• The Korean Journal of Ecology
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• v.28 no.5
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• pp.327-333
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• 2005

For the first time in Korea, plant size, distribution pattern and root growth form of Tamarix chinensis were surveyed at natural stand in Shiwha Lake, from June to July in 2005. T, chinensis grew in the range of 350 m towards north-south and 270 m in east-west direction. The mean number of stems germinated from same root system was 1.9. On the stem base, the numbers of living and dead plants were 1,398 and 114, respectively. Mean perimeter and height of 1,398 plants were $5.9{\pm}3.2$ cm and $159{\pm}51$ cm, respectively. By dividing into 10 classes based on the perimeter size, the largest number of plants were included in the second smallest class category. However, by dividing into 10 classes on the bases of plant height, variation in the number of plants along the height showed normal distribution curve. The heights of dead plants were small in perimeter but diverse in height. On the root base, the number of plants was the greatest in the smallest size class, and conspicuously decreased with size increment. Distribution of T. chinensis was clumped pattern. Age of the largest plant was 8-year. T. chinensis had two types of root growth. One was horizontal growth in the periphery of soil surface, and the other vertical growth.

• Journal of Korean Society of Forest Science
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• v.105 no.2
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• pp.231-237
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• 2016

This research was conducted in order to examine whether the Woodgrab short-wood logging method, most widely used logging method in Korea, is more favorable than other logging methods in terms of productivity and profitability. For the comparative purposes, whole-tree logging methods with cable yarding system using a swing yarder and a tower yarder were evaluated. The productivity and the profitability of the logging operations by the machine types on a L. kaempferi stand were estimated by simulating logging processes based on bucking patterns and the results were compared. As a result, the Woodgrab short-wood logging system showed the most favorable results in terms of skidding productivity and operating cost. On the contrary, the system was the least profitable among the three logging methods. Main reason is that while the system may be beneficial in terms of operation productivity, it is restricted to produce only short logs mainly for low quality raw materials such as pulp, bolts, etc. which are sold at cheap prices.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.7 no.2
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• pp.271-286
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• 2000

This study is designed to investigate what elders think about the meaning of aging. We have used Q-methods to identify meaning of aging from elders, and developed self-referenced surveys to analyze characteristics In this study, we used a non-structured method to select Q sampling. From 183 Q populations, we selected 36 Q sampling. A total of 32 persons sixty-years or older were randomly selected for P samples, When the Q-sorting was complete, we interviewed the participants at both end of the extremes(agree or disagree), and documented their responses. We used PC QUANL to process the data and used principal component analysis for Q factor analysis. There were five subjective types for the meaning of aging by elders. Of the 32 P-samples of elders, 11 were identified as Type 1, 7 as Type 2, 2 as Type 3, 8 as Type 4, and 4 as Type 5. Type 1 : 'Matured elders' Elders wished the well being of their children, thought older persons should maintain good health, worried about becoming senile, and dependent God believing in life after death. Type 2 : 'Assertive-Rights' Elders categorized as Assertive-Rights insisted on their rights to life as a person. Type 2 elders characterized themselves as people who should keep themselves healthy, become weak and lack sexual desires, act selfish like a child, need to be protected, and be financially independent. Type 3 : 'Passive-Dependents' Elders characterize themselves as those who pray for their children's well being, worry about the children even after their death. and becoming senile. Type 4 : 'Hopeless' The 'Hopeless' type of elders characterized aging as a time to pray for their children, insignificant beings, thoughts were selfish and child-like, poor, worried about going senile, regret their life overall, and preferred to die than to live as an old person. Type 5 : 'Attached-Present' The 'Attached-Present' type of elders thought elderly characterized themselves as acting selfish and child-like, wiser, anxious, regret their life, stand aloof of greed and worldly things, being a model for the society, and deserving to be treated with filial respect. Thus far, Korean elders seemed to have a positive and negative meaning of aging due to the current changes in the society, value system, and family structures. The above five subjective meanings of aging confirm that we need to approach and nurse the elderly differently. Years of aging are a part of and a natural process of life with various physical, psychological, and sociological changes. Nurses need to assist elderly to find the positive meaning of their life by providing appropriate physical, psychological, and social support at an earlier stage in nursing. Based on this study, we could derive the following two implication from the perspectives of science of nursing to care for elders. 1) Based on the studies investigating the type of meaning of aging, we could develop tools to assist in nursing intervention programs for elderly. 2) Based on research on the meaning of aging for different developmental stages of life, we could develop a model for roles for different family members in nursing and caring for the elders.

