• Journal of Institute of Control, Robotics and Systems
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• v.20 no.12
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• pp.1225-1230
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• 2014

This paper investigates the group average-consensus and group formation-consensus problems for first-order multi-agent systems. The control protocol for group consensus is designed by considering the positive adjacency elements. Since each intra-group Laplacian matrix cannot be satisfied with the in-degree balance because of the positive adjacency elements between groups, we decompose the Laplacian matrix into an intra-group Laplacian matrix and an inter-group Laplacian matrix. Moreover, average matrices are used in the control protocol to analyze the stability of multi-agent systems with a fixed and undirected communication topology. Using the graph theory and the Lyapunov functional, stability analysis is performed for group average-consensus and group formation-consensus, respectively. Finally, some simulation results are presented to validate the effectiveness of the proposed control protocol for group consensus.

• Asia pacific journal of information systems
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• v.9 no.1
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• pp.143-163
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• 1999

This study investigates the effect of group size on group performance, here the quality of group decision, Four effects are proposed and tested in a field experimental setting : (1) the relationship between the group size and the distribution of individual's problem-solving ability ; (2) the change of the group decision quality as group size increases ; (3) the relationship between the group decision quality and the quality of the best/worst member as group size increases ; (4) the relationship between the group decision quality and the average quality of individuals in the group as group size increases. Data showed that contrary to the exiting results, group decision quality was not improved with the group size. Rather, it showed a little tendency that group decision quality was worsened with the group size. Data also showed that consensus-oriented group decision making process produced the compromised output. Thus, group decision quality was not better than the average group members'. The opinion of the best member was not accepted. The implications of the findings are discussed for the development of a Korean GSS.

• Journal of Korean Academy of Nursing
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• v.17 no.1
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• pp.9-23
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• 1987

Nursing service, as the largest user of labor resources, has become concerned about appropriate allocation of staffing resources. Therefore, this project was designed to measure quantitatively the direct nursing care provided to patients and to develop a new patient classification system based on the direct nursing care activities. The initial step in the development of the classification instrument was to identify the content of direct nursing activities. The frequency with which these activities were carried out, the total time spent in carrying them out and the average time for one performance of each of the nursing activities was calculated. The next step was to select the items for the classification instrument taking into account these direct nursing activities. A list of 40 items was prepared. These items were then classified into 8 major categories: personal hygiene, moving ＆ exercise, nutrition & elimination, observation, medication, treatment, collecting specimens and other care activities for severity ill patients. Each item was assigned a value unit based on the average time required by the nursing staff to complete the specific item. The third step was to determine the practicality of the items and value units, so an attempt was made to establish content validity for these items and units by obtaing a consensus from 8 head nurses, representing eight different departments. The 4th step was to conducted a pilot study to establish the score range for the classification boundaries. For this purpose an instrument was designed using the list of items and value units and a prepared classification criteria as a guideline to validate the patient classification. A judgment group consisting of 52 supervisory nurses and head nurses were asked to select the proper patient to fit each classification criteria and to fill out the instrument for each patient. The total value unit and the frequency for each classification group was calculated. According to the frequency distribution, the score range for the classification group was determined as follows : 0~15 for groupI, 16~30 for group II, 31~50 for group III, and above 51 for group IV. Finally a patient classification form was developed.

• Journal of Chest Surgery
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• v.49 no.5
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• pp.361-365
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• 2016

Background: Sternal fractures are relatively rare, and caused mainly by blunt anterior chest wall trauma. In most cases, sternal fractures are treated conservatively. However, if the patient exhibits problematic symptoms such as intractable chest wall pain or bony crepitus due to sternal instability, surgical correction is indicated. But no consensus exists regarding the most appropriate surgical method. We analyzed the results of surgical fixation in cases of sternal fracture in order to identify which surgical method led to the best outcomes. Methods: We retrospectively reviewed the medical records of patients with sternal fractures from December 2008 to December 2011, and found 19 patients who underwent open reduction and internal fixation of the sternum with a longitudinal plate (L-group) or a T-shaped plate (T-group). We investigated patients' characteristics, clinical details regarding each case of chest trauma, the presence of other associated injuries, the type of open reduction and fixation, whether a combined operation was performed, and postoperative complications. Results: Of the 19 patients, 10 patients (52.6%) were male, and their average age was 56.8 years (range, 32 to 82 years). Seven patients (36.8%) had isolated sternal fractures, while 12 (63.2%) had other associated injuries. Seven patients (36.8%) were in the L-group and 12 patients (63.2%) were in the T-group. Three patients in the L-group (42.9%) showed a loosening of the fixation. In all patients in the T-group, the fracture exhibited stable alignment. Conclusion: Open reduction and internal fixation with a T-shaped plate in sternal fractures is a safer and more efficient treatment method than treatment with a longitudinal plate, especially in patients with a severely displaced sternum or anterior flail chest, than a longitudinal plate.

