• Proceedings of the KSRS Conference
• /
• 2004.10a
• /
• pp.220-223
• /
• 2004

Automatic image registration is an essential element of remote sensing because remote sensing system generates enormous amount of data, which are multiple observations of the same features at different times and by different sensor. The general process of automatic image registration includes three steps: 1) The extraction of features to be used in the matching process, 2) the feature matching strategy and accurate matching process, 3) the resampling of the data based on the correspondence computed from matched feature. For step 2) and 3), we have developed an algorithms for automated registration of satellite images with RANSAC(Random Sample Consensus) in success. However, for step 1), There still remains human operation to generate GCP Chips, which is time consuming, laborious and expensive process. The main idea of this research is that we are able to automatically generate GCP chips with comer detection algorithms without GPS survey and human interventions if we have systematic corrected satellite image within adaptable positional accuracy. In this research, we use SUSAN(Smallest Univalue Segment Assimilating Nucleus) algorithm in order to detect the comer. SUSAN algorithm is known as the best robust algorithms for comer detection in the field of compute vision. However, there are so many comers in high-resolution images so that we need to reduce the comer points from SUSAN algorithms to overcome redundancy. In experiment, we automatically generate GCP chips from IKONOS images with geo level using SUSAN algorithms. Then we extract reference coordinate from IKONOS images and DEM data and filter the comer points using texture analysis. At last, we apply automatically collected GCP chips by proposed method and the GCP by operator to in-house automatic precision correction algorithms. The compared result will be presented to show the GCP quality.

• The Journal of Korean Academic Society of Nursing Education
• /
• v.16 no.1
• /
• pp.101-110
• /
• 2010

Purpose: This study was a descriptive research study that investigates nurses' beliefs concerning death anxiety and spirituality. Method: The subjects were 150 nurses working at general hospitals located in Busan city. Data collection was carried out from October 15 to November 30, 2008. The study used a 'Death Anxiety Scale' and a 'Korean Spirituality Scale.' The collected data was analyzed for frequency, percentage, t-test, ANOVA, and Pearson's correlation coefficient with the SPSS/WIN 17.0. Result: The level of death anxiety of the subjects averaged 3.25. In each sub-factor, 'awareness of shortness of time' was the highest at 3.57 points. Spirituality level of the subjects averaged 3.51. In each sub-factor, meaning and purpose of life was the highest at 3.70 points. In differences of death anxiety followed by general characteristics, there were significant differences according to age, and educational level. For spirituality, followed by general characteristics, there were significant differences according to age, educational level, religion, working period, and understanding about death and spirituality. There was a weak inverse correlation among fear for accidents involved with death, total spirituality level and meaning, and purpose of life. Conclusion: Future research should examine relations between nurses' death anxiety and spirituality level through random sampling and research to check psychological and social variables that influence death anxiety and spirituality. Development of a program to lessen nurses' death anxiety and to raise their spirituality level would be prudent.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.13 no.6
• /
• pp.590-598
• /
• 2002

We have numerically analyzed the electromagnetic wave scattering from randomly rough dielectric surfaces by using the finite volume time domain (FVTD) method. We have then shown that the present method yields a reasonable solution even at low-grazing angle (LGA). It should be noted that the number of sampling points per wavelength should be increased when more accurate numerical results are required, which fact makes the computer simulation impossible at LGA for a stable result. However, when the extrapolation is used for calculating the scattered field, an accurate result can be estimated. If we want to obtain the ratio of backscattering between the horizontal and vertical polarization, we do not need the large number of sampling points. The results are compared with the experimental data.

