• 가정∙방문간호학회지
• /
• 제17권2호
• /
• pp.144-155
• /
• 2010

Purpose: This study investigated the factors affecting the quality of life (QOL) of the primary caregivers of home health care patients. Method: The subjects were 110 primary caregivers of patients who were receiving home health care from two home health care centers affiliated with general hospitals in Seoul. Data collection was conducted using five questionnaires. Results: Positive relationships were evident between QOL and social support and perceived health status of the primary caregiver. Negative relationships were evident between QOL and burden and depression. Multiple linear regression analysis for QOL revealed that the most powerful influencing factor was social support. Social support, burden, and depression explained 34.3% of the variance. Conclusion: Burden, depression, and social support are related with QOL of primary caregivers of home health care patients. Nursing intervention strategies directed at this caregiver population are needed.

• Journal of Gastric Cancer
• /
• 제3권3호
• /
• pp.139-144
• /
• 2003

Purpose: Because of an improving gastric cancer detection program and treatment methods, we can expect improved survival of patients with gastric cancer. Given the longer survival times, the chance of an occurrence of multiple primary malignant tumors other than stomach is increased in the same patients. The purpose of this study is to analyze the clinical characteristrics and the survival of patients with gastric cancer and other malignancies. Materials and Methods: A retrospective study of 3669 patients with gastric cancer observed at our department between January 1994 to December 2002 was conducted. Associated tumors were diagnosed using the Warren and Gates criteria, and included tumors that were not considered to be a metastasis, invasion, or recurrence of the gastric cancer. Results: Of all 3669 patients, $2.07\%$ (n=76) had primary tumors other than gastric cancer, $63\%$ of which were synchronous (n=48) and $37\%$ metachronous (n=28). The mean age of the study group was 64.9 (65.5 in males, 61.8 in females), and the male-to-female ratio was 4.8 : 1. The most common cancer associated with gastric cancer was a hepatocellular carcinoma ($23.7\%$), followed by colorectal cancer ($17.1\%$), esophageal cancer ($10.5\%$), breast cancer ($6.6\%$). Of the 45 patients who had undergone a resection, 14 were in stage I, 12 in stage II, 13 in stage III, and 6 in stage IV. No statistically significant differences were found between the synchronous and the metachronous groups with regard to age, sex ratio, differentiation, and stage. The 5-year survival rates of the metachronous and the resected patients were significantly higher than those of the synchronous and the non resected patients, respectively. Conclusion: Due to increasing length of the follow-up period for patients with gastric cancer, another malignancy may develop in other organs. Therefore, physicians should pay attention to detect other cancers early in these patients, and a surgical resection is recommended as the treatment of choice in the management of multiple primary cancer associated with gastric cancer.

• Radiation Oncology Journal
• /
• 제20권3호
• /
• pp.199-205
• /
• 2002

목적 : 본 연구의 목적은 악성 성상세포종 및 교모세포종 환자들의 방사선 치료 시 가장 적절한 조사 영역을 알아 보고자 시행하였다. 대상 및 방법 : 1994년 1월부터 2000년 3월까지 악성 성상세포종 및 교모세포종으로 진단되어 수술 및 방사선 치료를 받은 후 MRI로 추적관찰이 시행된 환자 중 재발이 확인된 21 명을 대상으로 분석하였다. 원발 병소 바깥 경계에서부터 처음 재발이 확인된 병소까지의 거리를 측정하였다. 그 외에 종양의 크기, 부종의 정도, 수술 절제의 범위, 감마나이프를 이용한 정위방사선수술, 다발성 병변 등이 재발 양상에 미치는 영향에 대하여 분석을 하였다. 결과 : 총 21명 중 18명$(86\%)$이 2 cm 이내에서 재발을 하였다. 이들 중 1 cm 이내가 12명, $1\~2\;cm$ 사이의 재발이 6명이었다. 나머지 3명의 재발은 3 cm, 4 cm, 5 cm, 떨어져서 각각 재발을 하였다. 2 cm 이상 떨어져 재발한 3명은 모두 다발성 병변이 있는 환자였다. 종양의 크기, 부종의 범위, 수술 절제의 범위, 감마나이프 시행 유무에 따른 재발의 양상에 차이가 없었다. 다만 다발성 병변일 경우 더 멀리서 재발하는 경향을 보였다. 결론 : 악성 성상세포종 및 교모세포종에서 재발 양상은 원발 병소 준위의 2 cm 이내 재발이 주 재발 양상이었다. 방사선 조사영역의 넓이는 부종의 범위나, 병소의 크기, 감마 나이프 수술 등에 따라 더 넓힐 필요는 없는 것으로 판단된다. 그러나 다발성 병변의 경우에는 단일 병소보다 더 넓은 조사 범위가 필요할 것으로 생각된다.

