구독형 음원 스트리밍 플랫폼 고객의 구독의도 및 고객만족에 대한 실증 연구

이상훈,김서영,박민서,김연성,Lee, Sang Hoon,Kim, Seo Young,Park, Min Seo,Kim, Youn Sung 한국품질경영학회 2022 품질경영학회지 Vol.50 No.3

Purpose: The purpose of this study was to explore and examine the factors influencing customer satisfaction and subscription intention in order to propose useful implication regarding subscription economy model. Methods: This study adopts the extended Unified Theory of Acceptance and Use of Technology model (UTAUT2) as the theoretical framework. On the basis of literature review, this study suggested 9 related hypothesis. To examine the hypothesis proposed, the study designed surveys with 32 questions and 456 answers were collected for the analysis. The study adopted a structural equation model and path analysis, using AMOS and SPSS programs. Results: The results of this study are as follow: All hypothesis except performance expectancy and effort expectancy have significant influence on customer satisfaction. Performance expectancy and effort expectancy have no significant influence on customer satisfaction and facilitate condition is significant but negatively associated with customer satisfaction. Conclusion: Result of this study is expected to suggest data regarding subscription economy and customer satisfaction for business with subscription model. In detail the result implies that highly sophisticated curation system would create more customer satisfaction and subscription intention rather than how a subscription-based platform is easily used. Moreover, curation system of subsription-based music platform should function with high accuracy on recommendation in a creative visual form in order to gain comparative advantage while most platforms have built own curation service.

데이터 분포를 고려한 연속 값 속성의 이산화

이상훈,박정은,오경환,Lee, Sang-Hoon,Park, Jung-Eun,Oh, Kyung-Whan 한국지능시스템학회 2003 한국지능시스템학회논문지 Vol.14 No.7

본 논문에서는 특정 매개변수(parameter)의 입력 없이 속성(attribute)에 따른 목적속성(class)값의 분포를 고려하여 연속형(continuous) 속성 값을 범주형(categorical)의 형태로 변환시키는 새로운 방법을 제안하였다. 각각의 속성에 대해 목적속성의 분포를 1차원 공간에 사상(mapping)하고, 각 목적속성의 밀도, 다른 목적속성과의 중복 정도 등의 기준에 따라 구간을 군집화 한다. 이렇게 생성된 군집들은 각각 목적속성을 예측할 수 있는 확률적 수치에 기반한 것으로, 각 속성이 제공하는 정보의 손실을 최소화 하는 이산화 경계선을 갖고 있다. 제안된 데이터 이산화 방법의 향상된 성능은 C4.5 알고리즘과 UCI Machine Learning Data Repository 데이터를 사용하여 확인할 수 있다. This paper proposes a new approach that converts continuous-valued attributes to categorical-valued ones considering the distribution of target attributes(classes). In this approach, It can be possible to get optimal interval boundaries by considering the distribution of data itself without any requirements of parameters. For each attributes, the distribution of target attributes is projected to one-dimensional space. And this space is clustered according to the criteria like as the density value of each target attributes and the amount of overlapped areas among each density values of target attributes. Clusters which are made in this ways are based on the probabilities that can predict a target attribute of instances. Therefore it has an interval boundaries that minimize a loss of information of original data. An improved performance of proposed discretization method can be validated using C4.5 algorithm and UCI Machine Learning Data Repository data sets.

남극 남쉐틀랜드 북부 대륙주변부 및 남스코시아해 지역의 고해상(3.5 kHz)음향 특성

이상훈,진영근,김규중,남상헌,김예동,Lee, Sang-Hoon,Jin, Young-Keun,Kim, Kyu-Jung,Nam, Sang-Heon,Kim, Yea-Dong 한국해양과학기술원 2003 Ocean and Polar Research Vol.25 No.4

