• KIEAE Journal
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• v.1 no.1
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• pp.35-43
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• 2001

The VOC, which were detected from the newly built house, exist as a certain number of types according to the characteristics of the change of VOC concentration indoors. In this paper, we aim to divide the VOC into types so that those with similar characteristics of the transition of their concentration are in the same group and select the representative compound according to each classified type, and to verify these processes statistically in order to verify and propose new method creating the representing index of the VOC concentration in indoor which is used in evaluation of the degree of air pollution. As a result, the characteristic of the change of VOC concentration in the indoor can be divided into three types. Type1; the group in which the concentration is relatively high right after the completion of the house, and then decreases rapidly. Type2; the group in which the concentration is relatively low right after the completion of the house, and then although it shows the tendency of increasing and decreasing repeatedly, it decreases overall. Type3 is the group, which show only one peak at a certain time during the measuring period. As the method like this was verified to have the statistical significance, the Ethylbenzene was selected as the representative compound of type1, and Styrene was selected as that of type2. Moreover, if considering transition of the VOC from the point of similarity, the research method of making the classification and the selection of the representative compound in this study are said to be significant method.

• Journal of Environmental Policy
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• v.4 no.1
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• pp.69-91
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• 2005

In order to accurately evaluate the distribution and emission characteristics of volatile organic compounds(VOCs) produced in the landfill environment, we conducted a series of field campaign to measure VOC emissions from a total of eight landfill sites located all across the Korean Peninsula. During the field measurements made from Sept. 2000 to Dec. 2004, we investigated VOC emission characteristics from 1 large scale, 5 mid scale, and 2 small scale landfill sites. The results from our 4-years study is used to provide valuable information for the management of landfill facilities in Korea. If annual emission rates of VOC are compared in terms of toluene, the magnitude of its emission differed between the closed and active landfills. Whereas closed landfills show emission rates from a few tens to 500g/yr, those of active ones were recorded as 1,000 to 40,000g/yr.

• Journal of Korean Society for Quality Management
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• v.32 no.1
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• pp.75-91
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• 2004

The Internet has produced a great variety of VOC data. However, they are hardly helpful for CRM because they are not integrated with VOC data of the related businesses yet. This paper has set up a system for the said VOC data to actually become helpful for CRM The system has two aspects. From the aspect of products, the customers' needs for products will be analyzed to produce what they actually want. From the aspect of customers, on the other hand, decent relationships with them shall be maintained constantly by thoroughly analyzing all the related data. The analyses on both of these aspects have the advantage of maximizing customer satisfaction by active CRM that makes us recognize what customers prefer, or complain of in advance and then provide them with tailor-made service.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2001.11a
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• pp.299-302
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• 2001

• KIISE Transactions on Computing Practices
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• v.22 no.1
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• pp.50-55
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• 2016

To attain an understanding of customers' opinions or demands regarding a companies' products or service, it is important to consider VOC (Voice of Customer) data; however, it is difficult to understand contexts from VOC because segmented and duplicate sentences and a variety of dialog contexts. In this article, POS (part of speech) and morphemes were selected as language resources due to their semantic importance regarding documents, and based on these, we defined an LSP (Lexico-Semantic-Pattern) to understand the structure and semantics of the sentences and extracted summary by key sentences; furthermore the LSP was introduced to connect the segmented sentences and remove any contextual repetition. We also defined the LSP by categories and classified the documents based on those categories that comprise the main sentences matched by LSP. In the experiment, we classified the VOC-data documents for the creation of a summarization before comparing the result with the previous methodologies.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.3
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• pp.325-336
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• 2006

