• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.12
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• pp.605-619
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• 2014

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2013. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of fluid machinery, pipes and relative parts including orifices, dampers and ducts, fuel cells and power plants, cooling and air-conditioning, heat and mass transfer, two phase flow, and the flow around buildings and structures. Research issues dealing with home appliances, flows around buildings, nuclear power plant, and manufacturing processes are newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for general analytical model for desiccant wheels, the effects of water absorption on the thermal conductivity of insulation materials, thermal properties of Octadecane/xGnP shape-stabilized phase change materials and $CO_2$ and $CO_2$-Hydrate mixture, effect of ground source heat pump system, the heat flux meter location for the performance test of a refrigerator vacuum insulation panel, a parallel flow evaporator for a heat pump dryer, the condensation risk assessment of vacuum multi-layer glass and triple glass, optimization of a forced convection type PCM refrigeration module, surface temperature sensor using fluorescent nanoporous thin film. In the area of pool boiling and condensing heat transfer, researches on ammonia inside horizontal smooth small tube, R1234yf on various enhanced surfaces, HFC32/HFC152a on a plain surface, spray cooling up to critical heat flux on a low-fin enhanced surface were actively carried out. In the area of industrial heat exchangers, researches on a fin tube type adsorber, the mass-transfer kinetics of a fin-tube-type adsorption bed, fin-and-tube heat exchangers having sine wave fins and oval tubes, louvered fin heat exchanger were performed. (3) In the field of refrigeration, studies are categorized into three groups namely refrigeration cycle, refrigerant and modeling and control. In the category of refrigeration cycle, studies were focused on the enhancement or optimization of experimental or commercial systems including a R410a VRF(Various Refrigerant Flow) heat pump, a R134a 2-stage screw heat pump and a R134a double-heat source automotive air-conditioner system. In the category of refrigerant, studies were carried out for the application of alternative refrigerants or refrigeration technologies including $CO_2$ water heaters, a R1234yf automotive air-conditioner, a R436b water cooler and a thermoelectric refrigerator. In the category of modeling and control, theoretical and experimental studies were carried out to predict the performance of various thermal and control systems including the long-term energy analysis of a geo-thermal heat pump system coupled to cast-in-place energy piles, the dynamic simulation of a water heater-coupled hybrid heat pump and the numerical simulation of an integral optimum regulating controller for a system heat pump. (4) In building mechanical system research fields, twenty one studies were conducted to achieve effective design of the mechanical systems, and also to maximize the energy efficiency of buildings. The topics of the studies included heating and cooling, HVAC system, ventilation, and renewable energies in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment is mostly focused on indoor environment and building energy. The main researches of indoor environment are related to infiltration, ventilation, leak flow and airtightness performance in residential building. The subjects of building energy are worked on energy saving, operation method and optimum operation of building energy systems. The remained studies are related to the special facility such as cleanroom, internet data center and biosafety laboratory. water supply and drain system, defining standard input variables of BIM (Building Information Modeling) for facility management system, estimating capability and providing operation guidelines of subway station as shelter for refuge and evaluation of pollutant emissions from furniture-like products.

• Management & Information Systems Review
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• v.35 no.1
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• pp.51-68
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• 2016

