• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.654-661
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• 2000

Area of greenhouse increases rapidly up to 45,265ha by the year of 1998 in Korea. Hot air heater with light oil combustion is the most common heater for greenhouse heating in the winter season. However, exhaust gas heat discharged to atmosphere through chimney reaches up to 10~20% of total heat of the oil combusted in the furnace. In order to recapture the heat of this exhaust gas and to recycle for greenhouse heating, the heat pipe type exhaust heat recovery system was manufactured and tested in this experiment. The exhaust heat recovery system was made for space heating in the greenhouse. The system consisted of a heat exchanger made of heat pipes, ${\emptyset}15.88{\times}600mm$ located in the rectangular box of $600{\times}550{\times}330mm$, a blower and air ducts. The rectangular box was divided by two compartments where hot chamber exposed to exhaust gas in which heat pipes could pick up the heat of exhaust gas, and by evaporation of the heat transfer medium in the pipes it carries the heat to the cold compartment, then the blower moves the heat to greenhouse. The number of heat pipe was 60, calculated considering the heat exchange amount between flue gas and heat transfer capacity of heat pipe. The working fluid of heat pipe was acetone because acetone is known for its excellent heat transfer capacity. The system was attached to the exhaust gas path. According to the performance test it could recover 53,809 to 74,613kJ/hr depending on the inlet air temperature of 12 to $-12^{circ}C$ respectively when air flow rate $1,100\textrm{m}^3/hr$. The exhaust gas temperature left the heat exchanger dropped to $100^{circ}C$ from $270^{circ}C$ by the heat exchange between the air and the flue gas, the temperature difference was collected by the air and the warm air temperature was about $60^{circ}C$ at the air flow rate of $1,100\textrm{m}^3/hr$. This heat pipe type exhaust heat recovery system can reduce fuel cost by 10% annually according to the economic analysis.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2523-2526
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• 2012

Introduction: Febrile neutropenia is a relatively frequent event in cancer patients treated with chemotherapy and improvement in absolute neutrophil count (ANC) has been linked directly to improved outcome. Evaluation of granulocyte colony stimulating factors (GCSFs) for treatment has shown reduced incidences of episodes of prolonged neutropenia and protracted hospitalization. To determine absolute neutrophil counts with GCSF in febrile neutropenic cancer patients admitted to a tertiary care centre and to co-relate the improvement in ANC with mortality and hospital discharge. Methods: A prospective cross sectional study was carried at an oncology ward at Aga Khan University hospital from January 2010 to June 2011. All adult patients who were admitted and treated with GCSF for chemotherapy induced febrile neutropenia were included. Multivariable regression was conducted to identify the factors related with poor outcomes. Results: A total of 131 patients with febrile neutropenia were identified with mean age of 43.2 (18-85) years, 79 (60%) being ${\leq}50$. Seventy-five (57%) had solid tumors and 56 (43%) hematological malignancies, including lymphoma. Fifty seven (43.5%) had an ANC less 100 cells/$mm^3$, 34 (26%) one between 100-300 cells/$mm^3$ and 40 (31%) an ANC greater than 300 cells/$mm^3$. Thirty (23%) patients showed ANC recovery in 1-3 days, and 74(56%) within 4-7 days. Thirteen (10%) patients showed no recovery. The overall mortality was 18 (13.7%) patients. The mean time for ANC recovery seen in hematological malignancies was 6.34 days whereas for solid tumors it was 4.88 days. Patients with ANC <100 cells/$mm^3$ were more likely to die than patients with ANC >300 cells/$mm^3$ by a factor of 4.3. Similarly patients >50 years of age were 2.7 times more likely to die than younger patients. Conclusion: Our study demonstrated that use of GCSF, in addition to intravenous antibiotics, in treatment of patients with chemotherapy induced febrile neutropenia accelerates neutrophil recovery, and shortens antibiotic therapy and hospitalization. We propose to risk classify the patients at the time of admission to evaluate the cost effectiveness of this approach in a resource constrained setup.

