딥러닝 모델을 이용한 휴대용 무선 초음파 영상에서의 경동맥 내중막 두께 자동 분할 알고리즘 개발

최자영,김영재,유경민,장영우,정욱진,김광기,Choi, Ja-Young,Kim, Young Jae,You, Kyung Min,Jang, Albert Youngwoo,Chung, Wook-Jin,Kim, Kwang Gi 대한의용생체공학회 2021 의공학회지 Vol.42 No.3

Measuring Intima-media thickness (IMT) with ultrasound images can help early detection of coronary artery disease. As a result, numerous machine learning studies have been conducted to measure IMT. However, most of these studies require several steps of pre-treatment to extract the boundary, and some require manual intervention, so they are not suitable for on-site treatment in urgent situations. in this paper, we propose to use deep learning networks U-Net, Attention U-Net, and Pretrained U-Net to automatically segment the intima-media complex. This study also applied the HE, HS, and CLAHE preprocessing technique to wireless portable ultrasound diagnostic device images. As a result, The average dice coefficient of HE applied Models is 71% and CLAHE applied Models is 70%, while the HS applied Models have improved as 72% dice coefficient. Among them, Pretrained U-Net showed the highest performance with an average of 74%. When comparing this with the mean value of IMT measured by Conventional wired ultrasound equipment, the highest correlation coefficient value was shown in the HS applied pretrained U-Net.

가상 현실 기반 철강 공정 조업 교육 시스템

최자영,이진휘,김용수,김석,Choi, Ja-Young,Lee, Jin-Hwi,Kim, Yong-Soo,Kim, Seok 제어로봇시스템학회 2015 제어·로봇·시스템학회 논문지 Vol.21 No.8

This paper will introduce the development case study about virtual-reality-based operation training system for steel making process. Steel making process consist iron making process to create liquid steel, pig iron, by reduction process, steel making process to make molten steel by refining, continuous casting process to make slab, and rolling process to make final product like coil, plate. This steel making process deals with liquid and solid products, so facilities of steel making process are very various and complicated. In addition, according to various customer requirements, the recycle of facilities and recipes changing have been fast. So the training for skilled operators is very important point. In this paper, we develop steel making training system based virtual reality for training skilled operator. This system consists of virtual machine, virtual HMI, and virtual control panel. And for fitting the characteristics of each process and increasing the education effectiveness, we develop dynamic methods like the method of dynamic education system configuration, initial facilities setup operation education system, and etc.

직물디자인의 감성공학적 분석 방법론 연구

최자영 ( Ja Young Choi ),이현주 ( Hyun Joo Lee ),오대욱 ( Dae Wook Oh ),임춘성 ( Choon Seong Leem ) 한국감성과학회 1998 춘계학술대회 Vol.1998 No.-

본 연구에서는 감성공학적 분석 방법론을 고안하여 직물 디자인 분야에 적용하고 그 효용성을 규명하였다. 방법론을 개발하기 위한 기초자료로서 직물 디자인요소와 이와 관련된 감성어휘를 수집하고 직물디자인요소계층도를 구축하였다. 수립된 직물디자인요소계층도상의 디자인요소에 관한 상대적인 중요도를 조사하여 디자인 요소별 가중치를 산출하고, 특정 디자인에 대하여 총체적인 감성수준과 디자인 요소별 감성수준을 측정한다. 측정된 요소별 감성수준을 Analytic Hierarchy Process 기법으로 종합한 감성수준을 비교한 결과 높은 상관관계를 보였다. 이 분석 방법론은 사전정보와 기술요소정보를 유기적으로 결합한 기반이 될 수 있는 합리적, 과학적인 개발 방법론을 제시하였다는데 큰 의의를 갖는다.

논문(論文) : 엘레우시스와 아테네: 고대 그리스 폴리스의 정치적,지역적 연계의 유연성

최자영 ( Ja Young Choi ) 한국서양고대역사문화학회 2008 서양고대사연구 Vol.22 No.-

12 주간의 웨이트 트레이닝이 신체형태 및 구성에 미치는 영향

최자영(Choi Ja Young),김기진(Kim Ki Jin) 한국사회체육학회 2000 한국사회체육학회지 Vol.14 No.-

The purpose of this study is to examine the influence of weight training program to body shape and body composition of men and women. This study executed 12 weeks weight training program to 6 men and 6 women who are healthy, and then analyzed the data. In result of executing weight training program, there wasn't any significant change of body shape, but it was the significant reduction of body fat percentage (p<0.05). And there wasn't any significant change in all the adipose quantity and abdominal skinfold thickness. In conclusion, the weight training program is considered to be a desirable method which can prevent and cure obesity by reducing the percentage of body fat.

