• Journal of the Korean Chemical Society
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• v.48 no.6
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• pp.645-653
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• 2004

The purpose of this study was to compare and analyze the cognitive levels of 11th grade students and those required in high school chemistry I textbooks standardized by the 7th national education curriculum. For this study, the cognitive development stages of 456 11th grade students were surveyed using short-version GALT (group assessment of logical thinking). Furthermore, 15 basic concepts were extracted from the contents on water and air, 2 units in chemistry I order to analyze the cognitive levels necessary for understanding high school textbooks, using CAT (curriculum analysis taxonomy). The results showed that 52.5% of the surveyed 11th grade students reached the formal operational level, 28.3% transitional levels, and 19.5% concrete operational levels. 68.9% of the academic high school students and 6.6% of the technical high school students reached the formal operational levels, and the ratio of formation was very different in each logics. As a result of the analyzing the cognitive levels needed for understanding chemistry I textbook contents, in spite of a change in national education curriculum, there were no great change in cognitive levels required by scientific concept except some inquiry activities. The cognitive levels in high school chemistry I textbooks by the 7th national education curriculum appeared higher than the cognitive levels of 11th grade student, but cognitive levels of inquiry activities were similar to the cognitive levels of the students. Chemistry teachers thought of chemistry I textbooks by the 7th national education curriculum as desirable because scientific concepts were reduced and a lot of real life materials were adapted. However, they pointed out a problem of difference in contents levels compared with chemistry I textbooks because scientific concepts were greatly reduced in chemistry I textbooks. The cognitive levels required in chemistry I textbooks still appeared higher than those of the students. Consequently, various teaching and learning methods and materials will have to be developed to be suitable for the students' cognitive levels.

• Journal of Digital Convergence
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• v.20 no.3
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• pp.349-357
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• 2022

Drum Set are representative instruments that use grips in modern popular music. Depending on how and how clearly you hold the basic grip, it also affects your performance ability. The purpose of this study is to analyze the characteristics, strengths, and weaknesses of each grip, derive the resulting complex effects, and present practical application plans to the drummers. The research method is largely divided into traditional and matched grips, and in detail, German, American, French, and hybrid styles are included to analyze the performance method utilized. It also refers to the grip method of all drummers from the 1930s to the present, which was registered in Drummer World, an overseas drum site. This study proposed several application plans by classifying and analyzing the most basic grip methods in drum set in detail. I was able to see that the performance impact was different depending on the grip, and I think it will be more helpful for future performances if I understand both the positive and adverse functions of each grip and play it.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.11
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• pp.2073-2078
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• 2016

Recently, there have been many research that recognize the situation using sensors. However, sensor data collection and analysis are still lacking in integration. This is because the data generated by the sensor is difficult to match in terms of metadata and units. Therefore, a methodology for efficiently using data generated from various sensors is needed. In this paper, we propose a system that recognizes the location through information generated from a moving iBeacon. This system constructs the ontology with the data that can recognize the exact position when the patient wearing iBeacon moves in the room. This maps standard items and sensor items, and stores the results of filtering the detected values as knowledge. the system can extract efficient location information by recognizing the value generated by moving the patient carrying iBeacon through the ontology. This can be applied not only to beacons but also to other sensors, and it can be applied variously according to the ontology configuration.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.20 no.5
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• pp.89-98
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• 2010

Wireless LAN (WLAN) is type of wireless service that has higher data transmission than current cellular networks. The usage is continually increasing. There are a lot of vulnerabilities in wireless network, due to the properties of the wireless environment, regardless of its popularity. IEEE announced the 802.11i security standard to solve these problems. The vulnerable point of messages used in the process of key distribution for 802.11i makes the target node attacked lose memory through continuous messages and blocks the legitimate WLAN service. In this paper, we proposed new schemes to solve this problem and compared our proposals with the current process. The proposed protocol eliminates the memory exhaustion problem on the client side by using methods for reduction of memory usage.

• Journal of Nutrition and Health
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• v.10 no.4
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• pp.84-91
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• 1977

엽산의 결핍은 대혈구성 빈혈(macrocytic and/or megaloblastic anemia)을 일으킨다. 체내에서 엽산은 합성될 수 없는 것으로 알려져, 식품을 통하여 섭취하여야 한다. 이에, 한국인 식생활의 기본을 이루고 있는 쌀, 콩 및 채소류의 식품에 포함된 엽산치를 미생물학적인 측정방법에 따라 분석하였다. Streptococcus faecalis보다 Lactobacillus casei미생물을 사용하여 측정한 방법이, 인간에게 이용될 수 있는 보다 정확한 엽산치로 밝혀졌다. 산화되기 쉬운 형태로 된 labile folate를 보호하기 위한 ascorbic acid의 첨가는, 각 식품에 포함된 엽산치를 증가 시켰다. 결합형으로 존재하는 polyglutamates를 유리형으로 하기 위하여 conjugase enzyme을 사용하였으며, 식품에 따른 화학적 조성은 주로 polyglutamyl form이나 각 식품에 따라 큰 차이가 있는 것으로 나타났다. Lactobacillus casei을 사용하여 측정된 각 식품의 엽산치는, 배추 34.5, 당근17.8, 오이 25.3, 가지 24.7, 쑥갓 76.5, 마늘 3.1, 파 40.2, 완두콩 68.7, 풋고추 27.1, 강남콩 66.9, 부추 64.1, 상치 39.3, 양파 4.3, 시금치 150.7, 호박 26.1, 무우 40.3, 백미 29.9 ug으로 각기 식품 100g 중에 함유됨을 보였다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.5
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• pp.277-286
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• 2010

