• 핵의학기술
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• 제15권2호
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• pp.111-115
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• 2011

체외 검사는 각 검사 마다 6-7개의 standard 농도를 이용한 표준곡선(Dose response curve)을 사용하여 검사 결과를 분석하며, 표준곡선 사용은 진료재료 소모에 많은 부분을 차지하고 있다. 현재 원내에서 검사하는 검사항목 가운데 일부 검사 항목은, standard 농도를 이용한 환자의 검사 결과 분석수치가 대부분 낮은 결과의 분포를 보이고 있었으며, 이러한 검사 들은 마지막 standard 농도의 사용이 불필요하다고 판단하였다. 이에 낮은 검사 결과의 분포를 보이는 검사항목들을 선정하고, 마지막 standard 농도의 자리에 사용했던 진료 재료를 절감하여 진료재료의 소모비용을 줄였다. 원내 검사 항목 중 11개의 검사 항목을 진료재료 절감 대상항목으로 하였고, 검사가 진행한 횟수 만큼 마지막 standard농도에 사용되었던 진료재료(검사 Tube)를 절감할 수 있었다. 2009년 7월부터 2011년 2월까지 월별 진료재료 절감 개수, 절감 개수를 진료재료 단가로 계산하여 진료재료 절감액과, 절감된 진료재료를 환자 검사용 진료재료로 사용하여 발생한 수익을 ABC 원가계산을 근거로 산정하였다. 2009년 7월부터 2011년 2월까지 절감된 진료 재료는 3,131개였다. 이는 약 31kit의 검사 시약에 해당되는 진료재료를 절감하였다. 이것을 진료재료 단가로 계산하면 약 640만원의 진료재료비가 절감되었고, 이러한 진료 재료는 환자 검사 진료재료로 사용되어 약 1,370만원의 수익이 발생하였다. 환자의 검사 결과가 정상이거나, 낮게 분포하는 검사항목들은 마지막 standard 농도를 사용하지 않고 범위를 줄여서 검사를 진행하여도 검사 결과를 분석하는데는 영향이 없었고, standard 농도 범위 조정이 검사 결과의 신뢰성에는 영향이 없는 것으로 분석 되었다. 따라서 이 활동은 핵의학 체외검사의 진료재료 사용에 효율성을 높이고 진료재료 절감 및 병원 수익에 많은 효과가 있을 것으로 생각한다.

• 대한간호학회지
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• 제3권3호
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• pp.1-14
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• 1973

