• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.1
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• pp.141-150
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• 2012

This paper suggests a critical path search algorithm that can easily draw PERT/GANTT chart which manages and plans a project schedule. In order to evaluate a critical path that determines the project schedule, Critical Path Method (CPM) is generally utilized. However, CPM undergoes 5 stages to calculate the critical path for a network diagram that is previously designed according to correlative relationship and execution period of project execution activities. And it may not correctly evaluate $T_E$ (The Earliest Time), since it does not suggest the way how to determine the sequence of the nodes activities that calculate the $T_E$. Also, the sequence of the network diagram activities obtained from CPM cannot be visually represented, and hence Lucko suggested an algorithm which undergoes 9 stages. On the other hand, the suggested algorithm, first of all, decides the sequence in advance, by reallocating the nodes into levels after Breadth-First Search of the network diagram that is previously designed. Next, it randomly chooses nodes of each level and immediately determines the critical path only after calculation of $T_E$. Finally, it enables the representation of the execution sequence of the project activity to be seen precisely visual by means of a small movement of $T_E$ of the nodes that are not belonging to the critical path, on basis of the $T_E$ of the nodes which belong to the critical path. The suggested algorithm has been proved its applicability to 10 real project data. It is able to get the critical path from all the projects, and precisely and visually represented the execution sequence of the activities. Also, this has advantages of, firstly, reducing 5 stages of CPM into 1, simplifying Lucko's 9 stages into 2 stages that are used to clearly express the execution sequence of the activities, and directly converting the representation into PERT/GANTT chart.

• Economic and Environmental Geology
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• v.35 no.3
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• pp.257-271
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• 2002

One of the main interests in relation to heavily contaminated gully-pot sediment in urban area is the short term mobility of heavy metals, which depends on the pH of acidic rainwater and on the buffering effects of carbonate minerals. The buffering effects of carbonates are determined by titration (acid addition). Leaching experiments are carried out in solutions with variable initial HN03 contents for 24h. The gully-pot sediment appears to be predominantly buffered by calcite and dolomite. In case of sediment samples, which highly contain carbonates, pH decreases more slowly with increasing acidity. On the other hand, for the sediment samples, which less contain carbonate minerals, pH rapidly drops until it reaches about 2 then it decreases slowly. The leaching reactions are delayed until more acid is added to compensate for the buffering effects of carbonates. The Zn, Cu, Pb and Mn concentrations of leachate rapidly increase with decreased pH, while Cd, Co, Ni, Cr and Fe dissolutions are very slow and limited. The solubility of heavy metals depends not only on thc pH values of leachatc but also on the speciation in which metals are associated with sediment particles. In slightly to moderately acid conditions, Zn, Cd, Co, Ni and Cu dissolutions become increasingly important. As deduced from leaching runs, the relative mobility of heavy metals at pH of 5 is found to be: Zn > Cd > Co > Ni > Cu » Pb > Cr, suggesting that moderately acid rainwater leach Zn, Cd, Co, Ni and Cu from thc contaminated gully-pot sediment, while Pb and Cr would remain fixed. The buffering effects of Ca- and Mg-carbonates play an important role in delaying as well as limiting the leaching reactions of heavy metals from highly contaminated gully-pot sediment. The extent of such a secondary environmental pollution will thus depends on how well the metals in sediment can be leached by somewhat acidic rain water. Changes in the physicochemical environments may result in the severe environmental pollution of heavy metals. These results are to be taken into account in the management of contaminated sediments during rainstorms.

• The Korean Journal of Archival Studies
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• no.16
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• pp.147-200
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• 2007

Archives provide users with easier and more convenient access to and use of archival data through their Internet websites. Now, archival websites function not only as a tool of information provision or marketing, or as a gateway of Internet-based materials, but also as cyber space for all services of archives, providing users with information and knowledge and direct accessibility to the services in the archives. At present, Korean archives are proceeding with establishing websites or upgrading existing websites, and the use rates and reliability of web services by users are becoming higher. However, although there have been various studies for the evaluation of general websites, few are found with regard to the evaluation of archival websites. It is necessary for archival websites that provide information service to users of every stripe to make more efforts and have more interest in user-centered convenience, right to know, and information provision-centered service. Accordingly, needless to say, it is necessary to study evaluation criteria of websites so that high quality archival websites can be established. With this background, this study establishes evaluation criteria for archival websites, which are appropriate to their objectives and functions and directly evaluates archives, presenting ways to establish and redevelop archival websites. More detailed purposes are as follows: First, analyzes existing theories of evaluation through reviews on previous literature and elicits evaluation criteria for websites, which are appropriate to archives; Second, based on the elicited evaluation criteria for archival websites, examines the current state of domestic archival websites through analytic evaluation; and Third, presents ways to improve archival websites that may be helpful in establishing or improving them in the future. The expectancy effects of this study are as follows: First, it will be helpful when one wishes to identify the current state of archival websites and to improve or redevelop existing websites, or to develop online service through website; Second, it will function as a checklist when a developer who is to establish an archival website wishes to develop evaluation criteria; and Third, it may be used as an inspection tool when an archives contracts out the establishment of its website.