In this paper, we aim to analyze the effect of accounting policy change subsequent to the adoption of K-IFRS in Korea, whereby the firms are required to recognize impairment losses on goodwill on a periodic basis rather than to amortize over a specific period. As a principle-based accounting standard, the K-IFRS expands the scope of fair value measurement with a view to enhance the relevance and timeliness of accounting information. In the same vein, intangibles with indefinite useful life, of which goodwill is an example, are subject to regulatory impairment tests at least once a year. Related literature on the impact of mandatory change in goodwill policy document that impairment recognition is more likely to be practiced opportunistically, mainly because managers have a greater discretion to conduct the tests under K-IFRS. However, existing literature examined the frequency and/or magnitude of the goodwill impairment before versus after the K-IFRS adoption, failing to notice the impairment symptoms at individual firm level. Borrowing the definition of impairment symptoms suggested by Ramanna and Watts(2012), this study performs a series of tests to determine whether the goodwill impairment recognition achieves the goal of communicating timelier information under the K-IFRS regime. Using 947 firm-year observations from domestic companies listed in KRX and KOSDAQ markets from 2008 to 2011, we document overall delays in recognizing impairment losses on goodwill after the adoption of K-IFRS relative to prior period, based on logistic and OLS regression analyses. The results are qualitatively similar in robustness tests, which use alternative proxy for goodwill impairment symptom. Afore-mentioned results indicate that managers are likely to take advantage of the increased discretion to recognize the impairment losses on goodwill rather than to provide timelier information on impairment, inconsistent with the goal of regulatory authority, which is in line with the improvement of timeliness and relevance of accounting information in conjunction with the full implementation of K-IFRS. This study contributes to the extant literature on goodwill impairment from a methodological viewpoint. We believe that the method employed in this paper potentially diminishes the bias inherent in researches relying on ex post impairment recognition, by conducting tests based on ex ante impairment symptoms, which allows direct examination of the timeliness changes between before and after K-IFRS adoption.

• Journal of Environmental Policy
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• v.4 no.1
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• pp.93-111
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• 2005

Defining soil quality in scopes and applications is one of the prerequisite for the sustainable management of soil environment to orient researches, strategies and policies. However, definition of soil quality is controversial depending upon a viewpoint of soil science or soil environment. Soil quality can be, irrespective of the disciplines, defined as the capacity of a soil to function within ecosystem boundaries to sustain biological productivity, maintain environmental quality and promote plant and animal health. Common to all of the soil quality concepts can be summarized as the capacity of soil to function effectively at present and in the future. The OECD includes soil quality as one of the agri-environment indicators. This article intends to i) summarize the current soil quality research, and ii) provide information on protocol of soil quality assessment. A framework for soil quality was divided into three steps: indicator selection as minimum data set (MDS), scoring of the selected indicators, and integration of scores into soil quality index. Korean government suggested possible physical and chemical indicators such as bulk density and organic matter for paddy and upland soils to OECD. The framework of soil quality assessment is not yet implemented in Korea. Countries such as USA, Canada and New Zealand have constructed the framework on soil quality assessment and developed a user-friendly version of soil quality assessment tools to evaluate the integrated effects of various soil management practices. The protocol provided in this review might help policymakers, scientists, and administrators improve awareness about soil quality and understand the way of soil environment management.

• Journal of Gastric Cancer
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• v.8 no.4
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• pp.225-231
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• 2008

Purpose: Laparoscopic gastric resection (LGR) is increasingly being used instead of open gastric resection (OGR) as the standard surgical treatment for gastric submucosal tumors. Yet there are few reports on which technique shows better postoperative outcomes. This study was performed to compare these two treatment modalities for gastric submucosal tumors by evaluating the postoperative outcomes. We also provide an analysis of the learning curve for LGR. Materials and Methods: Between 2003.4 and 2008.8, 103 patients with a gastric submucosal tumor underwent either LGR (N=78) or OGR (n=25). A retrospective review was performed on a prospectively obtained database of 103 patients. We reviewed the data with regard to the operative time, the blood loss during the operation, the time to the first soft diet, the postoperative hospital stay, the tumor size and the tumor location. Results: The clinicopatholgic and tumor characteristics of the patients were similar for both groups. There was no open conversion in the LGR group. The mean operation time and the bleeding loss were not different between the LGR group and the OWR group. The time to first soft diet (3.27 vs. 6.16 days, P<0.001) and the length of the postoperative hospital stay (7.37 vs. 8.88 days, P=0.002) were shorter in the LGR group compared to the OGR group. The tumor size was bigger in the OGR group than that in the LGR group (6.44 vs. 3.65 cm, P<0.001). When performing laparoscopic gastric resection of gastric SMT, the surgeon was able to decrease the operation time and bleeding loss with gaining more experience. We separated the total cases into 3 periods to compare the operation time, the bleeding losses and the complications. The third period showed the shortest operation time, the least bleeding loss and the fewest complications. Conclusion: LGR for treating a gastric submucosal tumor was superior to OGR in terms of the postoperative outcomes. An operator needs some experience to perform a complete laparoscopic gastric resection. Laparoscopic resection could be considered the first-line treatment for gastric submucosal tumors.