This study is designed to meet the following objectives: (1) To study attitude and behavior regarding marriage and age at marriage, (2) To learn correlates of age at marriage and to examine their relations, (3) To measure relative importance of the correlates of age at marriage, and (4) To study relations of age at marriage and family planning practice to fertility and their relative importance as correlates of fertility. The data are obtained by an independent cross-sectional survey in three study areas purposively selected to represent metropolitan. semihuman. rural population. The study population is confined to women age 17-50 as of survey. The overall response rate is 90%. Reliability of data is measured by . individual and aggregate inconsistency based upon a 15% subsample of the original interviews. The individual inconsistency (31%) is found to be high compared to the aggregate inconsistency (6%) for all 85 variables. However, the magnitude of differences between means is small, and the mean absolute shifts and proportional shifts are also small on the whole. In a word respondents did not change their answers too extremely or radically. The study populations of each study area are compared on some basic characteristics. It is found that the three study populations have more dissimilarities than similarities. The findings on seven different attitudinal positions of women toward marriage indicate that there have been tremendous changes in all study areas Iron "traditional" attitudes which have been prevalent for a long time in Korean society to "liberalized" or "modernized" attitudes. An apparent tendency is that women generally take a position of a "golden mean" attitude by not preferring either extreme of marriage attitudes. Nevertheless, the young, single, educated, and urbanite appears more "liberalized. " There has been some increase in ideal age at marriage from 1958 to 1970 for both sexes. No age group, marital status, or study area differentials in ideal age at marriage are found, the average ideal age at marriage in every sub-group being 24-25. Awareness of existing legal marriageable ages is low; only 4.4% are aware that "with parental permission: minimum age for males is 18 years and for females 16 years,"and only 3.7% are aware that "without parental permission: 27 years for males and 23 years for females." People in Korra tend to marry spouses who are in various social ways like themselves: the similarities include (a) education, occupational status of father, (c) economic status, (d) usual residence before marriage, and (e) religion. Both singulars and actual mean ages at marriage in this study confirm the trend of rising age at marriage previously established by other independent studies. The urban-rural differential in age at marriage is observed, but the differential narrows down gradually from 1935 to 1970. All socio-economic, demographic, and other variables pertaining to wife before and at first marriage, excluding (a) religion, (b) father′s of occupation, and (c) as: of menarche, are correlated with respondent's age at first marriage, whereas only three variables out of all socio-economic variables relating to husband before and at wife′s first marriage, viz., (a) education, (b) usual residence, and (c) economic level of his old home, are correlated with respondent′s age at marriage. Among socio-economic and modernity variables related to either husband or wife at the time of survey, only education and duration of residence are correlated with wife′s age at first marriage. Among the correlates of respondent′age at first marriage, education is in general the most important variable. However, it is found that wife′s education is more important than husband′s. The combined effects or the correlates studied explain no more than about 40% of variance for any of the selected groups of variables. Points which might counteract the effects of late marriage on fertility are not serious in Korea. For each of the correlates of the three fertility indices chosen for this study. namely, (a) number of living children, (b) number of live births, and (c) number of pregnancies, age at marriage is the major contributor to the variance in all age groups except the age group of 20-29 in which the index of family planning practice is the major contributor. The proportion of variability in fertility indices accounted for by the correlates is never more than 40% of the total variance in any age group. Based upon the findings from this study, it could be concluded that in the foreseeable future (a) celibate group will no! be increased to a point that would slow down population growth rate in Korea, (b) age at marriage will not increase continually, (c) although education stands out as the major contributing variable which independently explains the variation in age at marriage, it seems probable that education may not be the major variable in the near future, and (d) despite the fact found by this study that age at marriages has been the major contributor to the variance of each of the fertility indices used, family planning practice will play a more important role in the reduction of fertility in the Korean society. Therefore, factors interrupting practice of family planning must be eliminated and family planning program should be strengthened if further fertility reduction is needed.

• 간호행정학회지
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• 제2권1호
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• pp.97-114
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• 1996