• Korean Journal of Plant Resources
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• v.32 no.2
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• pp.160-169
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• 2019

The this study was carried out to investigate the growth characteristics of wild-simulated ginseng by direct seeding and transplanting cultivation for develop standard cultivation techniques of wild-simulated ginseng. Bonghwa experimental field were confirm to be suitable location environment for cultivation of wild-simulated ginseng. As a result of this study, the germination rate of wild-simulated ginseng was significantly highest when seed size was over 6.5 mm in the spot seeding cultivation. In the case of transplanting, survival rate was significantly increased when the diameter of root was over 10 mm, planting distance was 7 cm, and the thickness of soil covering was less then 2 cm. The result of growth characteristics of wild-simulated ginseng by cultivation type, growth of stem in spot seeding cultivation was showed significantly increased when seed size over 6 mm, seeding number was 3 grains, and the seeding distance was less then 5 cm. Strip seeding cultivation was showed significantly increased in stem and root growth when seeding distance was 30 cm grains and quantity of seeding was less then 23 g. In the case of transplanting cultivation, it's was showed significantly increased in stem growth when diameter of root was over then 10 mm and direction of rhizome was top and bottom. The results of this study was that to clearly establish the techniques of cultivation of managements and it's will be suggest contribute to the industrial activation of wild-simulated ginseng.

• Journal of Ginseng Culture
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• v.1
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• pp.11-27
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• 2019

The Jurchens, the ancestors of the Qing Manchus, had lived scattered in Manchuria and had made their living mostly on ginseng gathering and animal hunting. Their residential areas, rich with deep forest and numerous rivers, provided great habitation for all kinds of flora and fauna, but not so proper for agriculture. Based on their activities of foraging and hunting, the Jurchens developed a unique social organization that was later transformed into the Banner System, the most distinctive Qing military institution. By the sixteenth century, that the external trade brought considerable changes to Jurchen society. A huge amount of foreign silver, imported from Japan and South America to China, first invigorated commercial economy in China proper, and later caused a huge influence on Ming frontier regions, including Manchuria. In the late sixteenth century when the tradition of foraging and hunting encountered with silver economy, the Jurchen tribes became unified after years of competition and transformed themselves into the Manchus to build the Qing empire in 1636. In 1644 the Manchus succeeded in conquering the China Proper and moved into Beijing. Even after that, the Manchu imperial court never forgot the value of Manchurii ginseng; instead, they paid great efforts to monopolize this profitable root. Until the late seventeenth century, the Qing court used the Banner System to manage Manchurian ginseng. The banner soldiers stationed in Manchuria checked unauthorized civilian entrances in this frontier and protected its ginseng producing mountains from the Han Chinese people. All the process of ginseng gathering was managed by the institutions under the direct control of the imperial court, such as the Imperial Household Department, the Butha Ula Office, and the Three Upper Banner in Shengjing. Banner soldiers were dispatched to the given mountains, collect the given amount of ginseng, and send them to the imperial court in Beijing. The state monopoly of ginseng was maintained throughout the eighteenth and nineteenth centuries under the principle that Manchuria and its natural resources should be guarded from civilian encroachment. At the same time, Manchurian ginseng was considered as an important source of state revenue. The imperial court and financial bureau wanted to collect ginseng as much as they needed. By the late seventeenth century as the ginseng management by the banner soldiers failed in securing the ginseng tax, the Qing court began to invite civil merchants to ginseng business. During the eighteenth century the Qing ginseng policy became more dependent on civil merchants, both their money and management. In 1853 the Qing finally ended the ginseng monopoly, but it was before the early eighteenth century that wealthy merchants hired ginseng gatherers and paid ginseng tax to the state. The Qing monopoly of ginseng was in fact maintained by the active participation of civil merchants in the ginseng business.

