• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.592-599
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• 2019

This study aimed to develop an equation for estimating stem volume for Larix kaempferiin South Korea using independent variables, diameter at breast height (DBH), and height as being closely associated with stem volume. Analysis was conducted on the growth performance of 2,840 Larix kaempferi samples across South Korea after felling them and gleaning diameter data according to both stem height and stem analyses. In order to test the fitness of six different stem taper equations, empirical assessment was conducted for fitness index (FI), bias, mean, and absolute deviation (MAD), and coefficient variation (%CV). The two selectedmodels found to be optimal were the following: model one (V=a+bDBH²), established by employing DBH only; and model four (V=a+bDBH²H), established by utilizing DBH and height, respectively. The findings of non-linear regression indicated statistical significance (p < 0.05) in a and b, which were the coefficients for the intercepts and slopes of the models. The FI of the models ranged between 94% and 99%, and the bias was close to zero, while MAD ranged from 0.01 to 0.05, and %CV from 5.97 to 14.43, indicating a high level of fitness. Thus, using the suggested models, the basic information necessary for forest management was obtained, and an estimation of the stem volume was effected without delay soon after effecting DBH and height measurements.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.480-487
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• 2006

This study was conducted to improve the germination percent and germination speed by seed priming using polyethylene glycol (PEG) 8,000 solution on Acer mono seed because it has low and irregular germination characteristics. Seed priming was carried out under 0, -0.25, -0.5, -1.0 and -2.0 MPa of water potential at $20^{\circ}C$ for 3 days. Primed seeds showed higher percent germination, germination speed, mean germination time (MGT) and germination performance index (GPI) than unprimed seeds. Especially, primed seed with -2.0 MPa of water potential had the highest germination properties. And primed seeds had a lower dormancy than the unprimed seeds. Relative growth rate and T/R ratio of seedling from primed seeds were measured to survey the effect of seed priming on the seedling vigor as well as seed germination. The seedlings from primed seeds at -2.0 MPa of water potential showed the highest relative growth rates of height and root collar diameter, however, the lowest value in T/R ratio. This study suggested that seeds priming at -2.0 MPa of water potential under $20^{\circ}C$ for 3 days enhanced not only the percent germination, germination speed, MGT and GPI but also the vigor and growth of seedlings in Acer mono.

• Journal of the Ergonomics Society of Korea
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• v.34 no.1
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• pp.29-43
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• 2015

Objective: The aim of this study is to develop management guidelines and a procedure for an anthropometric suitability assessment of the main control room (MCR) in nuclear power plants (NPPs). Background: The condition of the MCR should be suitable for the work crews in NPPs. The suitability of the MCR depends closely on the anthropometric dimensions and ergonomic factors of the users. In particular, the MCR workspace design in NPPs is important due to the close relationship with operating crews and their work failures. Many documents and criteria have recommended that anthropometry dimensions and their studies are one of the foremost processes of the MCR design in NPPs. If these factors are not properly considered, users can feel burdened about their work and the human errors that might occur. Method: The procedure for the anthropometric suitability assessment consists of 5 phases: 1) selection of the anthropometric suitability evaluation dimensions, 2) establishment of a measurement method according to the evaluation dimensions, 3) establishment of criteria for suitability evaluation dimensions, 4) establishment of rating scale and improvement methods according to the evaluation dimensions, and 5) assessment of the final grade for evaluation dimensions. The management guidelines for an anthropometric suitability assessment were completed using 10 factors: 1) director, 2) subject, 3) evaluation period, 4) measurement method and criteria, 5) selection of equipment, 6) measurement and evaluation, 7) suitability evaluation, 8) data sharing, 9) data storage, and 10) management according to the suitability grade. Results: We propose a set of 17 anthropometric dimensions for the size, cognition/perception action/behavior, and their relationships with human errors regarding the MCR design variables through a case study. The 17 selected dimensions are height, sitting height, eye height from floor, eye height above seat, arm length, functional reach, extended functional reach, radius reach, visual field, peripheral perception, hyperopia/myopia/astigmatism, color blindness, auditory acuity, finger dexterity, hand function, body angle, and manual muscle test. We proposed criteria on these 17 anthropometric dimensions for a suitability evaluation and suggested an improvement method according to the evaluation dimensions. Conclusion: The results of this study can improve the human performance of the crew in an MCR. These management guidelines and a procedure for an anthropometric suitability assessment will be able to prevent human errors due to inadequate anthropometric dimensions. Application: The proposed set of anthropometric dimensions can be integrated into a managerial index for the anthropometric suitability of the operating crews for more careful countermeasures to human errors in NPPs.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.14-23
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• 2012