INSTRODUCTION Service quality is, unlike goods quality, an abstract and elusive constuct. Service quality and its requirements are not easily understood by consumers, and also present some critical research problems. However, quality is very important to marketers and consumers in that it has many strategic benefits in contributing to profitability of marketing activities and consumers' problem-solving activities. Moreover, despite the phenomenal growth of medical service sector, few researchers have attempted to define and model medical service quality. Especially, little research has focused on the evaluation of medical service quality and patient satisfaction from the perspectives of both the provider and the patient. As competition intensifies and patients are demanding higher quality of medical service, medical service quality and patient satisfaction has emerged as a critical research topic. The major purpose of this article is to explore the concept of medical service quality and its evaluation from both nurse and patient perspectives. This article attempts to achieve its purpose by (1)classfying critical service attibutes into threecategories(satisfiers, hygiene factors, and performance factors). (2)measuring the relative importance of need criteria, (3)evaluating SERVPERF model and SERVQUAL model in medical service sector, and (4)identifying the relationship between perceived quality and overall patient satisfaction. METHOD Data were gathered from a sample of 217 patients and 179 nurses in Seoul-area general hospitals. From the review of previous literature, 50 survey items representing various facets of the medical service quality were developed to form a questionnaire. A five-point scale ranging from "Strongly Agree"(5) to "Strongly Disagree"(1) accompanied each statement(expectation statements, perception statements, and importance statements). To measure overall satisfaction, a seven-point scale was used, ranging from "Very Satisfied"(7) to "Very Dissatisfied"(1) with no verbal labels for scale points 2 through 6 RESULTS In explaining the relationship between perceived performance and overall satisfaction, only 31 variables out of original 50 survey items were proven to be statistically significant. Hence, a penalty-reward analysis was performed on theses 31 critical attributes to find out 17 satisfiers, 8 hygiene factors, and 4 performance factors in patient perspective. The role(category) of each service quality attribute in relation to patient satisfaction was com pared across two groups, that is, patients and nurses. They were little overlapped, suggesting that two groups had different sets of 'perceived quality' attributes. Principal components factor analyses of the patients' and nurses' responses were performed to identify the underlying dimensions for the set of performance(experience) statements. 28 variables were analyzed by using a varimax rotation after deleting three obscure variables. The number of factors to be extracted was determined by evaluating the eigenvalue scores. Six factors wereextracted, accounting for 57.1% of the total variance. Reliability analysis was performed to refine the factors further. Using coefficient alpha, scores of .84 to .65 were obtained. Individual-item analysis indicated that all statements in each of the factors should remain. On 26 attributes of 31 critical service quality attributes, there were gaps between actual patient's importance of need criteria and nurse perceptions of them. Those critical attributes could be classified into four categories based on the relative importance of need criteria and perceived performance from the perspective of patient. This analysis is useful in developing strategic plans for performance improvement. (1) top priorities(high importance and low performance) (in this study)- more health-related information -accuracy in billing - quality of food - appointments at my convenience - information about tests and treatments - prompt service of business office -adequacy of accommodations(elevators, etc) (2) current strengths(high importance and high performance) (3)unnecessary strengths(low importance and high performance) (4) low priorities(low importance and low performance) While 26 service quality attributes of SERPERF model were significantly related to patient satisfation, only 13 attributes of SERVQUAL model were significantly related. This result suggested that only experience-based norms(SERVPERF model) were more appropriate than expectations to serve as a benchmark against which service experiences were compared(SERVQUAL model). However, it must be noted that the degree of association to overall satisfaction was not consistent. There were some gaps between nurse percetions and patient perception of medical service performance. From the patient's viewpoint, "personal likability", "technical skill/trust", and "cares about me" were most significant positioning factors that contributed patient satisfaction. DISCUSSION This study shows that there are inconsistencies between nurse perceptions and patient perceptions of medical service attributes. Also, for service quality improvement, it is most important for nurses to understand what satisfiers, hygiene factors, and performance factors are through two-way communications. Patient satisfaction should be measured, and problems identified should be resolved for survival in intense competitive market conditions. Hence, patient satisfaction monitoring is now becoming a standard marketing tool for healthcare providers and its role is expected to increase.

• Journal of Animal Science and Technology
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• 제45권2호
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• pp.183-190
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• 2003