전 (前) 5 세기 아테나이 정치적 투쟁의 성격 - arete 의 분석을 중심으로 -

최자영(Ja Young Choi) 경북사학회 1981 복현사림 Vol.3 No.1

N/A

가상 현실 기반 철강 공정 조업 교육 시스템

최자영(Ja-Young Choi),이진휘(Jin-Hwi Lee),김용수(Yong-Soo Kim),김석(Seok Kim) 제어로봇시스템학회 2015 제어·로봇·시스템학회 논문지 Vol.18 No.1

This paper will introduce the development case study about virtual-reality-based operation training system for steel making process. Steel making process consist iron making process to create liquid steel, pig iron, by reduction process, steel making process to make molten steel by refining, continuous casting process to make slab, and rolling process to make final product like coil, plate. This steel making process deals with liquid and solid products, so facilities of steel making process are very various and complicated. In addition, according to various customer requirements, the recycle of facilities and recipes changing have been fast. So the training for skilled operators is very important point. In this paper, we develop steel making training system based virtual reality for training skilled operator. This system consists of virtual machine, virtual HMI, and virtual control panel. And for fitting the characteristics of each process and increasing the education effectiveness, we develop dynamic methods like the method of dynamic education system configuration, initial facilities setup operation education system, and etc.

중국의 기업 관행과 네트워크

최자영 ( Ja Young Choi ),이승철 ( Sung Cheol Lee ) 한국경제지리학회 2011 한국경제지리학회지 Vol.14 No.4

1978년 이후 중국은 시장 개방과 더불어 탈사회주의 경제 체제 전환을 통하여 고도의 경제성장을 이루었다. 특히, 새로운 자본주의 시스템의 도입을 통한 중국의 전환 경제(transitional economies)는 사회주의 체제 하에서 이루어졌던 기업 행위의 근본적인 양적 및 질적 변화를 가져왔다. 그럼에도 불구하고, 중국 기업은 기존 관행(existing practice)을 토대로 한 사적 네트워크(interpersonal networks)인 ``꽌시`` (guan xi)를 지속적으로 유지함으로서 새로운 산업 생산 조직 및 공간 질서를 형성하고 있다. 따라서 본 연구는 중국 특유의 사적 관계인 꽌시가 중국 기업의 사업 행위에 끼치는 영향을 검증하기 위하여 중국 기업의 꽌시 형성 메커니즘을 분석하였다. 중국 기업 네트워크에서 나타나는 꽌시의 특성은 크게 세 가지로 나타났다. 첫째, 기업 간 관계에서 꽌시는 기업 간 상호 호혜적 관계를 기반으로 한 상호 채무적 특성을 동시에 가짐으로서 기업 간 연계 및 기업 행위를 활성화 시키는 역할을 한다. 둘째, 중국 기업은 ``꽌시후`` 라는 ``꽌시 중개인`` (guanxi communicator)을 활용하여 기업 외부의 사적 네트워크를 내부화(internalization of personal networks) 함으로서 선천적 꽌시보다 후천적 꽌시에 많이 의존하는 것으로 나타났다. 즉, 사적 네트워크의 공식화(internalization of personal networks)를 통해 기업 연계의 효율성을 제고하고자 하였다. 마지막으로 기업 외 관계에서 기업과 정부의 꽌시는 불안정한 법 제도에 따른 리스크 방지 및 피해를 최소화하기 위해 형성되었다. 결론적으로 중국에서 꽌시 구축의 의미는 사적 네트워크의 활성화를 의미하며, 이를 통해 ``사회적 자본(social capital)``이 구축되어 거래비용의 감소, 운영상의 불확실성 감소, 정보비용 감소, 상황에 따른 리스크 감소, 경쟁위협 감소 등의 효과가 나타났다. China has gone through rapid economic growth due to transitional economies since 1978. In particular, Chinese transitional economies has led to fundamental changes in firms` activities under the socialist system. Nevertheless, Chinese firms have formed new industrial production organizations and spatial orders by sustaining personal networks based on existing traditional firm practice, which is called ``guanxi``. Therefore, the main purpose of this research is to identify the influence of personal networks, guanxi, on the business activities of Chinese firms by investigating the formation of guanxi mechanism. The main characteristics of guanxi represented in inter-firm relations are as follows. First, guanxi has played a role in facilitating inter-firm relations and business activities, because it has an inter-debt relations based on inter-reciprocal relations between firms. Second, Chinese firms has depended on posteriori guanxi rather than inherent guanxi by the internalization of personal networks through ``guanxi communicators``. Third, guanxi between firms and local government in extra-firm relations has been established to minimize risks from unstable legal regulations.

