• Journal of Biomedical Engineering Research
• /
• v.31 no.3
• /
• pp.217-226
• /
• 2010

The lower limb orthosis with a pneumatic rubber actuator, which is intended for the assistance and the enhancement of muscular activities of lower limbs was developed in this study. Compared to other knee extension assistive devices being developed by other researchers, our device is designed especially for the elderly people and intended only for slight assistance so that the subjects can keep their muscular strength. For the effectiveness of system, muscular activities of major muscles in lower limbs during sit-to-stand (STS) and squat motion were measured and analyzed. Subjects were performed the STS and squat motion with and without lower limb orthosis. We made comparison muscular activities between with and without lower limb orthosis. Lower limb orthosis was controlled using muscular stiffness force feedback that is controlled by muscular activities of the measured muscle from force sensor. For analysis of muscular activities, electromyography of the subjects was measured during STS and squat motion, and these were measured using MP 150(BIOPAC Systems, Inc.). Muscles of interest were rectus femoris(RF), vastus lateralis(VL), vastus medialis(VM) and vastus intermedius(VI) muscles in lower limbs of the right side. A biodex dynamometer was used to measure the maximal concentric isokinetic strength of the knee extensors of wearing and not wearing orthosis on right side. The test were performed using the concentric isokinetic mode of test with the velocity set at 60°/s for muscles around the knee joints. The experimental result showed that muscular activities in lower limbs wearing orthosis using muscular stiffness force of a vastus medialis muscle was reduced and knee extension torque of an knee joint wearing lower limb orthosis was increased. With this, we confirmed the effectiveness of the developed lower limb orthosis.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.23 no.3
• /
• pp.445-457
• /
• 2013

This paper is about the study to build a quantitative methodology to assess cyber threats and vulnerabilities on control systems. The SCADA system in power industry is one of the most representative and biggest control systems. The SCADA system was originally a local system but it has been extended to wide area as both ICT and power system technologies evolve. Smart Grid is a concept to integrate energy and IT systems, and therefore the existing cyber threats might be infectious to the power system in the integration process. Power system is operated on a real time basis and this could make the power system more vulnerable to the cyber threats. It is a unique characteristic of power systems different from ICT systems. For example, availability is the most critical factor while confidentiality is the one from the CIA triad of IT security. In this context, it is needed to reflect the different characteristics to assess cyber security risks in power systems. Generally, the risk(R) is defined as the multiplication of threat(T), vulnerability(V), and asset(A). This formula is also used for the quantification of the risk, and a conceptual methodology is proposed for the objective in this study.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.17 no.1
• /
• pp.7-15
• /
• 2004

The ferroelectric SBT thin films as a material of capacitors for non-volatile FRAMs have some problems that its remanent polarization value is relatively low and the crystallization temperature is quite high abovc 80$0^{\circ}C$. Therefore, in this paper, SBTN solution with S $r_{0.9}$B $i_{2.1}$T $a_{1.8}$N $b_{0.2}$$O_{9}$ composition was synthesized by sol-gel method. Sr(O $C_2$ $H_{5}$)$_2$, Bi(TMHD)$_3$, Ta(O $C_2$ $H_{5}$)$_{5}$and Nb(O $C_2$ $H_{5}$)$_{5}$ were used as precursors, which were dissolved in 2-methoxyethanol. SBTN thin films with 200 nm thickness were deposited on Pt/Ti $O_2$/ $SiO_2$/Si substrates by spin-coating. UV-irradiation in a power of 200 W for 10 min and rapid thermal annealing in a 5-Torr-oxygen ambient at 76$0^{\circ}C$ for 60 sec were used to promote crystallization. The films were well crystallized and fine-grained after annealing at $650^{\circ}C$ in oxygen ambient. The electrical characteristics of 2Pr=11.94 $\mu$C/$\textrm{cm}^2$, Ps＋/Pr＋=0.54 at the applied voltage of 5 V were obtained for a 200-nm-thick SBTN films. This results show that 2Pr values of the UV irradiated and rapid thermal annealed SBTN thin films at the applied voltage of 5 V were about 57% higher than those of no additional processed SBTN thin films. thin films.lms.s.s.

