• Proceedings of the SAREK Conference
• /
• 2008.11a
• /
• pp.493-498
• /
• 2008

Particles or deposit formed by corrosion of the pipe material bring about bad influences on the heating systems with inconvenience, energy loss and so on. In order to obtain the non-corrosive environments, the circulation hot water should properly be treated in several ways to satisfy one or more conditions of the followings: suitable pH-level, low hardness, low oxygen content, low conductivity, low level of chlorides and sulphur compounds and low level of solid particles. This experimental study was carried out to develope the new guidelines on the optimal water quality and directions for water quality management in heating systems. As results, it was recommended that the heating water be maintained pH-level not less than 8, hardness contents as $CaCO_3$ no more than 50 mg/L, turbidity no more than 10 NTU and T-Fe contents 1 mg/L below.

• Journal of the Korea Society of Computer and Information
• /
• v.3 no.4
• /
• pp.49-54
• /
• 1998

AS it takes a considerable time for database operations for processing the condition part of active rule, the operations have an important effect on the efficiency of active database system. The processing time of operations should be minimized in order to improve the efficiency of system. The previous works are limited to basic database operations and the partial aggregate functions. In this paper, the processing technique using the structuralization and the state table of relations is suggested. The processing time for basic database operations can be reduced with the structuralization of relations to classification tree and the introduction of deletion information table. With the introduction of binary search tree and relation state table, the aggregate function which has a big of processing cost can be processed effectively and the function of the active database system can be maximized.

• Water for future
• /
• v.14 no.4
• /
• pp.27-34
• /
• 1981

The design flow of the urban strom drainage systems has been assessed largely on a basis of empirical relations between rainfall and runoff, and the rational formula has been widely used for the cities in our country. In order to estimate it more accurately, the urban runoff simulation model based on the RRl method has been developed and applied to the sample basin in this study. The rainfall hyetograph of the design stromfor the design flow has been obtained by the determination of the total rainfall and the temporal distributions of that rainfall. The total rainfall has been assessed from the empirical formula of rainfall intensity and the temporal distribution of that rainfall determined on the basis of Huff's method from the historical rainfall data of the basin. The virtual inflow hydrograph to each inlet of the basin has been constructed by computing the series of discharges in each time increment, using design strom hyetograph and time-area diagram. The actual runoff hydrograph at the basin outlet has been computed from the virtual inflow hydrographs by developing a relations between discharge and storage for the watershed. The discharge data for verification of the simulated runoff hydrograph are not available in the sample basin and so the sensitivity analysis of the simulation model has not been possible. The peak discharge for the design of drainage systems has been estimated from the computed runoff hydrograph at the basin outlet and compared to thatl obtained form the rational formula.

• Research in Community and Public Health Nursing
• /
• v.20 no.2
• /
• pp.143-151
• /
• 2009

Purpose: This study was to investigate the relations and odds ratio between hs-CRP and the risk factors of metabolic syndrome according to glucose intolerance and diabetes among the residents of a rural community. Methods: The subjects include 1,968 adults aged from 40 to 70 who were divided into four groups and a diabetes group according to glucose intolerance to compare the relations and risk ratio between hs-CRP and the risk factors of metabolic syndrome. Results: The results reveal that the greater the subjects' glucose intolerance was, the higher their hs-CRP became and the more risk factors of metabolic syndrome they had. The impaired glucose tolerance group showed 1.7 times higher blood pressure than the control group. The diabetes group showed a high odds ratio with 2.3 times higher blood pressure, 2.2 times higher abdominal obesity, and 2.4 times higherW/Ht than the control group. And the odds ratio increased significantly by 1.7 times in the hs-CRP intermediate risk group and 2.5 times in the high risk group compared with the control group. Conclusion: Considering the study results, it is very important to monitor abdominal obesity, blood pressure and the intermediate and high risk group of hs-CRP in order to reduce the contraction of cardiovascular diseases.

• Tunnel and Underground Space
• /
• v.20 no.2
• /
• pp.112-118
• /
• 2010

Before blasts that can have direct impacts on human bodies or structures, it is necessary to assess impacts of ground vibration. Therefore, frequency has been recognized as an important factor in order to assess impact on ground vibration and damages. There have been many studies on impacts of frequency. But, there have been no studies on relations between vibration and frequency according to delay time difference. In this study, we examined the relations between delay time difference and frequency according to each frequency with which reinforcement and destructive intervention repeat through delay time difference obtained using superposition modeling of single hole blasting waveform based on the theory of time difference developed by Langefors.

