• Restorative Dentistry and Endodontics
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• v.39 no.1
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• pp.12-16
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• 2014

Objectives: Extensively destroyed teeth are commonly restored with composite resin before cavity preparation for indirect restorations. The longevity of the restoration can be related to the proper bonding of the resin cement to the composite. This study aimed to evaluate the microshear bond strength of two self-adhesive resin cements to composite resin. Material and Methods: Composite discs were subject to one of six different surface pretreatments: none (control), 35% phosphoric acid etching for 30 seconds (PA), application of silane (silane), PA + silane, PA + adhesive, or PA + silane + adhesive (n = 6). A silicone mold containing a cylindrical orifice ($1mm^2$ diameter) was placed over the composite resin. RelyX Unicem (3M ESPE) or BisCem (Bisco Inc.) self-adhesive resin cement was inserted into the orifices and light-cured. Self-adhesive cement cylinders were submitted to shear loading. Data were analyzed by two-way ANOVA and Tukey's test (p < 0.05). Results: Independent of the cement used, the PA + Silane + Adhesive group showed higher microshear bond strength than those of the PA and PA + Silane groups. There was no difference among the other treatments. Unicem presented higher bond strength than BisCem for all experimental conditions. Conclusions: Pretreatments of the composite resin surface might have an effect on the bond strength of self-adhesive resin cements to this substrate.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.4
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• pp.423-429
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• 2002

Time-out is one of the basic but important functions in real-time programming. However, the C language used commonly in the embedded real-time systems doesn't support this capability. For this capability, there have been numerous studies on language extension and/or special purpose real-time kernel (or engine). Those require preprocessor or new kernel support. In this paper, we propose a time-out facility supported by a library and some macro functions with a minimum dependency on operating systems. Furthermore, we also provide a structured _within statement, a macro function which makes programming easy. We have implemented this for the LINUX and the DOS environment, and for the POSIX multithread environment as well.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.7
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• pp.691-696
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• 2004

The electronic state and chemical bonding of $\beta$-MnO$_2$ with transition metal dopants were theoretically investigated by DV-X$_{\alpha}$ (the discrete variational X$_{\alpha}$) method, which is a sort of the first principles molecular orbital method using the Hartree-Fock-Slater approximation. The calculations were performed with a $_Mn_{14}$ MO$_{56}$ )$^{-52}$ (M = transition metals) cluster model. The electron energy level, the density of states (DOS), the overlap population, the charge density distribution, and the net charges, were calculated. The energy level diagram of MnO$_2$ shows the different band structure and electron occupancy between the up spin states and down spin states. The dopant levels decrease between the conduction band and the valence band with the increase of the atomic number of dopants. The covalency of chemical bonding was shown to increase and ionicity decreased in increasing the atomic number of dopants. Calculated results were discussed on the basis of the interaction between transition metal 3d and oxygen 2p orbital. In conclusion it is expected that when the transition metals are added to MnO$_2$ the band gap decreases and the electronic conductivity increases with the increase of the atomic number of dopants. the atomic number of dopants.

• The Korean Journal of Pain
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• v.33 no.3
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• pp.245-257
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• 2020

Background: Musculoskeletal pain is associated with obesity; however, information on factors associated with pain in adults with obesity and severe obesity is limited. The purpose of this study was to assess the prevalence of musculoskeletal pain by site and intensity of pain and associated factors in individuals with severe obesity (body mass index ≥ 35.0 kg/㎡). Methods: Baseline data from the DieTBra Trial study evaluating pain symptoms in nine body regions over the last seven days using the Nordic Questionnaire on Musculoskeletal Symptoms and Numerical Pain Scale. The variables analyzed using multiple Poisson regression with hierarchical analysis were: sociodemographic, lifestyle, food consumption, clinical, and anthropometric, and the outcome was moderate and intense pain. Results: In 150 participants, there was a high prevalence of ankle and foot pain (68.7%), lower back pain (62.7%), pain in the knees (53.3%) and upper back pain (52.0%), with a predominance of intense pain. Factors associated with pain according to specific sites were: type 2 diabetes with hand/wrist pain; sedentary time with hip pain; insomnia with pain in the hip and knee; edema in the lower limbs with pain in the lower back and ankles/feet; degree of obesity with ankle/foot pain; and percentage of total fat with ankle/foot pain. Conclusions: There was a high prevalence of pain and intense pain in individuals with severe obesity and an association with clinical variables, the degree of obesity, and sedentary lifestyle.