High-resolution (3.5 kHz) subbottom profiles were analyzed in order to reveal sedimentation pattern of late Quaternary in the northern South Shetland continental margin and the South Scotia Sea, Antarctica. On the basis of clarity, continuity and geometry of surface and subbottom echoes together with seafloor topography, high-resolution echo characters are classified into eight echo types which represent rock basements (echo type III-1), coarse-grained subglacial till or moraine (echo type I-1), slides/slumps (echo type IV), debris-flow deposits (echo types II-3 and III-2), and bottom-current deposits (echo types I-2, II-1 and II-2). Subglacial till or moraine (echo type I-1) is mostly present in the lower continental shelf and upper continental slope of the northern South Shetland continental margin, which changes downslope to slides/slumps (echo type IV) and debris-flow deposits (echo types II-3 and III-2) in the middle to lower continental slope. This distribution suggests that the continental slopes of the northern South Shetland continental margin were mostly affected by downslope gravitational processes. Further downslope, bottom-current sediments (echo type I-2) deposited by the southwestward flowing Antarctic Deep Water (ADW) occur at the South Shetland Trench, reflecting an Interaction between mass flows and bottom currents in the area. In contrast to the northern South Shetland continental margin, the South Scotia Sea is dominated by bottom-current deposits (echo types II-1 and II-2), indicating that the sedimentation was mostly controlled by the westward flowing ADW. Flow intensity of the ADW has increased in the relative topographic highs, forming thin covers of coarse-grained contourites (echo type II-1), whereas it has decreased in the relative topographic lows, depositing thick, fine-grained contourites (echo type II-2). The poor development of wave geometry in the fine-grained bottom-current deposits (echo type II-2) is suggestive of the unsteady nature of the ADW flow.

Hyperbolic Tangent 검파방식에서 Null zone을 이용한 적응 병렬 간섭제거기

이상훈,김남,Lee, Sang-Hoon,Kim, Nam 대한전자공학회 2001 電子工學會論文誌-TC (Telecommunications) Vol.38 No.3

In the DS/CDMA mobile communication systems, the parallel interference canceller is used in order to reduce the multiple access interference and the multipath fading. It is needed the accurate interference estimate in the multistage parallel cancellation. In this paper, the adaptive cancellation method and the new tentative decision device arc proposed and the performance is analyzed. The adaptive cancellation method uses the normalized least mean square(NLMS) algorithm to calculate the weight adaptively, and new tentative decision device uses the hyperbolic tangent decision with null zone. Computer simulation shows that the proposed scheme has the improved performance and the number of user is increased 48% compared with the conventional receiver. DS/CDMA방식의 이동통신 시스템에서 다중접속 및 다중경로 페이딩 간섭을 제거하기 위하여 비교적 구조가 간단한 병렬 간섭제거기가 이용된다. 다단계로 구성되는 병렬 간섭제거방식에서 다중접속 간섭의 제거 성능을 향상시키기 위하여 간섭의 정확한 추정이 필수적이다. 본 논문에서는 제거성능의 향상을 위해 NLMS(Normalized Least Mean Square)알고리즘으로 가중치(weight)를 계산하는 적응 제거방식과 시험 검파기로서 HT(Hyperbolic Tangent)검파방식에 NZ(Null Zone)을 이용하는 새로운 검파방식을 제안하고 모의실험을 통하여 그 성능을 분석하였다. 모의실험 결과 제안하는 방식이 비트오율 $2{\times}10^{-2}$에서 기존의 제거기에 비해 사용자수가 약 48%정도 증가하는 개선된 성능을 얻었다.

SFF/SFP 장 송수신기용 TO-can 패키지 주파수 응답 향상 연구

이상훈,정현도,구본조,한상국,Lee Sang-Hoon,Jung Hyun-Do,Koo Bon-Jo,Han Sang-Kook 한국통신학회 2004 韓國通信學會論文誌 Vol.29 No.1A

본 논문은 SFF/SFP 광 송수신기에 사용되는 TO-38 패키지의 대역폭 향상을 위해 여러 구조적 변수를 변화시켜 최적화하여 3dB대역폭의 성능향상을 제안하였다. 먼저 실험을 통해 PIN PD 칩에 인가된 바이어스에 따른 캐패시턴스 값을 구하였으며 TO-can 패키지의 주파수 응답을 측정하여 3.5GHz의 3dB 대역폭을 얻었다. 또한 3차원 시뮬레이션으로 측정치와의 주파수 응답 특성의 일치를 재확인하였다. 더 나은 주파수 응답을 얻기 위해 TO-can 패키지 여러 물리적 구조 변수를 변화시켜 최적화시킨 TO-38 패키지는 3dB대역폭 15GHz의 아주 우수한 성능향상을 보였으며 이는 10Gbps대의 bit rate 성능을 만족할 수 있는 SFF/SFP 광 송수신기 모듈에 적용이 가능하다. We propose the optimum TO-can package design in SFF/SFP optical transceiver modules to improve 3dB-bandwidth. The frequency response of TO-38 package is measured and compared to simulation where the 3dB-bandwidth was 3.5GHz. For a higher operating bandwidth (>15GHz), the new optimized physical geometries of TO-can package such as bonding-wire, lead and material was suggested. The optimal result of simulation shows that TO-can package can be used at a higher bit rate optical module of 10Gbps.