공익연계 마케팅(CRM) 메시지 제시 여부가 제품평가에 미치는 영향에 관한 연구: 광고소구유형과 제품유형의 조절효과를 중심으로

최자영 ( Ja Young Choi ),최윤식 ( Yun Sik Choi ) 한국소비자학회 2011 소비자학연구 Vol.22 No.3

공익연계 마케팅 활동함으로써 기업은 지속적인 이윤추구와 적극적인 사회적 책임활동을 할 수 있으며, 소비자들은 일부 금액의 기부를 통해 도덕적 만족을 얻을 수 있다. 하지만 공익연계 긍정적인 혜택에도 불구하고 학문적으로 공익연계 마케팅에 대한 연구들은 제한적으로 진행되어 왔다. 즉 기존의 연구들이 공익연계 마케팅 메시지가 기업의 이미지와 판매되는 제품에 미치는 긍정적인 영향력은 많이 검증되었으나 제품 유형과 광고소구유형에 따른 공익연계 마케팅 메시지의 영향력 차이의 검증은 부족하다. 예를 들면 특정 제품에서는 공익연계 마케팅이 효과적으로 나타난 반면, 그렇지 않는 경우도 있으며 어떻게 공익연계 마케팅 메시지를 제시하느냐에 따라서 그 효과는 다르게 나타나고 있다. 따라서 본 연구에서는 제품 유형 및 광고 소구 유형을 고려하여 공익연계마케팅의 메시지가 어떠한 상황에서 효과적인가를 밝혀보고자 한다. 따라서 본 연구에서는 제품유형(기능적/쾌락적), 광고소구유형(이성적/감성적), 공익연계 마케팅 메시지 여부가 제품평가에 미치는 영향력을 살펴보았다. 연구 1에서는 2×2×2 집단 간 실험설계(between-subjects factorial design)를 통해 공익연계 마케팅 메시지의 감성적 편익의 제공 여부를 검증하였다. 연구결과, 소비자는 공익연계 마케팅 메시지를 포함한 제품을 구매함으로써 감성적 편익을 얻으며, 이와 같은 감성적 편익은 기능적 제품보다는 쾌락적 제품에서, 이성적 광고소구보다는 감성적 광고소구에서 더 높았다. 연구 2에서는 연구 1과 동일한 방법으로 제품유형(기능적 vs. 쾌락적)과 광고소구유형(이성적 vs. 감성적)에 따라 공익연계 마케팅 메시지가 제품 태도와 구매의도에 미치는 영향력의 차이를 검증하였다. 연구결과, 공익연계 마케팅 메시지는 제품 태도와 구매의도에 긍정적인 영향력을 보였으며, 이와 같은 영향력은 기능적 제품보다는 쾌락적 제품에서 더 크게 나타났다. 또한 공익연계 마케팅 메시지와 광고소구유형 사이에서도 동일한 결과를 보였다. 즉, 공익연계 마케팅 메시지는 감성적 광고소구유형에 더 큰 영향력을 보였다. 본 연구에서는 이러한 결과를 바탕으로 실무적인 시사점과 향후의 연구 방향에 대하여 언급하였다. Many companies obtain benefits such as increasing sales profits and fulfilling social responsibility activities from Cause-Related Marketing(CRM) as a strategic marketing activity. Although this stream of research has contributed a great deal of insight for companies to plan a CRM activity, there is still a limited understanding of how to develop CRM campaigns or assess their impacts on both consumers and their organizations. Many previous studies have showed positive aspects of which a CRM message could influence consumers` beliefs and attitudes toward both products and companies, however, the effects of a CRM message on sales of product or brand images are shown to be inconsistent. Much extant study showed that the effectiveness of a CRM message could be affected by the nature of a product and context in which a CRM message is presented. In study 1, following hypotheses are tested through a 2(types of products: utilitarian vs. hedonic) × 2(types of advertising appeals: rational vs. emotional) × 2(CRM message present: ○ vs. ×) between-subject experiment. Hypothesis 1 explores the interaction effects of CRM message and types of products or types of advertising appeals on the extent of emotional benefits. The results show that a CRM message provides emotional benefits to consumers. Also, such benefits are higher when a CRM message is represented with hedonic products and emotional advertising appeals than when utilitarian products and rational advertising appeals does. In study 2, following hypotheses are tested through a 2(types of products: utilitarian vs. hedonic) × 2(types of advertising appeals: rational vs. emotional) × 2(CRM message present: ○ vs. ×) between-subject experiment. Hypothesis 2 explores the interaction effects between a CRM message and types of products on a product evaluation and purchase intentions. We assumed that there might be differences in the effect of a CRM message on an attitude toward a product and purchase intentions between utilitarian and hedonic products. Hypothesis 3 is about the interaction effects between a CRM message and types of advertising appeals. It tests the effect of a CRM message on consumers` attitude formation and purchase intention will be more positive in emotional advertising appeal than in rational advertising appeals due to the affect confirmation effects. The results show that a CRM message has a positive effect on consumers` attitude and purchase intention with both utilitarian and hedonic products. The positive effect of a CRM message is higher when the message is presented on hedonic products than utilitarian products. Also, there are differences in the relationships between types of products and types of advertising appeals in a consumers` attitude toward a product and purchase intention. An emotional advertising appeal with a hedonic product is shown to be the most effective on consumers` product evaluations and purchase intentions. Based on the findings, the theoretical and managerial implication are then discussed.