• Korean Chemical Engineering Research
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• 제59권1호
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• pp.60-67
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• 2021

본 연구에서는 CO2 포집을 포함하는 500 MWe 급 전기를 생산하는 순산소 석탄화력발전소에 대한 공정흐름도를 제시하였고, 기술경제성 평가를 수행하였다. 이 석탄화력발전소는 순환 유동층 보일러(CFB), 초초 임계 증기 사이클 증기 터빈, 보일러에서 배출되는 배기가스내 수분과 오염물질을 제거하는 배기가스 정제 장치(FGC), 산소 분리 초저온 공정(ASU), 이산화탄소를 분리하는 극저온 공정(CPU)을 포함한다. 건식 배기가스 재순환(FGR)은 CFB연소기내 온도 제어와 고농도 CO2 배출을 위하여 사용되었다. 이 순산소 석탄화력발전소의 열효율을 증가시키기 위하여 FGR 흐름에 대한 열교환, ASU에서 배출되는 질소 흐름에 대한 열교환, 그리고 CPU 내 기체 압축기의 열 회수를 고려하였다. FGR열교환기의 온도차(ΔT)의 감소는 배기가스의 더 많은 폐열 회수를 의미하며, 전기 및 엑서지 효율을 증가시켰다. FGR열교환기의 ΔT가 10 ℃ 에서 FGR과 FGC 주변의 연간 비용이 최소가 되었다. 이때, 전기 효율은 39%, 총투자비는 1371 M$, 총생산비용은 90 M$, 그리고 투자수익률은 7%/y, 그리고 투자회수기간은 12년으로 예측되었다. 본 연구를 통하여 순산소 석탄화력발전소의 열효율 향상을 위한 열교환망이 제시되었고, FGR 열교환기의 최적 운전 조건이 도출되었다.

• Journal of Communications and Networks
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• 제8권2호
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• pp.228-233
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• 2006

Survivability is a very important requirement for the deployment of broadband networks because out of service links can affect volumes of traffic even if it is a very short time. And the data paths of broadband networks, which are critical for traffic engineering, are always necessary to be well protected. The procedure of protection or restoration for a path is initiated when failure is detected within the working path. In order to minimize the influence on transmission quality caused by the failure of links and to provide a definite time for the recovery from the failure, the protection switching time (PST) should be carefully considered in the path arrangement. Several researches have been devoted to construct the protection and restoration schemes of data paths over dense wavelength division multiplexing (DWDM) networks, however, there was rare research on the design of data paths with guaranteed protection switching time. In this paper, the PST-guaranteed scheme, which is based on the concept of short leap shared protection (SLSP), for the arrangement of data paths in DWDM networks is proposed. The proposed scheme provides an efficient procedure to determine a just-enough PST-guaranteed backup paths for a working path. In addition to selecting the PST-guaranteed path, the network cost is also considered in a heuristic manner. The experimental results demonstrate that the paths arranged by the proposed scheme can fully meet the desired PST and the required cost of the selected path is competitive with which of the shared path scheme.

• 센서학회지
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• 제25권3호
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• pp.196-201
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• 2016

Rehabilitation exercises are the treatments designed to help patients who are in the process of recovery from injury or illness to restore their body functions back to the original status. However, many patients suffering from chronic diseases have found difficulties visiting hospitals for the rehabilitation program due to lack of transportation, cost of the program, their own busy schedules, etc. Also, the program usually contains a few medical check-ups which can cause patients to feel uncomfortable. In this paper, we develop a remote rehabilitation system with bio-signals by a stereo camera. A Kinect stereo camera manufactured by Microsoft corporation was used to recognize the body movement of a patient by using its infrared(IR) camera. Also, we detect the chest area of a user from the skeleton data and process to gain respiratory status. ROI coordinates are created on a user's face to detect photoplethysmography(PPG) signals to calculate heart rate values from its color sensor. Finally, rehabilitation exercises and bio-signal detecting features are combined into a Windows application for the cost effective and high performance remote rehabilitation system.

