• Journal of Korean Society of Forest Science
• /
• v.84 no.4
• /
• pp.465-478
• /
• 1995

The objective of this study was to investigate the impacts of large-scale timber harvesting on the environment of a mature hardwood forest. To achieve the objective, the effects of harvesting on forest environmental factors were analyzed quantitatively using the field data measured in the study sites of Seoul National University Research Forests [(Mt.) Paekunsan] for two years(1993-1994) following timber harvesting. The field data include information on vegetation, soil mesofauna, physicochemical characteristics of soil, surface water runoff, water quality in the stream, and hillslope erosion. For comparison, field data for each environmental factor were collected in forest areas disturbed by logging and undisturbed, separately. The results of this study were as follows : The diversity of vegetational species increased in the harvested sites. However, the similarity index value of species between harvested and non-harvested sites was close to each other. Soil bulk density and soil hardness were increased after timber harvesting, respectively. The level of organic matter, total-N, avail $P_2O_5$, CEC($K^+$, $Na^+$, $Ca^{{+}{+}}$, $Mg^{{+}{+}}$) in the harvested area were found decreased. While the population of Colembola spp., and Acari spp. among soil mesofauna in harvested sites increased by two to seven times compared to those of non-harvested sites during the first year, the rates of increment decreased in the second year. However, those members of soil mesofauna in harvested sites were still higher than those of non-harvested sites in the second year. The results of statistical analysis using the stepwise regression method indicated that the diversity of soil mesofauna were significantly affected by soil moisture, soil bulk density, $Mg^{{+}{+}}$, CEC, and soil temperature at soil depth of 5(0~10)cm in the order of importance. The amount of surface water runoff on harvested sites was larger than that of non-harvested sites by 28% in the first year and 24.5% in the second year after timber harvesting. The level of BOD, COD, and pH in the stream water on the harvested sites reached at the level of the domestic use for drinking in the first and second year after timber harvesting. Such heavy metals as Cd, Pb, Cu, and organic P were not found. Moreover, the level of eight factors of domestic use for drinking water designated by the Ministry of Health and Welfare of Korea were within the level of the first class in the quality of drinking water standard. The study also showed that the amount of hillslope erosion in harvested sites was 4.77 ton/ha/yr in the first year after timber harvesting. In the second year, the amount decreased rapidly to 1.0 ton/ha/yr. The impact of logging on hillslope erosion in the harvested sites was larger than that in non-harvested sites by seven times in the first year and two times in the second year. The above results indicate that the large-scale timber harvesting cause significant changes in the environmental factors. However, the results are based on only two-year field observation. We should take more field observation and analyses to increase understandings on the impacts of timber harvesting on environmental changes. With the understandings, we might be able to improve the technology of timber harvesting operations to reduce the environmental impacts of large-scale timber harvesting.

• Journal of Intelligence and Information Systems
• /
• v.26 no.1
• /
• pp.75-95
• /
• 2020