• Journal of the Korean Data and Information Science Society
• /
• v.22 no.4
• /
• pp.619-630
• /
• 2011

In order to estimate an appropriate threshold and evaluate its performance for the data mixed with two different distributions, nine kinds of well-known classification accuracy measures such as MVD, Youden's index, the closest-to- (0,1) criterion, the amended closest-to- (0,1) criterion, SSS, symmetry point, accuracy area, TA, TR are clustered into five categories on the basis of their characters. In credit evaluation study, it is assumed that the score random variable follows normal mixture distributions of the default and non-default states. For various normal mixtures, optimal cut-off points for classification measures belong to each category are obtained and type I and II error rates corresponding to these cut-off points are calculated. Then we explore the cases when these error rates are minimized. If normal mixtures might be estimated for these kinds of real data, we could make use of results of this study to select the best classification accuracy measure which has the minimum error rate.

• Korean Journal of Health Education and Promotion
• /
• v.20 no.4
• /
• pp.67-78
• /
• 2003

This investigation was performed to summarize a few prominent features of smoking prevention program studies and to evaluate the quality of smoking prevention program studies using the Quality of Study Rating Form (QSRF). 24 school-based smoking prevention programs were subjected to an evaluation of study quality using QSRF. Study quality was 57.29 points out of 100 points on average, so it cannot be said that study quality was good. Most of the studies described the subjects and the intervention contents and intervention time. 50% stated where the intervention occurred specifically, 50% of the studies either discussed a specific theory that justified the use of one or more intervention methods, or they cited literature said to support the chosen intervention method. Only one study assigned subjects randomly to experimental groups or control groups and 50.0% of the studies showed baseline equality. There was no study where subjects were blind to being in the treatment or control group or where subjects were selected randomly by random sampling procedure. 79.2% of the studies had non-treated control groups and 20.8% of the studies had comparison groups with other treatments in the form of either other delivery methods or other contents. Sample sizes were larger than 21 in the experimental group for all studies. 75% of the studies stated face validity of outcome measure or cited from previous literature. 58.3% of the studies tested reliability and 45.8% reported the reliability measure was a figure of .70 or greater. There was no study where those rating outcomes were rated blind, because researchers generally collected data by themselves. Outcome measures were taken only after the intervention was completed and tests of statistical significance were generally referred to statistical method and p value in all studies. All studies met the criteria that follow-up was greater than 75%. The implications for the future studies were discussed.

• Journal of the Korea Computer Graphics Society
• /
• v.16 no.3
• /
• pp.41-48
• /
• 2010

Photon mapping is a traditional global illumination method using many photons emitted from the light source for photo-realistic rendering. However, this method needs a lot of resources to perform tracing of millions of photons. Progressive photon mapping solves this problem. Typical progressive photon mapping performs ray tracing at first to find the hit points on diffuse surface of objects. Next, light source repeatedly emits a small number of photons in photon tracing pass, and power of photons in each sphere that has a fixed radius with the hit points in the center is accumulated. This method requires less resources than previous photon mapping, but it spends much time for gathering enough photons since each of photons progresses through a random direction and rendering high quality image. To improve the method, we propose photon probing that calculates variance of photons in the sphere and controls radius of sphere. In addition, we apply cone filter in radiance estimation step for reducing aliasing at the edges in result image.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.1C
• /
• pp.28-36
• /
• 2009

Time-memory trade-off (TMTO) cryptanalysis proposed by Hellman can be applied for the various crypto-systems such as block ciphers, stream ciphers, and hash functions. In this paper, we propose a novel method to reduce memory size for storing TMTO tables. The starting points in a TMTO table can be substituted by the indices of n-bit samples from a sequence in a family of pseudo-random sequences with good cross-correlation, which results in the reduction of memory size for the starting points. By using this method, it is possible to reduce the memory size by the factor of 1/10 at the cost of the slightly increasing of operation time in the online phase. Because the memory is considered as more expensive resource than the time, the TMTO cryptanalysis will be more feasible for many real crypto systems.

