심층 합성곱 신경망을 이용한 레이더 신호 탐지 성능 분석

이의진,심재혁,김은희 한국방송∙미디어공학회 2023 방송공학회논문지 Vol.28 No.4

Recently, studies to utilize artificial neural networks in radar detection have been actively conducted. In this paper, we compare the performances of SOTA (State Of The Art) neural networks when applying to radar detection. The detection networks consist of two paths to detect the range and Doppler frequency. Among the networks used, HRNet shows the best performance for the range detection, and EfficientNet shows the best performance for Doppler frequency prediction. Although the detection probability is slightly lower than the conventional radar signal processing result, it is somewhat insensitive to the detection threshold, and the false alarm rate is quite low. Therefore, it is expected that the SOTA networks can be well utilized in radar detection.

Enhanced performance on the polymer light emitting diodes by using alcohol/water soluble discotic liquid crystals

이의진,허수원,송호준,문두경 한국공업화학회 2014 한국공업화학회 연구논문 초록집 Vol.2014 No.1

Polymer light emitting diodes (PLEDs) are an attractive emerging technology with potential advantageous features, such as mechanical flexibility and solution processability. However, the performance and cost of solution-processed PLEDs still need to be improved for commercialization. To enhance the performance of polymer light emitting diodes the alcohol/water soluble discotic liquid crystals(DLCs) were introduced as an electron transport layer (ETL). DLCs have high charge mobility through their one-dimensional columnar axis. PLED devices were successfully fabricated through solution process. In the PLED devices with DLC interlayers, electron mobility of devices were improved and device performances were enhanced.

유명인 안경사의 필요성 조사

이의진,정성훈,강인수,이도현,오현진,최가을 대한시과학회 2019 대한시과학회지 학술대회 Vol.2019 No.07

2P-491 Study on Molecular Conformation and Arrangement of CPEs as Hole Transporting Layer of Organic Optoelectronic Devices

이의진,한용운,문두경,강진규,김대환 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.1

In this study, three synthesized conjugated polymer electrolytes (CPEs) with different conjugation lengths were introduced as the hole transporting layer (HTL) of organic solar cells (OSCs) and polymer light emitting diodes (PLEDs). In order to control the dipole moment of CPEs, three different spacer units were choiced. The synthesized n-type CPEs were modified to p-type CPEs by facile oxidation process. To identify the effect on electrode work function tunability by changing molecular conformation and arrangement, we simulated density function theory (DFT) calculations of these molecules and performed ultraviolet photoelectron spectroscopy (UPS) analysis for films of indium-tinoxide (ITO)/CPEs. Additionally, we fabricated OSCs and PLEDs by using the CPEs as the HTL. As a result, the stability and performance were enhanced in the optimized devices with PFtT-D CPE HTL compared with PEDOT:PSS HTL-based devices.