• Resources Recycling
• /
• v.9 no.1
• /
• pp.52-62
• /
• 2000

In order to maximize the recycling of converter slag to the more valuable fields, such as high quality aggregates for construction, cement industry and flux for ion making. It will be very important to control the compositions and properties of converter slag to suit the purpose of utilizastion. In this study, converter slag (STELCO, CANADA) was mixed with 5%~30% $SiO_2$and 7% carbon, and then reduced at $1650^{\circ}C$. After the reduction was completed, the reformed slags were cooled to room temperature in the furnace. All of the slags were then characterized using SEM-EDX, XRD and chemical analysis. Also the compressive strengths and densities of the reformed slags were measured to compare with natural aggregates. XRD analysis shows that th phases of reformed slags are changed from bredigite+merwinite mixed phases of 10% $SiO_2$added reduction to akermanite phases of 20% and 30% $SiO_2$ added reduction. But the SEM-EDX analysis revealed that the phase distribution of the reformed slags was changed very sensitively and complicately depends on the change of slag compositions. And also the properties of reformed slags are changed very much depend on the phase distribution. About one third of Cadmium and on fifth of Vanadium are remained in reduction reformed converter slag. Another heavy metal elements such as cobalt, zinc, lead are removed up to more than 90-95% of original slag. The compressive strength and density of 25% $SiO_2$ added and reformed slag is very near to natural granite. This is superior more than 10% to Thyssen's $SiO_2$ added and oxidized converter slag aggregates.

• Journal of the Korean Magnetics Society
• /
• v.18 no.5
• /
• pp.174-179
• /
• 2008

The measurement dissolution sensor system using GMR-SV device with magnetic sensitivity of 0.8 %/Oe and Mg-film thick of 200 nm and Mg-foil thick of 50 mm was fabricated and characterized. During the water dissolving process of Mg-film and Mg-foil, the subtle variation of magnetic field by the decrease of current in solenoid was detected by the GMR-SV sensor. The variations of Mg bubble number and ORP as a function of time for three different kinds of edible, tap, and distilled water, are measured and compared. A After 45 min, the speed of fast dissolving Mg was shown the order of edible > tap > DI water. The variation of output magnetoresistance as a function of dissolved time of Mg-film and Mg-foil for edible water, which is composed of mineral content of $0.8{\sim}5.4\;mg/l$ was investigated. The response times for the dissolution in edible water were 5 min and 20 min, respectively. From the measurement of dissolving time and speed for Mg-film and Mg-foil using GMR-SV device, the mineral Mg sensor system in edible water can be possible to develop.

• The Journal of Advanced Prosthodontics
• /
• v.3 no.4
• /
• pp.216-220
• /
• 2011

PURPOSE. Heat of composite polymerization (HP) indicates setting efficacy and temperature increase of composite in clinical procedures. The purpose of this in vitro experimental study was to evaluate the effects of 5 temperatures on HP of two new composites. MATERIALS AND METHODS. From each material (Core Max II [CM] and King Dental [KD]), 5 groups of 5 specimens each were prepared and their total HPs (J/gr) were measured and recorded, at one of the constant temperatures $0^{\circ}C$, $15^{\circ}C$, $23^{\circ}C$, $37^{\circ}C$ and $60^{\circ}C$ ($2{\times}5{\times}5$ specimens) using a differential scanning calorimetry (DSC) analyzer. The data were analyzed using a two-way ANOVA, a Tukey's test, an independent-samples ttest, and a linear regression analysis (${\alpha}=0.05$). RESULTS. No polymerization reactions occurred at $0^{\circ}C$; then this temperature was excluded from statistical analyses. The mean HP of the remaining 20 KD specimens was $20.5{\pm}14.9$ J/gr, while it was $40.7{\pm}12.9$ J/gr for CM. The independent-samples t-test showed that there were significant differences between the HP of the two materials at the temperatures $15^{\circ}C$ (P=.0001), $23^{\circ}C$ (P=.0163), $37^{\circ}C$ (P=.0039), and $60^{\circ}C$ (P=.0106). Linear regression analysis showed statistically significant correlations between environment temperatures and HP of CM ($R^2=0.777$). CONCLUSION. Using CM is advantageous over conventional composite because of its better polymerization capacity. However due to its high HP, further studies should assess its temperature increase in vivo. Preheating KD is recommended. Refrigerating composites can negatively affect their polymerization potential.

