• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.239-246
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• 2013

This study observed changes of understory vegetation to evaluate the role of forest aggregate after 15% aggregated retention harvest in mature oak forest (> 100 years) in Gyungsangbukdo Bonghwagun in 2010 and 2011. Spontaneous responses of understory vegetation cover (%), species richness, abundance of plant growth forms (herbaceous and woody plants), and overall attributes (by Ordination analysis) were estimated in aggregate area (0.15 and n=36) and clear cut area (0.85 and n=192) in experimental site and control site (1 and n=300). Based on ordination analysis, overall change of species composition in aggregated sites were relatively lower than in harvest area. Right after treatment, total cover of cutted area slightly decreased from 15.6% to 14.7%, and species richness increased from 14 species to 22 species. Cover and richness in the both of aggregate and control sites increased. In plant growth forms, 15% aggregate harvest revealed positive effects on the abundance (cover and richness) of herbaceous plants than woody group. After retention treatment, overall, edge effect likely played major component of vegetation changes in aggregate forest and in harvested area, mechanical damage from harvest operation and change of forest structure by clear cutting were critical. As pre-treatment data, which are rare in ecological studies in Korea, were critical for interpretation between patterns that may have arisen from spatial distributions in the original forest, our experimental design have higher opportunity for long term monitoring on the effect of forest aggregate and vegetation regeneration in clear cutted area.

• Journal of Korean Society of Archives and Records Management
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• v.3 no.2
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• pp.52-77
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• 2003

Borimsa was first built by Wonpyo, the great Buddhist priest of Whaum branch, in the year of 759 A.D. And Later the priest Chejing converted to Zen Buddhism in the year of 858 A.D., Borimsa got the central status of the Zen Buddhism, and was so prospered during the Chosun period. This research is the conservation treatment of the Buddhist literatures and the "Wolinsukbo" Vol.25, discovered in 1995 from the Four Devas of Borimsa, Buddhist Temple at Jangheung County, in the viewpoint of the bibliography. "Wolinsukbo" Vol.25 is consist of 142 pages and the size is of 22cm width, 32.3cm of length, and 2.8cm of depth. And also have the five-pinned eye revisor. The pre-conservation condition of this book was partly spotted by the permeated rain, and the cover pages being deeply spoiled. The conservation treatment was done in the sequences of 1) 1st linsing, 2) repairing and correcting, 3) 2nd linsing and conservation, 4) cutting and binding. The post-conservation condition of "Wolinsukbo" Vol.25 is of, 9 pages including covers are added, total 151 pages, and the size being 22.5 cm width, 32.7cm of length, and 3.2cm of depth.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.5
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• pp.799-810
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• 2022

Welding work is a production work method widely used throughout the industry, and various types of welding technologies exist. In addition, many methods are being studied to automate these welding operations using robots, but in the ship manufacturing field, welding such as painting, cutting, and grinding is also the most common operation, but the manual operation ratio is higher than in other industries. Such a high manual labor ratio in the field of ship manufacturing not only causes quality problems and production delays according to the skill of workers, but also causes problems in the supply and demand of manpower. Therefore, this paper analyzed the reason why the automation rate is low in welding work at ship manufacturing sites compared to other industries, and analyzed the production process and field environment for small and medium-sized ship manufacturing companies that repeatedly manufactured with a small quantity production method. Based on the analysis results, it is intended to propose a robot system that can easily move between workplaces and secure uniform welding quality and productivity by collaborating simple welding tasks with humans. Finally, the simulation environment is constructed and analyzed to secure the suitability of robot system application to current production site environment, work process, and productivity, rather than to develop and apply the proposed robot system. Through such pre-simulation and robot system suitability analysis, it is expected to reduce trial and error that may occur in actual field installation and operation, and to improve the possibility of robot application and positive perception of robot system at ship manufacturing sites.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.363-368
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• 2021

Ship engine rooms have improved automation systems owing to the advancement of technology. However, there are many variables at sea, such as wind, waves, vibration, and equipment aging, which cause loosening, cutting, and leakage, which are not measured by automated systems. There are cases in which only one engineer is available for patrolling. This entails many risk factors in the engine room, where rotating equipment is operating at high temperature and high pressure. When the engineer patrols, he uses his five senses, with particular high dependence on vision. We hereby present a preliminary study to implement an engine-room patrol robot that detects and informs the machine room while a robot patrols the engine room. Images of ship engine-room equipment were classified using a convolutional neural network (CNN). After constructing the image dataset of the ship engine room, the network was trained with a pre-trained CNN model. Classification performance of the trained model showed high reproducibility. Images were visualized with a class activation map. Although it cannot be generalized because the amount of data was limited, it is thought that if the data of each ship were learned through transfer learning, a model suitable for the characteristics of each ship could be constructed with little time and cost expenditure.

