• Korean Journal of Mathematics
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• v.29 no.1
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• pp.137-167
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• 2021

Spherical fuzzy set (SFS) is also one of the fundamental concepts for address more uncertainties in decision problems than the existing structures of fuzzy sets, and thus its implementation was more substantial. The well-known sine trigonometric function maintains the periodicity and symmetry of the origin in nature and thus satisfies the expectations of the experts over the multi parameters. Taking this feature and the significance of the SFSs into the consideration, the main objective of the article is to describe some reliable sine trigonometric laws (ST L) for SFSs. Associated with these laws, we develop new average and geometric aggregation operators to aggregate the Spherical fuzzy numbers (SFNs). Then, we presented a group decision- making (DM) strategy to address the multi-attribute group decision making (MAGDM) problem using the developed aggregation operators. In order to verify the value of the defined operators, a MAGDM strategy is provided along with an application for the selection of laptop. Moreover, a comparative study is also performed to present the effectiveness of the developed approach.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.2
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• pp.70-78
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• 2022

The trenchless entire repair technology (TERT) have many different names depending on the companies, and they have the same or similar methods as well as materials. In addition, there was quiet difficulty in application of field working and even confuse to classify for new TERT, while application criteria of TERT is not listed systematically. This study proposed standardization and method for TERT affecting by pipe condition, working materials, working method, specification/quantity per unit according to field condition, strange affairs and others. Determination criteria of defective sewer pipe has proposed to effective method which modify a criteria between Ministry of Environment and Seoul Metropolitan City. A Cured-in-place pipe (CIPP) is suitable for TERT, and the design criteria for the entire broken pipe are proposed when the pipe itself deforms more than 10%. A check lists are specimen preparing, hardening site made by clamped mold, numbers, flexural and tensile property, water leak and desquamation test, and have to use material property of minimum CIPP value depend on ISO 11296-4, ISO 11297-4, KS M3550-7 and KS M3550-9.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.667-671
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• 2005

Analytical hierarchy process (AHP) is a potential decision making method in management that can be used in project management as well. Lack of productivity is perhaps the number one problem confronting in the construction industry. There are numerous factors which affect the productivity of a construction project, so it is necessary to find out the critical factors giving birth to productivity. In this paper, construction productivity is taken as example for the demonstration of the AHP application to find out the critical productivity factor in which the Level 1 is taken as selection of critical productivity factor, Level 2 as construction parties and Level 3 as productivity factors group. The outcome of this study is beneficial to the entire constructional professionals for applying the AHP.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2002.11a
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• pp.59-62
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• 2002

Wavelength selection and prediction algorithm for determining hematocrit are investigated. A model based on the difference in optical density induced by the pulsation of heart beat is developed by taking approximation of Twersky's theory on the assumption that the variation of blood vessel size is small during arterial pulsing[1]. A device is constructed with a five-wavelength LED array as light source. The selected wavelengths are two isobestic points and three in compensation for tissue scattering. Data are collected from 549 out-patients who are randomly grouped as calibration and prediction sets. The range of percent hematocrit was 19.3∼51.8. The ratio of the variations of optical density between systole and diastole at two different wavelengths is used as a variable. We selected several such variables that show high reproducibility among all variables. Multiple linear regression analysis is made. The relative percent error is 8% and the standard deviation is 3.67 for the calibration set. The relative % error and standard deviation of the prediction set are 8.2% and 3.69 respectively. We successfully demonstrate the possibility of non-invasive hematocrit measurement, particularly, using the wavelengths below 1000nm.

• International Journal of Computer Science & Network Security
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• v.21 no.11
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• pp.301-311
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• 2021

The technological advancements of the last two decades directed the era of the Internet of Things (IoT). IoT enables billions of devices to connect through the internet and share their information and resources on a global level. These devices can be anything, from smartphones to embedded sensors. The main purpose of IoT is to make devices capable of achieving the desired goal with minimal to no human intervention. Although it hascome as a social and economic blessing, it still brought forward many security risks. This paper focuses on providing a survey of the most commonly used application layer protocols in the IoT domain, namely, Constrained Application Protocol (CoAP), Message Queuing Telemetry Transport (MQTT), Advanced Message Queuing Protocol (AMQP), and Extensible Messaging and Presence Protocol (XMPP). MQTT, AMQP, and XMPP use TCP for device-to-device communication, while CoAP utilizes UDP to achieve this purpose. MQTT and AMQP are based on a publish/subscribe model, CoAP uses the request/reply model for its structuring. In addition to this, the quality of service provision of MQTT, AMQP, and CoAP is not very high, especially when the deliverance of messages is concerned. The selection of protocols for each application is very a tedious task.This survey discusses the architectures, advantages, disadvantages, and applications of each of these protocols. The main contribution of this work is to describe each of the aforementioned application protocols in detail as well as providing their thorough comparative analysis. This survey will be helpful to the developers in selecting the protocol ideal for their system and/or application.