• Journal of Nutrition and Health
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• v.54 no.3
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• pp.292-304
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• 2021

Purpose: This study investigated the association between the mothers' use of home meal replacement (HMR) in their children's meals and the diet quality of their young children. Methods: Three hundred and thirty-seven mothers with five-year-old kindergartners in Sejong city participated in the survey from June to July 2020. The questionnaire consisted of the status of HMR use in children's meals and questions for assessing the nutrition quotient for preschoolers (NQ-P). The subjects were classified into three groups according to the frequency of HMR use in children's meals: using HMR more than three times a week (high-frequency group; [HG], n = 65), one-two times a week (moderate-frequency group; [MG], n = 145), and less than once a week (low-frequency group; [LG], n = 130). Results: The mothers' mean age was 38.3 years. The average monthly cost of purchasing HMRs was highest at 200,000-300,000 won in HG, 50,000-100,000 won in MG, and less than 50,000 won in LG (p < 0.001). The consumption frequency of processed meats, fast foods, processed beverages, and sweet & fatty snacks was significantly higher in the HG group than the other groups. The mean NQ-P score was 60.5 in HG, 63.0 in MG, and 64.5 in LG, showing a significant difference (p < 0.01). In the sub-score according to the three areas, there were no significant differences in balance and environment among the three groups. In the moderation area, however, the score was 44.1 in HG, 51.3 in MG, and 57.5 in LG Group, showing a significant difference (p < 0.001). Conclusion: The increase in HMR use was related to the decreased diet quality in the overall and moderation areas of children's diet. These results support the importance of nutrition education for mothers, which aims to reduce their children's access and exposure to processed foods, such as HMR.

• 한국사회정책
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• v.20 no.2
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• pp.169-193
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• 2013

This paper examines how a social investment approach can be applied in a comparative analysis of childcare arrangements. We compared changes in Sweden, France, Germany, the UK, Japan and Korea during the 2000s, focusing on four dimensions of social investment: activation, gender equality, quality of care, and the degree of state's intervention in the family. We considered leave systems and the number of children enrolled in formal care and education facilities as indicators for labour market activation. For gender equality, women's position in employment is considered with respect to labour market participation rates, proportion of permanent employment, and wage-sex ratio. Quality of care concerns child-to-staff ratio and care provided with government quality control. The state's intervention was measured as social spending on families as proportions of GDP and total social spending. Our analysis provides empirical evidence that Sweden and France are pioneers in this arena and that the UK, Germany, Korea, and Japan are path-shifters in their care paradigms, albeit to varying degrees. Is the social investment approach an adequate paradigm for care? In a normative sense, this approach has potential. However, the following issues remain unaddressed: gender equality should be achieved through an expansion in good-quality jobs, fathers should be encouraged to take on childcare duties, and families should have universal access to good-quality childcare services controlled by the government.

• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.118-130
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• 2024

Rehabilitation of mining areas can reduce damage to ecosystems. However, the effects of rehabilitation on ecosystem services (ESs) and its contribution to local communities are not well known. Thus, the aims of this study were to clearly identify the ES beneficiaries affected by mining activities, to determine how the beneficiaries profit from surrounding areas in cooperation with local stakeholders, and to manage the rehabilitation areas for the ESs that the beneficiaries want. This study chose 18 ESs (4 provisioning, 7 regulating, 5 cultural, and 2 habitat services) based on The Economics of Ecosystems and Biodiversity. A semi-structured questionnaire survey using an 11-point Likert scale was conducted among 87 community residents to investigate social awareness and identify key ESs. The survey results from two local communities showed high awareness and demands mainly on cultural (mental and physical health, aesthetic appreciation, and recreation) and regulating services (local climate and air quality, and moderation of extreme events). These services were related to the daily lives of residents in local communities, provided positive benefits, and potentially improved the residents' future livelihoods. However, the average questionnaire scores were limited to 6-7 points, indicating that the benefits to local communities were meager. The residents' awareness of provisioning service was negative, even if it provided goods and profit opportunities. This indicated a disconnection between local communities and provisioning services due to forest rehabilitation that did not consider local communities that traditionally relied on specific provisioning services before the onset of mining activities. Future forest rehabilitation in abandoned mine areas must consider the welfare of local communities for sustainable use of rehabilitated forests and enhancing ESs. In this study, only a qualitative evaluation based on frequency analyses was conducted. The quantification and valuation of key ESs are warranted in the future to promote ESs from forest rehabilitation in abandoned mine areas. The study results would be useful for developing site-specific ES promotion strategies for reforesting mine areas.

