• Journal of the Korean Wood Science and Technology
• /
• v.38 no.6
• /
• pp.490-497
• /
• 2010

Radial variations in the lengths of wood fibers and vessel elements in the stem of chestnut (Castanea crenata) grown in Korea were investigated to get some fundamental information for efficient use of wood. Seven chestnut cultivars (Tanzawa, Ibuki, Arima, Ginyose, Tsukuba, Riheiguri, and Mansung) were examined in this study. The lengths of wood fibers and vessel elements were measured and analyzed by an optical microscope and an imaging analysis system. In all chestnut cultivars, the wood fiber length of latewood was longer than that of earlywood, and increased with the increase of growth ring number. Similarly, vessel element length of latewood was longer than that of earlywood, and showed increasing tendency with the increase of growth ring number. Consequently, it was considered that the lengths of wood fibers and vessel elements could be used for separating juvenile wood from adult wood in the chestnut stem.

• The Journal of the Korea Contents Association
• /
• v.21 no.2
• /
• pp.594-603
• /
• 2021

This study explored the moderating effects of task difficulty for flow, learning motivation, and interesting in distant PBL classes of pre-service teachers. For this, the research model was constructed by analyzing previous studies. The research model verification was conducted by 105 students of taking courses in the curriculum. The distant PBL used a real-time video conference system. Cooperative activities were carried out in real time. After the end of the distant PBL activity, the level of learning motivation, interesting, flow, and task difficulty perception were measured. The collected data were analyzed using a test of the structural model invariance across the groups using a structural equation model. This analysis verifies the difference in path coefficients between measurement models. The control effect of task difficulty was verified through the difference in path coefficient. As a result, it was verified that interesting mediates the influence of learning motivation on flow. And the moderating effect of the perceived task difficulty appeared on the path from learning motivation to interesting.

• Journal of the Korean Wood Science and Technology
• /
• v.30 no.2
• /
• pp.79-86
• /
• 2002

Anatomical characteristics of Mulpurenamu (Korean ash, Praxmus rhynchopbylla), Deulmaenamu (Manshurican ash, Fraxinus mandsburica) and Sheamulpure (Sieboldiana ash, Fraxinus sieboldiana) grown in Korea were examined by an optical microscopy and an image analysis. Some characteristics such as boundary of annual rings, shape and size of vessel elements, arrangement of axial parenchyma cells in cross section, and cell volumetric composition showed significant differences between the sample species. In radial variation of elements, fiber length and vessel size increased from the pith for about 10 to 15 years and then reached a more or less constant. The results of this study can be used for identification of wood and indices of wood quality in Fraxinus spp.

• Journal of Korea Entertainment Industry Association
• /
• v.15 no.1
• /
• pp.131-142
• /
• 2021

Purpose: Clinical practicums via non-face-to-face methods were inevitable due to the COVID-19 pandemic. We developed an online program for emergency nursing care and identified the feasibility of the program and the learning achievements of students. Methods: This was a methodological study. The program was developed by three professors who taught theory and clinical practicum for adult nursing care and clinical experts. Students received four hours of video content and two task activities every week in four-week program. Real-time interactive video conferences were included. Qualitative and qualitative data were collected. Results: A total of 96 students participated in the program. The mean score for overall satisfaction with the online program was 4.72(±1.02) out of 6. Subjects that generally had high learning achievement scores were basic life support care, fall prevention, nursing documentation, infection control, and anaphylaxis care. As a result of a content analysis of 77 reflective logs on the advantages of this program, students reported that "experience in applying nursing process," "case-based learning and teaching method," and "No time and space constraints" were the program's best features. Conclusion: Collaboration between hospitals and universities for nursing is more important than ever to develop online content for effective clinical practicum.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.35 no.2
• /
• pp.93-101
• /
• 1999

A simple experimental method was used in an attempt to realize the elevation of the fishing ability of purse seine in the sea area of Cheju Island, the changes of seine volume and tension in the purseline during pursing. Experiments carried out on the six types simplified reduced model seines which were made of knotless nettings. The nettings were woven in different leg length 4.3, 5.0, 5.5, 6.0, 6.6 and 7.7mm of polyester 28 tex two threads two-ply twine, and each of the seines were named I, II, III, IV, V and Ⅵ seine. Dimension of seine models were 450cm for corkline and 85cmfor seine depth, each seines rigged up 160g of float for a floatline and 50g (underwater weight) of lead for a leadline. These model purse seines were made of the scale of 1/200 of its full scale, a 120 ton in the near sea of Cheju Island. Designing and testing for the model purse seines were based on the Tauti's law. Experiments were measured in the observation channel of a flume tank at the static conditions set up shooting and pursing equipments. Motion of purse seine during purse line was recorded by the two sets video camera for VTR which were placed in top and front of the model seine. The reading coordinate of seine volume carried out by the video digitization system, disk data for the purseline tension. An analysis were performed on the changes seine volume and tension in the purseline during pursing. The results obtained were as follows: 1. The seine volume during pursing was largest for Ⅵ seine with smallest d/l followed by V, IV, III, II and I seines, and tension in the purseline was small. 2. Seine volume during pursing can be expressed by the following equation; CVt=l-EXP[｛2.79 (d/l）＋0.35｝t-33.37 (d/l) ＋ 0.57] Where CVt is volume ratio, d is twine diameter, l is leg length and t is pursing time (sec). 3. Tension in the purse line during pursing can be expressed by the following equation; T= 1- EXP ｛0.57t ＋ 13.36 (d/l)+2.97｝ Where T is tension (kg) in the purseline during pursing.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.9
• /
• pp.1482-1491
• /
• 2013

