• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.2
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• pp.65-74
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• 2012

This paper aimed at the development of a unified wireless control system in order to control various forms of vibration of bridges. This unified wireless control system unified all different systems each of which functioned for difference purpose such as measurement, analysis, judgement, and control of data acquired from the movement of structure. It was designed to control structures with feedback which was returned according to each different situation after analyzing various signals measured about the structure. In this system, every information in each step from measurement to control was wirelessly transmitted to its central system so that a manager was able to effectively monitor the whole process. Just for the case when any system control need to intervene occurred, a graph user interface was designed for better access. In order to evaluate its basic performance, an experiment was carried out to see how signal input and output were done by comparing its results with those of a wired system. On the basis of the experiment, a vibration control experiment was performed on a model of cable-stayed bridge to see if the unified wireless control system worked well in realtime. This was carried out under four conditions, and the graph and quantitative result under each condition were compared each other. All experiments proved that the unified wireless control system functioned as well as the wired one in terms of its basic performance and vibration control.

• Resources Recycling
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• v.26 no.5
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• pp.54-60
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• 2017

In this study, we investigated the effect of $TiCl_4$ injection time on the Kroll reaction at a given weight ratio of $TiCl_4$ and Mg. The reduction reaction was investigated by measuring the temperature change according to $TiCl_4$ injection time and observing the cross section and appearance of the Ti sponge after the reaction. The temperature increment due to Kroll reaction heat generation was found to be linearly proportional to the $TiCl_4$ feed rate. In the graph of $TiCl_4$ injection time and reduction tank temperature, initial temperature peaks were observed irrespective of the injection conditions. This is interpreted to mean a temporary interruption of reaction due to $MgCl_2$ formation after the initial Kroll reaction. In addition, when the cross section of the sponge was observed, a large amount of spherical Mg particles was observed in $MgCl_2$. We can infer that this is the process of continuously feeding the unreacted Mg surface, so that a continuous Kroll reaction takes place. The sponge appearance showed that the coalescence or growth of the Kroll reacted Ti particles can be controlled by the cooling rate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.726-732
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• 1997

The purpose of this study is to develop a software program to diagnose and assess status of dietary intake obtained using 24-hour dietary recall method. This program consist of four functions. The first function is assessing tile general status of the body such as ideal body weight, obesity measure, activity expenditure energy and total energy requirement by the analysis of age, height, weight and the degree of activity. The second one is calculating the intake number of food classified by the food group and evaluating the status of food intake by comparing them with the number of standardized intake in recommended dietary allowances for Koreans,6th revision. Third one is calculating energy and nutrient intakes contributed by the food group in dietary intake and evaluating the status of dietary intake by comparing the nutrient intake with the recommended dietary allowance for Korean, especially calculating and evaluating the status of dietary fat intake. The fourth function is calculating and evaluating the status of nutrient intake and nutrients energy Percent contributed by three regular meals and at least one in-between-meal snack. The results are displayed as tabular forms and graphical forms on the computer screen.

• The Journal of Korean society of community based occupational therapy
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• v.4 no.2
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• pp.11-22
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• 2014

Objective : The purpose of this study is to investigate the effect of mental practice with task activities through upper limbs movement speed and accuracy in ideomotor apraxia patient. Methods : As a single subject research design with multiple baseline across individuals, the patients were two ideomotor apraxia patients, employed in this study. The employed program included receiving mental practice and task activities, measuring change of the total performance times, time to put down the last cups and amount of water in cups for 4 weeks, including baseline and intervention periods. The subject were measured by Ideomotor apraxia test and MFT were analyzed. The analyses were performed using visually and two-standard deviation band method. Results : All subjects were a reduction in symptoms of apraxia, but noticeable change in upper limbs function was not there. Total time of performance from 376.67 to 355.24 seconds, 391.33 seconds to 434.60 seconds, reduced. Put down the cup of performance time from 15.67 to 13.30 seconds, 20.80 seconds to 10.73 seconds, reduced. The amount of water transferred from 52.38ml to 49.70ml, 50.89ml to 50.09ml, all results were closer to 50ml. Conclusion : As a result of this study, mental practice with task activities can be an effective method to ideomotor apraxia patients. This study would serve a fundamental data on ideomotor apraxia patients to the further studies.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.9
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• pp.1575-1583
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• 2008

