• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.14 no.12
• /
• pp.1102-1139
• /
• 2002

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 2000 and 2001 has been done. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environment. The conclusions are as follows. (1) Most of fundamental studies on fluid flow were related with heat transportation of facilities. Drop formation and rivulet flow on solid surfaces were interesting topics related with condensation augmentation. Research on micro environment considering flow, heat, humidity was also interesting for comfortable living environment. It can be extended considering biological aspects. Development of fans and blowers of high performance and low noise were continuing topics. Well developed CFD technologies were widely applied for developing facilities and their systems. (2) Most of papers related with heat transfer analysis and heat exchanger shows dealt with convection, evaporation, and channel flow for the design application of heat exchanger. The numerical heat transfer simulation studies have been peformed and reported to show heat transfer characteristics. Experimental as well as numerical studies on heat exchanger were reported, while not many papers are available for the system analysis including heat exchanger. (3) A review of the recent studies on heat pump system shows that performance analysis and control of heat pump have been peformed by various simulations and experiments. The research papers on multi-type heat pump system increased significantly. The studies on heat pipe have been examined experimently for change of working characteristics and strut lure. Research on the phase change has been carried out steadily and operation strategies of encapsulated ice storage tank are reported experimentally in several papers. (4) A review of recent studies on refrigeration/air conditioning system have focused on the system performance and efficiency for new alternative refrigerants. Evaporation and condensation heat transfer characteristics are investigated for tube shapes and new alternative refrigerants. Studies on components of refrigeration/air conditioning system are carried to examine efficiency for various compressors and performance of new expansion devices. In addition to thermophysical properties of refrigerant mixtures, studies on new refrigerants are also carried out, however research works on two-phase flow seemed to be insufficient. (5) A review of the recent studies on absorption cooling system indicates that heat and mass transfer phenomena have been investigated to improve absorber performance. Various experimental data have been presented and several simulation models have been proposed. A review of the recent studies on duct and ventilation shows that ventilation indices have been proposed to quantify the ventilation performance in buildings and tunnels. Main efforts have been focused on the applications of ventilation effectiveness in practice, either numerically using computational fluid dynamics or experimentally using tracer gas techniques. (6) Based on a review of recent studies on indoor thermal environment and building service systems, research issues have mainly focused on many innovative ideas such as underfloor air-conditioning system, personal environmental modules, radiant floor cooling and etc. Also, the new approaches for minimizing energy consumption as well as improving indoor environmental conditions through predictive control of HVAC systems, various activities of building energy management and cost-benefit analysis for economic evaluation were highlighted.

• Journal of Intelligence and Information Systems
• /
• v.20 no.4
• /
• pp.1-23
• /
• 2014

Market forecasting aims to estimate the sales volume of a product or service that is sold to consumers for a specific selling period. From the perspective of the enterprise, accurate market forecasting assists in determining the timing of new product introduction, product design, and establishing production plans and marketing strategies that enable a more efficient decision-making process. Moreover, accurate market forecasting enables governments to efficiently establish a national budget organization. This study aims to generate a market growth curve for ICT (information and communication technology) goods using past time series data; categorize products showing similar growth patterns; understand markets in the industry; and forecast the future outlook of such products. This study suggests the useful and meaningful process (or methodology) to identify the market growth pattern with quantitative growth model and data mining algorithm. The study employs the following methodology. At the first stage, past time series data are collected based on the target products or services of categorized industry. The data, such as the volume of sales and domestic consumption for a specific product or service, are collected from the relevant government ministry, the National Statistical Office, and other relevant government organizations. For collected data that may not be analyzed due to the lack of past data and the alteration of code names, data pre-processing work should be performed. At the second stage of this process, an optimal model for market forecasting should be selected. This model can be varied on the basis of the characteristics of each categorized industry. As this study is focused on the ICT industry, which has more frequent new technology appearances resulting in changes of the market structure, Logistic model, Gompertz model, and Bass model are selected. A hybrid model that combines different models can also be considered. The hybrid model considered for use in this study analyzes the size of the market potential through the Logistic and Gompertz models, and then the figures are used for the Bass model. The third stage of this process is to evaluate which model most accurately explains the data. In order to do this, the parameter should be estimated on the basis of the collected past time series data to generate the models' predictive value and calculate the root-mean squared error (RMSE). The model that shows the lowest average RMSE value for every product type is considered as the best model. At the fourth stage of this process, based on the estimated parameter value generated by the best model, a market growth pattern map is constructed with self-organizing map algorithm. A self-organizing map is learning with market pattern parameters for all products or services as input data, and the products or services are organized into an $N{\times}N$ map. The number of clusters increase from 2 to M, depending on the characteristics of the nodes on the map. The clusters are divided into zones, and the clusters with the ability to provide the most meaningful explanation are selected. Based on the final selection of clusters, the boundaries between the nodes are selected and, ultimately, the market growth pattern map is completed. The last step is to determine the final characteristics of the clusters as well as the market growth curve. The average of the market growth pattern parameters in the clusters is taken to be a representative figure. Using this figure, a growth curve is drawn for each cluster, and their characteristics are analyzed. Also, taking into consideration the product types in each cluster, their characteristics can be qualitatively generated. We expect that the process and system that this paper suggests can be used as a tool for forecasting demand in the ICT and other industries.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.36 no.3
• /
• pp.63-74
• /
• 2008