• The Journal of the Korea Contents Association
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• v.13 no.2
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• pp.400-411
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• 2013

OCB(organizational citizenship behavior) is a employee behavior that goes above and beyond the call of duty, that is discretionary and not explicitly recognized by the employing organization's formal reward system, and that contributes to organizational effectiveness. In a word, OCB has great potential as a organizational slack. As such, researchers have been showing great interest in the antecedents of OCB, and as a result, now we can meet so many antecedents of OCB from individual level variables to group or organizational level variables that are said to be important in explaining OCB. Additionally each of these variables is known to have its own sound logic and statistically significant effect on OCB. However the results of these studies are so fragmented that researchers have a great difficulty in drawing some meaningful or coherent conclusions. In this context, we try to applicate Q-methodology to find more coherent way of explaining the motives of OCB, and briefly speaking, we find four types of the motives of OCB, that is norm-based, instrumentality-based, trait-based, and avoidance-based type. Among these the last avoidance-based type is especially interesting, because we can't find any remarks on this type in the previous studies. The paper ends with suggestions for future research directions. We expect that these suggestions could be a foundation on which more developed and coherent OCB theories stand. We don't see this approach supplanting earlier efforts; rather we believe this can offer more detailed explanation in addition to those provided by other approaches.

• Journal of Korean Society of Forest Science
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• v.87 no.3
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• pp.341-346
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• 1998

The effects of CaO, $CaO+MgSO_4$, and $CaO+MgSO_4$+compound fertilizers(NPK) on soil chemical properties of acidified forest soils were studied in Quercus spp. and Pinus rigida stands in Mt. Namsan and Mt. Surak in urban areas, and Kwangnung in a mountain area. The soil samples were collected in November 1995 after every year fertilization from November 1991 through April 1995. The fertilizations affected soil chemical properties. Soil pH increased after fertilizations compared with control. However, the effect was different between the stand types and the areas. Organic matter and total nitrogen content were not changed, while exchangable cations such as calcium and magnesium increased after fertilizations. However, these ration concentrations after fertilizer treatments were lower in P. rigida than in Quercus spp. stands. These rations also showed increased leaching characteristics more in the urban area than in the mountain area.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.365-377
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• 1997

Much of the Cumberland Plateau of Tennessee, USA is in mixed hardwoods for which there are no applicable growth and yield predictors. Use of site index as a variable in growth and yield prediction models is limited in most stands because their history is not known and many may not be even-aged. Landtypes may offer an alternative to site index for these mixed stands because they were designed to include land of about equal productivity. To determine vegetation by landtype, dependency between landtype and detailed forest type was tested with Chi-square. Differences in productivity among landtypes were tested by employing regression analyses and analysis of variance(ANOVA). Basal area growth was fitted to the nonlinear models developed by Moser and Hall(1969). Basal area growth and volume growth were also predicted as a function of initial total basal area and initial volume with linear regression by landtype and by landtype class. Differences in basal area growth and volume growth by landtype were tested with ANOVA. Dependency between site class and landtype was tested with Chi-square. Vegetation types seem to be related to landtypes in the study area although the validity of the test is questionable because of a high proportion of sparsely occupied cells. No statistically significant differences in productivity among landtypes were found in this study.

• Journal of Distribution Research
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• v.12 no.3
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• pp.1-21
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• 2007

This study introduces 'Free Market' that was recently developed in front of Hongik university. 'Free market', as a place for transactions for art products produced by artists or prospective artists, is held regularly every Saturday in front of Hongik university. This study collected data through in-depth interviews with participants and participant observations at the market to analyze the success factors of 'Free Market'. We described development process, unique characteristics of 'Free Market' and new experiential values that the market provide to the participants. This free market was introduced as roadside stand in the middle of 1990s when some artists started selling their works. It passed through the growth stage after it staged the event that had mixed characteristics of 'flee market' and 'art market' at local festivals in 2001. In 2002 Sin-Chon culture forum directedculture-oriented market and the market has been developed as a current 'Free Market'. Recently 'Free Market' is comprised of steps, artists, and customers who voluntarily participated in the market. The market is held regularly every Saturday and provide various types of programs for the participants. Major characteristics of this free market were summarized as 'complex space' and 'role transition', and these characteristics provided the participants new experiential values such as 'freedom', 'emergent experiences', 'social interaction' and 'hero of festivals' through the participant role. We interpret that 'Free Market' has been successfully settled down as a new type of retail store based on these new experiential values. Therefore, this case provides very useful implications that unique experiential values that a store provides to the customers can be major sources of store competitive advantages.

• Korean Journal of Environment and Ecology
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• v.32 no.2
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• pp.185-202
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• 2018

Many ecological studies regarding forest succession, which is the process of arriving at climax forest through ecological changes, have suggested that Carpinus laxiflora is the leading tree type of the climax forest of temperate zone in South Korea. However, most of these studies on C. laxiflora forest have focused on vegetation structure and succession process in specific areas or regional physiognomical forest communities, and thus some may question whether it is rational to consider C. laxiflora forest as the climax forest in South Korea's temperate forest zone. The purpose of this study was to analyze the vegetation classification, species composition, and stratum structure and to investigate the succession tendency with the vegetation data collected from C. laxiflora forests in 75 quadrates in 17 mountains between 2014 and 2017. We used the phytosociological method to analyze the vegetation structure and the importance value to analyze the stratum structure. The results showed the floristic composition of 6 vegetation units and 9 species groups. The hierarchy of the C. laxiflora community group was represented by the Ulmus laciniata community, Corylus heterophylla community (subdivided Quercus aliena group and Corylus heterophylla typical group), and Rhododendron schlippenbachii community (subdivided Fraxinus chiisanensis group, Carpinus tschonoskii group, and Rhododendron schlippenbachii typical group). Successional tendency of C. laxiflora forest based on the importance of each layer is predicted to be the total of three types such as to maintain the stand (vegetation units 2, 3, and 6), to success the Carpinus cordata forest (vegetation units 1 and 4), and to success Quercus acuta forest (vegetation unit 5).