• Journal of Periodontal and Implant Science
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• v.42 no.3
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• pp.88-94
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• 2012

Purpose: The use of appropriate instruments to clean surfaces with minimal change, is critical for the successful maintenance of a dental implant. However, there is no consensus about the type and methodology for such instruments. The aim of this study was to characterize changes in the roughness of titanium surfaces treated by various scaling instruments. Methods: Thirty-seven identical disks (5 mm in diameter) were investigated in this study. The specimens were divided into eight groups according to the types of instrumentation and the angle of application. Ultrasonic scaling systems were applied on a titanium disk to simulate standard clinical conditions. The equipment included a piezoelectric ultrasonic scaler with a newly developed metallic tip (NS group), a piezoelectric ultrasonic scaler with a conventional tip (CS group), a piezoelectric root planer ultrasonic scaler with a conventional tip (PR group), and a plastic hand curette (PH group). In addition, the sites treated using piezoelectric ultrasonic scaler systems were divided two sub-groups: 15 and 45 degrees. The treated titanium surfaces were observed by scanning electron microscopy (SEM), and the average surface roughness (Ra) and mean roughness profile depth (Rz) were measured with a profilometer. Results: SEM no significant changes in the titanium surfaces in the NS group, regardless of the angle of application. The PH group also showed no marked changes to the titanium surface, although some smoothening was observed. All CS and PR sites lost their original texture and showed irregular surfaces in SEM analysis. The profilometer analysis demonstrated that the roughness values (Ra and Rz) of the titanium surfaces increased in all, except the PH and NS groups, which showed roughness decreases relative to the untreated control group. The Ra value differed significantly between the NS and PR groups (P<0.05). Conclusions: The results of this study indicated that changes in or damage to titanium surfaces might be more affected by the hardness of the scaler tip than by the application method. Within the limitations of this study, the newly developed metallic scaler tip might be especially suitable for peri-implant surface decontamination, due to its limited effects on the titanium surface.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.3 s.309
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• pp.78-84
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• 2006

Our study aimed at quantitative assessment of a cleft palate nose deformity condition by analyzing the following parameters gathered from a photographic image of a cleft palate patient: (1) angle difference between two nostril axes, (2) center of the nostril and distance between two centers, (3) overlapped area of two nostrils, and (4) the overlapped area ratio of the two nostrils. A regression equation of doctor's grades was obtained using the eight parameters. Three plastic surgeons gave us the glades for the each photographic image by to increments with maximum grade of 100. The average reproducibility of the grades given by the three plastic surgeons and the three laymen using the developed program was $10.8{\pm}4.6%\;and\;7.4{\pm}1.8%$, respectively. Kappa values representing the degree of consensus of the plastic surgeons and the three laymen were 0.43 and 0.83, respectively. Correlation coefficient of the grades evaluated by the surgeons and obtained by the regression equation was 0.642 and that of the grades by the surgeons and by the neural network was 0.798. In conclusion, the developed neural network model provided us better reproducibility, much better consensus, and better correlation than doctor's subjective evaluation in addition to objectiveness and easy application.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.3
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• pp.331-339
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• 2008

The genetic structure and diversity of 15 Chinese indigenous chicken breeds was investigated using 29 microsatellite markers. The total number of birds examined was 542, on average 36 birds per breed. A total of 277 alleles (mean number 9.55 alleles per locus, ranging from 2 to 25) was observed. All populations showed high levels of heterozygosity with the lowest estimate of 0.440 for the Gushi chickens, and the highest one of 0.644 observed for Wannan Three-yellow chickens. The global heterozygote deficit across all populations (FIT) amounted to 0.180 (p<0.001). About 16% of the total genetic variability originated from differences between breeds, with all loci contributing significantly to this differentiation. An unrooted consensus tree was constructed using the Neighbour-Joining method and pair-wise distances based on marker estimated kinships. Two main groups were found. The heavy-body type populations grouped together in one cluster while the light-body type populations formed the second cluster. The STRUCTURE software was used to assess genetic clustering of these chicken breeds. Similar to the phylogenetic analysis, the heavy-body type and light-body type populations separated first. Clustering analysis provided an accurate representation of the current genetic relations among the breeds. Remarkably similar breed rankings were obtained with all methods.