중완(中脘)$(CV_{12})$, 비유(脾兪)$(BL_{20})$ 침자극(鍼刺戟)이 고지방식이(高脂肪食餌)에 의한 당뇨병유발(糖尿病誘發) 흰쥐의 혈청(血淸)Glucose 농도(濃度)와 지질구성(脂質構成)에 미치는 영향(影響)

이상훈,이준무,Lee, Sang-Hoon,Lee, Joon-Moo 경락경혈학회 2004 대한침구의학회지 Vol.21 No.1

Objective : This study is effects of Jungwan$(CV_{12})$ and Bisu$(BL_{20})$ acupuncture on serum glucose and lipid composition were investigated in high fat diet induced diabetic rat. Results : Plasma glucose, free fatty acids and $\beta-lipoprotein$ concentration showed a high reduction in acupuncture groups compared to those of control group and in the acupuncture groups, Jungwan$(CV_{12})$ acupuncture groups showed a low values than Bisu$(BL_{20})$ acupuncture group. Plasma triglyceride and LDL-cholesterol concentration showed a tendency to decrease in the acupuncture groups, however these values showed no significantly different among acupuncture groups. Total cholesterol concentration showed a high reduction in acupuncture groups and in acupuncture groups, Jungwan$(CV_{12})$ acupuncture groups showed a lower values than Bisu$(BL_{20})$ acupuncture group. HDL-cholesterol concentration showed a higher values in all acupuncture groups than control group, however these values no significantly different in all acupuncture groups.

4.3 μm 파장 Optical Band-Pass Filter의 제작과 CO₂ 감도 특성

이상훈,김수현,김광호,Lee, Sang-Hoon,Kim, Soo-Hyun,Kim, Kwang-Ho 한국세라믹학회 2002 한국세라믹학회지 Vol.39 No.2

본 연구에서는 $CO_2$ 흡수단이 있는 4.3${\mu}m$ 파장대역의 광학 필터를 전자빔 증발 장치를 이용하여 Ge와 $SiO_2$ 박막을 다층으로 설계, 제작하였다. 제작된 Ge/$SiO_2$ 다층박막 필터는 기준파장에 대하여 반가폭(FWHM) 204nm, 투과율 58.2%, 금지대역에 대하여 5% 이하의 차단특성을 나타내는 협대역 투과필터 (narrow band-pass filter: BPF)특성을 나타내었다. 광학적 대역투과필터를 사용하여, FT-IR내에 감지실을 설치하여 단식 필터(KBr+BPF)와 복식필터(BPF+BPF)의 $CO_2$ 농도별 감도특성을 비교측정 하였다. 측정시 $CO_2$의 농도는 500ppm을 단위로 500∼5000ppm의 범위까지 관찰하였는데, 복식 필터는 단식 필터에 비해 투과율이 낮았지만, 우수한 감도 특성을 보였다. Optical Band-pass Filter(BPF) for the selected wavelength of 4300 nm was designed and fabricated on Si wager by alternately depositing Ge and $SiO_2$ thin layers by an electron beam evaporation technique. The fabricated BPF showed the optical transmittance characteristics of 58.2% with FWHM(Full Width at Half Maximum) of 204 nm at 4300 nm, but showed the transmittance less than 5% due to the reflectance over all the wavelength ranges except 4300 nm band. The $CO_2$ sensitivity of BPF was investigated with the transmittance as a function of $CO_2$ gas concentration using a sensing cell attached to FT-IR instrument. The transmittance of BPF was almost linearly decreased with increasing of $CO_2$ concentration in the range of from 500 to 5000 ppm. The sensing structure using double BPFs showed higher slop of transmittance vs $CO_2$ concentration, and thus higher gas sensitivity than that using a single BPF, even though the former had relatively lower transmittance.