With the awareness that Sinyeongwol Sipgyeong(ten scenic spots in Yeongwol) were designed too hastily and only for PR purposes after the change in the tourism environment, this paper indicates that most tourism and culture sources in Yeongwol are related to King Danjong, the sixth king of the Joseon Dynasty. This study proposes a 'Storytelling Plan' for the landscape content called 'Cultural Landscapes - Yeongwol Palgyeong(eight scenic spots in Yeongwol)' after reviewing types and content of Yeongwol Palgyeong through the halo effect of the well-known sad history of King Danjong and the cultural value of Yeongwol. The significance of the unity of the historic site and neighboring landscape is focused on by investigating the anaphoric relations between cultural landscape texts('Yeongwol Palgyeong') and historic content(the sad history of King Danjong). For this, the cultural lnddscape of Yeongwol has been framed and layered to make spatial texts. To emphasize the 'Telling' as well as the 'Story,' interesting episodes have been reviewed to discover a motive. To diversify the 'Telling' methods, absorptive landscape factors have been classified as 'Place,' 'Object' and 'Visual Point.' In addition the storytelling of Yeongwol Palgyeong was examined in consideration of the story and background of 'Yeongwol Palgyeong - Sad Story of King Danjong' and the interaction of a variety of cultural content by suggesting micro-content such as infotainment and edutainment as absorptive landscape factors. In order to make the storytelling plan available in practice as an alternative plan for Yeongwol Tourism, a visual point should be properly set to make the landscape look sufficiently dynamic. In addition, real landscape routes and narration scenarios should be prepared as well. Professional landscape interpreters who are well informed of the natural features of Yeongwol and the history of King Danjong should be brought into the project, and Internet and digital technology-based strategies should be developed.

• Progress in Medical Physics
• /
• v.19 no.4
• /
• pp.276-284
• /
• 2008

A computed tomography (CT) is a powerful system for the effectively fast and accurate diagnosis. The CT system, therefore, has used substantially and developed for improving the performance over the past decade, resulting in growing concerns over the radiation dose from the CT. Advanced CT techniques, such as a multidetector row CT scanner and dual energy or dual source CT, have led to new clinical applications that could result in further increases of radiation does for both patients and workers. The objective of this study was to review the international guidelines of the shielding requirements for a CT facility required for a new installation or when modifying an existing one. We used Google Search Engine to search the following keywords: computed tomography, CT regulation or shield or protection, dual energy or dual source CT, multidetector CT, CT radiation protection, and regulatory or legislation or regulation CT. In addition, we searched some special websites, that were provided for sources of radiation protection, shielding, and regulation, RSNA, AAPM, FDA, NIH, RCR, ICRP, IRPA, ICRP, IAEA, WHO (See in Table 1 for full explanations of the abbreviations). We finally summarized results of the investigated materials for each country. The shielding requirement of the CT room design was very well documented in the countries of Canada, United States of America, and United Kingdom. The wall thickness of the CT room could be obtained by the iso-exposure contour or the point source method. Most of documents provided by international organizations were explained in importance of radiation reduction in patients and workers. However, there were no directly-related documents of shielding and patient exposure dose for the dual energy CT system. Based international guidelines, the guideline of the CT room shielding and radiation reduction in patients and workers should be specified for all kinds of CT systems, included in the dual energy CT. We proposed some possible strategies in this paper.