• Journal of Family Relations
• /
• v.20 no.4
• /
• pp.131-156
• /
• 2016

Objective: This study aimed to examine parenting education participation of Korean mothers in the transition to parenthood and its related variables. Method: A study sample was composed of 870 mothers whose first child was younger than one-year old from the Panel Study on Korean Children in 2008(mean age=30.1, SD = 3.69). The descriptive statistics of parenting education participation were presented. In addition, negative binomial and logistic regression models were used in Stata13 in order to examine the variables related to parenting education participation of mothers in the transition to parenthood. Results: Approximately 82% of the mothers reported that they had participated in at least one parenting education program. Further, mother's educational level, monthly household income, mother's working experience, and community type generally predicted parenting education participation of mothers. However, the effects of these variables varied by the subjects and the providing institutions. Conclusion: This study provides the overall picture of parenting education participation of Korean mothers in the transition to parenthood and its related variables. The findings can be utilized to plan more effective parenting education programs for new parents.

• Asia-Pacific Journal of Business
• /
• v.11 no.3
• /
• pp.107-122
• /
• 2020

Purpose - This paper investigates the relations among exploratory and exploitative supply chain management practices, competitive advantage, and firm performance. Design/methodology/approach - This study takes a hypothesis-generating study to capture the tradeoffs between exploration and exploitation and develops some hypotheses which involve the relations among SCM practices, competitive advantage, and short-term and long-term performance. Findings - Exploitative SCM practices have more positive effects on short-term performance rather than long-term performance, whereas exploratory SCM activities affect long-term performance. Further competitive strategy, environmental dynamism, and organizational slack moderates the relationship between SCM and performance. Exploitative SCM is more desirable when a firm uses low cost strategy, lacks slack resources, and faces stable environment, while exploratory SCM is more effective when a firm employs differentiation strategy, has slack resources, and confront dynamic environment. Research implications or Originality - In order to understand the performance effects of a variety of SCM practices, we should distinguish between exploitative and exploratory SCM activities. Further the relationship between SCM and performance may differ depending upon some contingent variables such as external environment, competitive strategy and organizational slack.

• Korean Journal of Remote Sensing
• /
• v.35 no.1
• /
• pp.163-177
• /
• 2019

As inter-Korean relations progress, the issue of natural disasters which could directly affect the lives of the people in both Koreas, has not yet been discussed. Considering the current status of inter-Korean relations and the ongoing disaster-related damage in North Korea, it is imperative to establish a technical plan at the pan-governmental level to reduce the damage from natural disasters. The purpose of this study is to secure the Korea Peninsula against natural disasters by organizing South Korea's science and technologies related to natural disasters in order to reduce the damage, and to evaluate the applicability of said technologies. The situation of natural disasters in North Korea for 17 years has been summarized and reclassified based on eight types of natural disasters. Technologies related to natural disasters in South Korea were also investigated and reclassified. Based on the data, a priority evaluation was performed and the prioritization of technology application for each natural disaster type in North Korea was calculated through a quadrant analysis. As a result, the three major categories of high-priority technologies were classified as natural disaster monitoring with remote sensing and spatial information technology, construction of research basis and database based on geographic information system (GIS) and integrated management of complex natural disasters.

• Journal of the Korea Convergence Society
• /
• v.12 no.9
• /
• pp.83-91
• /
• 2021

This study examined the effects of message framing (advertising attitude and brand attitude) to Chinese consumers in order to establish guidelines for digital content development reflecting the Korean Wave in China. Specifically, in positive message framing, Southerners with low neuroticism due to their personality characteristics show a greater advertising effect than Northerners with high neuroticism. Based on these results, this study provides a theoretical basis for establishing the direction of Korean Wave digital content production according to differences in residential areas reflecting personality in China.

• Journal of Family Relations
• /
• v.22 no.1
• /
• pp.41-62
• /
• 2017

Objectives: The purpose of this study was to examine the relationship between parenting attitudes and martial intimacy and was to examine the mediating effect of marital communication in order to provide effective help to improve marital intimacy of middle-aged married women who have difficulty in marital relationship. Method: The subjects of this study were 229 married women aged 40-59. Statistical analysis of this study was performed using the SPSS 18.0 program. Results: The results of this study are summarized as follows. First, Pearson 's correlation analysis was conducted to investigate the relationship between parenting attitude, marital intimacy, and marital communication and the results were statistically significant. Second, the three - step hierarchical regression analysis proposed by Baron and Kenny (1986) was conducted to examine the mediating effect of marital communication on the relationship between parenting attitudes and marital intimacy, it was confirmed that marital communication was partially mediated between parenting attitudes and marital intimacy. Conclusion: This study is meaningful in that it was confirmed that marital communication was partially mediated between parenting attitudes and marital intimacy.