• Clinical and Experimental Pediatrics
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• v.52 no.10
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• pp.1090-1102
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• 2009

Purpose:To evaluate current feeding practices and maternal nutritional knowledge on complementary feeding. Methods:Mothers of babies aged 9-15 months who visited pediatric clinics of 14 general hospitals between September and December 2008 were asked to fill questionnaires. Data from 1,078 questionnaires were analyzed. Results:Complementary food was introduced at 4-7 months in 89% of babies. Home-made rice gruel was the first complementary food in 93% cases. Spoons were used for initial feeding in 97% cases. At 6-7 months, <50% of babies were fed meat (beef, 43%). Less than 12-month-old babies were fed salty foods such as salted laver (35%) or bean-paste soup (51%) and cow's milk (11%). The following were the maternal sources of information on complementary feeding: books/magazines (58%), friends (30%), internet web sites (29%), relatives (14%), and hospitals (4%). Compared to the 1993 survey, the incidence of complementary food introduction before 4 months (0.4% vs. 21%) and initial use of commercial food (7% vs. 39%) had decreased. Moreover, spoons were increasingly used for initial feeding (97% vs. 57%). The average maternal nutritional knowledge score was 7.5/10. Less percentage of mothers agreed with the following suggestions: bottle formula weaning before 15-18 months (68%), no commercial baby drinks as complementary food (67%), considering formula (or cow's milk) better than soy milk (65%), and feeding minced meat from 6-7 months (57%). Conclusion:Complementary feeding practices have considerably improved since the last decade. Pediatricians should advise timely introduction of appropriate complementary foods and monitor diverse information sources on complementary feeding.

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.203-209
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• 2020

The purpose of this study is to assess the mechanical stability and alignment of the patient positioning system (PPS) of Leksell Gamma Knife Perfexion(LGK PFX). The alignment of the PPS of the LGK PFX was evaluated through measurements of the deviation of the coincidence of the Radiological Focus Point(RFP) and the PPS Calibration Center Point(CCP) applying different weights on the couch(0, 50, 60, 70, 80, and 90 kg). In measurements, a service diode test tool with three diode detectors being used biannually at the time of the routine preventive maintenance was used. The test conducted with varying weights on the PPS using the service diode test tool measured the radial deviations for all three collimators 4, 8, and 16 mm and also for three different positions of the PPS. In order to evaluate the alignment of the PPS, the radial deviations of the correspondence of the radiation focus and the LGK calibration center point of multiple beams were averaged using the calibrated service diode test tool at three university hospitals in Busan and Gyeongnam. Looking at the center diode for all collimators 4, 8, and 16 mm without weight on the PPS, and examining the short and long diodes for the 4 mm collimator, the means of the validation difference, i.e., the radial deviation for the setting of 4, 8, and 16 mm collimators for the center diode were respectively measured to 0.058 ± 0.023, 0.079 ± 0.023, and 0.097 ± 0.049 mm, and when the 4 mm collimator was applied to the center diode, the short diode, and the long diode, the average of the radial deviation was respectively 0.058 ± 0.023, 0.078 ± 0.01 and 0.070 ± 0.023 mm. The average of the radial deviations when irradiating 8 and 16 mm collimators on short and long diodes without weight are measured to 0.07 ± 0.003(8 mm sd), 0.153 ± 0.002 mm(16 mm sd) and 0.031 ± 0.014(8 mm ld), 0.175 ± 0.01 mm(16 mm ld) respectively. When various weights of 50 to 90 kg are placed on the PPS, the average of radial deviation when irradiated to the center diode for 4, 8, and 16 mm is 0.061 ± 0.041 to 0.075 ± 0.015, 0.023 ± 0.004 to 0.034 ± 0.003, and 0.158 ± 0.08 to 0.17 ± 0.043 mm, respectively. In addition, in the same situation, when the short diode for 4, 8, and 16 mm was irradiated, the averages of radial deviations were 0.063 ± 0.024 to 0.07 ± 0.017, 0.037 ± 0.006 to 0.059 ± 0.001, and 0.154 ± 0.03 to 0.165 ± 0.07 mm, respectively. In addition, when irradiated on long diode for 4, 8, and 16 mm, the averages of radial deviations were measured to be 0.102 ± 0.029 to 0.124 ± 0.036, 0.035 ± 0.004 to 0.054 ± 0.02, and 0.183 ± 0.092 to 0.202 ± 0.012 mm, respectively. It was confirmed that all the verification results performed were in accordance with the manufacturer's allowable deviation criteria. It was found that weight dependence was negligible as a result of measuring the alignment according to various weights placed on the PPS that mimics the actual treatment environment. In particular, no further adjustment or recalibration of the PPS was required during the verification. It has been confirmed that the verification test of the PPS according to various weights is suitable for normal Quality Assurance of LGK PFX.