• Journal of Bio-Environment Control
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• v.10 no.3
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• pp.148-154
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• 2001

The uplift capacity of a pile for improving the wind resistance of the 1-2 W type plastic film pipe on greenhouses was tested using the plane and corrugated piles with various shapes and diameters. First, the resistant uplift capacity was measured by using the uplift loading on plane piles. As the uplift loading on plane piles increased, the resistant uplift capacity also increased until the loading was reached to ultimate uplift capacity. After ultimate uplift capacity was appeared the uplift displacement, the uplift capacity was decreased gradually. Secondly, the resistant uplift capacity was measured by using the uplift loading on corrugated piles. After the uplift capacity was reached the uplift displacement, the uplift capacity was continually increased or decreased. In general, the ultimate uplift capacity was independent of pile shapes, pile diameter length, and embedded pipe depth. However, the ultimate uplift capacity of a corrugated pile was twice more than that of a plane pile without regard to its diameter and embedded depth. The ultimate uplift capacity per unit pile area was increasing in deeper embedded depth. However, the longer a pile diameter was, the less ultimate uplift capacity. The uplift capacity of a plane pile, used in conjunction with the design wind velocity (26.9m.s$^{-1}$ ) of the project area, was unsatisfiable without regard to diameters and embedded depths of piles, while most of corrugated piles were well appeared uplift capacity under various experimental conditions.

• Journal of the Korean Geosynthetics Society
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• v.16 no.4
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• pp.151-161
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• 2017

A TSL (Thin Spray-on Liner) has a higher initial strength and faster construction time than conventional cementitious shotcrete. Because of its high adhesion and tensile strength, the TSL reinforced concrete show a characteristic like composite materials. In this study, to consider an application to the conventional design method, ASD (allowable stress design), numerical study was used. In the numerical analysis, material and contact properties were adopt from previous studies. Then a thickness of concrete in the tunnel was evaluated with the TSL reinforced case by the ASD concept. In other words, bending compressive stress, bending tensile stress and shearing force of the concrete were considered to determine a thickness of concrete lining by the given boundary conditions. From the numerical analysis, there was no tendency to show by the ASD because the ASD is based on the elastic theory while the TSL typically contributes to reinforcement after yielding.

• Journal of the Society of Naval Architects of Korea
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• v.30 no.1
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• pp.125-133
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• 1993

Most studies on the vibration analysis of a beam-column with ends elastically restrained and various intermediate constraints have been based on the Euler beam theory, which is inadequate for beam-columns of low slenderness ratios. In this paper, analytical methods for vibration and dynamic sensitivity of a Timoshenko beam-column with ends elastically restrained and various intermediate constraints are presented. Firstly, an exact solution method is shown. Since the exact method requires considerable computational effort, a Rayleigh-Ritz analysis is also investigated. In the latter two kinds of trial functions are examined for comparisions : eigenfunctions of the base system(the system without intermediate constraints) and polynomials having properties corresponding to the eigenfunctions of the base system. The results of some numerical Investigations show that the Rayleigh-Ritz analysis using the characteristic polynomials is competitive with the exact solutions in accuracy, and that it is much more efficient in computations than using the eigenfunctions of the base system, especially in the dynamic sensitivity analysis. In addition, the prediction of the changes of natural frequencies due to the changes of design variables based on the first order sensitivity is in good agreements with that by the ordinary reanalysis as long as the changes of design variables are moderate.

• Korean Institute of Interior Design Journal
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• v.23 no.4
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• pp.23-31
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• 2014

In this study, in order to analyze customers' space satisfaction, ten modern high-class Korean restaurants, five in New York and another five in Seoul, that were opened or remodeled after 2008 were selected and satisfaction characteristics survey of 197 customers who use these Korean restaurants was conducted by using Likert 5-point scale. The study results(a high reliability was obtained showing the Cronbach's alpha coefficient of average 0.895 for all questions) were analyzed for the frequency, percentage, mean, etc. and the mean between groups were comparatively analyzed by conducting the t-test, Duncan's test by using the SPSS 18.0 statistical program. The results are as follows. First, the results of customers general characteristic comparative analysis, all the Seoul and New York customers have comparatively high academic ability, high income and eating-out expenses. The main customers in Seoul were the women in their thirties and forties while those in New York were mainly in their forties and fifties both men and women at similar rate. Second, as to the satisfaction with the interior, the satisfaction with finishing materials was little higher in New York as Seoul (3.30 points) and New York (3.86 points). The satisfaction with color was relatively higher in Seoul (3.66 points) and relatively lower in New York (3.18 points). As the satisfaction with furniture and decorating accessories was relatively lower in both Seoul (3.10 points) and New York (3.48 points). The satisfaction with space size in Seoul (the total space size: 3.99 points, private space size; 3.90 points) was relatively higher than that in New York (the total space size: 3.46 points, private space size; 3.28 points). The satisfaction with interior and exterior in both Seoul (exterior: 3.63 points, interior: 3.40 points) and New York (exterior: 3.28 points, interior: 3.39 points) were average. For the satisfaction of environment, Seoul (3.42 points) was slightly lower than that of New York (3.56 points). Third, the result of customers' satisfaction in Seoul and New York showed no commonality. Therefore in order to be renewed as the Korean restaurants with high customer satisfaction, it is expected that the Korean restaurants located in Seoul and New York need to plan the space by considering their customers' characteristics and satisfactions.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.38 no.4
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• pp.11-17
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• 2001