국내육성 톨 페스큐 품종간 생육특성 및 종자생산성

이상훈,최기준,김기용,지희정,황태영,박형수,김종근,이기원,Lee, Sang-Hoon,Choi, Gi Jun,Kim, Ki-Yong,Ji, Hee Chung,Hwang, Tae Young,Park, Hyung Soo,Kim, Jong Gun,Lee, Ki-Won 한국축산환경학회 2014 한국축산시설환경학회지 Vol.20 No.4

A new tall fescue variety (Festuca arundinacea Schreb.) named Greenmaster and Purumi were. In this study, we evaluated the seed production of new tall fescue domestic varieties were cultivated in Korea. Agronomic aspects of tall fescue domestic varieties were determined using seed production and forage nutritive value of straw at the National Institute of Animal Science from 2013 to 2014. The heading date according to the varieties displayed differences and domestic varieties showed enhanced disease resistance. The harvested seed yields of Greenmaster was 35% higher as 1,664 kg/ha and it's also yield of straw higher than that of Fawn. However, the nutritive value of both varieties was similar. The dry matter yield of Pumumi was 25% higher as 11,080 kg/ha. Accordingly, developed a new variety of domestic tall fescue with excellent environmental adaptability, aiming to make contribution to the vitalization of the Korean grassland industry.

전리함 반응 함수의 직접 측정과 이를 이용한 방사선의 실제선량 분포측정

이상훈,조병철,김종훈,최은경,권수일,장혜숙,이병용,Lee Sang Hoon,Cho Byung Chul,Kim Jong Hoon,Choi Eun Kyung,Kwon Soo Il,Chang Hyesook,Yi Byong Yong 대한방사선종양학회 1997 Radiation Oncology Journal Vol.15 No.1

목적 : 전리함의 크기로 인한 공간 분해능의 문제로 나타나는 전리함 반응함수를 제거하여 실제 선량분포를 얻고자 하였다. 대상 및 방법 : 내경 5mm, 6.4mm 등 2개의 서로 다른 크기를 갖는 전리함들과 다이오드, 필름의 반응함수를 구하고, 동일한 방사선 조사면$(10\times20cm^2)$의 선량분포 프로파일을 측정하여, 각각 deconvolution 기법으로 보정한 후, 보절된 격과가 일치하는지 비교하였다. 결과 : 원통형 전리함의 반응함수와 선량분포를 측정하였고, 측정한 선량분포에서 반응 함수의 효과를 deconvolution방법으로 제거하여 실제 선량분포를 찾아내었다. 사용한 에너지는 최대 광자선 에너지 4MV, 6MV, 15MV였으며, 전 에너지 영역에 걸쳐 보정 된 결과가 일치하는 방향으로 변화하였으며, 분해능 증가 효과가 있었다. 결론 : deconvolution 방법으로 전리함 반응 함수의 효과를 제거했을 때, 여러 측정기를 이용하여 측정한 선량 프로파일의 결과가 일치하는 경향을 볼 수 있어서 deconvolution 방법을 통해 얻은 선량 프로파일을 임상적으로 응용할 수 있음을 알았다. Purpose : To obtain the actual dose distribution from measured data by doconvolution method using the measured ion chamber response function. Materials and Methods : The chamber response functions for 2 ionization chambers (diameter 5mm, 6.4mm) were measured. and dose Profiles were measured for $10{\times}20cm^2$ field size using two different detectors. The deconvolution of chamber response function from the measured data were performed for these Profiles. The same procedures were repeated for 4MV, 6MV and 1 SMV photon energies. Results : Different dose Profiles were obtained for the same field with the chambers which have the different response functions. Nearly the same results could be obtained with deconvolution for the profiles from various detectors. Conclusion : The effect of the chamber response function can be extracted by deconvolution method. Deconvolved dose profile using various ionization chambers gave better dose distributions. Technical improvements are needed for practical application.

