• Journal of Korean Society of Forest Science
• /
• v.81 no.1
• /
• pp.1-10
• /
• 1992

This study was conducted to explain the characters of the structure of biomass production in the thrifty-mature Quercus mongolica stands and investigate the relationships between the leaf weight or leaf area and the sapwood area in the bole. Also we intended to identify the allocation ratio of stem, branches, and leaves or heartwood, sapwood and bark in trees and the characters of productive structure of stem and leaf biomass by the tree height. The results obtained were as follows : 1. The allocation ratio of biomass based on dry weight was 70-84% in stem, 11-25% in branches, and 3-6% in leaves. 2. In the bole, the ratios of composition of heartwood, sapwood, and bark were showed 37-43%, 38-46%, and 16-19%, respectively. 3. The volume of sapmood was exceeded more than that of heartwood in dominant and intermediate trees, while it was reversely appeared in suppressed trees. 4. The weight and area of leases significantly correlated with the sectional area of sapwood in bole (r>0.9. 1% significant level). 5. The ratio of leaf area($m^2$) to sapwood areal($cm^2$), k varied 0.35 to 2.05. 6. The basal diameter and the cross sectional area of a branch significantly correlated with the leaf weight r>0.9. 1% significant level. 7. The leaf weight in a tree is showed a normal distribution curve and the accumulative volume of bole is showed a tapering type.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.27 no.2
• /
• pp.17-24
• /
• 2023

A post-processing technique for the measurement signal of a solenoid-type sensor is introduced. The solenoid-type sensor nondestructively evaluates an external tendon of prestressed concrete using the total flux leakage (TFL) method. The TFL solenoid sensor consists of primary and secondary coils. AC electricity, with the shape of a sinusoidal function, is input in the primary coil. The signal proportional to the differential of the input is induced in the secondary coil. Because the amplitude of the induced signal is proportional to the cross-sectional area of the tendon, sectional loss of the tendon caused by ruptures or corrosion can be identified by the induced signal. Therefore, it is important to extract amplitude information from the measurement signal of the TFL sensor. Previously, the amplitude was extracted using local maxima, which is the simplest way to obtain amplitude information. However, because the sampling rate is dramatically decreased by amplitude extraction using the local maxima, the previous method places many restrictions on the direction of TFL sensor development, such as applying additional signal processing and/or artificial intelligence. Meanwhile, the proposed method uses amplitude demodulation to obtain the signal amplitude from the TFL sensor, and the sampling rate of the amplitude information is same to the raw TFL sensor data. The proposed method using amplitude demodulation provides ample freedom for development by eliminating restrictions on the first coil input frequency of the TFL sensor and the speed of applying the sensor to external tension. It also maintains a high measurement sampling rate, providing advantages for utilizing additional signal processing or artificial intelligence. The proposed method was validated through experiments, and the advantages were verified through comparison with the previous method. For example, in this study the amplitudes extracted by amplitude demodulation provided a sampling rate 100 times greater than those of the previous method. There may be differences depending on the given situation and specific equipment settings; however, in most cases, extracting amplitude information using amplitude demodulation yields more satisfactory results than previous methods.

• The Journal of Korean Society for Radiation Therapy
• /
• v.12 no.1
• /
• pp.69-84
• /
• 2000

It has been reported that the cancer patient's quality of life is influenced by the perceived health state, self-esteem, health locus of control, social support, whether there is a pain or not, the stage of a disease, the period of a disease, etc, and however, there has been scarcely the research into the fact at home whose cultural and social backgrounds are entire1y different from those of American and European Countries. Accordingly, the author of this thesis performed this study. considering that it is necessary to know the relations between the health locus of control which make it possible to predict the object's behavior related to health and to make plans to induce the object or patient into sound behavior and the quality of life which is closely related to the cancer patient's health, emotion, society, economy, etc. on the whole. This study, a cross-sectional one, includes 135 subjects of $in{\cdot}out$ patients registered at Y University Hospital whose age are more than 20 years, From these patients, data were collected for two weeks through the questionnaire which content concerns about the quality of life and the health locus of control. All the collected data were processed and analyzed through Student's t-test, ANOVA, and the calculation of Pearson Correlation Coefficient, using the SAS program 1. It appeared that the disposition of health locus of control was mostly inclined to the disposition of powerful other health locus of control($28.37{\pm}4.24$), then inclined to internal health locus of control($27.03{\pm}4.17$), and next to chance health locus of control($19.71{\pm}4.97$) By the way. the disposition of powerful other health locus of control appeared a tittle bit higher than internal health locus of control 2. The degree of the quality of life appeared to be 137.54 points in the average of total points and 3.11 in the average evaluation mark. It appeared that the quality of life was most significantly influenced by a factor of 'relations with neighbors' and least significantly influenced by factors of physical conditions and functions. 3. It appeared that the relation between the disposition of health locus of control and the quality of life has nothing to do with the relation between internal health locus of control and the quality of life(r=.1446, P>.05) and also with the relation between the disposition of powerful other health locus of control(r=.0385, P>.05). In conclusion, in the study it has been found out that there is no correlation between the health locus of control and the quality of life, and however it is sound to induce the cancer patient to internal health locus of control. Therefore, it is necessary that under the special circumstances, the cancer patient's behavior should be predicted, thereby inducing the patient to the sound change of his or her behavior. Also in order that the patient enjoys his or her life satisfactorily while living, It is deemed that some kind of multilateral meditation in health and treatment is necessary so that the patient can feel the relief of pain, better health, etc.