• Korean Journal of Occupational Health Nursing
• /
• v.9 no.1
• /
• pp.39-48
• /
• 2000

Hyperlipemia is the most leading risk factor of cardiovascular disease which is the main cause of death in Korea. However, there is a tendency to neglect the prevention and treatment since it has no specific symptoms. It has been reported that the level of serum-lipid can be lowered by the improvement of eating habits. Therefore, it is highly likely that the development of programs on the improvement of eating habits through behavioral theory is required to the community nursing practice. The theory of planned behavior, which assumes that human behaviors are determined by one's intention to carry out the behavior, can be characterized by the point that behaviors are not only individual factors but also social behaviors relating to subjective norms. It is widely recognized that this theory has a high predictability on health behavior due to it's simplicity clearness, and measurability as well as high quality of being general. Thus, the theory of planned behavior could be useful in developing a model of a health promotion program to the change of behaviors of the risk group of cardiovascular disease. Consequently, based on the theory of planned behavior, the purpose of this study is to develop an intention promotion program of the diet, and then to testify the effects. The sample of this study consisted of 26 industrial workers who had proved hyperlipemia from a medical examination in 1996 (experimental group 13, control group 13). The intention promotion program, which includes education, monitoring, pressure, counselling on the level of individuals, families and organizations, was conducted for 10 weeks The purpose of this program was to promoting intention of the diet through changes of the prerequisite factors of intention such as behavioral belief, outcome evaluation, normative belief and control belief. When it came to data analysis, the ${\chi}^2$-test and Fisher's Exact test were used to compare the general characteristics between the experimental and the control group, an independent t-test for the other variables. ANOVA was used to the test hypothesis, and the Pearson correlation test for variable's correlation. The results of this study can be summarized as follows ; 1) There was a significant increase in the intention(F=18.51, p=.00) of diet in the experimental group. 2) Diets(F=32.51, p=.001) in the experimental group were better carried out than in the control group. 5) There was a moderate correlation between the intention of diet and performance (r=.587. p=.003). From the results, it can be concluded that the intention promotion program is very effective, leading to the change of health promotion behavior. Above all, it is really valuable that the intention promotion program in this study regards health promotion behavior as a social behavior and that intervention was done on the level of family and organization. Consequently, when performing a health promotion program, social approach elevating the intention should go hand in hand in order to make the program effective.

• Journal of Preventive Medicine and Public Health
• /
• v.24 no.2 s.34
• /
• pp.171-180
• /
• 1991

Productivity analysis of physician is one of essential factors for the optimal health manpower planning. Among 690 physicians operating clinic and registered on the Kyeongsangnamdo Medical Association, 623 physicians were studied with a structural questionaire from April 1 to May 31, 1990. This study covers the general characteristics and productivity of physicians and attempts to find relevant determinants of their productivity through stepwise multiple regression analysis based on collected data. The mar results were as follows. First, physicians were more prevalent $35{\sim}44$ group (30.2%) in age, male (95.8%) in sex, specialist (76.5%) in specialization,'city (78.0%) in geographical location. Age group of 35-54 and specialist were mere prevalent in cities than in counties, while age group of 25-44 and 55 over and general practitioner in counties (p<0.001). Second, daily outpatients load of all physician were 77.1 persons on average. Age group of $35{\sim}44$ had the most outpatient load (90.3 persons) among all age group, $6{\sim}10$ years group (94.2 persons) in years of duration of practice, 11 hours per day group (83.4 persons) in working hours per day. Specialists had more outpatient load (82.6 persons) than general practitioners (61.1 persons) and physicians in cities had more (80.2 persons) than physicians in counties (66.3 persons). Daily average outpatient load of physicians were significantly different by their age, speciality, number of assistants and years of practice (p<0.001) and working location (p<0.05), but not significantly different by working hours per day of physician (p>0.1). Third, the productivity of physicians operating clinic were significantly affected by the three factors-number of assistants of physician, age of physician and duration of practice at the current clinic. Age of physician had negative regression coefficient.

