• Journal of Intelligence and Information Systems
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• v.19 no.2
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• pp.1-20
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• 2013

Nowadays, social network is a huge communication platform for providing people to connect with one another and to bring users together to share common interests, experiences, and their daily activities. Users spend hours per day in maintaining personal information and interacting with other people via posting, commenting, messaging, games, social events, and applications. Due to the growth of user's distributed information in social network, there is a great potential to utilize the social data to enhance the quality of recommender system. There are some researches focusing on social network analysis that investigate how social network can be used in recommendation domain. Among these researches, we are interested in taking advantages of the interaction between a user and others in social network that can be determined and known as social relationship. Furthermore, mostly user's decisions before purchasing some products depend on suggestion of people who have either the same preferences or closer relationship. For this reason, we believe that user's relationship in social network can provide an effective way to increase the quality in prediction user's interests of recommender system. Therefore, social relationship between users encountered from social network is a common factor to improve the way of predicting user's preferences in the conventional approach. Recommender system is dramatically increasing in popularity and currently being used by many e-commerce sites such as Amazon.com, Last.fm, eBay.com, etc. Collaborative filtering (CF) method is one of the essential and powerful techniques in recommender system for suggesting the appropriate items to user by learning user's preferences. CF method focuses on user data and generates automatic prediction about user's interests by gathering information from users who share similar background and preferences. Specifically, the intension of CF method is to find users who have similar preferences and to suggest target user items that were mostly preferred by those nearest neighbor users. There are two basic units that need to be considered by CF method, the user and the item. Each user needs to provide his rating value on items i.e. movies, products, books, etc to indicate their interests on those items. In addition, CF uses the user-rating matrix to find a group of users who have similar rating with target user. Then, it predicts unknown rating value for items that target user has not rated. Currently, CF has been successfully implemented in both information filtering and e-commerce applications. However, it remains some important challenges such as cold start, data sparsity, and scalability reflected on quality and accuracy of prediction. In order to overcome these challenges, many researchers have proposed various kinds of CF method such as hybrid CF, trust-based CF, social network-based CF, etc. In the purpose of improving the recommendation performance and prediction accuracy of standard CF, in this paper we propose a method which integrates traditional CF technique with social relationship between users discovered from user's behavior in social network i.e. Facebook. We identify user's relationship from behavior of user such as posts and comments interacted with friends in Facebook. We believe that social relationship implicitly inferred from user's behavior can be likely applied to compensate the limitation of conventional approach. Therefore, we extract posts and comments of each user by using Facebook Graph API and calculate feature score among each term to obtain feature vector for computing similarity of user. Then, we combine the result with similarity value computed using traditional CF technique. Finally, our system provides a list of recommended items according to neighbor users who have the biggest total similarity value to the target user. In order to verify and evaluate our proposed method we have performed an experiment on data collected from our Movies Rating System. Prediction accuracy evaluation is conducted to demonstrate how much our algorithm gives the correctness of recommendation to user in terms of MAE. Then, the evaluation of performance is made to show the effectiveness of our method in terms of precision, recall, and F1-measure. Evaluation on coverage is also included in our experiment to see the ability of generating recommendation. The experimental results show that our proposed method outperform and more accurate in suggesting items to users with better performance. The effectiveness of user's behavior in social network particularly shows the significant improvement by up to 6% on recommendation accuracy. Moreover, experiment of recommendation performance shows that incorporating social relationship observed from user's behavior into CF is beneficial and useful to generate recommendation with 7% improvement of performance compared with benchmark methods. Finally, we confirm that interaction between users in social network is able to enhance the accuracy and give better recommendation in conventional approach.

• The korean journal of orthodontics
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• v.24 no.3 s.46
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• pp.569-586
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• 1994