• The Journal of Korean Physical Therapy
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• 제27권2호
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• pp.118-123
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• 2015

Purpose: This study was conducted in order to present basic policy data for introduction of a home-based physical therapy (HBPT) policy. Methods: The study surveyed physical therapists and patients for six weeks, in order to identify satisfaction with physical therapy. The statistical significance of the management plan with regard to costs and cost estimation and payment methods was determined and managed according to the operating principals of HBPT, eligibility criteria, number of visits, treatment time, and team approach. Results: Through the survey all groups of patients and physical therapists recognized the need for HBPT. They felt that the most desirable methods for activation of physical therapy visits involve precise diagnosis and evaluation through a team approach. While making regular visits to the patient three times a week, an expert visiting physical therapist with 3 to 5 years of experience in the clinical field could provide central nerve developmental treatment in less than 60 minutes; this service could be provided at a reasonable cost, minimizing unnecessary hospital visits, reducing time, medical expenses and facilitating a quick recovery due to psychological satisfaction resulting from a decrease in the psychological anxiety patients often experience in medical institutions. Conclusion: Based on the study results provided above, if HBPT is to be introduced, appropriate pricing and programs should be based on the results of pilot projects.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2006년도 추계공동학술대회
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• pp.373-383
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• 2006

Logistics is one of the most important factors to manage a stream of materials in economic environment. Establishing effective logistics system needs to consider some constraints which are fluctuation of materials volume, a long distance between makers and consumers, one way logistics and small quantity batch production. It is estimated that Unit Load System should be a powerful method to cope with those problems. It helps to realize the key issues which are Standardization and Logistics Pool System The Material Unification of Logistics System is able to participate in all kinds of industries including manufacturing, distribution and logistics. This system has some merits which are a long distance transportation cost down, product recovery, and treatment in the unbalance of demand and supply caused by unstable materials volume. Four strategies of Material Logistics Model are Packing Rationalization, Logistics Pool System, JIT System application and establishing effective infrastructure. The Material Unification Of Logistics System based on Unit Load System achieves efficiency of logistics and largely decreases moving cost.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 추계종합학술대회
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• pp.142-145
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• 2001

본 논문에서는 PSTN과 PSDN망의 통합 망 설계 기술에 대하여 연구하였다. 망 구조모델은 소프트 스위칭과 액세스 게이트 웨이을 이용함으로써, 기존의 SONET기반 네트워크가 제공해줄 수 없는 대역폭 대비 사용료와 실시간/웹기반의 다양한 서비스를 창출할 수 있다. 또한 각 영역의 수행기능과 지역 망의 가입자 구축에 있어서 각 망을 지역권으로 구분함으로써 망복구능력이 탁월하다. 전용망 사용비용으로 대체되기 때문에 통신비용의 대폭적인 절감과 부수적으로 자체적인 통신망 활용을 극대화할 수 있다는 것이다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.376-379
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• 2005

High efficiency and low cost sustain driver for plasma display panel (PDP) with current fed is proposed. Main concept of the proposed circuit is using the current source to charge and discharge panel. As a result, all power switches can achieve the zero voltage switching (ZVS) and every auxiliary switch can also do the zero current switching (ZCS). Moreover, since the inductor current can compensate the discharge current, the current stress of all power switches can be reduced considerably. Furthermore, it has features as a simpler structure, less mass, less cost, and lower electromagnetic interference than prior circuit.

• 정보처리학회논문지C
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• 제12C권3호
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• pp.401-408
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• 2005

본 논문에서는 백업 경로 비용을 최소화하여 네트워크 자원을 효율적으로 사용하며 복구 성능을 높일 수 있는 MPLS 복구 방안을 제시한다. 기존의 다른 복구 방안과 달리, 제안 복구 방안에서의 복원 시도 절차는 작업 LSP 설정 시 정해진 특정 노드로부터 시작한다. LSP 설정 메시지가 작업 경로를 설정하면서 복구 비용을 산출하고 복구 시작 노드를 정해 준다. 그렇게 함으로써, 복구 속도가 빨라지고 망의 자원 활용도가 높아질 수 있다. 제안 방안을 시뮬레이션을 통해 기존의 다른 복구 방안 및 보호 방안과 비교하였다. 실험 결과 제안 방안이 비교적 적은 지연과 손실 특성을 가지면서 빠른 복구 성능을 보여줌을 확인하였다.