With the growth of social networks, various forms of SNS have emerged. Based on various motivations for use such as interactivity, information exchange, and entertainment, SNS users are also on the fast-growing trend. Facebook is the main SNS channel, and companies have started using Facebook pages as a public relations channel. To this end, in the early stages of operation, companies began to secure a number of fans, and as a result, the number of corporate Facebook fans has recently increased to as many as millions. from a corporate perspective, Facebook is attracting attention because it makes it easier for you to meet the customers you want. Facebook provides an efficient advertising platform based on the numerous data it has. Advertising targeting can be conducted using their demographic characteristics, behavior, or contact information. It is optimized for advertisements that can expose information to a desired target, so that results can be obtained more effectively. it rethink and communicate corporate brand image to customers through contents. The study was conducted through Facebook advertising data, and could be of great help to business people working in the online advertising industry. For this reason, the independent variables used in the research were selected based on the characteristics of the content that the actual business is concerned with. Recently, the company's Facebook page operation goal is to go beyond securing the number of fan pages, branding to promote its brand, and further aiming to communicate with major customers. the main figures for this assessment are Facebook's 'OK', 'Attachment', 'Share', and 'Number of Click' which are the dependent variables of this study. in order to measure the outcome of the target, the consumer's response is set as a key measurable key performance indicator (KPI), and a strategy is set and executed to achieve this. Here, KPI uses Facebook's ad numbers 'reach', 'exposure', 'like', 'share', 'comment', 'clicks', and 'CPC' depending on the situation. in order to achieve the corresponding figures, the consideration of content production must be prior, and in this study, the independent variables were organized by dividing into three considerations for content production into three. The effects of content material, content structure, and message styles on Facebook's user behavior were analyzed using regression analysis. Content materials are related to the content's difficulty, company relevance, and daily involvement. According to existing research, it was very important how the content would attract users' interest. Content could be divided into informative content and interesting content. Informational content is content related to the brand, and information exchange with users is important. Interesting content is defined as posts that are not related to brands related to interesting movies or anecdotes. Based on this, this study started with the assumption that the difficulty, company relevance, and daily involvement have an effect on the dependent variable. In addition, previous studies have found that content types affect Facebook user activity. I think it depends on the combination of photos and text used in the content. Based on this study, the actual photos were used and the hashtag and independent variables were also examined. Finally, we focused on the advertising message. In the previous studies, the effect of advertising messages on users was different depending on whether they were narrative or non-narrative, and furthermore, the influence on message intimacy was different. In this study, we conducted research on the behavior that Facebook users' behavior would be different depending on the language and formality. For dependent variables, 'OK' and 'Full Click Count' are set by every user's action on the content. In this study, we defined each independent variable in the existing study literature and analyzed the effect on the dependent variable, and found that 'good' factors such as 'self association', 'actual use', and 'hidden' are important. Could. Material difficulties', 'actual participation' and 'large scale * difficulties'. In addition, variables such as 'Self Connect', 'Actual Engagement' and 'Sexual Sexual Attention' have been shown to have a significant impact on 'Full Click'. It is expected that through research results, it is possible to contribute to the operation and production strategy of company Facebook operators and content creators by presenting a content strategy optimized for the purpose of the content. In this study, we defined each independent variable in the existing research literature and analyzed its effect on the dependent variable, and we could see that factors on 'good' were significant such as 'self-association', 'reality use', 'concernal material difficulty', 'real-life involvement' and 'massive*difficulty'. In addition, variables such as 'self-connection', 'real-life involvement' and 'formative*attention' were shown to have significant effects for 'full-click'. Through the research results, it is expected that by presenting an optimized content strategy for content purposes, it can contribute to the operation and production strategy of corporate Facebook operators and content producers.

• Tuberculosis and Respiratory Diseases
• /
• v.49 no.3
• /
• pp.310-322
• /
• 2000

Background : Phospholipase C(PLC) plays an important role in cellular signal transduction and is thought to be critical in cellular growth, differentiation and transformation of certain malignancies. Two second messengers produced from the enzymatic action of PLC are diacylglycerol (DAG) and inositol 1, 4, 5-trisphosphate (IP3). These two second messengers are important in down stream signal activation of protein kinase C and intracellular calcium elevation. In addition, functional domains of the PLC isozymes, such as Src homology 2 (SH2) domain, Src homology 3 (SH3) domain, and pleckstrin homology (PH) domain play crucial roles in protein translocation, lipid membrane modificailon and intracellular memrane trafficking which occur during various mitogenic processes. We have previously reported the presence of PLC-${\gamma}1$, ${\gamma}2$, ${\beta}1$, ${\beta}3$, and ${\delta}1$ isozymes in normal human lung tissue and tyrosine-kinase-independent activation of phospholipase C-${\gamma}$ isozymes by tau protein and AHNAK. We had also found that the expression of AHNAK protein was markedly increased in various mstologic types of lung can∞r tissues as compared to the normallungs. However, the report concerning expression of various PLC isozymes in lung canærs and other lung diseases is lacking. Therefore, in this study we examined the expression of PLC isozymes in the paired surgical specimens taken from lung cancer patients. Methods : Surgically resected lung cancer tissue samples taken from thirty seven patients and their paired normal control lungs from the same patients, The expression of various PLC isozymes were studied. Western blot analysis of the tissue extracts for the PLC isozymes and immunohistochemistry was performed on typical samples for localization of the isozyme. Results : In 16 of 18 squamous cell carcinomas, the expression of PLC-${\gamma}1$ was increased. PLC-${\gamma}1$ was also found to be increased in all of 15 adenocarcinoma patients. In most of the non-small cell lung cancer tissues we had examined, expression of PLC-${\delta}1$ was decreased. However, the expression of PLC-${\delta}1$ was markedly increased in 3 adenocarcinomas and 3 squamous carcinomas. Although the numbers were small, in all 4 cases of small cell lung cancer tissues, the expression of PLC-${\delta}1$ was nearly absent. Conclusion : We found increased expression of PLC-${\gamma}1$ isozyme in lung cancer tissues. Results of this study, taken together with our earlier findings of AHNAK protein-a putative PLD-${\gamma}$, activator-over-expression, and the changes observed in PLC-${\delta}1$ in primary human lung cancers may provide a possible insight into the derranged calcium-inositol signaling pathways leading to the lung malignancies.