Wireless sensor network has merit of low-power, low-cost and self-organization network, so there are many researches substituted for existing wire network. As structure reinforcement work need a high accuracy, many sensors are installed in structure and connected with data logger for monitoring. However this wire data logger method takes a long time to install wires and installed wires obstruct to work. Additionally, wire data logger method represent sensor data by only numeric and graph, it is not able to support a rapid decision-making for working. To resolve wiring problem and support decision-making, we designed and implemented the monitoring system based in wireless sensor network. For verifying performance, accuracy and availability, we simulated and tested our system in real field. Consequently, wireless sensor network method is easier to install and deploy than wire data logger method, user is able to monitor instinctively and overall by 3D representation of structure and sensors, and it show not only accuracy but also performance for many sensors.

• Food Engineering Progress
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• v.14 no.1
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• pp.35-40
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• 2010

Electronic nose (E-nose) was assessed for grading pungency of powdered red pepper. Complex pretreatments are not required for flavor analysis unlike HPLC or Scoville tests. Mild and pungent taste of powdered red pepper were mixed at various concentrations of 0, 25, 50, 75, and 100%. Those were analyzed using mass spectrometer-based E-nose. Discriminant function analysis (DFA) was conducted on E-nose data. The $R^{2}$ and F-value of dicriminant function first score (DF1) were 0.9946 and 355.65, respectively, when the samples were separated by a relative degree of pungent taste. DF1 value decreased with increasing the amount of powdered red pepper with a pungent taste. It is similar to the increase in the concentration of capsaicin. Increasing the amount of red pepper powder, dicriminant function second score (DF2) values were moved from the negative position into the positive position. The $R^{2}$ and F-value of DF1 were 0.9890, 165.17 and DF2 were 0.9219, 21.64. Also, the results by MS based E-nose agreed to that by HPLC. There is the potential to grade pungent taste of powdered red pepper using the E-nose.

• Korean Journal of Remote Sensing
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• v.14 no.4
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• pp.366-375
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• 1998

Optical characteristics of the yellow sand and their influences on the ocean color remote sensing has been studied using ocean color sensor SeaWiFS measurements. Two cases of April 18 and April 25, 1998, representing yellow sand and background aerosol, are selected for emphasizing the impact of high aerosol concentration on the ocean color remote sensing. It was shown that NASA's standard atmospheric correction algorithm treats yellow sand area as either too high radiance or cloud area, in which ocean color information is not generated. Optical thickness of yellow sand arrived over the East Asian sea waters in April 18 indicates that there are two groups loaded with relatively homogeneous yellow sand, i.e.: heavy yellow sand area with optical thickness peak around 0.8 and mild area with about 0.4, which are consistent with ground observations. The movement of the yellow sand area obtained from surface weather maps and backward trajectory analysis manifest the notion that the weak yellow sand area was originated from the outer region of the dust storm. It is also noted that high optical thickness associated with the yellow sand is significantly different from what we may observe from background aerosol, which is about 0.2. These characteristics allow us to determine the yellow sand area with an aid of atmospheric correction parameter. Results indicate that the yellow sand area can be determined by applying the features revealed in scattergrams of atmospheric correction parameter and optical thickness.

• Korean Journal of Remote Sensing
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• v.17 no.1
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• pp.85-97
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• 2001

The KT(Kauth-Thomas) and IHS(Intensity-Hue-Saturation) transformation techniques were introduced and compared to investigate fire-scarred areas with single post-fire Landsat 7 ETM+ image. This study consists of two parts. First, using only geometrically corrected imagery, it was examined whether or not the different level of fire-damaged areas could be detected by simple slicing method within the image enhanced by the IHS transform. As a result, since the spectral distribution of each class on each IHS component was overlaid, the simple slicing method did not seem appropriate for the delineation of the areas of the different level of fire severity. Second, the image rectified by both radiometrically and topographically was enhanced by the KT transformation and the IHS transformation, respectively. Then, the images were classified by the maximum likelihood method. The cross-validation was performed for the compensation of relatively small set of ground truth data. The results showed that KT transformation produced better accuracy than IHS transformation. In addition, the KT feature spaces and the spectral distribution of IHS components were analyzed on the graph. This study has shown that, as for the detection of the different level of fire severity, the KT transformation reflects the ground physical conditions better than the IHS transformation.