• 인터넷정보학회논문지
• /
• 제3권5호
• /
• pp.31-39
• /
• 2002

인터넷의 초고속 성장과 멀티미디어 데이터의 급격한 증가로 고속의 전송 매체와 인터페이스 시스템이 요구되고 있다. 이러한 고속의 네트워크 대역폭을 지원하기 위한 대안으로 다중(Multiple) NIC가 개발되고 연구되어 왔다. 다중 NIC를 사용함으로써 기존 네트워크 환경의 큰 변화 없이 고속의 LAN 환경을 구축할 수 있으므로 고성능. 저비용의 효과를 얻을 수 있다. 그러나 대용량 다중 NIC에 SPOF(Singe Point Of Failure) 결함으로 시스템 중단이 생기면, 대용량의 멀티미디어 데이터를 서비스하는 시스템인 만큼 커다란 손실을 가져오게 된다. 따라서 본 논문에서는 결함으로 오는 손실을 방지하기 위해 결함 허용 기법을 사용하여 '결함 허용 다중 NIC'에 대해서 연구한다. 기존의 TMR, Primary-Standby 기법. Watchdog Timer 기법에서 발생되는 자원에 대한 가용성과 내구성의 비효율적인 부분을 고려하여, 동적으로 검출 주기를 변환하여 다운타임을 최소화 할 수 있는 효율적인 결함 허용 메커니즘을 설계하여 제안한다. 결과적으로 본 논문에서 제안한 결함 허용 기법은 결함이 발생하여 생기는 오버헤드 시간을 줄이고자, Fault Detection에서 소요되는 Timeout 시간을 감소시켜 시스템 전반적으로 다운타임을 최소화시킬 수 있다.

• 천문학회지
• /
• 제38권2호
• /
• pp.237-240
• /
• 2005

We present images of L1551 IRS5 at angular resolutions as high as ${\~}$30 mas, corresponding to a spatial resolution of ${\~}$5 AU, made at 7 mm with the VLA. Previously known to be a binary protostellar system, we show that L1551 IRS5 is likely a triple protostellar system. The primary and secondary components have a projected separation of ${\~}$46 AU, whereas the tertiary component has a projected separation of ${\~}$11 AU from the primary component. The circumstellar dust disks of the primary and secondary components have dimensions of ${\~}$15 AU, whereas that of the tertiary component has a dimension of ${\~}$10 AU. Their major axes are closely, but not perfectly, aligned with each other, as well as the major axis of the surrounding flattened, rotating, and contracting molecular condensation (pseudodisk). Furthermore, the orbital motion of the primary and secondary components is in the same direction as the rotational motion of this pseudodisk. We suggest that all three protostellar components formed as a result of the fragmentation of the central region of the molecular pseudo disk. The primary and secondary components, but apparently not the tertiary component, each exhibits a bipolar ionized jet that is centered on and which emergers perpendicular to its associated dust disk. Neither jets are resolved along their base, implying that they are driven within a radial distance of ${\~}$2.5 AU from their central protostars. Finally, we show evidence for what may be dusty matter streams feeding the two main protostellar components.

• Journal of Korean Neurosurgical Society
• /
• 제30권9호
• /
• pp.1108-1114
• /
• 2001

Objective : Prognostic factors of metastatic brain tumors have been widely reported and their operative indications also have been extended gradually even to the poor grade patients. Authors intended to analyze the causative factors for the clinical outcome of metastatic brain tumors, especially with relevant to the poor prognosis by one year follow-up evaluation. Patients and Methods : The authors retrospectively studied the clinical characteristics of 46 cases(35 patients) with metastatic brain tumors among 466 cases(437 patients) which were operated on due to the brain tumor, during the period between January 1994 to June 1999. Statistical analysis was performed by using SPSS 8.0$^{(R)}$. A p-value of less than 0.05 was considered clinically significant. Result : Among the variable clinical factors in patients with metastatic brain tumors, Karnofsky Performance Scale (KPS) score of less than 70(16 patients), uncontrolled primary tumor(8 patients), and surgical resection without further adjuvant therapy(9 patients) showed statistically significant poor prognosis ; p value of 0.002, 0.032, and 0.001, respectively. Other tested variables, such as old age(greater than 65 years ; 10 patients), gender(male ; 20 patients), type of primary cancer(primary undefined ; 6 patients, lung cancer ; 15 patients), location(infratentorial ; 9 patients, sellar ; 5 patients), number of lesion(multiple ; 12 patients), and number of operation(multiple craniotomy ; 7 patients) were not related to the poor prognosis. Conclusions : The most common primary site of distant metastasis was lung. The poorer prognosis was highly correlated with various factors including low KPS score(<70), no postoperative adjuvant therapy, and uncontrolled primary tumors.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제7권6호
• /
• pp.1379-1397
• /
• 2013