• Journal of Periodontal and Implant Science
• /
• v.37 no.sup2
• /
• pp.427-445
• /
• 2007

To improve osseointegration at the boneto-implant interface, several studies have been carried out to modify titanium surface. Variations in surface texture or microtopography may affect the cellular response to an implant. Osteoblast-like cells attach more readily to a rougher titanium surface, and synthesis of extracellular matrix and subsequent mineralization were found to be enhanced on rough or porous coated titanium. However, regarding the effect of roughened surface by physical and mechanical methods, most studies carried out on the reactions of cells to micrometric topography, little work has been performed on the reaction of cells to nanotopography. The purpose of this study was to examme the response of osteoblast-like cell cultured on blasted surfaces and alkali treated surfaces, and to evaluate the influence of surface texture or submicro-scaled surface topography on the cell attachment, cell proliferation and the gene expression of osteoblastic phenotype using ROS 17/2.8 cell lines. In scanning electron micrographs, the blasted, alkali treated and machined surfaces demonstrated microscopic differences in the surface topography. The specimens of alkali treatment had a submicro-scaled porous sur-face with pore size about 200 nm. The blasted surfaces showed irregularities in morphology with small(<10 ${\mu}m$) depression and indentation among flatter-appearing areas of various sizes. Based on profilometry, the blasted surfaces was significantly rougher than the machined and the alkali treated surfaces (p$TiO_2$) were observed on alkali treated surfaces, whereas not observed on machined and blasted surfaces. The attachment morphology of cells according to time was observed by the scanning electron microscope. After 1 hour incubation, the cells were in the process of adhesion and spreading on the prepared surfaces. After 3 hours, the cells on all prepared surfaces were further spreaded and flattened, however on the blasted and alkali treated surfaces, the cells exhibited slightly irregular shapes and some gaps or spaces were seen. After 24 hours incubation, most cells of the all groups had a flattened and polygonal shape, but the cells were more spreaded on the machined surfaces than the blasted and alkali treated surfaces. The MTT assay indicated the increase on machined, alkali treated and blasted surfaces according to time, and the alkali treated and blasted surfaces showed significantly increased in optical density comparing with machined surfaces at 1 day (p<0.01). Gene expression study showed that mRNA expression level of ${\alpha}\;1(I)$ collagen, alkaline phosphatase and osteopontin of the osteoblast-like cells showed a tendency to be higher on blasted and alkali treated surfaces than on the machined surfaces, although no siginificant difference in the mRNA expression level of ${\alpha}\;1(I)$ collagen, alkaline phosphatase and osteopontin was observed among all groups. In conclusion, we suggest that submicroscaled surfaces on osteoblast-like cell response do not over-ride the one of the surface with micro-scaled topography produced by blasting method, although the microscaled and submicro-scaled surfaces can accelerate osteogenic cell attachment and function compared with the machined surfaces.