대통 신수의 일행삼매에 관한 고찰

이의진 동아시아불교문화학회 2020 동아시아불교문화 Vol.0 No.42

This paper is about the study on the singleminded-practice samādhi (一行三昧 A samādhi of perfect unity of body and mind in all activities) of Shenxiu (神秀 606–706) who inherited the Dongshan Famen (東山法門 East Mountain Teachings). The Dongshan Famen emphasized "singleminded-practice samādhi" as the key thought of the teaching based on the Saptaśatikāprajñāpāramitā Sutra. Shenxiu didn't use the terminology, “singleminded-practice samādhi”. However, in the Shenxiu works such as Guanxin-lun (觀心論) and Dashengwusheng-fangbianmen (大乘無生方便門) on the canonical source Lengjia shizi ji (楞伽師資記), we can confirm the uniformity; absolute equality with neither discrimination nor antagonism (一相 true thusness; the one mind in all things). Fundamentally mind-observing (觀心) is to realize the two aspects of our mind: defiled mind (染心) and immaculate mind (淨心). Nothing exists outside of the mind. Hence contemplation of the mind is to look into the nature of all things. Shenxiu emphasized that all Buddha-works (佛事) such as three categories of pure precepts (三聚淨戒), six pāramitās (六波羅蜜), building temples, worshipping, lanterning lighting, purification (齋戒) and etc. should be done on the basis of single-minded practice (觀心一法). The distinct characteristic of Shenxiu is ‘right mindfulness (正念)’. Right Buddha chanting (正念佛) is the core subject of Diamond Sutra i.e. absence of characteristics of all things (無相). Chanting without perceptual attributes or form (相) is the very characteristics of Buddha. Fundamentally both Southern and Northern School of Chan are based on the same thought: The true mind that aspires for true-suchness, or the straight forward mind (直心). The terms mentioned in the Northern School of Chan such terms as “singleminded-practice samādhi”, thoughtlessness (無念) and prajñā-samādhi (般若三昧) are coincided with that of “the singleminded samādhi” in the Saptaśatikāprajñāpāramitā Sutra. Basically the standpoint of both Southern and Northern School of Chan regarding ‘Ultimate Reality’ is all the same. However, Shenxiu fundamentally put first the expediency of the “singleminded samādhi”, mind-observing (觀心) and chanting without form (無相念佛) and expanded further chanting Buddha as practice method. Accordingly he accepted both the wisdom of the “singleminded-practice samādhi” of Saptaśatikāprajñāpāramitā Sutra and the Buddha-recollection samādhi. 이 글은 동산법문을 계승한 신수의 일행삼매에 대한 고찰이다. 동산법문은 『문수설반야경』에 의거한 일행삼매를 중요한 사상으로 부각시켰다. 신수는 일행삼매라는 단어를 직접적으로 사용하지 않지만 『능가사자기』의 전거를 바탕으로 신수의 저작이라 불리는 『관심론』과 『대승무생방편문』에서 무상법계의 일상(一相)을 확인할 수 있다. 신수의 일행은 관심(觀心)이며 무상염불(無相念佛)이다. 관심은 본래의 마음을 관(觀)하는 것으로 마음에 정심(淨心)과 염심(染心)이 일어남을 아는 것이다. 그는 삼취정계와 육바라밀, 가람과 불상 조성, 소향예배, 연등과 꽃 공양, 재계 등 불사(佛事)의 모든 행은 관심일법의 바탕에서 실천해야 한다고 말한다. 신수 염불의 특색은 ‘정념(正念)’이다. 정념은 바른 계행이고 여래가 되는 것이다. 이 정염불(正念佛)은 『금강경』의 핵심주제인 무상과 연결된다. 상(相)이 없는 염불이 그대로 부처이며 허망한 상을 여읜 무상을 통해 여래의 성품을 볼 수 있는 것이다. 남북 양종 모두 일행삼매에 의의를 두고 사상을 펼친다. 남종에서 말하는 직심(直心)의 일행삼매, 무념(無念)과 반야삼매 등은 『문수설반야경』의 일행삼매와 부합한다. 남북종 모두 마음의 실상을 바라보는 궁극의 입장에서는 동일하다. 그러나 신수는 일행삼매의 방편인 관심과 무상염불을 근본에 두고 구칭염불을 실천행으로 확대하여 일상에서 일어나는 자기 마음의 단속을 중시한다. 앉고 서는 모든 행위에서 일상(一相)의 일행을 실천하여 밖으로 향해 있는 마음을 안으로 반조하는 관심과 무상의 일행을 통해 마음의 불토(佛土)를 이룰 수 있다는 것이다. 따라서 『문수설반야경』의 일행삼매에 나타난 반야와 염불삼매를 모두 수용한 것으로 보이며 일행삼매의 사상과 밀접한 관계에 있다고 할 수 있다.

Improvement in stability and performance of polymer solar cells by modifying PEDOT:PSS hole extraction layer with conjugated polymer electrolyte

이의진,정승은,최민희,문두경 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.1

In this study, we fabricated normal structured polymer solar cells (PSCs) by introducing a hole extraction layer (HEL) that consisted of poly (3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) and conjugated polymer electrolyte (CPE). The CPE can act as a conjugate base against the PSS and screen the coulombic attraction between PEDOT chains and PSS chains. By blending PEDOT:PSS and CPE, the acidity of the HEL solution and stability of the surface morphology and potential of the HEL film in air were reduced. The changes of surface properties were analyzed by using atomic force microscopy (AFM) and electrostatic force microscopy (EFM). As a result, the half-life of the PSC fabricated with blended HEL was five times better at ambient condition (25 °C and 40% humidity) without encapsulation as compared to the pristine PEDOT:PSS-based device.