The purpose of this study is to investigate the effect of loss of incisal function on the thickness, growth activities, ultrastructure of the condylar cartilage and on the muscle fibers of masseter superlicialis, anterior belly of digastric muscle in the growing rats. 37 day-old-rats of which incisors had been trimmed every day received soft diet from weaning and were studied by the autoradiography, electron microscopy and muscle histochemistry. The results obtained were as follows : The thickness of the fibrous, proliferative layer in superior, posterosuperior portion of the condylar cartilage was significantly(p<0.01) reduced in experimental groups and the decrease rate of fibrous layer thickness was greater in posterosuperior portion than in superior portion of cartilage and was greater than in proliferative layer. In normal group, more cells of posterosuperior portion moved more rapidly towards the medullary cavity. In experimental group, the labelling index of posterosuperior portion was decreased in proliferative layer at 2 hours, in transitional layer at 1, 2 days, in hypertrophic layer at 4 days after injection relative to posterosuperior portion of control group. But labelling index of superior portion was not different from that of control group at all time course after injection. From the muscle histochemistry, the diameter of type IIB fibers in masseter superficialis muscle, type IIA, type IIB fibers in anterior belly of digastric muscle decreased significantly(p<0.01) relative to controls in experimental group. From electron microscopic study, in the fibrous layer of the posterosuperior portion of condylar cartilage in normal group, many fibroblast like cells near the joint cavity showed extensive remodelling activities in ultrastructure. There was no morphological changes between experimental and control group in all cartilage cell layers of superior portion but cells near the joint cavity in fibrous layer of posterosuperior portion of experimental group showed morphologically inactive state relative to control group.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.23-29
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• 2017

The packaged optical fiber Bragg grating sensors which were networked by multiplexing the Bragg grating sensors with WDM technology were investigated in application for the structural health monitoring of the marine trestle structure transporting the ship. The optical fiber Bragg grating sensor was packaged in a cylindrical shape made of aluminum tubes. Furthermore, after the packaged optical fiber sensor was inserted in polymeric tube, the epoxy was filled inside the tube so that the sensor has resistance and durability against sea water. The packaged optical fiber sensor component was investigated under 0.2 MPa of hydraulic pressure and was found to be robust. The number and location of Bragg gratings attached at the trestle were determined where the trestle was subject to high displacement obtained by the finite element simulation. Strain of the part in the trestle being subjected to the maximum load was analyzed to be ${\sim}1000{\mu}{\varepsilon}$ and thus shift in Bragg wavelength of the sensor caused by the maximum load of the trestle was found to be ~1,200 pm. According to results of the finite element analysis, the Bragg wavelength spacings of the sensors were determined to have 3~5 nm without overlapping of grating wavelengths between sensors when the trestle was under loads and thus 50 of the grating sensors with each module consisting of 5 sensors could be networked within 150 nm optical window at 1550 nm wavelength of the Bragg wavelength interrogator. Shifts in Bragg wavelength of the 5 packaged optical fiber sensors attached at the mock trestle unit were well interrogated by the grating interrogator which used the optical fiber loop mirror, and the maximum strain rate was measured to be about $235.650{\mu}{\varepsilon}$. The modelling result of the sensor packaging and networking was in good agreements with experimental result each other.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1512-1517
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• 2011

Effects of cultivated area on antioxidant compounds and antioxidant activities of sorghum were determined. The cultivated areas were Miryang (plain area of interior), Wonju (mountainous territory), and Sinan (coastal area), and the cultivated varieties were Hwanggeumchal-susu (HGCS), Daepung-susu (DPS), Whinchal-susu (WCS), Tojong-susu (TJS), and Mae-susu (MS). The highest total polyphenol contents of methanolic extracts were 19.64 and 19.32 mg gallic acid equivalent (GE)/g in un-hulled MS and DPS on the cultivated Wonju. The highest total flavonoid content was 7.54 mg catechin equivalent (CE)/g in un-hulled DPS on cultivated Wonju. Generally, antioxidant compound contents of sorghum on cultivated Wonju were higher than those of Miryang and Sinan. Further, un-hulled HGCS, DPS, and MS were higher than un-hulled WCS and TJS. The DPPH and ABTS radical scavenging activities of the methanolic extracts of sorghum did not significantly change with the cultivated areas, whereas there were significant changes with cultivated varieties. The radical scavenging activities of un-hulled HGCS, DPS, and MS with red or dark brown seed coats were higher than those of un-hulled WCS and TJS with white seed coats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.4
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• pp.570-576
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• 2014

Response surface methodology (RSM) was applied to optimize the microwave-assisted extraction (MAE) conditions for electron-donating ability, total phenol content, and total flavonoid content of Ligustrum lucidum Aiton. Ligustrum lucidum Aiton from different regions was tested, and Ligustrum lucidum Aiton from Haenam was chosen due to its higher total phenolic content, total flavonoid content, DPPH radical scavenging activity and ABTS radical scavenging activity compared to the other samples. Central composite design was used to optimize extraction of Ligustrum lucidum Aiton from Haenam as well as determine the effects of extraction temperature ($X_1$) and extraction time ($X_2$) on dependent variables ($Y_n$). Determination coefficients ($R^2$) of the regression equations for dependent variables ranged from 0.8858 to 0.9517. The optimum points were $131.68^{\circ}C$ for extraction temperature and 5.49 min for extraction time. Predicted values of the optimized conditions were acceptable when compared to experimental values.

