A correlation between comprehensive neck dissection and increased uptake around the sternoclavicular joint on post-operative 18F-FDG PET/CT

오소원,이도영,김보해,김광현,김유경,정영호,Oh, So Won,Lee, Doh Young,Kim, Bo Hae,Kim, Kwang Hyun,Kim, Yu Kyeong,Jung, Young Ho The Korean Society for Head and Neck Oncology 2018 대한두경부 종양학회지 Vol.34 No.1

Background/Objectives: This study aimed to evaluate the changes of uptake around the sternoclavicular joint (SCJ) according to 18F-FDG PET images in patients with head and neck cancer who underwent neck dissection. Materials & Methods: Retrospectively, the medical records of patients who received selective or comprehensive neck dissection were reviewed. Preoperative and 1-year postoperative 18F-FDG PET images, if available, were analyzed by nuclear medicine physicians in both qualitative and quantitative manners. Correlation between the changes of uptake around SCJ and perioperative data were statistically analyzed. Results: Thirty-seven patients satisfying the inclusion criteria were enrolled. Seven patients with increased uptake around SCJ on 1-year postoperative 18F-FDG PET showed a correlation with radical or comprehensive neck dissection, accessory nerve sacrifice, and high postoperative SUVmax. When 20 patients with increased uptake around SCJ according to quantitative measurement were compared with other patients without increased uptake, no parameter was significantly different, except postoperative SUVmax. Bivariate logistic regression analysis revealed that the clinical symptom (shoulder or sternal pain) was significantly correlated with the extent of neck dissection (OR 0.227, CI 0.053-0.966, p=0.045) and spinal accessory nerve sacrifice (OR 13.500, CI 1.189-153.331, p=0.036). Conclusions: Increased uptake around SCJ on 1-year postoperative 18 F-FDG PET was correlated with either the radical or comprehensive procedure, as well as with accessory nerve sacrifice. This suggests that subjective analysis of 18F-FDG PET can be used to detect subclinical shoulder instability.

Prostate-Specific Membrane Antigen PET Imaging in Prostate Cancer: Opportunities and Challenges

오소원,천기정 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.5

The aim of this systematic review was to describe the characteristics of prostate-specific membrane antigen (PSMA)-targeting PET and their clinical applications in prostate cancer patients. There have been major strides in the design, synthesis of PSMA-targeting PET tracers over the past several years. PSMA-targeting PET tracers can be categorized, according to positron emitters and targeting strategies for the PSMA. The majority of PSMA PET studies has been focused on patients with biochemical recurrence, but additional values of PSMA PET have also been investigated for use in primary staging, treatment planning, response evaluation, and PSMA radioligand therapy. PSMA PET is expected to bring improvements in the management of patients, but the impact of improved diagnosis by PSMA on overall survival remains unanswered. Many challenges still await PSMA PET to expedite the use in the clinical practice. At this early stage, prospective multicenter trials are needed to validate the effectiveness and usefulness of PSMA PET.

Current Status of PSMA-Targeted Radioligand Therapy in the Era of Radiopharmaceutical Therapy Acquiring Marketing Authorization

오소원,천기정,서민석 대한핵의학회 2022 핵의학 분자영상 Vol.56 No.6

Prostate-specific membrane antigen (PSMA) is highly expressed in PCa, which gradually increases in high-grade tumors,metastatic tumors, and tumors nonresponsive to androgen deprivation therapy. PSMA has been a topic of interest during thepast decade for both diagnostic and therapeutic targets. Radioligand therapy (RLT) utilizes the delivery of radioactive nuclidesto tumors and tumor-associated targets, and it has shown better efficacy with minimal toxicity compared to other systemiccancer therapies. Nuclear medicine has faced a new turning point claiming theranosis as the core of academic identity, sincenew RLTs have been introduced to clinics through the official new drug development processes for approval from the Foodand Drug Administration (FDA) or European Medical Agency. Recently, PSMA targeting RLT was approved by the USFDA in March 2022. This review introduces PSMA RLT focusing on ongoing clinical trials to enhance our understandingof nuclear medicine theranosis and strive for the development of new radiopharmaceuticals.