Enhanced Performance in Organic Optoelectronic Devices Using Conjugated Polyelectrolytes as Hole Transporting Layer

이의진,최민희,한용운,문두경 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.1

The modification of the interface between the electrodes and the organic active layer of organic optoelectronic devices, such as polymer light emitting diodes (OLEDs) and polymer solar cells (PSCs), is regarded as important issue In order to improve performance. A hole transporting layer (HTL) play a role to reduce energy barrier between the anode and the organic active layer to improve transportation of holes. In this study, we synthesized three conjugated polyelectrolytes (CPEs) with different conjugation length to control dipole moment. The PLEDs and PSCs were fabricated by using CPEs as HTL. The device performances with different dipole moment of CPEs were enhanced, compared with PEDOT: PSS based device.

Low-temperature solution processed perovskite solar cells

이의진,김두헌,허수원,문두경 한국공업화학회 2014 한국공업화학회 연구논문 초록집 Vol.2014 No.1

Organic-inorganic hybrid perovskite solar cells that combine a mesoporous scaffold, an organometal trihalide perovskite light absorber and an organic hole transporter have exhibited high efficiencies over 12%. However, they require high processing temperatures of up to 500°C to sinter the metal-oxide paste to form the mesoporous scaffold. To fabricate low-temperature processable perovskite solar cells, we introduced sol-gel processed metal oxide scaffold. The metal oxide scaffold showed high electron mobility and enhanced surface morphology than TiO₂ scaffold. We successfully fabricated low-temperature processed perovskite solar cell devices on the sol-gel processed metal oxide scaffold. Photovoltaic performances were characterized and showed efficient power conversion efficiency.

Relationship of Subjective and Objective Sleep Quality with Caregiver Burden in Patients with Alzheimer’s Disease

이의진,김성재,이선희,장재원,주진형,이정희 대한수면학회 2021 sleep medicine research Vol.12 No.1

Background and Objective Sleep disturbance in patients with Alzheimer’s disease (AD) could increase institutionalization due to caregiver burden. The objective of this study was to examine the relationship of subjective and objective sleep quality with caregiver burden in AD patients with insomnia symptoms. Methods AD patients of mild to moderate degree were recruited. They were assessed with the Pittsburgh Sleep Quality Index (PSQI), Korean version of the Epworth Sleepiness Scale, and Mini-Mental Status Examination in the Korean version of Consortium to Establish a Registry for Alzheimer’s Disease Assessment Packet. Caregiver burden was evaluated with Korean version of the Neuropsychiatric Inventory Questionnaire (KNPI-Q) and Korean version of the Zarit Burden Interview (ZBI-K). Actigraphy recording (Actiwatch 2; Philips Respironics) was conducted for five days at home. Thirty-four patients (age 78.44 ± 6.14, M:F = 9:25) were analyzed. These patients were divided into two groups by the median of KNPI-Q for caregiver distress [KNPI-Q(d)] and ZBI-K scores. Sleep parameters were compared between the two groups. Results Among seven components of PSQI, sleep latency was correlated with KNPI-Q(d) score. The patients with higher KNPI-Q(d) scores had lower sleep efficiency (SE) (p = 0.002), greater wake after sleep onset (p = 0.037), and higher fragmentation index (p = 0.040) than those with lower KNPI-Q(d) scores. Those with higher ZBI-K scores had lower SE (p = 0.026) than those with lower ZBI-K scores. Stepwise multiple regression revealed that SE predicted 16% of KNPI-Q(d) scores (p = 0.012). Conclusions Difficulty in sleep initiation according to subjective reports was associated with caregiver burden in our AD patients. In objective sleep quality, a significant difference in difficulty of sleep maintenance was found between higher and lower caregiver burden groups. This suggests that sleep maintenance is essential for reducing caregiver burden.