• The Journal of the Petrological Society of Korea
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• v.15 no.4 s.46
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• pp.180-193
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• 2006

The Gilan area in the central-northern part of Uiseong Block of Cretaceous Gyeongsang Basin is composed of Precambrian metamorphic rocks, Triassic Cheongsong granite, Early Cretaceous Hayans Group, and Late Cretaceous-Paleocene igneous rocks. In this area, the faults of various directions are developed: Oksan fault of $NS{\sim}NNW$ trend, Gilan fault of NW trend, Hwanghaksan fault of WNW trend, and Imbongsan fault of EW trend. Several fracture sets with various geometric indicators, which determine their relative timing (sequence and coexistence relationships) and shear sense, we well observed in the Cheongsong granite, the basement of Gyeongsang Basin. The aim of this study is to determine the development sequence of extension fractures and the movement sense of shear fractures in the Gitan area on the basis of detailed analysis of their geometric indicators (connection, termination, intersection patterns, and cross-cutting relations). This study suggests that the fracture system of the Gilan area was formed at least through seven different fracturing events, named as Pre-Dn to Dn +5 phases. The orientations of fracture sets show (W) NW, NNW, NNE, EW, NE in descending order of frequency. The orientation and frequency patterns are concordant with those of faults around and in the Gilan area on a geological map scale. The development sequence and movement sense of fracture sets are summarized as follows. (1) Pre-Dn phase: extension fracturing event of $NS{\sim}NNW$ and/or $WNW{\sim}ENE$ trend. The joint sets of $NS{\sim}NNW$ trend and of $WNW{\sim}ENE$ trend underwent the reactivation histories of sinistral ${\rightarrow}$dextral${\rightarrow}$sinistral shearing and of (dextral${\rightarrow}$) sinistral shearing with the change of stress field afterward, respectively. (2) Dn phase: that of NW trend. The joint set experienced the reactivations of sinistral${\rightarrow}$dextral shearing. (3) Dn + 1 phase: that of $NNE{\sim}NE$ trend. The joint set was reactivated as a sinistral shear fracture afterward. (4) Dn +2 phase: that of $ENE{\sim}EW$ trend. (5) Dn +3 phase: that of $WNW{\sim}NW$ trend. (6) Dn+4 phase: that of NNW trend. The joint set underwent a dextral shearing after this. (7) The last Dn +5 phase: that of NNE trend.

• Journal of The Korean Association For Science Education
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• v.24 no.3
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• pp.442-458
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• 2004

This study was conducted to develop a plan for a large-scale implementation of the Girl Friendly Science Program based on the results of analysis and investigation of its current pilot implementation, Girl Friendly Science Program materials, which was first developed in 1999 with the support from Ministry of Gender Equality, consist of 1) five theme-based units that are specifically targeted individual students' unique ability, aptitude, and career choice, and 2) differentiated learning materials for 7th through 10th grade female students. All the materials are available at the homepage (http://tes.or.kr/gfsp.cgi) of 'Teachers for Exciting Science(the organization of science teachers in Seoul area)'. Since the materials are well organized by topic and grade level and presented in both Korean word process document and html format, anyone can easily access to the materials for their own instructional use. Ever since its launch the number of visitors to the homepage has been constantly increasing. The evaluation results of the current pilot implementation of the materials that targeted individual students' ability and aptitude showed that it scored high in terms of its alignment to the original purpose, content, level, and effectiveness to implement in classrooms. However, its evaluation scores were low in terms of the convenience for teachers to guide the materials, and its organization and operation. The results also showed a significant change in students' perception of science, and students' positive experiences of science through various interdisciplinary activities. On the other hand, the evaluation of students' experiences with the materials showed that students' assessment about an activity was largely depending on a success or failure of their experiences. Overall, students' evaluation of activities scores were low for simple activities such as cutting off or pasting papers. According to students' achievement test results, differences between pre and post test scores in the Affective Domain was statistically significant (p<0.05), but not in Inquiry Domain. Based on teachers observations, numerous schools where have run this program reported that students' abilities to cooperate, discuss, observe and reason with evidences were improved. In order to implement this program in a larger scale, it is critical to have a strong support of teachers and induce them to change their teaching strategy through building a community of teachers and developing ongoing teacher professional development programs. Finally, there still remain strong needs to develop more programs, and actively discover and train more domestic woman scientists and engineers and collaborate with them to develop more educational materials for girls in all ages.

• Journal of Korean Society of Forest Science
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• v.96 no.1
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• pp.21-28
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• 2007

This study was conducted to investigate how the qualities of the stream water vary during the event in the regrowth and rehabilitation catchments in Yangju, Gyeonggido, from June to September 2005. During the observation periods, we sampled the stream water continuously by an auto-sampler (ISCO, 6712FR). The sampled waters were analyzed for suspended solid concentration, electrical conductivity and pH. The suspended solid concentration during the event increased concurrently with the stream flow. The peak of suspended solid concentration usually precedes the peak flow. The maximum value of suspended solid concentration was 420.89 mg/l in the event 1 at the regrowth catchment. Among the events simultaneously sampled at both catchments, the maximum values of suspended solid concentration were 212.8 mg/l and 58.24 mg/l in the event 3 at the regrowth and rehabilitation catchment respectively. The maximum value of EC in each event showed in the early stage of rising limb. EC decreased during the rising limb, and then showed minimum value at peak flow. EC gradually increased to pre-event value after minimum one. pH varied in similar pattern with EC. The maximum value of suspended solid concentration during each event was 2.8 to 4.3 times higher at the regrowth catchment than at the rehabilitation catchment. And the EC during each event was higher at the regrowth catchment than at the rehabilitation catchment. This results indicate that a disturbed forest soil during clear cutting at regrowth catchment still has been unstable.