방사성요오드 치료저항성 갑상선암에서 방사성요오드 병용치료의 새로운 전략

오소원,팽진철,정준기 대한갑상선학회 2015 International Journal of Thyroidology Vol.8 No.1

The prognosis of differentiated thyroid cancer (DTC) is excellent, which is mainly due to the high therapeutic efficacy of radioactive iodine (RAI) therapy as well as indolent nature of thyroid cancer itself. Although most patients with DTC are well treated with RAI therapy, a certain number of patients have been suffered from refractoriness to RAI therapy. To overcome refractoriness, many alternative treatments have been investigated, and they could be classified based on the mechanisms of action; redifferentiation drug and molecular targeted drug. Not only redifferentiated drugs but also molecular targeted drugs could induce differentiation of thyroid cancer cells. Consequently, alternative treatments allowing tumor cells of RAI avidity followed by RAI therapy could utilize a synergistic effect of both therapies. Combined RAI therapy is expected to improve therapeutic effects and prognoses of RAI refractory thyroid cancers.

에너지 수확 모바일 센서 망을 위한 유체 흐름 및 군집 분산 기반 토폴로지 변환 알고리즘

소원호(Wonho So) 대한전자공학회 2013 전자공학회논문지 Vol.50 No.12

에너지 수확 모바일 센서 망에서 센서 노드간의 듀티-사이클 동기화는 매우 중요한 의미를 갖는다. 제한된 에너지를 효율적으로 사용하여 협력해야 하기 때문에 각 노드의 듀티-사이클이 서로 유사하게 동작되어야 한다. 이때 망을 구성하는 노드 분포는 노드간의 연결뿐만 아니라 동기화에 의한 노드의 활동 시간, 그리고 망의 수명에 영향을 준다. 본 논문에서는 자기-동기화 듀티-사이클 기법을 적용한 에너지 수확 모바일 센서 망에서 망의 토폴로지를 변화시킨다. 단순 랜덤 토폴로지 망보다는 망이 담당하는 영역과 노드 밀집도에 따라서 노드의 분포를 균일하게 유지하는 알고리즘을 제시한다. 제시된 토폴로지 변환 알고리즘을 위하여 유체 흐름과 군집 분산 모델을 적용하고 에이전트 기반 모델링을 이용하여 성능분석을 시행한다. 또한 제안된 알고리즘을 자기-동기화 듀티-사이클 기반 모바일 센서 망에 적용하여 노드 간 동기화 특성이 강화되고 에너지 소비 편차의 감소를 확인한다. The duty-cycle synchronization among mobile sensor nodes with energy-harvesting is very important. The nodes should keep their duty-cycle same to others as much as possible because they have to cooperate each other and to consume energy efficiently. The distribution of node position in network affects not only node connectivity but also the active time of synchronized nodes, and it relates to network life-time finally. In this paper, we introduce a network topology change algorithm (TCA) for energy-harvesting mobile sensor networks based on self-synchronized duty-cycling. The algorithm tries to change a network topology into a balanced topology where the mobile sensor nodes are unified according to the density of the number of nodes. For TCA, both fluid flow algorithm and flock dispersion algorithm are proposed and they are evaluated through the simulation in agent based modeling language. TCA is applied to the energy-harvesting mobile sensor networks to improve the synchronization of duty-cycle and to reduce the variation of energy consumption among nodes.

Hybrid Scaling Based Dynamic Time Warping for Detection of Low-rate TCP Attacks

소원호,유경민,김영천,So, Won-Ho,Yoo, Kyoung-Min,Kim, Young-Chon The Korea Institute of Information and Commucation 2008 韓國通信學會論文誌 Vol.33 No.7B

In this paper, a Hybrid Scaling based DTW (HS-DTW) mechanism is proposed for detection of periodic shrew TCP attacks. A low-rate TCP attack which is a type of shrew DoS (Denial of Service) attacks, was reported recently, but it is difficult to detect the attack using previous flooding DoS detection mechanisms. A pattern matching method with DTW (Dynamic Time Warping) as a type of defense mechanisms was shown to be reasonable method of detecting and defending against a periodic low-rate TCP attack in an input traffic link. This method, however, has the problem that a legitimate link may be misidentified as an attack link, if the threshold of the DTW value is not reasonable. In order to effectively discriminate between attack traffic and legitimate traffic, the difference between their DTW values should be large as possible. To increase the difference, we analyze a critical problem with a previous algorithm and introduce a scaling method that increases the difference between DTW values. Four kinds of scaling methods are considered and the standard deviation of the sampling data is adopted. We can select an appropriate scaling scheme according to the standard deviation of an input signal. This is why the HS-DTW increases the difference between DTW values of legitimate and attack traffic. The result is that the determination of the threshold value for discrimination is easier and the probability of mistaking legitimate traffic for an attack is dramatically reduced.

