This study was performed to determine the effects of genetic polymorphisms, such as glutathione S-transferase μ1 (GSTM1), glutathione S-transferase θ1 (GSTT1), glutathione S-transferase π1 (GSTP1), aryl hydrocarbon N-acetyltransferase 2 (NAT2), cytochrome P450 2E1 (CYP2E1), cytochrome P450 1A1 (CYP1A1) on the concentrations of urinary 1-hydroxypyrene (1-OHP) and 2-naphthol in general population with no occupational exposure to polycyclic aromatic hydrocarbons (PAHs). Study subjects were 257 men who visited a health promotion center in Busan. A questionnaire was used to obtain detailed data about age, smoking, drinking, body fat mass, intake of fat etc. Urinary 1-OHP and 2-naphthol concentration were analyzed by HPLC system with a fluorescence detector. A multiplex PCR method was used to identify the genotypes for GSTM1 and GSTT1. The polymorphisms of GSTP1, NAT2, CYP1A1 and CYP2E1 were determined by the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. Urinary 1-OHP concentration was higher in deleted genotype of GSTM1, increased as smoking and alcohol drinking increased. Urinary 2-naphthol concentration was also rely on the age and smoking. Neither genetic polymorphism nor drinking-related factors were significantly related to urinary 2-naphthol concentration. No significant relation was found between physical characteristics and concentrations of urinary PAHs metabolites in the subjects, but the geometric mean of urinary 1-OHP and 2-naphthol was higher in the group with higher value compared to median value. These data suggest that in general population occupationally not exposed to PAHs, urinary concentration of PAHs metabolites is influenced by smoking, alcohol drinking and deleted genotype of GSTM1 in 1-OHP and smoking in 2-naphthol.

대형여객선을 제외한 대부분의 선박에서는 정확하게 환자를 진단하고 치료할 수 있는 전문의가 없기 때문에 의료환경이 매우 열악하다. 따라서 선원에 대한 복지 및 근무환경의 개선이라는 차원에서 선택용 원적진료가 절실하고, 근무당사자 및 노조의 관심도 높아지고 있다. 본 연구는 원앙 및 연안항해에 종사하는 선박에서 환자 진료 시 중요한 정보로 활용되는 심전도와 청진음을 용이하게 측정하여 육상의 전문의사에게 전송함으로써 원격으로 진료를 수행할 수 있는 시스템을 개발하고자 하는 것이다. 본 논문에서는 기개발한 PC 기반의 디지털 심전도 및 청진기를 통하여 측정된 데이터를 국제해사위성(INMARSAT)을 이용하여 전송할 수 있는 시스템을 설계하였고, 실험을 통하여 전송 전후의 신호를 비교하여 데이터 오류를 검정하였다. 그리고 선박 통신시스템을 이용한 선박 원격의료가 가능함을 확인하였다.

심전도 측정기와 청진기를 통하여 획득된 심전도와 심음도는 비관혈적 방법으로 환자를 진단할 수 있는 생체신호이며, 의사들의 진단도구로 널리 이용되어져 왔다. 그러나 의사들이 심전도 측정기나 청진기를 이용하여 환자를 진단하는 장소는 병원 내 진료실과 응급실로 한정되어 있기 때문에, 병원에서 거리가 먼 원거리 지역이나 자동차, 비행기, 선박에서는 환자의 심음을 확인할 수 없다. 특히, 원양항해에 종사하는 선박 환자는 전문 의료진으로부터 진료를 받을 수 없는 경우가 있다. 본 논문에서는 환자의 심음 및 심전을 용이하게 측정함으로써 PC기반의 선박용 디지털 심전도 및 청진기를 개발하였으며, 해상 원격진료의 출현을 앞 당길 수 있으리라 본다.

결함검사는 생산공정에 있어서 상품의 디자인과 함께 매우 중요한 부분으로서, 상품의 경쟁력을 높이는데 필수 불가결한 것이다. 만약, 실시간 결함검출이 상품에 대한 어떤 손상도 없이 할 수 있다면, 품질 및 공정의 효율적 관리와 고비용 인력의 절감을 통하여 생산원가를 줄일 수 있다. 본 논문에서는 철판과 같은 표면에 결함이 있는 경우 필요한 정보만을 추출할 수 있는 3가지 공간필터법에 대하여 제안하였고, 공간필터의 특성을 통하여 결함검출 시스템을 구성하였다. 그리고, 최적의 표면결함 계측용 공간필터법을 개발하기 위하여 결함의 크기와 형태, 광도의 크기 및 외부 광간섭 그리고 슬리트의 개수와 같은 파라메타의 변화에 따른 측정 성능을 비교 및 분석하였다.