• Journal of Korean Public Health Nursing
• /
• v.16 no.2
• /
• pp.454-468
• /
• 2002

Historically, women's health needs have been viewed primarily as reproductive, and all other health needs have been dealth with without considering their responses to disease and treatment(Strickland & Giger, 1994). It has mostly been through the efforts of women's group, especially health care team, that more recognition has been given to the overall health of women worker in recent years. The purpose of this study was to examine the depression, self-esteem and health practice in order to identify health care strategies to improve health promotion among women workers in small workplace. The consisted of 94 women workers who work at small manufacturing industry. The data were collected from January to February, 2002. The instruments for this study was Rogenburgs self-esteem scale, Zung s depression self-reporting scale and Breslow & Enstrom s health habits scale. The analysis of data were performed with frequency, percentage, t-test, ANOVA. $\chi^2$ test, pearson correlation and multiple regression using SPSS Win 10.1 program. 1. The average depression score was 1.87 which is relatively low and the average self-esteem score was 2.75 which is relatively moderate. The total mean score for health practice was 4. 10(range 0-7) which is relatively high moderately. 2. Health practice had not a statistically significant correlation with depression and self-esteem, but the depression had a statistically significant correlation with self-esteem(r=-.401, p=.000). 3. There was not a significant difference In depression, self-esteem and health practice according to the general characteristics 4. There was a significant difference in sub category of health practice according to the status of living with family and status of marriage. As far as the health practice of women workers living with family practiced better health than women workers no living with family concerning breakfast(p=.03) and as far as the health practice of women workers no living with family practiced better health than women workers living with family concerning sleeping time(p=.04). There was a significant difference in breakfast(p=.04), smoking(p=.00), and BMI(p=.05) according to the status of marriage. 5. The major factor was age and explained for $7\%$ of health practice. The repeated study should be carried out to figure out the health practice and its related factors of female workers at small manufacturing industry.

• Korean Journal of Adult Nursing
• /
• v.12 no.2
• /
• pp.245-255
• /
• 2000

The purpose of this study is to compare the physical health, anxiety and depression of the Dan-Jeon Breathing trained group with those of a non-trained group and to analyze the relationship between the training period of Dan-Jeon Breathing method and physical health, anxiety, and depression. The number of people in the Dan-Jeon Breathing trained group over 3 months was 149 and in the non-trained group 142. Data were collected from August to October 1999. As tools, 35 physical symptom questions were chosen from The Cornell Medical Index modified by Nam(1965) and from the Symptom Checklist-90-Revision(SCL-90-R) by Kim(1984); 10 questions on anxiety and 13 questions on depression were used in the study. The statistics of the study were gathered by using SPSS Window; the analysis was made by applying $X^2$-test, t-test, Pearson correlation, ANOVA and Scheffe tests. The results were as follows. 1. The Dan-Jeon Breathing trained group had lower physical symptom score and showed less anxiety and depression than the non-trained group, which supported the 1st, 2nd, 3rd hypotheses. 2. The longer the training period of Dan-Jeon Breathing, the lower the physical symptom score, which supports the 4th hypothesis, but the 5th and, 6th hypotheses were not supported because anxiety and depression did not get lower as the training period of Dan-Jeon Breathing got longer. 3. The physical symptom score, anxiety and depression that were made by the general characteristics of Dan-Jeon Breathing trained group were analyzed. As a result, the physical symptom score of women was greater than that of men. Physical symptoms score and the rate of anxiety and depression were different by education levels. The degree of anxiety was different by age. Those who have a religion have a higher physical symtoms score than people who have no religion. There was no difference in physical health score, anxiety and depression according to marital status, economic status and occupations. The results suggest that the physical and mental health status of Dan-Jeon Breathing trained group is better than that of the non-trained group. Physical symptoms scores gets lower as the training period of Dan-Jeon Breathing gets longer which results in the improvement of physical health status.