• 전자공학회논문지S
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• 제34S권6호
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• pp.21-29
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• 1997

In this paper, we propose a new approach for recovering 3-D shape and extracting the reflectance properties of surface from intensity images. Photometric stereo method(PSM) is genrally based on the direct illumination. In this paper, the reflectance function is derived by interoduceing the indirect diffuse illumination in PSM and then applied to hybrid reflectance model which consists of two components; the lambertian and the specular reflectance. Under the hybrid reflectance model and the indirect diffuse illumination circumstance, the reflectance properties of sample surface can be extracting by normal sampler and then 3-D shape of an object can be recovered based on extracting reflectance properties. This method is rapid because of using the reference table and simplifies the restriction condition about the reflectance function existing in prior studies. Th erecovery efficiency in our method is better than that in prior studies. Also, this method is applied to various types of surfaces by defining general reflectance function.

• 한국통신학회논문지
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• 제21권2호
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• pp.301-312
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• 1996

A new approach is presented for recovering the 3-D shape from shading image. Photometric Stereo Method (PSM) is generally based on the direct illumination. In this paper, the reflectance function is derived by introduceing the indirect diffuse illumination in PSM and then applied to hybrid reflectance model which consists fo two components; the Lambertian reflectance and the speclar reflectance. Under the hybrid reflectance model and the indirect diffuse illumination circumstances, the 3-D shape of object can be recovered from the suface normal vector extracted from the surface roughness, the surface reflectance ratio, and the intensity value of a pixel. This method is rapid because of using the reference table and simplifies the restriction condition about the reflectance function existing in prior studies. The recovery efficiency in our method is better than that in prior studies. Also, this method is applied to various types of surfaces by defining general reflectance function.

• 한국식생활문화학회지
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• 제37권4호
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• pp.335-344
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• 2022

The study was aimed to investigate the operational meal costs by kindergarten size in Seoul and to analyze recognition for optimal meal prices. A survey (31.6% recovery rate) was conducted on all kindergartens (779 kindergartens) in Seoul on April 2021 using descriptive analysis, t-test, and dispersion method. A price sensitivity measurement (psm) method was used to determine optimal meal prices. Result showed an average food cost for kindergartens of 2,647 won, an average labor cost of 605 won, an average operating cost of 146 won, and the total meal cost of 3,506 won. Total meal cost decreased with increasing kindergarten size (p<0.001). On the other hand, kindergartens with more students decreased the ratio of food cost to total meal cost, and operating cost and labor costs (p<0.001) increased. The optimal price of kindergarten operators' meal cost (OPP) was KRW 3,673. Furthermore, the analysis showed the sensitivity of operators' meal costs to kindergarten size was insignificant.

• 인간식물환경학회지
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• 제22권5호
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• pp.525-539
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• 2019

Much research has been conducted on user behavior by taking surveys and interviews to plan the green space effectively. However, there is a limitation in understanding detailed user characteristics such as personalities and values. This study applied the Persona-based Scenario Method (PSM) to Hongneung Experimental Forest to understand the detailed needs and behaviors of the users in the forest recreation area. The PSM is a user experience modeling technique, which tries to understand the users by describing the type of users as real people. This study 1) extracts the factors of visitor recreation activities in Hongneung Experimental Forest based on the results of the survey, 2) develops user personas based on the results of survey and comes up with activity factors, and 3) designs user scenarios. As a result of applying the PSM, 64 factors of visitor activities were derived from the observation survey in 14 sites of Hongneung Experimental Forest and 25 key factors of visitor activities were chosen through observer's brainstorming. Second, three types of personas were developed considering the key factors and the results of user characteristics with quantitative and qualitative analysis. Lastly, context scenarios were designed by applying the key factors of visitor recreation activities to the persona model. We identified the design problems of the space and design requirements through the scenarios. This study has significance in that it takes an approach from the user perspective and was applied to the forest recreation area, which was mainly used in product design. The developed personas could be used for deriving design elements and setting the direction for planning considering detailed needs, behaviors and characteristics of users.

• ETRI Journal
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• 제34권2호
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• pp.268-271
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• 2012

The high peak-to-average power is one of the main drawbacks in OFDM systems. This letter proposes a partial shift mapping (PSM) method for peak power reduction in OFDM systems. By utilizing the properties of the discrete Fourier transform, the proposed method generates a set of candidate signals without additional complex multiplication and selects the one with minimum peak power for transmission. Analyses and simulations confirm that the PSM method achieves satisfactory peak power reduction performance and low complexity compared with other kindred methods, for example, selected mapping and partial transmit sequences.

• 한국멀티미디어학회논문지
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• 제10권4호
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• pp.450-461
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• 2007

본 논문에서는 묵음 억제 기술이 지원되는 VoIP 트래픽에 비 실시간 트래픽을 위한 전원 절약 모드와 실시간 트래픽을 위한 전원 절약 모드를 동시에 적용하는 혼합 전원 절약 모드를 제안한다. 제안한 방법은 사용자들이 통화를 하고 있는 구간에서는 제 2종 전원 절약 모드를 적용하고 상호 침묵 구간에서는 BTE(binary truncated exponent) 알고리즘 혹은 PSID (probabilistic sleep interval decision) 알고리즘을 적용하여 휴지 구간 (sleep interval)의 길이와 위치를 결정한다. 제안한 알고리즘의 성능을 평가하기 위하여 평균 버퍼링 지연 시간, 단말의 에너지 소비 효율, VoIP 패킷의 손실률 등을 고려한다. 시뮬레이션 결과로부터 혼합전원 절약 모드는 VoIP서비스의 최대 허용 패킷 손실률을 만족시키면서 단말의 에너지 소비를 제 2종 전원 절약 모드보다 25%까지 낮출 수 있다는 것을 보여준다.