본 연구는 선박용 레이더로부터 디지털 신호처리보드를 통하여 영상신호를 획득하고, 일련의 디지털 신호처리 및 영상신호 분석을 통하여 선박에서 실시간으로 파향 및 파장 등의 파랑정보를 측정하기 위한 기법을 개발하고자 하는 것이다. 본 논문에서는 영상신호 분석영역 을 사용자가 직접 설정하는 기존의 방법을 개선하여 분석영역을 자동으로 설정하는 기법 및 2차원 이산 푸리에 변환을 이용한 파향분석 알고리즘에 대하여 논하였다. 그리고, 컴퓨터 시뮬레이션을 통하여 파향분석 알고리즘의 유효성을 검증하였고, 기초실험으로 다양한 해상환경에서 X밴드 레이더로 획득한 13개의 영상신호에 대하여 파향정보 분석 결과를 예시하였다.

We have reported the new measurement system which was substituted digital filter for the analog filter in order to develop the optimal system that could find the time delay between each sensors with high accuracy. And also we have confirmed through the experiments that the accuracy of measurements were differentiated by the methods what kind of digital filter had been adopted. This paper suggests two algorithms which approximate the sound source's bearing and distance. One is that sound source's relative bearing can be approximately regarded as the gradient of hyperbolic asymptote, the other is that the source's range can be approximated under the condition of a long range source relative to the sensor's interval. And a series of experiments were carried out with the source's distance 22.42meters and the random bearing interval within the limits of -90˚~+90˚. As a result, we have recognized that the approximation methods could measure the bearing and distance with higher accuracy than the method using trigonometric relation could do.

Before some experiments were carried out with analog bandpass filter which used for filtering the noise included in sound source signal. And this filter was constituted by condenser, register and operational amplifier. Hut these elements made the phase characteristics to differentiate in each sensing channel and cause a little of measurement error. We made new measurement system that was substituted digital filter for the analog filter in order to develop the optimal system which could find the time delay between each sensors with high accuracy. This paper describes the new system's constitution and the function of each parts. Specially three digital filters were designed and applied to the digital signal processing Part. And a series of experiments were carried out with the source＇s distance 9.53meters and the random bearing interval within the limits of 0˚ ~ 180˚. As a result, we have recognized that the accuracy of measurements were differentiated by the methods what kind of digital filter were adopted. And we have confirmed the facts that IIR LPF was suitable for sound source's bearing measurement and FIR LPF reduced the range measurement error.

The whistle is a very important information source for the safety navigation under foggy weather. But navigator has no concern about this, because it must be achived by human hearing sense and considered as a vague signal. If the range and relative bearing of signal source can be detected automatically, it would be very useful system for preventing marine casualties making a lot of economic loss and environment pollution. Before the algorithm of 2-dimensional sound source tracking system was reported. This paper describes the method that can obtain the time lag between three signals and the theory of cross-correlation analysis and subtraction method for cauculating the time lag by using the digital signal data sequences. And a series of experiments were carried out for various position of sound source in the range from 200cm to 530cm. As a result, we have recognized that sound source tracking system is possible to the sea field with improvement of position error.

The question style in high school environmental science textbook was examined in terms of the placement, frequency, and type of question, and then analyzed the kind of scientific inquiry process elicited by the question in the topic of textbook using the Textbook Questioning Strategy Assessment Instrument (TQSAI). The average number of question per topic was only 0.6. The number of all question in the high school environmental science textbook was very little ; the number of non-experiential question was 8 and that of experiential one was 3. The total number of sentence was 1,236 and the ratio of the number of question to that of sentence was 0.9%. The frequency of non-experiential question was higher than that of experiential one. In action part of the textbook, there were more kinds of question styles than in the main part.

When navigating in or near an area of restricted visibility, it is necessary to be heard the whistle, bell and/or the siren of lighthouses or ships at times. Even though we can get the brief informations about the property of sound, the direction and range of a sound radiator, it is not enough to get the accurate informations for decision making. Generally the audio frequency is known as 16~20, 000Hz, but the earshot is shorten and discrimination of sound is more difficult when there is some noise. The sound pressure is 60dB at the moment when human speaks 1 meter away. Usually the noise pressures are 40dB in a silent room and 60dB on the quiet street, respectively. It this study, the basic algorithm and a method of signal processing are suggested to trace the direction and range of the source radiator using the signals received through not a physical sense but the microphone sensors.