• Journal of Institute of Control, Robotics and Systems
• /
• v.22 no.8
• /
• pp.579-584
• /
• 2016

When surgical instruments are tracked in an image-guided surgical navigation system, a stereo vision system with high accuracy is generally used, which is called optical tracker. However, this optical tracker has the disadvantage that a line-of-sight between the tracker and surgical instrument must be maintained. Therefore, to complement the disadvantage of optical tracking systems, an internal vision sensor is attached to a surgical instrument in this paper. Monitoring the target marker pattern attached on patient with this vision sensor, this surgical instrument is possible to be tracked even when the line-of-sight of the optical tracker is occluded. To verify the system's effectiveness, a series of basic experiments is carried out. Lastly, an integration experiment is conducted. The experimental results show that rotational error is bounded to max $1.32^{\circ}$ and mean $0.35^{\circ}$, and translation error is in max 1.72mm and mean 0.58mm. Finally, it is confirmed that the proposed tool tracking method using an internal vision sensor is useful and effective to overcome the occlusion problem of the optical tracker.

• Current Optics and Photonics
• /
• v.7 no.4
• /
• pp.387-397
• /
• 2023

Tooth surface shape error is an important parameter in gear accuracy evaluation. When tooth surface shape error is measured by laser interferometry, the gear interferogram is highly distorted and the gray level distribution is not uniform. Therefore, it is important for gear interferometry to extract the foreground region from the gear interference fringe image directly and accurately. This paper presents an approach for foreground extraction in gear interference images by leveraging the sinusoidal variation characteristics shown by the interference fringes. A gray level mask with an adaptive threshold is established to capture the relevant features, while a local variance evaluation function is employed to analyze the fluctuation state of the interference image and derive a repair mask. By combining these masks, the foreground region is directly extracted. Comparative evaluations using qualitative and quantitative assessment methods are performed to compare the proposed algorithm with both reference results and traditional approaches. The experimental findings reveal a remarkable degree of matching between the algorithm and the reference results. As a result, this method shows great potential for widespread application in the foreground extraction of gear interference images.

• Restorative Dentistry and Endodontics
• /
• v.19 no.2
• /
• pp.499-512
• /
• 1994

The purpose of this study was to evaluate the microleakage electrochemically using different retrograde filling materials, different root resection angle, and different cavity preparation instruments. 104 extracted single-rooted teeth were selected for this study. 100 teeth were used as experimental groups and four was used as controls. Anatomical crowns were resected, root canals were prepared, and the apical 2 mm of roots were removed. The experimental roots were randomly divided into five equal groups. Experimental groups : Group 1. no bevel, cavity preparation with ultrasonic instruments, amalgam filling Group 2. no bevel, cavity preparation with ultrasonic instruments, SuperEBA cement filling Group 3. no bevel, cavity preparation with ultrasonic instruments, desiccated ZOE filling Group 4. $45^{\circ}$ bevel, cavity preparation with ultrasonic instruments, amalgam filling Group 5. no bevel, cavity preparation with conventional bur, amalgam filling Microleakage was measured once a day for 30 days using electrochemical method and were analyzed statistically. The results were as follows : 1. The group with Super EBA cement filling showed the least marginal leakage from second to fourth day(p<0.05), there was no significant difference between the group with amalgam filling during eighth to eighteenth day(p>0.05), but after the nineteenth day here was a higher marginal leakage than the group with amalgam filling(p<0.05). 2. The group with desiccated ZOE filling demostrated that the highest marginal leakage, started on the eighth day(p<0.05). 3. The group using ultrasonic instrument showed lower marginal leakage than the group using bur until the nineteenth day(p<0.05), but there was no significant differnce with the group using bur after twentythird day(p>0.05). 4. The group without bevel showed lower marginal leakage than the group with bevel (p<0.05). 5. Whether bevel or nor had much more effect on marginal leakage than with cavity perparation instrument when the cavity was retrogrdefilled with amalgam(stepwise regression).

• Restorative Dentistry and Endodontics
• /
• v.7 no.1
• /
• pp.17-24
• /
• 1981

The purpose of this study is to compare the shape of the apical regions of root canals after instrumentation by various enlarging instruments. 120 extracted, single-rooted human teeth were seperated into 4 experimental groups. Each group provided 30 teeth for experimental use. Group 1 root canals instrumented by the hand-operated Reamer. Group 2 root canals instrumented by the hand-operated H-file. Group 3 root canals instrumented by the hand-operated K-file. Group 4 root canals instrumented by the automated Giromatic file. The results were as follows: 1. The degree of the roundness of the apical regions of root canal walls: 1) Hand-operated instruments were superior to the automated Giromatic file. 2) The Reamer was the most effective instrument among hand-operated instruments 3) There was little difference between the H-file and the K-file. 2. The degree of the smoothness of the apical regions of root canal walls: 1) Root canal walls instrumented by the hand-operated Reamer, H-file and, K-file were generally smooth, and there was little difference among them. 2) Root canal walls instrumented by the automated Giromatic file showed many irregular canal walls. 3. The existance of organic debris in the apical regions of root canals: All organic debris is not removed from root canals, and there was little difference between hand-operated instruments and the automated Giromatic instrument in removing organic debris.