In this paper, we propose a polarity decision carrier recovery algorithm for high order QAM(Quadrature Amplitude Modulation), which has robust and large frequency acquisition performance in the high order QAM modem. The proposed polarity decision PD(Phase Detector) output and its variance characteristic are mathematically derived and the simulation results are compared with conventional DD(Decision-Directed) method. While the conventional DD algorithm has linear range of $3.5^{\circ}{\sim}3.5^{\circ}$, the proposed polarity decision PD algorithm has linear range as large as $-36^{\circ}{\sim}36^{\circ}$ at ${\gamma}-17.9$. The conventional DD algorithm can only acquire offsets less than ${\pm}10\;KHz$ in the case of the 256 QAM while an analog front-end circuit generally can reduce the carrier-frequency offset down to only ${\pm}100\;KHz$. Thus, in this case additional AFC or phase detection circuit for carrier recovery is required. But by adopting the proposed polarity decision algorithm, we can find the system can acquire up to ${\pm}300\;KHz$at SNR = 30dB without aided circuit.

• Journal of Korea Water Resources Association
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• v.36 no.2
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• pp.273-284
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• 2003

In this paper, the reasons of damages and the case study are review in which bridge pier with debris accumulation, and safety Influence factors by debris around the bridge piers are review. Also experiment Is conducted for the characteristic of flow around piers by different area and angle of debris and the basic characteristics was review for safe design of bridge and embankments. As result of review of several standards of design, hydraulic structure's freeboard is simply decided by discharge, so it needs more detail standards. And as result of experiment, in the case of that water depth is deep and velocity is slow, variation of water depth Is more increase as increasing of debris. Therefore the variation regime of flow characteristics like velocity and water depth by debris is more large in the stream of small or medium size, which streams have large water depth and slow velocity so Froude Number Is expressed as small in the flood. Also when Froude Number is about 0.5, the water elevation is over freeboard in the standard if the debris over 20%. Therefore when hydraulic structure is constructed in the stream of small or medium size, it need to conduct more detail experiments about influence of debris, distribution of velocity and variation of elevation, and than the more safe freeboard will be presented using the experimental results.

• Korean Journal of Food Science and Technology
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• v.44 no.4
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• pp.422-427
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• 2012

A giant squid has not been utilized in the manufacture of the surimi-based product because of its strong fishy smell and weak gel forming ability. In this study, Amorphophallus konjac flour (AKF) was used to improve the quality of giant squid surimi-based products. The response trace plots showed that the gel texture and water retention ability (WRA) of surimi gel increased as the contents of AKF and surimi increased, whereas the water content decreased. Meanwhile, the whiteness of surimi gel increased as the contents of water and surimi increased, and AKF content decreased. Based on a sensory evaluation, giant squid surimi-products with AKF was inferior in color and taste compared to commercial surimi-based products, This inferiority could be improved by the addition of seasoning ingredients such as sweeteners. AKF successfully removed the fishy smell and improved the surimi gel properties. Therefore, AKF could be used as a food ingredient in surimi-based products.

• Journal of the HCI Society of Korea
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• v.13 no.3
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• pp.17-33
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• 2018

Humans process aesthetic functions of objects such as form, size, color, and texture through vision, while at the same time observe them with a symbolic function by a new psychological interpretation based on their past experience. Therefore, it is more important to study and understand the thoughts and psychological influences of how humans perceive with their eyes than what humans simply look with them. With this research purpose in the background, this study will demonstrate in detail the cognitive characteristics of analog and digital images as a symbolic function with a "formative" point of view. Five hypotheses were established, which were proven through the following tests: smartphone, most frequently used in our daily lives, is simplified to a two-dimensional line drawing form, which is set to instances where the R(radius) is applied to the horizontal line of the two-dimensional form of smartphone, where Run-in-R(radius) is applied, and R(radius) rounding is applied to the edges of those shapes. The shapes were combined to form 12 pairs, which was used in a test to the test subjects. As a result, some human characteristics were observed; in specific, some helped prove objectively how humans perceived analog and digital images as psychologically stronger as a symbolic function. If people's thoughts and feelings gained through such study could be stored in database as one value and be provided to product designers, I believe it could be developed into design form as a basic emotional design that consumers desire.

• Korean Journal of Construction Engineering and Management
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• v.19 no.4
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• pp.102-110
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• 2018

The study analyzed the effects of the floor plan characteristics on the apartment price under the national housing size in 3 Gangnam districts for decades, the primary apartment markets in Korea. The analysis showed that the storage spaces such as kitchen, warehouses and dressage rooms have a positive effect on the price. Especially, the highly opened space with three-side open plan and the one with the unified type of livingroom, diningroom and kitchen have shown the strong effect on the price. For the kitchen spaces, the I-shaped kitchen tends to be more expensive while a centered living room has a positive effect on the price. These findings have an academic significance as the direct effects of plan characteristics on price has been examined unlike prior research focused on the analysis of trend, basic statistics, and satisfaction level. It is noteworthy that these research finding has identified the productive implication for the future floor plan design and pricing and also be implemented in the purchasing decision making by buyers in the housing market.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.3
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• pp.399-405
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• 2011

In this paper, we present the design of Q-band LC VCO and injection locking buffer for 77 GHz automotive radar sensor using 130 nm RF CMOS process. To improve the phase noise characteristic of LC tank, the transmission line is used. The negative resistance by the active device cross-coupled pair of buffer is used for high output power, with or without oscillation of buffer. The measured phase noise is -102 dBc/Hz at 1 MHz offset frequency and tuning range is 34.53~35.07 GHz. The output power is higher than 4.1 dBm over entire tuning range. The fabricated chip size is $510{\times}130\;um^2$. The power consumption of LC VCO is 10.8 mW and injection locking buffer is 50.4 mW from 1.2 V supply.