In this paper we analyse radiation measurement method for UWB wireless system of the wideband low power frequency characteristics. In the radiation measurement environment we discuss RMS electric field strength, UWB PSD, UWB detect signal level, UWB noise signal collection etc.. also, we discuss power measure method of the CISPR16-1, low level e.i.r.p radiation measurement method. lastly we analyse consideration problem for the signal analyser of the UWB system.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.781-790
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• 2013

This research focuses on development of the conceptual cost estimation models for I.L.M box girder bridge. The current conceptual cost estimation for public construction projects is dependent on governmental average unit price references which has been regarded as inaccurate and unreliable by many experts. Therefore, there have been strong demands for developing a better way of conceptual cost estimating methods. This research has proposed three different conceptual cost estimating method for a P.S.C. girder bridge built with the I.L.M method. Model (I) attempts to seek the proper breakdown of standard works that are accountable for more than 95 percentage in total cost and calculates the amount of standard work's materials from the standard section and volume of I.L.M box girder bridge. Model (II) utilizes a correlation analysis (coefficient over 0.6 or more) between breakdown of standard works and input data that would be considered available information in preliminary design phase. Model(III) obtains conceptual estimating through multiple-regression analysis between the breakdown of standard works and all of input data related to them. In order to validate the clustering of coverage in the preliminary design phase, the variation of I.L.M cost coverage from multiple-regression analysis[model(III)] has been investigated which result in between -3.76% and 11.79%, comparing with AACE(Association for the Advancement of Cost Engineering) which informs its variation between -5% and +15% in the design phase. The model proposed from this research are envisioned to be improved to a great distinct if reliable cost date for P.S.C. girder bridges can be continually collected with reasonable accuracies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.342-349
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• 2019

We describe and anlayzes the methodology and implementation results of H / W configuration and signal characteristics analysis algorithm for analyzing equipment for analyzing OFDMA physical layer based on 802.16e. Recently, demand for signal analysis of instruments that analyze these signals with the development of digital communication signals is rapidly increasing. Accordingly, it is necessary to develop signal analysis equipment capable of analyzing characteristics of a broadband communication signal using a wideband digital signal processing module. In this paper, we have studied the basic theory of OFDMA in order to devise a device capable of analyzing characterisitcs of broadband communication signals. Second, the structure of OFDMA transmitter/receiver was examined. Third, a wideband digitizer was implemented. we design Wimax signal analysis algorithm based on OFDMA among broadband communication methods and propose Wimax physical layer analysis S/W implementation through I, Q signals. The IF downconverter used the receiver module and the LO generation module of the spectrum analyzer. Quantitative analysis result is obtained through the algorithm of Wimax signal analysis by I, Q data.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.11A
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• pp.1113-1119
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• 2007

In this paper, first, we proposed various possible candidate schemes for determining initial sleep window size and varying sleep window size in sleep mode for power saving class I of IEEE 802.16e. Then, we analyzed and compared the power saving performances of those schemes. The schemes used for the comparisons are EICV of IEEE 802.16e, and other comparable schemes such as EIED, EILD, LIED and LILD. Experimental results show that LILD and EIED outperform other comparable schemes. Especially, EIED shows the better performances for the case of high traffic intensity environments, while LILD does for the low traffic intensity case.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.3 no.2
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• pp.56-62
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• 1989

자연채광에 관한 에너지 해석을 하기 위해서는 주광조도를 예측하여야 하며, 주광조도를 예측하기 위해서는 천공상태를 추정할 수 있어야만 한다. 즉, 천공상태의 최저상태나 최소설계기준을 추정할 수 있어야만 자연채광에 의한 에너지 절약을 해석할 수가 있다. 천공상태를 추정하는데에는 CIE에서 개발한 정적 천공모델이 많이 이용되어 왔다. 그러나 천공은 정적광원이 아니라 시간에 따라 동적으로 변하고 있음으로 자연채광설계에서 에너지의 영향을 평가하기 위해서는 보다 융통성이 있는 천공모델이 요구된다. 따라서 이 논문은 그동안 동적천공을 나타낼 수 있도록 개발된 비표준천공의 추정방법, 동적 천공상태의 추정방법, 주광조도와 천공휘도의 추정방법, 주광의 유용성 평가방법 등을 비교분석함으로써, 앞으로 우리나라 기후상태에 적합한 자연채광용 천공모델을 개발하는데 기초자료화하였다.