This study was performed to investigate the effects of storage, temperature, and pre-treatments on the germination of Melia azedarach seeds collected from Buan, Jeonju, and Jeju provenance. M. azedarach seeds stored with or without pericarp in the ground, which collected from Buan provenance evidenced the highest germination percentage (PG, %) and the shortest time to first germination (days). The seeds collected from Jeonju and Jeju provenance were placed at both six continuous temperatures (15, 20, 25, 30, 35, and $40^{\circ}C$) and two alternating temperatures ($20{\leftrightarrow}30^{\circ}C$ and $25{\leftrightarrow}35^{\circ}C$) for seed incubation. The results showed a significant effect for temperature of seed incubation. The seeds incubated at $35^{\circ}C$ had the highest PG among the continuous temperatures and germinated significantly more at the two alternating temperatures than at $35^{\circ}C$. Concerning mean germination time (MGT), the seeds incubated at $35^{\circ}C$ evidenced the shortest germinations among the continuous temperatures while those at the alternating temperatures germinated for a shorter period than those at $35^{\circ}C$. The germination rate (GR) and germination performance index (GPI) were similar to PG. The seeds collected from Jeonju provenance were treated using five pre-sowing treatments (scarification, scarifcation+$GA_3$, scarification+$KNO_3$, $GA_3$, and $KNO_3$) prior to the germination experiments. Compared with the intact seeds (control), most of the pre-treatments were significantly (especially scarification+$GA_3$ 100 ppm and scarification+$KNO_3$ 1.0%) higher in PG, GR, and GPI, as well as shorter in MGT.

• Journal of Korea Water Resources Association
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• v.53 no.11
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• pp.1025-1037
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• 2020

This study attempted to evaluate the spatial characteristics and applicability of the predicted ensemble rainfall data used for heavy rain alarms. Limited area ENsemble prediction System (LENS) has 13 rainfall ensemble members, so it is possible to use a probabilistic method in issuing heavy rain warnings. However, the accessibility of LENS data is very low, so studies on the applicability of rainfall prediction data are insufficient. In this study, the evaluation index was calculated by comparing one point value and the area average value with the observed value according to the heavy rain warning system used for each administrative district. In addition, the accuracy of each ensemble member according to the LENS issuance time was evaluated. LENS showed the uncertainty of over or under prediction by member. Area-based prediction showed higher predictability than point-based prediction. In addition, the LENS data that predicts the upcoming 72-hour rainfall showed good predictive performance for rainfall events that may have an impact on a water disaster. In the future, the predicted rainfall data from LENS are expected to be used as basic data to prepare for floods in administrative districts or watersheds.

• The Korean Journal of Emergency Medical Services
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• v.20 no.2
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• pp.7-19
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• 2016

Purpose: To investigate the effect of early hypothermia on post-resuscitation myocardial recovery and survival time after cardiac arrest and resuscitation in a rat model of myocardial infarction(MI). Methods: Thoracotomies were performed in 10 male Sprague Dawley rats weighing 450-455g. Myocardial infarction was induced by ligation of the left anterior descending coronary artery. Ninety minutes after arterial ligation, ventricular fibrillation was induced, cardiopulmonary resuscitation was subsequently performed before defibrillation was attempted. Animals were randomized to control group and experimental group(acute MI-normothermia)($32^{\circ}C$ for 4 hours). Duration of survival was recorded. Myocardial functions, including cardiac output, left ventricular ejection fraction, and myocardial performance index were measured using echocardiography. Results: Myocardial function was significantly better in hypothermia group than the control group during the first 4 hours post-resuscitation. The survival time of the experimental group was greater than that of the control group(p<.050). Conclusion: This study suggests that early hypothermia can attenuate post-resuscitation myocardial dysfunction after acute myocardial function, and may be a useful strategy in post-resuscitation care.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.1
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• pp.90-103
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• 2017