• Restorative Dentistry and Endodontics
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• v.35 no.2
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• pp.88-95
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• 2010

The purpose of this study was to compare the root canal shaping ability of 4 rotary NiTi instruments in simulated root canals. For the preparation of thirty two curved root canals, Mtwo instruments using "single length"technique, and Profile, ProTaper Universal, and K3 using crown-down technique (N = 8) were used. All canal samples were prepared by reaching an apical canal size of #30. Pre- and post-instrumentation digital images were recorded and an assessment of canal shape was determined using a computer image analysis program SigmaScan Pro (Systat Software Inc., San Jose, CA, USA). The changes of the dimension of inner walls of canals, (2) the changes of the dimension of outer walls of canals, and (3) the centering ratio were measured at 7 measuring points, and then data were statistically analyzed using one-way ANOVA and Duncan's test. The results were as below; 1. The root canal shaping ability of Profile was significantly faster than that of other rotary NiTi instruments (p < 0.05). 2. The deformation and fracture of all instruments used for this study were not experienced. 3. In the degree of changes of the dimension of inner walls of canals, Profile demonstrated the lowest changes of the dimension of inner walls of canals except at the measuring points of the 1 and 2 mm (p < 0.05). However, the ProTaper Universal showed the highest changes of the dimension of inner walls of canals at all measuring points (p < 0.05). 4. In the degree of changes of the dimension of outer walls of canals, Mtwo demonstrated the lowest changse of the dimension of outer walls of canals except at the measuring point of the 1 mm (p < 0.05). However, Profile exhibited the highest changes of the dimension of outer walls of canals at the measuring points of 3 and 4 mm and ProTaper Universal and K3 showed the largest changes of the dimension of outer walls of canals at the measuring points of 1, 2, 6, and 7 mm (p < 0.05). 5. In degree of centering ratio, Profile demonstrated the least centering ratio comparing with the centering ratio shown by other NiTi instruments at the measuring points of 1, 4, 5, and 6 mm. Results suggest that in the coronal part of canal preparation, active cutting files such as ProTaper Universal may efficiently flare the canal orifice and form a better taper, and in the apical part of the canal, files which have a better centering ability such as Profile may maintain the original canal curvature and reduce the shaping time.

• Journal of Food Hygiene and Safety
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• v.27 no.4
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• pp.420-426
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• 2012

The purpose of this study was to identify control points through microbiological hazard analysis in the manufacturing processes of starch noodles. Samples were collected from the ingredients, manufacturing processes, equipment and environment. Microbiological hazard assessments were performed using aerobic plate counts (APC), Enterobacteriaceae (EB), E. coli and five pathogens including B. cereus, E. coli O157:H7, L. monocytogenes, Salmonella spp., and S. aureus. The APC levels in raw materials were from 2.12 to 3.83 log CFU/g. The contamination levels after kneading were 4.31 log CFU/g for APCs and 2.88 log CFU/g for EB counts. APCs decreased to 1.63 log CFU/g and EB were not detected after gelatinization, but their levels slightly increased upon cooling, cutting, ripening, freezing, thawing, and separating. The reuse of cooling and coating water would be a critical source of microbial increase after cooling. After drying, APCs and EB counts decreased to 5.05 log CFU/g and 2.74 log CFU/g, respectively, and the levels were maintained to final products. These results suggest that the cooling process is a critical control point for microbiological safety, and the cooling water should be treated and controlled to prevent cross contamination by pre-requisite program.

• Restorative Dentistry and Endodontics
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• v.30 no.1
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• pp.38-48
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• 2005

The purpose of this study was to compare and evaluate the shaping ability of the three different Ni-Ti file systems used by undergraduate students. Fifty undergraduate students prepared 150 simulated curved root canals in resin blocks with three Ni-Ti file systems - $ProFile^{(R)}$ (PF), Manual $ProTaper^{(R)}$ (MPT), Rotary $ProTaper^{(R)}$ (RPT). Every student prepared 3 simulated root canals with each system respectively. After root canal preparation, the Ni-Ti files were evaluated for distortion or breakage Assessments were made according to the presence of various types of canal aberrations. The pre- and post-instrumented canal images were attained and superimposed. The instrumented root canal width were measured and calculated for the net transportation (deviation) and the centering ratio. Under the condition of this study, both $ProTaper^{(R)}$ systems allowed significantly more removal of root canal wall than the $ProFile^{(R)}$ system. In the important other aspects such as the centering ratio, there was no significant differences between the systems. Novice dental students were able to prepare curved root canals with any kinds of Ni-Ti file systems with little aberration and great conservation of tooth structure. Students want to learn effective methods and at the same time simple rotary procedures. The rotary $ProTaper^{(R)}$ systems were one of the most compatible to these students from the point of view of cutting ability The $ProFile^{(R)}$ system was also compatible in safe and gentle shaping.