• Journal of Intelligence and Information Systems
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• v.21 no.1
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• pp.119-142
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• 2015

With the explosive growth in the volume of information, Internet users are experiencing considerable difficulties in obtaining necessary information online. Against this backdrop, ever-greater importance is being placed on a recommender system that provides information catered to user preferences and tastes in an attempt to address issues associated with information overload. To this end, a number of techniques have been proposed, including content-based filtering (CBF), demographic filtering (DF) and collaborative filtering (CF). Among them, CBF and DF require external information and thus cannot be applied to a variety of domains. CF, on the other hand, is widely used since it is relatively free from the domain constraint. The CF technique is broadly classified into memory-based CF, model-based CF and hybrid CF. Model-based CF addresses the drawbacks of CF by considering the Bayesian model, clustering model or dependency network model. This filtering technique not only improves the sparsity and scalability issues but also boosts predictive performance. However, it involves expensive model-building and results in a tradeoff between performance and scalability. Such tradeoff is attributed to reduced coverage, which is a type of sparsity issues. In addition, expensive model-building may lead to performance instability since changes in the domain environment cannot be immediately incorporated into the model due to high costs involved. Cumulative changes in the domain environment that have failed to be reflected eventually undermine system performance. This study incorporates the Markov model of transition probabilities and the concept of fuzzy clustering with CBCF to propose predictive clustering-based CF (PCCF) that solves the issues of reduced coverage and of unstable performance. The method improves performance instability by tracking the changes in user preferences and bridging the gap between the static model and dynamic users. Furthermore, the issue of reduced coverage also improves by expanding the coverage based on transition probabilities and clustering probabilities. The proposed method consists of four processes. First, user preferences are normalized in preference clustering. Second, changes in user preferences are detected from review score entries during preference transition detection. Third, user propensities are normalized using patterns of changes (propensities) in user preferences in propensity clustering. Lastly, the preference prediction model is developed to predict user preferences for items during preference prediction. The proposed method has been validated by testing the robustness of performance instability and scalability-performance tradeoff. The initial test compared and analyzed the performance of individual recommender systems each enabled by IBCF, CBCF, ICFEC and PCCF under an environment where data sparsity had been minimized. The following test adjusted the optimal number of clusters in CBCF, ICFEC and PCCF for a comparative analysis of subsequent changes in the system performance. The test results revealed that the suggested method produced insignificant improvement in performance in comparison with the existing techniques. In addition, it failed to achieve significant improvement in the standard deviation that indicates the degree of data fluctuation. Notwithstanding, it resulted in marked improvement over the existing techniques in terms of range that indicates the level of performance fluctuation. The level of performance fluctuation before and after the model generation improved by 51.31% in the initial test. Then in the following test, there has been 36.05% improvement in the level of performance fluctuation driven by the changes in the number of clusters. This signifies that the proposed method, despite the slight performance improvement, clearly offers better performance stability compared to the existing techniques. Further research on this study will be directed toward enhancing the recommendation performance that failed to demonstrate significant improvement over the existing techniques. The future research will consider the introduction of a high-dimensional parameter-free clustering algorithm or deep learning-based model in order to improve performance in recommendations.

• International Journal of Highway Engineering
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• v.11 no.4
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• pp.69-78
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• 2009