• Physical Therapy Rehabilitation Science
• /
• v.10 no.3
• /
• pp.356-366
• /
• 2021

Objective: This study aimed to compare gait ability through gait evaluations in indoor and outdoor environments according to the general characteristics and walking ability of stroke patients. Design: Crossed-sectional study. Methods: The subjects of this study were 57 hospitalized stroke patients.The study subjects were asked to select an indoor environment and an outdoor environment in random order, and the Timed Up and Go Test (TUG), 10-Meter Walk Test (10MWT), Figure-Eight Walk Test (F8WT) and the Functional Gait Assessment (FGA) were used to assess each environment. Results: The TUG, 10MWT, F8WT time and number of steps, and FGA showed a significant decrease in gait ability in the outdoor environment compared to the indoor environment (p<0.05). Although the TUG, 10MWT, and the time required for the F8WT were statistically higher in the outdoor compared to the indoor environment at points 2, 3, and 4, but not 5 of the functional ambulatory category (FAC), significant increases in the number of steps of the F8WT were found in the outdoor compared to the indoor environment for only points 2 and 3 of the FAC (p<0.05). In the FAC 3 and 4, there was a statistically significant decrease in the outdoor compared to the indoor environment only in the FGA (p<0.05). Conclusions: Therefore, it has been shown that the gait ability of stroke patients is reduced in the outdoor environment compared to the gait ability in the indoor environment.

• Archives of Plastic Surgery
• /
• v.46 no.3
• /
• pp.248-254
• /
• 2019

Background No head to head comparison is available between surgical lip lifting and upper lip filler injections to decide which technique yields the best results in patients. Despite the growing popularity of upper lip augmentation, its effect on societal perceptions of attractiveness, successfulness and overall health in woman is unknown. Methods Blinded casual observers viewed three versions of independent images of 15 unique patient lower faces for a total of 45 images. Observers rated the attractiveness, perceived success, and perceived overall health for each patient image. Facial perception questions were answered on a visual analog scale from 0 to 100, where higher scores corresponded to more positive responses. Results Two hundred and seventeen random observers with an average age of 47 years (standard deviation, 15.9) rated the images. The majority of observers were females (n=183, 84%) of white race (n=174, 80%) and had at least some college education (n=202, 93%). The marginal mean score for perceived attractiveness from the natural condition was 1.5 points (95% confidence interval [CI], 0.9-2.18) higher than perceived attractiveness from the simulated upper lip filler injection condition, and 2.6 points higher (95% CI, 1.95-3.24) than the simulated upper lip lift condition. There was a moderate to strong correlation between the scores of the same observer. Conclusions Simulated upper lip augmentation is amenable to social perception analysis. Scores of the same observer for attractiveness, successfulness, and overall health are strongly correlated. Overall, the natural condition had the highest scores in all categories, followed by simulated upper lip filler, and lastly simulated upper lip lift.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.43 no.4
• /
• pp.67-75
• /
• 2020

This paper proposes a methodology for gantry route optimization in order to maximize the productivity of a odd-type surface mount device (SMD). A odd-type SMD is a machine that uses a gantry to mount electronic components on the placement point of a printed circuit board (PCB). The gantry needs a nozzle to move its electronic components. There is a suitability between the nozzle and the electronic component, and the mounting speed varies depending on the suitability. When it is difficult for the nozzle to adsorb electronic components, nozzle exchange is performed, and nozzle exchange takes a certain amount of time. The gantry route optimization problem is divided into the mounting order on PCB and the allocation of nozzles and electronic components to the gantry. Nozzle and electronic component allocation minimized the time incurred by nozzle exchange and nozzle-to-electronic component compatibility by using an mixed integer programming method. Sequence of mounting points on PCB minimizes travel time by using the branch-and-price method. Experimental data was made by randomly picking the location of the mounting point on a PCB of 800mm in width and 800mm in length. The number of mounting points is divided into 25, 50, 75, and 100, and experiments are conducted according to the number of types of electronic components, number of nozzle types, and suitability between nozzles and electronic components, respectively. Because the experimental data are random, the calculation time is not constant, but it is confirmed that the gantry route is found within a reasonable time.