• Journal of Nutrition and Health
• /
• v.44 no.5
• /
• pp.428-442
• /
• 2011

This study investigated the actual status of constipation. In total, 978 female students in Korea participated. We identified the relationship among constipation and life style, clothing patterns, housing patterns, dietary habits, and dietary intake in a constipation symptom group and a normal group. The actual constipation rate based on the Rome II criteria was 27.0% (n = 264). Body weight (p < 0.05) and body mass index (p < 0.05) in the constipation group were significantly higher than those in the normal group. The incidence of functional bowel disease and irritable bowel syndrome in the constipation group were significantly higher than those in the normal group. The discomfort of wearing underwear was significantly higher in the constipation group than that in the normal group. The constipation group revealed a significantly higher rate of irregular dietary habits than those in the normal group. The dietary diversity score of the normal group was 4.22 (p < 0.05), which was significantly higher than that of constipation group (4.12). No significant difference in life style factors was observed. It is necessary for university female students to correct their dietary habits, maintain food intake of three times per day, and select diverse foods. Furthermore, it is necessary for university female students to wear comfortable clothing to lessen symptoms and improve constipation rates.

• Korean Journal of Cleft Lip And Palate
• /
• v.9 no.2
• /
• pp.85-92
• /
• 2006

Korean Cleft Lip and Palate Association (KCLPA) was founded in 1996. The first overseas charity operation was in Karachi, Pakistan, 2002 and our association has visited fourteen times in six countries for the free cleft surgery: Pakistan, Egypt, Kenya, Morocco, Jordan and Vietnam. The cumulated number of operated patients reaches to 280. Before our association, many Korean oral and maxillofacial surgeons have performed charity operations individually since 1964. It was started from Vietnam but the activity is now carried on in Africa, middle-east Asia, south-east Asia, China, and Korea as an official team. LG electronics, a Korean company helped to propagate our team's activity to middle-east Asia to Africa. This paper is a report concerning about the results of our association's charity activities especially in Kenya, east Africa. We provided free cleft surgery for 30 patients in 2004 and 27 patients in 2005, in Nairobi. As the blood test for HIV of the cleft patients was not allowed before and during surgery, our surgeons and nurses were cautious about every movement during the surgeries. Thus the operation time for each patient was longer than any other time. The attitude of the local hospital and the doctors seemed to be accustomed to this situation. They helped us in case of needle injuries. Safety of medical staff and patients is more important than the number of the patients operated in charity operation. This belief should be approached being parallel and multidisciplinary as an international cooperation, focusing on international funding for medical support and continuous education for local doctors who are willing to devote to their people.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.12 no.2
• /
• pp.73-83
• /
• 1983

This experiment was conducted to study effects of different sources of protein, and of the different combination ratios of the two protein supplemented or unsupplemented with methionine on the growth and body metabolism of the growing male rats. Casein and isolated soyprotein (ISP) were combined at different ratios of 100:0, 80:20, 50:50, 20:80 and 0:100 to supply the constant levels of dietary energy and protein of 3,600kcal/kg and 20%, respectively. Each combination was supplemented with either 0 or 0.3% methionine. Results obtained in these experiments were summarized as follows: The body weight and weight gain in the ISP diet were the lowest, but were increased with the increase of ratios of casein to ISP. The body weight gain in the ISP diet supplemented with methionine was similar to that in the combination diets of casein and ISP. The combination diets of casein and ISP supplemented with methionine had the higher weight gain than the casein diet. The food intake in the casein diet was the highest, and was increased with the increase of ratios of casein to ISP, and was lowered with methionine supplementation. The food intake in the ISP diet was the lowest and was not increased with methionine supplementation to the ISP diet. The food efficiency ratio of the combination diets of casein and ISP was improved compared to those of either the casein or the ISP diets. The food efficiency ratio was improved in the diet of either casein of ISP supplemented with methionine, but was not improved in the combination diets of casein and ISP with methionine supplementation. The gross energy intake had direct relation with the food intake of rats and the relation was increased either in the casein diet of with the increase of the ratios of casein to ISP. The energy efficiency and protein efficiency ratios were improved in the diet of either casein of ISP by the supplementation of methionine, and the effect of methionine supplementation of the energy efficiency and protein efficiency atio was increased with the increase of the ratios of ISP to casein. The nitrogen intake and urinary nitrogen excretion of the casein diet were the highest and those of the ISP diet were the lowest. They were increased with the increase of ratios of casein to ISP. The nitrogen balance and retention were not significantly among the treatments. The gross energy intake and fecal and urinary energy were the highest in the casein diet but the digestible and metabolizable energy and the digestibility and metabolizability of energy were not significantly different among the treatments. The body fat content of rats was increased by supplementation of methionine but the body protein content was decreased (r=-0.65, p<0.01). The body fat content of rats was negatively correlated with body moisture content (r=-0.83, p<0.01). The liver weight was highly correlated with the carcass weight (r=0.79, p<0.01), and was increased by the methionine supplementation and by the increase of the ratios of casein to ISP.