• The Korean Journal of Health Service Management
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• v.2 no.1
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• pp.37-55
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• 2008

This study aims to enhance work efficiency and satisfaction by offering data that make a physical therapist cope with stress coming from the job efficiently by identifying and analyzing the job satisfaction and work stress perceived by a physical therapist, and the level of reaction of a physical therapist. The study distributed survey questionnaires to 300 physical therapists working in medical institutions in Busan via mail and by visit from March 3, 2007 by selecting them simply and randomly from the physical therapist list, and collected the questionnaires by March 20, 2007, 103 respondents were working at 17 general hospitals including a university hospital, 65 respondents at 12 medical centers, and 79 respondents at 39 doctor's offices. The study collected 251 copies, which showed the collection rate of 83.7%, and analyzed 247 copies (82.3%) excluding 4 copies of insincere answers. As a research tool for measuring job satisfaction the study used a tool employed for research into the job satisfaction of physical therapists who work at medical institutions in Gwangju, Jeonnam, and Jeonbuk by Kim Hee-Gwon(1992) and research regarding job satisfaction by Jeong Jeong-Hee(2004) as well as research regarding the factors of job satisfaction by Flippo(1980) & Seberhagen(1970) after adjusting the research tools to the purpose of the study. Also for questions about work stress, the study employed nurses' job stress measurement tool developed by Kim Mae-Ja and em Mi-Ok(1984) by modifying the tool to the purpose of the study, and for a measurement tool for reaction to stress, the study used a tool employed for research into reaction to stress of nurses at general hospitals by Choi Eun-Deok(2005) without modification. For data analysis, the study used the SPSS12.0 as a statistical method, and then used t-test or ANOVA for verifying actual numbers, percentile, average :score, standard deviation, rank, and difference. Also, the study conducted which is a post-test method for variables that show a significant difference at the level of p<.05 level after the analysis. The findings include the following. 1) The respondents' job satisfaction score was 3.21 points on the average (out of 5 full points). The peer relationship ranked the highest, posting 4.02 points on the average, and the job satisfaction with rewards was proven the lowest, posting 2.51 points. For the job satisfaction level by characteristics, there were significant differences (p<.05) in gender, hospital type, weekly working hours, monthly working days, number of patients per day, department in charge of therapy, and number of peers, and there was no significant difference in characteristics other than that. 2) The respondents' work stress score was 2.72 points (out of 5 full points) on the average. The respondents were shown to be under the highest stress when they suffered from excessive workload, posting 3.49 points on the average, and they were shown to be under the least stress when they had a conflict with peers at another department, recording 1.90 points on the average. for the job stress level by the characteristics of job, there was a significant difference in the reflection of job assessment(p<.05). 3) 1n respondents' reaction to stress, most of them were shown to make efforts in coping with stress, posting 2.80 points (out of 5 full points). For their experience of being wider stress, they answered that 'they felt depressed (2.85 points)" for their experience of coping with stress, they answered that 'they were indifferent to it or thought about something else' (2.62 points). Also, for their efforts in coping with stress, they answered that 'they were motivated to remove their strain by taking leave, playing, or using their preferences' (3.52 points), which ranked higher. For the level of reaction to stress by characteristics, there were significant differences by age, gender, marital status, total service years as a physical therapist, monthly working days, and department in charge of therapy(p<.05). It is necessary to offer correct information by conducting an in-depth analysis of the stressful situations of physical therapists who exert efforts in rehabilitating patients at hospitals by factor, and seeking management plans based on the research results. Also, it is necessary to develop a program for coping with stress efficiently for removing stress and to conduct research into the understanding and cooperation of administrators and persons in charge of physical therapists for reducing physical therapists' stress at hospitals.

• Journal of Life Science
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• v.26 no.11
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• pp.1237-1244
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• 2016