한우의 고급육과 관련된 비육생리를 규명하여 최적의 출하시기를 결정하고 한우 개량을 위한 종축검정에 참고자료를 제공하기 위하여1999-2000년도에 출생하고 한우 후대검정에 공시된 거세 검정우들 중 127두를 무작위 추출하여 생후 11개월령부터 24개월령 출하시까지 1개월 단위로 생체단층촬영기를 이용하여 육질을 조사하였다. 조사된 자료를 이용하여 월령별 또는 체중 증가에 따른 배장근단면적, 등지방두께 및 근내지방도의 변화를 살펴보았고 이들 측정치가 도축하여 조사된 실측치와 상관관계를 알아 보았다. 분석결과 배장근단면적의 증가는 체중의 증가와 상당히 밀접하게 관계되었으며(P<0.01) 등지방두께의 증가는 비육후기로 갈수록 월령의 이차항과 정의 관계를 보였다(P<0.01). 근내지방도의 증가는 개체의 나이와 밀접한 관계를 보였으며(P<0.01) 개체간의 변이는 생후 11개월령부터 시작되고 있었으나 17개월령 이후로 갈수록 개체간 변이 폭이 커지고 있음을 알 수 있었다. 월령별 육질 측정치가 실측정치와의 상관관계에 있어서는 나이 및 체중에 대한 보정을 실시하지 않았을 경우, 생후 17개월령 이후에 조사된 전형질에 있어서 0.6이상의 상관관계를 보이고 있었으며 22개월령 이후의 측정치와 실측치 간에는 90% 전후의 높은 상관관계를 보이고 있었다. 출하 2주 이내의 초음파 측정치와 도축 실측치와의 상관은 나이 및 체중에 대한 보정을 실시하고 추정하였을 때, 배장근단면적에 대하여는 0.91~9.92, 등지방두께에서 0.94 및 근내지방도에서 0.88으로 비교적 높게 추정되었다. 하지만 분석에 고려된 육질 관련 월령별 초음파 측정치들간에 상관은 비교적 낮게 추정되었는데 이는 적은 조사자료 및 초음파 측정의 오차 등에 기인한 것으로 사료되며 보다 많은 연구가 필요할 것으로 사료되었다. 또한 한우에 있어서 생축으로부터 육질을 판정하기 위해서는 15-17개월령 이후가 적당할 것으로 사료되었으며 22개월령 전후의 측정치는 출하시기를 결정하는데 좋은 참고자료로 사용될 수 있을 것으로 사료되었다. 한편 종축선발을 위한 육질 조기판정은 외국의 12개월령 측정치와는 달리 15개월령 측정치가 보다 타당하다고 사료되었으나 이들 측정치에 대한 유전적 변이에 대한 연구가 필요할 것으로 사료되었다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.14-14
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• 2011

W (tungsten)-alloys will be the most promising plasma facing armor materials in highly loaded plasma interactive components of the next step fusion reactors due to its high melting point, high sputtering resistance and low deuterium/tritium retention. The bonding technology of tungsten to Cu alloy was one of the key issues. In this paper, W/CuCrZr diffusion bonding has been performed successfully by inserting pure metal interlay. The joint microstructure, interfacial elements migration and phase composition were analyzed by SEM, EDS, XRD, and the joint shear strength and micro-hardness were investigated. The mock-ups were fabricated successfully with diffusion bonding and the cladding technology respectively, and the high heat flux test and thermal fatigue test were carried out under actively cooling condition. When Ni foil was used for the bonding of tungsten to CuCrZr, two reaction layers, Ni4W and Ni(W) layer, appeared between the tungsten and Ni interlayer with the optimized condition. Even though Ni4W is hard and brittle, and the strength of the joint was oppositely increased (217 MPa) due primarily to extremely small thicknesses (2~3 ${\mu}m$). When Ti foil was selected as the interlayer, the Ti foil diffused quickly with Cu and was transformed into liquid phase at $1,000^{\circ}C$. Almost all of the liquid was extruded out of the interface zone under bonding pressure, and an extremely thin residual layer (1~2 ${\mu}m$) of the liquid phase was retained between the tungsten and CuCrZr, which shear strength exceeded 160 MPa. When Ni/Ti/Ni multiple interlayers were used for bonding of tungsten to CuCrZr, a large number of intermetallic compound ($Ni_4W/NiTi_2/NiTi/Ni_3T$) were formed for the interdiffusion among W, Ni and Ti. Therefore, the shear strength of the joint was low and just about 85 MPa. The residual stresses in the clad samples with flat, arc, rectangle and trapezoid interface were estimated by Finite Element Analysis. The simulation results show that the flat clad sample was subjected maximum residual stress at the edge of the interface, which could be cracked at the edge and propagated along the interface. As for the rectangle and trapezoid interface, the residual stresses of the interface were lower than that of the flat interface, and the interface of the arc clad sample have lowest residual stress and all of the residual stress with arc interface were divided into different grooved zones, so the probabilities of cracking and propagation were lower than other interfaces. The residual stresses of the mock-ups under high heat flux of 10 $MW/m^2$ were estimated by Finite Element Analysis. The tungsten of the flat interfaces was subjected to tensile stresses (positive $S_x$), and the CuCrZr was subjected to compressive stresses (negative $S_x$). If the interface have a little microcrack, the tungsten of joint was more liable to propagate than the CuCrZr due to the brittle of the tungsten. However, when the flat interface was substituted by arc interfaces, the periodical residual stresses in the joining region were either released or formed a stress field prohibiting the growth or nucleation of the interfacial cracks. Thermal fatigue tests were performed on the mock-ups of flat and arc interface under the heat flux of 10 $MW/m^2$ with the cooling water velocity of 10 m/s. After thermal cycle experiments, a large number of microcracks appeared at the tungsten substrate due to large radial tensile stress on the flat mock-up. The defects would largely affect the heat transfer capability and the structure reliability of the mock-up. As for the arc mock-up, even though some microcracks were found at the interface of the regions, all microcracks with arc interface were divided into different arc-grooved zones, so the propagation of microcracks is difficult.