• Tuberculosis and Respiratory Diseases
• /
• v.45 no.5
• /
• pp.962-974
• /
• 1998

Background: Alteration of p53 tumor suppressor genes is most frequently identified in human neoplasms, including lung carcinoma. It is well known that bcl-2 oncoprotein protects cells from apoptosis. Recent studies have demonstrated that bcl-2 expression is associated with favorable prognosis for patients with non-small cell lung carcinoma. However, the precise biologic role of bcl-2 in the development of these tumors is still obscure. p53 and bcl-2 have important regulatory influence in the apoptotic pathway and thus their relationship is of interest in tumorigenesis, especially lung cancer. Purpose: The author investigated to know the prognostic significance of the expression of p53 and bcl-2 in radically resected non-small cell lung cancer. Method: 84 cases of formalin-fixed paraffin-embedded blocks from resected primary non-small cell lung cancer from 1980 to 1994 at Hanyang University Hospital were available for both clinical follow-up and immunohistochemical staining using monoclonal antibodies for p53 and bcl-2. Results : The histologic classification of the tumor was based on WHO criteria., and the specimens included 45 squamous cell carcinomas(53.6%), 28 adeonocarcinomas(33.3%) and 11 large cell carcinomas(13.1 %). p53 immunoreactivity was noted in 47 cases of 84 cases(56.0%). bcl-2 immunoreactivity was noted in 15 cases of 84 cases(17.9%). The mean survival duration was $64.23{\pm}10.73$ months in bcl-2 positive group and $35.28{\pm}4$. 39 months in bcl-2 negative group. The bcl-2 expression was significantly correlated with survival in radically resected non-small cell lung cancer patients(p=0.03). The mean survival duration was $34.71{\pm}6.12$ months in p53 positive group and $45.35{\pm}6.30$ months in p53 negative group(p=0.21). The p53 expression was not predictive for survival. There was no correlation between combination of the different status of p53 and bcl-2 expression in our study. Conclusions : The interaction and the regulation of new biologic markers, such as those involved in the apoptotic pathway, are complex. bcl-2 overexpression is a good prognostic factor in non-small cell lung cancer and p53 expression is not significantly associated with the prognostic factor in non-small cell lung cancer.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.23 no.4
• /
• pp.153-178
• /
• 2018

Most operational uses of wind speed data require measurements at, or estimates generated for, the reference height of 10 m above mean sea level (AMSL). On the Ieodo Ocean Research Station (IORS), wind speed is measured by instruments installed on the lighthouse tower of the roof deck at 42.3 m AMSL. This preliminary study indicates how these data can best be converted into synthetic 10 m wind speed data for operational uses via the Korea Hydrographic and Oceanographic Agency (KHOA) website. We tested three well-known conventional empirical neutral wind profile formulas (a power law (PL); a drag coefficient based logarithmic law (DCLL); and a roughness height based logarithmic law (RHLL)), and compared their results to those generated using a well-known, highly tested and validated logarithmic model (LMS) with a stability function (${\psi}_{\nu}$), to assess the potential use of each method for accurately synthesizing reference level wind speeds. From these experiments, we conclude that the reliable LMS technique and the RHLL technique are both useful for generating reference wind speed data from IORS observations, since these methods produced very similar results: comparisons between the RHLL and the LMS results showed relatively small bias values ($-0.001m\;s^{-1}$) and Root Mean Square Deviations (RMSD, $0.122m\;s^{-1}$). We also compared the synthetic wind speed data generated using each of the four neutral wind profile formulas under examination with Advanced SCATterometer (ASCAT) data. Comparisons revealed that the 'LMS without ${\psi}_{\nu}^{\prime}$ produced the best results, with only $0.191m\;s^{-1}$ of bias and $1.111m\;s^{-1}$ of RMSD. As well as comparing these four different approaches, we also explored potential refinements that could be applied within or through each approach. Firstly, we tested the effect of tidal variations in sea level height on wind speed calculations, through comparison of results generated with and without the adjustment of sea level heights for tidal effects. Tidal adjustment of the sea levels used in reference wind speed calculations resulted in remarkably small bias (<$0.0001m\;s^{-1}$) and RMSD (<$0.012m\;s^{-1}$) values when compared to calculations performed without adjustment, indicating that this tidal effect can be ignored for the purposes of IORS reference wind speed estimates. We also estimated surface roughness heights ($z_0$) based on RHLL and LMS calculations in order to explore the best parameterization of this factor, with results leading to our recommendation of a new $z_0$ parameterization derived from observed wind speed data. Lastly, we suggest the necessity of including a suitable, experimentally derived, surface drag coefficient and $z_0$ formulas within conventional wind profile formulas for situations characterized by strong wind (${\geq}33m\;s^{-1}$) conditions, since without this inclusion the wind adjustment approaches used in this study are only optimal for wind speeds ${\leq}25m\;s^{-1}$.