We consider a system where a licensed radio spectrum is shared by multiple primary users(PUs) and secondary users(SUs). As the spectrum of interest is licensed to primary network, power and channel allocation must be carried out within the cognitive radio network so that no excessive interference is caused to PUs. For this system, we study the joint beamforming and power allocation problem via game theory in this paper. The problem is formulated as a non-cooperative beamforming and power allocation game, subject to the interference constraints of PUs as well as the peak transmission power constraints of SUs. We design a joint beamforming and power allocation algorithm for maximizing the total throughput of SUs, which is implemented by alternating iteration of minimum mean square error based decision feedback beamforming and a best response based iterative power allocation algorithm. Simulation results show that the algorithm has better performance than an existing algorithm and can converge to a locally optimal sum utility.

• Journal of Magnetics
• /
• 제21권3호
• /
• pp.330-339
• /
• 2016

A magnetic field sensing system with a single primary sensor and multiple reference sensors deployed locally and orthogonally, was proposed for downlink signal reception and interference cancelling for Through-the-Earth Communication (TEC). This paper mathematically analyzes a design optimization process for a search coil magnetometer (SCM), and applies that process to minimize the bandwidth of the primary SCM for TEC signal reception and the volume of reference SCMs for multiple distributions. The primary SCM achieves a 3-dB bandwidth of 7 Hz, a sensitivity threshold of 120 fT/${\surd}$Hz, and a volume of $2.32{\times}10^{-4}m^3$. The entire sensing system volume is as small as $10^{-2}m^3$. Experiments with interference from industrial frequency harmonics demonstrated an average of 36 dB and 18 dB improvements in signal-to-interference ratio and signal-to-interference plus noise ratio, respectively, using multichannel recursive-least-squares algorithm. Thus, the proposed sensing system can reduce the interference effectively and allows reliable downlink signal reception.

• Journal of Chest Surgery
• /
• 제29권5호
• /
• pp.573-576
• /
• 1996

다발성 원발성 악성종양은 두개 이상의 암이 동일 개체내에서 각각 독립해서 발생하는 것을 말한다. 저자들은 국내에서는 보고된 바가 없는 폐암, 악성 흉선종 및 방광암이 동반된 3중암 1례를 치험 하였다. 환자는 60세 남자로 호흡 곤란,흉부 불쾌감을 호소하였으며, 3개월전에 방광암 진단하에 Bricker식 수술을 받았다. 당시 시 행한 흉부 단순 사진과 전산화 단층 촬영상 대동맥 전부, 흉골 후부에 종격동 종괴와 폐의 좌하엽 후부에 폐종괴가 보였다. 수술시 좌하엽에서 폐종괴가 촉진되었으며 주위조직으로 이미 침입한흉선종이 발견되어 폐의 좌하엽 절제술및 흉선 절제술을시행하였다. 술후 1차례의 화학요법을 받았으나 더이상의 치료를 거부하고 자의 퇴원하여 약 1년 후에 사망하였다.

• Journal of Communications and Networks
• /
• 제15권1호
• /
• pp.102-110
• /
• 2013

This paper considers a cooperative orthogonal frequency division multiple access (OFDMA)-based cognitive radio network where the primary system leases some of its subchannels to the secondary system for a fraction of time in exchange for the secondary users (SUs) assisting the transmission of primary users (PUs) as relays. Our aim is to determine the cooperation strategies among the primary and secondary systems so as to maximize the sum-rate of SUs while maintaining quality-of-service (QoS) requirements of PUs. We formulate a joint optimization problem of PU transmission mode selection, SU (or relay) selection, subcarrier assignment, power control, and time allocation. By applying dual method, this mixed integer programming problem is decomposed into parallel per-subcarrier subproblems, with each determining the cooperation strategy between one PU and one SU. We show that, on each leased subcarrier, the optimal strategy is to let a SU exclusively act as a relay or transmit for itself. This result is fundamentally different from the conventional spectrum leasing in single-channel systems where a SU must transmit a fraction of time for itself if it helps the PU's transmission. We then propose a subgradient-based algorithm to find the asymptotically optimal solution to the primal problem in polynomial time. Simulation results demonstrate that the proposed algorithm can significantly enhance the network performance.