The presence of volatile organic compounds (VOC), produced and released from both anthropogenic and natural sources, can accelerate the degradation of air quality in the surrounding area. In this study, we investigated the emission concentrations of VOC based on a total of 115 sample analysis made from 47 companies (representing 17 types of industry) at the Ban Wall industrial complex (Jun. 2004 to Jan. 2005). Through a statistical analysis of these measurement data, we inspected the emission characteristics of VOC in relation with industrial type and processing unit. When these data were compared each other, toluene was found to record the highest value of 423 ppb followed by ethylbenzene (68.3 ppb), m, p-xylene (43.6 ppb), o-xylene (27.2 ppb), styrene (23.9 ppb), and benzene (16.4 pub). In addition, by converting these VOC concentration data into malodor intensity, we attempted to account for their distribution patterns in terms of relative contribution to the malodor formation. The results of odor intensity conversion generally indicated that the odor intensities of individual VOC do not exceed the degree of 1. When our VOC results were compared against other odorous compounds measured concurrently, the results were highly contrasting each other. Despite relative insignificance as odorous compounds, these VOCs are generally found ubiquitously and in abundant quantities in this strong source area.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.8
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• pp.518-527
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• 2014

This study is to estimate the learning curve based on the consequences of reduced voice of customer from each telecommunication service products. We used Exponential Decay Model, which is the most popular among the learning curve models. We attempted to add how VOC changes in accordance with seasonal factors, human resource input, application of software, and the investment. The results of the empirical analysis of each service product as follows: First, as learning curve, customer complaints decreased. Second, human resource input, Network fault make increase or decrease customer complaints(VOC). Third, even though increasing the customer's quality of experience, VOC would not decrease due to service paradox.

• Journal of the Korean Society of Visualization
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• v.9 no.2
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• pp.54-60
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• 2011

This paper is a basic study on volatile organic compounds(VOC) recovery system in a crude oil carrier. VOC is easily evaporated in cargo tankers during loading and transportation of crude oil, causes serious environmental contamination and a huge economic loss. An ejector system is designed to mix VOC gas into crude oil flow to reduce VOC concentration. Detail two-phase flow inside the ejector is simulated using a commercial CFD code. To verify the numerical prediction, a scale-down experiment is conducted. Instead of crude oil and VOC, water and air are used as the working fluids. Flow characteristics and main parameters are obtained by two-phase flow visualization and PIV measurements. Air volume flow rate induced by the ejector is compared with respect to the volume flow rate of water using experimental and numerical results. Overall performance of the two-phase ejector predicted by the CFD simulation agrees well with that of the experiment.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.05a
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• pp.579-587
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• 2003

A lot of VOCs that is noxious ate exhausted at drying process of enamel coating device. This VOC gas can be incinerated perfectly through catalytic combustion, and heat that is occurred in incineration process ran be again used in drying process. By using VU catalytic combustion technology, in this study, we developed a enamel coating machine that have an excellent environment improvement and energy saying effect. As basic research for this development characteristics ana performance of catalytic combustion for VOC gas was evaluated and numerical analysis for drying oven was calculated. According to the result, VOCs combustion characteristics of metal form catalysis was excellent in high temperature, and it was seen that enamel coating machine should be designed as a precious controllable structure of recirculating supply rate and suction rate.

• Journal of Korea Society of Digital Industry and Information Management
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• v.11 no.4
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• pp.13-24
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• 2015

Customer complaints handling helps organizations to retain existing customers and attract new customers, as well. As Voice of the Customer (VOC) is one of the main sources of customer complaints, many organizations utilize VOC to enhance customer satisfaction. Effective management of VOC has been proved as one of the best ways to maintain organization's brand image and reputation. In spite of its importance, little has been reported on the utilization of VOC to detect faults in a telecommunication industry. In this paper, association rule mining based on VOC is used to identify root fault causes of a telecommunications network. To do that, VOC of a Communication Service Provider has been collected first. Then, association rule mining has also been conducted with various support and confidence levels. As a result, root fault causes of the telecommunications network can be identified. It is expected that this study can be used as a basis for decisions about customer satisfaction management such as preventive maintenances or reduction of the customer maintenance cost.