• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.54-57
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• 2002

Pretreatment technologies are defined as technologies that prepare or condition dredged material for subsequent, more rigorous treatment processes. The objectives of this study are to test the feasibility of treating dredged sediment using pretreatment process(hydrocyclone, sedimentation basin, and flotation), and to estimate design parameters for a pilot-plant design. The final goal of the project is to recycle the dredged sediment that is otherwise reused as construction materials.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권6호
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• pp.32-37
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• 2013

The scope of this study was to develop, design, and build an ex-situ remediation system of using the heating and water sparging treatment for the highly volatile DNAPL (Dense Non-Aqueous Phase Liquid) contaminated groundwater, and to conduct pilot testing at the site contaminated with DNAPL. The TCE (Trichloroethylene) removal was at the highest rate of 94.6% with the water sparging at $70^{\circ}C$ in the lab-scale test. The pilot-scale remediation system was developed, designed, and fabricated based on the results of the lab-scale test conducted. During the pilot-scale testing, DNAPL-contaminated groundwater was detained at heat exchanger for the certain period of time for pre-heating through the heat exchanger using the thermal energy supplied from the heater. The heating system supplies thermal energy to the preheated DNAPL-contaminated groundwater directly and its highly volatile TCE, $CCl_4$ (Carbontetrachloride), Chloroform are vaporized, and its vaporized and treated water is return edback to the heat exchanger. In the pilot testing the optimum condition of the HWSRS was when the water temperature at the $40^{\circ}C$ and operated with water sparging concurrently, and its TCE removal rate was 90%. The efficiency of the optimized HWSRS has been confirmed through the long-term performance evaluation process.

• 한국군사과학기술학회지
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• 제16권3호
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• pp.277-284
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• 2013

In this paper, the ventilating and heating system of T-103 trainer aircraft were investigated and redesigned to improve its poor performance. The ventilation system of the trainer was designed to increase the mass flow rate of fresh air by using air intake valves. The flow-in air through the air intake valve is supplied to the cabin by the ram effect of aircraft and the propeller. And the additional heating system was installed to improve the temperature of the cabin inside. The wasted heat from the exhaust gas of the engines was used as heat source of the additional heating system by installing an heat exchanger around the exhaust nozzle. The additional fresh air and the heated air enter the cabin via two ducts mounted under the instrument panel and behind the pedal in the cabin. The additional ventilating and heating system can be controlled by the first pilot and the secondary pilot individually using the control knob equipped separately. After mounting the additional ventilating and heating system, evaluations such as inspection of parts and component, ground run-up test, in-flight test, user test, etc. were conducted. The result of the tests was sufficient to meet the requirements of the manuals, and the pilots were satisfied with the additionally mounted systems.

• Physical Therapy Rehabilitation Science
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• 제2권1호
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• pp.39-43
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• 2013

Objective: The objective of this study is to investigate the effect of treadmill gait trainig on dynamic balance and gait functions in stroke patients. Design: Randomized, double-blind, controlled pilot study. Methods: Four subjects following first stroke participated in this study. They were divided randomly into the treadmill gait trainig group (TM group) (n=2) and the control group (n=2). Subjects in both groups received general training five times per week. Subjects in the TM group practiced an additional treadmill gait trainig program that consisted of 60 minutes, three times per week, during a period of four weeks. Timed up and go test (dynamic balance) and the GAITRite test (gait function) were evaluated before and after the intervention. Results: In dynamic balance (timed up and go test), the TM group (-14.235 sec) showed a greater decrease than the control group (-13.585 sec). In gait functions, the TM group showed a greater increase in gait speed (12.8 cm/s vs. 10.15 cm/s), step-length (5.825 cm vs. 3.735 cm), and stride-length (5.005 cm vs. 1.55 cm) than the control group. Conclusions: The treadmill gait trainig improved dynamic balance and gait functions. Further research is needed in order to confirm the generalization of these findings and to identify which stroke patients might benefit from treadmill gait trainig.

• 한국항행학회논문지
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• 제26권3호
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• pp.136-143
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• 2022

조종사의 역할은 항공사의 안전에 절대적으로 중요하다. 초기 비행훈련 단계에서 군과 민간 출신별 실제 비행에 필요한 조종사 역량 습득에 차이가 있는지를 확인하기 위해, 본 연구에서는 배경별 교육훈련의 진행상황과 효과를 분석하여 차별화된 역량기반 교육을 연구하고자 한다. 특히, 업무안배 능력은 다른 조종역량에 대한 이해가 바탕이 되어야 하여, 타 조종역량이 업무안배에 미치는 효과를 분석하여 교육 방안을 제시하고자 한다. 이를 위해 군과 민간 출신에 따라 ICAO가 정의한 8개 역량 중 정기 숙련도 점검 결과에 차이가 있는지 여부를 판단하며, 군과 민간 출신의 평균 차이 및 두 집단의 업무안배에 미치는 조종역량 요인을 분석하였다. 분석결과 업무안배에 미치는 요인으로서 의사소통 능력과 상황인식 능력이 중요한 요인으로 분석되었으며, 군출신의 경우는 상황인식 능력이 뛰어날수록 업무안배 능력이 높은 것으로 나타나는 반면, 민간출신의 경우 의사소통 능력이 뛰어날수록 업무안배 능력이 높아지는 것으로 나타남에 따라 업무안배 교육에 출신에 따른 차별화된 교육이 필요한 것으로 나타났다.