견관절 주위 원발성 골 종양에서 사지 구제술의 종양학적 결과 및 기능적 평가

이상훈,유재호,오주한,서성욱,김한수,Lee, Sang-Hoon,Yoo, Jae-Ho,Oh, Joo-Han,Suh, Sung-Wook,Kim, Han-Soo 대한근골격종양학회 2002 대한골관절종양학회지 Vol.8 No.3

목적: 견관절 주위 원발성 골 종양 환자에서 시행한 사지 구제술의 종양학적, 기능적 결과를 평가하고자 하였다. 대상 및 방법: 1982년에서 2001년 사이에 견관절 주위 원발성 골 종양으로 본원에서 사지 구제술을 시행 받은 환자 중 추시 관찰이 가능한 2 9명을 대상으로 하였다. 평균 연령은 35세, 평균 추시 기간은 7년 1개월(1년 2개월~19년 9개월)이었고, 골육종 7예, 연골육종 14예, 방골성 골육종 1예, 혈관외피종 1예, 거대세포종 6예였다. 사지 구제술의 방법으로는 시멘트 충전술을 7예에서, 시멘트 주형 관절성형술 및 골수강내 정 삽입술을 10예에서, 종양 대치물 삽입술을 7예에서 이용하였으며, 5예에서는 절제만 시행하거나, 골이식, 관절 유합술 등을 실시하였다. 술 후 기능 평가는 근골격계 종양 학회(Musculoskeletal Tumor Society)의 상지 근골격계 종양 환자 기능 평가 방법을 이용하였다. 결과: 추시 도중 6예에서 국소 재발 하였고, 2예에서 폐 전이로 재발 하였고, 2예에서는 국소 재발과 폐전이가 모두 있었으며 3명이 사망하였다. 구제된 상지의 생존율은 최종 추시상 88.6%였으며, 재발이나 전이가 있을 경우 열등한 사지의 생존율을 보였다(p=0.012). 근골격계 종양 학회 기능 평가상 구제된 상지의 기능 점수는 평균 80%(24점, 18~30점)였다. 치료방법에 따른 기능 점수는 시멘트 충전술 86%, 시멘트 주형 관절성형술 및 골수강내 정 삽입술 71%, 종양 대치물 삽입술 83%점으로 시멘트 주형 관절성형술 및 골수강내 정 삽입술이 통계적으로 유의하게 좋지 않은 결과를 보여주었다(p=0.034). 합병증으로 요골 신경 마비와 액와 신경 마비가 각각 1예 있었으며, 생 비골 이식편의 이탈로 재수술을 받은 경우가 1예, 창상 감염이 1예 있었다. 결론: 견관절 주위 악성 골 종양과 거대 세포종의 치료에 있어서, 사지 구제술은 종양학적, 기능적으로 만족할 만한 결과를 얻을 수 있는 방법으로 사료된다. Purpose: The purpose of this study was to assess the oncologic results and functional outcomes of limb salvage surgery performed in patients of primary bone tumors of the shoulder girdle. Materials and Methods: Twenty-nine patients who underwent limb sparing resection for shoulder girdle neoplasm between 1982 and 2001 were analyzed. Follow up periods averaged 7 years and 1 month. Mean age of the patients was 35 (11~71) years. There were 14 males and 15 females. Primary malignant bone tumors of shoulder girdle (proximal humerus 21, scapula 3, both 1) were 23 cases; osteosarcomas 7, chondrosarcoma 14, parosteal osteosarcoma 1, hemangioendothelioma 1, and giant cell tumor of proximal humerus were 6 cases. Limb salvage surgery was performed by curettage and cementing in 7 patients, by cement molding arthroplasty in 10 patients, and by tumor prosthesis in 7 patients, by other method such as resection only, bone graft, arthrodesis in 5 patients. The Musculoskeletal Tumor Society functional rating system was used to assess functional outcomes. Results: One osteosarcoma and 2 chondrosarcoma patients died, and the survival of the salvaged limb was 88.6% at the final follow-up. There were 6 local recurrences, 2 lung metastases, 2 local recurrences and lung metastases. The functional outcome was 80%. There was statistically significant difference of functional results among the patients treated by cement filling (86%), cement molding arthroplasty and IM nailing (71%), and tumor prosthesis (83%). (p=0.034) There were three complications including 1 radial nerve palsy and 1 axillary nerve palsy, and 1 wound infection. Dislodgement of vascularized fibular graft in one patient was treated by internal fixation. Conclusion: Limb salvage surgery seems to be useful method to treat bone tumors of the shoulder girdle.