A comprehensive analysis of the genetic diversity and relationship of the cold-water fishery walleye pollock (Theragra chalcogramma), the most abundant economically important fishery resource in the East sea of Korea, has not been carried out, despite its importance in Korea. The present study assessed the genetic diversity and relationship between five walleye pollock populations (Korean population, Russian population, USA population, and Japanese populations) of T. chalcogramma using eight microsatellite DNA (msDNA) markers to provide the scientific data for the preservation and management of the Pollock fishery resource. The results of the analysis of 186 individuals of the Pollock revealed a range of 7.13-10.63 numbers of alleles (mean number of alleles=9.05). The means of observed heterozygosity ($H_O$), expected heterozygosity ($H_E$) were 0.732 and 0.698, respectively. The results of genetic distance, Pairwise $F_{ST}$, UPGMA (UPGMA: un-weighted pair-group method with an arithmetical average) (the phylogenetic tree), PCA (PCA: Principal Coordinate analysis) analysis pointed to significant differences between the Korean population, Russian population, USA population, and Japanese populations, although small (p<0.05). These results shed light on the genetic diversity and relationships of T. chalcogramma and can be utilized for research on the evaluation and conservation of Korean T. chalcogramma as genetic resources.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.12 no.1
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• pp.63-73
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• 2006

The first packaging of Korean market milk dates back to July 1937 when Seoul Dairy Co-operative (Kyung Seong Dairy Co-operative in those days) used 1 hob (180 ml) glass bottles with either paper caps or cork caps. During 1945-1972, 2 hob (360 ml) glass bottles were produced, and iron caps and egret-shaped plastic film replaced the previously used caps. When there were insufficient numbers of milk bottles, other glass bottles such as soda drink bottles and beer bottles were used instead. Seoul Dairy Co-operative was the only dairy company existing in Korea until Nam Yang Dairy Co. Ltd was founded in March 1964, followed by Hae Tae Dairy Co. Ltd(Tae Han Food Public Corporation in those days) in 1969 and Mae-il Dairy Co. Ltd (Korea Dairy Company in those days) in May 1971. As many other dairy companies along with the above-mentioned companies were established, a variety of dairy products were packaged and marketed. In 1971 Seoul Dairy Co-operative first used triangular-shaped polyethylene film wrappers, and in 1972 Nam Yang Diary was the first company importing sterilized Tetra pak for the packaging of milk. Since 1974 rectangular shaped polyethylene film wrappers and plastic bottles were used. In 1977 the gable top carton pack made of paper was first introduced by Seo Joo Industry Co. Ltd, and its market share increased rapidly with gradual increase in its volume, from 180ml to 200ml, to 250ml, to 500ml and finally to 1,000ml, causing change in the volume of milk consumption. And in Sep. 1987 Pasteur market milk Co. Ltd. first used round type high density polyethylene bottle(body) with low density polyethylene cap of 245g, 490g and 980g volumes respectively.

• Asian Oncology Nursing
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• v.1 no.2
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• pp.191-203
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• 2001

The health of a nurse is very important because her mental and physical health can influence toward nursing patients directly, Especially, Cancer patients are growing annually. Also, terminal cancer patients' nursing and dead place are increasingly using hospital and the period of nursing for cancer patients are increasing. Nursing for cancer patients are different with acute disease. Therefore, I analysed comparing nurses' health working in cancer and general ward so that nurses working at cancer ward could be developed as a professional nurse, and I wanted to establish the foundation of nursing administration and reasonable manpower management to supply good quality of nursing to patients. In my research, I selected 117 nurses working in cancer ward and 134 nurses working in general word to analyse the stress rate and nurse's health comparing nurses working in general ward and cancer ward. The survey was conducted of nurses working in cancer ward nurses in 2 university hospitals, nurses working in a cancer hospital, and general ward nurses working in 3 public hospital. Also, the data was collected from Sep. 13, 2001 to Sep. 28, 2001. As health measuring tool, I used Cornell Medical Index(CMI) which are developed to fit Koreans by Ko Ungrin and Park Hang-bas (1980) using Cornell Medical Services which were designed by Weiser, Brosman, Mittelman, Wechler, Wolff in Cornell University(1945). As working stress measuring tool, I used Questionaries which were designed by Kim Mae-ja and Ku Mi-ok(1984) and then developed by Bae In-sook(1996). For managing the data, I used frequency, percentage, ${\chi}^2$ verification, t-test, and F-test (ANOVA). And in the case of significant data(p<.05). I did Duncan's test for post verification. The mutual relation between health condition and working stress rate have been conducted using Pearson's Correlation Coefficient. Followings are the results of my research. 1. Two groups showed significant differency at age after testing homogeneous character between two groups (${\chi}^2$ =9.919, p=.007). 2. Comparing two group's health condition, cancer ward(average 19.35${\pm}$18.34) were higher than general ward(14.42${\pm}$10.59) and showed statistical significant differency(p=.009). And, comparing two group's mental condition, cancer ward(9.00${\pm}$9.79) were higher than general ward(7.13${\pm}$6.35) and statistically no differency. 3. After comparing two group's working stress rate, the rate of cancer ward nurse's working stress(3.36${\pm}$.50) is higher than general ward nurse (3.32${\pm}$.48). There are no significant differency. However, in the detailed verification test, there were significant differency at inappropriate compensation (t=3.254, p=.001) and medication issue (t=2.170, p=.031). 4. After comparing health condition at general points, physical health condition showed significant differency at age(p=.020), the number of children (p=.015), religion (p=.015), position(p=.005), career(p=.008), working satisfaction(p=.003), activity after office hour(p=.045); and mental health condition showed significant differency at position(p=.010), career (p=.017), working satisfaction (p=.003). 5. After comparing the working stress rate according to general points, there were significant differency at working satisfaction (F=5.285, p=.006), predicted nursing(F=3.822, p=.023). 6. At the relation of health condition and working stress rate between two groups. physical and mental condition showed significant relation with working stress rate. i.e, if a nurse's health condition is not good, she are feeling much more stress than others. After considering all the factors in my research, I found that the health condition and stress rate of cancer ward nurses is much higher than general ward nurses. Considering that cancer ward nurses is necessary to care for increasing cancer patients with mental and physical nursing, the less stress for cancer ward nurses is very important to develop nursing quality and working efficiency by keeping good health condition, specializing cancer ward nurses. Therefore, we need following studies to find the factors which are effecting to cancer ward nurses' health and specialization. Also, we need to improve managing working condition to decrease working stress by improving working condition.