• Korean Journal of Environmental Biology
• /
• v.36 no.1
• /
• pp.33-42
• /
• 2018

The tropical peatlands have been deforested and converted to agricultural and plantation areas in Indonesia. To manage water levels and increase the overall productivity of crops, canals have been constructed in tropical peatlands. The canals destructed the structure of the tropical peatlands, and increased the subsidence and fire hazard risks in the region. The Indonesian government enacted regulations and a moratorium on tropical peatlands, in order to reduce degradation. A practical method under the regulations of rewetting tropical peatlands was to permit a canal blocking. In this study, four canal blocking projects were investigated regarding their planning, construction priority, design, building material, construction, monitoring, time and costs associated with the canal blockings. In the protected areas, regulations restricted the development of the tropical peatlands areas that were noted as deeper than 3 m, and the administration stopped issuing new concessions for future work projects for this noted criteria of land use. A noted purpose of canal blockings in these areas was to effectuate the restoration of the lands in the region. The main considerations of the restoration efforts were to maintain a durability of the blockings, and to encourage the participation of the area stakeholders. In the case of a concession area, regulations were set into place to restrict clear-cutting and shifting cultivation, and to maintain groundwater level in the tropical peatland. The most significant priorities identified in the canal blocking project were the efficiency and cost-effectiveness of the project. Nevertheless, the drainage of tropical peatlands has been continued. On the basis of a literature review on regulations and rewetting methods in tropical peatlands of Indonesia, we discussed the improvements of the regulations, and adequate canal blockings to serve the function to rewet the tropical peatlands in Indonesia. Our results would help establishing an adequate direction and recommended guideline on viable rewetting methods for the restoration of drained tropical peatlands in Southeast Asia.

• Journal of Intelligence and Information Systems
• /
• v.17 no.4
• /
• pp.255-277
• /
• 2011