• 한국HCI학회:학술대회논문집
• /
• 2008.02b
• /
• pp.405-410
• /
• 2008

There is always a rhythm in our language and speech. As soon as we speech out, even just simple words and voice we make are edited as various emotions and information. Through this process we succeed or fail in our communication, and it becomes a fun communication or a monotonous delivery. Even with the same music, impression of the play can be different according to each musician' s emotion and their understanding. We 'play' our language in the same way as that. However, I think, people are used to the variety, which is, in fact, the variation of a set format covered with hollow variety. People might have been living loosing or limiting their own creative way to express themselves by that hollow variety. SPACIAL POEM started from this point. This is a new type of 'real-time visual interaction' expressing our own creative narrative as real-time visual by playing a musical instrument which is an emotional human behavior. Producing many kinds of sound by playing musical instruments is the same behavior with which we express our emotions through. There are sensors on each hole on the surface of the musical instrument. When you play it, sensors recognize that you have covered the holes. All sensors are connected to a keyboard, which means your playing behavior becomes a typing action on the keyboard. And I programmed the visual of your words to spread out in a virtual 3D space when you play the musical instrument. The behavior when you blow the instrument, to make sounds, changes into the energy that makes you walk ahead continuously in a virtual space. I used a microphone sensor for this. After all by playing musical instrument, we get back the emotion we forgot so far, and my voice is expressed with my own visual language in virtual space.

• Journal of Ecology and Environment
• /
• v.38 no.3
• /
• pp.293-305
• /
• 2015

In order to understand the mechanisms of conversion between different algal dominance, an experiment was performed in a greenhouse from 22 June to 10 July 2011. The experiment included a treatment group subjected to three instances of nutrient enrichment and a control with no nutrient enrichment. The initial water was dominated by Ankistrodesmus of Chlorophyta. The average water temperature at 08:30 h and 14:00 h during the experiment was $31.6^{\circ}C$ and $34.6^{\circ}C$, respectively. The results showed that the total nitrogen (TN), total phosphorus (TP), dissolved total nitrogen (DTN), dissolved total phosphorus (DTP), and soluble reactive phosphorus (SRP) concentrations in the treatment were significantly higher than in the control (P < 0.05). However, the TN/TP and DTN/DTP in the control was higher than in the treatment (P < 0.05). The dominant algae in the control did not change during the experiment, while the dominant algae in the treatment switched to Planktothrix of Cyanophyta on day 9. The chlorophyll a (Chl-a), wet weight of all algae, wet weight of Cyanophyta, and percentage of Cyanophyta in the control were all significantly lower than in the treatment (P < 0.05). Amounts of zooplankton, especially rotifers, were present at the end of the experimental period. The density of rotifers between the control and treatment was not significantly different (P > 0.05), while the copepod density in the treatment was higher than in the control (P < 0.05). We conclude that green algae dominance quickly switches to cyanobacteria dominance after nutrient enrichment in a greenhouse with elevated temperature.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.15 no.4
• /
• pp.154-160
• /
• 2007

The experimental system, developed in this research, is a teaching material that trains and practices automobile electric circuit in technical high school. This system consists of a textbook, 15 kinds of instruments and 62 kinds of 'Flash' animations. Textbook includes automobile electric circuits and experimental process. Instruments have 23 kinds of drills. Its is composed of electrical relays, motors, switches, light bulbs, electrical lines and power unit so on. 'Flash' animation displays an electrical current flow on circuits actually. Both Dacum method and ISD skill have been conducted to analysis job and design syllabus. The experimental system have been implemented on technical high school class to evaluate its objectivity and effect. It is expected that this system can contribute to studying of car service.

