• Korean Journal of Head & Neck Oncology
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• v.31 no.2
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• pp.86-90
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• 2015

Cystic lymph node metastasis of head and neck squamous cell carcinoma(HNSCC) which presumed to be mainly originated from oropharynx including Waldeyer's ring may present as a benign cystic mass on lateral neck such as branchial cleft cyst. Branchial cleft cyst is one of the most common lateral neck cystic mass which may result in regional infection or lymph adenopathy. Many of previously reported literatures showed the incidence of cystic lymph node metastasis from oropharynx including Waldeyer's ring. Preoperative imaging studies and fine needle aspiration cytology cannot provide the accurate results until excision of cystic mass for the diagnostic or therapeutic purpose. Recently, we experienced the rare case of cystic lymph node metastasis from ipsilateral tonsil, which mimicked infected 2nd branchial cleft cyst. Thus, we reported our experience with presentation of case and review of literatures.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.890-893
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• 2008

자율성 및 이동성 갖는 네트워크 구조의 하나인 MANET(Mobile Ad-Hoc Networks)은 각 node들은 그 특성에 따라서 clustering service을 한다. node의 전송과정 중 path access에 대하여 중요성 또한 강조되고 있다. 일반적인 무선 네트워크 상에서의 node들은 clustering을 하게 되는데 그 과정에서 발생되는 여러 가지 문제점을 가지고 전송이 이루어진다. 모든 node들이 송, 수신상의 전송 범위(Beam forming area)가지고 있으며, 이러한 각 node들의 전송범위 내에 전송이 이루어지는 전통적인 전송기술 mechanism을 찾는다. 이러한 전송상황에서의 송신하는 node와 수신된 node간에 발생되고 있는 중복성의 문제점으로 즉, 상호적용에 의한 네트워크 duplicate(overlapping)이 크게 우려가 되고 있다. 이러한 전송상의 전송 범위 중첩, node간의 packet 간섭현상, packet의 중복수신 및 broadcasting의 storming현상이 나타난다. 따라서 본 논문에서는 상황정보의 속성을 이용한 계층적 상호 head node들의 접근된 위치와 연계되는 전송속도, 보존하고 있는 head node들의 에너지 source value, doppler효과를 통한 head node의 이동방향 등 분석한다. 분석된 방법으로 전송상의 계층적 path가 구성된 경험적 path 속성을 통한 네트워크 connectivity 신뢰성을 극대화 할 뿐만 아니라 네트워크의 전송 범위 duplicate을 사전에 줄일 수 있고 전송망의 최적화를 유지할 수 있는 기법의 하나인 상황정보를 이용한 ad hoc network의 ODDMRP(Ontology Doppler effect-based Dynamic Multicast Routing Protocol) clustering 기법을 제안한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.4223-4249
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• 2015

A novel jamming detection technique to detect the presence of jamming in the downstream direction for cluster based wireless sensor networks is proposed in this paper. The proposed technique is deployed in base station and in cluster heads. The proposed technique is novel in two aspects: Firstly, whenever a cluster head receives a packet it verifies whether the source node is legitimate node or new node. Secondly if a source node is declared as new node in the first step, then this technique observes the behavior of the new node to find whether the new node is legitimate node or jammed node. In order to monitor the behavior of the existing node and new node, the second step uses two metrics namely packet delivery ratio (PDR) and received signal strength indicator (RSSI). The rationality of using PDR and RSSI is presented by performing statistical test. PDR and RSSI of every member in the cluster is measured and assessed by the cluster head. And finally the cluster head determines whether the members of the cluster are jammed or not. The CH can detect the presence of jamming in the cluster at member level. The base station can detect the presence of jamming in the wireless sensor network at CH level. The simulation result shows that the proposed technique performs extremely well and achieves jamming detection rate as high as 99.85%.

• Korean Journal of Head & Neck Oncology
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• v.29 no.2
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• pp.37-40
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• 2013

Background and Objectives : To assess the usefulness of computed tomography image before papillary thyroid cancer surgery, focus on confirmation of lateral cervical lymph node metastasis not detected by ultrasonography. Material and Methods : From January 2008 to May 2009, total 150 patients who had undergone thyroid surgery and been confirmed papillary thyroid cancer pathologically were enrolled. They had taken neck computed tomography following the ultrasonography. Results : Computed tomography had found suspicious metastatic lateral neck lesion in 13 patients. After the image study, lateral neck lymph node dissection had been included in their surgical plan. Of these, only 7 cases were confirmed pathologically lateral neck lymph node metastasis(positive predictive value=0.54). Taken as whole 150 patients, additionally 4.7% of patients confirmed lateral neck lymph node metastasis by preoperative computed tomography. Conclusion : If preoperative ultrasonography was performed precisely, additional benefits that could be achieved by computed tomography were not much.