Product Service System(PSS), which is an integrated combination of product and service, provides new value to customer and makes companies sustainable as well. The objective of this paper draws Critical Successful Factors(CSF) of PSS through multiple case study. First, we review various concepts and types in PSS and Platform business literature currently available on this topic. Second, after investigating various cases with the characteristics of PSS and platform business, we select four cases of 'iPod of Apple', 'Kindle of Amazon', 'Zune of Microsoft', and 'e-book reader of Sony'. Then, the four cases are categorized as successful and failed cases according to criteria of case selection and PSS classification. We consider two methodologies for the case selection, i.e., 'Strategies for the Selection of Samples and Cases' proposed by Bent(2006) and the seven case selection procedures proposed by Jason and John(2008). For case selection, 'Stratified sample and Paradigmatic cases' is adopted as one of several options for sampling. Then, we use the seven case selection procedures such as 'typical', 'diverse', 'extreme', 'deviant', 'influential', 'most-similar', and 'mostdifferent' and among them only three procedures of 'diverse', 'most?similar', and 'most-different' are applied for the case selection. For PSS classification, the eight PSS types, suggested by Tukker(2004), of 'product related', 'advice and consulancy', 'product lease', 'product renting/sharing', 'product pooling', 'activity management', 'pay per service unit', 'functional result' are utilized. We categorize the four selected cases as a product oriented group because the cases not only sell a product, but also offer service needed during the use phase of the product. Then, we analyze the four cases by using cross-case pattern that Eisenhardt(1991) suggested. Eisenhardt(1991) argued that three processes are required for avoiding reaching premature or even false conclusion. The fist step includes selecting categories of dimensions and finding within-group similarities coupled with intergroup difference. In the second process, pairs of cases are selected and listed. The second step forces researchers to find the subtle similarities and differences between cases. The third process is to divide the data by data source. The result of cross-case pattern indicates that the similarities of iPod and Kindle as successful cases are convenient user interface, successful plarform strategy, and rich contents. The differences between the successful cases are that, wheares iPod has been recognized as the culture code, Kindle has implemented a low price as its main strategy. Meanwhile, the similarities of Zune and PRS series as failed cases are lack of sufficient applications and contents. The differences between the failed cases are that, wheares Zune adopted an undifferentiated strategy, PRS series conducted high-price strategy. From the analysis of the cases, we generate three hypotheses. The first hypothesis assumes that a successful PSS system requires convenient user interface. The second hypothesis assumes that a successful PSS system requires a reciprocal(win/win) business model. The third hypothesis assumes that a successful PSS system requires sufficient quantities of applications and contents. To verify the hypotheses, we uses the cross-matching (or pattern matching) methodology. The methodology matches three key words (user interface, reciprocal business model, contents) of the hypotheses to the previous papers related to PSS, digital contents, and Information System (IS). Finally, this paper suggests the three implications from analyzed results. A successful PSS system needs to provide differentiated value for customers such as convenient user interface, e.g., the simple design of iTunes (iPod) and the provision of connection to Kindle Store without any charge. A successful PSS system also requires a mutually benefitable business model as Apple and Amazon implement a policy that provides a reasonable proft sharing for third party. A successful PSS system requires sufficient quantities of applications and contents.

• Research in Community and Public Health Nursing
• /
• v.12 no.2
• /
• pp.397-405
• /
• 2001

The vision disturbances of school- age children has been recognized as and important school health problem. As the visual disturbances of the school-age children is recognized as the nation's health problem. the importance of the development of educational program for visual health should be emphasized. Recently, eyeball movement and other visual health management method has been introduced for prevention or recovery of decrease in visual acuity. But, the effect of eyeball movement was not confirmed yet. And, the controversy around the treatment effect is continued. The decrease of visual acuity is one of the important school health problem as well as it causes discomfort in daily life of the students. So, it should be considered as an important subject for school health and there is a need to develop an effective intervention program for visual health. The purpose of this study is to develop and evaluate the program with the recognition of the need of the intervention for visual health. The visual health promotion program was developed by the researcher and the program was initiated by the school. Nonequivalent control group pretest-posttest design was applied for study which examined the effect of the visual health promotion program. The subjects were 742 children (experimental group: 398; control group: 344). The experiment was composed of health education and eyeball movement. Health education was provided 5 times to the children in the class room. Children of experimental group exercised eyeball movement in the class, watching video for 10 minutes two times a day. The exercise was continued for 10 weeks. The result of the study were as follows. 1) change of visual acuity Before the intervention, mean of the visual acuity was .86 for the experimental group and .91 for control group. After the intervention, mean of visual acuity was .95 for the experimental group and. 90 for the control group. There was no significant difference in the change of visual acuity between experimental and control group. 2) change of refraction. In the experimental group, 327 eyes (41.08%) were normal vision and 469 eyes (58.98%) were eyes of refraction errors, 38.82 % of the total eyes were myopia. There was no significant change in the refraction in the children with myopia after the intervention. 3) Awareness of visual acuity, change of knowledge, behavior. and attitude (1) After the intervention, there was a significant difference in the awareness of visual acuity (experimental group: 70.10%. control group: 50.97%, p<.01). (2) After the intervention, there was a significant knowledge increase in the experimental group (pp<.01). (3) There was no significant difference in the visual health behavior after the intervention. (4) There was a significant positive change in the attitude related to visual health in the experimental group ( pp<.05). 4) There was a significant positive change in the subjective discomfort of the students. But, there was no significant change in the objective eye symptom after the intervention. Even though there was no effect in the visual acuity and the change of the refraction. subjective visual health as well as the attitude and knowledge' of the children and parents toward visual health was improved significantly. Also, there was an increase in the intention of change and the awareness for the visual health management. It is suggested that various educational strategies for visual health promotion should be developed and examined for the visual health promotion of the students.