• The Korean Nurse
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• v.31 no.2
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• pp.51-69
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• 1992

Grief that is not acknowledged and worked through may manifest itself in some emotional, mental or physical problem. In recent years much has been learned about coping with grief which the hospice program can utilize to help family members cope with their grief. This study was carried out to determine the helpfulness of the bereavement care of Severance Hospice and to learm more about the grief response of the bereaved. The tools used to collect data were an assessment form used in the bereavement program and the Grief Experience Inventory developed by Sanders and revised and translated 'by the researcher. Data was obtained from bereaved family members(54 for the final grief assessment and 39 for the grief response assessment) receiving bereavement follow-up, from July 1989 to March 1991. Results of the study were as follows: 1. Final Grief Assessment Regarding the resolution of their grief the majority of the bereaved accepted the reality of the death of their family member, while slightly more than three-quarters were able to express their feelings toward their loss. A large majority had returned to activities of daily living well or fairly well and had reinvested their energy in a person other than the deceased. In addition, the physical condition of the majority was good or fairly good. A majority of the bereaved considered the bereavement care to be helpful and almost three-quarters were not considered to be in need of more follow-up. 2. Grief Response Assessment Age was found to have a modoerately positive correlation to appetite disturbance(r=.41, P<.Ol) and loss of vigor(r=.37, P<.Ol) A moderately positive correlation was found between the number of contacts and sleep disturbance(r=2.38, P<.01) Significant differences were found between men and women in regard to guilt(t=2.38, P<.05), social isolation(t=2.44, P<.05) and depersonalization(t=2.07, P<.05) with men having the more intense grief. Significant differences were found in the grief responses of somatization(F=5.82, P<.001), physical symptoms(F=5.87, P<.OOl), appetite disturbance(F=4.40, P<.Ol), despair(3.79, P<,Ol), anger(Fp2.83, P<.05), social isolation(F=3.61, P<.05), guilt(F=3.62, P<.05) and depersonalization (F = 2.58, P <.05). In the first six of these grief responses mothers scored highest, followed by husbands and then wives, In the grief response of guilt, daughters scored highest and on the grief response of depersonalization sons scored highest. Only one grief response, that of sleep disturbance(t= -2.19, P<.05) was found to be statistically significant, with those family members who died at home having the higher scores. Based on the results of this study several suggestions are presented as follows: 1. Since unresolived grief can have a detrimental effect on the bereaved person's mental and phys. ical health it would be good for the nurse, to include questions related to death of family members and the bereaved person's response to the grief, in her nursing assessment. And in the case of unresolved grief the nurse should encourage the person to talk with a trusted friend or counselor and express their fellings of grief. 2. A study to determine the degree of resolution of the grief of those in the bereavement program could be carried out by use of the Grief Experience Inventory early in their bereavement and again 13 months after the death of their family member. 3. A comparison of the grief response of the bereaved in the bereavement program and bereaved not in the program could be carried out using the Grief Experience Inventory. 4. After bereavement programs have been started in other hospice programs it would be good to carry out a joint study of bereavement outcomes of those in the bereavement programs.