• Korean Journal of Head & Neck Oncology
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• v.15 no.1
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• pp.9-17
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• 1999

Objectives: The records of 936 patients with previously untreated carcinoma of the head and neck were reviewed in order to define the incidence and topographical distribution of neck node metastasis on admission. Materials and Methods: The common regions of metastasis are presented for each of the 12th individual head and neck sites selected for study. Results and Conclusion: Knowledge of the preferred areas of spread and those that are almost never involved allows the design of more adequate radiation therapy plans to manage the individual tumors.

• Journal of IKEEE
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• v.20 no.4
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• pp.449-453
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• 2016

Failures would occur because of the hostile nature environment in Wireless Sensor Networks (WSNs) which is deployed randomly. Therefore, considering faults in WSNs is essential when we design WSN. This paper classified fault model in the sensor node. Especially, this paper proposed new error correcting code scheme and fault recovery algorithm in the CH(Cluster Head) node. For the range of the small size information (<16), the parity size of the proposed code scheme has the same parity length compared with the Hamming code, and it has a benefit to generate code word very simple way. This is very essential to maintain reliability in WSN with increase power efficiency.

• Korean Journal of Head & Neck Oncology
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• v.33 no.2
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• pp.81-84
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• 2017

Langerhans cell histiocytosis (LCH) is a heterogeneous disease, characterized by accumulation of dendritic cells with features similar to epidermal Langerhans cells. It is a rare entity that may involve various organ levels such as the skeletal, pulmonary, hematopoietic and lympho-vascular systems. The patient was a 1-year-old female presented with fever associated with otorrhea and palpable cervical lymph node for 4 days. Neck ultrasonography and Computed tomography imaging revealed multiple enlarged lymph nodes suggesting suspicious malignant morphology. Lymph node biopsy was performed under general anesthesia. Histological and immunophenotypic examination showed the lymph node to be consistent with LCH. The patient was given chemotherapy.

• Korean Journal of Head & Neck Oncology
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• v.32 no.2
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• pp.35-39
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• 2016

Castleman's disease (CD) is an uncommon lymphoproliferative disorder. The disease entity is classified into 2 clinical subtypes, unicentric and multicentric type. Prevalence of lymphoid malignancy in multicentric CD (MCD) is very low. In this case, we report a case of 77 years old woman who developed high fever and swelling in both side of her neck. Neck lymph node biopsy revealed plasma cell hyperplasia. Patient's symptom was subsided after treatment with Dexamethasone. Three months later, multiple lymph node enlargement was developed in abdomen and neck area again. Repeated neck lymph node biopsy confirmed diffuse large B cell lymphoma. The patient started chemotherapy.

• Korean Journal of Head & Neck Oncology
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• v.34 no.2
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• pp.17-21
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• 2018

Background/Objectives: Cancers of the abdominal or pelvic organ rarely metastasize to the cervical lymph nodes. Although it indicates distant metastasis, perceivable prolongation of survival or cure may be possible in selected cases. We sought to identify patients with cervical metastasis from cancers below the diaphragm and identify patients who may benefit from aggressive treatment. Materials & Methods: From 2009 to 2017, patients with pathologically confirmed metastatic cervical lymph nodes originating from below the diaphragm were included for analysis. Patient demographics, cancer characteristics, treatment course, and clinical outcomes were analyzed. Results: 208 patients were identified. Left supraclavicular node (Virchow's node) was the most frequently involved. Irrespective of treatment, survival for uterine cervical and ovarian cancers was significantly longer than that of other primaries. Patients with isolated cervical metastasis (oligometastasis) had significantly longer median survival compared to patients with concomitant bone, lung, brain, and mediastinal metastases. Conclusion: Although cervical metastasis from cancers of the abdominal and pelvic organ represent distant metastasis, patients with uterine cervix and ovary primary and oligometastatic lesions may benefit from aggressive treatment. Prudent patient selection and further investigation is warranted.

• Journal of IKEEE
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• v.22 no.3
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• pp.558-564
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• 2018

In distributed estimation where each node can collect only partial information on the parameter of interest without communication between nodes and quantize it before transmission to a fusion node which conducts estimation of the parameter, we consider a novel quantization technique employed at local nodes. It should be noted that the performance can be greatly improved if each node can transmit its measurement to one designated node (namely, head node) which can quantize its estimate using the total rate available in the system. For this case, the best strategy at the head node would be simply to partition the parameter space using the generalized Lloyd algorithm, producing the global codewords, one of which is closest to the estimate is transmitted to a fusion node. In this paper, we propose an iterative design algorithm that seeks to efficiently assign the codewords into each of quantization partitions at nodes so as to achieve the performance close to that of the system with the head node. We show through extensive experiments that the proposed algorithm offers a performance improvement in rate-distortion perspective as compared with previous novel techniques.