• Archives of Plastic Surgery
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• v.33 no.2
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• pp.193-197
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• 2006

Pulmonary thromboembolism is often clinically silent and difficult to diagnose, and can be fatal to patients with belated treatment. This complication is seen in patients who underwent TRAM breast reconstruction. Multiple factors are involved in this disease such as the presence of malignancy itself, major surgery and therapy-related interventions. TRAM surgery is a lengthy procedure involving mastectomy, flap surgery and abdominoplasty. The purpose of this study is to evaluate the incidence and the correlation between presurgical risk factors(BMI and age) of symptomatic pulmonary thromboembolism after TRAM surgery and the incidence. From July 2001 to March 2005 a total of 384 pedicled TRAM reconstruction of breast was performed in 382 patients at Asan Medical Center. The average of Body mass index was $21.9kg/m^2$ and mean age of the patients was 37.9 years old. We diagnosed symptomatic pulmonary thromboembolism using ventilation/perfusion lung scan and pulmonary embolism computed tomography. Incidence of in-hospital symptomatic pulmonary thromboembolism was 1.3%. BMI and age showed no significant statistical relationship to pulmonary thromboembolism. But the incidence of symptomatic pulmonary thromboembolism in obese patients (BMI > 25) was 3.75%. According to the guideline of the 7th American College of Chest Physicians Consensus Conference on Antithrombotic and Thrombolytic Therapy, the incidence of 3.75% was classified as high risk group. The prevention of pulmonary thromboembolism should be considered in cases of obese patients with low molecular weight heparin(BMI > 25).

• Food Science and Industry
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• v.51 no.3
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• pp.209-217
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• 2018

Delphi technique is widely used to develop consensus on group opinion. It is important to identify the strategic technologies and evaluate technology level for the establishment of national R&D policy to upgrade technology level. The aim of this article was to reflect on Food Safety technology level by using Delphi methodology. And, competitiveness of patents and journal articles is evaluated for Korea, USA, Japan, China and EU. As a result, USA is the most competitive country for all technology categories. The average technology level of Korea was 79.5% of world-top coungry and average technological gap was 6.1 years. Korea is grouped in middle-lower class for overall food safety technology level. However, there are some variances among the level of technologies. As a result of this study, food safety research management needs to expand R&D investment and training of food safety specialist. The results of this research can be utilized to establish a road map for transportation R&D and plans.

• Sleep Medicine and Psychophysiology
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• v.26 no.2
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• pp.86-103
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• 2019

Objectives: The objective of this study was to develop evidence- and consensus-based clinical safety usage guidelines for sedative hypnotics using the Delphi technique. Methods: A group of 15 sleep experts from Korean Academy of Sleep Medicine were chosen for this study comprising a three-round web-based Delphi survey. The first round survey was composed of 39 questions to identify problems with sedative hypnotics usage in Korean clinical practice and the result roughly outlined what should be included in the guidelines. The second round survey was composed of 21 questions to collect specific opinions of experts on clinically important issues in prescribing sedative hypnotics, and its result provided the basis for the guidelines. A third round survey aimed to evaluate the reliability and validity of the established guidelines. Results: In the third round, all 17 items showed a median of 4 or more, with an average of 4.12 and a standard deviation of 0.32. Thus we present safety usage guidelines with 13 propositions for prescription, maintenance, and withdrawal of sedative hypnotics. Conclusion: The safety usage guidelines on sedative hypnotics developed from this study could lead to safe and effective prescription of hypnotics in clinical practice, especially for the non-experts in sleep medicine. Furthermore, the guidelines will help to improve the quality of insomnia treatment by contributing to the establishment of a safe regime for sedative hypnotics without excessive use of drugs.