• Geotechnical Engineering
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• v.12 no.6
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• pp.185-198
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• 1996

EPS is increasingly used as a filling material in soft ground. The beneficial effects of the use of EPS derive from minimizing the stress increment, which, in turn, increases the bearing capacity and reduces the settlement. EPS can also be used as a backfill material for retaining walls and abutments to reduce the horizontal earth pressure. However, there is no rational application for the selection of the EPS fill which is essential to the selection of the filling configuration and the settlement calculation. In this paper, therefore, the nonlinear numerical model developed from the results of triaxial compression tests is applied to the construction of EPS and verified through the comparison between the prediction and in-situ measurements.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.1 s.120
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• pp.88-93
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• 2007

Since the 1990s, the application of Kentucky bluegrass cultivars has increased in newly-constructed Korean golf courses as opposed to the previously-used zoysiagrass. However, there have been few reports studying the selection and characterization of these Kentucky bluegrass cultivars under Korean weather conditions. A total of 12 Kentucky bluegrass cultivars were tested for their adaptability in environmental stresses during summer conditions in Korea in order to select the best Kentucky bluegrass cultivars for use in Korean golf courses. This study found that two Kentucky bluegrass cultivars ('Midnight' and 'Bluestone') maintained their green throughout the summer season and had a high degree of root density, as compared to the other cultivars tested. These two cultivars also had a good rate of coverage in the early growth period. These characteristics make them suitable for application on sports fields and golf courses, which receive many divots and the frequent replacement of turfgrass sod caused by both biotic and abiotic stress. Two other cultivars, the 'Ginney' and 'Nuglade', also displayed good visual quality and high rate of coverage under summer conditions. In conclusion, the 'Midnight' and 'Bluestone' cultivars performed well in areas including the maintenance of their green color, the number of roots and the rate of coverage during the summer months. These characteristics are necessary for golf courses sports fields, which receive many divots and requirethe frequent replacement of turfgrass. further research on a range of Kentucky bluegrass cultivars, including a sensitivity test for many pathogens and recovery rates from a variety of stresses, is required in the near future.

• Journal of KIISE:Information Networking
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• v.35 no.2
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• pp.112-119
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• 2008

Today, A matter of concern of home network technology increase. The standard of communication between home network devices are required. IEEE 802.1 AVB(Audio/Video Bridging) specifies transmission method for time-sensitive data between these devices using Ethernet in bridged local area networks. IEEE 802.1 AVB and IEEE 1588 PTP(Precision Time Protocol) have various message type for grandmaster selection and synchronize the devices. These messages bring on complexity protocol. We propose a method that uses Single TimeSync frame in order to the problem. Our proposal is appropriate process complexity and low transmission delay for home network by using the TimeSync frame. Furthermore, after all devices are adjusted to the single TimeSync frame, a resource reservation, a forwarding and queueing rule are needed for a time-sensitive application.

• Journal of Arbitration Studies
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• v.18 no.2
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• pp.33-54
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• 2008

The KCAB enacted their new international arbitration rules(the KCAB rules) in 2007 wheres The CIETAC revised their arbitration rules(the CIETAC new rules) in 2005. This article investigates some practical problems on both rules respectively and helps trading companies to proceed arbitration by these rules. This study finds some problems as follows. There are the following problems in KCAB rules. First, application fee is too expensive fee. So KCAB should cut down their application fee. Second, if there is no agreement on number of arbitrators, the arbitration is processed by sole arbitrator. But it is very difficult for sole arbitrator to process international arbitration due to characteristics of international arbitration such as complexity of case and a large sum of claim. Third, a period of selection of arbitrator is long. In view of developing of communication means, this period is needed more short. In the meantimes, there are the following problems in CIETAC rules. First, though the CIETAC new rules enlarges the right of parties autonomy such as selection of arbitration rules or revise of it, China arbitration Act stipulates a institute arbitration which restrict partie's autonomy. Second, if there is no agreement on arbitrators, the CIETAC appoints chair of tribural in three arbitrators ion or sole arbitrators. is processed by sole arbitrator. Third, a draft of arbitral award is checked by the CIETAC in advance. Especially, the two latter problems is possible for foreigners to have doubts of fairness of CIETAC arbitration. Becuase the CIETAC is not a complete independent private institution. Consequently, I suggest that Korean trading companies should examine problems of these two arbitration rules carefully, and select a most appropriate rules for settlement of their disputes with Chines companies.

• Journal of Soil and Groundwater Environment
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• v.12 no.1
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• pp.44-52
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• 2007

This study reviewed the overall process of application of contaminant fate and transport model as part of risk assessment. Site characterization and establishment of a conceptual model prior to establishing or selecting a appropriate model were described. Types of models, model selection guidance, and generic site conditions for model application were presented, the process of model calibration, validation, and sensitivity analysis were reviewed. Objectives of modeling should be defined before model selection, and the complexity of selected models should balance the quantity and quality of available input data with the desired model output. If model output is highly sensitive to an assumed or default value of input parameter, or fate and transport models cannot be adequately calibrated or validated, consideration should be given to other options such as using measured data or using another model.