through the analysis of B2, NH and HA articulate vowels with the weaker rounded than CI does. And females articulate vowels with the weaker rounded than males do. Third, through the analysis of B3, NH articulate vowels with the rounder than HA or CI do, and males articulate vowels with the rounder than females do. Through the results, we can expect that the analysis of formant bandwidth will be applied to the therapy of articulation for the hearing-impaired with hearing aids or cochlear implant.

• 건축역사연구
• /
• 제27권2호
• /
• pp.101-112
• /
• 2018

The study on the government office building in Chungcheong Suyeong(忠淸水營) is very rare. How were the Gaeksa(客舍) and Dongheon(東軒) which are representative government office buildings in Suyeong, maintained and what was the aspect of it, while passing through the upheaval period of the end of Joseon(朝鮮)? And where was the original place and was there any change in use? It is so regrettable that these subjects were not figured out yet. So I thought it is very important task to figure out its actual aspect by investigating the maintain state of the Gaeksa and Dongheon and the change of their places. So this study examined the related historical records and, based on it, analyzed "Ocheon GoonJi(鰲川郡誌)" in various view points. Through this analysis, this study could figured out the maintain aspect of the gaeksa and dongheon and the change of their places, and be able to deduce the other change of the government office building. This study could assume the places of each government office buildings by comparing this investigated result and the analyzed result of the original cadastral map in various view points. As the result of the study done by this method, this study confirmed the maintain state of the Gaeksa and Dongheon in Chungcheong Suyeong while passing through the upheaval period of the end of Joseon. And this study figured out the places of the Gaeksa and Dongheon, and be able to confirm their places by the lot number on the original cadastral map. Along with this, this study could estimate Jo(趙) family's confliction with the residents at that time by verifying the lot numbers of the Sapaeji(賜牌地) which this family received from the government. And among the names of the government office buildings, for the Jangkyocheong(將校廳) which is in dispute because of the name, this study figured out that the author of "Ocheon GoonJi" made a mistake in writing Dongheon.

• 한국병원경영학회지
• /
• 제22권4호
• /
• pp.87-101
• /
• 2017

[Purpose] This study aims to classify of healthcare decline and analyze the corresponding health outcomes among cities in Korea. In pursuing the above, this paper gives the particular attention to draw policy implications. [Methodology/Approach] Public healthcare data of 81 cities between 2014 and 2015 was obtained from the National Medical Center of Korea. A matrix analysis, t-test, ANOVA and multivariate regression were applied. [Findings] The study results indicated that declining cities tend to have the most healthcare resources, compared to growing or maintaining cities. However, accessibility to healthcare appeared to be lower in declining cities. Based on the classification of cities on healthcare decline, 42 out of 81 cities were categorized as a maintain/improvement group, while 39 cities were characterized as decline/depression. The group with a decline/depression type has significantly more healthcare facilities than maintain/improvement type. In contrast, maintain/improvement cities indicated lower incidence of morbidity and mortality than decline/depression cities. Lastly, according to the multivariate regression analysis for the healthcare outcomes by the type of healthcare decline, incidence of morbidity and mortality tended to decrease as the number of healthcare workers, the proportion of people who have healthcare accessibility, and the Timely Relevance Index increased regardless of the number of medical facilities including hospital beds and special beds. [Practical Implications] In conclusion, focusing on the improvement of healthcare accessibility as well as staffing, rather than expanding facilities is essential to set the healthcare policies.

• 융합정보논문지
• /
• 제11권12호
• /
• pp.221-228
• /
• 2021

본 연구는 염색 과정에 유기산을 이용한 후처리를 적용하여 염색의 지속성을 높이고 모발의 손상을 억제하고자 하였다. 체리레드와 블루실버 색상으로 탈색모를 염색하는 과정에 succinic acid와 tartaric acid를 이용하여 후처리 하고 염색된 모발의 색 지속성, 인장강도, 기공, 표면 특성을 알아보았다. 반복적인 샴푸 세척을 진행한 후 모발의 색상변화를 측정한 결과 succinic acid와 tartaric acid 실험군은 대조군 보다 효율적으로 모발의 색상을 유지할 수 있었다. 염색 후 모발의 손상도를 측정한 결과, succinic acid와 tartaric acid 실험군은 대조군 보다 높은 인장강도, 낮은 기공도, 매끄러운 표면 특성을 나타내어 모발 보호 효과를 나타냈다. 특히, tartaric acid는 succinic acid 보다 높은 효율로 염색모의 색을 지속시키고, 모발을 보호할 수 있었다.