• Korean Journal of Social Welfare Studies
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• v.49 no.2
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• pp.5-38
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• 2018

The purpose of this study is to examine work-life balance by analyzing time schedules of married couple. The 2014 Korea Time Use Survey dataset was used for the analysis. Finally, 6,262 time diaries of 3,131 households were included in the analysis. The study used sequence analysis in particular, by applying the Lesnard(2014)'s dynamic hamming matching (DHM) method, which is useful for the time diary analysis where timing is a key factor. This study explored daily schedules of each man and woman according to 9 types of couple-combined work-schedules, which had been already derived by cluster analysis. The daily schedules were identified according to the activities divided as labor, housework, sleep, self-management, active leisure, passive leisure, and others. Here, time allocation was analyzed through various graphs showing average time amount and modal states by time period. Based on the analysis, it summarized that "long working hours as a main factor of work-life imbalance", "gender inequality of time use", "non-standard hours work impairing quality of life and "poverty of leisure time"as characteristics of work-life imbalance. Finally this study discussed the social policy implications to support work-life balance.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.96-97
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• 2019

최근 홍수파 또는 댐 및 보 등의 하천구조물과, 본류와 지류의 합류로 인해 발생하는 배수영향 등으로 하천에 고리형 수위-유량관계가 나타나 수위-유량관계식의 신뢰도가 저하된다고 판단되는 대하천 본류와 합류부 인근 지류에서 초음파유속계 측정결과를 지표로 활용하는 자동유량장치가 현재 58개소에 도입되어 운용되고 있다. 그러나, 최근 4대강 사업으로 다기능보 설치 등 하천의 수리적 특성이 변동하였고, 지류에서 주로 운용되는 수위-유량관계 기반 유량관측소에 본류-지류합류로 인한 배수영향으로 고리형 수위-유량관계가 형성될 경우, 지류 수위관측소를 자동유량관측소로 대체할 필요성이 제기되고 있다. 또한, 기존 자동유량관측소의 경우 홍수량이 기준이하로 나타날 경우 수위-유량 관계식으로 대체하는 경우도 있는데 적용기준이 명확하지 않다. 본 연구에서는 신규 자동유량장치 설치, 기존 수위관측소의 자동유량관측소대체, 자동유량관측소에서 수위-유량관계곡선의 활용 기준 마련 등을 명확하게 판단하기 위해 고리형 수위-유량관계 패턴을 분석하고 배수영향구간을 산정하여 제시하고 지류 수위관측소의 존속여부, 유량자료의 적절성을 판단할 수 있는 방법론을 제시 하고자한다. 이를 위해, 다기능보 설치 및 지류-본류로 인한 지류하천의 배수영향과 홍수파에 의한 고리형 수위-유량관계의 양상을 다양한 수문사상에 대해 분석하였다. 분석방법으로는 대상유역을 선정하고, 대상유역에 대한 부정류 모형을 구축하기 위해 HEC-RAS 모형을 사용하고, 대상유역에 대한 HEC-RAS 지형자료와 유량입력자료를 구축한다. HEC-RAS 부정류 모형 구축 후 다양한 본류와 지류의 유량을 가정하여 고리형 수위-유량 발생 패턴을 분석한다. 지류-본류 합류 영향의 경우, 본류영향의 유무를 고려하여 상승된 수위의 비율로부터 일정 유의수준을 두어 배수영향구간을 산정한다. 다기능보의 영향은 다기능보 설치 전후를 가정하여 영향을 분석한다. 본 연구에서는 시범구역으로 하류에 창녕함안보가 위치한 낙동강과 합류하는 남강과 하류에 달성보가 위치한 낙동강과 합류하는 금호강을 대상하천으로 하여 위 분석방법을 적용하였다. 분석결과 남강의 경우 지류 유량이 작은 경우에도 본류 유량이 상대적으로 큰 경우 배수영향에 의한 고리형이 나타났고, 다기능보에 의한 배수영향은 매우 적은 것으로 나타났다. 또한, 지류의 유량이 큰 경우 홍수파에 의한 고리형 관계도 발생함을 알 수 있었다. 금호강의 경우 또한 마찬가지로 본류의 유량에 의해 발생하는 고려형 관계가 지배적임을 알 수 있었다. 따라서 이러한 결과를 바탕으로 95%의 유의 수준을 기반으로 고리형 발생 여부를 확일할 수 있는 모노그래프를 남강, 금호강에 대해 작성하여 수위-유량관계 기반 유량 산정의 적절성을 판단하는 기준으로 제안하였다.