• 벤처창업연구
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• 제15권5호
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• pp.13-35
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• 2020

스타트업 액셀러레이터는 초기창업자들이 겪는 애로사항을 직접적으로 해결해 줄 수 있는 교육, 멘토링, 네트워킹, 공간, 시드머니(Seed money)등을 제공하고 일정 지분을 받는 새로운 형태의 투자주체이다(Clarysse, 2016). 스타트업 액셀러레이터들은 이들이 스타트업 생태계에 미치는 영향력이 입증되면서 전 세계적으로 확산되고 있다(Pauwels et al., 2016; Cohen & Hochberg, 2014). 본 연구는 이처럼 전 세계적으로 주요한 투자주체로 부상하고 있는 스타트업 액셀러레이터들의 투자결정요인을 도출하는 연구를 진행하였다. 먼저, 관련 선행연구가 부재한 상황이므로 정성적 메타합성법, 관련 자료조사, 관찰, 심층인터뷰의 과정을 거쳤다. 우선 창업초기 기업에 대한 투자결정요인에 대한 선행연구 30여 편을 선정하여 해당연구에 나타난 투자결정요인들을 정성적 메타합성법을 통해 비교·분석하였다. 그리고 액셀러레이터의 특성을 반영하기 위해서 액셀러레이터들의 평가과정에 대한 자료들을 조사하였으며, 실제로 이루어진 미국 액셀러레이터들의 스타트업 평가과정을 관찰하였다. 이 때 나타난 100여개의 질문을 근거이론의 코딩 기법을 활용하여 분석하였다. 더불어 미국 액셀러레이터들을 대상으로 심층 인터뷰를 진행하여 액셀러레이터의 특성과 주요 투자결정요인 등을 파악하였다. 이를 통해 최종적으로 5개 카테고리, 26개 세부 투자결정요인으로 이루어진 '액셀러레이터 형 투자결정요인'을 도출하였다. 그리고 이의 결과를 국내 액셀러레이터들의 검토를 받고 확정한 후, 국내 액셀러레이터를 대상으로 한 정량조사를 통해 각 카테고리 내, 중요도 및 우선순위를 살펴봄으로써 이의 신뢰성 및 액셀러레이터들이 중요하게 생각하는 투자결정요인 등을 확인하였다. 이렇게 액셀러레이터의 투자결정요인을 체계적으로 도출한 연구는 최초의 연구로써 후속연구들의 진행 및 스타트업 선정과정, 액셀러레이터의 투자결정 과정 등에 주요한 기여를 할 수 있으리라 기대한다.