북한이탈주민의 초점집단면접을 중심으로 한 북한의 부모-자녀관 연구

이의진,박솔지 건국대학교 인문학연구원 2019 통일인문학 Vol.79 No.-

이 글은 북한이탈주민을 대상으로 한 초점집단면접(Focus Group Interview)을 통해 북한의 부모-자녀관을 포착하는 데에 목적을 둔 연구이다. 초점집단면접은 면접 참가자들이 해당 주제에 대한 의견을 함께 나누는 과정 속에서 관련 정보가 보다 객관화될 수 있다는 장점을 갖는다. 이에 따라 이 연구에서는 보다 일반적인 북한 주민의 가치관을 포착하기 위한 연구 방법으로서 초점집단면접을 채택하였다. 가치관은 사람들의 일상적 사회관계망에서 생성되는 가치지향성이기 때문에 부모-자녀 관계에서 형성된 가치관은 북이라는 국가가 지향하는 체제 이데올로기와 괴리가 있을 수밖에 없다. 한편 북은 해방 후 사회주의 건설을 목표로 ‘가정혁명화’를 내세우며 전통적 가족관계를 와해하려 하였고, 1990년에 제정된 가족법에 ‘사회주의 대가정론’을 규정하여 그동안 국가가 지었던 책임을 가정으로 전가하였다. 북한 사회의 변화과정은 북한식 사회주의와 수령 중심 국가 가부장제라는 독특한 사회구조를 만들어왔고, 이는 가정 내의 전통적 가부장제를 더욱 강화하게 하는 결과를 낳았다. 북의 부모-자녀관은 연령 및 성별보다 지역 및 계층별 차이가 컸으며, 일반적으로 여전히 전통적 훈육방식과 효 관념을 상호수용하고 있는 것이 확인되었다. 고난의 행군 이후 경제 상황의 변화로 가정 내 여성의 위상이 높아졌지만, 부모-자녀 사이의 가치관 변화는 두드러지지 않은 것이다. 또한 부모에 대한 효성이 가정 내에서는 더욱 확고하게 다져지는 반면, 국가를 향한 충심은 이전보다 약화되어 국가 체제 이데올로기와 현실 세계의 가치관은 더 큰 간극이 생성되고 있었다. 북한 사회는 계속적으로 변화하고 있고, 이에 따라 앞으로 북한 주민의 가치관도 변해갈 것이다. 그럼에도 불구하고 향후 남과 북이 서로 교류와 만남을 진행하게 될 경우, 이와 같은 북한 주민의 가치관은 남쪽 주민과의 가치충돌을 빚을 것으로 예상된다. 따라서 민주적인 가족, 탈가부장적이면서 평등한 가족에 대한 인식을 만들어가는 관점에서 남과 북 사이에 빚어질 수 있는 가치충돌에 대한 대안적 방법을 모색할 필요가 있다. The present research examines parent-child relationships in North Korea based on the Focus Group Interview(FGI) of North Korean defectors. The FGI method has the advantage of producing more objective information during the participants’ engagement in the discussions on a given subject. Therefore, the FGI method is used as a way to capture the value systems of the North Korean people on a general level. As value systems are formulated in social relations, the North Korean people’s views on parent-child relationships must be distinguished from official ideology. At first, the socialist nation building dictated the transformation to a “revolutionary family” which stood at odds with traditional family relations. The Family Law proclaimed in 1990 redefined the role of the socialist family to assume the responsibilities that the state had previously fulfilled. This resulted in North Korean-style socialism and the suryong-centered state patriarchy, which further strengthened the weight of traditional patriarchy within the family. The FGI research found that class was more important than other factors such as age, gender, or religion in shaping North Korean views on family-child relationships. In general, North Koreans still tended to rely on traditional disciplinary practices and concept of filial piety. Although the Arduous March elevated women’s status in the family, this change did not significantly affect their values on parent-child relationships. The persistence of firm filial piety within the family did not translate to a corresponding sense of loyalty to the state. There seems to be an increasing gap between regime ideology and real world values. North Korean society continues to change, and the people’s values will change accordingly. Nonetheless, the process of future contacts between the people of South and North Korea will likely be conflict-ridden by the clash of sociocultural values. This can be mitigated by forming an alternative family culture based on democratic values which will reduce the impact of patriarchy in both Koreas.