• Safety and Health at Work
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• v.8 no.4
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• pp.347-355
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• 2017

Background: The objective of this article is to make some analysis on the process of work and accidents occurring in slaughterhouses, evidenced in the Brazilian documentary film called Flesh and Bone. As such, it was necessary to discuss an alternative theoretical concept in relation to theories about health and safety at work. This alternative discussion focuses on the concepts of biopower and biopolitics. Methods: The use of audiovisual elements in research is not new, and there is already a branch of studies with methodological and epistemological variations. The Brazilian documentary Flesh and Bone was the basis for the research. The analysis of this documentary will be carried out from two complementary perspectives: "textual analysis" and "discourse analysis." Results: Flesh and Bone presents problems related to health and safety at work in slaughterhouses because of the constant exposure of workers to knives, saws, and other sharp instruments in the workplace. The results show that in favor of higher production levels, increased overseas market sales, and stricter quality controls, some manufacturers resort to various practices that often result in serious injuries, disposal, and health damages to workers. Conclusion: Flesh and Bone, by itself, makes this explicit in the form of denunciation based on the situation of these workers. What it does not make clear is that, in the context of biopolitics, the actions aimed at solving these problems or even reducing the negative impacts for this group of workers, are not efficient enough to change such practices.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.397-408
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• 1999

In the year of 1998 the heads of dog raised in Korea were 1,846,411 and the number of the households raising dogs is 819,112 which means that the heads of pet dog and edible dos were 819,112 and 1,027,299, respectively, because each house raised about one pet dog and one edible dog breeder raised hundreds of dog. in 1998 the number of exported dogs came to 28 heads and that of imported dogs was 296 heads. But edible dog that was slaughtered or processed has not been reported to be exported or imported. It is known that at the Shenyang Xingshan Food Ltd in Shenyang, Chinese, 300,000 heads of dogs were rais-ed slaughtered and processed of dog meat per year, and 20% of them were exported. In Korea the cook of dog meat is a special food culture with a long history. During the Chosun dynasty dog meat had been eaten to be cooked diversely such as Gaejangkuk(a soup) Suyuk(a boiled meat) Sundae(a sausage) Kui(a roasted meat) Gaezim(a steamed meat) Nurumi(a meat roasted or fried to which lot of spice paste are added) Gaesoju(an extract) Musulju(a wine) Musuldang(a sweet cane) Now it is cooked as Bosintang(a soup) Suyuk (a boiled meat) Jeongol (boiled meat mixed with spices vegetables and water on the pot) Duruchigi(boiled meat added spice vegatasble and slightly roasted) Muchim(boiled meat added by spice and mixed) Gaesoju(an extract) with the number of recipes lessened compared with those of the old times. The reason is due to the intervention and criticism from foreign countries. But foreigner's blame for the dog meat is absurd and excessive action because Korea raises exceptional dogs which are edible.

• Journal of Korea Multimedia Society
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• v.12 no.8
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• pp.1099-1108
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• 2009

The study of IP address allocation in MANET can be categories into Stateful and Stateless. The one, special node monitors other nodes' IP address and allocates IF address. And the other, node generates IP address by itself. Nodes in MANET have mobility and restricted resource, so Stateless is more suitable than Stateful. But, in Stateless, node requires DAD process because of unique IP address allocation. And Dos attack can be happened in DAD precess. In this paper, we propose a security method on preventing DoS attack against DAD in MANET using one-way hash function. Since, Computation of one-way hash function is suitable for nodes' restricted resource character in MANET. And we evaluate performance using NS2 and compare with other security method which is CGA using signature.