• Asia pacific journal of information systems
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• 제21권4호
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• pp.1-25
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• 2011

Internet-based commerce has undergone an explosive growth over the past decade as consumers today find it more economical as well as more convenient to shop online. Nevertheless, the shift in the common mode of shopping from offline to online commerce has caused consumers to have worries over such issues as private information leakage, online fraud, discrepancy in product quality and grade, unsuccessful delivery, and so forth, Numerous studies have been undertaken to examine the role of perceived risk as a chief barrier to online purchases and to understand the theoretical relationships among perceived risk, trust and purchase intentions, However, most studies focus on empirically investigating the effects of trust on perceived risk, with little attention devoted to the effects of perceived risk on trust, While the influence trust has on perceived risk is worth studying, the influence in the opposite direction is equally important, enabling insights into the potential of perceived risk as a prohibitor of trust, According to Pavlou (2003), the primary source of the perceived risk is either the technological uncertainty of the Internet environment or the behavioral uncertainty of the transaction partner. Due to such types of uncertainty, an increase in the worries over the perceived risk may negatively affect trust, For example, if a consumer who sends sensitive transaction data over Internet is concerned that his or her private information may leak out because of the lack of security, trust may decrease (Olivero and Lunt, 2004), By the same token, if the consumer feels that the online merchant has the potential to profit by behaving in an opportunistic manner taking advantage of the remote, impersonal nature of online commerce, then it is unlikely that the merchant will be trusted, That is, the more the probable danger is likely to occur, the less trust and the greater need to control the transaction (Olivero and Lunt, 2004), In summary, a review of the related studies indicates that while some researchers looked at the influence of overall perceived risk on trust level, not much attention has been given to the effects of different types of perceived risk, In this context the present research aims at addressing the need to study how trust is affected by different types of perceived risk, We classified perceived risk into six different types based on the literature, and empirically analyzed the impact of each type of perceived risk upon consumer trust in an online merchant and further its impact upon purchase intentions. To meet our research objectives, we developed a conceptual model depicting the nomological structure of the relationships among our research variables, and also formulated a total of seven hypotheses. The model and hypotheses were tested using an empirical analysis based on a questionnaire survey of 206 college students. The reliability was evaluated via Cronbach's alphas, the minimum of which was found to be 0.73, and therefore the questionnaire items are all deemed reliable. In addition, the results of confirmatory factor analysis (CFA) designed to check the validity of the measurement model indicate that the convergent, discriminate, and nomological validities of the model are all acceptable. The structural equation modeling analysis to test the hypotheses yielded the following results. Of the first six hypotheses (H1-1 through H1-6) designed to examine the relationships between each risk type and trust, three hypotheses including H1-1 (performance risk ${\rightarrow}$ trust), H1-2 (psychological risk ${\rightarrow}$ trust) and H1-5 (online payment risk ${\rightarrow}$ trust) were supported with path coefficients of -0.30, -0.27 and -0.16 respectively. Finally, H2 (trust ${\rightarrow}$ purchase intentions) was supported with relatively high path coefficients of 0.73. Results of the empirical study offer the following findings and implications. First. it was found that it was performance risk, psychological risk and online payment risk that have a statistically significant influence upon consumer trust in an online merchant. It implies that a consumer may find an online merchant untrustworthy if either the product quality or the product grade does not match his or her expectations. For that reason, online merchants including digital storefronts and e-marketplaces are suggested to pursue a strategy focusing on identifying the target customers and offering products that they feel best meet performance and psychological needs of those customers. Thus, they should do their best to make it widely known that their products are of as good quality and grade as those purchased from offline department stores. In addition, it may be inferred that today's online consumers remain concerned about the security of the online commerce environment due to the repeated occurrences of hacking or private information leakage. Online merchants should take steps to remove potential vulnerabilities and provide online notices to emphasize that their website is secure. Second, consumer's overall trust was found to have a statistically significant influence on purchase intentions. This finding, which is consistent with the results of numerous prior studies, suggests that increased sales will become a reality only with enhanced consumer trust.