• Journal of the Korean Society of School Health
• /
• v.19 no.2
• /
• pp.89-104
• /
• 2006

Purpose： This study was to develop and verify the effects of drug misuse and abuse preventive program for middle school students. Methods：This research was a quasi experimental study under the nonequivalent control group with pretest-post test design which tried to protect children from the detrimental effect of drugs and develop a drug abuse prevention program for middle school students. Data was collected from October 10th to 21th, 2005. Subject consisted of 145 middle school students in Kyeonggi, experimental group-72, control group-73. Dick & Carey's(1996) educational system was applied, based on documents and materials online related to drug abuse in order to develop drug abuse prevention program. It's composed of 4 parts, 45 minute each. The evaluation instrument testing for the knowledge about drugs was a criterion of referenced test items modeled by Dick & Carey. The instrument for attitudes about drugs was modeled by Kim, Soyaja. A pre-test was taken on the knowledge and attitudes to drugs. The experimental students were given four sessions of drug abuse prevention education. A post-test similar to the pre-test questionnaire was given in 1 week, 4 weeks following the last session. Collected data was analyzed by using SAS 9.1 program. Results：Followings are the summarized result of study 1. The experimental group, that attended the drug abuse prevention program will have more knowledgable about drugs than the control group (F=27.31, p<.0001). 2. The experimental group, that attended the drug abuse prevention program displayed greater negativism attitude than the control group (F=0.58, p=0.4477). Conclusion：The results conclude that drug abuse prevention programs increase the knowledge of middle school students but doesn't change their attitude toward drugs. Therefore we need to offer them more systematic education to increase their knowledge so it will also improve their attitudes as well.

• Asian Oncology Nursing
• /
• v.2 no.1
• /
• pp.61-71
• /
• 2002

Gastric Carcinoma is very plentiful and significant disease in Korean community. The reason is that Gastric Carcinoma is not a simply finding disease with unclear symptoms for early detection. Early detection and early medical treatment of a cancer patient is an important instrument of reducing the mortility rate. The purpose of this study is to identify the effect of audiovisual information with videotape infulencing on knowledge and attitude of early detection of gastric carcinoma. The research design was a non-equivalent control group, pre-post test. The subjects of this study were 52 members of D-taxi drivers which was located in Pusan. The subjects were twenty six experimental group and twenty six control group. The experimental group was collected from January 15, 1999 to January 26, 1999. The control group was collected from the research was 28 minutes video program which was turning out the form of documentary on the based practical experience. And also the experimental tool was used measurung instrument which measured a dependent, variable throughout the consulatation of an percentage, average, standard deviation, ${\chi}^2-test$ and t-test using spss/pc program. The result of this research were as follows : 1)" The experimental group which was offered the video program, should be higher in knowledge of early detection of the gastric carcinoma than the control group" was supported. (t= -7.754, p=.000) 2) "The experimental group which was offered the video program, should be higher in attitude of the early detection of the gastric carcinoma than the control group" was supported. (t=-4.321, p=.000) Therefore, in conclusion, this study that the audiovisual information with videotape influencing on knowledge and attitude of early detection of gastric carcionma was very representational experience throughout the video of documentary form on the based practical experience was much effected the change of the knowledge and the attitude regarding to the early detection of the gastric carcinoma was verified.

• Journal of Korean Public Health Nursing
• /
• v.15 no.1
• /
• pp.96-110
• /
• 2001

The purpose of this study was to examine the effect of emotional and informational support intervention on role stress and depression of primary family caregivers caring stroke patients and to develop an effective nursing intervention method for them. This study selected the quasi-experiment, based on pre-test and post-test design of non-equivalent control group as a method of study. This study was conducted with 69 primary family caregivers caring stroke patients hospitalized in K and D hospitals in Daegu from August 20 to October 25, 2000. Out of them, 34 were placed in the experimental group, and 35 in the control group. The emotional and informational intervention program was divided into two aspects-emotional support and informational support- and executed three times, using prepared instruments and a guidebook. The intervention program consisted of the 1st intervention for one or one-half hour, the 2nd intervention for 30 minutes in two or three days after the 1st intervention. and the 3rd intervention for 30minutes in another two or three days after the 2nd intervention. Pre-test was carried out just before the 1st intervention, and the post-test was carried out right after the 3rd intervention, in order to collect data. The measuring instrument of role stress used was one that was modified to the role stress instrument of Yang Young-hee(1992) and the stress instrument of Choi Eun-sook (1992). The reliability was Cronbach's $\alpha=.8271$. The measuring instrument of depression used was one that was developed by Beck(1967) and standardized by Han Heung-moo et al(1986). The reliability was Cronbach's $\alpha=.8693$. Data were analyzed with percentage, mean, standard deviation, $x^2-test$, t-test and Paired t-test by using SPSS 9.0 program. The results of this study are summarized as follows: 1. Role stress score of the experimental group was revealed to be significantly lower than that of the control group 2. Depression score of the experimental group was revealed to be significantly lower than that of the control group Accordingly, the emotional and informational support intervention can be a way to reduce role stress and depression of primary family caregivers caring stroke patients.