• Asia pacific journal of information systems
• /
• v.24 no.1
• /
• pp.31-50
• /
• 2014

The ubiquitous accessibility of information through mobile devices has led to an increased mobility of workers from their fixed workplaces. Market researchers estimate that by 2016, 350 million workers will be using their smartphones for business purposes, and the use of smartphones will offer new business benefits. Enterprises are now adopting mobile technologies for numerous applications to increase their operational efficiency, improve their responsiveness and competitiveness, and cultivate their innovativeness. For these reasons, various organizational aspects concerning "mobile work" have received a great deal of recent attention. Moreover, many CIOs plan to allocate a considerable amount of their budgets mobile work environments. In particular, with the consumerization of information technology, enterprise mobile applications (EMA) have played a significant role in the explosive growth of mobile computing in the workplace, and even in improving sales for firms in this field. EMA can be defined as mobile technologies and role-based applications, as companies design them for specific roles and functions in organizations. Technically, EMA can be defined as business enterprise systems, including critical business functions that enable users to access enterprise systems via wireless mobile devices, such as smartphones or tablets. Specifically, EMA enables employees to have greater access to real-time information, and provides them with simple features and functionalities that are easy for them to complete specific tasks. While the impact of EMA on organizational workers' productivity has been given considerable attention in various literatures, relatively little research effort has been made to examine how EMA actually lead to users' job performance. In particular, we have a limited understanding of what the key antecedents are of such an EMA usage outcome. In this paper, we focus on employees' perceived job performance as the outcome of EMA use, which indicates the successful role of EMA with regard to employees' tasks. Thus, to develop a deeper understanding of the relationship among EMA, its environment, and employees' perceived job performance, we develop a comprehensive model that considers the perceived-fit between EMA and employees' tasks, satisfaction on EMA, and the organizational environment. With this model, we try to examine EMA to explain how job performance through EMA is revealed from both the task-technology fit for EMA and satisfaction on EMA, while also considering the antecedent factors for these constructs. The objectives of this study are to address the following research questions: (1) How can employees successfully manage EMA in order to enhance their perceived job performance? (2) What internal and/or external factors are important antecedents in increasing EMA users' satisfaction on MES and task-technology fit for EMA? (3) What are the impacts of organizational (e.g. organizational agility), and task-related antecedents (e.g., task mobility) on task-technology fit for EMA? (4) What are the impacts of internal (e.g., self-efficacy) and external antecedents (e.g., system reputation) for the habitual use of EMA? Based on a survey from 254 actual employees who use EMA in their workplace across industries, our results indicate that task-technology fit for EMA and satisfaction on EMA are positively associated with job performance. We also identify task mobility, organizational agility, and system accessibility that are found to be positively associated with task-technology fit for EMA. Further, we find that external factor, such as the reputation of EMA, and internal factor, such as self-efficacy for EMA that are found to be positively associated with the satisfaction of EMA. The present findings enable researchers and practitioners to understand the role of EMA, which facilitates organizational workers' efficient work processes, as well as the importance of task-technology fit for EMA. Our model provides a new set of antecedents and consequence variables for a TAM involving mobile applications. The research model also provides empirical evidence that EMA are important mobile services that positively influence individuals' performance. Our findings suggest that perceived organizational agility and task mobility do have a significant influence on task-technology fit for EMA usage through positive beliefs about EMA, that self-efficacy and system reputation can also influence individuals' satisfaction on EMA, and that these factors are important contingent factors for the impact of system satisfaction and perceived job performance. Our findings can help managers gauge the impact of EMA in terms of its contribution to job performance. Our results provide an explanation as to why many firms have recently adopted EMA for efficient business processes and productivity support. Our findings additionally suggest that the cognitive fit between task and technology can be an important requirement for the productivity support of EMA. Further, our study findings can help managers in formulating their strategies and building organizational culture that can affect employees perceived job performance. Managers, thus, can tailor their dependence on EMA as high or low, depending on their task's characteristics, to maximize the job performance in the workplace. Overall, this study strengthens our knowledge regarding the impact of mobile applications in organizational contexts, technology acceptance and the role of task characteristics. To conclude, we hope that our research inspires future studies exploring digital productivity in the workplace and/or taking the role of EMA into account for employee job performance.