• 생태와환경
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• 제50권4호
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• pp.459-469
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• 2017

본 연구는 박테리아 탈질법을 이용하여 질산성 질소의 질소 및 산소의 안정동위원소 분석법을 연구하였으며, 시료 농도, 미생물 배양시간에 따른 분석값의 변화에 대하여 고찰하였다. 탈질미생물법을 이용하여 시료 내 질산염 농도가 $0.1mg\;L^{-1}$까지 질산성 질소의 산소 및 질소 동위원소 분석이 가능하였고, 0.2‰까지 정확도를 확보하였다. 환경시료(지하수) 내 질산염의 기원을 추적하기 위하여 잠재적 질소 오염원(합성비료, 축산비료)의 동위원소비를 조사한 결과, 합성비료(${\delta}^{15}N-NO_3$ -5~10‰, ${\delta}^{18}O-NO_3$ 0~15‰)는 축산비료(${\delta}^{15}N-NO_3$ 10~23‰, ${\delta}^{18}O-NO_3$ 0~20‰)와 동위원소비가 현격한 차이를 보였다. 연구지역 지하수 동위원소비와 비교한 결과, 계절별로 서로 다른 질소 오염원의 영향을 받는 것으로 여겨진다. 과거 질산염의 안정동위원소를 분석하기 위해서 다양한 방법이 시도되었다. Revesz et al. (1997)은 양이온 교환 수지를 이용한 분리법을 보고하였으며, Silva et al. (2000)와 Fukada et al. (2003)은 음이온 교환 수지를 이용한 분리법을 보고하였고, McIlvin and Altabet (2005)는 카드뮴을 이용한 화학적 변환 방법을 보고하였다. 하지만 이러한 방법에 사용되는 시약은 독성이 강하고 복잡한 전처리 과정으로 인한 긴 전처리 시간을 소요함으로 인하여 분석비용이 비싸다는 단점이 있었다. 하지만 탈질미생물법은 소량의 질산염을 이용하기 때문에 기존 방법에 비해 분석에 사용되는 시료의 부피를 1/100까지 감소시켜 과거 분석이 어려웠던 빙하, 공극수, 해수 등에 대한 분석이 가능한 장점이 있다. 수생태계로 유입되는 다양한 질소 기원을 파악하기 위하여 탈질미생물법으로 분석된 안정동위원소비를 활용한다면 효율적인 수질 관리를 위한 해석기능을 제공할 것이다. 또한, 국내 최초로 지하수 환경시료에 적용함으로써 오염 기원 추적 기법을 확립하는 데 목적을 두고 있으며, 추후 정립된 분석기법을 토대로 환경분야에서 질산성 질소의 오염 인자 판별 연구에 널리 활용되기를 기대한다.

• 대한수학교육학회지:수학교육학연구
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• 제21권4호
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• pp.327-344
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• 2011