Korea has achieved significant economic growth with building the Gyeongbu Expressway. As the number of new road construction projects has decreased, it becomes more important to maintain optimal status of the current road networks. One of the best ways to accomplish it is weight enforcement as active control measure of traffic load. This study is to develop High-speed Weigh-in-motion System in order to enhance efficiency of weight enforcement, and to analyze patterns of overloaded trucks on highways through the system. Furthermore, it is to review possibilities of developing overweight control system with application of the HS-WIM system. The HS-WIM system developed by this study consists of two sets of an axle load sensor, a loop sensor and a wandering sensor on each lane. A wandering sensor detects whether a travelling vehicle is off the lane or not with the function of checking the location of tire imprint. The sensor of the WIM system has better function of classifying types of vehicles than other existing systems by detecting wheel distance and tire type such as single or dual tire. As a result, its measurement errors regarding 12 types of vehicle classification are very low, which is an advantage of the sensor. The verification tests of the system under all conditions showed that the mean measurement errors of axle weight and gross axle weight were within 15 percent and 7 percent respectively. According to the WIM rate standard of the COST-323, the WIM system of this study is ranked at B(10). It means the system is appropriate for the purpose of design, maintenance and valuation of road infrastructure. The WIM system in testing a 5-axle cargo truck, the most frequently overloaded vehicle among 12 types of vehicles, is ranked at A(5) which means the system is available to control overloaded vehicles. In this case, the measurement errors of axle load and gross axle load were within 8 percent and 5 percent respectively. Weight analysis of all types of vehicles on highways showed that the most frequently overloaded vehicles were type 5, 6, 7 and 12 among 12 vehicle types. As a result, it is necessary to use more effective overweight enforcement system for vehicles which are seriously overloaded due to their lift axles. Traffic volume data depending upon vehicle types is basic information for road design and construction, maintenance, analysis of traffic flow, road policies as well as research.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.13 no.2
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• pp.111-119
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• 2013

Purpose: Mucopolysaccharidosis type I (MPS I) is a lysosomal storage disorder caused by deficiency of the enzyme ${\alpha}$-L-iduronidase, which leads to a broad spectrum of multisystemic manifestations. Short stature and decreased growth velocity are prominent features of MPS I. The aim of the present study was to evaluate the effect of enzyme replacement therapy (ERT) on growth of Korean MPS I patients from a single center. Methods: Height data were obtained by retrospective chart review of 10 Korean patients with MPS I who had received ERT for a minimum of 3 years. Height was expressed as standard deviation scores (SDS) based on normative data. Annual growth rates were calculated before and during ERT. A piecewise regression model was used to analyze height z-scores before and after treatment. Individual analysis was performed for impact of phenotype [(severe (Hurler) versus attenuated (Hurler-Scheie, Scheie)] on growth. Results: Annual growth was 3.3 cm (z-score= -0.21) in the year before ERT and 6.2 cm (z-score= 0.17), 5.8 cm (z-score= 0.07), and 3.8 cm (z-score= -0.4) in the first, second, and third years of ERT, respectively. Regression analysis showed improvement in the slope after ERT (difference= 0.04; P=0.022). Estimated slope differences between severe and attenuated phenotypes were statistically significant before (P=0.001) and after treatment (P<0.0001), although no significant difference was noted when stratified by phenotype. Conclusion: ERT with aldurazyme appears to have a positive impact on linear growth in patients with MPS I.

• Journal of Hospice and Palliative Care
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• v.4 no.1
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• pp.26-40
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• 2001

Purpose : The purpose of this study was to develop task guidelines for hospice team members. The task range of all personnel who work for hospice institutions was identified, and a tool describing roles and tasks of the hospice team members was developed based on review of related literature, both domestic and international. Methods : The content validity of the tool was assured by an expert panel through two phases of discussion. The first phase of the study included a survey conducted from December 1999 to January 2000 for a total of 126 hospice experts and practitioners affiliated with domestic hospice institutions. The second phase of the study included 35 subjects. The data were collected using a survey when the investigators visited each hospice institution. The data were analyzed using descriptive statistics. Results : 1) In the first phase of the study, all items scored over 80 points in CVI were selected as the roles and tasks of hospice coordinator, nurse, pastor, social worker, pharmacist, nutritionist, therapist, volunteer, and nurse aide. However, two items were excluded because they scored below 80 points: an item describing eligibility of a physician, a person who has a license for managing anesthetic agents was scored as 78.6 points, and an item describing the eligibility of the team leader of volunteers, a person educated at the graduate level was scored as 74.7 points. 2) In the second phase of the study, all items scored over 80 points in CVI were selected as the roles and tasks of hospice nurse, pastor, social worker, pharmacist, nutritionist, therapist, volunteer, and nurse aide. Of the roles of the hospice coordinator, however, the item scored as 77.9 points, assess and plan a patients physical, social, emotional, and spiritual status, and, of the roles of the team leaders of volunteers, the item scored as 78.6, attend a team meeting once a week and participate in building an standard nursing plan for patients were included in the tool since they scored over 80 points in the first phase of the study. Conclusion : The developed task guideline should be further modified and revised based on the findings of a preliminary application in the actual field. There is also a need of continuous research for developing more culturally-appropriate task guidelines for hospice team members.