대역 액세스 망을 연결하는 파장 공유 노드 기반 WDM 메트로 링의 MAC 프로토콜 성능 평가

소원호 대한전자공학회 2006 電子工學會論文誌-TC (Telecommunications) Vol.43 No.1

In this paper, a node architecture of WDM metro network for connecting broadband access networks to converge wire/wireless networks. In consideration of the proposed node architecture and network requirements we proposed and evaluated medium access control protocols. We review WDM related technologies of sub-carrier multiplexing and optical components in order to resolve the bottleneck between optical backbone networks and access networks, and a access node architecture sharing common wavelength is introduced. Source-stripping (SS) MAC protocol is evaluated under the proposed functional node architecture. DS+IS (Destination-Stripping and Source-Stripping) and DS+IS (Destination-Stripping and Intermediate-Stripping) MAC protocols are described to increase the slot-reuse factor which is low on SS MAC protocol. The key function of new MAC protocols regards the optical switch module of proposed node architecture and helps intermediate or source access nodes for dropping slots to destinations of different wavelength group. Thus, slot-reuse factor increases as the MAC protocols reduce the unnecessary ring-rotation of transferred slots. We use a numerical analysis to expect bandwidth efficiency and maximum throughput by slot-reuse factor. Throughput network simulation, the verification of throughput, queuing delay, and transmission fairness are compared among MAC protocols. 본 논문에서는 유무선 통합을 위한 광대역 액세스 망의 연결을 지원하는 파장 분할 다중화 (Wavelength Division Multiplexing; WDM) 메트로(metro) 망을 위한 노드 구조를 제안한다. 또한 노드 구조의 기능과 망 요구 사항을 고려한 매체 접근 제어 (Medium Access Control; MAC) 프로토콜을 제안하고 성능을 비교평가한다. 광통신 백본 망과 액세스 망사이의 병목현상을 해결하기 위하여 WDM, 서브 캐리어 다중화 기술, 광소자 기술 등을 살펴보고 고비용 자원에 해당하는 파장 채널의 공유를 위한 액세스 노드 구조를 제안한다. 또한 제안된 기능 모델을 이용하여 기존 SS (Source-Stripping) MAC 프로토콜을 분석하고 슬롯 재사용성을 높이기 위한 DS+SS (Destination-Stripping and Source-Stripping)와 DS+IS (Destination-Stripping and Intermediate-Stripping) MAC 프로토콜을 제시한다. 제안된 프로토콜은 다른 파장 그룹의 목적지 노드로 슬롯이 전송되는 경우에 목적지에 따라서 슬롯의 제거를 중간 액세스 노드나 근원지 노드에서 수행한다. 따라서 전송된 슬롯의 불필요한 망 순환을 줄임으로써 슬롯 재사용성이 증가한다. 슬롯 재사용성에 의한 대역 효율성과 노드의 최대 처리율을 예측하기 위하여 수치적 분석을 수행하며 네트워크 시뮬레이션을 통하여 처리율 검증과 전송 지연, 전송 공정성 등의 다양한 성능 파라미터를 기존 프로토콜과 비교 평가한다.

Hybrid Scaling Based Dynamic Time Warping for Detection of Low-rate TCP Attacks

소원호,김영천,유경민 한국통신학회 2008 韓國通信學會論文誌 Vol.34 No.10

In this paper, a Hybrid Scaling based DTW (HS-DTW) mechanism is proposed for detection of periodic shrew TCP attacks. A low-rate TCP attack which is a type of shrew DoS (Denial of Service) attacks, was reported recently, but it is difficult to detect the attack using previous flooding DoS detection mechanisms. A pattern matching method with DTW (Dynamic Time Warping) as a type of defense mechanisms was shown to be reasonable method of detecting and defending against a periodic low-rate TCP attack in an input traffic link. This method, however, has the problem that a legitimate link may be misidentified as an attack link, if the threshold of the DTW value is not reasonable. In order to effectively discriminate between attack traffic and legitimate traffic, the difference between their DTW values should be large as possible. To increase the difference, we analyze a critical problem with a previous algorithm and introduce a scaling method that increases the difference between DTW values. Four kinds of scaling methods are considered and the standard deviation of the sampling data is adopted. We can select an appropriate scaling scheme according to the standard deviation of an input signal. This is why the HS-DTW increases the difference between DTW values of legitimate and attack traffic. The result is that the determination of the threshold value for discrimination is easier and the probability of mistaking legitimate traffic for an attack is dramatically reduced.