• Journal of Digital Convergence
• /
• v.12 no.4
• /
• pp.367-378
• /
• 2014

The purpose of this study was to explore the factors related to internet addiction in college student of Korea. Methods: From November 19, 2012 until December 14, 2012, 300 college students from one of the universities located at K city were surveyed. This study is a cross-sectional survey of college students in K city, and data was collected through self-report questionnaires. Data was analyzed by Fisher's exact test, independent t-test to identify different according to addiction group, and logistic regression analysis in order to factors related to on health behavior, sexual behavior and mental health of among college students. According to results, factors related to risk of addiction were lower frequency of exercise (p<0.05), no eat breakfast for 2 day (p<0.05), porno magazine/porno video contact pornography (p<0.05), subjective happiness index (p<0.05), and suicidal Ideation (p<0.05). This study suggest that exercise, regular diet, important of reproductive health, subjective happiness index and Suicidal Ideation are associated with internet addiction in College student. It is necessary to develop some preventive programs for those of internet addiction.

• Korean Journal of Materials Research
• /
• v.4 no.8
• /
• pp.855-860
• /
• 1994

Ta-silicide films in polycide structure were prepared by rapid thermal annealing of sputtered Ta film on poly-Si and doped poly-Si. Effects of phosphorus on Ta-silicide formation were investigated. Independent of the ion dose($1 \times 10^{13}\to 5 \times 10^{15}$/ions/$\textrm{cm}^2$), Ta-silicide phases were formed at $800^{\circ}C$ and stabilized above $1000^{\circ}C$. From the result of XRD at $800^{\circ}C$ and $900^{\circ}C$, however, it was indicated that the more the doping concentration the weaker the intensity of Ta-silicide phases. Furthermore, the observation of SEM revealed that the increase of the doping concentration retarded silicidation. As the temperature increased, the dopant effect was weakened gradually and almost disappeared at $1000^{\circ}C$. Therefore the variation of the ion dose from ($1 \times 10^{13}\to 5 \times 10^{15}$/ions/$\textrm{cm}^2$) did not greatly affect the formation of Ta-silicide at high temperatures but retarded slightly the silicidation at low temperatures.

• Journal of Korea Water Resources Association
• /
• v.42 no.12
• /
• pp.1113-1124
• /
• 2009

The abandoned channel restoration is one of methods to enhance the environmental function and ecological habitat as well as the functions of water-utilization and flood control. The channel-forming or dominant discharge must be evaluated and defined to design the cross-sectional and plane geometries of the stable and equilibrium channel for the abandoned channel restoration project. In general, bankfull discharge, specified recurrence interval discharge, and effective discharge have been used to decide the channel-forming discharge. In this study, bankfull discharge, specified recurrence interval discharge, and effective discharge were calculated and compared for the abandoned channel restoration site of Cheongmi Stream and their relations to historical bed changes were analyzed. The bankfull discharge, 488 $m^3/s$, of the abandoned channel restoration site of Cheongmi Stream was calculated using HEC-RAS data and ranged between 1.5-year and 2-year recurrence discharges. Also, the effective discharge evaluated with the sediment rating curve and mean daily discharge data is greater than the bankfull discharge. According to the survey data of 1994 and 2008, the bed elevation of the study reach was decreased over time. It is indicated that the channel bed is changing to the stable condition to allow the effective discharge.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.25 no.6
• /
• pp.1061-1068
• /
• 2011

Moxibustion is a treatment method for cold and pain in Korean medicine. But the systematic study of moxibustion were very few. This study was aimed to survey and evaluate moxibustion study in Korean medicine. We search the moxibustion study in journals related Korean medicine and http://oasis.kiom.re.kr. The period of the study from first issue to August, 2010. The search word were moxibustion, moxa in keyword and moxibustion treatment in title. We totally search 334 articles. But 175 articles were excluded because this study were not exactly moxibustion study, so we included and analyzed 159 articles. The study of moxibustion were 159 articles. Literature review were 35 articles, systematic review 8, heat experiment 10, in vivo or vitro 28 and survey investigation 3. Clinical articles of moxibustion related to Korean medical journals were 76. Before and after study were 31 articles, case report 20, cohort study 7, cross-sectional study 2, nonrandomized study 6, quasi randomized study 1, randomized clinical trials 9. This results showed that moxibustion study were smaller than acupuncture or herb and concentrated to pain and cold syndrome. We need further larger and diverse study of moxibustion.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.08a
• /
• pp.222-222
• /
• 2012