• 한국항행학회논문지
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• 제8권2호
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• pp.105-111
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• 2004

최근의 무인항공기는 정찰임무를 비롯하여 무인기에 미사일을 장착하여 지대공 공격 임무를 수행하기까지 군용으로 뿐만 아니라 기상 관측, 해상 관측 등의 목적으로 폭넓게 활용하고 있으며, 점차 필요성이 높아지고 있다. 이러한 무인기는 정밀한 자세제어를 위하여 자세정보를 제공하는 AHRS와 같은 센서를 장착하는데 비용이 500만원 정도에서 고급 센서는 수 천 만원에 이르고 있다. 최근 한국항공우주연구원에서는 이러한 고가의 센서 출력정보인 자세각 정보를 사용하지 않고 각속도 정보를 기반으로 저가형 자동비행시스템을 개발하여 소형표적기와 무인표적기 비행시험을 통하여 성능을 입증하였다. 본 논문에서는 무인항공기의 항법시스템 설계를 위하여 목표로 하는 신뢰성을 충족시키면 동시에 저가형인 GPS 센서를 선택하기 위하여 Hardware in the Loop Simulation(HILS)을 통하여 GPS 출력주파수에 따른 성능을 확인하였다. 마지막으로 무인표적기에 자동비행시스템과 항법시스템을 장착하여 비행시험을 수행하였으며, 설계된 항법시스템 성능을 비행시험 결과를 통하여 확인하였다.

• 상하수도학회지
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• 제11권1호
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• pp.88-98
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• 1997

To obtain design and operating parameters for advanced water facilities, pilot test consisted of ozonation and GAC filtration was conducted at midstream of Nakdong River. Even though the concentrations were very low, 62 chemicals were detected above $0.005{\mu}g/L$ in raw water. In the preozonation, natural organic matters which could produce THMs and organics such as phenols and amines were effectively removed. The performance of TOC removal of GAC filtration with ozonation was better than GAC filtration alone and adsorption capacity of GAC adsorbers were ranged 3~6mg-TOC/g-carbon. And also the life of GAC adsorber for removing TOC was predicted more than 1 years if ozonation is introduced. This indicates that biological degradation of organics happened in GAC filters. Most organics detected at ppt level were removed below detection limit by GAC filtration with ozonation. These results show that ozonation and GAC filtration are the reliable and safe process for organic contaminants and chlorinated byproducts control at Nakdong River.

• Physical Therapy Rehabilitation Science
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• 제11권1호
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• pp.105-112
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• 2022

Objective: Nonspecific low back pain (NS-LBP) causes pain and disability, affecting the neuromuscular system and altering gait patterns. The purpose of this study is to investigate the effect of improvement of low back pain symptoms through physical therapy on foot pressure and spatiotemporal gait parameters. Design: A pilot study. Methods: Participants received manual therapy and supervised therapeutic exercise, which consisted of 12 sessions for 6 weeks. Participants were assessed for pain intensity (a numeric pain rating scale), disability index (oswestry disability index), and spatiotemporal gait parameters before and after intervention. Wilcoxon signed rank test was used to analyze the before-and-after differences in a single group. Results: All seven NS-LBP patients completed the study without dropout. After six weeks of physical therapy, the numeric pain rating scale and oswestry disability index showed significant improvement (Z= -2.388, P=0.017). There was no significant improvement in both static and dynamic conditions in foot pressure (P>0.05). However, in the spatiotemporal gait parameters, there were significant differences in all variables except the right stance phase and left mid stance (P<0.05). Conclusions: In our pilot study, 12 sessions of physical therapy in NS-LBP patients improved gait quilty in spatiotemporal gait parameters. Similarly, it has resulted in clinically positive improvements in pain and disability.

• 유공압시스템학회논문집
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• 제3권3호
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• pp.20-24
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• 2006

Air balancer is a conveyance cargo-handling machine, used in assembly and process lines of car and machining industries. This can lift up an object, the weight of which is from 5 to 200 kg, and moves it to a position. As industrial technologies evolve, it is required to move an object and fit it into a specified position with greater accuracy, rather than performing simple tasks such as lifting objects up and down as conventional ones do. There is also a demand to handle an object with one hand, rather than with two hands,. Through designs of manifold unit for an air balancer function, pilot regulator unit to keep pressure constant, hand unit for an accurate load perception function, and air balancer circuit, this study enables everybody to work it with ease and convenience. Experiments and comparisons were conducted for the performance evaluation of the circuit.

• 대한인간공학회지
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• 제16권1호
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• pp.97-105
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• 1997

An aircraft simulator for ergonomics testing and pilot training was developed from the joint work Agency for Defense Development(ADD) and Daewoo Heavy Industry, LTD, in Korea at first time. It is basically to satisfy the requirements established by FAA-AC-120-40C ( 1995-JAN-26). The aircraft simulator will be used mainly for ergonomics testing and pilot training for basic trainer on ADD and Korea Air Force in near futrue. This simulator reproduces faithfully the cockpit and flight characteristics of the KTX-1 aircraft. It is one of the latest full flight simulators that have the CGI(computer graphic image) visual system and six degree of freedom motions system. Development efforts focused on user-oriented design approach for ergonomics testing and flight training of pilots. Main characteristics of each subsystem are described such as cockpit, instruments, control loading system, motion system, visual system, aural system, instructor operation station and aircraft simulation softwear.