The purpose of this study was to investigate the safety accidents and physical fatigues of school foodservice employees. Out of 300 questionnaires distributed from December 1~20, 2011, 276 responded. After excluding 54 incomplete questionnaires, 222 (usage rate: 74%) were examined in the final analysis. First, our results showed that in terms of safety accidents, most received bruises (92.8%), followed by burns (73.0%), cuts and lacerated wounds (69.4%), sprains (47.7%), falls (42.8%), fractures/dislocations (31.5%) and electric shock (2.7%). Second, we found that the average degree of physical fatigue of school foodservice employees was 3.65 based on the 5-point Likert scale. Specifically, pain in the arms and wrist was rated the highest, at 4.18. Third, results showed that the factors affecting physical fatigue were 'class of school' (P<0.05), 'frequency of meal serving per day' (P<0.05), 'no. of meals served per day' (P<0.001), 'no. of meals per employee' (P<0.05) and 'warm-up exercise before starting work' (P<0.05). This means that foodservice employees serving middle schools, serving meals three times per day, serving more than 1,000 meals per day, and serving more than 111 meals per employee perceive higher levels of physical fatigue. In addition, the physical fatigue of those who perform warm-up exercises before starting work was significantly lower than those who do not perform warm-up exercises before work (P<0.05). In conclusion, the frequently occurring major safety accidents of school foodservice employees were bruises and burns. An increase in workload also leads to the increasing physical fatigue of school foodservice employees. Thus, to lower the physical fatigue of school foodservice employees, school foodservice employees should be encouraged to perform warm-up exercises before staring work and new staffing guidelines for school foodservice employees should be developed.

• Korean Journal of Plant Taxonomy
• /
• v.52 no.3
• /
• pp.184-195
• /
• 2022

The invasive alien species Brassica tournefortii Gouan (Brassicaceae) is herein reported for the first time in Korea, from Gunsan-si, Gochang-gun, and Jeju-si. Brassica tournefortii can easily be distinguished from B. juncea and B. napus by its dense stiff hairs at the base of the stem and leaves, basally and distally branched stems, partially dehiscent fruits, and seeds that become mucilaginous in the presence of moisture. Although some taxonomists have classified this species as belonging to Coincya Rouy based on its fruit and seed characteristics, the existence of one vein on the fruit valves and our maximum likelihood analysis using internal transcribed spacer sequences placed it in Brassica. Distribution data, photographs, and a description of B. tournefortii are presented herein. Moreover, potential changes in the distribution of B. tournefortii were predicted under different climate scenarios, but our analysis showed that the probability of the spreading of this species is low. Nevertheless, continuous monitoring is necessary for an accurate assessment. The results of the present study can be used to conduct an invasion risk assessment and can assist with the effective management of this invasive alien species.

• Journal of the Korean Institute of Gas
• /
• v.26 no.3
• /
• pp.10-20
• /
• 2022

About 21% of domestic chemical accidents are caused by transport vehicles for the past 10 years in Korea. Also, ammonia is a chemical substance with the largest number of accidents, 82 out of 672. In this study, supposed seasonal alternative scenario and worst scenario in case of releasing ammonia during bunkering it from tank lorry to fishing vessel and interpreted seasonal impact and range through Python, ALOHA, Probit analysis. Radiation impact range of possibility for 2nd burn and for maximum radiation in winter scenario, which is one of the alternative scenarios, was the highest(range: 41m, radiation: 5.01kW/m²) while overpressure impact was less than minimum standard of impact. And toxicity impact range(EPRG-2) of the summer scenario was the widest(5.0km) and took a very high death rate near accident area(port area, tourist area) according to Probit analysis. the wort scenario had a similar impact and range of summer scenario.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.30 no.1
• /
• pp.93-102
• /
• 2004

Recently, the golden age of herbal cosmetics has come. Along with active introduction of oriental herbal lines, diversification of distribution channels is designated as a major feature. In this background, the present study attempts to consider the domestic market for oriental herbal cosmetics, which is growing rapidly with the introduction of various new brands, and examine the perceptions of this new type of cosmetics by women consumers based on their purchase behaviors, and search for the ways for its promotion and development. A survey was conducted to adult women consumers aged 19∼60 residing in Seoul or Gyeonggi-do. Out of a total of 430 surveys distributed, 350 answer sheets were used for the analysis Among the results, the first-hand information on the herbal cosmetics market, their usage, and the consumer needs obtained in the present study will serve as a fundamental data for planning the marketing strategies for the oriental herbal cosmetics.

• The korean journal of orthodontics
• /
• v.27 no.5 s.64
• /
• pp.815-824
• /
• 1997

The purpose of this study is to develop the basic algorithm for the finite element method modeling of individual malocclusions. Usually, a great deal of time is spent in preprocessing. To reduce the time required, we developed a standardized procedure for measuring the position of each tooth and a program to automatically preprocess. The following procedures were carried to complete this study. 1. Twenty-eight teeth morphologies were constructed three-dimensionally for the finite element analysis and saved as separate files. 2. Standard brackets were attached so that the FA points coincide with the center of the brackets. 3. The study model of a patient was made. 4. Using the study model, the crown inclination, angulation, and the vertical distance from the tip of a tooth was measured by using specially designed tools. 5. The arch form was determined from a picture of the model with an image processing technique. 6. The measured data were input as a rotational matrix. 7. The program provides an output file containing the necessary information about the three-dimensional position of teeth, which is applicable to several finite element programs commonly used. The program for a basic algorithm was made with Turbo-C and the subsequent outfile was applied to ANSYS. This standardized model measuring procedure and the program reduce the time required, especially for preprocessing and can be applied to other malocclusions easily.