동양과 서양의 약초학 비교

최자영(Choi Ja-Young) 계명사학회 2006 계명사학 Vol.17 No.-

It has been argued that whereas traditional Eastern medicine gives much more emphasis on the circulation of the body as a whole. Western medicine makes analytic approaches on the parts of the body. In my opinion, however, the differences between them could not simply be defined, as there are various trends in each of them and which trends get the upper hand varies according to the period or social class being discussed. An example of this fact can be found in botanical medicine. The Eastern botanical medicine verifies the transition, from the stage in which the Theory of Yin-Yang (Dark-Bright. or Negative-Positive), or the Yin-Yang Five Elements, was not yet applied to, through the stage the theory began to appear in its rudiments, and to the later phase that it strengthens itself to be applied. The less the influences of Yin-Yang Five Elements Theory is. the more it is similar to the Greek botanical medicine as the origin of Western medical trends. This essay tries to show that the traditional medicines of the Chinese and the Greeks have common elements as well as differences, But, the differences do not lie in their viewpoints of the body, between regarding it as a whole and analytic approaches to it, respectively, as these two viewpoints can be found, in my opinion, in both China and Greece. For this purpose, will be discussed the Chinese traditional books of botanical medicine on the one hand, that is, Shennong's Classic of Materia Medica and Special Script of Famous Doctor which are scarecely influenced by the metaphysical theory of Yin-Yang, and the Harm-Cold Theory, which is in the early stage of being influenced by the Yin-Yang Theory, and the Medical Botany of Dioskurides of Greece, on the other hand, to compare the viewpoints for the effect of botanical plants between the East and the West. For almost all the kinds of medical plants, in Greece the effect of them refers to concrete organs of the body or detailed name of the disease, but in China it refers to more abstract and general concepts. for example, weakness (혹은 vacancy, 虛), vitality (혹은 Spirit, 氣), strengthening one's muscles and bones, lessening vitality, etc. Furthermore, in China the great concern is given to removing hunger. In Greece, however, references are more frequently made to blood angiostenosis (blocking) and constipation which are largely originated from a supply surplus of nutrition, as well as facilitating menstruation or sexual intercourse for reproduction and natural desire, nephrolith (kidney stone) and vermin-or beast-biting. The difference of knowledges in the effect of medical plants could not be explained without taking into consideration the living environment. China is a country of agriculture, thickly populated and labor intensive. usually not to have enough food materials for all to eat. On the contrary, Greece has much more meat and dairy products made from animals, which easily leads to excretion difficulties and blood angiostenosis as it is even today. The water rich in lime in Greece is a cause of nephrolith as an endemic disease, and the customary pastoral life in the open air makes anavoidable the frequent medical care for being bitten by insects, scorpions, snakes, etc. On the other hand, cinnamon, which is quite widely used as a medical plant in China to warm up the body and cheer up energy, is known only as a spice in Greece. The Greeks with animal foods are comparatively less in need for the medical stuff to warm the body up than the Orientals of vegetable diet.