• Journal of Science Education
• /
• v.32 no.2
• /
• pp.1-16
• /
• 2008

The purpose of this study was to analyze about STS contents in the next generation science textbook for 10th grade according to curriculum revision 2007 and high school science textbooks focused on the Earth Science which were published according to the 7th curriculum. The contents of STS were analyzed by the STS topics of Yager(1989), Piel's standard(1981), and student activities by SATIS. The results of this study are the same as follows: 'The next generation science textbook' was shown that 20.9% is STS material amount in average by Yager's standard. 'High school science textbooks' were shown that 11.3% is STS material amount in average. Based on the STS topics by Yager's standard, most of STS content is focused on 'Relativity with local community', 'Application of science' and 'Cooperative work on real problems'. However, there is rare contents such as 'Multiple dimensions of science', 'Practice with decision-making strategies' and 'Evaluation concerned for getting and using information' in the next generation science textbook. In high school science textbooks were shown that 'Applicability of science' is the highest and 'Relativity with local community' is the next high contents. Based on the STS topics by Piel's standard, most of STS contents are focused on 'Environmental quality', 'Space research' and 'National defence' in the next generation science textbook. But high school science textbooks are focused on 'Natural resources' and 'Technology development'. The activities were analyzed by SATIS student activities. The major categories of activities included in the next generation science textbook were 'Investigation', 'Simulation' and 'Data analysis'. But, there were rare activities like 'Roleplaying', 'Research design' and 'Simulation' in high school science textbooks.

• Journal of Acupuncture Research
• /
• v.19 no.2
• /
• pp.51-64
• /
• 2002

We have compared(using the same series of experimental tissue samples) the levels of proteolytic enzyme activities and free radical-induced protein damage in synovial fluid from RA and CPH cases. Many protease types showed significantly increased (typically by a factor of approximately 2-3-fold) activity in RA, compared to normal rats. However, CPH significantly reduced the cytoplasmic enzyme activities of arginyl aminopeptidase, leucyl aminopeptidase, pyroglutamyl aminopeptidase, tripeptidyl aminopeptidase, and proline endopeptidase to almost about 1/10 each. For the Iysosomal proteases, synovial fluid samples from RA rats, CPH significantly reduced the enzyme activities of cathepsin B, dipeptidyl aminopeptidase I and dipeptidyl aminopeptidase II. In extracellular matrix degrading(collagenase, tissue elastase) and leukocyte as sociated proteases (leukocyte elastase, cathepsin G), CPH decreased these enzyme activities of collagenase, tissue elastase and leukocyte associated elastase in RA. In cytoplasmic and lysosomal protease activities in plasma from RA. CPH and normal plasma samples were not significantly different, suggesting that altered activity of plasma proteases (particularly those enzymes putatively involved in the immune response) is not a contributory factor in the pathogenesis of RA. In addition, the level of free radical induced damage to synovial fluid proteins was approximately twice that in RA, compared with CPH. CPH significantly decreased the level of ROS induced oxidative damage to synovial fluid proteins (quantified as protein carbonyl derivative). Therefore we conclude that both proteolytic enzymes and free radicals are likely to be of equal potential importance as damaging agents in the pathogenesis of inflammatory joint disease, and that the design of novel therapeutic strategies for patients with the latter disorder should include both protease inhibitory and free radical scavenging elements. In addition, the protease inhibitory element should be designed to inhibit the action of a broad range of protease mechanistic types (i.e. cysteine-, metallo- and serine- proteinases and peptidases). However, increased protein damage induced by ROS could not be rationalised in terms of compromised antioxidant total capacity, since the latter was not significantly altered in RA synovial fluid or plasma compared with CPH.