• Korean Journal of Heritage: History & Science
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• v.51 no.4
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• pp.120-145
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• 2018

This study intended to examine the drainage facility of Gyeongbokgung Palace based on the traces of the relic found during the excavation survey. Historical records indicate that various efforts have been made for smooth drainage facility for the palace since the foundation of the Joseon Dynasty. Although there are no drawings showing the image of early appearance of Gyeongbokgung Palace during the foundation, it is possible to estimate it through the drawings prepared after the King Yeongjo's reign. The image of the palace after reconstruction can be seen through the "Bukgwoldohyeong" and other relevant documents. At this present, since the survey intends to determine the image of Gyeongbokgung Palace during the reign of King Gojong based on the standard restoration plan of the Cultural Heritage Administration, this study also focused on the drainage facility of Gyeongbokgung Palace during King Gojong's reign, particularly on the collecting wells and culverts of six areas including "Chimjeon Hall", "Taewonjeon Hall", "Geoncheongung Hall", "Sojubang Hall", "Hamhwadang - Jipgyeongdang - Yeonghundang Hall", and "Heungbokjeon Hall". Gyeongbokgung Palace is divided into various zones composed of the central halls and surrounding corridors, and the drains also primarily start from each hall and later join the central drain of the zone. The central drain then leads to the "Eo-gu(御溝)" and the water led to the "Eo-gu" is finally discharged through the water gate. It appears that this series of processes were basically devised to coordinate artificial drain with the natural drain using the natural geographical features of the palace. Research showed that the collecting well where the draining begin was installed in the area where a large amount of household sewage was generated but mostly in the corners where corridors met or corridors and wall met. This appears to be an arrangement to handle the water falling from the roof and household sewage. Also, "Ju(廚)" was installed mainly at the end of the corridor to handle household sewage. The installation of these drainage facilities shows the possibility that the drainage of Gyeongbokgung was very compact under a series of plans.

• Journal of Hospice and Palliative Care
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• v.22 no.3
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• pp.105-116
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• 2019

Purpose: Pediatric palliative care (PPC) is emphasized as standard care for children with life-limiting conditions to improve the quality of life. In Korea, a government-funded pilot program was launched only in July 2018. Given that, this study examined various PPC delivery models in other countries to refine the PPC model in Korea. Methods: Target countries were selected based on the level of PPC provided there: the United Kingdom, the United States, Japan, and Singapore. Relevant literature, websites, and consultations from specialists were analyzed by the integrative review method. Literature search was conducted in PubMed, Google, and Google Scholar, focusing publications since 1990, and on-site visits were conducted to ensure reliability. Analysis was performed on each country's process to develop its PPC scheme, policy, funding model, target population, delivery system, and quality assurance. Results: In the United Kingdom, community-based free-standing facilities work closely with primary care and exchange advice and referrals with specialized PPC consult teams of children's hospitals. In the United States, hospital-based specialized PPC consult teams set up networks with hospice agencies and home healthcare agencies and provide PPC by designating care coordinators. In Japan, palliative care is provided through several services such as palliative care for cancer patients, home care for technology-dependent patients, other support services for children with disabilities and/or chronic conditions. In Singapore, a home-based PPC association plays a pivotal role in providing PPC by taking advantage of geographic accessibility and cooperating with tertiary hospitals. Conclusion: It is warranted to identify unmet needs and establish an appropriate PPD model to provide need-based individualized care and optimize PPC in South Korea.