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.588-588
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• 2013

Nanoscale noble-metals have attracted enormous attention from researchers in various fields of study because of their unusual optical properties as well as novel chemical properties. They have possible uses in diverse applications such as devices, transistors, optoelectronics, information storages, and energy converters. It is well-known that nanoparticles of noble-metals such as silver and gold show strong absorption bands in the visible region due to their surface-plasmon oscillation modes of conductive electrons. Silver nanocubes stand out from various types of Silver nanostructures (e.g., spheres, rods, bars, belts, and wires) due to their superior performance in a range of applications involvinglocalized surface plasmon resonance, surface-enhanced Raman scattering, and biosensing. In addition, extensive efforts have been devoted to the investigation of Gold-based nanocomposites to achieve high catalytic performances and utilization efficiencies. Furthermore, as the catalytic reactivity of Silver nanostructures depends highly on their morphology, hollow Gold nanoparticles having void interiors may offer additional catalytic advantages due to their increased surface areas. Especially, hollow nanospheres possess structurally tunable features such as shell thickness, interior cavity size, and chemical composition, leading to relatively high surface areas, low densities, and reduced costs compared with their solid counterparts. Thus, hollow-structured noblemetal nanoparticles can be applied to nanometer-sized chemical reactors, efficient catalysts, energy-storage media, and small containers to encapsulate multi-functional active materials. Silver nanocubes dispersed in water have been transformed into Ag@Au nanoboxes, which show highly enhanced catalytic properties, by adding $HAuCl_4$. By using this concept, $SiO_2$-coated Ag@Au nanoboxes have been synthesized via galvanic replacement of $SiO_2$-coated Ag nanocubes. They have lower catalytic ability but more stability than Ag@Au nanoboxes do. Thus, they could be recycled. $SiO_2$-coated Ag@Au nanoboxes have been found to catalyze the degradation of 4-nitrophenol efficiently in the presence of $NaBH_4$. By changing the amount of the added noble metal salt to control the molar ratio Au to Ag, we could tune the catalytic properties of the nanostructures in the reduction of the dyes. The catalytic ability of $SiO_2$-coated Ag@Au nanoboxes has been found to be much more efficient than $SiO_2$-coated Ag nanocubes. Catalytic performances were affected noteworthily by the metals, sizes, and shapes of noble-metal nanostructures.

• Journal of Astronomy and Space Sciences
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• v.34 no.4
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• pp.271-280
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• 2017

This study presents the application of satellite laser ranging (SLR) to orbit determination (OD) of high-Earth-orbit (HEO) satellites. Two HEO satellites are considered: the Quasi-Zenith Satellite-1 (QZS-1), a Japanese elliptical-inclinedgeosynchronous-orbit (EIGSO) satellite, and the Compass-G1, a Chinese geostationary-orbit (GEO) satellite. One week of normal point (NP) data were collected for each satellite to perform the OD based on the batch least-square process. Five SLR tracking stations successfully obtained 374 NPs for QZS-1 in eight days, whereas only two ground tracking stations could track Compass-G1, yielding 68 NPs in ten days. Two types of station bias estimation and a station data weighting strategy were utilized for the OD of QZS-1. The post-fit root-mean-square (RMS) residuals of the two week-long arcs were 11.98 cm and 10.77 cm when estimating the biases once in an arc (MBIAS). These residuals were decreased significantly to 2.40 cm and 3.60 cm by estimating the biases every pass (PBIAS). Then, the resultant OD precision was evaluated by the orbit overlap method, yielding three-dimensional errors of 55.013 m with MBIAS and 1.962 m with PBIAS for the overlap period of six days. For the OD of Compass-G1, no station weighting strategy was applied, and only MBIAS was utilized due to the lack of NPs. The post-fit RMS residuals of OD were 8.81 cm and 12.00 cm with 49 NPs and 47 NPs, respectively, and the corresponding threedimensional orbit overlap error for four days was 160.564 m. These results indicate that the amount of SLR tracking data is critical for obtaining precise OD of HEO satellites using SLR because additional parameters, such as station bias, are available for estimation with sufficient tracking data. Furthermore, the stand-alone SLR-based orbit solution is consistently attainable for HEO satellites if a target satellite is continuously trackable for a specific period.