Metal oxide gas sensors based on semiconductor type have attracted a great deal of attention due to their low cost, flexible production and simple usability. However, most works have been focused on n-type oxides, while the characteristics of p-type oxide gas sensors have been barely studied. An investigation on p-type oxides is very important in that the use of them makes possible the novel sensors such as p-n diode and tandem devices. Monoclinic cupric oxide (CuO) is p-type semiconductor with narrow band gap (~1.2 eV). This is composed of abundant, nontoxic elements on earth, and thus low-cost, environment-friendly devices can be realized. However, gas sensing properties of neat CuO were rarely explored and the mechanism still remains unclear. In this work, the neat CuO layers with highly ordered mesoporous structures were prepared by a template-free, one-pot solution-based method using novel ink solutions, formulated with copper formate tetrahydrate, hexylamine and ethyl cellulose. The shear viscosity of the formulated solutions was 5.79 Pa s at a shear rate of 1 s-1. The solutions were coated on SiO2/Si substrates by spin-coating (ink) and calcined for 1 h at the temperature of $200{\sim}600^{\circ}C$ in air. The surface and cross-sectional morphologies of the formed CuO layers were observed by a focused ion beam scanning electron microscopy (FIB-SEM) and porosity was determined by image analysis using simple computer-programming. XRD analysis showed phase evolutions of the layers, depending on the calcination temperature, and thermal decompositions of the neat precursor and the formulated ink were investigated by TGA and DSC. As a result, the formation of the porous structures was attributed to the vaporization of ethyl cellulose contained in the solutions. Mesoporous CuO, formed with the ink solution, consisted of grains and pores with nano-meter size. All of them were strongly dependent on calcination temperature. Sensing properties toward H2 and C2H5OH gases were examined as a function of operating temperature. High and fast responses toward H2 and C2H5OH gases were discussed in terms of crystallinity, nonstoichiometry and morphological factors such as porosity, grain size and surface-to-volume ratio. To our knowledge, the responses toward H2 and C2H5OH gases of these CuO gas sensors are comparable to previously reported values.

• Safety and Health at Work
• /
• v.4 no.1
• /
• pp.27-36
• /
• 2013

Objectives: Mental health has been shown to be linked with certain underlying physiological mechanisms. The objective of this cross sectional study was to investigate the relationship between depressive symptoms and brachial artery reactivity (BAR) in an understudied population: police officers. Methods: Participants were 351 police officers who were clinically examined in the Buffalo Cardio-Metabolic Police Stress (BCOPS) study. BAR was performed using standard B-Mode ultrasound procedures. Depressive symptoms were measured using the Center for Epidemiological Studies Depression (CES-D) scale. Mean values of the difference between the baseline and maximum diameters of the brachial artery were determined across three categories of CES-D score using the analysis of variance and the analysis of covariance. p-values for linear trends were obtained from linear regression models. Results: The mean age (${\pm}$ standard deviation) of all officers was $40.9{\pm}7.2$ years. Women had a slightly higher mean CES-D score than men ($8.9{\pm}8.9$ vs. $7.4{\pm}6.4$) and a slightly higher percentage increase of BAR than men (6.90 vs. 5.26%). Smoking status significantly modified the associations between depressive symptoms and BAR. Among current smokers, mean absolute values of BAR significantly decreased as depressive symptoms increased after adjustment for age, gender, race/ethnicity, hypertension, and diabetes; the multivariate-adjusted p-values were 0.033 (absolute) and 0.040 (%). Associations between depressive symptoms and BAR were not statistically significant among former smokers or never smokers. Conclusion: Depressive symptoms were inversely associated with BAR among police officers who were current smokers and together may be considered a risk factor for cardiovascular disease among police officers. Further prospective research is warranted.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.15 no.2
• /
• pp.23-34
• /
• 2012

As the quality of life grows, the role of cultural facilities in urban areas is becoming more important. However, due to various reasons, the location of these facilities shows the geographical imbalance between urban regions. Even though provision of road network can improve this kind of urban problem, in many countries, the provision of urban infrastructure plays a role which is magnifies the cultural gap between regions and socio-economic classes. The findings of this study are as follows. First of all, the inequality of accessibility to cultural facilities is shown over the period. Cross-sectional data shows that the higher the income of a region, the higher the accessibility index(AI) of the zone to cultural facilities at any time. Next, the provision of road network contributes the improvement of AI of high income region. Finally the provision of new facilities has a tendency that these kind of facilities are located to make AI of high income zone better. It means that the decision making by city government intensifies the geographical inequality. This result would be very useful in the decision making process for determining the number and the location of cultural facilities and other similar urban infrastructure as well. Also it will be helpful for the selection of optimal location which considered not only physical distances but also social equalities.