Impact of the Members' Mood on Information Sharing during Groop Discussion

소원현 한국시민윤리학회 2009 한국시민윤리학회보 Vol.22 No.2

The effects of moods on group decision-making task were explored. College students were assigned to one of 2 experimental mood conditions (i.e., positive and negative). It was predicted that participants in positive moods shared more information than those in negative moods. The results suggested that individuals in positive mood states share more of unshared information than negative moods in group decision-making task. It was also found that, when group members were in a positive mood, they considered information more inclusively. In this study, story-writing task was modified in order to manipulate the participant mood states. Additionally, “teaching award task” was developed successfully in order to test the effects of moods on sharing unshared information.

WDM 메트로 링에서 공정한 전송을 위한 확률기반 MAC 프로토콜에 대한 성능 평가

소원호,김영천,So Won-Ho,Kim Young-Chon 한국통신학회 2006 韓國通信學會論文誌 Vol.31 No.4B

본 논문에서는 FT-TR(Fixed Transmitter-Tunable Receiver) 형 액세스 노드를 사용하여 광대역 액세스 망을 연결하는 파장 분할 다중화 (Wavelength Division Multiplexing; WDM)기반의 메트로(metro) 링에서 공정한 전송을 위한 MAC 프로토콜을 제안한다. 기본적인 채널 액세스 방식은 CSMA/CA(Carrier Sense Multiple Access with Collision Avoidance)이며 메트로 링을 순환한 전송된 슬롯은 SS(Source-Stripping) 방식으로 패킷이 제거되어 빈 슬롯이 된다. 빈 슬롯은 바로 패킷 전송에 이용되거나 다음 액세스 노드에 그대로 전송될 수 있는데, 전자는 망의 처리율은 향상되나 공정성에 문제가 발생되며 후자는 공정성은 향상되나 처리율이 낮은 단점을 갖는다. 따라서 제안된 MAC 프로토콜은 전자와 후자의 장점을 이용한다 제안된 프로토콜은 p-Persistent MAC 프로토콜로서 파장 채널을 공유하는 액세스 노드는 하향 액세스 노드에게도 빈 슬롯을 이용하도록 확률적으로 전송 기회를 주고, 상향 액세스 노드의 무조건적인 빈 슬롯 사용을 확률적으로 억제하는 방식이다. 수치적 분석을 통하여 제안된 프로토콜에 대한 대역 효율성과 최대 노드 처리율을 분석하고 시뮬레이션을 통하여 확률에 따른 노드 처리율, 전송 공정성, 전송 지연 등의 다양한 결과를 분석한다. 또한 FT-TR 형 액세스 노드인 FT-FRn (Fixed Transmitter-nFixed Receivers)과 FT-TR 구조로 메트로 망을 구성하여 제안된 MAC 프로토콜을 비교 평가한다. In this paper, we consider a WDM based metro ring connecting broadband access networks by using FT-TR (Fixed Transmitter-Tunable Receiver) type access nodes and a new MAC protocol for fair transmission is proposed. The basic channel access scheme is CSMA/CA(Carrier Sense Multiple Access with Collision Avoidance) and the transferred optical slot is changed to be empty slot by SS(Source-Stripping) which drops a packet from ring-rotated slot. This empty slot can be either used to send head-of-line packet in buffer or transmitted to next access node. In former cases, there is the improvement of network throughput, but latter case leads unfairness problem of transmission. Thus the proposed MAC protocol exploits the advantages form tow cases. It gives downstream access nodes chance to use empty slots and limits the unconditional usage of empty slots at upstream access nodes with probability as called p-Persistent MAC protocol. We use a numerical analysis to evaluate bandwidth efficiency and maximum node throughput and compares simulation results in terms of node throughput, fairness factor, transfer delay depending on probability. Under two different FT-TR type architectures for metro ring network the proposed MAC protocol is evaluated and compared.