• Geomechanics and Engineering
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• v.21 no.3
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• pp.247-258
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• 2020

The shear strength of unsaturated soils, a research hotspot in geotechnical engineering, has great guiding significance for geotechnical engineering design. Although kinds of calculation models for the shear strength of unsaturated soil have been put forward by predecessors, there is still need for new models to extensively consider the nonlinear variation of shear strength, particularly for the nonlinear effect of the net normal stress on the shear strength of unsaturated soil. Here, the shear strength of unsaturated soils is explored to study the nonlinear effects of net normal stress with the introduction of a general nonlinear Mohr-Coulomb (M-C) strength criterion, and the relationship between the matric suction (or suction stress) and degree of saturation (DOS) constructed by the soil-water characteristics curve (SWCC) of van Genuchten is also applied for unsaturated soil. Then, two calculation models (i.e., an envelope shell model and an effective stress model) are established for the shear strength of unsaturated soils under the nonlinear strength theory. In these two models, the curve of the shear strength of unsaturated soils versus the net normal stress exhibits a tendency to gently. Moreover, the proposed formulas have flexibility and convenience with five parameters (for the effective stress model) or six parameters (for the envelope shell model), which are from the M-C strength parameters of the saturated soil and fitting parameters of SWCC of van Genuchten. Thereafter, by comparison with the classical theory of the shear strength of unsaturated soils from some actual cases, the rationality and accuracy of the present models were verified.

• Korean Journal of Remote Sensing
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• v.6 no.2
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• pp.89-113
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• 1990

The purpose of this study is to develop means to apply GIS and remote sensing technology to the analysis of Korean urban open spaces. To achieve this objective, a framework of analysis of urban open spaces was developed, and then the framework was applied for the evaluation of the potential and suitability of open spaces of Ansan City, which is a new town developed to accomodate industries relocation from Seoul, Korea, mainly due to their pollution problems. The software used in this study are IDRISI, a grid-based GIS, and KMIPS, a remote sensing analysis system. Both packages are based on IBM PC/AT computers with Microsoft DOS. Landsat MSS and TM data were used for the land use classification, land use change detection, and analysis of transformed vegetation indices. The size of the geographic data base is 110 rows and 150 columns with the spatial resolution of 100m$\times$100m. The framework of analysis includes both quanititative and qualitative analysis of open spaces. The quantitative analysis includes size and distribution of open spaces, urban develpment of open spaces, and the degree of vegree of vegetation removal of the study area. The qualitative analysis includes evaluative criteria for primary productivity of land, park use potential, major visual resources, and urban environmental control. The findings of this study can be summarized as follows. First, the size of builtup areas increased 18.73km$^2$, while the size of forest land decreased 10.86km$^2$ during last ten years. Agricultural lands maintained its size, but shifted toward outside of the city into forest. Second, the potential of open spaces for park use is limited mainly due to their lack of accessibility and connectivity among open spaces, in spite of ample acreage and good site conditions. Third, major landscape elements and historic sites should be connected to the open space system of the city by new accesses and buffers.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.4
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• pp.743-754
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• 2019

The erosive potential of precipitation can be evaluated by the kinetic energy transferred to the soil by the impact of the rain drop. A kinetic energy rate of the rain drops was estimated by the disdrometer classifying impact signals. This equation in the form of power presented an adjustment measure between the rain rate and rainfall quantity of 97% and 95% for continental and maritime rains, respectively. The exponent of the power equation, initially, shows no dependence on the type of rainfall. However, the multiplicative factor presented variation, which can be adjusted according to rainfall events. This equation was validated by the coefficient of determination, the average absolute error and the confidence error. The kinetic energy of precipitation, associated to certain types of soil, will allow the determination of the potential of the erosion caused by the rains.