This study carried out field evaluation by experts, monitoring by the public, and visitor satisfaction survey for 88 sites by using cultural property projects that received support from "SaengSaeng Cultural Property"in 2016. The result of the comprehensive evaluation was 'good', the part of planning, outcome, annual special index were 'good', field operation and performance were 'normal'. The field evaluation was rated as 'normal' by experts, monitoring by the public was 'good', and visitor satisfaction survey was also 'good'. The advantages of the project were as follows; increased enjoyment of local cultural assets, utilization of historical and cultural heritage as tourism, expansion of local participation and cooperation. On the other hand, the disadvantages were as follows; shortage of promotion to other local people, deterioration of program's quality, insufficient materials for explanation of cultural assets, insufficient program for staying. We suggested measures to develop the project as follows; developing paid contents in order to secure sustainability, connection with other programs, developing representative program and brand, improvement of environment to participate, strengthening of role for experienced local organization, utilization of local artists and volunteers, exchange between local organization, promoting by government organization, managing existing visitors, establishing of strategy for promotion, improvement of monitoring by the public, strengthening of reflection of visitor's opinions, consulting for each programs.

• Journal of KIISE:Databases
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• v.29 no.5
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• pp.367-380
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• 2002

Due to recent increase in applications requiring huge amount of data such as spatial data analysis and image analysis, clustering on large databases has been actively studied. In a hierarchical clustering method, a tree representing hierarchical decomposition of the database is first created, and then, used for efficient clustering. Existing hierarchical clustering methods mainly adopted the bottom-up approach, which creates a tree from the bottom to the topmost level of the hierarchy. These bottom-up methods require at least one scan over the entire database in order to build the tree and need to search most nodes of the tree since the clustering algorithm starts from the leaf level. In this paper, we propose a novel top-down hierarchical clustering method that uses multidimensional indexes that are already maintained in most database applications. Generally, multidimensional indexes have the clustering property storing similar objects in the same (or adjacent) data pares. Using this property we can find adjacent objects without calculating distances among them. We first formally define the cluster based on the density of objects. For the definition, we propose the concept of the region contrast partition based on the density of the region. To speed up the clustering algorithm, we use the branch-and-bound algorithm. We propose the bounds and formally prove their correctness. Experimental results show that the proposed method is at least as effective in quality of clustering as BIRCH, a bottom-up hierarchical clustering method, while reducing the number of page accesses by up to 26～187 times depending on the size of the database. As a result, we believe that the proposed method significantly improves the clustering performance in large databases and is practically usable in various database applications.

• Archives of design research
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• v.17 no.3
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• pp.111-122
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• 2004

The purpose of this study are two the first is to identify the positioning of product design and analyze its functional relationship with product development, manufacturing, marketing and sales in the comprehensive competitiveness evaluation model ; and the second is to estimate the determinants of QCI(quality competitiveness index), analyze the impact of product design on QCI, and compare the aforementioned results for the seven industrial sectors and the five product patterns. For this empirical analysis, this study surveyed 400 Korean manufacturing firms during August-October 2003. The major empirical findings are summarized as follows : First, the hypothesis on the positive effect of product design on QCI is accepted at a highly significant level (p < 0.001) for all : the manufacturing sector, seven industrial sectors, and five product categories. Second, the correlation analysis and factor analysis lead to the result that the effect of product design on QCI is estimated to be relatively very low, in comparison to those of product functionality and basic performance on QCI. These findings imply that Korean manufacturing sector has been still in the prematured stage at which product design has not played an important role yet. This study concludes that product design in line with other functions (product development, manufacturing, marketing, and sales) should make a good contribution to the improvement of QCI in the future.

• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.44-49
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• 2008

The purpose of this study is to investigate the current status, including the maintenance problems and removal efficiency, of small sewage treatment facilities in Chung-nam province(Asan, Buyeo, and Gongju city). Our results showed that inflow water quality of Asan city was 19.1 mg/L of BOD, 29.0 mg/L of COD, 13.4 mg/L of T-N and 1.5 mg/L of T-P, respectively, which was much higher than any other site. Among the factors known to be an important index of water quality, the SS and BOD removal efficiency was about 70% and 50% respectively. However, the nitrogen removal efficiency was less than 10%. The total removal efficiency of pollutant was 71.1% of SS, 52.6% of BOD, 46.2% of COD, 9.2% of T-P and 4.6% of T-N respectively. Therefore nitrogen removal processes are required to prevent serious eutrophication of small river. Removal efficiency for BOD and SS of high-efficient sewage treatment facilities (STFs) and contact oxidation process was much higher than another process. Performance of these sewage treatment facilities(STFs) is not optimal due to ineffective planning for the inflow water quality. To improve these facilities, it is proposed that a technical expert analysis of water quality at these facilities is periodically required.