• The Journal of Korean Philosophical History
• /
• no.23
• /
• pp.99-128
• /
• 2008

This research analyzes some Korean historical figures and presents the core values of their leaderships so that we can bring up the theory of leadership which would be compatible with the current circumstances around Korea. Through this work, we expected that we would not only find out typical examples among historical leaders but also reaffirm our identities in our history. As a result of the research, it was possible to classify some figures in history into several patterns and discover their archetypal qualities. Those qualities were 'transform(實事)', 'challenge(決死)', 'energize(風流)', 'create(創案)', and 'envision(開新)' respectively. Among the qualities, this research concentrated on the quality of 'challenge', exclusively 'death-defying spirit'. This spirit is the one with which historical leaders could sacrifice their lives for their great causes. This research selected twelve figures as incarnations of death-defying spirit, who are Gyebaek(階伯), Ganggamchan(姜邯贊), Euljimundeok(乙支文德), Choeyoung(崔瑩),ChungMongju(鄭夢周), Seongsammun (成三問), Yisunsin(李舜臣), Gwakjaewoo(郭再祐), Choeikhyeon(崔益鉉), Anjunggeun(安重根), Yunbonggil(尹奉吉), Yijun(李儁). Through analyzing their core values and abilities and categorizing some historical cases into four spheres such as a private sphere, relations sphere, a community sphere, and a society sphere, we came to find a certain element in common among those figures. It was that they eventually took the lead by showing the goal and the ideal to their people at all times. Moreover, their goals were always not only obvious but also unwavering. In the second chapter, I described the core value in a private sphere, so called '志靑靑'. It implies that a leader should set his ultimate goal and then try to attain it with an unyielding will. Obvious self-confidence and unfailing self-creed are core values in a private sphere. In the third chapter, I described the core value in a relative sphere, the relationship between one and others. It is '守信結義'. It indicates that a leader should win confidence from others by discharging his duties in the relation with others. Confidence is the highest leveled affection to others. Thus, mutual reliance should be based on truthful sincerity and affection toward others. Stubbornness and strictness are needed not to be prompted by pity simultaneously. In the fourth chapter, I described the core value in a community sphere. It is '丹心合力'. For this value, what are required to a leader are both his community spirit and his loyalty to one's community. Moreover, the strong sense of responsibility and the attitude of taking an initiative among others are also required. Thus, it can be said that the great power to conduct the community is so called fine teamwork. What's more, the attitude of the leader can exert a great influence on his community. In the fifth chapter, I described the core value of death defying spirit in the society sphere. This value might be more definite and explicit than other ones described above. A leader should prepare willingly for one's death to fulfill his great duties. 'What to do' is more important for a leader than 'how to do'. That is to say, a leader should always do righteous things. Efficiency is nothing but one of his interests. A leader must be the one who behaves himself always according to righteousness. Unless a leader's behaviors are based on righteousness, it is absolutely impossible that a leader exerts his leadership toward people very efficiently. Thus, it can be said that a true leader is the one not only who is of morality and but also who tries to fulfill his duties.