본 연구는 고등학교 수학교과에서 배우는 모평균의 신뢰구간 구하기와 같은 통계적 추론 능력을 기르기 위한 방안의 첫 단계연구이다. 통계적 추론과정을 비판적으로 분석하여 신뢰할만한 추론방법으로 이를 인정할 수 있는 표본개념의 형성을 위해, 연구자들은 우연과 필연, 귀납과 연역, 가능성원리, 통계량의 변이성, 통계적 모형 등의 하위 개념들이 형성되어야 한다고 보았다. 그리고 초중등 통계단원의 전 과정에서 이들 개념의 체계적인 발달을 도모해야 한다는 전제 아래, 초 중 고등학교 통계단원을 분석해 본 결과는 아래와 같았다. 첫째, 문제해결 방법 선택의 지도와 관련하여, 통계적 방법을 선택할 문제 상황으로서, 우연적 상황을 필연적 상황과 구분하기위한 설명이 있는 교과서가 초등학교에는 없고, 중등 수준에서도 매우 드물었다. 둘째 표본의 모집단 관련 의미를 이해시키려는 단계적 준비가 미흡하다고 할 수 있다. 전체와 부분의 모집단과 표본 구분이 고등학교에서 비로소 공식화되고 있으며, 초 중학교에서 사용되는 표본자료는 그것으로부터 얻어지는 계산적 결과에만 초점이 맞추어짐으로서, 학년이 올라감에 따라 모집단을 향한 귀납적 추론의 신뢰성에 대한 비판적 사고의 깊이가 더해지는 모습을 찾아보기 어려웠다. 셋째, 무작위 추출이 갖는 대표성의 의미에 대한 설명보다는 무작위 활동 자체에 대한 설명이 중심이 됨으로서 무작위 추출의 확률적 의미, 즉 무작위 표본을 통해 구해질 통계량의 표집분포에서의 (상속된) 무작위성을 위한 담보로서의 목적에 대한 설명이 없다는 점이다. 넷째 통계적 추론을 수학(연역)적 추론과 구분해 주는 설명이 없을 뿐 아니라, 학습자의 논리성 발달 수준에 맞게 변화하는 가능성원리에 대한 설명, 적용 등을 전혀 찾기 어렵다는 점이다. 다섯째 통계량의 우연변이성과 그에 따른 표집분포의 존재에 대한 이해를 추구하는 설명을 찾기 어렵다는 점이다. 표집분포를 수학적으로 구하는 것은 매우 어려운 과정이지만, 그것의 존재를 인식하느냐 못하느냐는 통계적 추론 자체의 이해 가능성을 달리하는 중요한 문제이기 때문이다.

• 한국산림과학회지
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• 제94권6호
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• pp.441-445
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• 2005

기후변화 협약과 관련된 교토 의정서를 계기로 산림의 탄소 축적량을 조사하기 위하여 전국 규모의 산림 현존량 추정에 대한 연구가 진행되고 있다. 전국 규모의 산림 현존량 추정은 일반적으로 임업통계상의 임목축적 자료를 이용하고 있으며, 산림 현존량은 줄기의 건중량 대 재적 비인 줄기밀도와 임목 전체 건중량 대 줄기 건중량 비인 현존량확장계수에 의하여 산출할 수 있다. 본 연구는 한국 소나무의 대표적 생태형인 금강형 소나무와 중부지방 소나무를 대상으로 임령에 따른 줄기밀도와 현존량확장계수를 조사분석함으로써 임목축적에 의한 현존량 추정에 대한 정보를 제공하는데 목적이 있다. 금강형 소나무와 중부지방 소나무는 모두 영급이 증가함에 따라 줄기밀도가 증가하였으며, 현존량확장계수는 감소하였다. 금강형 소나무 줄기밀도의 경우 20년생 이하 영급과 40-60년생 영급 간에는 유의적인 차이가 있었으며, 중부지방 소나무의 뿌리를 제외한 지상부 현존량확장계수의 경우 20년생 이하, 20-40년생, 40-60년생 영급간에 모두 유의적인 차이가 있었다. 동일 영급에서 금강형 소나무는 중부지방 소나무에 비하여 줄기밀도와 현존량확장계수가 모두 낮은 값을 보였다. 20년생 이하와 20-40년생 영급의 경우 줄기밀도와 현존량확장계수 모두 금강형 소나무와 중부지방 소나무간에 유의적인 차이가 있었다. 이상을 종합하면, 임업통계상의 임목축적을 이용하여 소나무림의 현존량을 추정할 경우 전환계수인 줄기밀도와 현존량확장계수는 금강형 소나무와 중부지방 소나무를 구분하고 적정 범위의 영급에 따라 달리 적용함으로써 정확도를 높일 수 있는 것으로 나타났다.