• 디지털산업정보학회논문지
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• 제16권2호
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• pp.117-128
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• 2020

The aim of this study was to examine price sensitivity of industrial products purchased via a group buying system and how industrial products for a group buying system differ from general industrial products, and then identify the major factors in selecting products and the important determinants in purchasing industrial products for school foodservices. The survey was conducted with 250 dietitians (teachers) in Gyeonggi-do Province, who were using industrial products for a group buying system and general industrial products. A paired t-test showed a difference in satisfaction between industrial products for a group buying system and general industrial products by factors, while statistically significant differences were found for red pepper paste, fermented soybean paste and soy sauce in all nine satisfaction factors, including product quality, packaging state, labeling, hygiene, item diversity, specification diversity, price appropriateness and supply. Moreover, analyzing price sensitivity for industrial products for a group buying system, using the PSM method with respect to the issue of high price, showed that the respondents considered that the current unit purchase prices were high for all items investigated. This study suggests that schools would purchase more industrial products for a group buying system, when the pricing of the products are considered with the purchase intention of dietitians (teachers).

• 정보처리학회논문지D
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• 제15D권2호
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• pp.187-196
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• 2008

새로운 패러다임의 시스템 개발 접근 방법은 OMG(Object Management Group)에서 MDA(Model Driven Architecture)로 표준화하고 있다. MDA의 핵심 기술은 모델 중심의 시스템 구현을 위한 기술 구조를 정의하는 것으로 시스템의 설계 및 명세에 대한 구현 기술을 플랫폼 독립적 모델(PIM : Platform Independent Model)로 설계한 후, 구현 환경에 적합한 플랫폼 종속적 모델(PSM : Platform Specific Model)로 설계하여 구현환경에 맞는 언어로 변환하는 기술이다. MDA의 핵심인 MOF(Meta-Object Facility), UML, XMI(XML Metadata Interchange), CWM(Common Warehouse Metamodel) 표준 등이 포함된다. MDA 지원 자동화 툴들은 위의 정보들을 갖고 변환 작업을 수행한 후 실행 가능한 시스템으로 생산해 내는 것이다.[1] 본 논문에서는 MDA기반 접근 방법을 적용하여 학사관리 시스템을 설계 및 구현하고, MDA기반 접근 방법에 대한 모델링의 중요성을 강조하였다. 또한 소프트웨어를 효율적으로 개발하는 방법을 제시하여 플랫폼 독립적 모델(PIM)로 작성하고, 플랫폼 종속적 모델(PSM)을 J2EE 플랫폼 기반의 EJB(Enterprise Java Beans)로 변환하는 과정 등을 제시하였다. MDA를 지원하는 자동화 툴 및 편집기(Together Architect 2006 for Eclipse, Edit plus 2)와 데이터베이스 모델링 툴(ER/WIN 4.1)을 사용하여 시스템 설계 및 구현을 하였으며, 전통적 개발 프로세스와 MDA 기반 개발 프로세스에 대한 유효성 분석 결과를 제시하였다.

• 한국산학기술학회논문지
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• 제4권1호
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• pp.22-26
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• 2003

Attenuated PSM lithography 공정에서 overlay margin 확보 및 side-lobe 제거를 위해 기존의 Cr shield 방식의 단점인 복잡한 mask 제작공정과 구조를 단순화하기 위한 방법으로 scattering bar 방식을 제안하였다. Scattering bar는 Cr 보조패턴처럼 완전히 빛을 차단하는 것이 아니라 약간의 빛을 투과시켜 보강된 intensity를 상쇄하므로 side-lobe를 억제하는 방법으로 metal pattern을 생성할 때 scattering bar도 동시에 만들어 mask제작에 필요한 공정횟수를 줄이고 mask구조 역시 단순하게 한다 그리고 동시에 DOF(depth of focus)를 향상시킨다. Background clear pattern의 경우에 발생하는 side-lobe도 scattering bar를 이용하여 효율적으로 제거되었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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• pp.209-212
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• 2002

As the mask design rules get smaller, the probability of the process failure becomes higher doc to the narrow overlay margin between the contact and metal interconnect layers. To obtain the minimum process margin, a tabbing and cutting method Is applied with the rule based optical\ulcorner proximity correction to the metal layer, so that the protection to bridge problems caused by the insufficient space margin between the metal layers can be accomplished. The side-lobe phenomenon from the attenuated phase shift mask with the tight design rule is analyzed through the aerial image simulation for test patterns with variation of the process parameters such as numerical aperture, transmission rate, and partial coherence. The corrected patterns are finally generated by the rules extracted from the side-lobe simulation.