• Proceedings of the KSRS Conference
• /
• 2005.10a
• /
• pp.83-86
• /
• 2005

This paper presents a method for point-based 3D building reconstruction using LiDAR data and digital map. The proposed method consists of three processes: extraction of building roof points, identification of roof types, and 3D building reconstruction. After extracting points inside the polygon of building, the ground surface, wall and tree points among the extracted points are removed through the filtering process. The filtered points are then fitted into the flat plane using ODR(Orthogonal Distance Regression). If the fitting error is within the predefined threshold, the surface is classified as a flat roof. Otherwise, the surface is fitted and classified into a gable or arch roof through RMSE analysis. Based on the roof types identified in automated fashion, the 3D building reconstruction is performed. Experimental results showed that the proposed method classified successfully three different types of roof and that the fusion of LiDAR data and digital map could be a feasible method of modelling 3D building reconstruction.

• Journal of Fashion Business
• /
• v.6 no.6
• /
• pp.105-111
• /
• 2002

E-business has been regarded as new type of marketing channels and has been growing rapidly. The purpose of this study was to investigate textile sensibility depending on consumers' purchase experience of apparel product in e-business. The analyses of 202 questionnaires were conducted by frequency, mean, and standard deviation, and t-test using SPSS 10.0. Computer setting environment was 1280$\times$1024 resolution with 96 DPI (dots per inch) for this experiment. The results of this research were as follows: Melton (flat axis), habutae (thin axis), suede (wet axis), and terry (rustic axis) showed that there were no significant differences in textile sensibility regarding purchasing experience in the cyber apparel store. But oxford (hard axis) showed that purchasing experience group perceived less modern and smooth textile sensibility than no purchasing experience group. In case of linen (dry axis), purchasing experience group showed less modern textile sensibility. In case of muslin (soft axis), purchasing experience group had more flat and less soft textile sensibility than no purchasing experience group. In case of homespun (thick axis), purchasing experience group perceived less modern textile sensibility than no purchasing experience group.

• Journal of Biosystems Engineering
• /
• v.20 no.3
• /
• pp.217-225
• /
• 1995

This study was conducted to find design factors of spraying device of the boom sprayer for low volume application. Four types of nozzles(standard flat nozzle, drift guard nozzle, even flat nozzle, and hollow cone nozzle) were used for the spray characteristic experiment. Spray patterns of the nozzles were distinguished by the nozzle type, spray distance, and spray direction. The flow rate was proportional to the square root of spray pressure in all nozzles. Increased nozzle height improved spray distribution at reduced pressures and/or increased spacing. Distribution tended to improve as pressure increased within the range of pressures used for fan nozzles.

• Journal of the Korean Mathematical Society
• /
• v.36 no.1
• /
• pp.193-207
• /
• 1999

Let ${\gamma}$ : Ilongrightarrow R2 be a sufficiently smooth curve and $\sigma$${\gamma}$ be the affine arclength measure supported on ${\gamma}$. In this paper, we study the Lp - improving properties of the convolution operators T$\sigma$${\gamma}$ associated with $\sigma$${\gamma}$ for various curves ${\gamma}$. Optimal results are obtained for all finite type plane curves and homogeneous curves (possibly blowing up at the origin). As an attempt to extend this result to infinitely flat curves we give and example of a family of flat curves whose affine arclength measure has same Lp-improvement property. All of these results will be based on uniform estimates of damping oscillatory integrals.

• Journal of the Korean Vacuum Society
• /
• v.15 no.5
• /
• pp.475-484
• /
• 2006

The deformation, the stress distribution, and the contact pressure of gaskets used in sealing flanges of CF (Con-Flat) or IPD (Improved) type were calculated to investigate the possibility of analyzing and estimatimg the sealing performance under a given tightening condition for a specific flange system.

• Korean Journal of Child Studies
• /
• v.29 no.4
• /
• pp.15-26
• /
• 2008

This study analyzed the portrayal of adult characters in 176 picture books published in Korea by variables of character's external condition(sex, name, age and occupation), type(3-dimensional or flat), conflicts, and image. Standards for analysis of the picture books were devised by the researcher. Results showed that (1) adult male characters appeared much more frequently than female; they appeared most often without names and in order of older, middle aged, young adult. They appeared most often without occupations. (2) 3-dimensional characters appeared much more than flat ones. (3) Adult conflict situations were rare and were mostly interpersonal. They often resolved their conflicts by themselves. (4) The 20 kinds of images of the adult characters were mostly humorous, warm-hearted and attentive.

• The Transactions of the Korea Information Processing Society
• /
• v.5 no.7
• /
• pp.1943-1950
• /
• 1998

Irregular addressing scheme of gray scale control for the memory type flat panel plasma display is proposed in this paper. Opposed to the conventional addressing method. the scan electrodes are addressed in non-sequential manner. The addressing order for this irregular addressing is resolved to make the pixel duty factor above 90%. This addressing scheme can achieve the prolxJsed peformance regardless of the panel and cell structure and can be implemented without increasing the chive voltage, current or frequency .

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.15 no.1
• /
• pp.9-18
• /
• 2003

An experimental study was performed to investigate the turbulence intermittency measuring methods across the boundary layer in the transition region. A single type hot-wire probe was used to measure instantaneous streamwise velocities in laminar, transitional and turbulent boundary layer To estimate wall shear stresses on the flat plate, near wall mean velocities are applied to the principle of CPM. Distribution of intermittency factor is obtained by dual-slope method and compared to the results of four methods,$\'{u},\;\{U}$, TERA and M-TERA method. In these methods, M-TERA shows a good agreement in the near wall region. However, the result of M-TERA method shows that intermittency factor is underestimated in the outer part and outside of the boundary layer and the dimensional constant of M-TERA method should be changed appropriately depending on measuring point.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.24 no.10
• /
• pp.780-787
• /
• 2014

This paper experimentally deals with the vibration characteristics of flat ring transducers used for ultrasonic sensors and actuators. Radial vibration mode, which is the fundamental mode of a thin piezoelectric transducer, was measured by a laser in-plane vibrometer. An impedance analyzer was used to measure natural frequencies. The results measured by experiments verified theoretical predictions. The vibration characteristics of ring transducers were identified according to the outer diameter size. The shape of the fundamental mode is almost uniform but slightly decreases from the inner to the outer circumferential surfaces. The natural frequency of the fundamental mode decreases as the outer diameter increases. It appears that the ring type transducer is suitable to excite uniformly distributed vibration on a flat surface.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.11
• /
• pp.5365-5380
• /
• 2016

Estimation of signal-to-noise ratio (SNR) is an important problem in wireless communication systems. It has been studied for various constellation types and channels using different estimation techniques. Maximum likelihood estimation is a technique which provides efficient and in most cases unbiased estimators. In this paper, we have applied maximum likelihood estimation for systems employing square or cross QAM signals which are undergoing slow flat Rayleigh fading. The problem has been considered under various scenarios like data-aided (DA), non-data-aided (NDA) and partially data-aided (PDA) and the performance of each type of estimator has been evaluated and compared. It has been observed that the performance of DA estimator is best due to usage of pilot symbols, with the drawback of greater bandwidth consumption. However, this can be catered for by using partially data-aided estimators whose performance is better than NDA systems with some extra bandwidth requirement.